CD8A and neoplasm: The tumor microenvironment harbors a diverse array of immune cell types, including adaptive immune cells like CD8+T cells, CD4+T cells, regulatory T cells (Tregs), and B cells, as well as myeloid immune cells such as macrophages, dendritic cells (DCs), and myeloid-derived suppressor cells (MDSCs), and innate immune cells such as natural killer (NK) cells and innate lymphoid-like cells [15].