DIRECT CELL CONTACT BETWEEN BRAIN ENDOTHELIAL CELLS AND GLIOMA STEM CELLS PROMOTES ENDOTHELIAL CELL MIGRATION

Abstract Prostaglandin E2 (PGE2) plays a crucial role in angiogenesis as well as in ischemic and inflammatory disorders of the brain associated with breakdown of the blood-brain barrier. However, the effects of PGE2 on brain endothelial cell migration, a key process in the angiogenic response and blood-brain barrier stability, are not well defined. Exposure of human brain endothelial cells (HBECs) to PGE2 elicited a chemotactic response in a time- and dose-dependent manner. The maximum migratory response was detected following 8 hours exposure of HBECs to PGE2 (100 nM). Migration of HBECs in response to PGE2 was accompanied by profound changes in the reorganization of actin filaments. Fluorescence microscopy examination of NBD-phallacidin-labeled endothelial cells showed increased formation of stress fibers, lamellipodia and podosomes after treatment with PGE2 (100 nM) compared to control. Based on these results, we hypothesized that Rho-kinase (ROCK), an enzyme involved in regulation of actin dynamics and cell migration, mediated the effects of PGE2 on HBEC migration. Western blot analyses revealed that ROCK II (type alpha), but not ROCK I (type beta), was expressed in HBECs. To examine ROCK II activation, we performed immunocomplex kinase assays using myosin light chain (MLC) as a substrate. PGE2 (100 nM) induced a 2-fold increase of 32P-incorporation into MLC indicating activation of ROCK II. Pretreatment of HBECs with the selective ROCK inhibitor, Y27632 (150 nM), blunted HBEC migration in response to PGE2 but had no effect on migration induced by fetal bovine serum (10%). Knockdown of ROCK II by siRNA also abrogated the migratory response of HBECs to PGE2. In contrast, similar treatment had no effect of HBEC migration stimulated by hepatocyte growth factor. Taken together, these results are consistent with the hypothesis that stimulation of HBECs with PGE2 leads to activation of ROCK II, reorganization of the actin cytoskeleton and ultimately migration. A better characterization of the molecular events that regulate migration of brain endothelial cells is critical for the development of novel strategies to treat cerebrovascular diseases associated with deregulated angiogenesis.

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Glioma stem cells enhance endothelial cell migration and proliferation via the Hedgehog pathway

Oncology Letters ◽

10.3892/ol.2013.1569 ◽

2013 ◽

Vol 6 (5) ◽

pp. 1524-1530 ◽

Cited By ~ 13

Author(s):

GUANG-NING YAN ◽

YANG-FAN LV ◽

LANG YANG ◽

XIAO-HONG YAO ◽

YOU-HONG CUI ◽

...

Keyword(s):

Stem Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Hedgehog Pathway ◽

Endothelial Cell Migration ◽

Glioma Stem Cells ◽

Cell Migration And Proliferation

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Reactive oxygen species mediate Rac-induced loss of cell-cell adhesion in primary human endothelial cells

Journal of Cell Science ◽

10.1242/jcs.115.9.1837 ◽

2002 ◽

Vol 115 (9) ◽

pp. 1837-1846 ◽

Cited By ~ 2

Author(s):

Sandra van Wetering ◽

Jaap D. van Buul ◽

Safira Quik ◽

Frederik P. J. Mul ◽

Eloise C. Anthony ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Endothelial Cells ◽

Cell Migration ◽

Cell Adhesion ◽

Endothelial Cell ◽

Reactive Oxygen ◽

Small Gtpases ◽

Endothelial Cell Migration ◽

Oxygen Species ◽

Cell Cell

The integrity of the endothelium is dependent on cell-cell adhesion, which is mediated by vascular-endothelial (VE)-cadherin. Proper VE-cadherin-mediated homotypic adhesion is, in turn, dependent on the connection between VE-cadherin and the cortical actin cytoskeleton. Rho-like small GTPases are key molecular switches that control cytoskeletal dynamics and cadherin function in epithelial as well as endothelial cells. We show here that a cell-penetrating, constitutively active form of Rac (Tat-RacV12) induces a rapid loss of VE-cadherin-mediated cell-cell adhesion in endothelial cells from primary human umbilical veins (pHUVEC). This effect is accompanied by the formation of actin stress fibers and is dependent on Rho activity. However,transduction of pHUVEC with Tat-RhoV14, which induces pronounced stress fiber and focal adhesion formation, did not result in a redistribution of VE-cadherin or an overall loss of cell-cell adhesion. In line with this observation, endothelial permeability was more efficiently increased by Tat-RacV12 than by Tat-RhoV14. The loss of cell-cell adhesion, which is induced by Tat-RacV12, occurred in parallel to and was dependent upon the intracellular production of reactive oxygen species (ROS). Moreover, Tat-RacV12 induced an increase in tyrosine phosphorylation of a component the VE-cadherin-catenin complex, which was identified as α-catenin. The functional relevance of this signaling pathway was further underscored by the observation that endothelial cell migration, which requires a transient reduction of cell-cell adhesion, was blocked when signaling through ROS was inhibited. In conclusion, Rac-mediated production of ROS represents a previously unrecognized means of regulating VE-cadherin function and may play an important role in the (patho)physiology associated with inflammation and endothelial damage as well as with endothelial cell migration and angiogenesis.

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CRIF1 deficiency suppresses endothelial cell migration via upregulation of RhoGDI2

PLoS ONE ◽

10.1371/journal.pone.0256646 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256646

Author(s):

Harsha Nagar ◽

Seonhee Kim ◽

Ikjun Lee ◽

Su-Jeong Choi ◽

Shuyu Piao ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Signaling Pathway ◽

Umbilical Vein ◽

Vascular Endothelial Cell ◽

Cellular Migration ◽

Endothelial Cell Migration ◽

Migration And Invasion ◽

Mitochondrial Functions

Rho GDP-dissociation inhibitor (RhoGDI), a downregulator of Rho family GTPases, prevents nucleotide exchange and membrane association. It is responsible for the activation of Rho GTPases, which regulate a variety of cellular processes, such as migration. Although RhoGDI2 has been identified as a tumor suppressor gene involved in cellular migration and invasion, little is known about its role in vascular endothelial cell (EC) migration. CR6-interacting factor 1 (CRIF1) is a CR6/GADD45-interacting protein with important mitochondrial functions and regulation of cell growth. We examined the expression of RhoGDI2 in CRIF1-deficient human umbilical vein endothelial cells (HUVECs) and its role in cell migration. Expression of RhoGDI2 was found to be considerably higher in CRIF1-deficient HUVECs along with suppression of cell migration. Moreover, the phosphorylation levels of Akt and CREB were decreased in CRIF1-silenced cells. The Akt-CREB signaling pathway was implicated in the changes in endothelial cell migration caused by CRIF1 downregulation. In addition to RhoGDI2, we identified another factor that promotes migration and invasion of ECs. Adrenomedullin2 (ADM2) is an autocrine/paracrine factor that regulates vascular tone and other vascular functions. Endogenous ADM2 levels were elevated in CRIF1-silenced HUVECs with no effect on cell migration. However, siRNA-mediated depletion of RhoGDI2 or exogenous ADM2 administration significantly restored cell migration via the Akt-CREB signaling pathway. In conclusion, RhoGDI2 and ADM2 play important roles in the migration of CRIF1-deficient endothelial cells.

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Skeletal muscle-endothelial cell cross talk through angiotensin II

AJP Cell Physiology ◽

10.1152/ajpcell.00306.2010 ◽

2010 ◽

Vol 299 (6) ◽

pp. C1402-C1408 ◽

Cited By ~ 17

Author(s):

Leeann M. Bellamy ◽

Adam P. W. Johnston ◽

Michael De Lisio ◽

Gianni Parise

Keyword(s):

Skeletal Muscle ◽

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Angiotensin Ii ◽

Branch Point ◽

Endothelial Cell Migration ◽

Tube Length ◽

Ang Ii

The role of angiotensin II (ANG II) in postnatal vasculogenesis and angiogenesis during skeletal muscle (SKM) regeneration is unknown. We examined the capacity of ANG II to stimulate capillary formation and growth during cardiotoxin-induced muscle regeneration in ACE inhibitor-treated ANG II type 1a receptor knockout (AT1a−/−) and C57Bl/6 control mice. Analysis of tibialis anterior (TA) cross-sections revealed 17% and 23% reductions in capillarization in AT1a−/− and captopril treated mice, respectively, when compared with controls, 21 days postinjury. Conversely, no differences in capillarization were detected at early time points (7 and 10 days). These results identify ANG II as a regulator of angiogenesis but not vasculogenesis in vivo. In vitro angiogenesis assays of human umbilical vein endothelial cells (HUVECs) further confirmed ANG II as proangiogeneic as 71% and 124% increases in tube length and branch point number were observed following ANG II treatment. Importantly, treatment of HUVECs with conditioned media from differentiated muscle cells resulted in an 84% and 203% increase in tube length and branch point number compared with controls, which was abolished following pretreatment of the cells with an angiotensin-converting enzyme inhibitor. The pro-angiogenic effect of ANG II can be attributed to an enhanced endothelial cell migration because both transwell and under agarose migration assays revealed a 37% and 101% increase in cell motility, respectively. Collectively, these data highlight ANG II as a proangiogenic regulator during SKM regeneration in vivo and more importantly demonstrates that ANG II released from SKM can signal endothelial cells and regulate angiogenesis through the induction of endothelial cell migration.

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Vascular endothelial growth factor (VEGF) in cartilage neovascularization and chondrocyte differentiation: auto-paracrine role during endochondral bone formation

Journal of Cell Science ◽

10.1242/jcs.113.1.59 ◽

2000 ◽

Vol 113 (1) ◽

pp. 59-69 ◽

Cited By ~ 8

Author(s):

M.F. Carlevaro ◽

S. Cermelli ◽

R. Cancedda ◽

F. Descalzi Cancedda

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Hypertrophic Chondrocytes ◽

Endothelial Cell Migration ◽

Vegf Receptor ◽

Hypertrophic Cartilage ◽

Endothelial Growth Factor

Vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) induces endothelial cell migration and proliferation in culture and is strongly angiogenic in vivo. VEGF synthesis has been shown to occur in both normal and transformed cells. The receptors for the factor have been shown to be localized mainly in endothelial cells, however, the presence of VEGF synthesis and the VEGF receptor in cells other than endothelial cells has been demonstrated. Neoangiogenesis in cartilage growth plate plays a fundamental role in endochondral ossification. We have shown that, in an avian in vitro system for chondrocyte differentiation, VEGF was produced and localized in cell clusters totally resembling in vivo cartilage. The factor was synthesized by hypertrophic chondrocytes and was released into their conditioned medium, which is highly chemotactic for endothelial cells. Antibodies against VEGF inhibited endothelial cell migration induced by chondrocyte conditioned media. Similarly, endothelial cell migration was inhibited also by antibodies directed against the VEGF receptor 2/Flk1 (VEGFR2). In avian and mammalian embryo long bones, immediately before vascular invasion, VEGF was distinctly localized in growth plate hypertrophic chondrocytes. In contrast, VEGF was not observed in quiescent and proliferating chondrocytes earlier in development. VEGF receptor 2 colocalized with the factor both in hypertrophic cartilage in vivo and hypertrophic cartilage engineered in vitro, suggesting an autocrine loop in chondrocytes at the time of their maturation to hypertrophic cells and of cartilage erosion. Regardless of cell exposure to exogenous VEGF, VEGFR-2 phosphorylation was recognized in cultured hypertrophic chondrocytes, supporting the idea of an autocrine functional activation of signal transduction in this non-endothelial cell type as a consequence of the endogenous VEGF production. In summary we propose that VEGF is actively responsible for hypertrophic cartilage neovascularization through a paracrine release by chondrocytes, with invading endothelial cells as a target. Furthermore, VEGF receptor localization and signal transduction in chondrocytes strongly support the hypothesis of a VEGF autocrine activity also in morphogenesis and differentiation of a mesoderm derived cell.

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Abstract 5288: Glioma stem cells stimulate the motility of brain endothelial cells: Identification of cell-adhesion molecules mediating motility and direct interaction

10.1158/1538-7445.am2012-5288 ◽

2012 ◽

Author(s):

Monica E. Burgett ◽

Russell S. Tipps ◽

Justin D. Lathia ◽

Shideng Bao ◽

Jeremy N. Rich ◽

...

Keyword(s):

Stem Cells ◽

Endothelial Cells ◽

Cell Adhesion ◽

Adhesion Molecules ◽

Cell Adhesion Molecules ◽

Direct Interaction ◽

Glioma Stem Cells ◽

Brain Endothelial Cells

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Tissue factor pathway inhibitor (TFPI) interferes with endothelial cell migration by inhibition of both the Erk pathway and focal adhesion proteins

Thrombosis and Haemostasis ◽

10.1160/th07-10-0623 ◽

2008 ◽

Vol 99 (03) ◽

pp. 576-585 ◽

Cited By ~ 19

Author(s):

Mathieu Provençal ◽

Marisol Michaud ◽

Édith Beaulieu ◽

David Ratel ◽

Georges-Étienne Rivard ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Tissue Factor ◽

Focal Adhesion ◽

Tissue Factor Pathway Inhibitor ◽

Endothelial Cell Migration ◽

Cell Functions ◽

Tissue Factor Pathway

SummaryTissue factor pathway inhibitor (TFPI) is a plasma Kunitz-type serine protease inhibitor that is mainly known for its inhibition of tissue factor-mediated coagulation. In addition to its anticoagulant properties, emerging data show that TFPI may also regulate endothelial cell functions via a non-haemostatic pathway. In this work we demonstrate that at concentrations within the physiological range,TFPI inhibits both endothelial cell migration and their differentiation into capillary-like structures in vitro. These effects were specific to endothelial cells since no inhibitory effect was observed on the migration of tumor (glio- blastoma) cells. Inhibition of endothelial cell migration was correlated with a concomitant loss in cell adhesion,suggesting an alteration of focal adhesion complex integrity. Accordingly,we observed thatTFPI inhibited the phosphorylation of focal adhesion kinase and paxillin,two key proteins involved in the scaffolding of these complexes, and that this effect was specific to endothelial cells. These results suggest that TFPI influences the angiogenic process via a non-haemostatic pathway, by downregulating the migratory mechanisms of endothelial cells.

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CYLD regulates angiogenesis by mediating vascular endothelial cell migration

Blood ◽

10.1182/blood-2009-10-248526 ◽

2010 ◽

Vol 115 (20) ◽

pp. 4130-4137 ◽

Cited By ~ 52

Author(s):

Jinmin Gao ◽

Lei Sun ◽

Lihong Huo ◽

Min Liu ◽

Dengwen Li ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Vascular Endothelial Cells ◽

Vascular Endothelial Cell ◽

Tube Formation ◽

Endothelial Cell Migration ◽

Vascular Endothelial

Cylindromatosis (CYLD) is a deubiquitinase that was initially identified as a tumor suppressor and has recently been implicated in diverse normal physiologic processes. In this study, we have investigated the involvement of CYLD in angiogenesis, the formation of new blood vessels from preexisting ones. We find that knockdown of CYLD expression significantly impairs angiogenesis in vitro in both matrigel-based tube formation assay and collagen-based 3-dimensional capillary sprouting assay. Disruption of CYLD also remarkably inhibits angiogenic response in vivo, as evidenced by diminished blood vessel growth into the angioreactors implanted in mice. Mechanistic studies show that CYLD regulates angiogenesis by mediating the spreading and migration of vascular endothelial cells. Silencing of CYLD dramatically decreases microtubule dynamics in endothelial cells and inhibits endothelial cell migration by blocking the polarization process. Furthermore, we identify Rac1 activation as an important factor contributing to the action of CYLD in regulating endothelial cell migration and angiogenesis. Our findings thus uncover a previously unrecognized role for CYLD in the angiogenic process and provide a novel mechanism for Rac1 activation during endothelial cell migration and angiogenesis.

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