CTLA4 and melanoma: Also, in patients responsive to anti-PD-1 therapy, there was a notable upregulation of the IFN-γ-related gene signature, distinguishing them from non-responders.102–104 Moreover, resistance to anti-CTLA-4 in melanoma patients is often associated with deficiencies in the IFN-γ pathway, including the loss of IFNGR, JAK2, IFIT, MTAP, and IRF1 genes.