First, the expression of AEG-1 and its downstream cyclin D1 are increased in both U251 and U87 malignant glioma cells by treatment with TGF-β1 (5 ng/ml) for 1, 3, 6, 12 and 24 hours (Figure 1C, 1D and 1E). Here, TGFB1 is linked to central nervous system cancer.