A CSF-cytokine code predicts macrophage response polarity and tumor outcomes

Tumor-associated macrophages can either promote or suppress cancer, but current therapeutic approaches fail because we lack a predictive framework for macrophage function. The prevailing M1/M2 paradigm oversimplifies how macrophage developmental origin (ontogeny) and local cytokines interact to determine anti- versus pro-tumor responses. We systematically mapped eight reference macrophage states by differentiating mouse bone marrow cells with either M-CSF or GM-CSF, followed by polarization with four key cytokines (IFN‑γ, IL‑4, IL‑10, TGF‑β). Using integrated transcriptomics, 3D tumor spheroids, and experimental metastasis models, we discovered that macrophage ontogeny determines whether cytokines promote or suppress tumor growth. Most strikingly, IL-4 induced opposite effects: promoting tumor growth, invasion, and metastasis in M-CSF macrophages while suppressing these processes in GM-CSF macrophages. This ontogeny-dependent polarity switch also affected IL-10 responses, whereas IFN‑γ remained consistently anti-tumor and TGF‑β consistently pro-tumor across both lineages. These findings establish an "ontogeny‑cytokine code" that predicts macrophage function based on developmental origin and cytokine environment. By identifying ontogeny as a master determinant of cytokine responses, this work provides a new framework for precision cancer immunotherapy.