CTLA4 and melanoma: The results showed that the response to anti‐CTLA‐4 treatment requires melanoma cells to strongly express MHC class I molecules, while the response to anti‐PD‐1 treatment is related to IFN‐γ‐mediated immune activation, including the expression of MHC class II molecules and innate immunity produced when MHC class I molecules are immune compromised.62