| First Author | Kocic J | Year | 2012 |
| Journal | Eur J Cancer | Volume | 48 |
| Issue | 10 | Pages | 1550-7 |
| PubMed ID | 21798735 | Mgi Jnum | J:188891 |
| Mgi Id | MGI:5442498 | Doi | 10.1016/j.ejca.2011.06.043 |
| Citation | Kocic J, et al. (2012) SMAD3 is essential for transforming growth factor-beta1-induced urokinase type plasminogen activator expression and migration in transformed keratinocytes. Eur J Cancer 48(10):1550-7 |
| abstractText | Transforming growth factor-beta1 (TGF-beta1) stimulates the extracellular matrix degrading proteases expression and cell migration in order to enhance cancer cells malignancy. In the present study, we analysed the role of TGF-beta1-induced Smad3 activation in the urokinase type plasminogen activator (uPA) production, as well as in cell migration and E-cadherin downregulation in transformed PDV keratinocyte cell line. TGF-beta1 signalling was interfered by the chemical inhibitor of the TGF-beta1-receptor 1 (ALK5), SB505124, and the specific Smad3 inhibitor, SiS3. Our results showed that TGF-beta1 stimulates uPA expression directly through ALK5 activation. The inhibition of Smad3 strongly reduced the capacity of TGF-beta1 to stimulate uPA expression, in parallel decreasing the uPA inhibitor plasminogen activator inhibitor type 1 (PAI-1) expression. In addition, the transient expression of dominant negative Smad3 mutant inhibited the TGF-beta1-induced uPA promoter transactivation. Moreover, Smad3-/- mouse embryonic fibroblasts were refractory to the induction of uPA by TGF-beta1. The inhibition of both ALK5 and Smad3 dramatically blocked the TGF-beta1-stimulated E-cadherin downregulation, F-actin reorganisation and migration of PDV cells. Taken together, our results suggest that the TGF-beta1-induced activation of Smad3 is the critical step for the uPA upregulation and E-cadherin downregulation, which are the key events preceding the induction of cell migration by TGF-beta1 in transformed cells. |
