scholarly journals Tyrosine phosphorylation of DEP-1/CD148 as a mechanism controlling Src kinase activation, endothelial cell permeability, invasion, and capillary formation

Blood ◽  
2012 ◽  
Vol 120 (13) ◽  
pp. 2745-2756 ◽  
Author(s):  
Kathleen Spring ◽  
Catherine Chabot ◽  
Simon Langlois ◽  
Line Lapointe ◽  
Nguyen Thu Ngan Trinh ◽  
...  

Abstract DEP-1/CD148 is a receptor-like protein tyrosine phosphatase with antiproliferative and tumor-suppressive functions. Interestingly, it also positively regulates Src family kinases in hematopoietic and endothelial cells, where we showed it promotes VE-cadherin–associated Src activation and endothelial cell survival upon VEGF stimulation. However, the molecular mechanism involved and its biologic functions in endothelial cells remain ill-defined. We demonstrate here that DEP-1 is phosphorylated in a Src- and Fyn-dependent manner on Y1311 and Y1320, which bind the Src SH2 domain. This allows DEP-1–catalyzed dephosphorylation of Src inhibitory Y529 and favors the VEGF-induced phosphorylation of Src substrates VE-cadherin and Cortactin. Accordingly, RNA interference (RNAi)–mediated knockdown of DEP-1 or expression of DEP-1 Y1311F/Y1320F impairs Src-dependent biologic responses mediated by VEGF including permeability, invasion, and branching capillary formation. In addition, our work further reveals that above a threshold expression level, DEP-1 can also dephosphorylate Src Y418 and attenuate downstream signaling and biologic responses, consistent with the quiescent behavior of confluent endothelial cells that express the highest levels of endogenous DEP-1. Collectively, our findings identify the VEGF-dependent phosphorylation of DEP-1 as a novel mechanism controlling Src activation, and show this is essential for the proper regulation of permeability and the promotion of the angiogenic response.

2021 ◽  
Vol 11 ◽  
Author(s):  
Romain Sigaud ◽  
Nadège Dussault ◽  
Caroline Berenguer-Daizé ◽  
Christine Vellutini ◽  
Zohra Benyahia ◽  
...  

VE-cadherin is an essential adhesion molecule in endothelial adherens junctions, and the integrity of these complexes is thought to be regulated by VE-cadherin tyrosine phosphorylation. We have previously shown that adrenomedullin (AM) blockade correlates with elevated levels of phosphorylated VE-cadherin (pVE-cadherinY731) in endothelial cells, associated with impaired barrier function and a persistent increase in vascular endothelial cell permeability. However, the mechanism underlying this effect is unknown. In this article, we demonstrate that the AM-mediated dephosphorylation of pVE-cadherinY731 takes place through activation of the tyrosine phosphatase SHP-2, as judged by the rise of its active fraction phosphorylated at tyrosine 542 (pSHP-2Y542) in HUVECs and glioblastoma-derived-endothelial cells. Both pre-incubation of HUVECs with SHP-2 inhibitors NSC-87877 and SHP099 and SHP-2 silencing hindered AM-induced dephosphorylation of pVE-cadherinY731 in a dose dependent-manner, showing the role of SHP-2 in the regulation of endothelial cell contacts. Furthermore, SHP-2 inhibition impaired AM-induced HUVECs differentiation into cord-like structures in vitro and impeded AM-induced neovascularization in in vivo Matrigel plugs bioassays. Subcutaneously transplanted U87-glioma tumor xenograft mice treated with AM-receptors-blocking antibodies showed a decrease in pSHP-2Y542 associated with VE-cadherin in nascent tumor vasculature when compared to control IgG-treated xenografts.Our findings show that AM acts on VE-cadherin dynamics through pSHP-2Y542 to finally modulate cell-cell junctions in the angiogenesis process, thereby promoting a stable and functional tumor vasculature.


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.


1998 ◽  
Vol 275 (2) ◽  
pp. L203-L222 ◽  
Author(s):  
Timothy M. Moore ◽  
Paul M. Chetham ◽  
John J. Kelly ◽  
Troy Stevens

Pulmonary endothelium forms a semiselective barrier that regulates fluid balance and leukocyte trafficking. During the course of lung inflammation, neurohumoral mediators and oxidants act on endothelial cells to induce intercellular gaps permissive for transudation of proteinaceous fluid from blood into the interstitium. Intracellular signals activated by neurohumoral mediators and oxidants that evoke intercellular gap formation are incompletely understood. Cytosolic Ca2+ concentration ([Ca2+]i) and cAMP are two signals that importantly dictate cell-cell apposition. Although increased [Ca2+]ipromotes disruption of the macrovascular endothelial cell barrier, increased cAMP enhances endothelial barrier function. Furthermore, during the course of inflammation, elevated endothelial cell [Ca2+]idecreases cAMP to facilitate intercellular gap formation. Given the significance of both [Ca2+]iand cAMP in mediating cell-cell apposition, this review addresses potential sites of cross talk between these two intracellular signaling pathways. Emerging data also indicate that endothelial cells derived from different vascular sites within the pulmonary circulation exhibit distinct sensitivities to permeability-inducing stimuli; that is, elevated [Ca2+]ipromotes macrovascular but not microvascular barrier disruption. Thus this review also considers the roles of [Ca2+]iand cAMP in mediating site-specific alterations in endothelial permeability.


2008 ◽  
Vol 294 (1) ◽  
pp. R266-R275 ◽  
Author(s):  
Shigenobu Matsumura ◽  
Tetsuro Shibakusa ◽  
Teppei Fujikawa ◽  
Hiroyuki Yamada ◽  
Kiyoshi Matsumura ◽  
...  

Transforming growth factor-β (TGF-β), a pleiotropic cytokine, regulates cell proliferation, differentiation, and apoptosis, and plays a key role in development and tissue homeostasis. TGF-β functions as an anti-inflammatory cytokine because it suppresses microglia and B-lymphocyte functions, as well as the production of proinflammatory cytokines. However, we previously demonstrated that the intracisternal administration of TGF-β induces fever like that produced by proinflammatory cytokines. In this study, we investigated the mechanism of TGF-β-induced fever. The intracisternal administration of TGF-β increased body temperature in a dose-dependent manner. Pretreatment with cyclooxygenase-2 (COX-2)-selective inhibitor significantly suppressed TGF-β-induced fever. COX-2 is known as one of the rate-limiting enzymes of the PGE2 synthesis pathway, suggesting that fever induced by TGF-β is COX-2 and PGE2 dependent. TGF-β increased PGE2 levels in cerebrospinal fluid and increased the expression of COX-2 in the brain. Double immunostaining of COX-2 and von Willebrand factor (vWF, an endothelial cell marker) revealed that COX-2-expressing cells were mainly endothelial cells. Although not all COX-2-immunoreactive cells express TGF-β receptor, some COX-2-immunoreactive cells express activin receptor-like kinase-1 (ALK-1, an endothelial cell-specific TGF-β receptor), suggesting that TGF-β directly or indirectly acts on endothelial cells to induce COX-2 expression. These findings suggest a novel function of TGF-β as a proinflammatory cytokine in the central nervous system.


2001 ◽  
Vol 12 (1) ◽  
pp. 85-100 ◽  
Author(s):  
Meredith Gonzales ◽  
Babette Weksler ◽  
Daisuke Tsuruta ◽  
Robert D. Goldman ◽  
Kristine J. Yoon ◽  
...  

The α4 laminin subunit is a component of endothelial cell basement membranes. An antibody (2A3) against the α4 laminin G domain stains focal contact-like structures in transformed and primary microvascular endothelial cells (TrHBMECs and HMVECs, respectively), provided the latter cells are activated with growth factors. The 2A3 antibody staining colocalizes with that generated by αv and β3 integrin antibodies and, consistent with this localization, TrHBMECs and HMVECs adhere to the α4 laminin subunit G domain in an αvβ3-integrin–dependent manner. The αvβ3 integrin/2A3 antibody positively stained focal contacts are recognized by vinculin antibodies as well as by antibodies against plectin. Unusually, vimentin intermediate filaments, in addition to microfilament bundles, interact with many of the αvβ3 integrin-positive focal contacts. We have investigated the function of α4-laminin and αvβ3-integrin, which are at the core of these focal contacts, in cultured endothelial cells. Antibodies against these proteins inhibit branching morphogenesis of TrHBMECs and HMVECs in vitro, as well as their ability to repopulate in vitro wounds. Thus, we have characterized an endothelial cell matrix adhesion, which shows complex cytoskeletal interactions and whose assembly is regulated by growth factors. Our data indicate that this adhesion structure may play a role in angiogenesis.


2012 ◽  
Vol 302 (7) ◽  
pp. F884-F894 ◽  
Author(s):  
Nidia Maritza Hernandez ◽  
Anna Casselbrant ◽  
Meghnad Joshi ◽  
Bengt R. Johansson ◽  
Suchitra Sumitran-Holgersson

Anti-endothelial cell antibodies (AECA) have been reported to cause endothelial dysfunction, but their clinical importance for tissue-specific endothelial cells is not clear. We hypothesized that AECA reactive with human kidney endothelial cells (HKEC) may cause renal endothelial dysfunction in patients with chronic kidney diseases. We report that a higher fraction (56%) of end-stage renal disease (ESRD) patients than healthy controls (5%) have AECA reactive against kidney endothelial cells ( P <0.001). The presence of antibodies was associated with female gender ( P < 0.001), systolic hypertension ( P < 0.01), and elevated TNF-α ( P < 0.05). These antibodies markedly decrease expression of both adherens and tight junction proteins VE-cadherin, claudin-1, and zonula occludens-1 and provoked a rapid increase in cytosolic free Ca2+and rearrangement of actin filaments in HKEC compared with controls. This was followed by an enhancement in protein flux and phosphorylation of VE-cadherin, events associated with augmented endothelial cell permeability. Additionally, kidney biopsies from ESRD patients with AECA but not controls demonstrated a marked decrease in adherens and tight junctions in glomerular endothelium, confirming our in vitro data. In summary, our data demonstrate a causal link between AECA and their capacity to induce alterations in glomerular vascular permeability.


2017 ◽  
Vol 37 (12) ◽  
Author(s):  
Ying Zhang ◽  
Rony Chidiac ◽  
Chantal Delisle ◽  
Jean-Philippe Gratton

ABSTRACT Nitric oxide (NO) produced by endothelial NO synthase (eNOS) modulates many functions in endothelial cells. S-nitrosylation (SNO) of cysteine residues on β-catenin by eNOS-derived NO has been shown to influence intercellular contacts between endothelial cells. However, the implication of SNO in the regulation of β-catenin transcriptional activity is ill defined. Here, we report that NO inhibits the transcriptional activity of β-catenin and endothelial cell proliferation induced by activation of Wnt/β-catenin signaling. Interestingly, induction by Wnt3a of β-catenin target genes, such as the axin2 gene, is repressed in an eNOS-dependent manner by vascular endothelial growth factor (VEGF). We identified Cys466 of β-catenin as a target for SNO by eNOS-derived NO and as the critical residue for the repressive effects of NO on β-catenin transcriptional activity. Furthermore, we observed that Cys466 of β-catenin, located at the binding interface of the β-catenin–TCF4 transcriptional complex, is essential for disruption of this complex by NO. Importantly, Cys466 of β-catenin is necessary for the inhibitory effects of NO on Wnt3a-stimulated proliferation of endothelial cells. Thus, our data define the mechanism responsible for the repressive effects of NO on the transcriptional activity of β-catenin and link eNOS-derived NO to the modulation by VEGF of Wnt/β-catenin-induced endothelial cell proliferation.


2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Jennifer S Esser ◽  
Susanne Rahner ◽  
Meike Deckler ◽  
Christoph Bode ◽  
Martin Moser

Introduction: Bone morphogenetic proteins (BMP) play a key role in vascular development. Previously, we have identified BMP endothelial cell precursor-derived regulator (BMPER), an extracellular BMP modulator, to increase the angiogenic activity of endothelial cells in a concentration-dependent manner. In this project we now investigate how the BMPER effect is mediated by key molecules of angiogenesis. Methods and Results: To assess the effect of BMPER on angiogenesis-related molecules we performed an angiogenesis antibody array with BMPER-stimulated human umbilical venous endothelial cells (HUVECs) and vice versa with BMPER-silenced HUVECs compared to control conditions, respectively. We detected increased protein expression of the anti-angiogenic thrombospondin-1 (TSP-1) 48 hours after siBMPER transfection and, consistently, decreased TSP-1 expression after stimulation with BMPER (60 ng/ml; 39% ± 7.3 N=4). Furthermore, the pro-angiogenic protein bFGF was increased after BMPER stimulation, which was confirmed by realtime-PCR and western blot analysis (288.8% ± 74.8 N=3). Additionally, we detected increased FGF receptor-1 protein expression (137.7% ± 0.4 N=3) as well as FGF signaling pathway activation. Next, we investigated the interaction of BMPER and the FGF signaling pathway in endothelial cell function. BMPER stimulation increased HUVEC angiogenic activity in matrigel, migration and spheroid assays and concomitant inhibition of FGF signaling by an anti-bFGF antibody effectively inhibited the pro-angiogenic BMPER effect. Silencing of BMPER decreased the expression of FGFR1 and, accordingly, stimulation of BMPER-silenced cells with bFGF showed decreased angiogenic endothelial cell activity (65%) compared to control. The angiogenic activity of bFGF was also reduced in C57BL/6_Bmper +/- mice as assessed in the matrigel plug assay. Ex vivo aortic ring assays of C57BL/6_Bmper +/- mice confirmed a specific effect for bFGF but not for VEGF. Conclusion: In summary, BMPER inhibits the expression of the anti-angiogenic TSP-1 and increased the expression as well as activation of the pro-angiogenic FGF signaling pathway, which overall lead to the promotion of angiogenesis.


1990 ◽  
Vol 259 (2) ◽  
pp. L123-L129
Author(s):  
K. B. Nolop ◽  
U. S. Ryan

Tumor necrosis factor (TNF), a potent polypeptide mediator released by activated monocytes and macrophages, has a number of proinflammatory effects on endothelial cells. TNF is cytotoxic to tumor cells in vivo and in vitro, but TNF-induced toxicity to endothelial cells is less well established. We now report that cycloheximide (CHX), an inhibitor of protein synthesis, renders endothelial cells highly susceptible to TNF-induced lysis. TNF alone did not change the overall rate of protein synthesis by endothelial cells, whereas the addition of CHX completely abolished protein synthesis. Endothelial cells incubated in TNF alone in high concentrations (up to 1,000 U/ml) showed minimal rounding up and release of 51Cr. Likewise, CHX alone (5 micrograms/ml) had no significant effect on endothelial cell morphology and release of 51Cr. However, incubation of endothelial cells in both CHX and TNF caused injury in a dose-dependent manner. Morphological evidence of cell retraction, rounding, and detachment began within 2 h, but specific 51Cr release did not begin to rise until after 4 h. These changes were not observed when endothelial cells were incubated with TNF/CHX at 4 degrees C. The combination of TNF/CHX was lethal to all endothelial cells tested (bovine pulmonary artery, human umbilical vein, and human aorta), with human aortic cells showing the most pronounced changes. We conclude that healthy endothelial cells are resistant to TNF-induced lysis, but inhibition of their ability to make protein renders them highly susceptible.


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.


Sign in / Sign up

Export Citation Format

Share Document