Matrix stiffening promotes a tumor vasculature phenotype

Tumor microvasculature tends to be malformed, more permeable, and more tortuous than vessels in healthy tissue, effects that have been largely attributed to up-regulated VEGF expression. However, tumor tissue tends to stiffen during solid tumor progression, and tissue stiffness is known to alter cell behaviors including proliferation, migration, and cell–cell adhesion, which are all requisite for angiogenesis. Using in vitro, in vivo, and ex ovo models, we investigated the effects of matrix stiffness on vessel growth and integrity during angiogenesis. Our data indicate that angiogenic outgrowth, invasion, and neovessel branching increase with matrix cross-linking. These effects are caused by increased matrix stiffness independent of matrix density, because increased matrix density results in decreased angiogenesis. Notably, matrix stiffness up-regulates matrix metalloproteinase (MMP) activity, and inhibiting MMPs significantly reduces angiogenic outgrowth in stiffer cross-linked gels. To investigate the functional significance of altered endothelial cell behavior in response to matrix stiffness, we measured endothelial cell barrier function on substrates mimicking the stiffness of healthy and tumor tissue. Our data indicate that barrier function is impaired and the localization of vascular endothelial cadherin is altered as function of matrix stiffness. These results demonstrate that matrix stiffness, separately from matrix density, can alter vascular growth and integrity, mimicking the changes that exist in tumor vasculature. These data suggest that therapeutically targeting tumor stiffness or the endothelial cell response to tumor stiffening may help restore vessel structure, minimize metastasis, and aid in drug delivery.

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Shock-induced stress induces loss of microvascular endothelial Tie2 in the kidney which is not associated with reduced glomerular barrier function

AJP Renal Physiology ◽

10.1152/ajprenal.00137.2009 ◽

2009 ◽

Vol 297 (2) ◽

pp. F272-F281 ◽

Cited By ~ 36

Author(s):

Matijs van Meurs ◽

Neng F. Kurniati ◽

Francis M. Wulfert ◽

Sigridur A. Asgeirsdottir ◽

Inge A. de Graaf ◽

...

Keyword(s):

Endothelial Cell ◽

Barrier Function ◽

Human Kidney ◽

Mrna Levels ◽

Barrier Dysfunction ◽

Molecular Control ◽

Filtration Barrier ◽

Glomerular Barrier

Both hemorrhagic shock and endotoxemia induce a pronounced vascular activation in the kidney which coincides with albuminuria and glomerular barrier dysfunction. We hypothesized that changes in Tie2, a vascular restricted receptor tyrosine kinase shown to control microvascular integrity and endothelial inflammation, underlie this loss of glomerular barrier function. In healthy murine and human kidney, Tie2 is heterogeneously expressed in all microvascular beds, although to different extents. In mice subjected to hemorrhagic and septic shock, Tie2 mRNA and protein were rapidly, and temporarily, lost from the renal microvasculature, and normalized within 24 h after initiation of the shock insult. The loss of Tie2 protein could not be attributed to shedding as both in mice and healthy volunteers subjected to endotoxemia, sTie2 levels in the systemic circulation did not change. In an attempt to identify the molecular control of Tie2, we activated glomerular endothelial cell cultures and human kidney slices in vitro with LPS or TNF-α, but did not observe a change in Tie2 mRNA levels. In parallel to the loss of Tie2 in vivo, an overt influx of neutrophils in the glomerular compartment, which coincided with proteinuria, was seen. As neutrophil-endothelial cell interactions may play a role in endothelial adaptation to shock, and these effects cannot be mimicked in vitro, we depleted neutrophils before shock induction. While this neutrophil depletion abolished proteinuria, Tie2 was not rescued, implying that Tie2 may not be a major factor controlling maintenance of the glomerular filtration barrier in this model.

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Abstract 15187: Shear Stress-regulated Mir-27b Controls Pericyte Recruitment in vitro and in vivo and Contributes to Vessel Maturation

Circulation ◽

10.1161/circ.132.suppl_3.15187 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Shemsi Demolli ◽

Anuradha Doddaballapur ◽

Konstantin Stark ◽

Reinier A Boon ◽

Ankathrin Eckart ◽

...

Keyword(s):

Shear Stress ◽

Endothelial Cell ◽

Barrier Function ◽

Molecular Mechanisms ◽

Laminar Shear Stress ◽

Pericyte Coverage ◽

Vessel Maturation ◽

Laminar Shear

Vessel maturation involves recruitment of mural cells. Laminar shear stress is a major trigger for vessel maturation. However, the molecular mechanisms by which shear stress affects recruitment of pericytes are unclear. MicroRNAs are small non-coding RNAs, which post-transcriptionally control gene expression. Since shear stress regulates various miRs, we hypothesize that flow-induced miRs inhibit repulsive cues and facilitate mural cell coverage. Laminar shear stress for 72h induces the up-regulation of miR-27b (2.8±0.24-fold vs static, p<0.05) in cultured endothelial cells (ECs) and in mouse femoral artery segments that were exposed to physiological shear stress ex vivo (1.5±0.14-fold vs no flow, p<0.05). Predicted targets for miR-27b include members of the semaphorin (SEMA) family (known to regulate repulsive signaling) and angiopoietin-2 (Ang2), which causes vessel destabilization. MiR-27b overexpression reduces SEMA6A (63.5±13.5%), SEMA6D (58±26%), and Ang2 (51.5±11%) expression. To determine whether miR-27b controls pericyte recruitment, we tested the effect of endothelial miR-27b on adhesion of pericytes. Overexpression of miR-27b increased the adhesion of pericytes (p<0.05) and inhibition of miR-27b reduced pericyte adhesion in vitro (p<0.05). In an in vitro matrigel assay, overexpression of miR-27b increased pericyte coverage of endothelial cell tubes (155±45%, p<0.05), whereas inhibition of miR-27b reduced pericyte coverage (81±15%). In addition, overexpression of miR-27b in vitro increases barrier function (p<0.05) in endothelial cell-pericyte co-culture assays whereas inhibition of miR-27b decreases barrier function (p<0.05). Silencing of SEMA6A and SEMA6D rescued the reduced pericyte adhesion that is caused by miR-27 inhibition (p<0.05). Furthermore, inhibition of SEMA6D increases barrier function. In vivo inhibition of miR-27a/b significantly increased edema (p<0.05) in the uterus which was associated with a significantly reduced pericyte coverage of the vessels (p<0.05). Taken together, our data demonstrate that shear stress regulate miR-27b, which targets Ang2 and semaphorins, thereby controlling pericyte adhesion and coverage in vitro and in vivo.

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Endogenous hydrogen sulfide sulfhydrates IKKβ at cysteine 179 to control pulmonary artery endothelial cell inflammation

Clinical Science ◽

10.1042/cs20190514 ◽

2019 ◽

Vol 133 (20) ◽

pp. 2045-2059 ◽

Cited By ~ 4

Author(s):

Da Zhang ◽

Xiuli Wang ◽

Siyao Chen ◽

Selena Chen ◽

Wen Yu ◽

...

Keyword(s):

Hydrogen Sulfide ◽

Endothelial Cell ◽

Pulmonary Artery ◽

Cell Model ◽

Site Directed Mutagenesis ◽

Critical Event ◽

Hypertensive Rats ◽

Pulmonary Artery Endothelial Cell

Abstract Background: Pulmonary artery endothelial cell (PAEC) inflammation is a critical event in the development of pulmonary arterial hypertension (PAH). However, the pathogenesis of PAEC inflammation remains unclear. Methods: Purified recombinant human inhibitor of κB kinase subunit β (IKKβ) protein, human PAECs and monocrotaline-induced pulmonary hypertensive rats were employed in the study. Site-directed mutagenesis, gene knockdown or overexpression were conducted to manipulate the expression or activity of a target protein. Results: We showed that hydrogen sulfide (H2S) inhibited IKKβ activation in the cell model of human PAEC inflammation induced by monocrotaline pyrrole-stimulation or knockdown of cystathionine γ-lyase (CSE), an H2S generating enzyme. Mechanistically, H2S was proved to inhibit IKKβ activity directly via sulfhydrating IKKβ at cysteinyl residue 179 (C179) in purified recombinant IKKβ protein in vitro, whereas thiol reductant dithiothreitol (DTT) reversed H2S-induced IKKβ inactivation. Furthermore, to demonstrate the significance of IKKβ sulfhydration by H2S in the development of PAEC inflammation, we mutated C179 to serine (C179S) in IKKβ. In purified IKKβ protein, C179S mutation of IKKβ abolished H2S-induced IKKβ sulfhydration and the subsequent IKKβ inactivation. In human PAECs, C179S mutation of IKKβ blocked H2S-inhibited IKKβ activation and PAEC inflammatory response. In pulmonary hypertensive rats, C179S mutation of IKKβ abolished the inhibitory effect of H2S on IKKβ activation and pulmonary vascular inflammation and remodeling. Conclusion: Collectively, our in vivo and in vitro findings demonstrated, for the first time, that endogenous H2S directly inactivated IKKβ via sulfhydrating IKKβ at Cys179 to inhibit nuclear factor-κB (NF-κB) pathway activation and thereby control PAEC inflammation in PAH.

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Organische Nitrate und Thrombozytenfunktion

Hämostaseologie ◽

10.1055/s-0038-1659867 ◽

1988 ◽

Vol 08 (02) ◽

pp. 90-99 ◽

Cited By ~ 7

Author(s):

H. Schröder ◽

K. Schrör

Keyword(s):

Endothelial Cell ◽

Angina Pectoris ◽

Ex Vivo

ZusammenfassungOrganische Nitrate unterschiedlicher chemischer Struktur sowie Nitroprussidnatrium und Molsidomin (bzw. ihre biologisch aktiven Metaboliten) können die (primäre) Aggregation und Sekretion von Humanthrombozyten in vitro und ex vivo hemmen. Eine solche Wirkung wird für Molsidomin (SIN-1) und Nitroprussidnatrium in vitro in Konzentrationen beobachtet, die in der gleichen Größenordnung liegen wie die vasodilatierenden Effekte der Substanzen. Dagegen sind für eine direkte Antiplättchenwirkung organischer Nitrate (Glyzeryltrinitrat, Isosorbiddinitr at, Isosorbidmononitrate, Teopranitol) in vitro Konzentrationen erforderlich, die ca. 100- bis 1000fach höher sind als die Plasmaspiegel der Substanzen nach therapeutischer Dosierung bzw. die Konzentrationen, die isolierte Gefäßstreifen relaxieren. Als gemeinsamer Wirkungsmechanismus der direkten thrombozy-tenfunktionshemmenden und gefäßerweiternden Wirkung all dieser Substanzen kann heute eine Stickoxid-(NO)-vermittelte Stimulation der cGMP-Bildung angenommen werden, das aus organischen Nitraten als »Pro-drug« entsteht. Die Freisetzung von NO, eines »endothelial cell-derived relaxing factors« (EDRF) aus Nitroprussidnatrium und SIN-1 erfolgt spontan. Dagegen erfordert die Freisetzung von NO aus organischen Nitraten einen enzymatischen Stoffwechselweg, der in isolierten Thrombozyten nicht vorhanden ist. Eine Antiplättchenwirkung organischer Nitrate in vivo bzw. ex vivo wird daher über die Stimulation eines endothelialen, thrombozyteninhibitorischen Faktors erklärt. Hierbei sind Prostazyklin sowie ein bisher unbekannter Endothel-zellfaktor neben einer synergistischen Wirkung organischer Nitrate mit endogenem Prostazyklin in Diskussion. Eine thrombozytenfunktionshemmen-de Wirkung organischer Nitrate könnte in Kombination mit ihren hämody-namischen Effekten auch für die an-tianginöse Wirkung in der Klinik bedeutsam sein, insbesondere zur Verhinderung vasospastischer Zustände bei der instabilen Angina pectoris.

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Faculty Opinions recommendation of The hydrodynamically relevant endothelial cell glycocalyx observed in vivo is absent in vitro.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1099471.555740 ◽

2008 ◽

Author(s):

Klaus Ley

Keyword(s):

Endothelial Cell

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The role of anti-endothelial cell antibodies in Kawasaki disease -in vitro and in vivo studies

Clinical & Experimental Immunology ◽

10.1046/j.1365-2249.2002.02000.x ◽

2002 ◽

Vol 130 (2) ◽

pp. 233-240 ◽

Cited By ~ 50

Author(s):

E. GRUNEBAUM ◽

M. BLANK ◽

S. COHEN ◽

A. AFEK ◽

J. KOPOLOVIC ◽

...

Keyword(s):

Endothelial Cell ◽

Kawasaki Disease ◽

In Vivo Studies

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The oncogenic role of the cerebral endothelial cell adhesion molecule (CERCAM) in bladder cancer cells in vitro and in vivo

Cancer Medicine ◽

10.1002/cam4.3955 ◽

2021 ◽

Author(s):

Yali Zuo ◽

Xiaoliang Xu ◽

Minfeng Chen ◽

Lin Qi

Keyword(s):

Bladder Cancer ◽

Cell Adhesion ◽

Endothelial Cell ◽

Adhesion Molecule ◽

Cell Adhesion Molecule ◽

Bladder Cancer Cells ◽

Endothelial Cell Adhesion

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Differentiated glioblastoma cells accelerate tumor progression by shaping the tumor microenvironment via CCN1-mediated macrophage infiltration

Acta Neuropathologica Communications ◽

10.1186/s40478-021-01124-7 ◽

2021 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Atsuhito Uneda ◽

Kazuhiko Kurozumi ◽

Atsushi Fujimura ◽

Kentaro Fujii ◽

Joji Ishida ◽

...

Keyword(s):

Tumor Microenvironment ◽

Tumor Progression ◽

Tumor Cells ◽

In Silico ◽

Tumor Tissue ◽

The Cancer Genome Atlas ◽

Macrophage Infiltration ◽

Macrophage Migration

AbstractGlioblastoma (GBM) is the most lethal primary brain tumor characterized by significant cellular heterogeneity, namely tumor cells, including GBM stem-like cells (GSCs) and differentiated GBM cells (DGCs), and non-tumor cells such as endothelial cells, vascular pericytes, macrophages, and other types of immune cells. GSCs are essential to drive tumor progression, whereas the biological roles of DGCs are largely unknown. In this study, we focused on the roles of DGCs in the tumor microenvironment. To this end, we extracted DGC-specific signature genes from transcriptomic profiles of matched pairs of in vitro GSC and DGC models. By evaluating the DGC signature using single cell data, we confirmed the presence of cell subpopulations emulated by in vitro culture models within a primary tumor. The DGC signature was correlated with the mesenchymal subtype and a poor prognosis in large GBM cohorts such as The Cancer Genome Atlas and Ivy Glioblastoma Atlas Project. In silico signaling pathway analysis suggested a role of DGCs in macrophage infiltration. Consistent with in silico findings, in vitro DGC models promoted macrophage migration. In vivo, coimplantation of DGCs and GSCs reduced the survival of tumor xenograft-bearing mice and increased macrophage infiltration into tumor tissue compared with transplantation of GSCs alone. DGCs exhibited a significant increase in YAP/TAZ/TEAD activity compared with GSCs. CCN1, a transcriptional target of YAP/TAZ, was selected from the DGC signature as a candidate secreted protein involved in macrophage recruitment. In fact, CCN1 was secreted abundantly from DGCs, but not GSCs. DGCs promoted macrophage migration in vitro and macrophage infiltration into tumor tissue in vivo through secretion of CCN1. Collectively, these results demonstrate that DGCs contribute to GSC-dependent tumor progression by shaping a mesenchymal microenvironment via CCN1-mediated macrophage infiltration. This study provides new insight into the complex GBM microenvironment consisting of heterogeneous cells.

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