Numerous studies have identified cytotoxic CD8+T lymphocytes (CTL), CD4+T helper cells 1 (Th1 cells), and natural killer cells (NK) as primarily exerting anti-cancer effects, while CD4+Th2 cells and myeloid-derived suppressor cells (MDSCs) are associated with pro-cancer effects 57. The gene discussed is CD8A; the disease is cancer.