Additionally, the reported secretion of cytokines like TGF-β (transforming growth factor β), GM-CSF (granulocyte/macrophage-colony stimulating factor) or TNF-α (tumor necrosis factor α) by MSCs after exposure to ionizing radiation may even have a protective effect on the irradiated tumor cells [46, 47]. This evidence concerns the gene TGFB1 and neoplasm.