It has a high affinity and binding specificity for PD-1 and can block the interaction between PD-1 and its ligand, terminate the PD-1 immunosuppressive signal caused by the interaction between PD-1 and PD-L1 in T cells, and restore the immune response against tumors, thereby enhancing the killing effect on tumor cells [21]. This evidence concerns the gene CD274 and neoplasm.