CTLA4 and melanoma: There are several immune therapies that have successfully been used in the treatment of malignant melanomas, solely as well as combined with other approaches, like cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) inhibitor ipilimumab [5] or programmed cell death protein 1 (PD-1) inhibitors nivolumab and pembrolizumab (Figure 1) [6,7].