title: Gene expression profiling reveals novel TGFbeta targets in adult lung fibroblasts.
abstract: BACKGROUND
  Transforming growth factor beta (TGFbeta), a multifunctional cytokine, plays a crucial role in the accumulation of extracellular matrix components in lung fibrosis, where lung fibroblasts are considered to play a major role. Even though the effects of TGFbeta on the gene expression of several proteins have been investigated in several lung fibroblast cell lines, the global pattern of response to this cytokine in adult lung fibroblasts is still unknown.
  
  
  METHODS
  We used Affymetrix oligonucleotide microarrays U95v2, containing approximately 12,000 human genes, to study the transcriptional profile in response to a four hour treatment with TGFbeta in control lung fibroblasts and in fibroblasts from patients with idiopathic and scleroderma-associated pulmonary fibrosis. A combination of the Affymetrix change algorithm (Microarray Suite 5) and of analysis of variance models was used to identify TGFbeta-regulated genes. Additional criteria were an average up- or down- regulation of at least two fold.
  
  
  RESULTS
  Exposure of fibroblasts to TGFbeta had a profound impact on gene expression, resulting in regulation of 129 transcripts. We focused on genes not previously found to be regulated by TGFbeta in lung fibroblasts or other cell types, including nuclear co-repressor 2, SMAD specific E3 ubiquitin protein ligase 2 (SMURF2), bone morphogenetic protein 4, and angiotensin II receptor type 1 (AGTR1), and confirmed the microarray results by real time-PCR. Western Blotting confirmed induction at the protein level of AGTR1, the most highly induced gene in both control and fibrotic lung fibroblasts among genes encoding for signal transduction molecules. Upregulation of AGTR1 occurred through the MKK1/MKK2 signalling pathway. Immunohistochemical staining showed AGTR1 expression by lung fibroblasts in fibroblastic foci within biopsies of idiopathic pulmonary fibrosis.
  
  
  CONCLUSIONS
  This study identifies several novel TGFbeta targets in lung fibroblasts, and confirms with independent methods the induction of angiotensin II receptor type 1, underlining a potential role for angiotensin II receptor 1 antagonism in the treatment of lung fibrosis.
authors.affiliation: Interstitial Lung Disease Unit, Royal Brompton Hospital, Imperial College of Science, Technology and Medicine, Emmanuel Kaye Building, 1B Manresa Road, SW3 6LR, London, UK. e.renzoni@imperial.ac.uk <e.renzoni@imperial.ac.uk>
authors.forename: Elisabetta A
authors.initials: EA
authors.lastname: Renzoni
authors.forename: David J
authors.initials: DJ
authors.lastname: Abraham
authors.forename: Sarah
authors.initials: S
authors.lastname: Howat
authors.forename: Xu
authors.initials: X
authors.lastname: Shi-Wen
authors.forename: Piersante
authors.initials: P
authors.lastname: Sestini
authors.forename: George
authors.initials: G
authors.lastname: Bou-Gharios
authors.forename: Athol U
authors.initials: AU
authors.lastname: Wells
authors.forename: Srihari
authors.initials: S
authors.lastname: Veeraraghavan
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Nicholson
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Denton
authors.forename: Andrew
authors.initials: A
authors.lastname: Leask
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Pearson
authors.forename: Carol M
authors.initials: CM
authors.lastname: Black
authors.forename: Kenneth I
authors.initials: KI
authors.lastname: Welsh
authors.forename: Roland M
authors.initials: RM
authors.lastname: du Bois
mesh_terms: D002478:Cells, Cultured; D016503:Drug Delivery Systems; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism*; D020869:Gene Expression Profiling; D006801:Humans; D011658:Pulmonary Fibrosis / Q000378:metabolism*; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
chemical_list: D044140:Receptor, Angiotensin, Type 1; D016212:Transforming Growth Factor beta