Our data not only showed that overexpression of NR4A3 upregulated CDKN2AIP resulting in cell cycle arrest at the G0/G1 to S phase transition, but also suggested that NR4A3 promoted p21, p53 and γH2AX expressed through the regulation of CDKN2AIP in HCC cells. This evidence concerns the gene CDKN1A and hepatocellular carcinoma.