This study found that the expression of prognostic CRGs in the TCGA-LIHC cohort was positively correlated with the expression of PD-1 (PDCD1), PD-L1 (CD-274) and CTLA-4, suggesting that the prognosis of HCC patients with high expression of CRGs should be improved by immunotherapy targeting immune checkpoints. The gene discussed is PDCD1; the disease is hepatocellular carcinoma.