TP53 and hepatocellular carcinoma: KEGG annotation analysis of DEGs in HCC revealed that the pathway mainly including retinol metabolism (P = 4.21E-05), drug metabolism-cytochrome P450 (P = 5.95E-05), cell cycle (P = 2.44E-04), and the p53 signaling pathway (P = 5.59E-04) (Fig. 2A).