MMP2 and rheumatoid arthritis: To verify our hypothesis, luciferase reporter assays confirmed the direct interaction between Circ_0088194 and miR-766-3p, and between miR-766-3p and MMP2. Importantly, miR-766-3p reverses the ability of Circ_0088194 to upregulate MMP2 expression and promote RA-FLS migration and invasion.