Among various lymphocyte subpopulations, CD4+ and CD8+ T cells with tumor-specific multifunctional effector phenotypes (co-expressing IFN-γ, TNF-α, and IL-2; these antigens are Th1-derived cytokines) are known to contribute to the activation of anti-cancer immunity, which leads to the expansion of memory and effector T cells [31,32,42]. This evidence concerns the gene IL2 and cancer.