Background Hyperproliferative and invasion are the characteristics of fibroblast-like synoviocytes in rheumatoid arthritis (RA-FLSs), which contribute mainly to RA disease progression and ultimately to joint destruction. Endo180 is a recycling endocytic receptor that has functions to regulate cell migration and bind and internalize collagens. However, the expression of Endo180 in RA-FLSs and its underlying mechanisms remain unclear.
Objectives To examine the expression of Endo180 in RA-FLSs and the role it played in RA.
Methods Tissues were collected from RA patients with joint replacement surgery or arthroscopy and RA-FLSs were obtained by tissue culture; Westren blot was used to measure the expression of Endo180 in RA-FLSs. Chemically synthesized small interference RNA (siRNA) specifically targeting Endo180 gene was transfected into RA-FLSs by cationic liposome; The interference efficiency of Endo180-siRNA on the production of Endo180 mRNA and protein was determined by RT-qPCR and Western blot respectly; The proliferative inhibition rate was examined by CCK8 assay and the migration of RA-FLSs were examined by Transwell assay.
Results Expression of Endo180 was obviously higher in fibroblast-like synoviocytes in RA than OA and the traumatic patients. And its expression level has positive correlation with disease activity. The proliferative inhibition rate was obviously higher in the Endo180-siRNA group than the control groups (P<0.05) after transfection for 48h (8.31%±1.17%), 72h (15.93%±2.12)%), 96h (18.01%±2.78%). Transwell migration assay demonstrated the RA-FLSs through the transwell membrane in Endo180-siRNA group (21.27±6.35) were lesser than the NC-siRNA group (80.20±11.12) (P<0.05)and the blank control group (82.17±10.36) (P<0.05).
Conclusions Endo180 may play a role in the regulation of proliferation and migration of RA-FLSs, which may provide beneficial therapeutic effects in RA.
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Disclosure of Interest None declared