IFNG and melanoma: In this respect, IFN-γ produced by cells in the tumor microenvironment in response to ICIs has a substantial influence on both immune and melanoma cells, leading to beneficial effects supporting the overall response to immunotherapy by increasing MHC expression/antigen presentation, recruiting additional T-cells to the tumor, and inducing direct antiproliferative effects and apoptosis in melanoma cells (Fig. 3).