CD8A and neoplasm: In general, CD4+ T helper 1 (Th1) cells, CD8+ cytotoxic T cells, NK cells, M1 macrophages, and dendritic cells are considered to be protective against tumor growth, whereas CD4+ FOXP3+ (forkhead box P3), CD4+ Th2 cells, M2 macrophages, and myeloid-derived suppressor cells (MDSCs) promote tumor growth [19,20].