IL2 and cancer: Studies have reported that proteins secreted by cancer cells can promote cancer proliferation, stemness, and metastasis.[6] In the context of cancer immunity, various secreted cytokines, including interferon alpha (IFN‐α), IFN‐γ, interleukin‐2 (IL‐2), and granulocyte macrophage‐colony stimulating factor (GM‐CSF), play crucial roles in mediating immune responses and have been employed in cancer immunotherapy.