title: TWEAK enhances TGF-β-induced epithelial-mesenchymal transition in human bronchial epithelial cells.
abstract: BACKGROUND
  Chronic airway inflammatory disorders, such as asthma, are characterized by airway inflammation and remodeling. Chronic inflammation and damage to the airway epithelium cause airway remodeling, which is associated with improper epithelial repair, and is characterized by elevated expression of transforming growth factor-β (TGF-β). Epithelial-mesenchymal transition (EMT) is an important mechanism during embryonic development and tissue remodeling whereby epithelial cells gain the capacity to increase motility by down-regulation of epithelial markers and up-regulation of mesenchymal markers. TGF-β is a central inducer of EMT, and TGF-β-induced EMT is enhanced by pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-1β. We investigated whether the pro-inflammatory cytokine TWEAK (TNF-like weak inducer of apoptosis) enhanced TGF-β1-induced EMT in the human bronchial epithelial cell line BEAS-2B.
  
  
  METHODS
  Quantitative RT-PCR and western blotting were used to define alterations in epithelial and mesenchymal marker expression in BEAS-2B cells. The cells were assessed for 48 h after stimulation with TGF-β1 alone or in combination with TWEAK.
  
  
  RESULTS
  TGF-β1 induced spindle-like morphology and loss of cell contact, and reduced the expression of epithelial marker E-cadherin and increased the expression of mesenchymal markers N-cadherin and vimentin. Our data, for the first time, show that TWEAK reduced the expression of E-cadherin, and that co-treatment with TGF-β1 and TWEAK enhanced the TGF-β1-induced features of EMT. Moreover, hyaluronan synthase 2 expression was up-regulated by a combination with TGF-β1 and TWEAK, but not TNF-α. We also demonstrated that the Smad, p38 MAPK, and NF-κB signaling pathways, and the transcriptional repressor ZEB2 might mediate N-cadherin up-regulation by TGF-β1 in combination with TWEAK.
  
  
  CONCLUSIONS
  These findings suggest that the pro-inflammatory cytokine TWEAK and TGF-β1 have synergistic effects in EMT and may contribute to chronic airway changes and remodeling.
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. yuitoiga@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. yuitoiga@juntendo.ac.jp.
authors.forename: Yukinari
authors.initials: Y
authors.lastname: Itoigawa
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. nor@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. nor@juntendo.ac.jp.|Atopy (Allergy) Research Center, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. nor@juntendo.ac.jp.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Harada
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. snharada@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. snharada@juntendo.ac.jp.
authors.forename: Sonoko
authors.initials: S
authors.lastname: Harada
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. ykatura@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. ykatura@juntendo.ac.jp.|Atopy (Allergy) Research Center, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. ykatura@juntendo.ac.jp.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Katsura
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. makino@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. makino@juntendo.ac.jp.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Makino
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. moisture@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. moisture@juntendo.ac.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Ito
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. fariz@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. fariz@juntendo.ac.jp.
authors.forename: Fariz
authors.initials: F
authors.lastname: Nurwidya
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. mtkatou@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. mtkatou@juntendo.ac.jp.
authors.forename: Motoyasu
authors.initials: M
authors.lastname: Kato
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. fumiyuki@dol.hi-ho.ne.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. fumiyuki@dol.hi-ho.ne.jp.
authors.forename: Fumiyuki
authors.initials: F
authors.lastname: Takahashi
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. atsuta@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. atsuta@juntendo.ac.jp.
authors.forename: Ryo
authors.initials: R
authors.lastname: Atsuta
authors.affiliation: Department of Respiratory Medicine, Juntendo University Faculty of Medicine and Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo, 113-8431, Japan. kztakaha@juntendo.ac.jp.|Research Institute for Diseases of Old Ages, Juntendo University Faculty of Medicine and Graduate School of Medicine, Tokyo, Japan. kztakaha@juntendo.ac.jp.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D056151:Airway Remodeling / Q000187:drug effects; D015703:Antigens, CD / Q000378:metabolism; D001980:Bronchi / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D015820:Cadherins / Q000378:metabolism; D002461:Cell Line, Transformed; D048430:Cell Shape / Q000187:drug effects; D000074049:Cytokine TWEAK; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects*; D005786:Gene Expression Regulation; D014453:Glucuronosyltransferase / Q000378:metabolism; D006801:Humans; D000076002:Hyaluronan Synthases; D016328:NF-kappa B / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D051785:Smad Proteins / Q000378:metabolism; D013997:Time Factors; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*; D048069:Tumor Necrosis Factors / Q000494:pharmacology*; D014746:Vimentin / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D015703:Antigens, CD; C513384:CDH1 protein, human; C050361:CDH2 protein, human; D015820:Cadherins; D000074049:Cytokine TWEAK; D016328:NF-kappa B; D011994:Recombinant Proteins; D051785:Smad Proteins; C508960:TGFB1 protein, human; C109743:TNFSF12 protein, human; D053773:Transforming Growth Factor beta1; D048069:Tumor Necrosis Factors; D014746:Vimentin; D014453:Glucuronosyltransferase; C101754:HAS2 protein, human; D000076002:Hyaluronan Synthases; D048051:p38 Mitogen-Activated Protein Kinases