Circ_0000423/miRNA-27b-3p/MMP-13 axis regulates cartilage ECM synthesis in osteoarthritis [18], and exosome-transported circRNA_0001236 enhances chondrogenesis and inhibits cartilage degeneration via miR-3677-3p/Sox9 axis [19]. Here, SOX9 is linked to osteoarthritis.