Checkpoint inhibitors, which target the programmed cell death pathway (PD-1 and PD-L1) and the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), are effective in the treatment of several types of cancers, including melanoma, RCC, and non-small cell lung cancer126,127. The gene discussed is CTLA4; the disease is renal cell carcinoma.