Figure 3.

TGF-β signaling inhibitor A8301 prevents TGF-β-induced mesenchymal shift and enhanced invasive ability of GBM cells. (a) Western blots showing inhibition of TGF-β-induced SMAD2 phosphorylation and expression of the mesenchymal marker Fibronectin by A8301 (0.5 μM). Representative blots are shown of n=3. (b) Phase contrast microscopic pictures at × 10 magnification of U87 and U251 cells treated with TGF-β in the presence or absence of A8301 in comparison with the untreated controls. The inhibitor prevented the phenotypic shift induced by TGF-β. (c) Wound healing assays showing reduced migration of TGF-β-treated U251 cells in the presence of A83-01. Quantification of the wound closure capacity (n=3, ***P<0.001) is shown in (d). (e) Transwell collagen assays showing reduced invasion of U87 cells toward 10% FCS following the addition of A83-01. Membranes were fixed and evaluated for cell numbers. A representative picture of the membranes showing invading U87 cells is shown in (e) and quantification of invasion assay is shown in (f) in which bars represent the mean of in general three independent experiments±S.E.M. (**P<0.01, ***P<0.001, U87 for 10% FCS group; ^##P<0.01, for U87 10% FCS versus 0.1% FCS)