CD8A and neoplasm: In addition, there are several unfavorable immune subsets that characterize their potent immune suppressive activity in the tumor microenvironment, which involved in T regulatory cells, alternatively activated M2 macrophages, and myeloid-derived suppressor cells (MDSC) by preventing the antitumor activity of effectors CD4+ T cells and CD8+ T cells (Gun et al., 2019).