USP34 and osteoarthritis: Interestingly, USP34 is required for osteogenic differentiation and bone formation (Guo et al., 2018), BMP2 encodes bone morphogenetic protein 2 and regulates osteoinduction both in vitro and in vivo (Wang D. et al., 2019; Teng et al., 2019), CDH5 in acetabular labrum cells may be involved in the pathogenesis of osteoarthritis (Wang S. et al., 2019), and up-regulation of STC1 expression is associated with the occurrence of osteoarthritis in humans (Wu et al., 2019).