Elevated expression of PD-L1 facilitates the evasion of tumor cells from T-cell-mediated immune surveillance.621 In melanoma, genome-wide hypomethylation induces the upregulation of PD-L1 and the secretion of inhibitory cytokines, concomitant with EMT alterations that collectively foster an immunosuppressive microenvironment.622,623 DNA methylation may also affect the expression of tumor-associated antigens, leading to immune evasion. Here, CD274 is linked to melanoma.