In some cancers, like non-small-cell lung carcinoma (NSCLC) and malignant melanoma, immunotherapy, such as programmed death-1 (PD-1), programmed death ligand-1 (PD-L1) inhibitors and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) showed outstanding antitumor effects (Barbee et al., 2015; Garon et al., 2015). The gene discussed is CTLA4; the disease is cancer.