CD4 and neoplasm: Besides, immune escape is associated with the low level of CD8+ and CD4+ T cells, dendritic cells (DCs), as well as natural killer (NK) cells, which mediate anti-tumor immune responses, increased immune suppressive cells containing regulatory T cells (Treg), tumorassociated macrophages (TAMs), tumor-associated neutrophils (TANs), and myeloid-derived suppressor cells (MDSCs).