In the recent years, various types of immunotherapies have come to the stage of HCC treatment, such as Lymphocyte-activation gene 3 (LAG-3), T cell Ig and ITIM domain (TIGIT) or T cell immunoglobulin domain and mucin domain-3 (TIM-3) blockade, chimeric antigen receptor T cell (CAR-T) therapy, adoptive cell therapies using NK cells, NKT cells, or γδ T cells, oncolytic virotherapy, cancer vaccines, etc (76, 77). The gene discussed is HAVCR2; the disease is hepatocellular carcinoma.