We validated these observations in melanoma cells with different p53 status, and confirmed that p53KO from A375 cells with wt p53 causes a four- to fivefold increase in membrane PD-L1 (P < 0.01) (Fig. 1A, Fig. S2) and total PD-L1 protein levels (Fig. 1B). Here, TP53 is linked to melanoma.