A summary diagram of circRNAs in regulating osteoarthritis. (A) CircRNAs CDR1as, circ-0005105, circ-33186, circ-0136474, circ-100226, circ-CER, circ-PSM3, circ-Atp9b, circ-UBE2G1, circ-0092516, circ-CDH13, circ-TMBIM6, circ-RNF121, circ-VCAN, and circ-HIPK3 could significantly promote the progress of osteoarthritis by stimulating ECM catabolism, apoptosis, inflammation, but suppressing cell proliferation and ECM anabolism of chondrocytes thereby aggravating the progress of osteoarthritis. While circ-SERPINE2, circ-CDK14, circ-ANKRD36, circ-PDE4D, circ-0045714, and circ-9119 could inhibit the progress of osteogenesis by stimulating cell proliferation, ECM anabolism, but suppressing ECM catabolism, apoptosis, inflammation of chondrocytes thereby hindering the progress of osteoarthritis. (B) CircGCN1L1 could promote synoviocyte proliferation and chondrocyte apoptosis in osteoarthritis thereby aggravating the progress of osteoarthritis.