As Fig. 3 shows, scRNA-seq confirms that tumor tissues contain complex immune components including innate immune cells, such as dendritic cells (DCs), immature dendritic cells (iDCs), activated dendritic cells (aDCs), eosinophils and neutrophils, mast cells, macrophages, natural killer cells (NK; NKCD56 dim cell, NKCD56 bright cell); adaptive immune cells, such as T helper cells Th1 and Th2, regulatory T cells (Treg), CD8 + T cells, central memory T cells (Tcm), memory effector T cells (Tem), T follicular helper cells (Tfh) and γδ T cells, etc [87–90]. Here, CD8A is linked to neoplasm.