Because TUG1 and PD-L1 expression was higher in the MHCC-97H and HCC-LM3 cell lines than in the Huh-7 and SMCC-7721 cell lines, we selected the MHCC-97H and HCC-LM3 HCC cell lines for further study. The gene discussed is TUG1; the disease is hepatocellular carcinoma.