Anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) antibodies, on the other hand, have shaped novel anti-tumor treatment, and they can deplete Tregs in the tumor micro-environment, so they show a novel direction of targeted cancer therapy [41, 42].CD8+ T cells were found to increase in patients treated with anti-PD-1 and anti-PD-L1 antibodies. This evidence concerns the gene CTLA4 and cancer.