Interestingly, after treatment with U0126, which is an efficient inhibitor of the ERK pathway, we observed that as the activation of the ERK signaling pathway was inhibited, the increase in the malignant phenotype of HCC cells induced by the overexpression of PSMD12 was also significantly downregulated (Figure 4a, b, c, d). The gene discussed is MAPK1; the disease is hepatocellular carcinoma.