CD4 and neoplasm: T cells, which include pro-tumor FOXP3+ regulatory cells, CD4+ Th2 helper cells, and Th17 cells, as well as antitumor CD8+ memory cells, CD4+ Th1 helper cells, and γδ T cells, account for up to 10% of the total tumor cell population, however, can also be found in substantial concentrations along the tumor periphery [44].