Retinoic Acid Mediates Regulation of Network Formation by COUP-TFII and VE-Cadherin Expression by TGFβ Receptor Kinase in Breast Cancer Cells
Figure 3
TGFβR1 kinase activity is necessary for VE-cadherin expression.
A one hour pre-treatment with SB431542, a TGFβR1 kinase specific inhibitor, prior to a 48 hour RA treatment results in a loss of VE-cadherin expression in a dose-dependent manner (a). Treatment with SB431542 decreases PAI-1 activity, confirming TGFβR1 blockade (b).The samples are as follows: 1 - Control; 2 - RA; 3 - Control, 10 µM SB431542; 4 - RA, 10 µM SB431542; 5 - Control - 50 µM SB431542; 6 - RA, 50 µM SB431542. Treatment with 10 ng/ml of TGFβ, alone, does not induce VE-cadherin expression in the absence of RA treatment (c).