IL7 and cancer: Meanwhile, elevated circulating concentrations of IL-7 in physically active individuals (109, 127) may also be beneficial as IL-7 does not support the survival and function of TREG cells, due to downregulation of IL-7 receptor (CD127) on TREG cells (200, 201) whereas it favours the maintenance of memory T cells, thus enhancing immune effector capabilities to maintain cancer in equilibrium (8, 41, 42).