TOP2A and hepatocellular carcinoma: Then, we selected 4 hub genes based on the KEGG pathways (Table 5) of the top 15 genes to verify the expression level in liver tissues between HCC and healthy people using GEPIA, and Figures 5(a)–5(d) showed that compared to normal group, the expression level of TOP2A, CCNB1, KIF4A, and CCNB2 significantly elevated in HCC patients.