IMCs are induced by tumor-derived inflammatory factors [e.g., VEGF, granulocyte-macrophage colony-stimulating factor (GM-CSF), prostaglandins, interleukin (IL)-1β, IL-6, IL-10, TGF-β, S100A8, and S100A9] (2, 6, 7) that stimulate tumor growth and myelopoiesis and block the differentiation of IMCs into mature effector cells such as DCs, macrophages, and granulocytes (8, 9). This evidence concerns the gene CSF2 and neoplasm.