CD8A and cancer: The latter have numerous subgroups, and schematically includes cells fighting cancer cells, such as cytotoxic CD8+ T lymphocytes and pro-inflammatory M1 macrophages, and also cells promoting cancer development (i.e., pro-tumoral immune cells), such as myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), and M2 anti-inflammatory macrophages (for a review, see [119]).