It is known that the astrocytes or glioma cells induce and strengthen BBB functions of brain endothelial cells via a range of released factors, including transforming growth factor-β (TGFβ), glial-derived neurotrophic factor (GDNF) and basic fibroblast growth factor (bFGF) [16–18]. The gene discussed is TGFB1; the disease is central nervous system cancer.