It is enriched in FOXP3+CD4+T, PDCD1+CD8+, and GZMK+CD8+T cells, affects the immune microenvironment of HCC by regulating the expression of target genes JAK2, SLC6A6, KCND1, MEIS3, and RIN1, and participates in the immune escape process in HCC (46). The gene discussed is PDCD1; the disease is hepatocellular carcinoma.