Ipilimumab is a highly successful antibody against CTLA-4 approved by the FDA for treatment of melanoma [reviewed in (94)] and for combination therapy with Nivolumab (anti-PD-1) for advanced renal cell carcinoma, MSI-H/dMMR metastatic colorectal cancer, hepatocellular carcinoma, metastatic NSCLC, and malignant pleural mesothelioma (95) [reviewed in (96)]. The gene discussed is CTLA4; the disease is melanoma.