CD8A and melanoma: The immune-modulatory effects of MEKi are mixed, leading to decreased T-cell proliferation, activity, and priming, while also increasing the accumulation and survival of CD8+ TILs, enhancing MHC and melanoma antigen expression, and downregulating immunosuppressive cytokines (Boni et al., 2010; Ebert et al., 2016; Liu et al., 2015; Vella et al., 2014).