Figure 3. Regulations of bortezomib on epithelial-mesenchymal transition of APRE-19. A: Western blot analysis after treatment with various concentrations of bortezomib in the presence of transforming growth factor-β1
(TGF-β1, 10 ng/ml). At a concentration of 20 nM, treatment with bortezomib resulted in significant downregulation of mesenchymal
factors (N-cadherin, α-smooth muscle actin [SMA], β-catenin, and vimentin) and upregulation of epithelial markers (ZO-1 and
occludin). B: Quantification of western blot signals with densitometry. Bortezomib induced statistically significant upregulation of ZO-1
and occludin and downregulation of N-cadherin, α-SMA, β-catenin, and vimentin in the presence of TGF-β1. *p<0.05, **p<0.01,
and ***p<0.001 with an independent t test, n=3, standard error, C: Immunocytochemical analysis confirmed the western blot analysis results. Bortezomib (20 nM) statistically significantly
increased the expression of ZO-1 and occludin and decreased that of N-cadherin, α-SMA, β-catenin, and vimentin in the presence
of TGF-β1.