We|we|PRP|O examined|examine|VBD|O whether|whether|IN|O the|the|DT|O potent|potent|JJ|O fibrogenic|fibrogenic|JJ|O cytokine|cytokine|NN|O TGF-beta1|TGF-beta1|NN|GENE could|can|MD|O induce|induce|VB|O epithelial|epithelial|JJ|O mesenchymal|mesenchymal|JJ|O transition|transition|NN|O (|(|(|O EMT|emt|NN|GENE )|)|)|O in|in|IN|O the|the|DT|O human|human|JJ|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cell|cell|NN|O line|line|NN|O ,|,|,|O A549|A549|NN|O ,|,|,|O and|and|CC|O investigated|investigate|VBD|O the|the|DT|O signaling|signaling|NN|O pathway|pathway|NN|O of|of|IN|O TGF-beta1-mediated|tgf-beta1-mediated|JJ|O EMT|emt|NN|GENE .|.|.|O 
METHODS|method|NNS|O :|:|:|O A549|A549|NN|O cells|cell|NNS|O were|be|VBD|O examined|examine|VBN|O for|for|IN|O evidence|evidence|NN|O of|of|IN|O EMT|emt|NN|GENE after|after|IN|O treatment|treatment|NN|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE .|.|.|O 
EMT|emt|NN|GENE was|be|VBD|O assessed|assess|VBN|O by|by|IN|O :|:|:|O morphology|morphology|NN|O under|under|IN|O phase-contrast|phase-contrast|JJ|O microscopy|microscopy|NN|O ;|;|:|O Western|western|JJ|O analysis|analysis|NN|O of|of|IN|O cell|cell|NN|O lysates|lysate|NNS|O for|for|IN|O expression|expression|NN|O of|of|IN|O mesenchymal|mesenchymal|JJ|O phenotypic|phenotypic|JJ|O markers|marker|NNS|O including|include|VBG|O fibronectin|fibronectin|NN|GENE EDA|eda|NNP|O (|(|(|O Fn-EDA|Fn-EDA|NN|O )|)|)|O ,|,|,|O and|and|CC|O expression|expression|NN|O of|of|IN|O epithelial|epithelial|JJ|O phenotypic|phenotypic|JJ|O markers|marker|NNS|O including|include|VBG|O E-cadherin|e-cadherin|NN|GENE (|(|(|O E-cad|E-cad|NN|O )|)|)|O .|.|.|O 
Markers|marker|NNS|O of|of|IN|O fibrogenesis|fibrogenesis|NN|O ,|,|,|O including|include|VBG|O collagens|collagen|NNS|O and|and|CC|O connective|connective|NN|GENE tissue|tissue|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE (|(|(|O CTGF|Ctgf|NN|GENE )|)|)|O were|be|VBD|O also|also|RB|O evaluated|evaluate|VBN|O by|by|IN|O measuring|measure|VBG|O mRNA|mRNA|NN|O level|level|NN|O using|use|VBG|O RT-PCR|rt-pcr|NN|O ,|,|,|O and|and|CC|O protein|protein|NN|O by|by|IN|O immunofluorescence|immunofluorescence|NN|O or|or|CC|O Western|western|NN|O blotting|blotting|NN|O .|.|.|O 
Signaling|signaling|NN|O pathways|pathway|NNS|O for|for|IN|O EMT|emt|NN|GENE were|be|VBD|O characterized|characterize|VBN|O by|by|IN|O Western|western|JJ|O analysis|analysis|NN|O of|of|IN|O cell|cell|NN|O lysates|lysate|NNS|O using|use|VBG|O monoclonal|monoclonal|JJ|O antibodies|antibody|NNS|O to|to|TO|O detect|detect|VB|O phosphorylated|phosphorylated|JJ|O Erk1/2|Erk1/2|NN|O and|and|CC|O Smad2|Smad2|NN|GENE after|after|IN|O TGF-beta1|TGF-beta1|NN|GENE treatment|treatment|NN|O in|in|IN|O the|the|DT|O presence|presence|NN|O or|or|CC|O absence|absence|NN|O of|of|IN|O MEK|MEK|NN|O inhibitors|inhibitor|NNS|O .|.|.|O 
The|the|DT|O role|role|NN|O of|of|IN|O Smad2|Smad2|NN|GENE in|in|IN|O TGF-beta1-mediated|tgf-beta1-mediated|JJ|O EMT|emt|NN|GENE was|be|VBD|O investigated|investigate|VBN|O using|use|VBG|O siRNA|siRNA|NNP|O .|.|.|O 
RESULTS|result|NNS|O :|:|:|O The|the|DT|O data|datum|NNS|O showed|show|VBD|O that|that|IN|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O but|but|CC|O not|not|RB|O TNF-alpha|TNF-alpha|NN|GENE or|or|CC|O IL-1beta|IL-1beta|NN|GENE ,|,|,|O induced|induce|VBD|O A549|A549|NN|O cells|cell|NNS|O with|with|IN|O an|a|DT|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O type|type|NN|O II|II|CD|O cell|cell|NN|O phenotype|phenotype|NN|O to|to|TO|O undergo|undergo|VB|O EMT|emt|NN|GENE in|in|IN|O a|a|DT|O time-and|time-and|JJ|O concentration-dependent|concentration-dependent|JJ|O manner|manner|NN|O .|.|.|O 
The|the|DT|O process|process|NN|O of|of|IN|O EMT|emt|NN|GENE was|be|VBD|O accompanied|accompany|VBN|O by|by|IN|O morphological|morphological|JJ|O alteration|alteration|NN|O and|and|CC|O expression|expression|NN|O of|of|IN|O the|the|DT|O fibroblast|fibroblast|NN|O phenotypic|phenotypic|JJ|O markers|marker|NNS|O Fn-EDA|Fn-EDA|NN|O and|and|CC|O vimentin|vimentin|NN|GENE ,|,|,|O concomitant|concomitant|JJ|O with|with|IN|O a|a|DT|O downregulation|downregulation|NN|O of|of|IN|O the|the|DT|O epithelial|epithelial|JJ|O phenotype|phenotype|NN|O marker|marker|NN|O E-cad|E-cad|NN|O .|.|.|O 
Furthermore|furthermore|RB|O ,|,|,|O cells|cell|NNS|O that|that|WDT|O had|have|VBD|O undergone|undergo|VBN|O EMT|emt|NN|GENE showed|show|VBD|O enhanced|enhance|VBN|O expression|expression|NN|O of|of|IN|O markers|marker|NNS|O of|of|IN|O fibrogenesis|fibrogenesis|NN|O including|include|VBG|O collagens|collagen|NNS|O type|type|NN|O I|i|CD|O and|and|CC|O III|III|CD|O and|and|CC|O CTGF|Ctgf|NN|GENE .|.|.|O 
TGF-beta1-induced|tgf-beta1-induced|JJ|O EMT|emt|NN|GENE occurred|occur|VBD|O through|through|IN|O phosphorylation|phosphorylation|NN|O of|of|IN|O Smad2|Smad2|NN|GENE and|and|CC|O was|be|VBD|O inhibited|inhibit|VBN|O by|by|IN|O Smad2|Smad2|NN|GENE gene|gene|NN|O silencing|silencing|NN|O ;|;|:|O MEK|MEK|NN|O inhibitors|inhibitor|NNS|O failed|fail|VBD|O to|to|TO|O attenuate|attenuate|VB|O either|either|CC|O EMT-associated|emt-associated|JJ|O Smad2|Smad2|NN|GENE phosphorylation|phosphorylation|NN|O or|or|CC|O the|the|DT|O observed|observe|VBN|O phenotypic|phenotypic|JJ|O changes|change|NNS|O .|.|.|O 
CONCLUSION|conclusion|NN|O :|:|:|O Our|our|PRP$|O study|study|NN|O shows|show|VBZ|O that|that|IN|O TGF-beta1|TGF-beta1|NN|GENE induces|induce|VBZ|O A549|A549|NN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O to|to|TO|O undergo|undergo|VB|O EMT|emt|NN|GENE via|via|IN|O Smad2|Smad2|NN|GENE activation|activation|NN|O .|.|.|O 
Our|our|PRP$|O data|datum|NNS|O support|support|VBP|O the|the|DT|O concept|concept|NN|O of|of|IN|O EMT|emt|NN|GENE in|in|IN|O lung|lung|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O ,|,|,|O and|and|CC|O suggest|suggest|VBP|O the|the|DT|O need|need|NN|O for|for|IN|O further|further|JJ|O studies|study|NNS|O to|to|TO|O investigate|investigate|VB|O the|the|DT|O phenomenon|phenomenon|NN|O .|.|.|O 
Negative|negative|JJ|O regulation|regulation|NN|O of|of|IN|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O by|by|IN|O PTEN|PTEN|NN|GENE (|(|(|O Phosphatase|phosphatase|NN|O and|and|CC|O Tensin|tensin|NNP|O Homolog|homolog|NNP|O Deleted|deleted|JJ|O on|on|IN|O chromosome|chromosome|NN|O 10|10|CD|O )|)|)|O .|.|.|O 
RATIONALE|rationale|NN|O :|:|:|O Myofibroblasts|myofibroblast|NNS|O are|be|VBP|O primary|primary|JJ|O effector|effector|NN|O cells|cell|NNS|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O .|.|.|O 
Defining|define|VBG|O mechanisms|mechanism|NNS|O of|of|IN|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O may|may|MD|O be|be|VB|O critical|critical|JJ|O to|to|TO|O the|the|DT|O development|development|NN|O of|of|IN|O novel|novel|JJ|O therapeutic|therapeutic|JJ|O agents|agent|NNS|O .|.|.|O 
OBJECTIVE|objective|NN|O :|:|:|O To|to|TO|O show|show|VB|O that|that|IN|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O is|be|VBZ|O regulated|regulate|VBN|O by|by|IN|O phosphatase|phosphatase|NN|O and|and|CC|O tensin|tensin|NN|O homolog|homolog|NN|O deleted|delete|VBN|O on|on|IN|O chromosome|chromosome|NN|O 10|10|CD|O (|(|(|O PTEN|PTEN|NN|GENE )|)|)|O activity|activity|NN|O in|in|FW|O vivo|vivo|FW|O ,|,|,|O and|and|CC|O to|to|TO|O identify|identify|VB|O a|a|DT|O potential|potential|JJ|O mechanism|mechanism|NN|O by|by|IN|O which|which|WDT|O this|this|DT|O occurs|occur|VBZ|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O We|we|PRP|O used|use|VBD|O tissue|tissue|NN|O sections|section|NNS|O of|of|IN|O surgical|surgical|JJ|O lung|lung|NN|O biopsies|biopsy|NNS|O from|from|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O to|to|TO|O localize|localize|VB|O expression|expression|NN|O of|of|IN|O PTEN|PTEN|NN|GENE and|and|CC|O alpha-smooth-muscle-actin|alpha-smooth-muscle-actin|NN|GENE (|(|(|O alpha-SMA|alpha-SMA|NN|GENE )|)|)|O .|.|.|O 
We|we|PRP|O used|use|VBD|O cell|cell|NN|O culture|culture|NN|O of|of|IN|O pten|PTEN|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O and|and|CC|O wild-type|wild-type|JJ|O fibroblasts|fibroblast|NNS|O ,|,|,|O as|as|RB|O well|well|RB|O as|as|IN|O adenoviral|adenoviral|JJ|O strategies|strategy|NNS|O and|and|CC|O pharmacologic|pharmacologic|JJ|O inhibitors|inhibitor|NNS|O ,|,|,|O to|to|TO|O determine|determine|VB|O the|the|DT|O mechanism|mechanism|NN|O by|by|IN|O which|which|WDT|O PTEN|PTEN|NN|GENE inhibits|inhibit|VBZ|O alpha-SMA|alpha-SMA|NN|GENE ,|,|,|O fibroblast|fibroblast|NN|O proliferation|proliferation|NN|O ,|,|,|O and|and|CC|O collagen|collagen|NN|O production|production|NN|O .|.|.|O 
RESULTS|result|NNS|O :|:|:|O In|in|IN|O human|human|JJ|O lung|lung|NN|O specimens|specimen|NNS|O of|of|IN|O IPF|IPF|NN|O ,|,|,|O myofibroblasts|myofibroblast|NNS|O within|within|IN|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O demonstrated|demonstrate|VBD|O diminished|diminish|VBN|O PTEN|PTEN|NN|GENE expression|expression|NN|O .|.|.|O 
Furthermore|furthermore|RB|O ,|,|,|O inhibition|inhibition|NN|O of|of|IN|O PTEN|PTEN|NN|GENE in|in|IN|O mice|mouse|NNS|O worsened|worsen|VBD|O bleomycin-induced|bleomycin-induced|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
In|in|IN|O pten|PTEN|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O fibroblasts|fibroblast|NNS|O ,|,|,|O and|and|CC|O in|in|IN|O normal|normal|JJ|O fibroblasts|fibroblast|NNS|O in|in|IN|O which|which|WDT|O PTEN|PTEN|NNP|GENE was|be|VBD|O inhibited|inhibit|VBN|O ,|,|,|O alpha-SMA|alpha-SMA|NN|GENE ,|,|,|O proliferation|proliferation|NN|O ,|,|,|O and|and|CC|O collagen|collagen|NN|O production|production|NN|O was|be|VBD|O upregulated|upregulate|VBN|O .|.|.|O 
Addition|addition|NN|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE to|to|TO|O wild-type|wild-type|JJ|O cells|cell|NNS|O ,|,|,|O but|but|CC|O not|not|RB|O pten|PTEN|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O cells|cell|NNS|O ,|,|,|O resulted|result|VBD|O in|in|IN|O increased|increase|VBN|O alpha-SMA|alpha-SMA|NN|GENE expression|expression|NN|O in|in|IN|O a|a|DT|O time-dependent|time-dependent|JJ|O fashion|fashion|NN|O .|.|.|O 
In|in|IN|O pten|PTEN|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O cells|cell|NNS|O ,|,|,|O reconstitution|reconstitution|NN|O of|of|IN|O PTEN|PTEN|NNP|GENE decreased|decrease|VBD|O alpha-SMA|alpha-SMA|NN|GENE expression|expression|NN|O ,|,|,|O proliferation|proliferation|NN|O ,|,|,|O and|and|CC|O collagen|collagen|NN|O production|production|NN|O ,|,|,|O whereas|whereas|IN|O overexpression|overexpression|NN|O of|of|IN|O PTEN|PTEN|NN|GENE in|in|IN|O wild-type|wild-type|JJ|O cells|cell|NNS|O inhibited|inhibit|VBD|O transforming-growth-factor-beta-induced|transforming-growth-factor-beta-induced|JJ|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O .|.|.|O 
It|it|PRP|O was|be|VBD|O observed|observe|VBN|O that|that|IN|O both|both|CC|O the|the|DT|O protein|protein|NN|O and|and|CC|O lipid|lipid|NN|O phosphatase|phosphatase|NN|O actions|action|NNS|O of|of|IN|O PTEN|PTEN|NN|GENE were|be|VBD|O capable|capable|JJ|O of|of|IN|O modulating|modulate|VBG|O the|the|DT|O myofibroblast|myofibroblast|NN|O phenotype|phenotype|NN|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O The|the|DT|O results|result|NNS|O indicate|indicate|VBP|O that|that|IN|O in|in|IN|O IPF|IPF|NNP|O ,|,|,|O myofibroblasts|myofibroblast|NNS|O have|have|VBP|O diminished|diminish|VBN|O PTEN|PTEN|NN|GENE expression|expression|NN|O .|.|.|O 
Inhibition|inhibition|NN|O of|of|IN|O PTEN|PTEN|NN|GENE in|in|FW|O vivo|vivo|FW|O promotes|promote|VBZ|O fibrosis|fibrosis|NN|O ,|,|,|O and|and|CC|O PTEN|PTEN|NN|GENE inhibits|inhibit|VBZ|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O in|in|FW|O vitro|vitro|FW|O .|.|.|O 
Different|different|JJ|O effects|effect|NNS|O of|of|IN|O growth|growth|NN|O factors|factor|NNS|O on|on|IN|O proliferation|proliferation|NN|O and|and|CC|O matrix|matrix|NN|O production|production|NN|O of|of|IN|O normal|normal|JJ|O and|and|CC|O fibrotic|fibrotic|JJ|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O .|.|.|O 
OBJECTIVES|objective|NNS|O AND|and|CC|O METHODS|method|NNS|O :|:|:|O In|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O proliferation|proliferation|NN|O of|of|IN|O fibroblasts|fibroblast|NNS|O and|and|CC|O increased|increase|VBD|O matrix|matrix|NN|O deposition|deposition|NN|O result|result|VBP|O in|in|IN|O pulmonary|pulmonary|JJ|O damage|damage|NN|O and|and|CC|O respiratory|respiratory|JJ|O insufficiency|insufficiency|NN|O .|.|.|O 
We|we|PRP|O cultured|culture|VBD|O human|human|JJ|O fibroblasts|fibroblast|NNS|O from|from|IN|O lung|lung|NN|O biopsies|biopsy|NNS|O of|of|IN|O healthy|healthy|JJ|O adults|adult|NNS|O and|and|CC|O of|of|IN|O three|three|CD|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O (|(|(|O histologically|histological|RB|O usual|usual|JJ|O interstital|interstital|JJ|O pneumonitis|pneumonitis|NN|O ,|,|,|O UIP|UIP|NNP|O )|)|)|O in|in|IN|O order|order|NN|O to|to|TO|O compare|compare|VB|O proliferation|proliferation|NN|O (|(|(|O [|[|(|O (|(|(|O 3|3|LS|O )|)|)|O H|h|NN|O ]|]|)|O thymidine|thymidine|NN|O incorporation|incorporation|NN|O ,|,|,|O cell|cell|NN|O count|count|NN|O )|)|)|O and|and|CC|O matrix|matrix|NN|O protein|protein|NN|O expression|expression|NN|O (|(|(|O immune|immune|JJ|O fluorescence|fluorescence|NN|O ,|,|,|O quantification|quantification|NN|O of|of|IN|O fibronectin|fibronectin|NN|GENE synthesis|synthesis|NN|O using|use|VBG|O time-resolved|time-resolved|JJ|O immune|immune|JJ|O fluorescence|fluorescence|NN|O )|)|)|O of|of|IN|O normal|normal|JJ|O and|and|CC|O UIP|uip|JJ|O fibroblasts|fibroblast|NNS|O in|in|IN|O response|response|NN|O to|to|TO|O various|various|JJ|O growth|growth|NN|O factors|factor|NNS|O .|.|.|O 
FINDINGS|finding|NNS|O :|:|:|O The|the|DT|O growth|growth|NN|O factors|factor|NNS|O platelet-derived|platelet-derived|JJ|O growth|growth|NN|O factor-BB|factor-BB|NN|O (|(|(|O PDGF|PDGF|NN|O )|)|)|O ,|,|,|O epidermal|epidermal|JJ|O growth|growth|NN|O factor|factor|NN|O (|(|(|O EGF|EGF|NN|O )|)|)|O ,|,|,|O insulin|insulin|NN|O growth|growth|NN|O factor-1|factor-1|NN|O (|(|(|O IGF-1|IGF-1|NN|GENE )|)|)|O ,|,|,|O insulin-like|insulin-like|JJ|O growth|growth|NN|O factor-2|factor-2|NN|O (|(|(|O IGF-2|IGF-2|NN|GENE )|)|)|O ,|,|,|O tumor|tumor|NN|GENE necrosis|necrosis|NN|GENE factor|factor|NN|GENE alpha|alpha|NN|GENE (|(|(|O TNFalpha|TNFalpha|NN|GENE )|)|)|O ,|,|,|O Transforming|Transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE (|(|(|O TGFbeta|TGFbeta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O )|)|)|O ,|,|,|O and|and|CC|O fibroblast|fibroblast|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE 2|2|NN|GENE (|(|(|O FGF-2|FGF-2|NN|GENE )|)|)|O stimulate|stimulate|VBP|O proliferation|proliferation|NN|O of|of|IN|O normal|normal|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O significantly|significant|RB|O more|much|RBR|O than|than|IN|O proliferation|proliferation|NN|O of|of|IN|O UIP|UIP|NNP|O fibroblasts|fibroblast|NNS|O .|.|.|O 
Immunofluorescence|immunofluorescence|NN|O reveals|reveal|VBZ|O extensive|extensive|JJ|O expression|expression|NN|O of|of|IN|O collagen|collagen|NN|O I|i|CD|O ,|,|,|O collagen|collagen|NN|O III|III|CD|O ,|,|,|O and|and|CC|O fibronectin|fibronectin|NN|GENE induced|induce|VBN|O by|by|IN|O serum|serum|NN|O ,|,|,|O TGFbeta|TGFbeta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O ,|,|,|O and|and|CC|O TNFalpha|TNFalpha|NN|GENE .|.|.|O 
This|this|DT|O expression|expression|NN|O is|be|VBZ|O more|much|RBR|O pronounced|pronounced|JJ|O in|in|IN|O UIP|UIP|NNP|O fibroblasts|fibroblast|NNS|O than|than|IN|O in|in|IN|O normal|normal|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
Quantification|quantification|NN|O of|of|IN|O fibronectin|fibronectin|NN|GENE synthesis|synthesis|NN|O reveals|reveal|VBZ|O an|a|DT|O enhanced|enhance|VBN|O fibronectin|fibronectin|NN|GENE synthesis|synthesis|NN|O by|by|IN|O UIP|UIP|NNP|O fibroblasts|fibroblast|NNS|O in|in|IN|O response|response|NN|O to|to|TO|O PDGF|PDGF|NN|O ,|,|,|O EGF|EGF|NN|O ,|,|,|O IGF-1|IGF-1|NN|GENE ,|,|,|O IGF-2|IGF-2|NN|GENE ,|,|,|O TNFalpha|TNFalpha|NN|GENE ,|,|,|O TGFbeta|TGFbeta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O ,|,|,|O and|and|CC|O FGF-2|FGF-2|NN|GENE )|)|)|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O Fibroblasts|fibroblast|NNS|O from|from|IN|O normal|normal|JJ|O and|and|CC|O UIP|UIP|NNP|O lungs|lung|NNS|O differ|differ|VBP|O in|in|IN|O their|their|PRP$|O response|response|NN|O to|to|TO|O growth|growth|NN|O factors|factor|NNS|O :|:|:|O Whereas|whereas|IN|O normal|normal|JJ|O fibroblasts|fibroblast|NNS|O show|show|VBP|O a|a|DT|O predominantly|predominant|RB|O proliferative|proliferative|JJ|O response|response|NN|O ,|,|,|O UIP|UIP|NNP|O fibroblasts|fibroblast|NNS|O show|show|VBP|O an|a|DT|O enhanced|enhance|VBN|O synthetic|synthetic|JJ|O activity|activity|NN|O .|.|.|O 
Different|different|JJ|O fibroblast|fibroblast|NN|O responses|response|NNS|O may|may|MD|O contribute|contribute|VB|O to|to|TO|O progressive|progressive|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O patients|patient|NNS|O with|with|IN|O UIP|UIP|NNP|O .|.|.|O 
Proliferation|proliferation|NN|O of|of|IN|O pulmonary|pulmonary|JJ|O interstitial|interstitial|JJ|O fibroblasts|fibroblast|NNS|O is|be|VBZ|O mediated|mediate|VBN|O by|by|IN|O transforming-growth-factor-beta1-induced|transforming-growth-factor-beta1-induced|JJ|O release|release|NN|O of|of|IN|O extracellular|extracellular|JJ|O fibroblast|fibroblast|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE 2|2|NN|GENE and|and|CC|O phosphorylation|phosphorylation|NN|O of|of|IN|O p38|p38|NN|GENE MAPK|mapk|NN|O and|and|CC|O JNK|jnk|NN|GENE .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O ;|;|:|O a|a|DT|O progressive|progressive|JJ|O lung|lung|NN|O disease|disease|NN|O )|)|)|O is|be|VBZ|O characterized|characterize|VBN|O by|by|IN|O parenchymal|parenchymal|JJ|O remodeling|remodeling|NN|O with|with|IN|O enlarged|enlarged|JJ|O air|air|NN|O spaces|space|NNS|O called|call|VBN|O honeycomb|honeycomb|NN|O cysts|cyst|NNS|O and|and|CC|O palisades|palisade|NNS|O of|of|IN|O fibroblasts|fibroblast|NNS|O called|call|VBN|O fibroblast|fibroblast|NN|O foci|focus|NNS|O .|.|.|O 
In|in|IN|O IPF|IPF|NN|O ,|,|,|O lung|lung|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O covering|cover|VBG|O honeycomb|honeycomb|NN|O cysts|cyst|NNS|O and|and|CC|O fibroblast|fibroblast|NN|O foci|focus|NNS|O aberrantly|aberrant|RB|O express|express|VBP|O the|the|DT|O active|active|JJ|O conformation|conformation|NN|O of|of|IN|O the|the|DT|O potent|potent|JJ|O fibrogenic|fibrogenic|JJ|O cytokine|cytokine|NN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O .|.|.|O 
Using|use|VBG|O explanted|explanted|JJ|O rat|rat|NN|O lung|lung|NN|O slices|slice|NNS|O ,|,|,|O we|we|PRP|O transfected|transfect|VBD|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O with|with|IN|O the|the|DT|O retrovirus|retrovirus|NN|O pMX|pMX|NN|O containing|contain|VBG|O a|a|DT|O site-directed|site-directed|JJ|O mutation|mutation|NN|O in|in|IN|O which|which|WDT|O Cys223|Cys223|NN|O and|and|CC|O Cys225|Cys225|NN|O were|be|VBD|O substituted|substitute|VBN|O with|with|IN|O serines|serine|NNS|O ,|,|,|O resulting|result|VBG|O in|in|IN|O release|release|NN|O of|of|IN|O biologically|biological|RB|O active|active|JJ|O TGF-beta1|TGF-beta1|NN|GENE and|and|CC|O fibroblast|fibroblast|NN|O proliferation|proliferation|NN|O and|and|CC|O remodeling|remodel|VBG|O that|that|IN|O resembled|resemble|VBD|O IPF|IPF|NN|O .|.|.|O 
Fibroblasts|fibroblast|NNS|O obtained|obtain|VBN|O from|from|IN|O transfected|transfect|VBN|O explants|explant|NNS|O and|and|CC|O in|in|IN|O culture|culture|NN|O for|for|IN|O 6|6|CD|O weeks|week|NNS|O incorporated|incorporate|VBN|O 6.59|6.59|CD|O +|+|CC|O /|/|:|O -|-|:|O 1.55-fold|1.55-fold|RB|O more|much|RBR|O [|[|(|O 3H|3H|NN|O ]|]|)|O thymidine|thymidine|NN|O compared|compare|VBN|O with|with|IN|O control|control|JJ|O fibroblasts|fibroblast|NNS|O without|without|IN|O transfection|transfection|NN|O or|or|CC|O fibroblasts|fibroblast|NNS|O obtained|obtain|VBN|O from|from|IN|O transfected|transfect|VBN|O explants|explant|NNS|O cultured|culture|VBN|O with|with|IN|O antibody|antibody|NN|O to|to|TO|O fibroblast|fibroblast|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE 2|2|NN|GENE (|(|(|O FGF-2|FGF-2|NN|GENE )|)|)|O .|.|.|O 
Primary|primary|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O obtained|obtain|VBN|O from|from|IN|O normal|normal|JJ|O rat|rat|NN|O lungs|lung|NNS|O cultured|culture|VBN|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE expressed|express|VBD|O increased|increase|VBN|O levels|level|NNS|O of|of|IN|O phosphorylated|phosphorylate|VBN|O p38|p38|NN|GENE MAPK|mapk|NN|O and|and|CC|O JNK|jnk|NN|GENE ,|,|,|O but|but|CC|O not|not|RB|O ERK1/2|ERK1/2|NN|GENE .|.|.|O 
The|the|DT|O presence|presence|NN|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE caused|cause|VBD|O an|a|DT|O immediate|immediate|JJ|O release|release|NN|O of|of|IN|O extracellular|extracellular|JJ|O FGF-2|FGF-2|NN|GENE from|from|IN|O primary|primary|JJ|O pulmonary|pulmonary|JJ|O fibroblasts|fibroblast|NNS|O ;|;|:|O and|and|CC|O in|in|IN|O the|the|DT|O presence|presence|NN|O of|of|IN|O anti-FGF-2|anti-fgf-2|JJ|O antibody|antibody|NN|O ,|,|,|O phosphorylated|phosphorylate|VBN|O p38|p38|NN|GENE MAPK|mapk|NN|O and|and|CC|O JNK|jnk|NN|GENE were|be|VBD|O abrogated|abrogate|VBN|O .|.|.|O 
TGF-beta|TGF-beta|NN|GENE inhibits|inhibit|VBZ|O cell|cell|NN|O proliferation|proliferation|NN|O by|by|IN|O suppression|suppression|NN|O of|of|IN|O c-Myc|c-myc|NN|O and|and|CC|O induction|induction|NN|O of|of|IN|O p15INK46|p15INK46|NN|O ,|,|,|O p21CIP1|p21CIP1|NN|O ,|,|,|O or|or|CC|O p27KIP|p27KIP|NN|O .|.|.|O 
Fibroblasts|fibroblast|NNS|O cultured|culture|VBN|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE showed|show|VBD|O no|no|DT|O regulation|regulation|NN|O of|of|IN|O c-Myc|c-myc|NN|O or|or|CC|O induction|induction|NN|O of|of|IN|O p15INK46|p15INK46|NN|O ,|,|,|O p21CIP1|p21CIP1|NN|O ,|,|,|O or|or|CC|O p27KIP|p27KIP|NN|O .|.|.|O 
These|these|DT|O findings|finding|NNS|O suggest|suggest|VBP|O that|that|IN|O pulmonary|pulmonary|JJ|O fibroblasts|fibroblast|NNS|O may|may|MD|O not|not|RB|O respond|respond|VB|O to|to|TO|O the|the|DT|O anti-proliferative|anti-proliferative|JJ|O effects|effect|NNS|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O but|but|CC|O proliferate|proliferate|VBP|O in|in|IN|O response|response|NN|O to|to|TO|O TGF-beta1|TGF-beta1|NN|GENE indirectly|indirect|RB|O by|by|IN|O the|the|DT|O release|release|NN|O of|of|IN|O FGF-2|FGF-2|NN|GENE ,|,|,|O which|which|WDT|O induces|induce|VBZ|O phosphorylation|phosphorylation|NN|O of|of|IN|O p38|p38|NN|GENE MAPK|mapk|NN|O and|and|CC|O JNK|jnk|NN|GENE .|.|.|O 
Th1/Th2|Th1/Th2|NN|O cytokine|cytokine|NN|O gene|gene|NN|O polymorphisms|polymorphism|NNS|O in|in|IN|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
We|we|PRP|O investigated|investigate|VBD|O 30|30|CD|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O and|and|CC|O 103|103|CD|O healthy|healthy|JJ|O volunteers|volunteer|NNS|O for|for|IN|O the|the|DT|O cytokines|cytokine|NNS|O polymorphisms|polymorphism|NNS|O of|of|IN|O the|the|DT|O IL-1alpha|IL-1alpha|NN|O ,|,|,|O IL-1beta|IL-1beta|NN|GENE ,|,|,|O IL-1R|IL-1R|NN|O ,|,|,|O IL-1RA|IL-1RA|NN|O ,|,|,|O IL-2|IL-2|NN|O ,|,|,|O IL-4|IL-4|NN|GENE ,|,|,|O IL-6|IL-6|NN|GENE ,|,|,|O IL-10|IL-10|NN|GENE ,|,|,|O IL-12|IL-12|NN|O ,|,|,|O tumor|tumor|NN|GENE necrosis|necrosis|NN|GENE factor|factor|NN|GENE alpha|alpha|NN|GENE ,|,|,|O interferon-gamma|interferon-gamma|NN|O ,|,|,|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE ,|,|,|O IL-1beta|IL-1beta|NN|GENE ,|,|,|O IL-2|IL-2|NN|O ,|,|,|O IL-4|IL-4|NN|GENE ,|,|,|O and|and|CC|O IL-4RA|IL-4RA|NN|O genes|gene|NNS|O .|.|.|O 
The|the|DT|O strongest|strong|JJS|O correlation|correlation|NN|O of|of|IN|O a|a|DT|O genotype|genotype|NN|O with|with|IN|O the|the|DT|O disease|disease|NN|O was|be|VBD|O found|find|VBN|O for|for|IN|O gene|gene|NN|O polymorphisms|polymorphism|NNS|O at|at|IN|O the|the|DT|O promotor|promotor|NN|O region|region|NN|O of|of|IN|O IL-4|IL-4|NN|GENE ,|,|,|O where|where|WRB|O the|the|DT|O CT|ct|NN|O genotypes|genotype|NNS|O at|at|IN|O the|the|DT|O positions|position|NNS|O (|(|(|O -590|-590|CD|O )|)|)|O and|and|CC|O (|(|(|O -33|-33|CD|O )|)|)|O were|be|VBD|O more|many|JJR|O frequent|frequent|JJ|O in|in|IN|O the|the|DT|O IPF|IPF|NN|O group|group|NN|O (|(|(|O P|p|NN|O <|<|JJR|O 0.0001|0.0001|CD|O ,|,|,|O P|p|NN|O (|(|(|O corr|Corr|NN|O )|)|)|O <|<|JJR|O 0.0022|0.0022|CD|O ;|;|:|O vs|vs|CC|O P|p|NN|O <|<|VBG|O 0.0001|0.0001|CD|O ,|,|,|O P|p|NN|O (|(|(|O corr|Corr|NN|O )|)|)|O <|<|JJR|O 0.0022|0.0022|CD|O )|)|)|O .|.|.|O 
Our|our|PRP$|O results|result|NNS|O support|support|VBP|O the|the|DT|O idea|idea|NN|O of|of|IN|O the|the|DT|O pathogenic|pathogenic|JJ|O role|role|NN|O of|of|IN|O cytokine|cytokine|NN|O gene|gene|NN|O polymorphisms|polymorphism|NNS|O in|in|IN|O the|the|DT|O etiology|etiology|NN|O and|and|CC|O pathogenesis|pathogenesis|NN|O of|of|IN|O IPF|IPF|NN|O ,|,|,|O with|with|IN|O emphasize|emphasize|VBP|O on|on|IN|O the|the|DT|O IL-4|IL-4|NN|GENE promotor|promotor|NN|O gene|gene|NN|O polymorphisms|polymorphism|NNS|O .|.|.|O 
Defect|defect|NN|O of|of|IN|O pro-hepatocyte-growth-factor|pro-hepatocyte-growth-factor|JJ|O activation|activation|NN|O by|by|IN|O fibroblasts|fibroblast|NNS|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
RATIONALE|rationale|NN|O AND|and|CC|O OBJECTIVES|objective|NNS|O :|:|:|O Hepatocyte|Hepatocyte|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE (|(|(|O HGF|HGF|NN|GENE )|)|)|O protects|protect|VBZ|O against|against|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O in|in|IN|O several|several|JJ|O animal|animal|NN|O models|model|NNS|O .|.|.|O 
Pro-HGF|pro-hgf|JJ|O activation|activation|NN|O to|to|TO|O HGF|HGF|NN|GENE is|be|VBZ|O subjected|subject|VBN|O to|to|TO|O regulation|regulation|NN|O by|by|IN|O its|its|PRP$|O activator|activator|NN|O (|(|(|O HGFA|HGFA|NN|O )|)|)|O ,|,|,|O a|a|DT|O serine|serine|NN|GENE protease|protease|NN|GENE ,|,|,|O and|and|CC|O HGFA-specific|hgfa-specific|JJ|O inhibitors|inhibitor|NNS|O (|(|(|O HAI-1|HAI-1|NN|GENE and|and|CC|O HAI-2|HAI-2|NN|GENE )|)|)|O .|.|.|O 
Our|our|PRP$|O hypothesis|hypothesis|NN|O was|be|VBD|O that|that|IN|O fibroblasts|fibroblast|NNS|O from|from|IN|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O had|have|VBD|O an|a|DT|O altered|altered|JJ|O capacity|capacity|NN|O to|to|TO|O activate|activate|VB|O pro-HGF|pro-HGF|NN|O in|in|FW|O vitro|vitro|FW|O compared|compare|VBN|O with|with|IN|O control|control|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O We|we|PRP|O measured|measure|VBD|O the|the|DT|O kinetics|kinetic|NNS|O of|of|IN|O pro-HGF|pro-HGF|NN|O activation|activation|NN|O in|in|IN|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O from|from|IN|O control|control|JJ|O subjects|subject|NNS|O and|and|CC|O from|from|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O by|by|IN|O Western|western|NN|O blot|blot|NN|O .|.|.|O 
HGFA|HGFA|NNP|O ,|,|,|O HAI-1|HAI-1|NN|GENE ,|,|,|O and|and|CC|O HAI-2|HAI-2|NN|GENE expression|expression|NN|O was|be|VBD|O evaluated|evaluate|VBN|O by|by|IN|O immunohistochemistry|immunohistochemistry|NN|O ,|,|,|O RNA|rna|NN|O protection|protection|NN|O assay|assay|NN|O ,|,|,|O and|and|CC|O Western|western|NN|O blot|blot|NN|O .|.|.|O 
We|we|PRP|O evaluated|evaluate|VBD|O the|the|DT|O effect|effect|NN|O of|of|IN|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O and|and|CC|O PGE|PGE|NN|O (|(|(|O 2|2|CD|O )|)|)|O on|on|IN|O pro-HGF|pro-HGF|NN|O activation|activation|NN|O and|and|CC|O HGFA|HGFA|NN|O ,|,|,|O HAI-1|HAI-1|NN|GENE ,|,|,|O and|and|CC|O HAI-2|HAI-2|NN|GENE expression|expression|NN|O .|.|.|O 
MAIN|main|NNP|O RESULTS|result|NNS|O :|:|:|O Lung|lung|NN|O fibroblasts|fibroblast|NNS|O activated|activate|VBD|O pro-HGF|pro-HGF|NN|O in|in|FW|O vitro|vitro|FW|O .|.|.|O 
Pro-HGF|pro-hgf|JJ|O activation|activation|NN|O was|be|VBD|O inhibited|inhibit|VBN|O by|by|IN|O serine|serine|NN|GENE protease|protease|NN|GENE inhibitors|inhibitor|NNS|O ,|,|,|O by|by|IN|O an|a|DT|O anti-HGFA|anti-hgfa|JJ|O antibody|antibody|NN|O ,|,|,|O as|as|RB|O well|well|RB|O as|as|IN|O by|by|IN|O HAI-1|HAI-1|NN|GENE and|and|CC|O HAI-2|HAI-2|NN|GENE .|.|.|O 
Pro-HGF|pro-hgf|JJ|O activation|activation|NN|O by|by|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O was|be|VBD|O reduced|reduce|VBN|O compared|compare|VBN|O with|with|IN|O control|control|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
In|in|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O HGFA|HGFA|NN|O expression|expression|NN|O was|be|VBD|O lower|low|JJR|O and|and|CC|O HAI-1|HAI-1|NN|GENE and|and|CC|O HAI-2|HAI-2|NN|GENE expression|expression|NN|O was|be|VBD|O higher|high|JJR|O compared|compare|VBN|O with|with|IN|O control|control|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
PGE|PGE|NNP|O (|(|(|O 2|2|LS|O )|)|)|O stimulated|stimulate|VBN|O pro-HGF|pro-HGF|NN|O activation|activation|NN|O through|through|IN|O increased|increase|VBN|O expression|expression|NN|O of|of|IN|O HGFA|HGFA|NN|O and|and|CC|O decreased|decrease|VBD|O expression|expression|NN|O of|of|IN|O its|its|PRP$|O inhibitor|inhibitor|NN|O HAI-2|HAI-2|NN|GENE .|.|.|O 
In|in|IN|O contrast|contrast|NN|O ,|,|,|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O reduced|reduce|VBD|O the|the|DT|O ability|ability|NN|O of|of|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O to|to|TO|O activate|activate|VB|O pro-HGF|pro-HGF|NN|O through|through|IN|O decreased|decrease|VBN|O expression|expression|NN|O of|of|IN|O HGFA|HGFA|NN|O and|and|CC|O increased|increase|VBN|O expression|expression|NN|O of|of|IN|O its|its|PRP$|O inhibitors|inhibitor|NNS|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O have|have|VBP|O a|a|DT|O low|low|JJ|O capacity|capacity|NN|O to|to|TO|O activate|activate|VB|O pro-HGF|pro-HGF|NN|O in|in|FW|O vitro|vitro|FW|O via|via|IN|O a|a|DT|O low|low|JJ|O level|level|NN|O of|of|IN|O HGFA|HGFA|NN|O expression|expression|NN|O and|and|CC|O high|high|JJ|O levels|level|NNS|O of|of|IN|O HAI-1|HAI-1|NN|GENE and|and|CC|O HAI-2|HAI-2|NN|GENE expression|expression|NN|O ,|,|,|O and|and|CC|O PGE|PGE|NNP|O (|(|(|O 2|2|LS|O )|)|)|O is|be|VBZ|O able|able|JJ|O to|to|TO|O partially|partial|RB|O correct|correct|VB|O this|this|DT|O defect|defect|NN|O .|.|.|O 
The|the|DT|O idiopathic|idiopathic|JJ|O interstitial|interstitial|JJ|O pneumonias|pneumonia|NNS|O ,|,|,|O especially|especial|RB|O the|the|DT|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O are|be|VBP|O life-threatening|life-threatening|JJ|O lung|lung|NN|O disorders|disorder|NNS|O ,|,|,|O for|for|IN|O which|which|WDT|O no|no|DT|O effective|effective|JJ|O treatment|treatment|NN|O option|option|NN|O exists|exist|VBZ|O .|.|.|O 
In|in|IN|O view|view|NN|O of|of|IN|O IPF|IPF|NN|O ,|,|,|O the|the|DT|O American|american|NNP|O Thoracic|Thoracic|NNP|O Society|society|NNP|O (|(|(|O ATS|ATS|NNS|O )|)|)|O /|/|:|O European|european|JJ|O Respiratory|respiratory|JJ|O Society|society|NN|O (|(|(|O ERS|ERS|NNS|O )|)|)|O consensus|consensus|NN|O statement|statement|NN|O recommends|recommend|VBZ|O a|a|DT|O combined|combined|JJ|O therapy|therapy|NN|O with|with|IN|O corticosteroids|corticosteroid|NNS|O and|and|CC|O azathioprine|azathioprine|NN|O or|or|CC|O cyclophosphamide|cyclophosphamide|NN|O ,|,|,|O although|although|IN|O data|datum|NNS|O from|from|IN|O conclusive|conclusive|JJ|O clinical|clinical|JJ|O trials|trial|NNS|O are|be|VBP|O yet|yet|RB|O missing|miss|VBG|O and|and|CC|O the|the|DT|O recurrent|recurrent|JJ|O clinical|clinical|JJ|O experience|experience|NN|O is|be|VBZ|O that|that|IN|O these|these|DT|O drugs|drug|NNS|O do|do|VBP|O not|not|RB|O really|real|RB|O help|help|VB|O in|in|IN|O IPF|IPF|NN|O .|.|.|O 
Up|up|IN|O to|to|TO|O now|now|RB|O ,|,|,|O lung|lung|NN|O transplantation|transplantation|NN|O represents|represent|VBZ|O the|the|DT|O last|last|JJ|O and|and|CC|O only|only|RB|O therapeutic|therapeutic|JJ|O option|option|NN|O for|for|IN|O IPF|IPF|NN|O subjects|subject|NNS|O .|.|.|O 
Based|base|VBN|O on|on|IN|O new|new|JJ|O pathophysiological|pathophysiological|JJ|O concepts|concept|NNS|O of|of|IN|O IPF|IPF|NN|O ,|,|,|O there|there|EX|O are|be|VBP|O meanwhile|meanwhile|RB|O a|a|DT|O couple|couple|NN|O of|of|IN|O different|different|JJ|O agents|agent|NNS|O under|under|IN|O preclinical|preclinical|JJ|O and|and|CC|O clinical|clinical|JJ|O assessment|assessment|NN|O ,|,|,|O and|and|CC|O the|the|DT|O increasing|increase|VBG|O number|number|NN|O of|of|IN|O clinical|clinical|JJ|O trials|trial|NNS|O ongoing|ongoing|JJ|O in|in|IN|O IPF|IPF|NNP|O raise|raise|VB|O the|the|DT|O hope|hope|NN|O that|that|IN|O an|a|DT|O effective|effective|JJ|O treatment|treatment|NN|O comes|come|VBZ|O into|into|IN|O reach|reach|NN|O .|.|.|O 
The|the|DT|O agents|agent|NNS|O investigated|investigate|VBN|O and|and|CC|O their|their|PRP$|O targets|target|NNS|O are|be|VBP|O :|:|:|O acetylcysteine|acetylcysteine|NN|O (|(|(|O reactive|reactive|JJ|O oxygen|oxygen|NN|O species|specie|NNS|O [|[|(|O ROS|ros|NN|O ]|]|)|O scavenging|scavenging|NN|O )|)|)|O ,|,|,|O interferon-gamma|interferon-gamma|NN|O 1b|1b|NN|O (|(|(|O modulation|modulation|NN|O of|of|IN|O Th1/Th2|Th1/Th2|NN|O balance|balance|NN|O ,|,|,|O direct|direct|JJ|O antifibrotic|antifibrotic|JJ|O effects|effect|NNS|O )|)|)|O ,|,|,|O pirfenidone|pirfenidone|NN|O and|and|CC|O GC|gc|NN|O 1008|1008|CD|O (|(|(|O blockade|blockade|NN|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE )|)|)|O ,|,|,|O FG|FG|NN|O 3019|3019|CD|O (|(|(|O blockade|blockade|NN|O of|of|IN|O connective|connective|NN|GENE tissue|tissue|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE )|)|)|O ,|,|,|O imatinib|imatinib|NN|O mesylate|mesylate|NN|O (|(|(|O blockade|blockade|NN|O of|of|IN|O platelet-derived|platelet-derived|JJ|O growth|growth|NN|O factor|factor|NN|O )|)|)|O ,|,|,|O bosentan|bosentan|NN|O (|(|(|O blockade|blockade|NN|O of|of|IN|O endothelin|endothelin|NN|O )|)|)|O ,|,|,|O zileutin|zileutin|NN|O (|(|(|O blockade|blockade|NN|O of|of|IN|O leukotrienes|leukotriene|NNS|O )|)|)|O ,|,|,|O etanercept|Etanercept|NN|O (|(|(|O blockade|blockade|NN|O of|of|IN|O tumor|tumor|NN|GENE necrosis|necrosis|NN|GENE factor|factor|NN|GENE alpha|alpha|NN|GENE )|)|)|O ,|,|,|O heparin|heparin|NN|O (|(|(|O alveolar|alveolar|JJ|O anticoagulation|anticoagulation|NN|O )|)|)|O .|.|.|O 
Hopefully|hopeful|RB|O ,|,|,|O these|these|DT|O new|new|JJ|O therapeutic|therapeutic|JJ|O strategies|strategy|NNS|O may|may|MD|O help|help|VB|O to|to|TO|O improve|improve|VB|O prognosis|prognosis|NN|O of|of|IN|O IPF|IPF|NN|O in|in|IN|O the|the|DT|O future|future|NN|O .|.|.|O 
Targeting|Targeting|NN|O genes|gene|NNS|O for|for|IN|O treatment|treatment|NN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O :|:|:|O challenges|challenge|NNS|O and|and|CC|O opportunities|opportunity|NNS|O ,|,|,|O promises|promise|NNS|O and|and|CC|O pitfalls|pitfall|NNS|O .|.|.|O 
The|the|DT|O currently|current|RB|O accepted|accept|VBN|O approach|approach|NN|O to|to|TO|O treatment|treatment|NN|O of|of|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O based|base|VBN|O on|on|IN|O the|the|DT|O assumption|assumption|NN|O that|that|IN|O it|it|PRP|O is|be|VBZ|O a|a|DT|O chronic|chronic|JJ|O inflammatory|inflammatory|JJ|O disease|disease|NN|O ,|,|,|O and|and|CC|O most|many|JJS|O available|available|JJ|O antiinflammatory|antiinflammatory|JJ|O drugs|drug|NNS|O target|target|VBP|O numerous|numerous|JJ|O biological|biological|JJ|O processes|process|NNS|O involving|involve|VBG|O multiple|multiple|JJ|O genes|gene|NNS|O ,|,|,|O but|but|CC|O are|be|VBP|O not|not|RB|O often|often|RB|O beneficial|beneficial|JJ|O .|.|.|O 
More|much|RBR|O novel|novel|JJ|O therapeutic|therapeutic|JJ|O strategies|strategy|NNS|O take|take|VBP|O recent|recent|JJ|O findings|finding|NNS|O about|about|IN|O the|the|DT|O underlying|underlie|VBG|O molecular|molecular|JJ|O mechanisms|mechanism|NNS|O of|of|IN|O fibrogenesis|fibrogenesis|NN|O into|into|IN|O account|account|NN|O ,|,|,|O and|and|CC|O ongoing|ongoing|JJ|O and|and|CC|O as|as|RB|O yet|yet|RB|O unpublished|unpublished|JJ|O clinical|clinical|JJ|O trials|trial|NNS|O in|in|IN|O IPF|IPF|NN|O aim|aim|NN|O to|to|TO|O block|block|VB|O single|single|JJ|O gene|gene|NN|O targets|target|VBZ|O believed|believe|VBN|O to|to|TO|O play|play|VB|O major|major|JJ|O roles|role|NNS|O in|in|IN|O disease|disease|NN|O progression|progression|NN|O .|.|.|O 
Characterization|characterization|NN|O of|of|IN|O the|the|DT|O mechanisms|mechanism|NNS|O involved|involve|VBN|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O IPF|IPF|NN|O has|have|VBZ|O largely|large|RB|O come|come|VBN|O from|from|IN|O the|the|DT|O use|use|NN|O of|of|IN|O animal|animal|NN|O disease|disease|NN|O models|model|NNS|O in|in|IN|O rodents|rodent|NNS|O .|.|.|O 
Most|many|JJS|O data|datum|NNS|O suggest|suggest|VBP|O ,|,|,|O from|from|IN|O among|among|IN|O the|the|DT|O different|different|JJ|O factors|factor|NNS|O ,|,|,|O a|a|DT|O prominent|prominent|JJ|O role|role|NN|O for|for|IN|O the|the|DT|O transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta1|beta1|NN|O and|and|CC|O platelet-derived|platelet-derived|JJ|O growth|growth|NN|O factor|factor|NN|O pathways|pathway|NNS|O .|.|.|O 
Inflammation|inflammation|NN|O is|be|VBZ|O a|a|DT|O critical|critical|JJ|O element|element|NN|O of|of|IN|O the|the|DT|O initiation|initiation|NN|O of|of|IN|O fibrosis|fibrosis|NN|O and|and|CC|O data|datum|NNS|O indicate|indicate|VBP|O that|that|IN|O the|the|DT|O Smad|SMAD|NN|O pathway|pathway|NN|O is|be|VBZ|O a|a|DT|O necessary|necessary|JJ|O link|link|NN|O to|to|TO|O fibrosis|fibrosis|NN|O through|through|IN|O TGF-beta|TGF-beta|NN|GENE and|and|CC|O Smad3|Smad3|NN|GENE signaling|signaling|NN|O ,|,|,|O which|which|WDT|O introduces|introduce|VBZ|O matrix|matrix|NN|O regulation|regulation|NN|O as|as|IN|O a|a|DT|O new|new|JJ|O target|target|NN|O for|for|IN|O therapeutic|therapeutic|JJ|O intervention|intervention|NN|O .|.|.|O 
Regardless|regardless|RB|O ,|,|,|O gene|gene|NN|O targeted|target|VBN|O therapy|therapy|NN|O has|have|VBZ|O numerous|numerous|JJ|O pitfalls|pitfall|NNS|O that|that|WDT|O have|have|VBP|O to|to|TO|O be|be|VB|O addressed|address|VBN|O before|before|IN|O we|we|PRP|O see|see|VBP|O a|a|DT|O real|real|JJ|O therapeutic|therapeutic|JJ|O advance|advance|NN|O .|.|.|O 
RhoA|RHOA|NN|GENE signaling|signaling|NN|O modulates|modulate|VBZ|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE expression|expression|NN|O in|in|IN|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ;|;|:|O implications|implication|NNS|O for|for|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
BACKGROUND|background|NN|O :|:|:|O Idiopathic|idiopathic|JJ|O Pulmonary|pulmonary|JJ|O Fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O debilitating|debilitating|JJ|O disease|disease|NN|O characterized|characterize|VBN|O by|by|IN|O exaggerated|exaggerated|JJ|O extracellular|extracellular|JJ|O matrix|matrix|NN|O deposition|deposition|NN|O and|and|CC|O aggressive|aggressive|JJ|O lung|lung|NN|O structural|structural|JJ|O remodeling|remodeling|NN|O .|.|.|O 
Disease|disease|NN|O pathogenesis|pathogenesis|NN|O is|be|VBZ|O driven|drive|VBN|O by|by|IN|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O formation|formation|NN|O ,|,|,|O consequent|consequent|JJ|O on|on|IN|O growth|growth|NN|O factor|factor|NN|O overexpression|overexpression|NN|O and|and|CC|O myofibroblast|myofibroblast|NN|O proliferation|proliferation|NN|O .|.|.|O 
We|we|PRP|O have|have|VBP|O previously|previous|RB|O shown|show|VBN|O that|that|IN|O both|both|CC|O CTGF|Ctgf|NN|GENE overexpression|overexpression|NN|O and|and|CC|O myofibroblast|myofibroblast|NN|O formation|formation|NN|O in|in|IN|O IPF|IPF|NN|O cell|cell|NN|O lines|line|NNS|O are|be|VBP|O dependent|dependent|JJ|O on|on|IN|O RhoA|RHOA|NN|GENE signaling|signaling|NN|O .|.|.|O 
As|as|IN|O RhoA-mediated|rhoa-mediated|JJ|O regulation|regulation|NN|O is|be|VBZ|O also|also|RB|O involved|involve|VBN|O in|in|IN|O cell|cell|NN|O cycle|cycle|NN|O progression|progression|NN|O ,|,|,|O we|we|PRP|O hypothesise|hypothesise|VBP|O that|that|IN|O this|this|DT|O pathway|pathway|NN|O is|be|VBZ|O key|key|JJ|O to|to|TO|O lung|lung|NN|O fibroblast|fibroblast|NN|O turnover|turnover|NN|O through|through|IN|O modulation|modulation|NN|O of|of|IN|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE kinetic|kinetic|JJ|O expression|expression|NN|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O Cyclin|cyclin|NN|O D1|D1|NN|O expression|expression|NN|O was|be|VBD|O compared|compare|VBN|O in|in|IN|O primary|primary|JJ|O IPF|IPF|NN|O patient-derived|patient-derived|JJ|O fibroblasts|fibroblast|NNS|O and|and|CC|O equivalent|equivalent|JJ|O normal|normal|JJ|O control|control|NN|O cells|cell|NNS|O .|.|.|O 
Quantitative|quantitative|JJ|O real|real|JJ|O time|time|NN|O PCR|pcr|NN|O was|be|VBD|O employed|employ|VBN|O to|to|TO|O examine|examine|VB|O relative|relative|JJ|O expression|expression|NN|O levels|level|NNS|O of|of|IN|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE mRNA|mRNA|NN|O ;|;|:|O protein|protein|NN|O expression|expression|NN|O was|be|VBD|O confirmed|confirm|VBN|O by|by|IN|O western|western|NN|O blotting|blotting|NN|O .|.|.|O 
Effects|effect|NNS|O of|of|IN|O Rho|rho|NN|O signaling|signaling|NN|O were|be|VBD|O investigated|investigate|VBN|O using|use|VBG|O transient|transient|JJ|O transfection|transfection|NN|O of|of|IN|O constitutively|constitutive|RB|O active|active|JJ|O and|and|CC|O dominant|dominant|JJ|O negative|negative|JJ|O RhoA|RHOA|NN|GENE constructs|construct|NNS|O as|as|RB|O well|well|RB|O as|as|IN|O pharmacological|pharmacological|JJ|O inhibitors|inhibitor|NNS|O .|.|.|O 
Cellular|cellular|JJ|O proliferation|proliferation|NN|O of|of|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O was|be|VBD|O determined|determine|VBN|O by|by|IN|O BrdU|brdu|NN|O incorporation|incorporation|NN|O ELISA|elisa|NN|O .|.|.|O 
To|to|TO|O further|further|RB|O explore|explore|VB|O RhoA|RHOA|NN|GENE regulation|regulation|NN|O of|of|IN|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE in|in|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O and|and|CC|O associated|associate|VBN|O cell|cell|NN|O cycle|cycle|NN|O progression|progression|NN|O ,|,|,|O an|a|DT|O established|established|JJ|O Rho|rho|NN|O inhibitor|inhibitor|NN|O ,|,|,|O Simvastatin|simvastatin|NNP|O ,|,|,|O was|be|VBD|O incorporated|incorporate|VBN|O in|in|IN|O our|our|PRP$|O studies|study|NNS|O .|.|.|O 
RESULTS|result|NNS|O :|:|:|O Cyclin|cyclin|NN|O D1|D1|NN|O expression|expression|NN|O was|be|VBD|O upregulated|upregulate|VBN|O in|in|IN|O IPF|IPF|NN|O compared|compare|VBN|O to|to|TO|O normal|normal|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O under|under|IN|O exponential|exponential|JJ|O growth|growth|NN|O conditions|condition|NNS|O (|(|(|O p|p|NN|O <|<|JJR|O 0.05|0.05|CD|O )|)|)|O .|.|.|O 
Serum|serum|NN|O deprivation|deprivation|NN|O inhibited|inhibit|VBD|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE expression|expression|NN|O ,|,|,|O which|which|WDT|O was|be|VBD|O restored|restore|VBN|O following|follow|VBG|O treatment|treatment|NN|O with|with|IN|O fibrogenic|fibrogenic|JJ|O growth|growth|NN|O factors|factor|NNS|O (|(|(|O TGF-beta1|TGF-beta1|NN|GENE and|and|CC|O CTGF|Ctgf|NN|GENE )|)|)|O .|.|.|O 
RhoA|RHOA|NN|GENE inhibition|inhibition|NN|O ,|,|,|O using|use|VBG|O a|a|DT|O dominant|dominant|JJ|O negative|negative|JJ|O mutant|mutant|NN|O and|and|CC|O a|a|DT|O pharmacological|pharmacological|JJ|O inhibitor|inhibitor|NN|O (|(|(|O C3|C3|NN|O exotoxin|exotoxin|NN|O )|)|)|O ,|,|,|O suppressed|suppress|VBD|O levels|level|NNS|O of|of|IN|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE mRNA|mRNA|NN|O and|and|CC|O protein|protein|NN|O in|in|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O with|with|IN|O significant|significant|JJ|O abrogation|abrogation|NN|O of|of|IN|O cell|cell|NN|O turnover|turnover|NN|O (|(|(|O p|p|NN|O <|<|JJR|O 0.05|0.05|CD|O )|)|)|O .|.|.|O 
Furthermore|furthermore|RB|O ,|,|,|O Simvastatin|simvastatin|NNP|O dose-dependently|dose-dependent|RB|O inhibited|inhibit|VBD|O fibroblast|fibroblast|NN|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE gene|gene|NN|O and|and|CC|O protein|protein|NN|O expression|expression|NN|O ,|,|,|O inducing|induce|VBG|O G1|G1|NN|O cell|cell|NN|O cycle|cycle|NN|O arrest|arrest|NN|O .|.|.|O 
Similar|similar|JJ|O trends|trend|NNS|O were|be|VBD|O observed|observe|VBN|O in|in|IN|O control|control|NN|O experiments|experiment|NNS|O using|use|VBG|O normal|normal|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O though|though|IN|O exhibited|exhibit|VBD|O responses|response|NNS|O were|be|VBD|O lower|low|JJR|O in|in|IN|O magnitude|magnitude|NN|O .|.|.|O 
CONCLUSION|conclusion|NN|O :|:|:|O These|these|DT|O findings|finding|NNS|O report|report|VBP|O for|for|IN|O the|the|DT|O first|first|JJ|O time|time|NN|O that|that|WDT|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE expression|expression|NN|O is|be|VBZ|O deregulated|deregulate|VBN|O in|in|IN|O IPF|IPF|NN|O through|through|IN|O a|a|DT|O RhoA|RHOA|NN|GENE dependent|dependent|JJ|O mechanism|mechanism|NN|O that|that|WDT|O influences|influence|VBZ|O lung|lung|NN|O fibroblast|fibroblast|NN|O proliferation|proliferation|NN|O .|.|.|O 
This|this|DT|O potentially|potential|RB|O unravels|unravel|VBZ|O new|new|JJ|O molecular|molecular|JJ|O targets|target|NNS|O for|for|IN|O future|future|JJ|O anti-IPF|anti-ipf|JJ|O strategies|strategy|NNS|O ;|;|:|O accordingly|according|RB|O ,|,|,|O Simvastatin|simvastatin|NN|O inhibition|inhibition|NN|O of|of|IN|O Rho-mediated|rho-mediated|JJ|O cyclin|cyclin|NN|GENE D1|D1|NN|GENE expression|expression|NN|O in|in|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O merits|merit|NNS|O further|further|RB|O exploitation|exploitation|NN|O .|.|.|O 
Pirfenidone|Pirfenidone|NNP|O for|for|IN|O the|the|DT|O treatment|treatment|NN|O of|of|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O an|a|DT|O under-recognised|under-recognised|JJ|O ,|,|,|O rare|rare|JJ|O ,|,|,|O progressive|progressive|JJ|O disease|disease|NN|O of|of|IN|O the|the|DT|O lungs|lung|NNS|O with|with|IN|O unknown|unknown|JJ|O aetiology|aetiology|NN|O and|and|CC|O high|high|JJ|O mortality|mortality|NN|O .|.|.|O 
The|the|DT|O currently|current|RB|O advocated|advocate|VBN|O pathogenic|pathogenic|JJ|O mechanism|mechanism|NN|O is|be|VBZ|O represented|represent|VBN|O by|by|IN|O progressive|progressive|JJ|O multifocal|multifocal|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
It|it|PRP|O is|be|VBZ|O diagnosed|diagnose|VBN|O based|base|VBN|O on|on|IN|O clinical|clinical|JJ|O ,|,|,|O radiographic|radiographic|JJ|O ,|,|,|O physiological|physiological|JJ|O and|and|CC|O histopathological|histopathological|JJ|O criteria|criterion|NNS|O .|.|.|O 
Existing|exist|VBG|O therapeutic|therapeutic|JJ|O guidelines|guideline|NNS|O recommend|recommend|VBP|O anti-inflammatory|anti-inflammatory|JJ|O and|and|CC|O immunosuppressive|immunosuppressive|JJ|O combinations|combination|NNS|O ,|,|,|O despite|despite|IN|O proven|proven|JJ|O limited|limited|JJ|O efficacy|efficacy|NN|O .|.|.|O 
There|there|EX|O is|be|VBZ|O no|no|DT|O therapy|therapy|NN|O approved|approve|VBD|O specifically|specific|RB|O for|for|IN|O IPF|IPF|NN|O ,|,|,|O but|but|CC|O several|several|JJ|O antifibrotic|antifibrotic|JJ|O agents|agent|NNS|O are|be|VBP|O currently|current|RB|O under|under|IN|O development|development|NN|O for|for|IN|O this|this|DT|O indication|indication|NN|O .|.|.|O 
Pirfenidone|Pirfenidone|NNP|O is|be|VBZ|O an|a|DT|O antifibrotic|antifibrotic|JJ|O agent|agent|NN|O potentially|potential|RB|O effective|effective|JJ|O for|for|IN|O IPF|IPF|NN|O therapy|therapy|NN|O ,|,|,|O and|and|CC|O preclinical|preclinical|JJ|O and|and|CC|O available|available|JJ|O clinical|clinical|JJ|O data|datum|NNS|O support|support|VBP|O its|its|PRP$|O use|use|NN|O in|in|IN|O IPF|IPF|NN|O .|.|.|O 
Future|future|JJ|O clinical|clinical|JJ|O studies|study|NNS|O are|be|VBP|O expected|expect|VBN|O to|to|TO|O provide|provide|VB|O more|many|JJR|O consistent|consistent|JJ|O information|information|NN|O on|on|IN|O survival|survival|NN|O benefit|benefit|NN|O ,|,|,|O lung|lung|NN|O function|function|NN|O and|and|CC|O health-related|health-related|JJ|O quality|quality|NN|O of|of|IN|O life|life|NN|O .|.|.|O 
Bone|bone|NN|O morphogenetic|morphogenetic|JJ|O protein-4|protein-4|NN|O inhibitor|inhibitor|NN|O gremlin|gremlin|NN|GENE is|be|VBZ|O overexpressed|overexpress|VBN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O ie|ie|FW|O ,|,|,|O usual|usual|JJ|O interstitial|interstitial|JJ|O pneumonia|pneumonia|NN|O in|in|IN|O histopathology|histopathology|NN|O ,|,|,|O is|be|VBZ|O a|a|DT|O disease|disease|NN|O characterized|characterize|VBN|O by|by|IN|O tissue|tissue|NN|O destruction|destruction|NN|O and|and|CC|O active|active|JJ|O areas|area|NNS|O of|of|IN|O fibroproliferation|fibroproliferation|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O .|.|.|O 
Gremlin|gremlin|NNP|GENE (|(|(|O Drm|drm|NNP|O )|)|)|O ,|,|,|O a|a|DT|O member|member|NN|O of|of|IN|O the|the|DT|O cysteine|cysteine|NN|O knot|knot|NN|O family|family|NN|O of|of|IN|O bone|bone|NN|GENE morphogenetic|morphogenetic|NN|GENE protein|protein|NN|GENE (|(|(|O BMP|BMP|NN|GENE )|)|)|O inhibitors|inhibitor|NNS|O ,|,|,|O functions|function|VBZ|O to|to|TO|O antagonize|antagonize|VB|O BMP-4-mediated|bmp-4-mediated|JJ|O signals|signal|NNS|O during|during|IN|O lung|lung|NN|O development|development|NN|O .|.|.|O 
We|we|PRP|O describe|describe|VBP|O here|here|RB|O consistent|consistent|JJ|O overexpression|overexpression|NN|O of|of|IN|O gremlin|gremlin|NN|GENE in|in|IN|O the|the|DT|O lung|lung|NN|O interstitium|interstitium|NN|O of|of|IN|O IPF|IPF|NN|O patients|patient|NNS|O .|.|.|O 
Quantitative|quantitative|JJ|O real-time|real-time|JJ|O reverse|reverse|JJ|O transcriptase-polymerase|transcriptase-polymerase|NN|O chain|chain|NN|O reaction|reaction|NN|O analyses|analysis|NNS|O revealed|reveal|VBD|O considerably|considerable|RB|O higher|high|JJR|O levels|level|NNS|O of|of|IN|O gremlin|gremlin|NN|GENE mRNA|mRNA|NN|O in|in|IN|O lung|lung|NN|O biopsies|biopsy|NNS|O from|from|IN|O IPF|IPF|NN|O patients|patient|NNS|O ,|,|,|O the|the|DT|O highest|high|JJS|O level|level|NN|O being|be|VBG|O 35-fold|35-fold|JJ|O higher|high|JJR|O compared|compare|VBN|O to|to|TO|O controls|control|NNS|O .|.|.|O 
Lung|lung|NN|O fibroblasts|fibroblast|NNS|O isolated|isolate|VBN|O from|from|IN|O IPF|IPF|NN|O patients|patient|NNS|O also|also|RB|O expressed|express|VBD|O elevated|elevated|JJ|O levels|level|NNS|O of|of|IN|O gremlin|gremlin|NN|GENE ,|,|,|O which|which|WDT|O was|be|VBD|O associated|associate|VBN|O with|with|IN|O impaired|impaired|JJ|O responsiveness|responsiveness|NN|O to|to|TO|O endogenous|endogenous|JJ|O and|and|CC|O exogenous|exogenous|JJ|O BMP-4|BMP-4|NN|O .|.|.|O 
Transforming-growth-factor-beta-induced|transforming-growth-factor-beta-induced|JJ|O epithelial-to-mesenchymal|epithelial-to-mesenchymal|JJ|O transition|transition|NN|O of|of|IN|O A549|A549|NN|O lung|lung|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O in|in|IN|O culture|culture|NN|O was|be|VBD|O also|also|RB|O associated|associate|VBN|O with|with|IN|O induction|induction|NN|O of|of|IN|O gremlin|gremlin|NN|GENE mRNA|mRNA|NN|O expression|expression|NN|O .|.|.|O 
In|in|IN|O addition|addition|NN|O ,|,|,|O A549|A549|NN|O cells|cell|NNS|O transfected|transfect|VBN|O to|to|TO|O overexpress|overexpress|VB|O gremlin|gremlin|NN|GENE were|be|VBD|O more|much|RBR|O susceptible|susceptible|JJ|O to|to|TO|O transforming-growth-factor-beta-induced|transforming-growth-factor-beta-induced|JJ|O epithelial-to-mesenchymal|epithelial-to-mesenchymal|JJ|O transition|transition|NN|O .|.|.|O 
Gremlin-mediated|gremlin-mediated|JJ|O inhibition|inhibition|NN|O of|of|IN|O BMP-4|BMP-4|NN|O signaling|signaling|NN|O pathways|pathway|NNS|O is|be|VBZ|O likely|likely|JJ|O to|to|TO|O enhance|enhance|VB|O the|the|DT|O fibrotic|fibrotic|JJ|O response|response|NN|O and|and|CC|O reduce|reduce|VB|O epithelial|epithelial|JJ|O regeneration|regeneration|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O .|.|.|O 
The|the|DT|O overexpression|overexpression|NN|O of|of|IN|O this|this|DT|O developmental|developmental|JJ|O gene|gene|NN|O in|in|IN|O IPF|IPF|NN|O may|may|MD|O be|be|VB|O a|a|DT|O key|key|JJ|O event|event|NN|O in|in|IN|O the|the|DT|O persistence|persistence|NN|O of|of|IN|O myofibroblasts|myofibroblast|NNS|O in|in|IN|O the|the|DT|O lung|lung|NN|O interstitium|interstitium|NN|O and|and|CC|O provides|provide|VBZ|O a|a|DT|O potential|potential|JJ|O target|target|NN|O for|for|IN|O therapeutic|therapeutic|JJ|O intervention|intervention|NN|O .|.|.|O 
Thalidomide|thalidomide|NNP|O reduces|reduce|VBZ|O IL-18|IL-18|NN|GENE ,|,|,|O IL-8|IL-8|NN|GENE and|and|CC|O TNF-alpha|TNF-alpha|NN|GENE release|release|NN|O from|from|IN|O alveolar|alveolar|JJ|O macrophages|macrophage|NNS|O in|in|IN|O interstitial|interstitial|JJ|O lung|lung|NN|O disease|disease|NN|O .|.|.|O 
Thalidomide|thalidomide|NN|O exhibits|exhibit|VBZ|O diverse|diverse|JJ|O actions|action|NNS|O of|of|IN|O anti-inflammation|anti-inflammation|JJ|O ,|,|,|O immunomodulation|immunomodulation|NN|O and|and|CC|O anti-angiogenesis|anti-angiogenesis|NN|O .|.|.|O 
The|the|DT|O efficacy|efficacy|NN|O of|of|IN|O thalidomide|thalidomide|NN|O treatment|treatment|NN|O in|in|IN|O sarcoidosis|sarcoidosis|NN|O with|with|IN|O lupus|lupus|NN|O pernio|pernio|NN|O is|be|VBZ|O thought|think|VBN|O to|to|TO|O be|be|VB|O due|due|JJ|O to|to|TO|O inhibition|inhibition|NN|O of|of|IN|O tumour|tumour|NN|O necrosis|necrosis|NN|O factor|factor|NN|O (|(|(|O TNF|TNF|NN|O )|)|)|O -|-|:|O alpha|alpha|NN|O .|.|.|O 
The|the|DT|O mechanisms|mechanism|NNS|O that|that|WDT|O underlie|underlie|VBP|O the|the|DT|O properties|property|NNS|O of|of|IN|O thalidomide|thalidomide|NN|O are|be|VBP|O still|still|RB|O unclear|unclear|JJ|O in|in|IN|O interstitial|interstitial|JJ|O lung|lung|NN|O disease|disease|NN|O .|.|.|O 
The|the|DT|O current|current|JJ|O authors|author|NNS|O investigated|investigate|VBD|O the|the|DT|O potential|potential|JJ|O inhibitory|inhibitory|JJ|O effects|effect|NNS|O of|of|IN|O thalidomide|thalidomide|NN|O at|at|IN|O concentrations|concentration|NNS|O of|of|IN|O 0.1|0.1|CD|O ,|,|,|O 0.01|0.01|CD|O and|and|CC|O 0.001|0.001|CD|O mM|mm|NN|O on|on|IN|O the|the|DT|O production|production|NN|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE ,|,|,|O TNF-alpha|TNF-alpha|NN|GENE ,|,|,|O interleukin|interleukin|NN|O (|(|(|O IL|IL|NN|O )|)|)|O -1|-1|CD|O beta|beta|NN|O ,|,|,|O IL-6|IL-6|NN|GENE ,|,|,|O IL-8|IL-8|NN|GENE ,|,|,|O IL-10|IL-10|NN|GENE ,|,|,|O IL-12p70|IL-12p70|NN|O ,|,|,|O IL-12p40|IL-12p40|NN|O and|and|CC|O IL-18|IL-18|NN|GENE by|by|IN|O alveolar|alveolar|JJ|O macrophages|macrophage|NNS|O from|from|IN|O bronchoalveolar|bronchoalveolar|JJ|O lavage|lavage|NN|O in|in|IN|O patients|patient|NNS|O with|with|IN|O sarcoidosis|sarcoidosis|NN|O (|(|(|O n|n|NN|O =|=|JJ|O 8|8|CD|O )|)|)|O ,|,|,|O hypersensitivity|hypersensitivity|NN|O pneumonitis|pneumonitis|NN|O (|(|(|O HP|hp|NNP|O ;|;|:|O n|n|NN|O =|=|JJ|O 8|8|CD|O )|)|)|O and|and|CC|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O ;|;|:|O n|n|NN|O =|=|JJ|O 12|12|CD|O )|)|)|O .|.|.|O 
In|in|IN|O sarcoidosis|sarcoidosis|NN|O and|and|CC|O HP|hp|NNP|O patients|patient|NNS|O ,|,|,|O thalidomide|thalidomide|NN|O induced|induce|VBD|O a|a|DT|O dose-dependent|dose-dependent|JJ|O ,|,|,|O partial|partial|JJ|O suppression|suppression|NN|O of|of|IN|O lipopolysacchride|lipopolysacchride|NN|O (|(|(|O LPS|LPS|NN|O )|)|)|O -|-|:|O stimulated|stimulate|VBN|O TNF-alpha|TNF-alpha|NN|GENE ,|,|,|O IL-12p40|IL-12p40|NN|O and|and|CC|O IL-18|IL-18|NN|GENE release|release|NN|O .|.|.|O 
At|at|IN|O the|the|DT|O highest|high|JJS|O thalidomide|thalidomide|NN|O concentration|concentration|NN|O (|(|(|O 0.1|0.1|CD|O mM|mm|NN|O )|)|)|O ,|,|,|O LPS-stimulated|lps-stimulated|JJ|O IL-8|IL-8|NN|GENE production|production|NN|O was|be|VBD|O also|also|RB|O suppressed|suppress|VBN|O .|.|.|O 
In|in|IN|O IPF|IPF|NN|O patients|patient|NNS|O ,|,|,|O although|although|IN|O spontaneous|spontaneous|JJ|O production|production|NN|O of|of|IN|O TNF-alpha|TNF-alpha|NN|GENE ,|,|,|O IL-12p40|IL-12p40|NN|O ,|,|,|O IL-18|IL-18|NN|GENE and|and|CC|O IL-8|IL-8|NN|GENE was|be|VBD|O lower|low|JJR|O than|than|IN|O in|in|IN|O sarcoidosis|sarcoidosis|NN|O and|and|CC|O HP|hp|NNP|O patients|patient|NNS|O ,|,|,|O with|with|IN|O LPS|LPS|NN|O stimulation|stimulation|NN|O the|the|DT|O cytokines|cytokine|NNS|O were|be|VBD|O significantly|significant|RB|O elevated|elevated|JJ|O and|and|CC|O also|also|RB|O partially|partial|RB|O inhibited|inhibit|VBN|O by|by|IN|O thalidomide|thalidomide|NN|O .|.|.|O 
In|in|IN|O conclusion|conclusion|NN|O ,|,|,|O thalidomide|thalidomide|NN|O has|have|VBZ|O the|the|DT|O potential|potential|JJ|O to|to|TO|O improve|improve|VB|O the|the|DT|O therapeutic|therapeutic|JJ|O regimens|regimen|NNS|O for|for|IN|O sarcoidosis|sarcoidosis|NN|O ,|,|,|O hypersensitivity|hypersensitivity|NN|O pneumonitis|pneumonitis|NN|O and|and|CC|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O by|by|IN|O reducing|reduce|VBG|O tumour|tumour|NN|O necrosis|necrosis|NN|O factor-alpha|factor-alpha|NN|O ,|,|,|O interleukin-12p40|interleukin-12p40|NN|O ,|,|,|O interleukin-18|interleukin-18|NN|O and|and|CC|O interleukin-8|interleukin-8|NN|GENE production|production|NN|O .|.|.|O 
Extracellular|extracellular|JJ|O superoxide|superoxide|NN|O dismutase|dismutase|NN|O has|have|VBZ|O a|a|DT|O highly|high|RB|O specific|specific|JJ|O localization|localization|NN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis/usual|fibrosis/usual|JJ|O interstitial|interstitial|JJ|O pneumonia|pneumonia|NN|O .|.|.|O 
AIMS|aim|NNS|O :|:|:|O Recent|recent|JJ|O studies|study|NNS|O suggest|suggest|VBP|O the|the|DT|O importance|importance|NN|O of|of|IN|O oxidant|oxidant|JJ|O stress|stress|NN|O in|in|IN|O the|the|DT|O progression|progression|NN|O of|of|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
The|the|DT|O aim|aim|NN|O of|of|IN|O this|this|DT|O study|study|NN|O was|be|VBD|O to|to|TO|O investigate|investigate|VB|O extracellular|extracellular|NN|GENE superoxide|superoxide|NN|GENE dismutase|dismutase|NN|GENE (|(|(|O ECSOD|ECSOD|NN|GENE )|)|)|O ,|,|,|O the|the|DT|O major|major|JJ|O antioxidant|antioxidant|JJ|O enzyme|enzyme|NN|O of|of|IN|O the|the|DT|O extracellular|extracellular|JJ|O matrix|matrix|NN|O of|of|IN|O human|human|JJ|O lung|lung|NN|O ,|,|,|O in|in|IN|O biopsy-proven|biopsy-proven|JJ|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O related|related|JJ|O to|to|TO|O usual|usual|JJ|O interstitial|interstitial|JJ|O pneumonia|pneumonia|NN|O (|(|(|O UIP|UIP|NN|O )|)|)|O .|.|.|O 
METHODS|method|NNS|O AND|and|CC|O RESULTS|result|NNS|O :|:|:|O Fibrotic|fibrotic|JJ|O areas|area|NNS|O and|and|CC|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O in|in|IN|O UIP|UIP|NNP|O lungs|lung|NNS|O were|be|VBD|O notable|notable|JJ|O for|for|IN|O absence|absence|NN|O of|of|IN|O ECSOD|ECSOD|NN|GENE by|by|IN|O immunohistochemistry|immunohistochemistry|NN|O .|.|.|O 
Western|western|NN|O blotting|blotting|NN|O showed|show|VBD|O significantly|significant|RB|O lowered|lowered|JJ|O immunoreactivity|immunoreactivity|NN|O of|of|IN|O ECSOD|ECSOD|NN|GENE in|in|IN|O fibrotic|fibrotic|JJ|O compared|compare|VBN|O with|with|IN|O non-fibrotic|non-fibrotic|JJ|O areas|area|NNS|O of|of|IN|O the|the|DT|O diseased|diseased|JJ|O lung|lung|NN|O .|.|.|O 
The|the|DT|O only|only|JJ|O cell|cell|NN|O type|type|NN|O that|that|WDT|O showed|show|VBD|O intense|intense|JJ|O ECSOD|ECSOD|NN|GENE positivity|positivity|NN|O in|in|IN|O UIP|UIP|NNP|O was|be|VBD|O the|the|DT|O interstitial|interstitial|JJ|O mast|mast|NN|O cell|cell|NN|O .|.|.|O 
In|in|IN|O order|order|NN|O to|to|TO|O investigate|investigate|VB|O the|the|DT|O mechanism|mechanism|NN|O for|for|IN|O ECSOD|ECSOD|NN|GENE depletion|depletion|NN|O in|in|IN|O fibrotic|fibrotic|JJ|O areas|area|NNS|O ,|,|,|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O were|be|VBD|O exposed|expose|VBN|O to|to|TO|O tumour|tumour|NN|O necrosis|necrosis|NN|O factor-alpha|factor-alpha|NN|O and|and|CC|O transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta1|beta1|NN|O ;|;|:|O TGF-beta|TGF-beta|NN|GENE suggested|suggest|VBD|O a|a|DT|O trend|trend|NN|O towards|towards|IN|O decreased|decrease|VBN|O synthesis|synthesis|NN|O .|.|.|O 
Patients|patient|NNS|O with|with|IN|O UIP|UIP|NNP|O were|be|VBD|O also|also|RB|O assessed|assess|VBN|O to|to|TO|O determine|determine|VB|O whether|whether|IN|O this|this|DT|O disease|disease|NN|O is|be|VBZ|O associated|associate|VBN|O with|with|IN|O a|a|DT|O naturally|natural|RB|O occurring|occur|VBG|O mutation|mutation|NN|O in|in|IN|O ECSOD|ECSOD|NN|GENE (|(|(|O Arg213Gly|Arg213Gly|NN|O )|)|)|O which|which|WDT|O leads|lead|VBZ|O to|to|TO|O a|a|DT|O loss|loss|NN|O of|of|IN|O tissue|tissue|NN|O binding|binding|NN|O of|of|IN|O ECSOD|ECSOD|NN|GENE .|.|.|O 
No|no|DT|O significant|significant|JJ|O differences|difference|NNS|O could|can|MD|O be|be|VB|O found|find|VBN|O in|in|IN|O the|the|DT|O allele|allele|NN|O or|or|CC|O genotype|genotype|NN|O frequencies|frequency|NNS|O of|of|IN|O this|this|DT|O polymorphism|polymorphism|NN|O between|between|IN|O 63|63|CD|O UIP|UIP|NN|O patients|patient|NNS|O and|and|CC|O 61|61|CD|O control|control|JJ|O subjects|subject|NNS|O .|.|.|O 
CONCLUSION|conclusion|NN|O :|:|:|O Overall|overall|JJ|O ,|,|,|O consistent|consistent|JJ|O with|with|IN|O several|several|JJ|O other|other|JJ|O antioxidant|antioxidant|JJ|O enzymes|enzyme|NNS|O ,|,|,|O ECSOD|ECSOD|NN|GENE is|be|VBZ|O very|very|RB|O low|low|JJ|O in|in|IN|O fibrotic|fibrotic|JJ|O areas|area|NNS|O of|of|IN|O UIP|UIP|NNP|O ,|,|,|O which|which|WDT|O may|may|MD|O further|further|RB|O increase|increase|VB|O the|the|DT|O oxidant|oxidant|JJ|O burden|burden|NN|O in|in|IN|O this|this|DT|O disease|disease|NN|O .|.|.|O 
Tissue|tissue|NN|O inhibitor|inhibitor|NN|O of|of|IN|O metalloproteinase-3|metalloproteinase-3|NN|O is|be|VBZ|O up-regulated|upregulate|VBN|O by|by|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE in|in|FW|O vitro|vitro|FW|O and|and|CC|O expressed|express|VBN|O in|in|IN|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O in|in|FW|O vivo|vivo|FW|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O characterized|characterize|VBN|O by|by|IN|O fibroblast|fibroblast|NN|O expansion|expansion|NN|O and|and|CC|O extracellular|extracellular|JJ|O matrix|matrix|NN|O accumulation|accumulation|NN|O .|.|.|O 
However|however|RB|O ,|,|,|O the|the|DT|O mechanisms|mechanism|NNS|O involved|involve|VBN|O in|in|IN|O matrix|matrix|NN|O remodeling|remodeling|NN|O have|have|VBP|O not|not|RB|O been|be|VBN|O elucidated|elucidate|VBN|O .|.|.|O 
In|in|IN|O this|this|DT|O study|study|NN|O ,|,|,|O the|the|DT|O authors|author|NNS|O aimed|aim|VBN|O to|to|TO|O evaluate|evaluate|VB|O the|the|DT|O expression|expression|NN|O of|of|IN|O the|the|DT|O tissue|tissue|NN|O inhibitors|inhibitor|NNS|O of|of|IN|O matrix|matrix|NN|O metalloproteinases|metalloproteinase|NNS|O (|(|(|O TIMPs|timp|NNS|O )|)|)|O in|in|IN|O human|human|JJ|O fibroblasts|fibroblast|NNS|O and|and|CC|O whole|whole|JJ|O tissues|tissue|NNS|O from|from|IN|O IPF|IPF|NN|O and|and|CC|O normal|normal|JJ|O lungs|lung|NNS|O .|.|.|O 
They|they|PRP|O also|also|RB|O determined|determine|VBD|O the|the|DT|O role|role|NN|O of|of|IN|O mitogen-activated|mitogen-activated|JJ|O protein|protein|NN|O kinase|kinase|NN|O (|(|(|O MAPK|mapk|NN|O )|)|)|O in|in|IN|O TIMP3|TIMP3|NN|O expression|expression|NN|O .|.|.|O 
TIMP1|timp1|NN|O ,|,|,|O TIMP2|TIMP2|NN|O ,|,|,|O and|and|CC|O TIMP3|TIMP3|NN|O were|be|VBD|O highly|high|RB|O expressed|express|VBN|O in|in|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O .|.|.|O 
Transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta1|beta1|NN|O ,|,|,|O a|a|DT|O profibrotic|profibrotic|JJ|O mediator|mediator|NN|O ,|,|,|O induced|induce|VBD|O strong|strong|JJ|O up-regulation|up-regulation|NN|O of|of|IN|O TIMP3|TIMP3|NN|O at|at|IN|O the|the|DT|O mRNA|mRNA|NN|O and|and|CC|O protein|protein|NN|O levels|level|NNS|O .|.|.|O 
The|the|DT|O authors|author|NNS|O examined|examine|VBD|O whether|whether|IN|O the|the|DT|O MAPK|mapk|NN|O pathway|pathway|NN|O was|be|VBD|O involved|involve|VBN|O in|in|IN|O TGF-beta1-induced|tgf-beta1-induced|JJ|O TIMP3|TIMP3|NN|O expression|expression|NN|O .|.|.|O 
TGF-beta1|TGF-beta1|NN|GENE induced|induce|VBD|O the|the|DT|O phosphorylation|phosphorylation|NN|O of|of|IN|O p38|p38|NN|GENE and|and|CC|O extracellular|extracellular|JJ|O signal-regulated|signal-regulated|JJ|O kinase|kinase|NN|O (|(|(|O ERK|erk|NN|GENE )|)|)|O 1/2|1/2|CD|O .|.|.|O 
Biochemical|biochemical|JJ|O blockade|blockade|NN|O of|of|IN|O p38|p38|NN|GENE by|by|IN|O SB203580|SB203580|NN|O ,|,|,|O but|but|CC|O not|not|RB|O of|of|IN|O the|the|DT|O ERK|erk|NN|GENE MAPK|mapk|NN|O pathway|pathway|NN|O ,|,|,|O inhibited|inhibit|VBD|O the|the|DT|O effect|effect|NN|O of|of|IN|O this|this|DT|O factor|factor|NN|O .|.|.|O 
The|the|DT|O effect|effect|NN|O was|be|VBD|O also|also|RB|O blocked|block|VBN|O by|by|IN|O the|the|DT|O tyrosine|tyrosine|NN|O kinase|kinase|NN|O inhibitor|inhibitor|NN|O genistein|genistein|NN|O and|and|CC|O by|by|IN|O antagonizing|antagonize|VBG|O TGF-beta1|TGF-beta1|NN|GENE receptor|receptor|NN|O type|type|NN|O I|i|CD|O (|(|(|O activin-linked|activin-linked|JJ|O kinase|kinase|NN|O [|[|(|O ALK5|ALK5|NN|GENE ]|]|)|O )|)|)|O .|.|.|O 
In|in|IN|O IPF|IPF|NN|O tissues|tissue|NNS|O TIMP3|TIMP3|NN|O gene|gene|NN|O expression|expression|NN|O was|be|VBD|O significantly|significant|RB|O increased|increase|VBN|O and|and|CC|O the|the|DT|O protein|protein|NN|O was|be|VBD|O localized|localized|JJ|O to|to|TO|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O and|and|CC|O extracellular|extracellular|JJ|O matrix|matrix|NN|O .|.|.|O 
Our|our|PRP$|O findings|finding|NNS|O suggest|suggest|VBP|O that|that|IN|O TGF-beta1-induced|tgf-beta1-induced|JJ|O TIMP3|TIMP3|NN|O may|may|MD|O be|be|VB|O an|a|DT|O important|important|JJ|O mediator|mediator|NN|O in|in|IN|O lung|lung|NN|O fibrogenesis|fibrogenesis|NN|O .|.|.|O 
Membrane|membrane|NN|O type-matrix|type-matrix|JJ|O metalloproteinases|metalloproteinase|NNS|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
BACKGROUND|background|NN|O :|:|:|O Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O characterized|characterize|VBN|O by|by|IN|O fibroblast|fibroblast|NN|O expansion|expansion|NN|O and|and|CC|O extracellular|extracellular|JJ|O matrix|matrix|NN|O accumulation|accumulation|NN|O .|.|.|O 
Some|some|DT|O secreted|secrete|VBN|O matrix|matrix|NN|O metalloproteinases|metalloproteinase|NNS|O (|(|(|O MMPs|mmp|NNS|O )|)|)|O as|as|IN|O MMP2|MMP2|NN|GENE are|be|VBP|O highly|high|RB|O upregulated|upregulate|VBN|O in|in|IN|O IPF|IPF|NN|O lungs|lung|NNS|O .|.|.|O 
Membrane-type|membrane-type|JJ|O (|(|(|O MT|mt|NN|O )|)|)|O -|-|:|O MMPs|mmp|NNS|O participate|participate|VBP|O in|in|IN|O the|the|DT|O activation|activation|NN|O of|of|IN|O pro-MMP2|pro-MMP2|NN|O .|.|.|O 
However|however|RB|O ,|,|,|O they|they|PRP|O have|have|VBP|O not|not|RB|O been|be|VBN|O examined|examine|VBN|O in|in|IN|O IPF|IPF|NN|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O Type|type|NN|O I|i|CD|O transmembrane|transmembrane|NN|O MT-MMPs|MT-MMPs|NN|O ,|,|,|O MT1|MT1|NN|GENE ,|,|,|O MT2|MT2|NN|GENE ,|,|,|O MT3|MT3|NN|GENE ,|,|,|O and|and|CC|O MT5-MMP|MT5-MMP|NN|GENE were|be|VBD|O analyzed|analyse|VBN|O by|by|IN|O real-time|real-time|JJ|O PCR|pcr|NN|O and|and|CC|O immunohistochemistry|immunohistochemistry|NN|O in|in|IN|O IPF|IPF|NN|O and|and|CC|O normal|normal|JJ|O lungs|lung|NNS|O .|.|.|O 
MMP-2|MMP-2|NN|GENE was|be|VBD|O also|also|RB|O immunolocalized|immunolocalize|VBN|O and|and|CC|O evaluated|evaluate|VBN|O by|by|IN|O gelatin|gelatin|NN|O zymography|zymography|NN|O in|in|IN|O BAL|bal|NN|O fluids|fluid|NNS|O .|.|.|O 
Additionally|additional|RB|O ,|,|,|O the|the|DT|O MT-MMPs|mt-mmp|NNS|O were|be|VBD|O examined|examine|VBN|O by|by|IN|O real|real|JJ|O time|time|NN|O PCR|pcr|NN|O in|in|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O stimulated|stimulate|VBN|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE and|and|CC|O IFN-gamma|IFN-gamma|NN|GENE .|.|.|O 
RESULTS|result|NNS|O :|:|:|O MT1-MMP|MT1-MMP|NN|O ,|,|,|O was|be|VBD|O the|the|DT|O most|much|RBS|O highly|high|RB|O expressed|express|VBN|O followed|follow|VBN|O by|by|IN|O MT2|MT2|NN|GENE -|-|:|O and|and|CC|O MT5-MMP|MT5-MMP|NN|GENE ,|,|,|O and|and|CC|O by|by|IN|O a|a|DT|O moderate|moderate|JJ|O expression|expression|NN|O of|of|IN|O MT3-MMP|MT3-MMP|NN|O .|.|.|O 
Regarding|regard|VBG|O their|their|PRP$|O localization|localization|NN|O ,|,|,|O MT1|MT1|NN|GENE -|-|:|O and|and|CC|O MT2-MMPs|mt2-mmp|NNS|O were|be|VBD|O found|find|VBN|O in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O ,|,|,|O MT3-MMP|MT3-MMP|NN|O in|in|IN|O fibroblasts|fibroblast|NNS|O from|from|IN|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O and|and|CC|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O and|and|CC|O MT5-MMP|MT5-MMP|NN|GENE in|in|IN|O basal|basal|JJ|O bronchiolar|bronchiolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O and|and|CC|O in|in|IN|O areas|area|NNS|O of|of|IN|O squamous|squamous|JJ|O metaplasia|metaplasia|NN|O .|.|.|O 
MMP2|MMP2|NN|GENE was|be|VBD|O localized|localized|JJ|O in|in|IN|O alveolar|alveolar|JJ|O and|and|CC|O basal|basal|JJ|O bronchiolar|bronchiolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O and|and|CC|O fibroblasts|fibroblast|NNS|O ,|,|,|O and|and|CC|O increased|increase|VBD|O active|active|JJ|O enzyme|enzyme|NN|O was|be|VBD|O observed|observe|VBN|O in|in|IN|O BAL|bal|NN|O fluids|fluid|NNS|O .|.|.|O 
In|in|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O TGF-beta1|TGF-beta1|NN|GENE induced|induce|VBD|O a|a|DT|O strong|strong|JJ|O upregulation|upregulation|NN|O of|of|IN|O MT3-MMP|MT3-MMP|NN|O ,|,|,|O both|both|CC|O at|at|IN|O the|the|DT|O gene|gene|NN|O and|and|CC|O protein|protein|NN|O level|level|NN|O .|.|.|O 
This|this|DT|O effect|effect|NN|O was|be|VBD|O blocked|block|VBN|O by|by|IN|O genistein|genistein|NN|O ,|,|,|O a|a|DT|O protein|protein|NN|O tyrosin|tyrosin|NN|O kinase|kinase|NN|O inhibitor|inhibitor|NN|O and|and|CC|O partially|partial|RB|O repressed|repress|VBN|O by|by|IN|O SB203580|SB203580|NN|O a|a|DT|O p38|p38|NN|GENE MAP|map|NN|O kinase|kinase|NN|O inhibitor|inhibitor|NN|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O MT-MMPs|mt-mmp|NNS|O are|be|VBP|O expressed|express|VBN|O in|in|IN|O IPF|IPF|NN|O ,|,|,|O in|in|IN|O the|the|DT|O same|same|JJ|O cell|cell|NN|O types|type|NNS|O as|as|IN|O MMP2|MMP2|NN|GENE .|.|.|O 
Mostly|most|RB|O by|by|IN|O different|different|JJ|O types|type|NNS|O of|of|IN|O epithelial|epithelial|JJ|O cells|cell|NNS|O a|a|DT|O pivotal|pivotal|JJ|O component|component|NN|O in|in|IN|O the|the|DT|O aberrant|aberrant|JJ|O remodeling|remodeling|NN|O of|of|IN|O the|the|DT|O lung|lung|NN|O microenvironment|microenvironment|NN|O .|.|.|O 
Interestingly|interesting|RB|O MT3-MMP|MT3-MMP|NN|O that|that|WDT|O was|be|VBD|O found|find|VBN|O in|in|IN|O fibroblastic|fibroblastic|JJ|O foci|focus|NNS|O was|be|VBD|O upregulated|upregulate|VBN|O in|in|FW|O vitro|vitro|FW|O by|by|IN|O TGF-beta1|TGF-beta1|NN|GENE a|a|DT|O potent|potent|JJ|O profibrotic|profibrotic|JJ|O mediator|mediator|NN|O .|.|.|O 
Microarray|Microarray|NN|O identifies|identify|VBZ|O ADAM|adam|NNP|O family|family|NN|O members|member|NNS|O as|as|IN|O key|key|JJ|O responders|responder|NNS|O to|to|TO|O TGF-beta1|TGF-beta1|NN|GENE in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O .|.|.|O 
The|the|DT|O molecular|molecular|JJ|O mechanisms|mechanism|NNS|O of|of|IN|O Idiopathic|idiopathic|JJ|O Pulmonary|pulmonary|JJ|O Fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O remain|remain|VBP|O elusive|elusive|JJ|O .|.|.|O 
Transforming|transform|VBG|O Growth|growth|NN|O Factor|factor|NN|O beta|beta|NN|O 1|1|CD|O (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O is|be|VBZ|O a|a|DT|O key|key|JJ|O effector|effector|NN|O cytokine|cytokine|NN|O in|in|IN|O the|the|DT|O development|development|NN|O of|of|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O .|.|.|O 
We|we|PRP|O used|use|VBD|O microarray|microarray|NN|O and|and|CC|O computational|computational|JJ|O biology|biology|NN|O strategies|strategy|NNS|O to|to|TO|O identify|identify|VB|O genes|gene|NNS|O whose|who|WP$|O expression|expression|NN|O is|be|VBZ|O significantly|significant|RB|O altered|alter|VBN|O in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O (|(|(|O A549|A549|NN|O )|)|)|O in|in|IN|O response|response|NN|O to|to|TO|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O IL-4|IL-4|NN|GENE and|and|CC|O IL-13|IL-13|NN|GENE and|and|CC|O Epstein|Epstein|NN|O Barr|Barr|NN|O virus|virus|NN|O .|.|.|O 
A549|A549|NN|O cells|cell|NNS|O were|be|VBD|O exposed|expose|VBN|O to|to|TO|O 10|10|CD|O ng/ml|ng/ml|NN|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O IL-4|IL-4|NN|GENE and|and|CC|O IL-13|IL-13|NN|GENE at|at|IN|O serial|serial|JJ|O time|time|NN|O points|point|NNS|O .|.|.|O 
Total|total|JJ|O RNA|rna|NN|O was|be|VBD|O used|use|VBN|O for|for|IN|O hybridisation|hybridisation|NN|O to|to|TO|O Affymetrix|Affymetrix|NNP|O Human|human|NNP|O Genome|genome|NNP|O U133A|U133A|NN|O microarrays|microarray|NNS|O .|.|.|O 
Each|each|DT|O in|in|FW|O vitro|vitro|FW|O time-point|time-point|NN|O was|be|VBD|O studied|study|VBN|O in|in|IN|O duplicate|duplicate|VB|O and|and|CC|O an|a|DT|O average|average|JJ|O RMA|RMA|NN|O value|value|NN|O computed|compute|VBD|O .|.|.|O 
Expression|expression|NN|O data|datum|NNS|O for|for|IN|O each|each|DT|O time|time|NN|O point|point|NN|O was|be|VBD|O compared|compare|VBN|O to|to|TO|O control|control|VB|O and|and|CC|O a|a|DT|O signal|signal|NN|O log|log|NN|O ratio|ratio|NN|O of|of|IN|O 0.6|0.6|CD|O or|or|CC|O greater|great|JJR|O taken|take|VBN|O to|to|TO|O identify|identify|VB|O significant|significant|JJ|O differential|differential|JJ|O regulation|regulation|NN|O .|.|.|O 
Using|use|VBG|O normalised|normalised|JJ|O RMA|RMA|NN|O values|value|NNS|O and|and|CC|O unsupervised|unsupervised|JJ|O Average|average|JJ|O Linkage|linkage|NN|O Hierarchical|hierarchical|JJ|O Cluster|cluster|NNP|O Analysis|analysis|NN|O ,|,|,|O a|a|DT|O list|list|NN|O of|of|IN|O 312|312|CD|O extracellular|extracellular|JJ|O matrix|matrix|NN|O (|(|(|O ECM|ecm|NN|O )|)|)|O proteins|protein|NNS|O or|or|CC|O modulators|modulator|NNS|O of|of|IN|O matrix|matrix|NN|O turnover|turnover|NN|O was|be|VBD|O curated|curate|VBN|O via|via|IN|O Onto-Compare|Onto-Compare|NNP|O and|and|CC|O Gene-Ontology|Gene-Ontology|NNP|O (|(|(|O GO|go|NNP|O )|)|)|O databases|database|NNS|O for|for|IN|O baited|baited|JJ|O cluster|cluster|NN|O analysis|analysis|NN|O of|of|IN|O ECM|ecm|NN|O associated|associate|VBN|O genes|gene|NNS|O .|.|.|O 
Interrogation|interrogation|NN|O of|of|IN|O the|the|DT|O dataset|dataset|NN|O using|use|VBG|O ontological|ontological|JJ|O classification|classification|NN|O focused|focus|VBD|O cluster|cluster|NN|O analysis|analysis|NN|O revealed|reveal|VBD|O coordinate|coordinate|JJ|O differential|differential|JJ|O expression|expression|NN|O of|of|IN|O a|a|DT|O large|large|JJ|O cohort|cohort|NN|O of|of|IN|O extracellular|extracellular|JJ|O matrix|matrix|NN|O associated|associated|JJ|O genes|gene|NNS|O .|.|.|O 
Of|of|IN|O this|this|DT|O grouping|group|VBG|O members|member|NNS|O of|of|IN|O the|the|DT|O ADAM|adam|NNP|O (|(|(|O A|a|DT|O disintegrin|disintegrin|NN|O and|and|CC|O Metalloproteinase|metalloproteinase|NN|O domain|domain|NN|O containing|contain|VBG|O )|)|)|O family|family|NN|O of|of|IN|O genes|gene|NNS|O were|be|VBD|O differentially|differential|RB|O expressed|express|VBN|O .|.|.|O 
ADAM|adam|NNP|O gene|gene|NN|O expression|expression|NN|O was|be|VBD|O also|also|RB|O identified|identify|VBN|O in|in|IN|O EBV|EBV|NN|O infected|infected|JJ|O A549|A549|NN|O cells|cell|NNS|O as|as|RB|O well|well|RB|O as|as|IN|O IL-13|IL-13|NN|GENE and|and|CC|O IL-4|IL-4|NN|GENE stimulated|stimulate|VBD|O cells|cell|NNS|O .|.|.|O 
We|we|PRP|O probed|probe|VBD|O pathologenomic|pathologenomic|JJ|O activities|activity|NNS|O (|(|(|O activation|activation|NN|O and|and|CC|O functional|functional|JJ|O activity|activity|NN|O )|)|)|O of|of|IN|O ADAM19|ADAM19|NN|O and|and|CC|O ADAMTS9|ADAMTS9|NN|O using|use|VBG|O siRNA|siRNA|NN|O and|and|CC|O collagen|collagen|NN|O assays|assay|NNS|O .|.|.|O 
Knockdown|knockdown|NNP|O of|of|IN|O these|these|DT|O genes|gene|NNS|O resulted|result|VBD|O in|in|IN|O diminished|diminish|VBN|O production|production|NN|O of|of|IN|O collagen|collagen|NN|O in|in|IN|O A549|A549|NN|O cells|cell|NNS|O exposed|expose|VBN|O to|to|TO|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O suggesting|suggest|VBG|O a|a|DT|O potential|potential|JJ|O role|role|NN|O for|for|IN|O these|these|DT|O molecules|molecule|NNS|O in|in|IN|O ECM|ecm|NNP|O accumulation|accumulation|NN|O in|in|IN|O IPF|IPF|NN|O .|.|.|O 
[|[|(|O Quantifying|quantify|VBG|O plasma|plasma|NN|O levels|level|NNS|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O ]|]|)|O .|.|.|O 
OBJECTIVE|objective|NN|O :|:|:|O Transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O ss1|ss1|NN|O (|(|(|O TGF-ss1|TGF-ss1|NN|O )|)|)|O is|be|VBZ|O one|one|CD|O of|of|IN|O the|the|DT|O key|key|JJ|O profibrotic|profibrotic|JJ|O mediators|mediator|NNS|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O .|.|.|O 
The|the|DT|O purpose|purpose|NN|O of|of|IN|O this|this|DT|O study|study|NN|O was|be|VBD|O to|to|TO|O investigate|investigate|VB|O the|the|DT|O prognostic|prognostic|JJ|O value|value|NN|O of|of|IN|O quantifying|quantify|VBG|O TGF-ss1|TGF-ss1|NN|O levels|level|NNS|O in|in|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O .|.|.|O 
PATIENTS|patient|NNS|O AND|and|CC|O METHODS|method|NNS|O :|:|:|O We|we|PRP|O conducted|conduct|VBD|O a|a|DT|O prospective|prospective|JJ|O study|study|NN|O of|of|IN|O 29|29|CD|O IPF|IPF|NN|O patients|patient|NNS|O and|and|CC|O 27|27|CD|O healthy|healthy|JJ|O controls|control|NNS|O .|.|.|O 
Enzyme-linked|enzyme-linked|JJ|O immunosorbent|immunosorbent|JJ|O assays|assay|NNS|O were|be|VBD|O used|use|VBN|O to|to|TO|O quantify|quantify|VB|O TGF-ss1|TGF-ss1|NN|O levels|level|NNS|O .|.|.|O 
RESULTS|result|NNS|O :|:|:|O Mean|mean|NN|O (|(|(|O SD|sd|NN|O )|)|)|O TGF-ss1|TGF-ss1|NN|O levels|level|NNS|O were|be|VBD|O significantly|significant|RB|O higher|high|JJR|O in|in|IN|O the|the|DT|O IPF|IPF|NN|O patients|patient|NNS|O than|than|IN|O in|in|IN|O the|the|DT|O control|control|JJ|O subjects|subject|NNS|O (|(|(|O 11.1|11.1|CD|O [|[|(|O 7.5|7.5|CD|O ]|]|)|O ng/mL|ng/mL|NN|O vs|vs|CC|O 4|4|CD|O [|[|(|O 2.4|2.4|CD|O ]|]|)|O ng/mL|ng/mL|NN|O ;|;|:|O P|p|NN|O <|<|JJR|O .01|.01|CD|O )|)|)|O .|.|.|O 
Weak|weak|JJ|O inverse|inverse|JJ|O correlations|correlation|NNS|O were|be|VBD|O observed|observe|VBN|O between|between|IN|O TGF-ss1|TGF-ss1|NN|O levels|level|NNS|O and|and|CC|O both|both|CC|O forced|force|VBD|O vital|vital|JJ|O capacity|capacity|NN|O and|and|CC|O total|total|JJ|O lung|lung|NN|O capacity|capacity|NN|O .|.|.|O 
Thirteen|thirteen|CD|O IPF|IPF|NN|O patients|patient|NNS|O were|be|VBD|O evaluated|evaluate|VBN|O at|at|IN|O 8|8|CD|O (|(|(|O 1.2|1.2|CD|O )|)|)|O months|month|NNS|O (|(|(|O range|range|NN|O ,|,|,|O 5-9|5-9|CD|O months|month|NNS|O )|)|)|O .|.|.|O 
The|the|DT|O mean|mean|NN|O TGF-ss1|TGF-ss1|NN|O level|level|NN|O was|be|VBD|O 18.2|18.2|CD|O (|(|(|O 15|15|CD|O )|)|)|O ng/mL|ng/mL|NN|O and|and|CC|O there|there|EX|O were|be|VBD|O no|no|DT|O significant|significant|JJ|O differences|difference|NNS|O with|with|IN|O respect|respect|NN|O to|to|TO|O the|the|DT|O initial|initial|JJ|O measurement|measurement|NN|O of|of|IN|O 11.1|11.1|CD|O (|(|(|O 7.5|7.5|CD|O )|)|)|O ng/mL|ng/mL|NN|O .|.|.|O 
No|no|DT|O correlation|correlation|NN|O was|be|VBD|O observed|observe|VBN|O between|between|IN|O changes|change|NNS|O in|in|IN|O respiratory|respiratory|JJ|O function|function|NN|O and|and|CC|O changes|change|NNS|O in|in|IN|O TGF-ss1|TGF-ss1|NN|O levels|level|NNS|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O Although|although|IN|O plasma|plasma|NN|O levels|level|NNS|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE were|be|VBD|O high|high|JJ|O in|in|IN|O the|the|DT|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O ,|,|,|O they|they|PRP|O do|do|VBP|O not|not|RB|O appear|appear|VB|O to|to|TO|O be|be|VB|O a|a|DT|O useful|useful|JJ|O prognostic|prognostic|JJ|O marker|marker|NN|O of|of|IN|O disease|disease|NN|O activity|activity|NN|O or|or|CC|O therapeutic|therapeutic|JJ|O response|response|NN|O .|.|.|O 
Smooth|smooth|JJ|O muscle|muscle|NN|O alpha-actin|alpha-actin|NN|O expression|expression|NN|O and|and|CC|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O by|by|IN|O TGFbeta|TGFbeta|NN|GENE are|be|VBP|O dependent|dependent|JJ|O upon|upon|IN|O MK2|MK2|NN|GENE .|.|.|O 
Fibroblasts|fibroblast|NNS|O play|play|VBP|O a|a|DT|O major|major|JJ|O role|role|NN|O in|in|IN|O processes|process|NNS|O such|such|JJ|O as|as|IN|O wound|wound|NN|O repair|repair|NN|O ,|,|,|O scarring|scarring|NN|O ,|,|,|O and|and|CC|O fibrosis|fibrosis|NN|O .|.|.|O 
Differentiation|differentiation|NN|O into|into|IN|O myofibroblasts|myofibroblast|NNS|O ,|,|,|O characterized|characterize|VBN|O by|by|IN|O upregulation|upregulation|NN|O of|of|IN|O smooth|smooth|JJ|O muscle|muscle|NN|O alpha-actin|alpha-actin|NN|O (|(|(|O smalpha|smalpha|NN|O )|)|)|O in|in|IN|O response|response|NN|O to|to|TO|O profibrotic|profibrotic|JJ|O agents|agent|NNS|O such|such|JJ|O as|as|IN|O TGFbeta|TGFbeta|NN|GENE is|be|VBZ|O believed|believe|VBN|O to|to|TO|O be|be|VB|O an|a|DT|O important|important|JJ|O step|step|NN|O in|in|IN|O fibrosis|fibrosis|NN|O .|.|.|O 
Therefore|therefore|RB|O ,|,|,|O elucidating|elucidate|VBG|O mechanisms|mechanism|NNS|O of|of|IN|O myofibroblast|myofibroblast|NN|O differentiation|differentiation|NN|O might|may|MD|O reveal|reveal|VB|O novel|novel|JJ|O targets|target|NNS|O in|in|IN|O treating|treat|VBG|O diseases|disease|NNS|O such|such|JJ|O as|as|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O .|.|.|O 
MK2|MK2|NN|GENE is|be|VBZ|O a|a|DT|O kinase|kinase|NN|O substrate|substrate|NN|O of|of|IN|O p38|p38|NN|GENE MAP|map|NN|O kinase|kinase|NN|O that|that|WDT|O mediates|mediate|VBZ|O some|some|DT|O effects|effect|NNS|O of|of|IN|O p38|p38|NN|GENE activation|activation|NN|O on|on|IN|O the|the|DT|O actin|actin|NN|O cytoskeleton|cytoskeleton|NN|O .|.|.|O 
Using|use|VBG|O mouse|mouse|NN|O embryonic|embryonic|JJ|O fibroblasts|fibroblast|NNS|O (|(|(|O MEF|MEF|NN|O )|)|)|O from|from|IN|O MK2|MK2|NN|GENE knockout|knockout|NN|O (|(|(|O MK2|MK2|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O )|)|)|O mice|mouse|NNS|O ,|,|,|O we|we|PRP|O demonstrate|demonstrate|VBP|O that|that|IN|O disrupting|disrupt|VBG|O expression|expression|NN|O of|of|IN|O MK2|MK2|NN|GENE expression|expression|NN|O reduces|reduce|VBZ|O filamentous|filamentous|JJ|O actin|actin|NN|O and|and|CC|O stress|stress|NN|O fibers|fiber|NNS|O .|.|.|O 
It|it|PRP|O also|also|RB|O causes|cause|VBZ|O MK2|MK2|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O MEF|MEF|NN|O to|to|TO|O express|express|VB|O less|little|JJR|O smalpha|smalpha|NN|O than|than|IN|O their|their|PRP$|O corresponding|corresponding|JJ|O wild-type|wild-type|JJ|O (|(|(|O WT|wt|JJ|O )|)|)|O MEF|MEF|NN|O at|at|IN|O baseline|baseline|NN|O and|and|CC|O in|in|IN|O response|response|NN|O to|to|TO|O TGFbeta|TGFbeta|NN|GENE .|.|.|O 
Furthermore|furthermore|RB|O ,|,|,|O TGFbeta|TGFbeta|NN|GENE causes|cause|VBZ|O downregulation|downregulation|NN|O of|of|IN|O smalpha|smalpha|NN|O in|in|IN|O MK2|MK2|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O MEF|MEF|NN|O ,|,|,|O instead|instead|RB|O of|of|IN|O upregulation|upregulation|NN|O observed|observe|VBN|O in|in|IN|O WT|wt|NNP|O MEF|MEF|NNP|O .|.|.|O 
Expression|expression|NN|O of|of|IN|O other|other|JJ|O fibroblast|fibroblast|NN|O markers|marker|NNS|O ,|,|,|O such|such|JJ|O as|as|IN|O collagen|collagen|NN|O ,|,|,|O is|be|VBZ|O not|not|RB|O altered|alter|VBN|O in|in|IN|O MK2|MK2|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O MEF|MEF|NN|O .|.|.|O 
Our|our|PRP$|O results|result|NNS|O further|further|RB|O suggest|suggest|VBP|O that|that|IN|O downregulation|downregulation|NN|O of|of|IN|O smalpha|smalpha|NN|O in|in|IN|O MK2|MK2|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O MEF|MEF|NN|O is|be|VBZ|O not|not|RB|O due|due|JJ|O to|to|TO|O lack|lack|NN|O of|of|IN|O activation|activation|NN|O of|of|IN|O serum|serum|NN|O responsive|responsive|JJ|O promoter|promoter|NN|O elements|element|NNS|O ,|,|,|O but|but|CC|O probably|probable|RB|O due|due|JJ|O to|to|TO|O reduced|reduce|VBN|O smalpha|smalpha|NN|O message|message|NN|O stability|stability|NN|O in|in|IN|O these|these|DT|O cells|cell|NNS|O .|.|.|O 
These|these|DT|O results|result|NNS|O indicate|indicate|VBP|O that|that|IN|O MK2|MK2|NN|GENE plays|play|VBZ|O a|a|DT|O key|key|JJ|O role|role|NN|O in|in|IN|O regulation|regulation|NN|O of|of|IN|O smalpha|smalpha|NN|O expression|expression|NN|O ,|,|,|O and|and|CC|O that|that|IN|O targeting|target|VBG|O MK2|MK2|NN|GENE might|may|MD|O present|present|VB|O a|a|DT|O therapeutic|therapeutic|JJ|O approach|approach|NN|O in|in|IN|O managing|managing|NN|O conditions|condition|NNS|O such|such|JJ|O as|as|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Caveolin-1|Caveolin-1|NN|GENE :|:|:|O a|a|DT|O critical|critical|JJ|O regulator|regulator|NN|O of|of|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O progressive|progressive|JJ|O chronic|chronic|JJ|O disorder|disorder|NN|O characterized|characterize|VBN|O by|by|IN|O activation|activation|NN|O of|of|IN|O fibroblasts|fibroblast|NNS|O and|and|CC|O overproduction|overproduction|NN|O of|of|IN|O extracellular|extracellular|JJ|O matrix|matrix|NN|O (|(|(|O ECM|ecm|NN|O )|)|)|O .|.|.|O 
Caveolin-1|Caveolin-1|NN|GENE (|(|(|O cav-1|cav-1|NN|O )|)|)|O ,|,|,|O a|a|DT|O principal|principal|JJ|O component|component|NN|O of|of|IN|O caveolae|caveolae|FW|O ,|,|,|O has|have|VBZ|O been|be|VBN|O implicated|implicate|VBN|O in|in|IN|O the|the|DT|O regulation|regulation|NN|O of|of|IN|O numerous|numerous|JJ|O signaling|signaling|NN|O pathways|pathway|NNS|O and|and|CC|O biological|biological|JJ|O processes|process|NNS|O .|.|.|O 
We|we|PRP|O observed|observe|VBD|O marked|marked|JJ|O reduction|reduction|NN|O of|of|IN|O cav-1|cav-1|NN|O expression|expression|NN|O in|in|IN|O lung|lung|NN|O tissues|tissue|NNS|O and|and|CC|O in|in|IN|O primary|primary|JJ|O pulmonary|pulmonary|JJ|O fibroblasts|fibroblast|NNS|O from|from|IN|O IPF|IPF|NN|O patients|patient|NNS|O compared|compare|VBN|O with|with|IN|O controls|control|NNS|O .|.|.|O 
We|we|PRP|O also|also|RB|O demonstrated|demonstrate|VBD|O that|that|IN|O cav-1|cav-1|NN|O markedly|marked|RB|O ameliorated|ameliorate|VBD|O bleomycin|bleomycin|NN|O (|(|(|O BLM|Blm|NN|O )|)|)|O -|-|:|O induced|induce|VBN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O ,|,|,|O as|as|IN|O indicated|indicate|VBN|O by|by|IN|O histological|histological|JJ|O analysis|analysis|NN|O ,|,|,|O hydroxyproline|hydroxyproline|NN|O content|content|NN|O ,|,|,|O and|and|CC|O immunoblot|immunoblot|NN|O analysis|analysis|NN|O .|.|.|O 
Additionally|additional|RB|O ,|,|,|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O ,|,|,|O the|the|DT|O well-known|well-known|JJ|O profibrotic|profibrotic|JJ|O cytokine|cytokine|NN|O ,|,|,|O decreased|decrease|VBD|O cav-1|cav-1|NN|O expression|expression|NN|O in|in|IN|O human|human|JJ|O pulmonary|pulmonary|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
cav-1|cav-1|NN|O was|be|VBD|O able|able|JJ|O to|to|TO|O suppress|suppress|VB|O TGF-beta1-induced|tgf-beta1-induced|JJ|O ECM|ecm|NN|O production|production|NN|O in|in|IN|O cultured|culture|VBN|O fibroblasts|fibroblast|NNS|O through|through|IN|O the|the|DT|O regulation|regulation|NN|O of|of|IN|O the|the|DT|O c-Jun|c-jun|NN|GENE N-terminal|N-terminal|JJ|O kinase|kinase|NN|O (|(|(|O JNK|jnk|NN|GENE )|)|)|O pathway|pathway|NN|O .|.|.|O 
Interestingly|interesting|RB|O ,|,|,|O highly|high|RB|O activated|activate|VBN|O JNK|jnk|NN|GENE was|be|VBD|O detected|detect|VBN|O in|in|IN|O IPF|IPF|NN|O -|-|:|O and|and|CC|O BLM-instilled|blm-instilled|JJ|O lung|lung|NN|O tissue|tissue|NN|O samples|sample|NNS|O ,|,|,|O which|which|WDT|O was|be|VBD|O dramatically|dramatic|RB|O suppressed|suppress|VBN|O by|by|IN|O ad-cav-1|ad-cav-1|NN|O infection|infection|NN|O .|.|.|O 
Moreover|moreover|RB|O ,|,|,|O JNK1-null|jnk1-null|JJ|O fibroblasts|fibroblast|NNS|O showed|show|VBD|O reduced|reduce|VBN|O smad|SMAD|NN|O signaling|signaling|NN|O cascades|cascade|NNS|O ,|,|,|O mimicking|mimic|VBG|O the|the|DT|O effects|effect|NNS|O of|of|IN|O cav-1|cav-1|NN|O .|.|.|O 
This|this|DT|O study|study|NN|O indicates|indicate|VBZ|O a|a|DT|O pivotal|pivotal|JJ|O role|role|NN|O for|for|IN|O cav-1|cav-1|NN|O in|in|IN|O ECM|ecm|NN|O regulation|regulation|NN|O and|and|CC|O suggests|suggest|VBZ|O a|a|DT|O novel|novel|JJ|O therapeutic|therapeutic|JJ|O target|target|NN|O for|for|IN|O patients|patient|NNS|O with|with|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Overproduction|overproduction|NN|O of|of|IN|O collagen|collagen|NN|O and|and|CC|O diminished|diminish|VBD|O SOCS1|SOCS1|NN|GENE expression|expression|NN|O are|be|VBP|O causally|causal|RB|O linked|link|VBN|O in|in|IN|O fibroblasts|fibroblast|NNS|O from|from|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O chronic|chronic|JJ|O ,|,|,|O progressive|progressive|JJ|O ,|,|,|O and|and|CC|O often|often|RB|O fatal|fatal|JJ|O pulmonary|pulmonary|JJ|O disorder|disorder|NN|O ,|,|,|O and|and|CC|O its|its|PRP$|O pathology|pathology|NN|O is|be|VBZ|O characterized|characterize|VBN|O by|by|IN|O parenchymal|parenchymal|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
To|to|TO|O investigate|investigate|VB|O the|the|DT|O characteristics|characteristic|NNS|O of|of|IN|O fibroblasts|fibroblast|NNS|O in|in|IN|O IPF|IPF|NN|O ,|,|,|O we|we|PRP|O obtained|obtain|VBD|O eight|eight|CD|O fibroblast|fibroblast|NN|O cell|cell|NN|O lines|line|NNS|O from|from|IN|O lungs|lung|NNS|O with|with|IN|O IPF|IPF|NN|O and|and|CC|O eight|eight|CD|O lines|line|NNS|O from|from|IN|O normal|normal|JJ|O lungs|lung|NNS|O .|.|.|O 
We|we|PRP|O found|find|VBD|O that|that|IN|O the|the|DT|O fibroblasts|fibroblast|NNS|O from|from|IN|O IPF|IPF|NN|O spontaneously|spontaneous|RB|O produced|produce|VBD|O higher|high|JJR|O amounts|amount|NNS|O of|of|IN|O type|type|NN|O I|i|CD|O collagen|collagen|NN|O and|and|CC|O had|have|VBD|O lower|low|JJR|O expression|expression|NN|O levels|level|NNS|O of|of|IN|O SOCS1|SOCS1|NN|GENE than|than|IN|O fibroblasts|fibroblast|NNS|O from|from|IN|O normal|normal|JJ|O lung|lung|NN|O .|.|.|O 
By|by|IN|O using|use|VBG|O mouse|mouse|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O we|we|PRP|O demonstrated|demonstrate|VBD|O the|the|DT|O causal|causal|JJ|O relationship|relationship|NN|O between|between|IN|O them|they|PRP|O :|:|:|O the|the|DT|O deficiency|deficiency|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE in|in|IN|O fibroblasts|fibroblast|NNS|O resulted|result|VBD|O in|in|IN|O increased|increase|VBN|O collagen|collagen|NN|O production|production|NN|O ,|,|,|O whereas|whereas|IN|O overexpression|overexpression|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE suppressed|suppress|VBD|O collagen|collagen|NN|O production|production|NN|O .|.|.|O 
IFN-gamma|IFN-gamma|NN|GENE suppressed|suppress|VBD|O spontaneous|spontaneous|JJ|O collagen|collagen|NN|O production|production|NN|O even|even|RB|O in|in|IN|O SOCS1-deficient|socs1-deficient|JJ|O fibroblasts|fibroblast|NNS|O ,|,|,|O indicating|indicate|VBG|O that|that|IN|O IFN-gamma|IFN-gamma|NN|GENE inhibition|inhibition|NN|O is|be|VBZ|O SOCS1-independent|socs1-independent|JJ|O .|.|.|O 
In|in|IN|O contrast|contrast|NN|O ,|,|,|O IFN-gamma|IFN-gamma|NN|GENE suppressed|suppress|VBD|O the|the|DT|O increase|increase|NN|O of|of|IN|O collagen|collagen|NN|O production|production|NN|O induced|induce|VBN|O by|by|IN|O IL-4|IL-4|NN|GENE in|in|IN|O wild|wild|JJ|O type|type|NN|O fibroblasts|fibroblast|NNS|O but|but|CC|O not|not|RB|O SOCS1-deficient|socs1-deficient|JJ|O fibroblasts|fibroblast|NNS|O ,|,|,|O suggesting|suggest|VBG|O IFN-gamma|IFN-gamma|NN|GENE acted|act|VBD|O exclusively|exclusive|RB|O via|via|IN|O SOCS1|SOCS1|NN|GENE in|in|IN|O this|this|DT|O case|case|NN|O .|.|.|O 
Following|follow|VBG|O IFN-gamma|IFN-gamma|NN|GENE stimulation|stimulation|NN|O ,|,|,|O the|the|DT|O amount|amount|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE mRNA|mRNA|NN|O expressed|express|VBN|O by|by|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O was|be|VBD|O comparable|comparable|JJ|O to|to|TO|O that|that|DT|O of|of|IN|O normal|normal|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
Thus|thus|RB|O ,|,|,|O the|the|DT|O extent|extent|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE increase|increase|NN|O after|after|IN|O stimulation|stimulation|NN|O by|by|IN|O IFN-gamma|IFN-gamma|NN|GENE was|be|VBD|O significantly|significant|RB|O higher|high|JJR|O in|in|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O .|.|.|O 
The|the|DT|O extent|extent|NN|O to|to|TO|O which|which|WDT|O IFN-gamma|IFN-gamma|NN|GENE inhibited|inhibit|VBD|O collagen|collagen|NN|O production|production|NN|O was|be|VBD|O also|also|RB|O larger|large|JJR|O in|in|IN|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O than|than|IN|O in|in|IN|O normal|normal|JJ|O fibroblasts|fibroblast|NNS|O .|.|.|O 
These|these|DT|O results|result|NNS|O suggest|suggest|VBP|O that|that|IN|O the|the|DT|O exaggerated|exaggerated|JJ|O production|production|NN|O of|of|IN|O collagen|collagen|NN|O observed|observe|VBN|O in|in|IN|O fibroblasts|fibroblast|NNS|O from|from|IN|O IPF|IPF|NN|O is|be|VBZ|O causally|causal|RB|O related|related|JJ|O to|to|TO|O the|the|DT|O diminished|diminish|VBN|O expression|expression|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE ,|,|,|O and|and|CC|O IPF|IPF|NN|O fibroblasts|fibroblast|NNS|O are|be|VBP|O more|much|RBR|O susceptible|susceptible|JJ|O to|to|TO|O IFN-gamma|IFN-gamma|NN|GENE because|because|IN|O of|of|IN|O decreased|decrease|VBN|O expression|expression|NN|O of|of|IN|O SOCS1|SOCS1|NN|GENE .|.|.|O 
Control|control|NN|O of|of|IN|O virus|virus|NN|O reactivation|reactivation|NN|O arrests|arrest|NNS|O pulmonary|pulmonary|JJ|O herpesvirus-induced|herpesvirus-induced|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O IFN-gamma|IFN-gamma|NN|GENE receptor-deficient|receptor-deficient|JJ|O mice|mouse|NNS|O .|.|.|O 
RATIONALE|rationale|NN|O :|:|:|O Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O chronic|chronic|JJ|O progressive|progressive|JJ|O fibrotic|fibrotic|JJ|O lung|lung|NN|O disorder|disorder|NN|O of|of|IN|O unknown|unknown|JJ|O cause|cause|NN|O .|.|.|O 
Several|several|JJ|O studies|study|NNS|O suggest|suggest|VBP|O an|a|DT|O association|association|NN|O between|between|IN|O Epstein-Barr|epstein-barr|JJ|O virus|virus|NN|O pulmonary|pulmonary|JJ|O infection|infection|NN|O and|and|CC|O the|the|DT|O development|development|NN|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
OBJECTIVES|objective|NNS|O :|:|:|O To|to|TO|O determine|determine|VB|O whether|whether|IN|O reduction|reduction|NN|O of|of|IN|O gamma-herpesvirus|gamma-herpesvirus|NN|O reactivation|reactivation|NN|O from|from|IN|O latency|latency|NN|O would|will|MD|O alter|alter|VB|O progressive|progressive|JJ|O lung|lung|NN|O fibrogenesis|fibrogenesis|NN|O in|in|IN|O an|a|DT|O animal|animal|NN|O model|model|NN|O of|of|IN|O virus-induced|virus-induced|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O IFN-gamma|IFN-gamma|NN|GENE receptor-deficient|receptor-deficient|JJ|O (|(|(|O IFN-gammaR|IFN-gammaR|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O )|)|)|O mice|mouse|NNS|O infected|infected|JJ|O intranasally|intranasal|RB|O with|with|IN|O murine|murine|JJ|O gamma-herpesvirus|gamma-herpesvirus|NN|O 68|68|CD|O (|(|(|O MHV68|MHV68|NN|O )|)|)|O develop|develop|VBP|O lung|lung|NN|O fibrosis|fibrosis|NN|O that|that|WDT|O progresses|progress|VBZ|O for|for|IN|O up|up|RB|O to|to|TO|O at|at|IN|O least|little|JJS|O 180|180|CD|O days|day|NNS|O after|after|IN|O initial|initial|JJ|O infection|infection|NN|O .|.|.|O 
Viral|viral|JJ|O replication|replication|NN|O during|during|IN|O the|the|DT|O chronic|chronic|JJ|O phase|phase|NN|O of|of|IN|O infection|infection|NN|O was|be|VBD|O controlled|control|VBN|O by|by|IN|O two|two|CD|O methods|method|NNS|O :|:|:|O the|the|DT|O administration|administration|NN|O of|of|IN|O cidofovir|cidofovir|NN|O ,|,|,|O an|a|DT|O antiviral|antiviral|JJ|O drug|drug|NN|O effective|effective|JJ|O at|at|IN|O clearing|clear|VBG|O lytic|lytic|JJ|O but|but|CC|O not|not|RB|O latent|latent|JJ|O virus|virus|NN|O ,|,|,|O and|and|CC|O by|by|IN|O using|use|VBG|O a|a|DT|O mutant|mutant|JJ|O gamma-herpesvirus|gamma-herpesvirus|NN|O defective|defective|JJ|O in|in|IN|O virus|virus|NN|O reactivation|reactivation|NN|O from|from|IN|O latency|latency|NN|O .|.|.|O 
MEASUREMENTS|measurement|NNS|O AND|and|CC|O MAIN|main|NNS|O RESULTS|result|NNS|O :|:|:|O Ten|ten|CD|O percent|percent|NN|O of|of|IN|O the|the|DT|O asymptomatic|asymptomatic|JJ|O MHV68-infected|mhv68-infected|JJ|O animals|animal|NNS|O that|that|WDT|O received|receive|VBD|O antiviral|antiviral|JJ|O treatment|treatment|NN|O beginning|beginning|NN|O on|on|IN|O Day|day|NN|O 45|45|CD|O postinfection|postinfection|NN|O had|have|VBD|O severe|severe|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O compared|compare|VBN|O with|with|IN|O 40|40|CD|O %|%|NN|O of|of|IN|O the|the|DT|O control|control|NN|O saline-treated|saline-treated|JJ|O animals|animal|NNS|O .|.|.|O 
Absence|absence|NN|O of|of|IN|O severe|severe|JJ|O fibrosis|fibrosis|NN|O was|be|VBD|O also|also|RB|O observed|observe|VBN|O in|in|IN|O IFN-gammaR|IFN-gammaR|NN|GENE (|(|(|O -|-|:|O /|/|:|O -|-|:|O )|)|)|O mice|mouse|NNS|O infected|infect|VBN|O with|with|IN|O the|the|DT|O defective|defective|JJ|O reactivation|reactivation|NN|O mutant|mutant|JJ|O MHV68|MHV68|NN|O v-cyclin|v-cyclin|NN|O stop|stop|NN|O .|.|.|O 
Decreased|decrease|VBN|O fibrosis|fibrosis|NN|O was|be|VBD|O associated|associate|VBN|O with|with|IN|O lower|low|JJR|O levels|level|NNS|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta|beta|NN|GENE ,|,|,|O vascular|vascular|NN|GENE endothelial|endothelial|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE ,|,|,|O and|and|CC|O markers|marker|NNS|O of|of|IN|O macrophage|macrophage|NN|O alternative|alternative|NN|O activation|activation|NN|O .|.|.|O 
When|when|WRB|O antiviral|antiviral|JJ|O treatment|treatment|NN|O was|be|VBD|O administered|administer|VBN|O on|on|IN|O Day|day|NN|O 60|60|CD|O in|in|IN|O symptomatic|symptomatic|JJ|O animals|animal|NNS|O ,|,|,|O survival|survival|NN|O improved|improve|VBN|O from|from|IN|O 20|20|CD|O to|to|TO|O 80|80|CD|O %|%|NN|O compared|compare|VBN|O with|with|IN|O untreated|untreated|JJ|O symptomatic|symptomatic|JJ|O animals|animal|NNS|O ,|,|,|O but|but|CC|O lung|lung|NN|O fibrosis|fibrosis|NN|O persisted|persist|VBD|O in|in|IN|O 60|60|CD|O %|%|NN|O of|of|IN|O the|the|DT|O mice|mouse|NNS|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O MHV68-induced|mhv68-induced|JJ|O fibrosis|fibrosis|NN|O is|be|VBZ|O a|a|DT|O result|result|NN|O of|of|IN|O viral|viral|JJ|O lytic|lytic|JJ|O replication|replication|NN|O during|during|IN|O chronic|chronic|JJ|O lung|lung|NN|O herpesvirus|herpesvirus|NN|O infection|infection|NN|O in|in|IN|O mice|mouse|NNS|O .|.|.|O 
We|we|PRP|O speculate|speculate|VBP|O that|that|IN|O antiviral|antiviral|JJ|O therapy|therapy|NN|O might|may|MD|O help|help|VB|O to|to|TO|O control|control|VB|O lung|lung|NN|O fibrosis|fibrosis|NN|O in|in|IN|O humans|human|NNS|O with|with|IN|O IPF|IPF|NN|O and|and|CC|O associated|associate|VBN|O herpesvirus|herpesvirus|NN|O infection|infection|NN|O .|.|.|O 
Endothelin-1|Endothelin-1|NN|GENE induces|induce|VBZ|O alveolar|alveolar|JJ|O epithelial-mesenchymal|epithelial-mesenchymal|JJ|O transition|transition|NN|O through|through|IN|O endothelin|endothelin|NN|O type|type|NN|O A|a|NN|O receptor-mediated|receptor-mediated|JJ|O production|production|NN|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE .|.|.|O 
Endothelin-1|Endothelin-1|NN|GENE (|(|(|O ET-1|ET-1|NN|GENE )|)|)|O is|be|VBZ|O implicated|implicate|VBN|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O but|but|CC|O the|the|DT|O cellular|cellular|JJ|O mechanisms|mechanism|NNS|O underlying|underlie|VBG|O the|the|DT|O role|role|NN|O it|it|PRP|O plays|play|VBZ|O in|in|IN|O this|this|DT|O disease|disease|NN|O are|be|VBP|O not|not|RB|O well|well|RB|O characterized|characterize|VBN|O .|.|.|O 
Epithelial-mesenchymal|epithelial-mesenchymal|JJ|O transition|transition|NN|O (|(|(|O EMT|emt|NN|GENE )|)|)|O ,|,|,|O which|which|WDT|O was|be|VBD|O recently|recent|RB|O demonstrated|demonstrate|VBN|O in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O (|(|(|O AEC|aec|NNS|O )|)|)|O ,|,|,|O may|may|MD|O play|play|VB|O an|a|DT|O important|important|JJ|O role|role|NN|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O IPF|IPF|NN|O and|and|CC|O other|other|JJ|O forms|form|NNS|O of|of|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Whether|whether|IN|O ET-1|ET-1|NN|GENE contributes|contribute|VBZ|O to|to|TO|O the|the|DT|O induction|induction|NN|O of|of|IN|O EMT|emt|NNP|GENE in|in|IN|O AEC|aec|NNP|O is|be|VBZ|O unknown|unknown|JJ|O .|.|.|O 
The|the|DT|O aims|aim|NNS|O of|of|IN|O this|this|DT|O study|study|NN|O were|be|VBD|O to|to|TO|O evaluate|evaluate|VB|O AEC|aec|NN|O production|production|NN|O of|of|IN|O ET-1|ET-1|NN|GENE and|and|CC|O to|to|TO|O determine|determine|VB|O if|if|IN|O ET-1|ET-1|NN|GENE induces|induce|VBZ|O EMT|emt|NNP|GENE in|in|IN|O AEC|aec|NNP|O .|.|.|O 
We|we|PRP|O demonstrate|demonstrate|VBP|O that|that|IN|O ET-1|ET-1|NN|GENE is|be|VBZ|O produced|produce|VBN|O at|at|IN|O physiologically|physiological|RB|O relevant|relevant|JJ|O levels|level|NNS|O by|by|IN|O primary|primary|JJ|O AEC|aec|NN|O and|and|CC|O is|be|VBZ|O secreted|secrete|VBN|O preferentially|preferential|RB|O toward|toward|IN|O the|the|DT|O basolateral|basolateral|JJ|O surface|surface|NN|O .|.|.|O 
We|we|PRP|O also|also|RB|O demonstrate|demonstrate|VBP|O that|that|IN|O AEC|aec|NNS|O express|express|VBP|O high|high|JJ|O levels|level|NNS|O of|of|IN|O endothelin|endothelin|NNS|GENE type|type|NNS|GENE A|a|NNS|GENE receptors|receptor|NNS|GENE (|(|(|O ET-A|ET-A|NN|GENE )|)|)|O and|and|CC|O ,|,|,|O to|to|TO|O a|a|DT|O lesser|less|JJR|O extent,|extent,|NNS|GENE type|type|NNS|GENE B|B|NNS|GENE receptors|receptors|NNS|GENE (|(|(|O ET-B|ET-B|NN|GENE )|)|)|O ,|,|,|O suggesting|suggest|VBG|O autocrine|autocrine|JJ|O or|or|CC|O paracrine|paracrine|JJ|O function|function|NN|O for|for|IN|O alveolar|alveolar|JJ|O ET-1|ET-1|NN|GENE .|.|.|O 
In|in|IN|O addition|addition|NN|O ,|,|,|O ET-1|ET-1|NN|GENE induces|induce|VBZ|O EMT|emt|NN|GENE through|through|IN|O ET-A|ET-A|NN|GENE activation|activation|NN|O .|.|.|O 
Furthermore|furthermore|RB|O ,|,|,|O TGF-beta1|TGF-beta1|NN|GENE synthesis|synthesis|NN|O is|be|VBZ|O increased|increase|VBN|O by|by|IN|O ET-1|ET-1|NN|GENE ,|,|,|O ET-1|ET-1|NN|GENE induces|induce|VBZ|O Smad3|Smad3|NN|GENE phosphorylation|phosphorylation|NN|O ,|,|,|O and|and|CC|O ET-1-induced|et-1-induced|JJ|O EMT|emt|NN|GENE is|be|VBZ|O attenuated|attenuate|VBN|O by|by|IN|O a|a|DT|O TGF-beta1-neutralizing|tgf-beta1-neutralizing|JJ|O antibody|antibody|NN|O .|.|.|O 
Thus|thus|RB|O ,|,|,|O ET-1|ET-1|NN|GENE is|be|VBZ|O an|a|DT|O important|important|JJ|O mediator|mediator|NN|O of|of|IN|O EMT|emt|NNP|GENE in|in|IN|O AEC|aec|NNP|O ,|,|,|O acting|act|VBG|O through|through|IN|O ET-A-mediated|et-a-mediated|JJ|O TGF-beta1|TGF-beta1|NN|GENE production|production|NN|O .|.|.|O 
These|these|DT|O findings|finding|NNS|O increase|increase|VBP|O our|our|PRP$|O basic|basic|JJ|O understanding|understanding|NN|O of|of|IN|O the|the|DT|O role|role|NN|O of|of|IN|O ET-1|ET-1|NN|GENE in|in|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O and|and|CC|O suggest|suggest|VBP|O potential|potential|JJ|O roles|role|NNS|O for|for|IN|O AEC-derived|aec-derived|JJ|O ET-1|ET-1|NN|GENE in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O other|other|JJ|O alveolar|alveolar|JJ|O epithelial-mediated|epithelial-mediated|JJ|O lung|lung|NN|O diseases|disease|NNS|O .|.|.|O 
Effects|effect|NNS|O of|of|IN|O antifibrotic|antifibrotic|JJ|O agents|agent|NNS|O on|on|IN|O TGF-beta1|TGF-beta1|NN|GENE ,|,|,|O CTGF|Ctgf|NN|GENE and|and|CC|O IFN-gamma|IFN-gamma|NN|GENE expression|expression|NN|O in|in|IN|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O deadly|deadly|JJ|O disease|disease|NN|O ,|,|,|O largely|large|RB|O unresponsive|unresponsive|JJ|O to|to|TO|O treatment|treatment|NN|O with|with|IN|O corticosteroids|corticosteroid|NNS|O and|and|CC|O immunosuppressives|immunosuppressive|NNS|O .|.|.|O 
The|the|DT|O aim|aim|NN|O of|of|IN|O this|this|DT|O randomized|randomize|VBN|O ,|,|,|O prospective|prospective|JJ|O ,|,|,|O open-label|open-label|JJ|O study|study|NN|O was|be|VBD|O to|to|TO|O characterize|characterize|VB|O the|the|DT|O molecular|molecular|JJ|O effects|effect|NNS|O of|of|IN|O IFN-gamma-1b|IFN-gamma-1b|NN|O and|and|CC|O colchicine|colchicine|NN|O ,|,|,|O on|on|IN|O biomarkers|biomarker|NNS|O expression|expression|NN|O associated|associate|VBN|O with|with|IN|O fibrosis|fibrosis|NN|O (|(|(|O TGF-beta|TGF-beta|NN|GENE ,|,|,|O CTGF|Ctgf|NN|GENE )|)|)|O and|and|CC|O immunomodulatory/antimicrobial|immunomodulatory/antimicrobial|JJ|O activity|activity|NN|O (|(|(|O IFN-gamma|IFN-gamma|NN|GENE )|)|)|O ,|,|,|O in|in|IN|O the|the|DT|O lungs|lung|NNS|O of|of|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O .|.|.|O 
Fourteen|fourteen|CD|O (|(|(|O 14|14|CD|O )|)|)|O patients|patient|NNS|O with|with|IN|O an|a|DT|O established|established|JJ|O diagnosis|diagnosis|NN|O of|of|IN|O IPF|IPF|NN|O received|receive|VBD|O either|either|CC|O 200|200|CD|O microg|microg|NN|O of|of|IN|O IFN-gamma-1b|IFN-gamma-1b|NN|O subcutaneously|subcutaneous|RB|O three|three|CD|O times|time|NNS|O per|per|IN|O week|week|NN|O ,|,|,|O or|or|CC|O 1|1|CD|O mg|mg|NN|O of|of|IN|O oral|oral|JJ|O colchicine|colchicine|NN|O per|per|IN|O day|day|NN|O ,|,|,|O for|for|IN|O 24|24|CD|O months|month|NNS|O .|.|.|O 
Using|use|VBG|O RT-PCR|rt-pcr|NN|O assay|assay|NN|O ,|,|,|O we|we|PRP|O evaluated|evaluate|VBD|O the|the|DT|O transcription|transcription|NN|O levels|level|NNS|O of|of|IN|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O ,|,|,|O connective-tissue|connective-tissue|JJ|O growth|growth|NN|O factor|factor|NN|O (|(|(|O CTGF|Ctgf|NN|GENE )|)|)|O ,|,|,|O and|and|CC|O interferon-gamma|interferon-gamma|NN|O (|(|(|O IFN-gamma|IFN-gamma|NN|GENE )|)|)|O genes|gene|NNS|O in|in|IN|O lung|lung|NN|O tissue|tissue|NN|O before|before|IN|O and|and|CC|O after|after|IN|O treatment|treatment|NN|O with|with|IN|O IFN-gamma-1b|IFN-gamma-1b|NN|O or|or|CC|O colchicine|colchicine|NN|O .|.|.|O 
Marked|marked|JJ|O mRNA|mRNA|NN|O expression|expression|NN|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE and|and|CC|O CTGF|Ctgf|NN|GENE ,|,|,|O but|but|CC|O complete|complete|JJ|O lack|lack|NN|O of|of|IN|O interferon-gamma|interferon-gamma|NN|O was|be|VBD|O detected|detect|VBN|O in|in|IN|O fibrotic|fibrotic|JJ|O lung|lung|NN|O tissue|tissue|NN|O at|at|IN|O entry|entry|NN|O .|.|.|O 
After|after|IN|O treatment|treatment|NN|O ,|,|,|O both|both|DT|O groups|group|NNS|O exhibited|exhibit|VBD|O increased|increase|VBN|O expression|expression|NN|O of|of|IN|O IFN-gamma|IFN-gamma|NN|GENE gene|gene|NN|O at|at|IN|O 6|6|CD|O months|month|NNS|O that|that|WDT|O was|be|VBD|O sustained|sustain|VBN|O at|at|IN|O 24|24|CD|O months|month|NNS|O .|.|.|O 
The|the|DT|O expression|expression|NN|O of|of|IN|O CTGF|Ctgf|NN|GENE and|and|CC|O TGF-beta1|TGF-beta1|NN|GENE remained|remain|VBD|O almost|almost|RB|O stable|stable|JJ|O before|before|IN|O and|and|CC|O after|after|IN|O treatment|treatment|NN|O ,|,|,|O in|in|IN|O the|the|DT|O IFN-gamma-1b|ifn-gamma-1b|JJ|O group|group|NN|O ,|,|,|O while|while|IN|O TGF-beta1|TGF-beta1|NN|GENE was|be|VBD|O statistically|statistical|RB|O decreased|decrease|VBN|O after|after|IN|O therapy|therapy|NN|O ,|,|,|O in|in|IN|O the|the|DT|O colchicine|colchicine|NN|O group|group|NN|O (|(|(|O p|p|NN|O =|=|JJ|O 0.0002|0.0002|CD|O )|)|)|O .|.|.|O 
Significant|significant|JJ|O difference|difference|NN|O in|in|IN|O DLCO|DLCO|NNP|O (|(|(|O %|%|NN|O pred|pr|VBN|O )|)|)|O ,|,|,|O was|be|VBD|O found|find|VBN|O between|between|IN|O the|the|DT|O two|two|CD|O treatment|treatment|NN|O groups|group|NNS|O in|in|IN|O favor|favor|NN|O of|of|IN|O IFN-gamma-1b|IFN-gamma-1b|NN|O group|group|NN|O (|(|(|O p|p|NN|O =|=|JJ|O 0.04|0.04|CD|O )|)|)|O .|.|.|O 
In|in|IN|O addition|addition|NN|O ,|,|,|O the|the|DT|O IFN-gamma-1b|ifn-gamma-1b|JJ|O group|group|NN|O showed|show|VBD|O stability|stability|NN|O in|in|IN|O arterial|arterial|JJ|O PO2|PO2|NN|O while|while|IN|O the|the|DT|O colchicine|colchicine|NN|O group|group|NN|O significantly|significant|RB|O deteriorated|deteriorated|JJ|O (|(|(|O p|p|NN|O =|=|JJ|O 0.02|0.02|CD|O )|)|)|O .|.|.|O 
In|in|IN|O conclusion|conclusion|NN|O ,|,|,|O we|we|PRP|O report|report|VBP|O the|the|DT|O effect|effect|NN|O of|of|IN|O antifibrotic|antifibrotic|JJ|O agents|agent|NNS|O (|(|(|O IFN-gamma-1b|IFN-gamma-1b|NN|O and|and|CC|O colchicine|colchicine|NN|O )|)|)|O in|in|IN|O TGF-beta|TGF-beta|NN|GENE ,|,|,|O CTGF|Ctgf|NN|GENE ,|,|,|O and|and|CC|O endogenous|endogenous|JJ|O IFN-gamma|IFN-gamma|NN|GENE gene|gene|NN|O expression|expression|NN|O ,|,|,|O in|in|IN|O human|human|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
However|however|RB|O ,|,|,|O extended|extended|JJ|O studies|study|NNS|O are|be|VBP|O needed|need|VBN|O to|to|TO|O verify|verify|VB|O the|the|DT|O pathophysiological|pathophysiological|JJ|O consequences|consequence|NNS|O of|of|IN|O these|these|DT|O findings|finding|NNS|O .|.|.|O 
Nitric|nitric|JJ|O oxide|oxide|NN|O attenuates|attenuate|VBZ|O epithelial-mesenchymal|epithelial-mesenchymal|JJ|O transition|transition|NN|O in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O .|.|.|O 
Patients|patient|NNS|O with|with|IN|O interstitial|interstitial|JJ|O lung|lung|NN|O diseases|disease|NNS|O ,|,|,|O such|such|JJ|O as|as|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O and|and|CC|O bronchopulmonary|bronchopulmonary|JJ|O dysplasia|dysplasia|NN|O (|(|(|O BPD|BPD|NN|O )|)|)|O ,|,|,|O suffer|suffer|VBP|O from|from|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O secondary|secondary|JJ|O to|to|TO|O myofibroblast-mediated|myofibroblast-mediated|JJ|O excessive|excessive|JJ|O ECM|ecm|NN|O deposition|deposition|NN|O and|and|CC|O destruction|destruction|NN|O of|of|IN|O lung|lung|NN|O architecture|architecture|NN|O .|.|.|O 
Transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta1|beta1|NN|O induces|induce|VBZ|O epithelial-mesenchymal|epithelial-mesenchymal|JJ|O transition|transition|NN|O (|(|(|O EMT|emt|NN|GENE )|)|)|O of|of|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O (|(|(|O AEC|aec|NNS|O )|)|)|O to|to|TO|O myofibroblasts|myofibroblast|NNS|O both|both|CC|O in|in|FW|O vitro|vitro|FW|O and|and|CC|O in|in|FW|O vivo|vivo|FW|O .|.|.|O 
Inhaled|inhale|VBN|O nitric|nitric|JJ|O oxide|oxide|NN|O (|(|(|O NO|no|NN|O )|)|)|O attenuates|attenuate|VBZ|O ECM|ecm|NNP|O accumulation|accumulation|NN|O ,|,|,|O enhances|enhance|VBZ|O lung|lung|NN|O growth|growth|NN|O ,|,|,|O and|and|CC|O decreases|decrease|VBZ|O alveolar|alveolar|JJ|O myofibroblast|myofibroblast|NN|O number|number|NN|O in|in|IN|O experimental|experimental|JJ|O models|model|NNS|O .|.|.|O 
We|we|PRP|O therefore|therefore|RB|O hypothesized|hypothesise|VBD|O that|that|IN|O NO|no|NN|O attenuates|attenuate|VBZ|O TGF-beta1-induced|tgf-beta1-induced|JJ|O EMT|emt|NN|GENE in|in|IN|O cultured|culture|VBN|O AEC|aec|NN|O .|.|.|O 
Studies|study|NNS|O of|of|IN|O the|the|DT|O capacity|capacity|NN|O for|for|IN|O endogenous|endogenous|JJ|O NO|no|NN|O production|production|NN|O in|in|IN|O AEC|aec|NNP|O revealed|reveal|VBD|O that|that|IN|O endothelial|endothelial|JJ|O nitric|nitric|JJ|O oxide|oxide|NN|O synthase|synthase|NN|O (|(|(|O eNOS|enos|NN|O )|)|)|O and|and|CC|O inducible|inducible|JJ|O nitric|nitric|JJ|O oxide|oxide|NN|O synthase|synthase|NN|O (|(|(|O iNOS|inos|NN|O )|)|)|O are|be|VBP|O expressed|express|VBN|O and|and|CC|O active|active|JJ|O in|in|IN|O AEC|aec|NNP|O .|.|.|O 
Total|total|JJ|O NOS|nos|NN|GENE activity|activity|NN|O was|be|VBD|O 1.3|1.3|CD|O pmol|pmol|NN|O x|x|CC|O mg|mg|NN|O protein|protein|NN|O (|(|(|O -1|-1|CD|O )|)|)|O x|x|CC|O min|min|NN|O (|(|(|O -1|-1|CD|O )|)|)|O with|with|IN|O 67|67|CD|O %|%|NN|O derived|derive|VBN|O from|from|IN|O eNOS|enos|NN|O .|.|.|O 
TGF-beta1|TGF-beta1|NN|GENE (|(|(|O 50|50|CD|O pM|pm|NN|O )|)|)|O suppressed|suppress|VBD|O eNOS|enos|NN|O expression|expression|NN|O by|by|IN|O more|many|JJR|O than|than|IN|O 60|60|CD|O %|%|NN|O and|and|CC|O activity|activity|NN|O by|by|IN|O 83|83|CD|O %|%|NN|O but|but|CC|O did|do|VBD|O not|not|RB|O affect|affect|VB|O iNOS|inos|NN|O expression|expression|NN|O or|or|CC|O activity|activity|NN|O .|.|.|O 
Inhibition|inhibition|NN|O of|of|IN|O endogenous|endogenous|JJ|O NOS|nos|NN|GENE with|with|IN|O l-NAME|l-name|NN|O led|lead|VBD|O to|to|TO|O spontaneous|spontaneous|JJ|O EMT|emt|NN|GENE ,|,|,|O manifested|manifest|VBN|O by|by|IN|O increased|increase|VBN|O alpha-smooth-muscle-actin|alpha-smooth-muscle-actin|NN|GENE (|(|(|O alpha-SMA|alpha-SMA|NN|GENE )|)|)|O expression|expression|NN|O and|and|CC|O a|a|DT|O fibroblast-like|fibroblast-like|JJ|O morphology|morphology|NN|O .|.|.|O 
Provision|provision|NN|O of|of|IN|O exogenous|exogenous|JJ|O NO|no|NN|O to|to|TO|O TGF-beta1-treated|tgf-beta1-treated|JJ|O AEC|aec|NNS|O decreased|decrease|VBD|O stress|stress|NN|O fiber-associated|fiber-associated|JJ|O alpha-SMA|alpha-SMA|NN|GENE expression|expression|NN|O and|and|CC|O decreased|decrease|VBD|O collagen|collagen|NN|O I|i|NN|O expression|expression|NN|O by|by|IN|O 80|80|CD|O %|%|NN|O .|.|.|O 
NO-treated|no-treated|JJ|O AEC|aec|NNS|O also|also|RB|O retained|retain|VBD|O an|a|DT|O epithelial|epithelial|JJ|O morphology|morphology|NN|O and|and|CC|O expressed|express|VBD|O increased|increase|VBN|O lamellar|lamellar|NN|O protein|protein|NN|O ,|,|,|O E-cadherin|e-cadherin|NN|GENE ,|,|,|O and|and|CC|O pro-surfactant|pro-surfactant|JJ|O protein|protein|NN|O B|b|NN|O compared|compare|VBN|O with|with|IN|O those|those|DT|O treated|treat|VBN|O with|with|IN|O TGF-beta|TGF-beta|NN|GENE alone|alone|RB|O .|.|.|O 
These|these|DT|O findings|finding|NNS|O indicate|indicate|VBP|O that|that|IN|O NO|no|NN|O serves|serve|VBZ|O a|a|DT|O critical|critical|JJ|O role|role|NN|O in|in|IN|O preserving|preserve|VBG|O an|a|DT|O epithelial|epithelial|JJ|O phenotype|phenotype|NN|O and|and|CC|O in|in|IN|O attenuating|attenuate|VBG|O EMT|emt|NNP|GENE in|in|IN|O AEC|aec|NNP|O .|.|.|O 
NO-mediated|no-mediated|JJ|O regulation|regulation|NN|O of|of|IN|O AEC|aec|NNP|O fate|fate|NN|O may|may|MD|O have|have|VB|O important|important|JJ|O implications|implication|NNS|O in|in|IN|O the|the|DT|O pathophysiology|pathophysiology|NN|O and|and|CC|O treatment|treatment|NN|O of|of|IN|O diseases|disease|NNS|O such|such|JJ|O as|as|IN|O IPF|IPF|NN|O and|and|CC|O BPD|BPD|NN|O .|.|.|O 
p63|p63|NN|GENE -|-|:|O Key|key|NN|O molecule|molecule|NN|O in|in|IN|O the|the|DT|O early|early|JJ|O phase|phase|NN|O of|of|IN|O epithelial|epithelial|JJ|O abnormality|abnormality|NN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O the|the|DT|O most|much|RBS|O common|common|JJ|O lung|lung|NN|O disease|disease|NN|O predisposing|predispose|VBG|O lung|lung|NN|O cancer|cancer|NN|O .|.|.|O 
To|to|TO|O clarify|clarify|VB|O the|the|DT|O early|early|JJ|O phase|phase|NN|O of|of|IN|O epithelial|epithelial|JJ|O abnormalities|abnormality|NNS|O in|in|IN|O IPF|IPF|NN|O ,|,|,|O we|we|PRP|O used|use|VBD|O an|a|DT|O in|in|FW|O vitro|vitro|FW|O squamous|squamous|JJ|O metaplasia|metaplasia|NN|O model|model|NN|O ,|,|,|O transforming|transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O -|-|:|O treated|treat|VBN|O airway|airway|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O (|(|(|O BEAS-2B|BEAS-2B|NN|O )|)|)|O .|.|.|O 
The|the|DT|O model|model|NN|O repeated|repeat|VBD|O the|the|DT|O expression|expression|NN|O of|of|IN|O squamous|squamous|JJ|O epithelial|epithelial|JJ|O character|character|NN|O ,|,|,|O such|such|JJ|O as|as|IN|O involucrin|involucrin|NN|O ,|,|,|O and|and|CC|O keratin|keratin|NN|O 6|6|CD|O and|and|CC|O 14|14|CD|O .|.|.|O 
DNA|dna|NN|O microarray|microarray|NN|O analysis|analysis|NN|O disclosed|disclose|VBD|O a|a|DT|O unique|unique|JJ|O expression|expression|NN|O signature|signature|NN|O in|in|IN|O TGF-beta1-treated|tgf-beta1-treated|JJ|O airway|airway|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O ,|,|,|O 20|20|CD|O specifically|specific|RB|O up-regulated|upregulate|VBN|O genes|gene|NNS|O including|include|VBG|O p63|p63|NN|GENE ,|,|,|O jagged|jag|VBN|O 1|1|CD|O (|(|(|O jag1|jag1|NN|O )|)|)|O and|and|CC|O the|the|DT|O genes|gene|NNS|O of|of|IN|O structure|structure|NN|O proteins|protein|NNS|O .|.|.|O 
Western|western|NN|O blotting|blotting|NN|O and|and|CC|O RT-PCR|rt-pcr|NN|O analysis|analysis|NN|O revealed|reveal|VBD|O that|that|IN|O DeltaNp63alpha|DeltaNp63alpha|NN|O was|be|VBD|O the|the|DT|O dominant|dominant|JJ|O isoform|isoform|NN|O of|of|IN|O p63|p63|NN|GENE in|in|IN|O our|our|PRP$|O experimental|experimental|JJ|O model|model|NN|O .|.|.|O 
Immunohistochemical|immunohistochemical|JJ|O analysis|analysis|NN|O demonstrated|demonstrate|VBD|O the|the|DT|O expression|expression|NN|O of|of|IN|O p63|p63|NN|GENE and|and|CC|O jag1|jag1|NN|O in|in|IN|O lung|lung|NN|O tissues|tissue|NNS|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
Inhibition|inhibition|NN|O of|of|IN|O p63|p63|NN|GENE with|with|IN|O siRNA|siRNA|NN|O caused|cause|VBD|O the|the|DT|O down-regulation|down-regulation|NN|O of|of|IN|O jag1|jag1|NN|O expression|expression|NN|O ,|,|,|O but|but|CC|O not|not|RB|O of|of|IN|O involucrin|involucrin|NN|O ,|,|,|O or|or|CC|O keratin|keratin|NN|O 6|6|CD|O and|and|CC|O 14|14|CD|O .|.|.|O 
Interestingly|interesting|RB|O ,|,|,|O the|the|DT|O up-regulation|up-regulation|NN|O of|of|IN|O p63|p63|NN|GENE was|be|VBD|O totally|total|RB|O suppressed|suppress|VBN|O by|by|IN|O N-acetyl-l-cysteine|N-acetyl-l-cysteine|NN|O (|(|(|O NAC|nac|NN|O )|)|)|O ,|,|,|O but|but|CC|O not|not|RB|O by|by|IN|O dexamethasone|dexamethasone|NN|O or|or|CC|O pirfenidone|pirfenidone|NN|O .|.|.|O 
Thus|thus|RB|O ,|,|,|O the|the|DT|O p63-jag1|p63-jag1|NN|O pathway|pathway|NN|O may|may|MD|O be|be|VB|O up-regulated|upregulate|VBN|O at|at|IN|O an|a|DT|O early|early|JJ|O phase|phase|NN|O of|of|IN|O epithelial|epithelial|JJ|O abnormalities|abnormality|NNS|O in|in|IN|O IPF|IPF|NN|O ,|,|,|O which|which|WDT|O can|can|MD|O be|be|VB|O overcome|overcome|VBN|O by|by|IN|O NAC|nac|NN|O even|even|RB|O in|in|IN|O the|the|DT|O TGF-beta1-rich|tgf-beta1-rich|JJ|O milieu|milieu|NN|O .|.|.|O 
Angiotensin-TGF-beta-1|Angiotensin-TGF-beta-1|NN|O crosstalk|crosstalk|NN|O in|in|IN|O human|human|JJ|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O :|:|:|O autocrine|autocrine|JJ|O mechanisms|mechanism|NNS|O in|in|IN|O myofibroblasts|myofibroblast|NNS|O and|and|CC|O macrophages|macrophage|NNS|O .|.|.|O 
Angiotensin|Angiotensin|NN|GENE II|II|NN|GENE (|(|(|O ANGII|ANGII|NN|GENE )|)|)|O has|have|VBZ|O been|be|VBN|O identified|identify|VBN|O as|as|IN|O a|a|DT|O proapoptotic|proapoptotic|JJ|O and|and|CC|O profibrotic|profibrotic|JJ|O factor|factor|NN|O in|in|IN|O experimental|experimental|JJ|O lung|lung|NN|O fibrosis|fibrosis|NN|O models|model|NNS|O ,|,|,|O and|and|CC|O patients|patient|NNS|O with|with|IN|O the|the|DT|O ID/DD|ID/DD|NN|O polymorphism|polymorphism|NN|O of|of|IN|O ANG|ANG|NN|GENE converting|converting|NN|GENE enzyme|enzyme|NN|GENE (|(|(|O ACE|ace|NN|GENE )|)|)|O ,|,|,|O which|which|WDT|O confers|confer|VBZ|O higher|high|JJR|O levels|level|NNS|O of|of|IN|O ACE|ace|NN|GENE ,|,|,|O are|be|VBP|O predisposed|predispose|VBN|O to|to|TO|O lung|lung|NN|O fibrosis|fibrosis|NN|O (|(|(|O Hum|hum|NNP|O .|.|.|O 
Previous|previous|JJ|O work|work|NN|O from|from|IN|O this|this|DT|O laboratory|laboratory|NN|O has|have|VBZ|O shown|show|VBN|O that|that|IN|O human|human|JJ|O lung|lung|NN|O myofibroblasts|myofibroblast|NNS|O isolated|isolate|VBN|O from|from|IN|O patients|patient|NNS|O with|with|IN|O Idiopathic|idiopathic|JJ|O Pulmonary|pulmonary|JJ|O Fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O synthesize|synthesize|VBP|O the|the|DT|O ANGII|ANGII|NN|GENE precursor|precursor|NN|O angiotensinogen|angiotensinogen|NN|O (|(|(|O AGT|AGT|NN|O )|)|)|O constitutively|constitutive|RB|O .|.|.|O 
In|in|IN|O attempts|attempt|NNS|O to|to|TO|O understand|understand|VB|O the|the|DT|O mechanisms|mechanism|NNS|O and|and|CC|O consequences|consequence|NNS|O of|of|IN|O constitutive|constitutive|JJ|O AGT|AGT|NN|O synthesis|synthesis|NN|O by|by|IN|O myofibroblasts|myofibroblast|NNS|O ,|,|,|O we|we|PRP|O studied|study|VBD|O myofibroblast-rich|myofibroblast-rich|JJ|O primary|primary|JJ|O cultures|culture|NNS|O of|of|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O from|from|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O (|(|(|O HIPF|HIPF|NN|O isolates|isolate|NNS|O )|)|)|O ,|,|,|O primary|primary|JJ|O fibroblasts|fibroblast|NNS|O from|from|IN|O normal|normal|JJ|O human|human|JJ|O lung|lung|NN|O (|(|(|O NLFs|nlf|NNS|O )|)|)|O ,|,|,|O the|the|DT|O IMR90|IMR90|NN|O and|and|CC|O WI38|WI38|NN|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O cell|cell|NN|O lines|line|NNS|O ,|,|,|O and|and|CC|O paraffin|paraffin|NN|O sections|section|NNS|O of|of|IN|O lung|lung|NN|O biopsies|biopsy|NNS|O from|from|IN|O patients|patient|NNS|O with|with|IN|O IPF|IPF|NN|O .|.|.|O 
Compared|compare|VBN|O to|to|TO|O the|the|DT|O normal|normal|JJ|O NLF|NLF|NN|O isolates|isolate|NNS|O ,|,|,|O HIPF|HIPF|NN|O primary|primary|JJ|O fibroblast|fibroblast|NN|O isolates|isolate|NNS|O constitutively|constitutive|RB|O synthesized|synthesize|VBN|O more|many|JJR|O AGT|AGT|NN|O and|and|CC|O TGF-beta1|TGF-beta1|NN|GENE mRNA|mRNA|NN|O ,|,|,|O and|and|CC|O released|release|VBD|O more|many|JJR|O AGT|AGT|NN|O protein|protein|NN|O ,|,|,|O ANGII|ANGII|NN|GENE and|and|CC|O active|active|JJ|O TGF-beta1|TGF-beta1|NN|GENE protein|protein|NN|O into|into|IN|O serum-free|serum-free|JJ|O conditioned|condition|VBN|O media|medium|NNS|O (|(|(|O both|both|CC|O p|p|NN|O <|<|JJR|O 0.01|0.01|CD|O )|)|)|O .|.|.|O 
Incubation|incubation|NN|O of|of|IN|O HIPF|HIPF|NN|O fibrotic|fibrotic|JJ|O isolates|isolate|NNS|O with|with|IN|O the|the|DT|O ANGII|ANGII|NN|GENE receptor|receptor|NN|O antagonist|antagonist|NN|O saralasin|saralasin|NN|O reduced|reduce|VBD|O both|both|CC|O TGF-beta1|TGF-beta1|NN|GENE mRNA|mRNA|NN|O and|and|CC|O active|active|JJ|O protein|protein|NN|O ,|,|,|O suggesting|suggest|VBG|O that|that|IN|O the|the|DT|O constitutive|constitutive|JJ|O expression|expression|NN|O of|of|IN|O AGT|AGT|NN|O drives|drive|VBZ|O the|the|DT|O higher|high|JJR|O expression|expression|NN|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE by|by|IN|O the|the|DT|O HIPF|HIPF|NN|O cells|cell|NNS|O .|.|.|O 
Consistent|consistent|JJ|O with|with|IN|O this|this|DT|O premise|premise|NN|O ,|,|,|O treatment|treatment|NN|O of|of|IN|O either|either|CC|O the|the|DT|O primary|primary|JJ|O NLFs|nlf|NNS|O or|or|CC|O the|the|DT|O WI38|WI38|NN|O cell|cell|NN|O line|line|NN|O with|with|IN|O 10|10|CD|O (|(|(|O -7|-7|CD|O )|)|)|O M|m|NN|O ANGII|ANGII|NN|GENE increased|increase|VBD|O both|both|CC|O TGF-beta1|TGF-beta1|NN|GENE mRNA|mRNA|NN|O and|and|CC|O soluble|soluble|JJ|O active|active|JJ|O TGF-beta1|TGF-beta1|NN|GENE protein|protein|NN|O .|.|.|O 
Moreover|moreover|RB|O ,|,|,|O induction|induction|NN|O of|of|IN|O the|the|DT|O myofibroblast|myofibroblast|NN|O transition|transition|NN|O in|in|IN|O the|the|DT|O IMR90|IMR90|NN|O cell|cell|NN|O line|line|NN|O with|with|IN|O 2|2|CD|O ng/ml|ng/ml|NN|O TGF-beta1|TGF-beta1|NN|GENE increased|increase|VBD|O steady|steady|JJ|O state|state|NN|O AGT|AGT|NN|O mRNA|mRNA|NN|O levels|level|NNS|O by|by|IN|O realtime|realtime|NN|O PCR|pcr|NN|O (|(|(|O 8-fold|8-fold|JJ|O ,|,|,|O p|p|NN|O <|<|JJR|O 0.01|0.01|CD|O )|)|)|O and|and|CC|O induced|induce|VBN|O expression|expression|NN|O of|of|IN|O an|a|DT|O AGT|AGT|NN|O promoter-luciferase|promoter-luciferase|NN|O reporter|reporter|NN|O construct|construct|NN|O by|by|IN|O over|over|IN|O 10-fold|10-fold|JJ|O (|(|(|O p|p|NN|O <|<|JJR|O 0.001|0.001|CD|O )|)|)|O .|.|.|O 
Antisense|antisense|JJ|O oligonucleotides|oligonucleotide|NNS|O against|against|IN|O TGF-beta1|TGF-beta1|NN|GENE mRNA|mRNA|NN|O or|or|CC|O TGF-beta|TGF-beta|NN|GENE neutralizing|neutralizing|NN|O antibodies|antibody|NNS|O ,|,|,|O when|when|WRB|O applied|apply|VBN|O to|to|TO|O the|the|DT|O fibrotic|fibrotic|JJ|O HIPF|HIPF|NN|O cells|cell|NNS|O in|in|IN|O serum-free|serum-free|JJ|O medium|medium|NN|O ,|,|,|O significantly|significant|RB|O reduced|reduce|VBD|O AGT|AGT|NN|O expression|expression|NN|O .|.|.|O 
In|in|IN|O lung|lung|NN|O sections|section|NNS|O from|from|IN|O IPF|IPF|NN|O patient|patient|NN|O biopsies|biopsy|NNS|O ,|,|,|O immunoreactive|immunoreactive|JJ|O AGT/ANGI|AGT/ANGI|NN|O proteins|protein|NNS|O were|be|VBD|O detected|detect|VBN|O in|in|IN|O myofibroblasts|myofibroblast|NNS|O ,|,|,|O epithelial|epithelial|JJ|O cells|cell|NNS|O and|and|CC|O presumptive|presumptive|JJ|O alveolar|alveolar|JJ|O macrophages|macrophage|NNS|O .|.|.|O 
Together|together|RB|O ,|,|,|O these|these|DT|O data|datum|NNS|O support|support|VBP|O the|the|DT|O existence|existence|NN|O of|of|IN|O an|a|DT|O angiotensin/TGF-beta|angiotensin/TGF-beta|NN|O 1|1|CD|O ``|``|``|O autocrine|autocrine|JJ|O loop|loop|NN|O ''|''|''|O in|in|IN|O human|human|JJ|O lung|lung|NN|O myofibroblasts|myofibroblast|NNS|O and|and|CC|O also|also|RB|O suggest|suggest|VBP|O ANG|ang|NN|O peptide|peptide|NN|O expression|expression|NN|O by|by|IN|O epithelia|epithelium|NN|O and|and|CC|O macrophages|macrophage|NNS|O in|in|IN|O the|the|DT|O IPF|IPF|NN|O lung|lung|NN|O .|.|.|O 
These|these|DT|O findings|finding|NNS|O may|may|MD|O explain|explain|VB|O the|the|DT|O ability|ability|NN|O of|of|IN|O ACE|ace|NN|GENE inhibitors|inhibitor|NNS|O and|and|CC|O ANG|ang|NN|O receptor|receptor|NN|O antagonists|antagonist|NNS|O to|to|TO|O block|block|VB|O experimental|experimental|JJ|O lung|lung|NN|O fibrosis|fibrosis|NN|O in|in|IN|O animals|animal|NNS|O ,|,|,|O and|and|CC|O support|support|VBP|O the|the|DT|O need|need|NN|O for|for|IN|O evaluation|evaluation|NN|O of|of|IN|O these|these|DT|O agents|agent|NNS|O for|for|IN|O potential|potential|JJ|O treatment|treatment|NN|O of|of|IN|O human|human|JJ|O IPF|IPF|NN|O .|.|.|O 
This|this|DT|O manuscript|manuscript|NN|O discusses|discuss|VBZ|O the|the|DT|O data|datum|NNS|O described|describe|VBN|O above|above|IN|O and|and|CC|O their|their|PRP$|O implications|implication|NNS|O regarding|regard|VBG|O IPF|IPF|NN|O pathogenesis|pathogenesis|NN|O .|.|.|O 
Thalidomide|thalidomide|NNP|O prevents|prevent|VBZ|O bleomycin-induced|bleomycin-induced|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O mice|mouse|NNS|O .|.|.|O 
Pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O humans|human|NNS|O can|can|MD|O occur|occur|VB|O as|as|IN|O a|a|DT|O result|result|NN|O of|of|IN|O a|a|DT|O large|large|JJ|O number|number|NN|O of|of|IN|O conditions|condition|NNS|O .|.|.|O 
In|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O pulmonary|pulmonary|JJ|O function|function|NN|O becomes|become|VBZ|O progressively|progressive|RB|O compromised|compromise|VBN|O resulting|result|VBG|O in|in|IN|O a|a|DT|O high|high|JJ|O mortality|mortality|NN|O rate|rate|NN|O .|.|.|O 
Currently|current|RB|O there|there|EX|O are|be|VBP|O no|no|DT|O proven|proven|JJ|O effective|effective|JJ|O treatments|treatment|NNS|O for|for|IN|O IPF|IPF|NN|O .|.|.|O 
We|we|PRP|O have|have|VBP|O recently|recent|RB|O reported|report|VBN|O that|that|IN|O IL-6|IL-6|NN|GENE and|and|CC|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O plays|play|VBZ|O an|a|DT|O important|important|JJ|O role|role|NN|O in|in|IN|O proliferation|proliferation|NN|O and|and|CC|O differentiation|differentiation|NN|O of|of|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O and|and|CC|O all-trans-retinoic|all-trans-retinoic|JJ|O acid|acid|NN|O (|(|(|O ATRA|ATRA|NN|O )|)|)|O prevented|prevent|VBD|O bleomycin-induced|bleomycin-induced|JJ|O lung|lung|NN|O fibrosis|fibrosis|NN|O through|through|IN|O the|the|DT|O inhibition|inhibition|NN|O of|of|IN|O these|these|DT|O cytokines|cytokine|NNS|O .|.|.|O 
Thalidomide|thalidomide|NNP|O (|(|(|O Thal|Thal|NNP|O )|)|)|O has|have|VBZ|O been|be|VBN|O used|use|VBN|O in|in|IN|O the|the|DT|O treatment|treatment|NN|O of|of|IN|O multiple|multiple|JJ|O myeloma|myeloma|NN|O through|through|IN|O the|the|DT|O inhibitory|inhibitory|JJ|O effect|effect|NN|O on|on|IN|O IL-6-dependent|il-6-dependent|JJ|O cell|cell|NN|O growth|growth|NN|O and|and|CC|O angiogenesis|angiogenesis|NN|O .|.|.|O 
In|in|IN|O this|this|DT|O study|study|NN|O ,|,|,|O we|we|PRP|O examined|examine|VBD|O the|the|DT|O preventive|preventive|JJ|O effect|effect|NN|O of|of|IN|O Thal|Thal|NNP|O on|on|IN|O bleomycin-induced|bleomycin-induced|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O mice|mouse|NNS|O .|.|.|O 
We|we|PRP|O performed|perform|VBD|O histological|histological|JJ|O examinations|examination|NNS|O and|and|CC|O quantitative|quantitative|JJ|O measurements|measurement|NNS|O of|of|IN|O IL-6|IL-6|NN|GENE ,|,|,|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O ,|,|,|O collagen|collagen|NN|O type|type|NN|O Ialpha1|Ialpha1|NN|O (|(|(|O COL1A1|COL1A1|NN|GENE )|)|)|O ,|,|,|O vascular|vascular|NN|GENE endothelial|endothelial|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE (|(|(|O VEGF|vegf|NN|GENE )|)|)|O ,|,|,|O angiopoietin-1|angiopoietin-1|NN|O (|(|(|O Ang-1|Ang-1|NN|O )|)|)|O and|and|CC|O angiopoietin-2|angiopoietin-2|NN|O (|(|(|O Ang-2|Ang-2|NN|O )|)|)|O in|in|IN|O bleomycin-treated|bleomycin-treated|JJ|O mouse|mouse|NN|O lung|lung|NN|O tissues|tissue|NNS|O with|with|IN|O or|or|CC|O without|without|IN|O the|the|DT|O administration|administration|NN|O of|of|IN|O Thal|Thal|NNP|O .|.|.|O 
Thal|Thal|NNP|O histologically|histological|RB|O ameliorated|ameliorate|VBD|O bleomycin-induced|bleomycin-induced|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O mouse|mouse|NN|O lung|lung|NN|O tissues|tissue|NNS|O .|.|.|O 
Thal|Thal|NNP|O decreased|decrease|VBD|O the|the|DT|O expressions|expression|NNS|O of|of|IN|O IL-6|IL-6|NN|GENE ,|,|,|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O ,|,|,|O VEGF|vegf|NN|GENE ,|,|,|O Ang-1|Ang-1|NN|O Ang-2|Ang-2|NN|O ,|,|,|O and|and|CC|O COL1A1|COL1A1|NN|GENE mRNA|mRNA|NN|O in|in|IN|O mouse|mouse|NN|O lung|lung|NN|O tissues|tissue|NNS|O .|.|.|O 
In|in|IN|O addition|addition|NN|O ,|,|,|O Thal|Thal|NNP|O inhibited|inhibit|VBD|O angiogenesis|angiogenesis|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O .|.|.|O 
In|in|FW|O vitro|vitro|FW|O studies|study|NNS|O disclosed|disclose|VBD|O that|that|IN|O Thal|Thal|NNP|O reduced|reduce|VBD|O 1|1|CD|O )|)|)|O production|production|NN|O of|of|IN|O IL-6|IL-6|NN|GENE ,|,|,|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O ,|,|,|O VEGF|vegf|NN|GENE ,|,|,|O Ang-1|Ang-1|NN|O ,|,|,|O and|and|CC|O collagen|collagen|NN|O synthesis|synthesis|NN|O from|from|IN|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O and|and|CC|O 2|2|LS|O )|)|)|O both|both|CC|O IL-6-dependent|il-6-dependent|JJ|O proliferation|proliferation|NN|O and|and|CC|O TGF-beta|TGF-beta|NN|GENE (|(|(|O 1|1|CD|O )|)|)|O -|-|:|O dependent|dependent|JJ|O transdifferentiation|transdifferentiation|NN|O of|of|IN|O the|the|DT|O cells|cell|NNS|O ,|,|,|O which|which|WDT|O could|can|MD|O be|be|VB|O the|the|DT|O mechanism|mechanism|NN|O underlying|underlie|VBG|O the|the|DT|O preventive|preventive|JJ|O effect|effect|NN|O of|of|IN|O Thal|Thal|NNP|O on|on|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
These|these|DT|O data|datum|NNS|O may|may|MD|O provide|provide|VB|O a|a|DT|O rationale|rationale|NN|O to|to|TO|O explore|explore|VB|O clinical|clinical|JJ|O use|use|NN|O of|of|IN|O Thal|Thal|NNP|O for|for|IN|O the|the|DT|O prevention|prevention|NN|O of|of|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
TGF-beta-induced|tgf-beta-induced|JJ|O EMT|emt|NN|GENE :|:|:|O mechanisms|mechanism|NNS|O and|and|CC|O implications|implication|NNS|O for|for|IN|O fibrotic|fibrotic|JJ|O lung|lung|NN|O disease|disease|NN|O .|.|.|O 
Epithelial-mesenchymal|epithelial-mesenchymal|JJ|O transition|transition|NN|O (|(|(|O EMT|emt|NN|GENE )|)|)|O ,|,|,|O a|a|DT|O process|process|NN|O whereby|whereby|WRB|O fully|full|RB|O differentiated|differentiate|VBN|O epithelial|epithelial|JJ|O cells|cell|NNS|O undergo|undergo|VBP|O transition|transition|NN|O to|to|TO|O a|a|DT|O mesenchymal|mesenchymal|JJ|O phenotype|phenotype|NN|O giving|give|VBG|O rise|rise|NN|O to|to|TO|O fibroblasts|fibroblast|NNS|O and|and|CC|O myofibroblasts|myofibroblast|NNS|O ,|,|,|O is|be|VBZ|O increasingly|increasing|RB|O recognized|recognize|VBN|O as|as|IN|O playing|play|VBG|O an|a|DT|O important|important|JJ|O role|role|NN|O in|in|IN|O repair|repair|NN|O and|and|CC|O scar|scar|NN|O formation|formation|NN|O following|follow|VBG|O epithelial|epithelial|JJ|O injury|injury|NN|O .|.|.|O 
The|the|DT|O extent|extent|NN|O to|to|TO|O which|which|WDT|O this|this|DT|O process|process|NN|O contributes|contribute|VBZ|O to|to|TO|O fibrosis|fibrosis|NN|O following|follow|VBG|O injury|injury|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O is|be|VBZ|O a|a|DT|O subject|subject|NN|O of|of|IN|O active|active|JJ|O investigation|investigation|NN|O .|.|.|O 
Recently|recent|RB|O ,|,|,|O it|it|PRP|O was|be|VBD|O demonstrated|demonstrate|VBN|O that|that|IN|O transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta|beta|NN|O induces|induce|VBZ|O EMT|emt|NNP|GENE in|in|IN|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O (|(|(|O AEC|aec|NNS|O )|)|)|O in|in|FW|O vitro|vitro|FW|O and|and|CC|O in|in|FW|O vivo|vivo|FW|O ,|,|,|O and|and|CC|O epithelial|epithelial|JJ|O and|and|CC|O mesenchymal|mesenchymal|JJ|O markers|marker|NNS|O have|have|VBP|O been|be|VBN|O colocalized|colocalize|VBN|O to|to|TO|O hyperplastic|hyperplastic|JJ|O type|type|NN|O II|II|CD|O (|(|(|O AT2|AT2|NN|GENE )|)|)|O cells|cell|NNS|O in|in|IN|O lung|lung|NN|O tissue|tissue|NN|O from|from|IN|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O ,|,|,|O suggesting|suggest|VBG|O that|that|IN|O AEC|aec|NNP|O may|may|MD|O exhibit|exhibit|VB|O extreme|extreme|JJ|O plasticity|plasticity|NN|O and|and|CC|O serve|serve|VB|O as|as|IN|O a|a|DT|O source|source|NN|O of|of|IN|O fibroblasts|fibroblast|NNS|O and/or|and/or|CC|O myofibroblasts|myofibroblast|NNS|O in|in|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O .|.|.|O 
In|in|IN|O this|this|DT|O review|review|NN|O ,|,|,|O we|we|PRP|O describe|describe|VBP|O the|the|DT|O characteristic|characteristic|JJ|O features|feature|NNS|O of|of|IN|O EMT|emt|NN|GENE and|and|CC|O its|its|PRP$|O mechanistic|mechanistic|JJ|O underpinnings|underpinning|NNS|O .|.|.|O 
We|we|PRP|O further|further|RB|O describe|describe|VBP|O the|the|DT|O contribution|contribution|NN|O of|of|IN|O EMT|emt|NN|GENE to|to|TO|O fibrosis|fibrosis|NN|O in|in|IN|O adult|adult|JJ|O tissues|tissue|NNS|O following|follow|VBG|O injury|injury|NN|O ,|,|,|O focusing|focus|VBG|O especially|especial|RB|O on|on|IN|O the|the|DT|O critical|critical|JJ|O role|role|NN|O of|of|IN|O TGF-beta|TGF-beta|NN|GENE and|and|CC|O its|its|PRP$|O downstream|downstream|JJ|O mediators|mediator|NNS|O in|in|IN|O this|this|DT|O process|process|NN|O .|.|.|O 
Finally|final|RB|O ,|,|,|O we|we|PRP|O highlight|highlight|VBP|O recent|recent|JJ|O descriptions|description|NNS|O of|of|IN|O EMT|emt|NN|GENE in|in|IN|O the|the|DT|O lung|lung|NN|O and|and|CC|O the|the|DT|O potential|potential|JJ|O implications|implication|NNS|O of|of|IN|O this|this|DT|O process|process|NN|O for|for|IN|O the|the|DT|O treatment|treatment|NN|O of|of|IN|O fibrotic|fibrotic|JJ|O lung|lung|NN|O disease|disease|NN|O .|.|.|O 
Treatment|treatment|NN|O for|for|IN|O fibrosis|fibrosis|NN|O of|of|IN|O the|the|DT|O lung|lung|NN|O in|in|IN|O diseases|disease|NNS|O such|such|JJ|O as|as|IN|O IPF|IPF|NN|O has|have|VBZ|O heretofore|heretofore|RB|O focused|focus|VBN|O largely|large|RB|O on|on|IN|O amelioration|amelioration|NN|O of|of|IN|O potential|potential|JJ|O inciting|incite|VBG|O processes|process|NNS|O such|such|JJ|O as|as|IN|O inflammation|inflammation|NN|O .|.|.|O 
It|it|PRP|O is|be|VBZ|O hoped|hope|VBN|O that|that|IN|O this|this|DT|O review|review|NN|O will|will|MD|O stimulate|stimulate|VB|O further|further|JJ|O consideration|consideration|NN|O of|of|IN|O the|the|DT|O cellular|cellular|JJ|O mechanisms|mechanism|NNS|O of|of|IN|O fibrogenesis|fibrogenesis|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O and|and|CC|O especially|especial|RB|O the|the|DT|O role|role|NN|O of|of|IN|O the|the|DT|O epithelium|epithelium|NN|O in|in|IN|O this|this|DT|O process|process|NN|O ,|,|,|O potentially|potential|RB|O leading|lead|VBG|O to|to|TO|O innovative|innovative|JJ|O avenues|avenue|NNS|O of|of|IN|O investigation|investigation|NN|O and|and|CC|O treatment|treatment|NN|O .|.|.|O 
The|the|DT|O Role|role|NN|O of|of|IN|O PPARs|ppar|NNS|O in|in|IN|O Lung|lung|NN|O Fibrosis|fibrosis|NN|O .|.|.|O 
Pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O is|be|VBZ|O a|a|DT|O group|group|NN|O of|of|IN|O disorders|disorder|NNS|O characterized|characterize|VBN|O by|by|IN|O accumulation|accumulation|NN|O of|of|IN|O scar|scar|NN|O tissue|tissue|NN|O in|in|IN|O the|the|DT|O lung|lung|NN|O interstitium|interstitium|NN|O ,|,|,|O resulting|result|VBG|O in|in|IN|O loss|loss|NN|O of|of|IN|O alveolar|alveolar|JJ|O function|function|NN|O ,|,|,|O destruction|destruction|NN|O of|of|IN|O normal|normal|JJ|O lung|lung|NN|O architecture|architecture|NN|O ,|,|,|O and|and|CC|O respiratory|respiratory|JJ|O distress|distress|NN|O .|.|.|O 
Some|some|DT|O types|type|NNS|O of|of|IN|O fibrosis|fibrosis|NN|O respond|respond|VBP|O to|to|TO|O corticosteroids|corticosteroid|NNS|O ,|,|,|O but|but|CC|O for|for|IN|O many|many|JJ|O there|there|EX|O are|be|VBP|O no|no|DT|O effective|effective|JJ|O treatments|treatment|NNS|O .|.|.|O 
Prognosis|prognosis|NN|O varies|vary|VBZ|O but|but|CC|O can|can|MD|O be|be|VB|O poor|poor|JJ|O .|.|.|O 
For|for|IN|O example|example|NN|O ,|,|,|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O have|have|VBP|O a|a|DT|O median|median|JJ|O survival|survival|NN|O of|of|IN|O only|only|RB|O 2.9|2.9|CD|O years|year|NNS|O .|.|.|O 
Prognosis|prognosis|NN|O may|may|MD|O be|be|VB|O better|well|RBR|O in|in|IN|O patients|patient|NNS|O with|with|IN|O some|some|DT|O other|other|JJ|O types|type|NNS|O of|of|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O ,|,|,|O and|and|CC|O there|there|EX|O is|be|VBZ|O variability|variability|NN|O in|in|IN|O survival|survival|NN|O even|even|RB|O among|among|IN|O individuals|individual|NNS|O with|with|IN|O biopsy-proven|biopsy-proven|JJ|O IPF|IPF|NN|O .|.|.|O 
Evidence|evidence|NN|O is|be|VBZ|O accumulating|accumulate|VBG|O that|that|IN|O the|the|DT|O peroxisome|peroxisome|NN|O proliferator-activated|proliferator-activated|JJ|O receptors|receptor|NNS|O (|(|(|O PPARs|ppar|NNS|O )|)|)|O play|play|VBP|O important|important|JJ|O roles|role|NNS|O in|in|IN|O regulating|regulate|VBG|O processes|process|NNS|O related|relate|VBN|O to|to|TO|O fibrogenesis|fibrogenesis|NN|O ,|,|,|O including|include|VBG|O cellular|cellular|JJ|O differentiation|differentiation|NN|O ,|,|,|O inflammation|inflammation|NN|O ,|,|,|O and|and|CC|O wound|wound|NN|O healing|healing|NN|O .|.|.|O 
PPARalpha|PPARalpha|NN|O agonists|agonist|NNS|O ,|,|,|O including|include|VBG|O the|the|DT|O hypolidipemic|hypolidipemic|JJ|O fibrate|fibrate|NN|O drugs|drug|NNS|O ,|,|,|O inhibit|inhibit|VBP|O the|the|DT|O production|production|NN|O of|of|IN|O collagen|collagen|NN|O by|by|IN|O hepatic|hepatic|JJ|O stellate|stellate|NN|O cells|cell|NNS|O and|and|CC|O inhibit|inhibit|VBP|O liver|liver|NN|O ,|,|,|O kidney|kidney|NN|O ,|,|,|O and|and|CC|O cardiac|cardiac|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O animal|animal|NN|O models|model|NNS|O .|.|.|O 
In|in|IN|O the|the|DT|O mouse|mouse|NN|O model|model|NN|O of|of|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O induced|induce|VBN|O by|by|IN|O bleomycin|bleomycin|NN|O ,|,|,|O a|a|DT|O PPARalpha|PPARalpha|NN|O agonist|agonist|NN|O significantly|significant|RB|O inhibited|inhibit|VBD|O the|the|DT|O fibrotic|fibrotic|JJ|O response|response|NN|O ,|,|,|O while|while|IN|O PPARalpha|PPARalpha|NN|O knockout|knockout|NN|O mice|mouse|NNS|O developed|develop|VBD|O more|much|RBR|O serious|serious|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
PPARbeta/delta|PPARbeta/delta|NN|O appears|appear|VBZ|O to|to|TO|O play|play|VB|O a|a|DT|O critical|critical|JJ|O role|role|NN|O in|in|IN|O regulating|regulate|VBG|O the|the|DT|O transition|transition|NN|O from|from|IN|O inflammation|inflammation|NN|O to|to|TO|O wound|wind|VB|O healing|healing|NN|O .|.|.|O 
PPARbeta/delta|PPARbeta/delta|NN|O agonists|agonist|NNS|O inhibit|inhibit|VBP|O lung|lung|NN|O fibroblast|fibroblast|NN|O proliferation|proliferation|NN|O and|and|CC|O enhance|enhance|VBP|O the|the|DT|O antifibrotic|antifibrotic|JJ|O properties|property|NNS|O of|of|IN|O PPARgamma|PPARgamma|NN|O agonists|agonist|NNS|O .|.|.|O 
PPARgamma|PPARgamma|NN|O ligands|ligand|NNS|O oppose|oppose|VBP|O the|the|DT|O profibrotic|profibrotic|JJ|O effect|effect|NN|O of|of|IN|O TGF-beta|TGF-beta|NN|GENE ,|,|,|O which|which|WDT|O induces|induce|VBZ|O differentiation|differentiation|NN|O of|of|IN|O fibroblasts|fibroblast|NNS|O to|to|TO|O myofibroblasts|myofibroblast|NNS|O ,|,|,|O a|a|DT|O critical|critical|JJ|O effector|effector|NN|O cell|cell|NN|O in|in|IN|O fibrosis|fibrosis|NN|O .|.|.|O 
PPARgamma|PPARgamma|NN|O ligands|ligand|NNS|O ,|,|,|O including|include|VBG|O the|the|DT|O thiazolidinedione|thiazolidinedione|JJ|O class|class|NN|O of|of|IN|O antidiabetic|antidiabetic|JJ|O drugs|drug|NNS|O ,|,|,|O effectively|effective|RB|O inhibit|inhibit|VBP|O lung|lung|NN|O fibrosis|fibrosis|NN|O in|in|FW|O vitro|vitro|FW|O and|and|CC|O in|in|IN|O animal|animal|NN|O models|model|NNS|O .|.|.|O 
The|the|DT|O clinical|clinical|JJ|O availability|availability|NN|O of|of|IN|O potent|potent|JJ|O and|and|CC|O selective|selective|JJ|O PPARalpha|PPARalpha|NN|O and|and|CC|O PPARgamma|PPARgamma|NN|O agonists|agonist|NNS|O should|shall|MD|O facilitate|facilitate|VB|O rapid|rapid|JJ|O development|development|NN|O of|of|IN|O successful|successful|JJ|O treatment|treatment|NN|O strategies|strategy|NNS|O based|base|VBN|O on|on|IN|O current|current|JJ|O and|and|CC|O ongoing|ongoing|JJ|O research|research|NN|O .|.|.|O 
Molecular|molecular|JJ|O targets|target|NNS|O in|in|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O :|:|:|O the|the|DT|O myofibroblast|myofibroblast|NN|O in|in|IN|O focus|focus|NN|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O is|be|VBZ|O one|one|CD|O of|of|IN|O a|a|DT|O group|group|NN|O of|of|IN|O interstitial|interstitial|JJ|O lung|lung|NN|O diseases|disease|NNS|O that|that|WDT|O are|be|VBP|O characterized|characterize|VBN|O by|by|IN|O excessive|excessive|JJ|O matrix|matrix|NN|O deposition|deposition|NN|O and|and|CC|O destruction|destruction|NN|O of|of|IN|O the|the|DT|O normal|normal|JJ|O lung|lung|NN|O architecture|architecture|NN|O .|.|.|O 
Long-term|long-term|JJ|O survival|survival|NN|O of|of|IN|O IPF|IPF|NN|O patients|patient|NNS|O is|be|VBZ|O poor|poor|JJ|O ,|,|,|O with|with|IN|O a|a|DT|O 5-year|5-year|JJ|O survival|survival|NN|O rate|rate|NN|O of|of|IN|O only|only|RB|O 20|20|CD|O %|%|NN|O .|.|.|O 
Despite|despite|IN|O a|a|DT|O lack|lack|NN|O of|of|IN|O evidence-based|evidence-based|JJ|O benefit|benefit|NN|O ,|,|,|O IPF|IPF|NN|O has|have|VBZ|O historically|historically|RB|O been|be|VBN|O treated|treat|VBN|O with|with|IN|O corticosteroids|corticosteroid|NNS|O and/or|and/or|CC|O cytotoxic|cytotoxic|JJ|O agents|agent|NNS|O such|such|JJ|O as|as|IN|O prednisone|prednisone|NN|O .|.|.|O 
Given|give|VBN|O the|the|DT|O poor|poor|JJ|O efficacy|efficacy|NN|O of|of|IN|O these|these|DT|O drugs|drug|NNS|O ,|,|,|O novel|novel|JJ|O therapeutic|therapeutic|JJ|O strategies|strategy|NNS|O are|be|VBP|O required|require|VBN|O for|for|IN|O the|the|DT|O management|management|NN|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
This|this|DT|O demands|demand|VBZ|O a|a|DT|O better|good|JJR|O understanding|understanding|NN|O of|of|IN|O the|the|DT|O molecular|molecular|JJ|O mechanisms|mechanism|NNS|O underlying|underlie|VBG|O the|the|DT|O pathogenesis|pathogenesis|NN|O and|and|CC|O progression|progression|NN|O of|of|IN|O this|this|DT|O disease|disease|NN|O .|.|.|O 
The|the|DT|O primary|primary|JJ|O effector|effector|NN|O cell|cell|NN|O in|in|IN|O fibrosis|fibrosis|NN|O is|be|VBZ|O the|the|DT|O myofibroblast|myofibroblast|NN|O ;|;|:|O these|these|DT|O cells|cell|NNS|O are|be|VBP|O highly|high|RB|O synthetic|synthetic|JJ|O for|for|IN|O collagen|collagen|NN|O ,|,|,|O have|have|VBP|O a|a|DT|O contractile|contractile|JJ|O phenotype|phenotype|NN|O ,|,|,|O and|and|CC|O are|be|VBP|O characterized|characterize|VBN|O by|by|IN|O the|the|DT|O presence|presence|NN|O of|of|IN|O alpha-smooth-muscle-actin|alpha-smooth-muscle-actin|JJ|GENE stress|stress|NN|O fibers|fiber|NNS|O .|.|.|O 
They|they|PRP|O may|may|MD|O be|be|VB|O derived|derive|VBN|O by|by|IN|O activation/proliferation|activation/proliferation|NN|O of|of|IN|O resident|resident|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O epithelial-mesenchymal|epithelial-mesenchymal|JJ|O differentiation|differentiation|NN|O ,|,|,|O or|or|CC|O recruitment|recruitment|NN|O of|of|IN|O circulating|circulate|VBG|O fibroblastic|fibroblastic|JJ|O stem|stem|NN|O cells|cell|NNS|O (|(|(|O fibrocytes|fibrocyte|NNS|O )|)|)|O .|.|.|O 
From|from|IN|O a|a|DT|O therapeutic|therapeutic|JJ|O viewpoint|viewpoint|NN|O ,|,|,|O interfering|interfere|VBG|O with|with|IN|O the|the|DT|O pathways|pathway|NNS|O that|that|WDT|O lead|lead|VBP|O to|to|TO|O myofibroblast|myofibroblast|JJ|O expansion|expansion|NN|O should|shall|MD|O be|be|VB|O of|of|IN|O considerable|considerable|JJ|O benefit|benefit|NN|O in|in|IN|O the|the|DT|O treatment|treatment|NN|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
This|this|DT|O review|review|NN|O will|will|MD|O highlight|highlight|VB|O some|some|DT|O of|of|IN|O the|the|DT|O key|key|JJ|O molecules|molecule|NNS|O involved|involve|VBN|O in|in|IN|O this|this|DT|O process|process|NN|O and|and|CC|O the|the|DT|O clinical|clinical|JJ|O trials|trial|NNS|O that|that|WDT|O have|have|VBP|O ensued|ensue|VBN|O .|.|.|O 
Gremlin-mediated|gremlin-mediated|JJ|O decrease|decrease|NN|O in|in|IN|O bone|bone|NN|GENE morphogenetic|morphogenetic|NN|GENE protein|protein|NN|GENE signaling|signaling|NN|O promotes|promote|VBZ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
RATIONALE|rationale|NN|O :|:|:|O Members|member|NNS|O of|of|IN|O the|the|DT|O transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta|beta|NN|O superfamily|superfamily|NN|O ,|,|,|O including|include|VBG|O TGF-betas|TGF-betas|NN|O and|and|CC|O bone-morphogenetic-proteins|bone-morphogenetic-protein|NNS|O (|(|(|O BMPs|bmp|NNS|O )|)|)|O ,|,|,|O are|be|VBP|O essential|essential|JJ|O for|for|IN|O the|the|DT|O maintenance|maintenance|NN|O of|of|IN|O tissue|tissue|NN|O homeostasis|homeostasis|NN|O and|and|CC|O regeneration|regeneration|NN|O after|after|IN|O injury|injury|NN|O .|.|.|O 
We|we|PRP|O have|have|VBP|O observed|observe|VBN|O that|that|IN|O the|the|DT|O BMP|BMP|NN|GENE antagonist|antagonist|NN|O ,|,|,|O gremlin|gremlin|NN|GENE ,|,|,|O is|be|VBZ|O highly|high|RB|O up-regulated|upregulate|VBN|O in|in|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O .|.|.|O 
OBJECTIVES|objective|NNS|O :|:|:|O To|to|TO|O investigate|investigate|VB|O the|the|DT|O role|role|NN|O of|of|IN|O gremlin|gremlin|NN|GENE in|in|IN|O the|the|DT|O regulation|regulation|NN|O of|of|IN|O BMP|BMP|NN|GENE signaling|signaling|NN|O in|in|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
METHODS|method|NNS|O :|:|:|O Progressive|progressive|JJ|O asbestos-induced|asbestos-induced|JJ|O fibrosis|fibrosis|NN|O in|in|IN|O the|the|DT|O mouse|mouse|NN|O was|be|VBD|O used|use|VBN|O as|as|IN|O a|a|DT|O model|model|NN|O of|of|IN|O human|human|JJ|O IPF|IPF|NN|O .|.|.|O 
TGF-beta|TGF-beta|NN|GENE and|and|CC|O BMP|BMP|NN|GENE expression|expression|NN|O and|and|CC|O signaling|signaling|NN|O activities|activity|NNS|O were|be|VBD|O measured|measure|VBN|O from|from|IN|O murine|murine|JJ|O and|and|CC|O human|human|JJ|O fibrotic|fibrotic|JJ|O lungs|lung|NNS|O .|.|.|O 
The|the|DT|O mechanism|mechanism|NN|O of|of|IN|O gremlin|gremlin|NN|GENE induction|induction|NN|O was|be|VBD|O analyzed|analyse|VBN|O in|in|IN|O cultured|culture|VBN|O lung|lung|NN|O epithelial|epithelial|JJ|O cells|cell|NNS|O .|.|.|O 
In|in|IN|O addition|addition|NN|O ,|,|,|O the|the|DT|O possible|possible|JJ|O therapeutic|therapeutic|JJ|O role|role|NN|O of|of|IN|O gremlin|gremlin|NN|GENE inhibition|inhibition|NN|O was|be|VBD|O tested|test|VBN|O by|by|IN|O administration|administration|NN|O of|of|IN|O BMP-7|BMP-7|NN|GENE to|to|TO|O mice|mouse|NNS|O after|after|IN|O asbestos|asbestos|NN|O exposure|exposure|NN|O .|.|.|O 
MEASUREMENTS|measurement|NNS|O AND|and|CC|O MAIN|main|NNS|O RESULTS|result|NNS|O :|:|:|O Gremlin|gremlin|NN|GENE mRNA|mRNA|NN|O levels|level|NNS|O were|be|VBD|O up-regulated|upregulate|VBN|O in|in|IN|O the|the|DT|O asbestos-exposed|asbestos-exposed|JJ|O mouse|mouse|NN|O lungs|lung|NNS|O ,|,|,|O which|which|WDT|O is|be|VBZ|O in|in|IN|O agreement|agreement|NN|O with|with|IN|O the|the|DT|O human|human|JJ|O IPF|IPF|NN|O biopsy|biopsy|NN|O data|datum|NNS|O .|.|.|O 
Down-regulation|Down-regulation|NN|O of|of|IN|O BMP|BMP|NN|GENE signaling|signaling|NN|O was|be|VBD|O demonstrated|demonstrate|VBN|O by|by|IN|O reduced|reduce|VBN|O levels|level|NNS|O of|of|IN|O Smad1/5/8|Smad1/5/8|NN|O and|and|CC|O enhanced|enhance|VBD|O Smad2|Smad2|NN|GENE phosphorylation|phosphorylation|NN|O in|in|IN|O asbestos-treated|asbestos-treated|JJ|O lungs|lung|NNS|O .|.|.|O 
Accordingly|according|RB|O ,|,|,|O analyses|analysis|NNS|O of|of|IN|O cultured|culture|VBN|O human|human|JJ|O bronchial|bronchial|JJ|O epithelial|epithelial|JJ|O cells|cell|NNS|O indicated|indicate|VBD|O that|that|IN|O asbestos-induced|asbestos-induced|JJ|O gremlin|gremlin|NN|GENE expression|expression|NN|O could|can|MD|O be|be|VB|O prevented|prevent|VBN|O by|by|IN|O inhibitors|inhibitor|NNS|O of|of|IN|O the|the|DT|O TGF-beta|TGF-beta|NN|GENE receptor|receptor|NN|O and|and|CC|O also|also|RB|O by|by|IN|O inhibitors|inhibitor|NNS|O of|of|IN|O the|the|DT|O mitogen-activated|mitogen-activated|JJ|O protein|protein|NN|O kinase|kinase|NN|O kinase/extracellular|kinase/extracellular|JJ|O signal-regulated|signal-regulated|JJ|O protein|protein|NN|O kinase|kinase|NN|O pathways|pathway|NNS|O .|.|.|O 
BMP-7|BMP-7|NN|GENE treatment|treatment|NN|O significantly|significant|RB|O reduced|reduce|VBD|O hydroxyproline|hydroxyproline|NN|O contents|content|NNS|O in|in|IN|O the|the|DT|O asbestos-treated|asbestos-treated|JJ|O mice|mouse|NNS|O .|.|.|O 
CONCLUSIONS|conclusion|NNS|O :|:|:|O The|the|DT|O TGF-beta|TGF-beta|NN|GENE and|and|CC|O BMP|BMP|NN|GENE signaling|signaling|NN|O balance|balance|NN|O is|be|VBZ|O important|important|JJ|O for|for|IN|O lung|lung|NN|O regenerative|regenerative|JJ|O events|event|NNS|O and|and|CC|O is|be|VBZ|O significantly|significant|RB|O perturbed|perturb|VBN|O in|in|IN|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Rescue|rescue|NN|O of|of|IN|O BMP|BMP|NN|GENE signaling|signaling|NN|O activity|activity|NN|O may|may|MD|O represent|represent|VB|O a|a|DT|O potential|potential|JJ|O beneficial|beneficial|JJ|O strategy|strategy|NN|O for|for|IN|O treating|treat|VBG|O human|human|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O .|.|.|O 
Transforming|Transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE induces|induce|VBZ|O epithelial-to-mesenchymal|epithelial-to-mesenchymal|JJ|O transition|transition|NN|O of|of|IN|O A549|A549|NN|O cells|cell|NNS|O .|.|.|O 
Idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O comprises|comprise|VBZ|O an|a|DT|O aggregate|aggregate|NN|O of|of|IN|O mesenchymal|mesenchymal|JJ|O cells|cell|NNS|O .|.|.|O 
However|however|RB|O ,|,|,|O the|the|DT|O cellular|cellular|JJ|O origin|origin|NN|O of|of|IN|O these|these|DT|O mesenchymal|mesenchymal|JJ|O phenotypes|phenotype|NNS|O remains|remain|VBZ|O unclear|unclear|JJ|O .|.|.|O 
Transforming|Transforming|NN|GENE growth|growth|NN|GENE factor|factor|NN|GENE beta1|beta1|NN|GENE (|(|(|O TGF-beta1|TGF-beta1|NN|GENE )|)|)|O has|have|VBZ|O been|be|VBN|O known|know|VBN|O as|as|IN|O the|the|DT|O main|main|JJ|O cytokine|cytokine|NN|O involved|involve|VBN|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
We|we|PRP|O examined|examine|VBD|O whether|whether|IN|O the|the|DT|O potent|potent|JJ|O fibrogenic|fibrogenic|JJ|O cytokine|cytokine|NN|O TGF-beta1|TGF-beta1|NN|GENE could|can|MD|O induce|induce|VB|O the|the|DT|O epithelial-to-mesenchymal|epithelial-to-mesenchymal|JJ|O transition|transition|NN|O (|(|(|O EMT|emt|NN|GENE )|)|)|O in|in|IN|O the|the|DT|O human|human|JJ|O alveolar|alveolar|JJ|O epithelial|epithelial|JJ|O cell|cell|NN|O line|line|NN|O ,|,|,|O A549|A549|NN|O ,|,|,|O and|and|CC|O determined|determine|VBD|O whether|whether|IN|O snail|snail|NN|O expression|expression|NN|O is|be|VBZ|O associated|associate|VBN|O with|with|IN|O the|the|DT|O phenotypic|phenotypic|JJ|O changes|change|NNS|O observed|observe|VBN|O in|in|IN|O the|the|DT|O A549|A549|NN|O cells|cell|NNS|O .|.|.|O 
EMT|emt|NN|GENE was|be|VBD|O investigated|investigate|VBN|O with|with|IN|O cells|cell|NNS|O morphology|morphology|NN|O changes|change|NNS|O under|under|IN|O phase-contrast|phase-contrast|JJ|O microscopy|microscopy|NN|O ,|,|,|O western|western|NN|O blotting|blotting|NN|O ,|,|,|O and|and|CC|O indirect|indirect|JJ|O immunofluorescence|immunofluorescence|NN|O stains|stain|NNS|O .|.|.|O 
E-cadherin|e-cadherin|NN|GENE and|and|CC|O transcription|transcription|NN|O factor|factor|NN|O ,|,|,|O snail|snail|NN|O ,|,|,|O were|be|VBD|O also|also|RB|O evaluated|evaluate|VBN|O by|by|IN|O measuring|measure|VBG|O mRNA|mRNA|NN|O levels|level|NNS|O using|use|VBG|O reverse|reverse|JJ|O transcriptase-polymerase|transcriptase-polymerase|NN|O chain|chain|NN|O reaction|reaction|NN|O (|(|(|O RT-PCR|rt-pcr|NN|O )|)|)|O analysis|analysis|NN|O .|.|.|O 
The|the|DT|O data|datum|NNS|O showed|show|VBD|O that|that|IN|O TGF-beta1|TGF-beta1|NN|GENE induced|induce|VBD|O A549|A549|NN|O cells|cell|NNS|O with|with|IN|O epithelial|epithelial|JJ|O cell|cell|NN|O characteristics|characteristic|NNS|O to|to|TO|O undergo|undergo|VB|O EMT|emt|NN|GENE in|in|IN|O a|a|DT|O concentration-dependent|concentration-dependent|JJ|O manner|manner|NN|O .|.|.|O 
Following|follow|VBG|O TGF-beta1|TGF-beta1|NN|GENE treatment|treatment|NN|O ,|,|,|O A549|A549|NN|O cells|cell|NNS|O induced|induce|VBD|O EMT|emt|NN|GENE characterized|characterize|VBN|O by|by|IN|O cells|cell|NNS|O morphological|morphological|JJ|O changes|change|NNS|O ,|,|,|O loss|loss|NN|O of|of|IN|O epithelial|epithelial|JJ|O markers|marker|NNS|O Ecaherin|Ecaherin|NNP|O and|and|CC|O cytokeratin|cytokeratin|NN|O ,|,|,|O increased|increase|VBD|O stress|stress|NN|O fiber|fiber|NN|O reorganization|reorganization|NN|O by|by|IN|O F-actin|F-actin|NN|O ,|,|,|O and|and|CC|O cytokeratin|cytokeratin|NN|O replacement|replacement|NN|O by|by|IN|O vimentin|vimentin|NN|GENE .|.|.|O 
Although|although|IN|O IL-1beta|IL-1beta|NN|GENE failed|fail|VBD|O to|to|TO|O induce|induce|VB|O A549|A549|NN|O cells|cell|NNS|O to|to|TO|O undergo|undergo|VB|O EMT|emt|NN|GENE ,|,|,|O the|the|DT|O combination|combination|NN|O of|of|IN|O TGF-beta1|TGF-beta1|NN|GENE and|and|CC|O IL-1beta|IL-1beta|NN|GENE showed|show|VBD|O synergy|synergy|NN|O effects|effect|NNS|O in|in|IN|O cells|cell|NNS|O morphology|morphology|NN|O changes|change|NNS|O and|and|CC|O the|the|DT|O expression|expression|NN|O of|of|IN|O mesenchymal|mesenchymal|JJ|O markers|marker|NNS|O .|.|.|O 
The|the|DT|O snail|snail|NN|O expression|expression|NN|O study|study|NN|O using|use|VBG|O RT-PCR|rt-pcr|NN|O analysis|analysis|NN|O provided|provide|VBD|O that|that|IN|O loss|loss|NN|O of|of|IN|O E-cadherin|e-cadherin|NN|GENE expression|expression|NN|O was|be|VBD|O associated|associate|VBN|O with|with|IN|O snail|snail|NN|O expression|expression|NN|O .|.|.|O 
Stimulation|stimulation|NN|O of|of|IN|O A54|A54|NN|O cells|cell|NNS|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE plus|plus|CC|O IL-1beta|IL-1beta|NN|GENE revealed|reveal|VBD|O a|a|DT|O higher|high|JJR|O level|level|NN|O of|of|IN|O snail|snail|NN|O expression|expression|NN|O .|.|.|O 
Our|our|PRP$|O data|datum|NNS|O showed|show|VBD|O that|that|IN|O EMT|emt|NN|GENE of|of|IN|O A549|A549|NN|O cells|cell|NNS|O might|may|MD|O be|be|VB|O closely|close|RB|O associated|associate|VBN|O with|with|IN|O snail|snail|NN|O expression|expression|NN|O .|.|.|O 
Pirfenidone|Pirfenidone|NN|O inhibits|inhibit|VBZ|O the|the|DT|O expression|expression|NN|O of|of|IN|O HSP47|HSP47|NN|GENE in|in|IN|O TGF-beta1-stimulated|tgf-beta1-stimulated|JJ|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O .|.|.|O 
Pirfenidone|Pirfenidone|NN|O (|(|(|O 5-methyl-1-phenyl-2|5-methyl-1-phenyl-2|NN|O -|-|:|O (|(|(|O 1H|1H|NN|O )|)|)|O -|-|:|O pyridone|pyridone|NN|O )|)|)|O is|be|VBZ|O a|a|DT|O novel|novel|JJ|O anti-fibrotic|anti-fibrotic|JJ|O and|and|CC|O anti-inflammatory|anti-inflammatory|JJ|O agent|agent|NN|O that|that|WDT|O inhibits|inhibit|VBZ|O the|the|DT|O progression|progression|NN|O of|of|IN|O fibrosis|fibrosis|NN|O in|in|IN|O animal|animal|NN|O models|model|NNS|O and|and|CC|O patients|patient|NNS|O with|with|IN|O idiopathic|idiopathic|JJ|O pulmonary|pulmonary|JJ|O fibrosis|fibrosis|NN|O (|(|(|O IPF|IPF|NN|O )|)|)|O .|.|.|O 
Heat|heat|NN|O shock|shock|NN|O protein|protein|NN|O (|(|(|O HSP|Hsp|NN|O )|)|)|O 47|47|CD|O ,|,|,|O a|a|DT|O collagen-specific|collagen-specific|JJ|O molecular|molecular|JJ|O chaperone|chaperone|NN|O ,|,|,|O is|be|VBZ|O involved|involve|VBN|O in|in|IN|O the|the|DT|O processing|processing|NN|O and/or|and/or|CC|O secretion|secretion|NN|O of|of|IN|O procollagen|procollagen|NN|O and|and|CC|O plays|play|VBZ|O an|a|DT|O important|important|JJ|O role|role|NN|O in|in|IN|O the|the|DT|O pathogenesis|pathogenesis|NN|O of|of|IN|O IPF|IPF|NN|O .|.|.|O 
The|the|DT|O present|present|JJ|O study|study|NN|O evaluated|evaluate|VBD|O the|the|DT|O in|in|FW|O vitro|vitro|FW|O effects|effect|NNS|O of|of|IN|O pirfenidone|pirfenidone|NN|O on|on|IN|O expression|expression|NN|O of|of|IN|O HSP47|HSP47|NN|GENE and|and|CC|O collagen|collagen|NN|O type|type|NN|O I|i|CD|O in|in|IN|O cultured|culture|VBN|O normal|normal|JJ|O human|human|JJ|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O (|(|(|O NHLF|NHLF|NN|O )|)|)|O .|.|.|O 
Expression|expression|NN|O levels|level|NNS|O of|of|IN|O HSP47|HSP47|NN|GENE and|and|CC|O collagen|collagen|NN|O type|type|NN|O I|i|CD|O in|in|IN|O NHLF|NHLF|NN|O stimulated|stimulate|VBN|O by|by|IN|O transforming|transform|VBG|O growth|growth|NN|O factor|factor|NN|O (|(|(|O TGF|tgf|NN|O )|)|)|O -|-|:|O beta1|beta1|NN|O were|be|VBD|O evaluated|evaluate|VBN|O genetically|genetic|RB|O ,|,|,|O immunologically|immunological|RB|O and|and|CC|O immunocytochemically|immunocytochemical|RB|O .|.|.|O 
Treatment|treatment|NN|O with|with|IN|O TGF-beta1|TGF-beta1|NN|GENE stimulated|stimulate|VBD|O both|both|CC|O mRNA|mRNA|NN|O and|and|CC|O protein|protein|NN|O expressions|expression|NNS|O of|of|IN|O both|both|DT|O HSP47|HSP47|NN|GENE and|and|CC|O collagen|collagen|NN|O type|type|NN|O I|i|CD|O in|in|IN|O NHLF|NHLF|NN|O ,|,|,|O and|and|CC|O pirfenidone|pirfenidone|NN|O significantly|significant|RB|O inhibited|inhibit|VBD|O this|this|DT|O TGF-beta1-enhanced|tgf-beta1-enhanced|JJ|O expression|expression|NN|O in|in|IN|O a|a|DT|O dose-dependent|dose-dependent|JJ|O manner|manner|NN|O .|.|.|O 
We|we|PRP|O concluded|conclude|VBD|O that|that|IN|O the|the|DT|O anti-fibrotic|anti-fibrotic|JJ|O effect|effect|NN|O of|of|IN|O pirfenidone|pirfenidone|NN|O may|may|MD|O be|be|VB|O mediated|mediate|VBN|O not|not|RB|O only|only|RB|O through|through|IN|O direct|direct|JJ|O inhibition|inhibition|NN|O of|of|IN|O collagen|collagen|NN|O type|type|NN|O I|i|CD|O expression|expression|NN|O but|but|CC|O also|also|RB|O at|at|IN|O least|little|JJS|O partly|partly|RB|O through|through|IN|O inhibition|inhibition|NN|O of|of|IN|O HSP47|HSP47|NN|GENE expression|expression|NN|O in|in|IN|O lung|lung|NN|O fibroblasts|fibroblast|NNS|O ,|,|,|O with|with|IN|O a|a|DT|O resultant|resultant|JJ|O reduction|reduction|NN|O of|of|IN|O collagen|collagen|NN|O synthesis|synthesis|NN|O in|in|IN|O lung|lung|NN|O fibrosis|fibrosis|NN|O .|.|.|O