TGF-β1 up-regulates the expression of MMP-9, PAI-1, and α-SMA in α3 wt cells but not in H245A mutant cells. (A) TGF-β1 induces expression of MMP-9, PAI-1, and α-SMA in α3 wt and G163A mutant cells but not in H245A mutant cells. Serum-starved cells were stimulated with 4 ng/ml TGF-β1 for 48 h. Supernatants were collected and concentrated 10 times. Cells were lysed in RIPA buffer and blotted for integrin α3, E-cadherin, PAI-1, α-SMA, and β-actin. MMP-9 was detected by gelatin zymography. The aforementioned blots have been repeated at least three times with a similar pattern. (B) Time course of mRNA expression in α3 wt and H245A cells stimulated with TGF-β1. Serum-starved cells were stimulated with 4 ng/ml TGF-β1 for different time periods. RNA was extracted from the cells and used for direct Taqman real-time PCR analysis. Data shown are representative of four independent experiments.