qRT-PCR (Figure 2D–G) and immunohistochemical staining (Figure 2H) of the clinical samples verified the higher CDKN2A, CDKN2B, CDKN2C, and CDKN2D expression in HCC than in adjacent normal liver tissues at both the mRNA and protein levels. Here, CDKN2D is linked to hepatocellular carcinoma.