CTLA4 and metastatic melanoma: Recently, studies demonstrated that tumors from metastatic melanoma patients, who did not respond to anti-CTLA4 and anti-PD-1 therapy, had a high frequency of genomic alterations of IFN-γ pathway genes such as IFNGR1, IFNGR2, IRF1, JAK2 coincident with amplification of IFN-γ signaling pathway suppressor genes, SOCS1 and PIAS458, 59.