MEK inhibition led to increased MHC expression and was synergistic with anti-PD-1 immunotherapy in syngeneic models.39 Similarly, immunotherapy was synergistic with BRAF and MEK inhibition in preclinical melanoma models.49 However, the mechanistic basis for how MEK inhibition can promote immunotherapy success remains poorly understood, particularly in the context of NSCLC. This evidence concerns the gene HLA-C and melanoma.