PDCD1 and melanoma: LAG-3+ TIL numbers are increased in MHC-II+ tumors (lung cancer, melanoma, and breast cancer), and MHC-II+ tumors acquire immunosuppressive signals through LAG-3; thus, combined PD-1/PD-L1 and LAG-3 blockade can provide a particular advantage against MHC-II+ tumors (95).