As shown in Figure 3A, the expression level of Plac9 was higher in the primary liver carcinoma cell line PLC relative to human hepatoma cells SK-HEP-1, SMMC-7721, Lm3 and the normal liver cell line QSG-7701; moreover, in HEP-G2 cells and the human embryonic liver cell line L02, Plac9 expression was almost undetectable. This evidence concerns the gene PLAC9 and hepatocellular carcinoma.