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A potential mechanism involved in hemangioma formation is the alteration of the FLK1 signaling pathway in endothelial and/or pericytic cells. A potential mechanism involved in hemangioma formation is the alteration of the FLK1 signaling pathway in endothelial and/or pericytic cells. A set of loop-1 and -3 structures in the novel vascular endothelial growth factor (VEGF) family member, VEGF-ENZ-7, is essential for the activation of this protein's signaling. Altered expression of vascular endothelial growth factor and FLK-1 receptor in chronically hypoxic carotid body. An immunohistochemical analysis of VEGFR2 in pituitary adenomas was made. Axl stimulation by GAS6 results in inhibition of the ligand-dependent activation of vascular endothelial growth factor (VEGF) receptor 2 and the consequent activation of an angiogenic program in vascular endothelial cells. Blockade of either VEGF or its receptors with neutralizing antibodies significantly reduced cell viability and increased apoptosis levels of the VEGFR-positive thyroid tumour cell line. Blood levels correlate with lymph node involvement in colorectal cancer. CLL B cells consistently express VEGFR2 mRNA; co-expression of angiogenic molecules and receptors suggest autocrine pathways of stimulation. Constitutive activation of Stat3alpha in brain tumors: localization to tumor endothelial cells and activation by the endothelial tyrosine kinase receptor (VEGFR-2). Data suggest that periostin-mediated angiogenesis derives in part from the up-regulation of the vascular endothelial growth factor receptor Flk-1/KDR by endothelial cells through an integrin alpha(v)beta(3)-focal adhesion kinase signaling pathway. Expression of vascular endothelial growth factor receptor Flk1/KDR is induced by shear stress through the CT-rich Sp1 binding site. Fluid shear stress induced upregulation requires Sp1 transcription factor binding to specific response elements in the 5' regulatory region. Gq/11 proteins mediate KDR tyrosine phosphorylation and KDR-mediated HUVEC proliferation through interaction with KDR. In chronic lower limb ischemia, growth factor-1 (IGF-1) and IGF-2, were upregulated in atrophic and regenerating myocytes together with attenuated HIF, VEGF, and VEGFR-2 expression in the same cells. In this study we give evidence of Flt-1 and KDR receptors in platelets. Increased expression of KDR is associated with an aggressive angiogenic phenotype in melanoma. Inhibition by flk-1 kinase inhibitor SU1498 and failure of placental growth factor (PlGF) to up-regulate DAF confirmed the role of VEGF-R2 in VEGF-mediated DAF up-regulation. Intact caveolae are required for the VEGF/VEGFR-2-mediated MEK/ERK signaling cascade. Involvement of VEGFR-2 (kdr/flk-1) but not VEGFR-1 (flt-1) in VEGF-A and VEGF-C-induced tube formation by human microvascular endothelial cells in fibrin matrices in vitro. KDR is constitutively phosphorylated and located at the nucleus of VEGF-producing leukemias; a KDR-specific intracellular inhibitor failed to block KDR nuclear IMPORT, but inhibited the constitutive activation of MAPK/Erk and PI3-kinase/AKT pathways. KDR plays a key role in regulating the proliferation of HGCC and HVEC. KLF2 is a regulator of VEGFR2/KDR and has a role in regulating angiogenesis. NRP-1 modulates VEGFR-2 signaling-dependent mitogenic functions of VEGF and regulates endothelial cell adhesion to extracellular matrix proteins independently of VEGFR-2. Nedd4-mediated vascular endothelial growth factor receptor-2 degradation is prevented by Grb10. Our data support a role for KDR in oviduct angiogenesis. PPARgamma1 has bifunctional properties in the regulation of KDR gene expression mediated via interaction with both Sp1 and Sp3. Phosphorylated ERK1/2 was further associated with the presence of VEGFR2 (cohorts II and III) and the degree of phosphorylated Ets-2, indicating in vivo, a signalling cascade from VEGFR2 via ERK1/2 to Ets-2 phosphorylation. Shb binds to tyrosine 1175 in the VEGFR-2, which regulates VEGF-induced formation of focal adhesions and cell migration, of which the latter occurs in a phosphatidylinositol 3-kinase-dependent manner. Specific VEGFR2 expression, examined in 27 B-CLL samples, was positive in 26 of them. The VEGF transduction pathway may be very active in CLL cells. Both its paracrine & autocrine pathways may contribute to their enhanced survival. Staining for the receptors VEGFR-1 and VEGFR-2 was positive in large lymphoid cells in stage IV non-Hodgkin lymphoma. TNF induces transactivation between Etk and VEGFR2, and Etk directly activates PI3K-Akt angiogenic signaling independent of VEGF-induced VEGFR2-PI3K-Akt signaling pathway. Targeting the release of VEGF from tumor epithelial cells as well as blocking interactions between VEGF and VEGFR-2 on both endothelial and tumor epithelial cells may facilitate the development of antiangiogenic therapies for breast tumors. Tgf-beta mediated repression of flk-1/KDR and mediated repression of flk-1/KDR and VEGF signaling involves the inducible formation of inhibitory Hex-GATA signaling Hex-GATA involves the formation of Hex-GATA complexes. The VEGFR2, through interaction with VEGF, regulated adhesive and migratory properties of the cancer cells. The binding of VEGF to its receptor, KDR, is necessary and sufficient to induce the gene expression profile induced by VEGF. The expression of VEGF and KDR correlates highly with the normal ocular vascularization in humans. The expression of vascular endothelial growth factor and its receptors KDR and Flt-1 by gastric carcinoma tissues and cell lines was detected to elucidate the molecular mechanism of this growth factor in promoting tumor growth. The majority of embryonic stem cells with the potential to differentiate into osteoclasts expressed Flk-1. These data indicate that activation of vascular endothelial growth factor receptor-2 prevents endothelial cell apoptosis by inhibiting p38 MAP kinase phosphorylation and reducing caspase-3 activity. These data support the involvement in melanoma growth and survival of a VEGF-dependent internal autocrine loop mechanism, at least in vitro. Up-regulation of VEGF-A receptor VEGFR-2 in capillaries in menorrhagia could be involved in abnormal endometrial vascular structure and permeability. VEGF and its receptor, KDR, genes contributed to the development of coronary artery lesions in Kawasaki disease patients. VEGF receotor signaling regulates survival signals in CLL cells and that interruption of this autocrine pathway results in caspase activation and subsequent leukemic cell death. VEGF(165)-induced phosphorylation of KDR and PLCgamma was partially inhibited by PF-4. VEGF, VEGFR-1 and VEGFR-2 are concomitantly expressed in pre-B ALL cells. Expression of the receptors is limited to the intra-cytoplasmic compartment and may suggest either internalization or a block in trafficking of the receptor to the surface. VEGFR-2 expression, co-localized in the cytoplasmic and nuclear membrane, is associated with progression towards invasive melanoma. VEGFR-2 has a role in regulating angiogenesis-related functions [review]. VEGFR-3 needs to be associated to VEGFR-2 to induce ligand-dependent cellular responses. VEGFR2 initiates a clonogenic response in myeloid leukemia cells that is PI3-kinase dependent. VEGFR2 may be involved in the transcriptional regulation of T-cell lymphoma. VEGFR2 mediated phosphorylation of focal adhesion kinase is regulated by heat shock protein 90 and Src kinase activities. Activation of the P2Y(2)R induced rapid tyrosine phosphorylation of vascular endothelial growth factor receptor (VEGFR)-2 in human coronary artery endothelial cells. Assessed the role of VEGF and its receptors in osteoclastogenesis, in vitro, by culturing osteoclast precursors in the presence of VEGF, VEGF receptor-specific ligands, and blocking antibodies to VEGF receptors. Changing of transcriptional activity of VEGF gene and its receptor FLK-1 indicates an autocrine mechanism of regulation of angiogenic gene activity in the first step of carcinogenesis--low-grade intraepithelial lesions of the uterine cervix. Decrease in expression is caused by C-reactive protein. Findings implicate altered VEGF and KDR signaling in pituitary tumorigenesis; PTTG stimulation of FGF-2 and VEGF expression in the presence of up-regulated growth factor receptors may account for angiogenic growth and progression of human pituitary tumors. Green tea catechins are novel inhibitors of VEGFR-2 activity. Human VEGFR-2 promoter is functionally counter-regulated by TFII-I and TFII-IRD1. In humans: 1) VEGF, KDR, and Flt-1 mRNA are increased by acute systemic exercise; 2) the time course of the VEGF, KDR, and Flt-1 mRNA responses are different from those previously reported in rats. Maximal P-selectin translocation and subsequent neutrophil adhesion was mediated by VEGF-A(165) on the activation of VEGFR-2/NRP-1 complex and required PAF synthesis. Phosphorylation of Y1214 on VEGFR2 is required to trigger the sequential activation of Cdc42 and SAPK2/p38 and to drive the SAPK2/p38-mediated actin remodeling in stress fibers in endothelial cells exposed to VEGF. Regulatory mechanisms involved in the attenuation of VEGFR-2 activation is mediated by nonclassical Protein Kinase C and the presence of serine sites in the carboxyl terminal of VEGFR-2. Role in modulating tumor neovascularization in conjunction with interleukin-3 receptor. The level of sVEGFR-2 is lower in active systemic lupus erythematosus than in inactive disease. There was no significant correlation between VEGF and VEGF-R2 expression. VEGF-R2 expression was significantly increased on endothelial cell (. Transcriptional activation of Flk-1 in endothelial cells requires the interaction between HIF-2alpha and Ets-1. Vascular endothelial growth factor (VEGF) is strongly expressed in villous cytotrophoblast cells and subsequently in Hofbauer cells while its receptors Flt-1 and Flk-1 are found on vasculogenic and angiogenic precursor cells. Vitronectin increased the presence of all four growth factor receptors and most notably, VEGFR-1; in contrast, fibrin decreased all four receptors, especially FGFR-1 and FGFR-2.
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