CDKN1A and hepatocellular carcinoma: To further verify the direct binding between miR-520h with CDKN1A 3′-UTR, we first compared the CDKN1A expression between HCC (Hep3B, HepG2, and Huh7) and normal liver (LO2) cells, which showed that CDKN1A mRNA expression was significantly down-regulated in HCC cells than in normal liver cells (Figure 4b).