Such as in nonsmall cell lung cancer (NSCLC) as well as hepatocellular carcinoma (HCC), a malfunction CD8 + T cell population was discovered to be positively related to high levels of expression of suppressor receptor genes (PD1, PD-L1, LAG3, CTLA4, TIGIT, and HAVCR2) [41, 42]. This evidence concerns the gene TIGIT and hepatocellular carcinoma.