G-CSF was reported to increase proliferation and growth of breast cancer cells, both by directly acting on the cancer cells as well as by recruiting immune cells, like myeloid-derived suppressor cells (MDSCs), which inhibit T cell activation and proliferation, thus enabling cancer immune evasion, and tumor-associated macrophages, which promote cancer cell growth [47,48,49]. This evidence concerns the gene CSF3 and neoplasm.