The expression levels of the proteins encoded by the 18 genes in HCC and normal liver tissues are shown in Supplementary Fig. S5 based on the data from The Human Proteins Atlas (http://www.proteinatlas.org/about), among which no protein expression information of HCFC1, NUP205, ECT2, PRIM2, MCM8 were provided. The gene discussed is PRIM2; the disease is hepatocellular carcinoma.