The expression and the function of miR-155 on rheumatoid arthritis synovial fibroblasts / 中华风湿病学杂志

ABSTRACT

Objective To screen for the miR-155 expression in synovial fibroblasts of rheumatoid arthritis (RASFs) and osteoarthritis (OASFs) and to evaluate the function of miR-155 on RASFs and its possible target mRNAs. Methods The expression levels of miR-155 in RASFs and OASFs were detected by real-time PCR. MiR-155 mimic and miR-155 inhibitor, as well as scrambled control were transfected into cultured RASFs by Lipofectamine 2000. Forty-eight hours later, MMP-3 levels in the cell culture supernatant were detected by ELISA and fibroblast proliferation was assayed by 3H -TdR incorporation test. Fibroblast invasive ability was tested by transwell system. IKBKE which previously identified as actual target of miR-155 was examined by real-time PCR. Comparisons between groups were performed with t test or one-way ANOVA analysis. Results It was shown that miR-155 was up-regulated in RASFs (1.79 ±1.94) and it was higher than that in OASFst (0.11±0.17), P<0.05]. Up-regulation of miR-155 could decrease MMP-3 levels (P<0.05). The proliferation and invasion of RASFs transfected with miR-155 were both evidently suppressed (P<0.05), while reducing the endogenous miR-155 could significantly enhance RASF proliferation (P<0.05). The expression of IKBKE of RASFs transfected with miR-155 was obviously down-regulated compared to those transfected with the scrambled control (P<0.05). Conclusion miR-155 is up-regulated in RASFs which may be a protective factor against the inflammatory effect, at least partially by attenuating the expression of IKBKK.