Various factors might determine the effect of TGF-β1 including TGF-β1 receptors (normal or diminished), target cell types (normal or tumoral), TGF-β1 dosage, and immune response: while it is mostly tumor suppressor in early tumors, it facilitates tumorigenesis in later stages7,18,23,36–38,41,44,109–112; for instance it might enhance36,41,43 or inhibit40,41 tumor cell invasion. The gene discussed is TGFB1; the disease is neoplasm.