scholarly journals Angiogenic factor signaling regulates centrosome duplication in endothelial cells of developing blood vessels

Blood ◽  
2010 ◽  
Vol 116 (16) ◽  
pp. 3108-3117 ◽  
Author(s):  
Sarah M. Taylor ◽  
Kathleen R. Nevis ◽  
Hannah L. Park ◽  
Gregory C. Rogers ◽  
Stephen L. Rogers ◽  
...  

Abstract Regulated vascular endothelial growth factor (VEGF) signaling is required for proper angiogenesis, and excess VEGF signaling results in aberrantly formed vessels that do not function properly. Tumor endothelial cells have excess centrosomes and are aneuploid, properties that probably contribute to the morphologic and functional abnormalities of tumor vessels. We hypothesized that endothelial cell centrosome number is regulated by signaling via angiogenic factors, such as VEGF. We found that endothelial cells in developing vessels exposed to elevated VEGF signaling display centrosome overduplication. Signaling from VEGF, through either MEK/ERK or AKT to cyclin E/Cdk2, is amplified in association with centrosome overduplication, and blockade of relevant pathway components rescued the centrosome overduplication defect. Endothelial cells exposed to elevated FGF also had excess centrosomes, suggesting that multiple angiogenic factors regulate centrosome number. Endothelial cells with excess centrosomes survived and formed aberrant spindles at mitosis. Developing vessels exposed to elevated VEGF signaling also exhibited increased aneuploidy of endothelial cells, which is associated with cellular dysfunction. These results provide the first link between VEGF signaling and regulation of the centrosome duplication cycle, and suggest that endothelial cell centrosome overduplication contributes to aberrant angiogenesis in developing vessel networks exposed to excess angiogenic factors.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kang-Moon Song ◽  
Woo Jean Kim ◽  
Min-Ji Choi ◽  
Ki-Dong Kwon ◽  
Anita Limanjaya ◽  
...  

AbstractNeovascularization of the erectile tissue emerges as a beneficial curative approach to treat erectile dysfunction (ED). Here we for the first time report the unexpected role of vasohibin-1 (VASH1), mainly known as an anti-angiogenic factor, in restoring erectile function in diabetic mice. A diabetic patient has lower cavernous VASH1 expression than in the potent man. VASH1 was mainly expressed in endothelial cells. There were significant decreases in cavernous endothelial cell and pericyte contents in VASH1 knockout mice compared with those in wild-type mice, which resulted in impairments in erectile function. Intracavernous injection of VASH1 protein successfully restored erectile function in the diabetic mice (~ 90% of control values). VASH1 protein reinstated endothelial cells, pericytes, and endothelial cell–cell junction proteins and induced phosphorylation of eNOS (Ser1177) in the diabetic mice. The induction of angiogenic factors, such as angiopoietin-1 and vascular endothelial growth factor, is responsible for cavernous angiogenesis and the restoration of erectile function mediated by VASH1. Altogether, these findings suggest that VASH1 is proangiogenic in diabetic penis and is a new potential target for diabetic ED.


2001 ◽  
Vol 168 (3) ◽  
pp. 409-416 ◽  
Author(s):  
SE Dickson ◽  
R Bicknell ◽  
HM Fraser

Vascular endothelial growth factor (VEGF) is essential for the angiogenesis required for the formation of the corpus luteum; however, its role in ongoing luteal angiogenesis and in the maintenance of the established vascular network is unknown. The aim of this study was to determine whether VEGF inhibition could intervene in ongoing luteal angiogenesis using immunoneutralisation of VEGF starting in the mid-luteal phase. In addition, the effects on endothelial cell survival and the recruitment of periendothelial support cells were examined. Treatment with a monoclonal antibody to VEGF, or mouse gamma globulin for control animals, commenced on day 7 after ovulation and continued for 3 days. Bromodeoxyuridine (BrdU), used to label proliferating cells to obtain a proliferation index, was administered one hour before collecting ovaries from control and treated animals. Ovarian sections were stained using antibodies to BrdU, the endothelial cell marker, CD31, the pericyte marker, alpha-smooth muscle actin, and 3' end DNA fragments as a marker for apoptosis. VEGF immunoneutralisation significantly suppressed endothelial cell proliferation and the area occupied by endothelial cells while increasing pericyte coverage and the incidence of endothelial cell apoptosis. Luteal function was markedly compromised by anti-VEGF treatment as judged by a 50% reduction in plasma progesterone concentration. It is concluded that ongoing angiogenesis in the mid-luteal phase is primarily driven by VEGF, and that a proportion of endothelial cells of the mid-luteal phase vasculature are dependent on VEGF support.


2005 ◽  
Vol 16 (2) ◽  
pp. 609-625 ◽  
Author(s):  
Allan R. Albig ◽  
William P. Schiemann

Tubulogenesis by epithelial cells regulates kidney, lung, and mammary development, whereas that by endothelial cells regulates vascular development. Although functionally dissimilar, the processes necessary for tubulation by epithelial and endothelial cells are very similar. We performed microarray analysis to further our understanding of tubulogenesis and observed a robust induction of regulator of G protein signaling 4 (RGS4) mRNA expression solely in tubulating cells, thereby implicating RGS4 as a potential regulator of tubulogenesis. Accordingly, RGS4 overexpression delayed and altered lung epithelial cell tubulation by selectively inhibiting G protein-mediated p38 MAPK activation, and, consequently, by reducing epithelial cell proliferation, migration, and expression of vascular endothelial growth factor (VEGF). The tubulogenic defects imparted by RGS4 in epithelial cells, including its reduction in VEGF expression, were rescued by overexpression of constitutively active MKK6, an activator of p38 MAPK. Similarly, RGS4 overexpression abrogated endothelial cell angiogenic sprouting by inhibiting their synthesis of DNA and invasion through synthetic basement membranes. We further show that RGS4 expression antagonized VEGF stimulation of DNA synthesis and extracellular signal-regulated kinase (ERK)1/ERK2 and p38 MAPK activation as well as ERK1/ERK2 activation stimulated by endothelin-1 and angiotensin II. RGS4 had no effect on the phosphorylation of Smad1 and Smad2 by bone morphogenic protein-7 and transforming growth factor-β, respectively, indicating that RGS4 selectively inhibits G protein and VEGF signaling in endothelial cells. Finally, we found that RGS4 reduced endothelial cell response to VEGF by decreasing VEGF receptor-2 (KDR) expression. We therefore propose RGS4 as a novel antagonist of epithelial and endothelial cell tubulogenesis that selectively antagonizes intracellular signaling by G proteins and VEGF, thereby inhibiting cell proliferation, migration, and invasion, and VEGF and KDR expression.


2018 ◽  
Vol 11 (552) ◽  
pp. eaau1165 ◽  
Author(s):  
Ameer L. Elaimy ◽  
Arthur M. Mercurio

Vascular endothelial growth factor (VEGF) stimulates endothelial cells to promote both developmental and pathological angiogenesis. VEGF also directly affects tumor cells and is associated with the initiation, progression, and recurrence of tumors, as well as the emergence and maintenance of cancer stem cells (CSCs). Studies have uncovered the importance of the transcriptional regulators YAP and TAZ in mediating VEGF signaling. For example, VEGF stimulates the GTPase activity of Rho family members and thereby alters cytoskeletal dynamics, which contributes to the activation of YAP and TAZ. In turn, YAP- and TAZ-mediated changes in gene expression sustain Rho family member activity and cytoskeletal effects to promote both vascular growth and remodeling in endothelial cells and the acquisition of stem-like traits in tumor cells. In this Review, we discuss how these findings further explain the pathophysiological roles of VEGF and YAP/TAZ, identify their connections to other receptor-mediated pathways, and reveal ways of therapeutically targeting their convergent signals in patients.


2010 ◽  
Vol 84 (21) ◽  
pp. 11227-11234 ◽  
Author(s):  
Punya Shrivastava-Ranjan ◽  
Pierre E. Rollin ◽  
Christina F. Spiropoulou

ABSTRACT Hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS) are severe diseases associated with hantavirus infection. High levels of virus replication occur in microvascular endothelial cells but without a virus-induced cytopathic effect. However, virus infection results in microvascular leakage, which is the hallmark of these diseases. VE-cadherin is a major component of adherens junctions, and its interaction with the vascular endothelial growth factor (VEGF) receptor, VEGF-R2, is important for maintaining the integrity of the endothelial barrier. Here we report that increased secreted VEGF and concomitant decreased VE-cadherin are seen at early times postinfection of human primary lung endothelial cells with an HPS-associated hantavirus, Andes virus. Furthermore, active virus replication results in increased permeability and loss of the integrity of the endothelial cell barrier. VEGF binding to VEGF-R2 is known to result in dissociation of VEGF-R2 from VE-cadherin and in VE-cadherin activation, internalization, and degradation. Consistent with this, we showed that an antibody which blocks VEGF-R2 activation resulted in inhibition of the Andes virus-induced VE-cadherin reduction. These data implicate virus induction of VEGF and reduction in VE-cadherin in the endothelial cell permeability seen in HPS and suggest potential immunotherapeutic targets for the treatment of the disease.


Blood ◽  
2000 ◽  
Vol 95 (6) ◽  
pp. 1979-1987 ◽  
Author(s):  
Victoria L. Bautch ◽  
Sambra D. Redick ◽  
Aaron Scalia ◽  
Marco Harmaty ◽  
Peter Carmeliet ◽  
...  

Abstract Vascular endothelial growth factor (VEGF) signaling is required for both differentiation and proliferation of vascular endothelium. Analysis of differentiated embryonic stem cells with one or both VEGF-A alleles deleted showed that both the differentiation and the expansion of endothelial cells are blocked during vasculogenesis. Blood island formation was reduced by half in hemizygous mutant VEGF cultures and by 10-fold in homozygous mutant VEGF cultures. Homozygous mutant cultures could be partially rescued by the addition of exogenous VEGF. RNA levels for the endothelial adhesion receptors ICAM-2 and PECAM were reduced in homozygous mutant cultures, but ICAM-2 RNA levels decreased substantially, whereas PECAM RNA levels remained at hemizygous levels. The quantitative data correlated with the antibody staining patterns because cells that were not organized into vessels expressed PECAM but not ICAM-2. These PECAM+ cell clumps accumulated in mutant cultures as vessel density decreased, suggesting that they were endothelial cell precursors blocked from maturation. A subset of PECAM+ cells in clumps expressed stage-specific embryonic antigen-1 (SSEA-1), and all were ICAM-2(−) and CD34(−), whereas vascular endothelial cells incorporated into vessels were PECAM(+), ICAM-2(+), CD34(+), and SSEA-1(−). Analysis of flk-1 expression indicated that a subset of vascular precursor cells coexpressed PECAM and flk-1. These data suggest that VEGF signaling acts in a dose-dependent manner to affect both a specific differentiation step and the subsequent expansion of endothelial cells.


2008 ◽  
Vol 205 (12) ◽  
pp. 2929-2945 ◽  
Author(s):  
Astrid F. Nottebaum ◽  
Giuseppe Cagna ◽  
Mark Winderlich ◽  
Alexander C. Gamp ◽  
Ruth Linnepe ◽  
...  

We have shown recently that vascular endothelial protein tyrosine phosphatase (VE-PTP), an endothelial-specific membrane protein, associates with vascular endothelial (VE)–cadherin and enhances VE-cadherin function in transfected cells (Nawroth, R., G. Poell, A. Ranft, U. Samulowitz, G. Fachinger, M. Golding, D.T. Shima, U. Deutsch, and D. Vestweber. 2002. EMBO J. 21:4885–4895). We show that VE-PTP is indeed required for endothelial cell contact integrity, because down-regulation of its expression enhanced endothelial cell permeability, augmented leukocyte transmigration, and inhibited VE-cadherin–mediated adhesion. Binding of neutrophils as well as lymphocytes to endothelial cells triggered rapid (5 min) dissociation of VE-PTP from VE-cadherin. This dissociation was only seen with tumor necrosis factor α–activated, but not resting, endothelial cells. Besides leukocytes, vascular endothelial growth factor also rapidly dissociated VE-PTP from VE-cadherin, indicative of a more general role of VE-PTP in the regulation of endothelial cell contacts. Dissociation of VE-PTP and VE-cadherin in endothelial cells was accompanied by tyrosine phoshorylation of VE-cadherin, β-catenin, and plakoglobin. Surprisingly, only plakoglobin but not β-catenin was necessary for VE-PTP to support VE-cadherin adhesion in endothelial cells. In addition, inhibiting the expression of VE-PTP preferentially increased tyrosine phosphorylation of plakoglobin but not β-catenin. In conclusion, leukocytes interacting with endothelial cells rapidly dissociate VE-PTP from VE-cadherin, weakening endothelial cell contacts via a mechanism that requires plakoglobin but not β-catenin.


Endocrinology ◽  
2008 ◽  
Vol 149 (12) ◽  
pp. 6076-6083 ◽  
Author(s):  
Graham W. Aberdeen ◽  
Stanley J. Wiegand ◽  
Thomas W. Bonagura ◽  
Gerald J. Pepe ◽  
Eugene D. Albrecht

To assess whether there is a link between estrogen, vascular endothelial growth factor (VEGF), and early aspects of uterine angiogenesis, an acute temporal study was conducted in which ovariectomized baboons were pretreated with VEGF Trap, which sequesters endogenous VEGF, and administered estradiol at time 0 h. Serum estradiol levels approximated 500 pg/ml 4–6 h after estradiol administration. VEGF mRNA levels in endometrial glandular epithelial and stromal cells were increased to values 6 h after estradiol that were 3.74 ± 0.99-fold (mean ± se) and 5.70 ± 1.60-fold greater (P < 0.05), respectively, than at 0 h. Microvessel interendothelial cell tight junctions, which control paracellular permeability, were present in the endometrium at time 0 h, but not evident 6 h after estradiol administration. Thus, microvessel paracellular cleft width increased (P < 0.01, ANOVA) from 5.03 ± 0.22 nm at 0 h to 7.27 ± 0.48 nm 6 h after estrogen. In contrast, tight junctions remained intact, and paracellular cleft widths were unaltered in estradiol/VEGF Trap and vehicle-treated animals. Endometrial microvessel endothelial cell mitosis, i.e. percent Ki67+/Ki67− immunolabeled endothelial cells, increased (P < 0.05) from 2.9 ± 0.3% at 0 h to 21.4 ± 7.0% 6 h after estrogen treatment but was unchanged in estradiol/VEGF Trap and vehicle-treated animals. In summary, the estrogen-induced disruption of endometrial microvessel endothelial tight junctions and increase in endothelial cell proliferation were prevented by VEGF Trap. Therefore, we propose that VEGF mediates the estrogen-induced increase in microvessel permeability and endothelial cell proliferation as early steps in angiogenesis in the primate endometrium.


2008 ◽  
Vol 87 (12) ◽  
pp. 1166-1171 ◽  
Author(s):  
M. Miyazawa ◽  
Z. Dong ◽  
Z. Zhang ◽  
K.G. Neiva ◽  
M.M. Cordeiro ◽  
...  

Transformation of small avascular masses of tumor cells into rapidly progressive cancers is triggered by the angiogenic switch, a process that involves vascular endothelial growth factor (VEGF) signaling. We have shown that VEGF enhances the survival and angiogenic potential of endothelial cells by activating the Bcl-2-CXCL8 signaling axis. The purpose of this study was to evaluate the effect of a small-molecule inhibitor of VEGF receptors (PTK/ZK) on the initial stages of head and neck tumor angiogenesis. In vitro, PTK/ZK blocked head and neck tumor cell (OSCC3 or UM-SCC-17B)-induced Bcl-2 and CXCL8 expression in endothelial cells. Oral administration of PTK/ZK decreased xenograft head and neck tumor microvessel density, and inhibited Bcl-2 and CXCL8 expression in tumor-associated endothelial cells. Analysis of these data demonstrates that PTK/ZK blocks downstream targets of VEGF signaling in endothelial cells, and suggests that PTK/ZK may inhibit the angiogenic switch in head and neck tumors. Abbreviations: HDMEC, human dermal microvascular endothelial cells; VEGF, vascular endothelial growth factor; CXCL8, CXC ligand-8; PTK/ZK, PTK787/ZK222584.


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