Title:Targeting FGFR3 is a Useful Therapeutic Strategy for Rheumatoid Arthritis
Treatment
Volume: 17
Author(s): Shan-Fu Yu, Tien-Tsai Cheng, Gong-Kai Huang, Chung-Yuan Hsu, Ying-Hsien Kao*Yueh-Hua Chung
Affiliation:
- Department of Medical Research, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
Keywords:
Epithelial-mesenchymal transition, FGFR3, Inflammation, Rheumatoid arthritis, Synoviocytes, TNF-α.
Abstract:
Background:
Rheumatoid arthritis (RA) is a systemic inflammatory disease in which TNF-α plays an important role. Fibroblast growth factor receptor 3
(FGFR3) is reportedly involved in RA by regulating the expression of inflammatory cytokines.
Objective:
This study examined the expression profile of FGFR3 in human synovial biopsy tissues and evaluated its gene-silencing effects on behaviors of
synovial cells.
Methods:
Immunohistochemical staining was used to measure FGFR3 expression in human RA joint tissues. Cell proliferation, migration, and apoptosis
assays were used to monitor behavioral changes in cultured synovial SW-982 cells with siRNA-mediated FGFR3 gene silencing.
Immunofluorescent staining and western blotting were used to detect molecular changes in the FGFR3 gene-silenced cells.
Results:
FGFR3 up-regulation was noted in both cytoplasms and nuclei of synovial cells in human RA joints. FGFR3 siRNA delivery experiments
corroborated that FGFR3 knockdown decreased proliferation and migration, and triggered apoptosis of synovial cells. The FGFR3 gene
knockdown enhanced constitutive expression of epithelial marker E-cadherin and conversely suppressed expression of epithelial-mesenchymal
transition (EMT) markers, including Snail, fibronectin, and vimentin. In addition, FGFR3 silencing significantly reduced the constitutive
expressions of TNF-α, transcription factor NF-κΒ, and downstream COX-2 protein and collagenolytic enzyme MMP-9. MAPK inhibition
markedly suppressed constitutive levels of NF-κΒ, COX-2, and MMP-9.
Conclusion:
Genetic interference of FGFR3 could modulate the expression of inflammatory mediators and EMT markers in the synovial cells. Targeting the
FGFR3/MAPK signal axis may be considered a useful therapeutic strategy to ameliorate the development of RA.