CD274 and neoplasm: (1) DNA methyltransferase inhibitors, e.g., sensitizing tumors to PD-L1 blockade and elevating the secretion of the immunostimulatory chemokines CXCL10 and CXCL9 (155); (2) histone deacetylase inhibitors, as down-regulating MDSCs, increasing the expression of MHC-I and antigen presentation, and increasing tumor-infiltrating CD8+ T cells (95); and (3) histone methyltransferase Ezh2 inhibitor, as reversing the effects of loss of immunogenicity and antigen presentation (94).