C-S Wu1, P-H Wu, A-H Fang, C-C E Lan. 1. Department of Medical Laboratory Science and Biotechnology, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan.
Abstract
BACKGROUND: Keloid is a unique proliferative disorder of fibroblasts resulting from derailment of the typical wound healing process. Due to lack of animal models for therapeutic testing, treatment of keloids remains a clinical challenge. Transforming growth factor (TGF)-β1-related signalling plays a key role in keloid formation. As tacrolimus (FK506) has been reported to inhibit the effects of TGF-β1 on cultured fibroblasts, we hypothesized that FK506 may be useful in treating keloids. OBJECTIVES: To explore the effects of FK506 on TGF-β1-stimulated keloid fibroblasts (KFs) in terms of proliferation, migration and collagen production and to investigate the regulatory pathways involved. METHODS: Fibroblasts derived from keloids were treated with TGF-β1 with or without FK506. Relevant assays including 5-bromo-2'-deoxyuridine incorporation assay, in vitro scratch assay, reverse transcription-polymerase chain reaction (PCR), quantitative PCR and Western blotting were performed. RESULTS: The proliferation and migration of KFs were significantly higher than those of normal fibroblasts. FK506 markedly inhibited KF proliferation, migration and collagen production enhanced by TGF-β1. The increase in TGF-β receptor I and II expression in TGF-β1-treated KFs was suppressed by FK506 treatment. TGF-β1 increased the phosphorylation of Smad2/3 and Smad4 in KFs, and this enhancing effect was abrogated by FK506. In addition, FK506 significantly increased the expression of Smad7 which was suppressed by TGF-β1 treatment. CONCLUSIONS: Our results demonstrate that FK506 effectively blocks the TGF-β/Smad signalling pathway in KFs by downregulation of TGF-β receptors and suggest that FK506 may be included in the armamentarium for treating keloids.
BACKGROUND: Keloid is a unique proliferative disorder of fibroblasts resulting from derailment of the typical wound healing process. Due to lack of animal models for therapeutic testing, treatment of keloids remains a clinical challenge. Transforming growth factor (TGF)-β1-related signalling plays a key role in keloid formation. As tacrolimus (FK506) has been reported to inhibit the effects of TGF-β1 on cultured fibroblasts, we hypothesized that FK506 may be useful in treating keloids. OBJECTIVES: To explore the effects of FK506 on TGF-β1-stimulated keloid fibroblasts (KFs) in terms of proliferation, migration and collagen production and to investigate the regulatory pathways involved. METHODS: Fibroblasts derived from keloids were treated with TGF-β1 with or without FK506. Relevant assays including 5-bromo-2'-deoxyuridine incorporation assay, in vitro scratch assay, reverse transcription-polymerase chain reaction (PCR), quantitative PCR and Western blotting were performed. RESULTS: The proliferation and migration of KFs were significantly higher than those of normal fibroblasts. FK506 markedly inhibited KF proliferation, migration and collagen production enhanced by TGF-β1. The increase in TGF-β receptor I and II expression in TGF-β1-treated KFs was suppressed by FK506 treatment. TGF-β1 increased the phosphorylation of Smad2/3 and Smad4 in KFs, and this enhancing effect was abrogated by FK506. In addition, FK506 significantly increased the expression of Smad7 which was suppressed by TGF-β1 treatment. CONCLUSIONS: Our results demonstrate that FK506 effectively blocks the TGF-β/Smad signalling pathway in KFs by downregulation of TGF-β receptors and suggest that FK506 may be included in the armamentarium for treating keloids.
Authors: Claudia A Staab-Weijnitz; Isis E Fernandez; Larissa Knüppel; Julia Maul; Katharina Heinzelmann; Brenda M Juan-Guardela; Elisabeth Hennen; Gerhard Preissler; Hauke Winter; Claus Neurohr; Rudolf Hatz; Michael Lindner; Jürgen Behr; Naftali Kaminski; Oliver Eickelberg Journal: Am J Respir Crit Care Med Date: 2015-08-15 Impact factor: 21.405
Authors: Jason C Gardenier; Raghu P Kataru; Geoffrey E Hespe; Ira L Savetsky; Jeremy S Torrisi; Gabriela D García Nores; Dawit K Jowhar; Matthew D Nitti; Ryan C Schofield; Dean C Carlow; Babak J Mehrara Journal: Nat Commun Date: 2017-02-10 Impact factor: 14.919