In tumor microenvironment granulocyte-macrophage colony-stimulating factor (GM-CSF) is produced by MDSC cells, M2 macrophages, type 3 innate lymphoid cells (ILC3) cells, neoplastic colonic epithelial cells, T cells, mast cells, NK cells, endothelial cells, and fibroblasts [174], together with a wide variety of cancer cell types [175]. The gene discussed is CSF2; the disease is cancer.