EZH2 and hepatocellular carcinoma: Sun et al.95 found that circ-ADD3 enhanced the interaction between cyclin-dependent kinase 1 (CDK1) and histone-lysine N-methyltransferase (EZH2), resulting in ubiquitination and degradation of EZH2 through phosphorylation at Thr-345 and Thr-487 during the progression of HCC.