These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Endostatin-induced tyrosine kinase signaling through the Shb adaptor protein regulates endothelial cell apoptosis. Author: Dixelius J, Larsson H, Sasaki T, Holmqvist K, Lu L, Engström A, Timpl R, Welsh M, Claesson-Welsh L. Journal: Blood; 2000 Jun 01; 95(11):3403-11. PubMed ID: 10828022. Abstract: Endostatin, which corresponds to the C-terminal fragment of collagen XVIII, is a potent inhibitor of angiogenesis. Fibroblast growth factor-2 (FGF-2)-induced angiogenesis in the chicken chorioallantoic membrane was inhibited by endostatin, but not by an endostatin mutant R158/270A, lacking heparin-binding ability. Endostatin was internalized by endothelial cells, but not by mouse fibroblasts. Treatment of murine brain endothelial (IBE) cells with endostatin reduced the proportion of cells in S phase, whereas growth-arrested IBE cells in collagen gels treated with endostatin displayed enhanced tubular morphogenesis. IBE cells overexpressing Shb, an adaptor protein implicated in angiostatin-induced apoptosis, displayed elevated apoptosis and decreased tubular morphogenesis in collagen gels in response to endostatin when added together with FGF-2. Induction of apoptosis was dependent on the heparin-binding ability of endostatin and the expression of Shb with a functional Src homology 2 (SH2)-domain. Endostatin treatment for 10 minutes or 24 hours induced tyrosine phosphorylation of Shb and formation of multiprotein complexes. An Shb SH2 domain fusion protein precipitated a 125-kd phosphotyrosyl protein in endostatin-treated cells. The 125-kd component either contained intrinsic tyrosine kinase activity or occurred in complex with a tyrosine kinase. In conclusion, our data show that endostatin induces tyrosine kinase activity and enhanced apoptosis in FGF-treated endothelial cells.[Abstract] [Full Text] [Related] [New Search]