Etk/Bmx transactivates vascular endothelial growth factor 2 and recruits phosphatidylinositol 3-kinase to mediate the tumor necrosis factor-induced angiogenic pathway.

J Biol Chem

Interdepartmental Program in Vascular Biology and Transplantation, Boyer Center for Molecular Medicine, Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.

Published: December 2003

Tumor necrosis factor (TNF), via its receptor 2 (TNFR2), induces Etk (or Bmx) activation and Etk-dependent endothelial cell (EC) migration and tube formation. Because TNF receptor 2 lacks an intrinsic kinase activity, we examined the kinase(s) mediating TNF-induced Etk activation. TNF induces a coordinated phosphorylation of vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and Etk, which is blocked by VEGFR2-specific inhibitors. In response to TNF, Etk and VEGFR2 form a complex resulting in a reciprocal activation between the two kinases. Subsequently, the downstream phosphatidylinositol 3-kinase (PI3K)-Akt signaling (but not signaling through phospholipase C-gamma) was initiated and directly led to TNF-induced EC migration, which was significantly inhibited by VEGFR2-, PI3K-, or Akt-specific inhibitors. Phosphorylation of VEGFR2 at Tyr-801 and Tyr-1175, the critical sites for VEGF-induced PI3K-Akt signaling, was not involved in TNF-mediated Akt activation. However, TNF induces phosphorylation of Etk at Tyr-566, directly mediating the recruitment of the p85 subunit of PI3K. Furthermore, TNF- but not VEGF-induced activation of VEGFR2, Akt, and EC migration are blunted in EC genetically deficient with Etk. Taken together, our data demonstrated that TNF induces transactivation between Etk and VEGFR2, and Etk directly activates PI3K-Akt angiogenic signaling independent of VEGF-induced VEGFR2-PI3K-Akt signaling pathway.

Download full-text PDF

Source
http://dx.doi.org/10.1074/jbc.M310678200DOI Listing

Publication Analysis

Top Keywords

tnf induces
12
vascular endothelial
8
endothelial growth
8
growth factor
8
phosphatidylinositol 3-kinase
8
tumor necrosis
8
tnf receptor
8
etk
8
activation tnf
8
vegfr2 etk
8

Similar Publications

Pulmonary arterial hypertension (PAH) is a syndrome characterized by increased pulmonary vascular resistance and elevated pulmonary artery pressure, ultimately leading to right heart failure and even death. Increasing evidence implicates the fat mass and obesity-associated protein (FTO) in various metabolic and inflammatory pathways; however, its role in pulmonary endothelial function and PAH remains largely unexplored. In this study, we examined the effects of endothelial cell-specific FTO knockout on PAH development.

View Article and Find Full Text PDF

T-cell prolymphocytic leukemia (T-PLL) is an aggressive lymphoid malignancy with limited treatment options. To discover new treatment targets for T-PLL, we performed high-throughput drug sensitivity screening on 30 primary patient samples ex-vivo. After screening over 2'800 unique compounds, we found T-PLL to be more resistant to most drug classes, including chemotherapeutics, compared to other blood cancers.

View Article and Find Full Text PDF

Background: This study tested the hypothesis that extracorporeal shockwave therapy (ECSWT) effectively rescues critical limb ischemia (CLI) in mice through the upregulation of GPR120, which protects against inflammation and angiogenesis to restore blood flow in the ischemic area.

Methods And Results: Compared with the control, ECSWT-induced GPR120-mediated anti-inflammatory effects significantly suppressed the expression of inflammatory signaling biomarkers (TAK1/MAPK family/NF-κB/IL-1β/IL-6/TNF-α/MCP-1) in HUVECs, and these effects were abolished by silencing GPR120 or by the GPR120 antagonist AH7614 (all P < 0.001).

View Article and Find Full Text PDF

Induction of M1 polarization in BV2 cells by propofol intervention promotes perioperative neurocognitive disorders through the NGF/CREB signaling pathway: an experimental research.

Int J Surg

January 2025

Department of Anesthesiology, Jiangxi Cancer Hospital & Institute, Jiangxi Clinical Research Center for Cancer, The Second Affiliated Hospital of Nanchang Medical College, Jiangxi Key Laboratory of Oncology, Nanchang, Jiangxi Province, China.

Nerve growth factor (NGF) is critical in regulating the homeostasis of microglial cells. It activates various signaling pathways that mediate the phosphorylation of cAMP response element-binding protein (CREB) at key regulatory sites. The decrease in phosphorylated CREB (p-CREB) expression is linked to neuroinflammatory responses.

View Article and Find Full Text PDF

Background: Chronic soft tissue injury is characterized by sterile inflammation and pain. Gua sha with Masanggoubang oil (GSMO) treatment has been found to possess anti-inflammatory and analgesic effects.

Objectives: To explore the mechanism of GSMO in chronic soft tissue injuries.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!