MMP13 and osteoarthritis: Studies have shown that CDR1as 49, circ-0005105 50, circ-33186 51, circ-0136474 52, circ-100226 32, circ-CER 53, circ-PSM3 54, circ-Atp9b 55, circ-UBE2G1 56, circ-0092516 57, circ-CDH13 58, circ-TMBIM6 59, circ-RNF121 60, circ-VCAN 61, and circ-HIPK3 62, which were found over-expressed in cartilage of osteoarthritis, could significantly promote the expression of osteoarthritis-related genes including MMP13, PTEN, FGF2, NAMPT, TNFα, TLR4, HIFα, MYD88, and SOX8, thereby accelerating the progress osteoarthritis.