Endomembrane HRas Controls the PI3 Kinase/Akt/eNOS Signaling Cascade in VEGF Induced Endothelial Cell Migration

Abstract uPA plays an important role in angiogenesis: Originally, the urokinase system has been implicated to assist the angiogenic process by it’s proteolytic properties. It is now becoming increasingly evident that uPA additionally elicits many pro-angiogenic responses like differentiation, proliferation and cell migration in a non-proteolytic fashion via induction of intracellular signal transduction. In this study we demonstrate that in endothelial cells uPA protects against apoptosis by transcriptional upregulation of inhibitor of apoptosis proteins (IAPs), among them most prominently the X-linked inhibitor of apoptosis protein (XIAP). In contrast to canonical growth factors, like vascular endothelial growth factor (VEGF), uPA elicits anti-apoptosis independently of the PI3-kinase pathway. uPA-induced cell survival is dependent on the type of extracellular matrix used indicating the involvement of integrin adhesion receptors. Thereby, uPA induces phosphorylation of the CDC42 downstream effector p21-activated kinase 1 (PAK1), which leads to IkappaB kinase alpha (IKKa) phosphorylation, a prerequisite for NFkappaB activation. Blocking NFkappaB by using the specific NFkappaB inhibitor BAY 11–7082 or by adenoviral-mediated overexpression of its inhibitor, IkB, inhibits uPA-induced XIAP expression as well as uPA-induced cell survival. Downregulating XIAP expression by small interfering RNA techniques significantly reduces cell survival efficiencies of uPA in endothelial cells. From these data we conclude that uPA activation, which is a main player in endothelial cell migration and invasion, provides an additional, PI3-kinase independent cell survival mechanism.

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Distinct Vegfa isoforms control endothelial cell proliferation through PI3 kinase signalling mediated regulation of cdkn1a/p21

10.1101/2020.04.01.018796 ◽

2020 ◽

Author(s):

Martin Lange ◽

Elvin Leonard ◽

Nils Ohnesorge ◽

Dennis Hoffmann ◽

Susana F. Rocha ◽

...

Keyword(s):

Extracellular Matrix ◽

Cell Proliferation ◽

Cell Migration ◽

Endothelial Cell ◽

Pi3 Kinase ◽

Endothelial Cell Migration ◽

Endothelial Cell Proliferation ◽

Downstream Signaling ◽

Matrix Bound ◽

Cell Migration And Proliferation

SUMMARYThe formation of appropriately patterned blood vessel networks requires endothelial cell migration and proliferation. Signaling through the Vascular Endothelial Growth Factor A (VEGFA) pathway is instrumental in coordinating these processes. mRNA splicing generates short (diffusible) and long (extracellular matrix bound) Vegfa isoforms. The differences between these isoforms in controlling cellular functions are not understood. In zebrafish, vegfaa generates short and long isoforms, while vegfab only generates long isoforms. We found that mutations in vegfaa affected endothelial cell migration and proliferation. Surprisingly, mutations in vegfab specifically reduced endothelial cell proliferation. Analysis of downstream signaling revealed no change in MAPK (ERK) activation, while inhibiting PI3 kinase signaling phenocopied vegfab mutants. The cell cycle inhibitor cdkn1a/p21 was upregulated in vegfab deficient embryos. Accordingly, reducing cdkn1a/p21 restored endothelial cell proliferation. Together, these results suggest that extracellular matrix bound Vegfa acts through PI3K signaling to specifically control endothelial cell proliferation during angiogenesis independently of MAPK (ERK) regulation.

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Signaling and regulation of endothelial cell survival by angiopoietin-2

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01318.2005 ◽

2006 ◽

Vol 291 (4) ◽

pp. H1635-H1645 ◽

Cited By ~ 49

Author(s):

Rania Harfouche ◽

Sabah N. A. Hussain

Keyword(s):

Cell Migration ◽

Endothelial Cell ◽

Cell Survival ◽

Umbilical Vein ◽

Biological Effects ◽

Pi3 Kinase ◽

Endothelial Cell Migration ◽

Endothelial Cell Survival ◽

Induced Apoptosis

Angiopoietins are ligands for endothelial cell-specific Tie-2 receptors. Whereas angiopoietin-1 (Ang-1) activates these receptors and promotes cell survival, migration, and sprouting, little information is available regarding how Ang-2 influences these cells. In this study, we evaluated signaling pathways and biological effects of physiological concentrations of Ang-2 in cultured human umbilical vein endothelial cells. Ang-2 at 150 and 300 ng/ml elicited a transient (reaching peak values within 15 min of exposure) increase in the phosphorylation of Tie-2 receptors, protein kinase B (Akt), ERK1/2, and p38 members of the mitogen-activated protein kinases. However, unlike Ang-1, Ang-2 significantly inhibited JNK/SAPK phosphorylation. When vascular endothelial growth factor (VEGF) was present along with Ang-2, ERK1/2 phosphorylation was inhibited, whereas augmentation of Ang-1-induced ERK1/2 phosphorylation was triggered by VEGF. Ang-2 treatment had no effect on cell migration and in vitro wound healing but significantly attenuated serum deprivation-induced apoptosis and promoted survival. These effects were completely reversed by phosphatidylinositol 3 (PI3)-kinase and ERK1/2 inhibitors but were augmented by an inhibitor of the p38 pathway. These results suggest that Ang-2 promotes endothelial cell survival through the ERK1/2 and PI3-kinase pathways and that this angiopoietin is not a strong promoter of endothelial cell migration. We also conclude that the nature of interactions in terms of ERK1/2 activation between Ang-2 and VEGF is different from that of Ang-1 and VEGF.

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Polyphenols-rich Fruit Extracts Modulate Endothelial Cell Migration via PI3 Kinase/Akt pathway in vitro in Human Umbilical Vein Endothelial Cells

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2010.10.507 ◽

2010 ◽

Vol 49 ◽

pp. S178-S179

Author(s):

Claire Wei-Ju Chang ◽

Indika Edirisinghe ◽

Joseph E Jablonski ◽

Ravi K Tadapaneni ◽

Artemio Z Tulio ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Endothelial Cell ◽

Umbilical Vein ◽

Pi3 Kinase ◽

Endothelial Cell Migration ◽

Akt Pathway ◽

Human Umbilical Vein ◽

Umbilical Vein Endothelial Cells

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Activation of the Phosphatidylinositol 3-Kinase/Protein Kinase Akt Pathway Mediates Nitric Oxide-Induced Endothelial Cell Migration and Angiogenesis

Molecular and Cellular Biology ◽

10.1128/mcb.23.16.5726-5737.2003 ◽

2003 ◽

Vol 23 (16) ◽

pp. 5726-5737 ◽

Cited By ~ 177

Author(s):

Koh Kawasaki ◽

Robert S. Smith ◽

Chung-Ming Hsieh ◽

Jianxin Sun ◽

Julie Chao ◽

...

Keyword(s):

Nitric Oxide ◽

Cell Migration ◽

Endothelial Cell ◽

Protein Kinase ◽

Hind Limb ◽

Soluble Guanylyl Cyclase ◽

Pi3 Kinase ◽

Endothelial Cell Migration ◽

Phosphatidylinositol 3 Kinase ◽

Protein Kinase Akt

ABSTRACT To test the hypothesis that the phosphatidylinositol 3-kinase (PI3 kinase)/protein kinase Akt signaling pathway is involved in nitric oxide (NO)-induced endothelial cell migration and angiogenesis, we treated human and bovine endothelial cells with NO donors, S-nitroso-l-glutathione (GSNO) and S-nitroso-N-penicillamine (SNAP). Both GSNO and SNAP increased Akt phosphorylation and activity, which were blocked by cotreatment with the PI3 kinase inhibitor wortmannin. The mechanism was due to the activation of soluble guanylyl cyclase because 8-bromo-cyclic GMP activated PI3 kinase and the soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-α]quinoxalin-1-one (ODQ) blocked NO-induced PI3 kinase activity. Indeed, transfection with adenovirus containing endothelial cell NO synthase (eNOS) or protein kinase G (PKG) increased endothelial cell migration, which was inhibited by cotransfection with a dominant-negative mutant of PI3 kinase (dnPI3 kinase). In a rat model of hind limb ischemia, adenovirus-mediated delivery of human eNOS cDNA in adductor muscles resulted in time-dependent expression of recombinant eNOS, which was accompanied by significant increases in regional blood perfusion and capillary density. Coinjection of adenovirus carrying dnPI3 kinase abolished neovascularization in ischemic hind limb induced by eNOS gene transfer. These findings indicate that NO promotes endothelial cell migration and neovascularization via cGMP-dependent activation of PI3 kinase and suggest that this pathway is important in mediating NO-induced angiogenesis.

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Domain 5 of cleaved high molecular weight kininogen inhibits endothelial cell migration through Akt

Thrombosis and Haemostasis ◽

10.1160/th04-12-0834 ◽

2005 ◽

Vol 94 (09) ◽

pp. 606-614 ◽

Cited By ~ 12

Author(s):

Vaibhav Katkade ◽

Abigail A. Soyombo ◽

Irma Isordia-Salas ◽

Harlan N. Bradford ◽

John P. Gaughan ◽

...

Keyword(s):

Molecular Weight ◽

Cell Migration ◽

Endothelial Cell ◽

Signaling Pathways ◽

High Molecular Weight ◽

Focal Adhesions ◽

Akt Signaling ◽

Pi3 Kinase ◽

Endothelial Cell Migration ◽

High Molecular Weight Kininogen

SummaryDomain 5 (D5) of cleaved high molecular weight kininogen (HKa) inhibits angiogenesis in vivo and endothelial cell migration in vitro, but the cell signaling pathways involved in HKa and D5 inhibition of endothelial cell migration are incompletely delineated. This study examines the mechanism of HKa and D5 inhibition of two potent stimulators of endothelial cell migration, sphingosine 1-phosphate (S1P) and vascular endothelial growth factor (VEGF), that act through the PI3-kinase-Akt signaling pathway. HKa and D5 inhibit bovine pulmonary artery endothelial cell (BPAE) or human umbilical vein endothelial cell chemotaxis in the modified-Boyden chamber in response to VEGF or S1P. The inhibition of migration by HKa is reversed by antibodies to urokinase-type plasminogen activator receptor. Both HKa and D5 decrease the speed of BPAE cell migration and alter the morphology in live, time-lapse microscopy after stimulation with S1P or VEGF. HKa and D5 reduce the localization of paxillin to the focal adhesions after S1P and VEGF stimulation. To better understand the intracellular signaling pathways, we examined the effect of HKa on the phosphorylation of Akt and its downstream effector, GSK-3α.HKa and D5 inhibit phosphorylation of Akt and GSK-3α after stimulation withVEGF and S1P. Inhibitors of Akt and PI3-kinase, the upstream activator of Akt, block endothelial cell migration and disrupt paxillin localization to the focal adhesions after stimulation with VEGF and S1P. Therefore we suggest that HKa through its D5 domain alters PI3-kinase- Akt signaling to inhibit endothelial cell migration through alterations in the focal adhesions.

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