Notable examples include immune checkpoint inhibitors (e.g., anti-CTLA-4, anti-PD-1/PD-L1 antibodies) [9,10,11], chimeric antigen receptor (CAR) T-cell therapy [12,13,14], and monoclonal antibody-based treatments [15], all of which have significantly improved patient outcomes in various cancers. This evidence concerns the gene CTLA4 and cancer.