CSF1 and neoplasm: Pro-tumour immune populations include M2 macrophages, N2 neutrophils, regulatory T cells and myeloid-derived suppressor cells; each contributing to the tumour aggressiveness via key effector molecules like colony stimulating factor-1, interleukin (IL)-6, metalloproteases, vascular endothelial growth factor, prostaglandin E2, transforming growth factor-β and IL-10 [89].