Finally, reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting analyses showed that PBOV1 mRNA and protein levels were markedly upregulated in multiple HCC cell lines including Hep3B, BEL7402, SNU423, SMMC-7721, PLC/PRF/5, Huh7, HLE, HLF, HepG2.2.1, SK-Hep1, and HepG2, as compared with human normal hepatocyte cell lines (L02 and HHL-5) (Fig. 1e, Supplementary Fig. 1b). The gene discussed is PBOV1; the disease is hepatocellular carcinoma.