The significance of synergizing not‐a IL‐2 and not‐b IL‐2 as a superior anticancer agent in mice models of xenograft tumors, highlighting the α chain as a regulatory switch dedicating “balancing act” on IL‐2:IL‐2R interactions, and opens new avenues for developing combinatorial IL‐2‐based treatments for cancer with less off‐target vascular leak syndrome. This evidence concerns the gene IL2 and cancer.