Figure 6

TGFβ modulates integrin β4 expression in a Par6- and TβRI-dependent manner. Subconfluent monolayers of the indicated NMuMG-derived cell lines were treated for 48 hours (A) or 144 hours (B) with control media (DMSO alone), TGFβ1 (TGFβ, 5 ng/ml), the TβRI/Smad2 inhibitor SB-431542 (SB, 10 μM) or TGFβ + SB. A and B show levels of β4 integrin (β4), E-cadherin (E-cad), β1 integrin (β1), phospho-Smad2 (pSmad2, Ser465/467) and Smad2 as determined by immunoblotting; α-tubulin was used as loading control. C. Graphs represent the average relative β4 integrin expression after 48-hour (left) or 144-hour (right) treatment as determined by band densitometry for n = 3 independent experiments. Relative β4 integrin expression was calculated as the ratio of β4 integrin to α-tubulin. The value for DMSO control was set to 1 for each cell line. Two-way ANOVA for all cell lines and treatments was significant (p < 0.05) for the 144-hour treatment. Bonferroni post test compared differences between control and treatment for each cell line, **p < 0.001.