The colony stimulating factor (CSF) family members CSF-1, granulocyte-macrophage (GM)-CSF and granulocyte (G)-CSF are essential for the development, differentiation and survival of myeloid cells.96 It is perhaps then not surprising that cancer cells often directly or indirectly upregulate CSF molecules to promote pro-metastatic macrophages and neutrophils and thus to facilitate cancer progression. This evidence concerns the gene CSF2 and cancer.