Project description:The project concerns vascular endothelial growth factor (VEGF) signaling, which is dependent on binding of VEGF to VEGF receptor-2 (VEGFR2) and leads to activation of the receptor kinase and autophosphorylation. Previous mouse studies with the VEGFR-2 phosphorylation site mutation Y1212F showed reduced vascular stability. We here investigate with LC-MS proteomics which signal transduction pathway(s) are lost in the mutant by identifying proteins that bind to the Y1212F site.
Project description:MicroRNA expression profiling of human microvascular endothelial cells (HMVECs) treated with either vascular endothelial growth factor (VEGF) only or in combination with the natural angiogenesis inhibitor pigment epithelial-derived factor (PEDF). Originally we were interested in the microRNA-mediated regulation of angiogenesis by the endogenous anti-angiogenic PEDF. To identify the microRNAs involved in PEDF signaling in activated endothelial cells, we compared the levels of microRNAs in non-treated microvascular endothelial cells, cells treated with VEGF, and cells treated with a combination of VEGF and PEDF. After treatment, total RNA content was isolated and sent for analysis to LC Sciences, LLC. They performed expression profiling and completed statistical analysis, based on which we confirmed the regulation of one of the microRNAs, mir-27b. In the following experiments, we identified the targets of mir-27b relevant for angiogenesis and confirmed our findings in zebrafish and mouse models. The manuscript describes the key role of mir-27b in determination of the endothelial tip cell fate and venous differentiation by regulating Notch ligand Delta-like ligand 4 (Dll4) and Sprouty homologue 2 (Spry2). Three-condition experiment: untreated (control) HMVECs vs. VEGF-treated HMVECs vs. PEDF/VEGF-treated HMVECs.
Project description:to study the relationship between angiotensinogen gene (AGT) and vascular endothelial growth factor gene (VEGF) single nucleotide polymorphisms and susceptibility to bladder and kidney cancer.
Project description:Numerous studies have suggested a link between fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) signaling pathways; however the nature of this link has not been established. To evaluate this relationship we investigated VEGF signaling in endothelial cells with disrupted FGF signaling in vitro and in vivo. We find that endothelial cells lacking FGF signaling become unresponsive to VEGF due to down regulation of VEGFR2 expression caused by reduced Vegfr2 enhancer activation, which is in turn caused by reduced activation of Ets family transcription factors. In vivo this manifests in the loss of vascular integrity and morphogenesis. Thus, basal FGF stimulation of the endothelium is required for maintenance of VEGFR2 expression and the ability to respond to VEGF stimulation and accounts for the hierarchic control of vascular formation by FGFs and VEGF. Primary mouse lung endothelial cells were transduced with either Adeno-Null (empty) or Adeno- dominant negative FGF receptor 1 and harvested 24 hours after transduction. Total RNA was extracted and subjected to the analysis using SuperArray GEArray Q Series Mouse Angiogenesis Gene Array. Comparisons were made between treatments.
Project description:Angiogenesis-inhibitor (AI) drugs targeting vascular endothelial growth factor (VEGF) signalling to the endothelial cell (EC) are used to treat various cancers types. However, primary or secondary resistance to therapy is common. Clinical and pre-clinical studies suggest that other alternative pro-angiogenic factors are up-regulated after VEGF-pathway inhibition. Therefore, identification alternative pro-angiogenic pathway(s) is critical for the development of more effective anti-angiogenic therapy. Here we study the role of apelin as a pro-angiogenic G-protein coupled receptor (GPCR) ligand in tumor growth and angiogenesis. We applied single-cell RNA-sequencing to Mouse Lewis lung carcinoma (LLC1) or B16F10 mouse melanoma cell lines (1 X 106) implanted subcutaneously into the flanks of 12 weeks old Apln-/y or littermate control mice in combination with sunitinib or control (vehicle) treatment. We found apelin loss reduced angiogenic sprouting and tip cell marker gene expression in comparison to the sunitinib-alone treated mice and prevented EC tip cell differentiation.
Project description:Human microvascular endothelial cells (HMVEC) treated with vascular endothelial growth factor (VEGF), Antrhax Edema Toxin (ET), or the Epac activator, 8-pCPT-2'-O-Me-cAMP (8CPT); Human microvascular endothelial cells (HMVEC) were treated with VEGF alone or VEGF in combination with either the the Epac-specific cAMP-mimetic, 8-pCPT-2'-O-Me-cAMP (8CPT), or anthrax edema toxin (ET), an adenylyl cyclase. ET or 8CPT can inhibit VEGF-mediated chemotaxis and angiogenesis. The goal of the study was to identify genes regulated by cAMP production (ET) or by activation of Epac/Rap (8CPT) that may mitigate the effects of VEGF treatment. Experiment Overall Design: Gene expression was measured 4 hours after treatment with VEGF, VEGF + 8CPT, VEGF + ET or mock treatment. Each sample contained one replicate.
Project description:HUVECs (human umbilical cord vein endothelial cells) are treated with the angiogenic factors VEGF-A (vascular endothelial growth factor-A) and PlGF (placental growth factor) in low or high serum media.
Project description:The standard treatment for neovascular age-related macular degeneration (nAMD) consists of intravitreal anti-vascular endothelial growth factors (VEGF). However, for some patients, even maximal anti-VEGF treatment does notentirely suppress exudative activity. The goal of this study was to identify molecular biomarkers in nAMD with incomplete response to anti-VEGF treatment. Aqueous humor (AH) samples were collected from three groups of patients: 18 patients with nAMD responding incompletely to anti-VEGF, 19 patients affected by nAMD with normal treatment response, and 14 control patients without any retinopathy. Proteomic and multiplex analyses were performed on these samples. Proteomic analyses showed that nAMD patients with incomplete anti-VEGF response displayed an increased inflammatory response, complement activation, cytolysis, protein-lipid complex, and vasculature development pathways. Multiplex analyses revealed a significant increase of soluble vascular cell adhesion molecule-1 (sVCAM-1) [p=0.001], interleukin-6 (IL-6) [p=0.009], bioactive interleukin-12 (IL-12p40) [p=0.03], plasminogen activator inhibitor type 1 (PAI-1) [p=0.004], and hepatocyte growth factor (HGF)[p=0.004] levels in incomplete responders in comparison to normal treatment response. Interestingly, The same biomarkers showed a high intercorrelation with r2 values between 0.58 and 0.94. In addition, we confirmed by AlphaLISA the increase of sVCAM-1 [p<0.0001] and IL-6 [p=0.043] in incomplete responder group. Incomplete responders in nAMD are associated with activated angiogenic and inflammatory pathways. The residual exudative activity of nAMD despite maximal anti-VEGF treatment may be related to both angiogenic and inflammatory responses requiring specific adjuvant therapy.