Fascin1 mediated release of pro-inflammatory cytokines and invasion/migration in rheumatoid arthritis via the STAT3 pathway.

Rheumatoid arthritis (RA) is a chronic, multi-factorial disease characterized by Synovial hyperplasia, chronic inflammation, and autoimmune reaction. Fascin1 overexpression has been implicated in cancer, immune, and inflammatory diseases. However, the relationship between Fascin1 and rheumatoid arthritis (RA) has not yet been determined. We investigated whether Fascin1 could modulate pro-inflammatory cytokine secretion and the proliferation, apoptosis, and invasion/migration of fibroblast-like synoviocytes (RA-FLSs). Fascin 1 was suppressed with a short interfering (si)RNA approach. Functional analysis contained MTT assay, flow cytometry,Transwell™ assays, wound healing, Quantitative polymerase chain reaction and western blotting were used to detect cell proliferation,apoptosis ratio, invasion/ migration, the mRNA and protein expression of the realted markers, respectively. Overexpression of fascin1 was observed in RA-FLSs group compared with control group. Fascin1 expression positively correlated with changes in the expression of RA disease activity markers (RF, CRP, and DAB28, respectively). We also observed a significant positive correlation between Fascin1 and STAT3 mRNA levels in RA- FLSs.Fascin1 silencing attenuated the expression of pro-inflammatory cytokines; reduced FLS proliferation in vitro; and increased apoptosis ratio and bax, cleaved PARP, and caspase-3 expression. si- Fascin1 transfection delayed RA-FLS invasion/migration and reversed the epithelial- mesenchymal transition. These data suggest that Fascin1 exerts positive effects on the proliferation, cell cycle, and invasion/migration of RA-FLSs by activating signal transducer and activator of transcription 3 signaling.After all, Fascin1 contributed to RA development.