Deletion of the hypoxia-response element in the vascular endothelial growth factor promoter causes motor neuron degeneration.

Hypoxia stimulates angiogenesis through the binding of hypoxia-inducible factors to the hypoxia-response element in the vascular endothelial growth factor (Vegf) promotor. Here, we report that deletion of the hypoxia-response element in the Vegf promotor reduced hypoxic Vegf expression in the spinal cord and caused adult-onset progressive motor neuron degeneration, reminiscent of amyotrophic lateral sclerosis. The neurodegeneration seemed to be due to reduced neural vascular perfusion.

Vascular endothelial growth factor (VEGF) modulation by targeting hypoxia-inducible factor-1alpha--> hypoxia response element--> VEGF cascade differentially regulates vascular response and growth rate in tumors.

Although tumors can activate vascular endothelial growth factor (VEGF) promoter in host stromal cells, the relative contribution to VEGF production of host versus tumor cells and the resulting vascular response have not been quantitated to date. To this end, we implanted VEGF-/- and wild-type (WT) embryonic stem (ES) cells in transparent dorsal skin windows in severe combined immunodeficient mice. VEGF-/- ES cell-derived tumors produced approximately 50% of VEGF compared with the WT tumors, suggesting significant contribution of host stromal cells.

Targeted deficiency or cytosolic truncation of the VE-cadherin gene in mice impairs VEGF-mediated endothelial survival and angiogenesis.

Vascular endothelial cadherin, VE-cadherin, mediates adhesion between endothelial cells and may affect vascular morphogenesis via intracellular signaling, but the nature of these signals remains unknown. Here, targeted inactivation (VEC-/-) or truncation of the beta-catenin-binding cytosolic domain (VECdeltaC/deltaC) of the VE-cadherin gene was found not to affect assembly of endothelial cells in vascular plexi, but to impair their subsequent remodeling and maturation, causing lethality at 9.5 days of gestation.