Abstract:

Objective To investigate the effect of circ_0005276 targeted miR⁃557 on the proliferation， migration and invasion of rheumatoid arthritis synovial fibroblasts（RA⁃FLS）. Methods RT⁃qPCR was used to detect the expression of circ_0005276 and miR⁃557 in synovium of CIA rats. Si⁃circ_0005276，si⁃NC，pcDNA， pcDNA⁃circ_0005276，miR⁃NC，miR⁃557 mimic，si⁃circ_0005276+anti⁃miR⁃NC and si⁃circ_0005276+anti⁃miR⁃ 557 were transfected into RA⁃FLS，CCK⁃8，scratch healing and Transwell assay to detect the activity，scratch heal⁃ ing rate and invasion number of RA⁃FLS. Double luciferase report verified the targeting relationship between circ_ 0005276 and miR⁃557. Results Compared with the normal synovial tissue，the expression of circ_0005276 in synovial tissue of CIA rats was up⁃regulated（P < 0.05）and the expression of miR⁃557 was down⁃regulated（P < 0.05）. After interfering with circ_0005276，the optical density（OD），scratch healing rate and invasion number of RA⁃ FLS decreased significantly（P < 0.05），while the expression of miR⁃557 increased（P < 0.05）. The expression of miR⁃557 in RA⁃FLS was significantly decreased after overexpression of circ_0005276（P < 0.05）. The OD value， scratch healing rate and invasion number of RA ⁃FLS decreased significantly after overexpression of miR ⁃ 557 （P < 0.05）. Down⁃regulation of miR⁃557 expression significantly weakened the effect of interfering circ_0005276 expression on the OD value，scratch healing rate and invasion number of RA⁃FLS（P < 0.05）. Conclusion Inter⁃ ference with circ_0005276 could promote the expression of miR⁃557 by targeting，thus inhibit the proliferation，mi⁃ gration，and invasion of RA⁃FLS. 

Key words:

rheumatoid arthritis, synovial fibroblasts, circ_0005276, miR ? 557, proliferation, migration, invasion