PCNA and hepatocellular carcinoma: Rescue experiments revealed that upregulated NR4A3 combined with downregulated CDKN2AIP promoted cell proliferation and reversed the progression of cell cycle arrest from G0/G1 to S phase by increasing levels of CDK4/CDK6/CyclinD1/PCNA and decreasing expression levels of p21/p53/γH2AX in HCC cells.