The effector function of CD8+ T cells could be boosted by a prodrug formulation of recombinant IL-2 (NKTR-214) that proved to increase the tumor-fighting potential of a 16 Gy single dose, even in contralateral unirradiated tumor site among mice with implanted fibrosarcoma or colorectal cancers [91]. This evidence concerns the gene IL2 and neoplasm.