The expression of RRM2 in hepatocellular carcinoma and normal tissues was analyzed, and the difference in RRM2 expression levels was confirmed (P <0.001, Figures 1A, B); RRM2 expression was higher in LIHC (Liver Hepatocellular Carcinoma) tissues than in normal tissues (P <0.001, Figure 1A). The gene discussed is RRM2; the disease is hepatocellular carcinoma.