Suppressive immune cells in the TME often preferably express pro-tumor Th2 secreted cytokines, such as IL-4 and IL-13, rather than anti-tumor Th1 (e.g., IL-2 production), or secreted cytokines like IFN-γ and tumor necrosis factor-β (TNF-β) [140, 141]. Here, IL2 is linked to neoplasm.