Journal
BLOOD
Volume 103, Issue 8, Pages 3005-3012Publisher
AMER SOC HEMATOLOGY
DOI: 10.1182/blood-2003-07-2459
Keywords
-
Categories
Funding
- Telethon [E.1254] Funding Source: Medline
Ask authors/readers for more resources
The junctional membrane protein vascular endothelial (VE)-cadherin mediates contact inhibition of growth and inhibits apoptosis of endothelial cells. In this article we show that VE-cadherin induces expression of growth arrest-specific 1 (Gas1), an integral membrane protein up-regulated in nonproliferating cells. By comparing syngenic endothelial cell lines, we found that Gas1 mRNA was increased by 3-fold in VE-cadherin-positive cells in comparison to VE-cadherin-null cells. Ectopic expression of Gas1 in endothelial or 293 cells strongly reduced apoptosis without affecting cell growth. Addition of vascular endothelial growth factor (VEGF) also up-regulated Gas1 and this effect was augmented more so in confluent nonproliferating cells than in sparse cultures. VE-cadherin-blocking antibody partially inhibited VEGF-Induced Gas1, suggesting that VE-cadherin clustering is required for an optimal response to this stimulus. Inhibition of phosphoinositole-3-OH kinase (PI3-kinase) pathway by Wortmannin prevented Gas1 synthesis and the antiapoptotic effect of VEGF, but, in cells ectopically expressing Gas1, Wortmannin was ineffective. Furthermore, inhibition of Gas1 expression by short interfering RNA (siRNA) both in vitro and in allantois organ cultures made endothelial cells refractory to the antiapoptotic effect of VEGF. Overall these data indicate that Gas1 induction by VE-cadherin and VEGF in endothelial cells requires activation of PI3-kinase. Gas1 expression positively correlates with inhibition of endothelial cell apoptosis and may contribute to the integrity of resting endothelium. (C) 2004 by The American Society of Hematology.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available