OBJECTIVE Plasminogen activator inhibitor-1 (PAI-1) regulates angiogenesis via effects on extracellular matrix proteolysis and cell adhesion. However, no previous study has implicated PAI-1 in controlling vascular endothelial growth factor (VEGF) signaling. We tested the hypothesis that PAI-1 downregulates VEGF receptor-2 (VEGFR-2) activation by inhibiting a vitronectin-dependent cooperative bi...

Vascular endothelial growth factor (VEGF)/vascular permeability factor induces both angiogenesis and vascular permeability mainly through VEGF receptor (VEGFR)-2 activation. VEGF binds VEGFR-1 as well, but the importance of VEGFR-1 signaling in vascular permeability has been largely neglected. Here, we report the purification and characterization of a novel VEGF-like protein from Trimeresurus f...

Vascular endothelial growth factor (VEGF) is a key angiogenic factor in a variety of solid tumors, making it one of the most attractive therapeutic targets. VEGF promotes the proliferation, survival, and differentiation of vascular endothelial cells by stimulating autophosphorylation and activation of VEGF receptor-2 (VEGFR-2, fetal liver kinase-1, and kinase insert domain-containing receptor)....

Vascular endothelial growth factors (VEGFs) and their tyrosine kinase receptors (VEGFR-1-3) are central mediators of angiogenesis and lymphangiogenesis. VEGFR-3 ligands VEGF-C and VEGF-D are produced as precursor proteins with long N- and C-terminal propeptides and show enhanced VEGFR-2 and VEGFR-3 binding on proteolytic removal of the propeptides. Two different proteolytic cleavage sites have ...

BACKGROUND To evaluate whether Contrast Enhanced Ultrasund (CEUS) with microbubbles (MBs) targeted to VEGFR-2 is able to characterize in vivo the VEGFR-2 expression in the tumor vasculature of a mouse model of thyroid cancer (Tg-TRK-T1). METHODS Animal protocol was approved by Institutional committee on Laboratory Animal Care. Contrast-enhanced ultrasound imaging with MBs targeted with an ant...

Vascular endothelial growth factor (VEGF) plays a vital role in tumor angiogenesis. VEGF is produced by human melanomas, and the VEGF receptor 2 (VEGFR-2) is expressed by most advanced stage melanomas, suggesting the possibility of an autocrine loop. Here, we show that bevacizumab, an anti-VEGF antibody, inhibits proliferation of VEGFR-2(+) melanoma cell lines by an average of 41%; however, it ...

Emerging data suggest that a subset of circulating human CD34(+) cells have phenotypic features of endothelial cells. Whether these cells are sloughed mature endothelial cells or functional circulating endothelial precursors (CEPs) is not known. Using monoclonal antibodies (MoAbs) to the extracellular domain of the human vascular endothelial receptor-2 (VEGFR-2), we have shown that 1.2 +/- 0.3%...

Vascular endothelial growth factor (VEGF)-C is necessary for lymphangiogenesis, and excess VEGF-C has been shown to be ameliorative for edema produced by lymphatic obstruction in experimental models. However, it has recently been shown that edema can resolve in the mouse tail even in the complete absence of capillary lymphangiogenesis when distal lymph fluid crosses the regenerating wound site ...

Vascular endothelial growth factor (VEGF) receptor 3 (VEGFR-3), a receptor for VEGF-C, was shown to be essential for angiogenesis as well as for lymphangiogenesis. Targeted disruption of the VEGFR-3 gene in mice and our previous study using an antagonistic monoclonal antibody (MoAb) for VEGFR-3 suggested that VEGF-C/VEGFR-3 signals might be involved in the maintenance of vascular integrity. In ...

Oxygen administration to immature neonates suppresses VEGF-A expression in the retina, resulting in the catastrophic vessel loss that initiates retinopathy of prematurity. To investigate the mechanisms responsible for survival of blood vessels in the developing retina, we characterized two VEGF-A receptors, VEGF receptor-1 (VEGFR-1, also known as Flt-1) and VEGF receptor-2 (VEGFR-2, also known ...