The expression of these genes was increased in stage III and IV compared to stage I and II (P < 0.05) (Figure 9B); meanwhile, the expression of the CCNB1 and CHEK1 genes was significantly higher in HCC tissues with vascular invasion than in HCC tissues without vascular invasion (P < 0.05) (Figure 9C). Here, CHEK1 is linked to hepatocellular carcinoma.