Retinoblastoma cell-derived exosomes promote angiogenesis of human vesicle endothelial cells through microRNA‐92a-3p

AbstractExosomes derived from tumor cells play a key role in tumor development. In the present study, we identified the bioactivity of exosomes released from WERI-Rb1 retinoblastoma cells in tumor angiogenesis, as well as the underlying mechanism, through biochemical methods and animal experiments. Our in vitro data showed that exosomes could be engulfed by human vesicle endothelial cells (HUVECs), significantly promote cell viability and induce an inflammatory response in HUVECs by increasing the expression of a series of related genes, such as IL-1, IL-6, IL-8, MCP-1, VCAM1, and ICAM1. Significant increases in migration and tube formation were also observed in the HUVECs incubated with exosomes. Moreover, experiments with a nude mouse xenotransplantation model showed that exosomes injected near tumors could be strongly absorbed by tumor cells. The numbers of endothelial cells and blood vessels were significantly increased in tumor tissues treated with exosomes compared to control tissues. Furthermore, to reveal the mechanism underlying exosome-mediated angiogenesis in retinoblastoma, we analyzed the levels of 12 microRNAs in the exosomes. Specifically, our data showed that miR-92a-3p was enriched in RB exosomes. Accordingly, miR-92a-3p was increased in the HUVECs incubated with these exosomes. After treatment with a miR-92a-3p inhibitor, the promoting effect of exosomes on the migration and tube formation of HUVECs was significantly abrogated. The expression of the angiogenesis-related genes mentioned above was markedly decreased in HUVECs. Similarly, treatment with a microRNA mimic also demonstrated that miR-92a-3p was involved in the angiogenesis of HUVECs. More importantly, bioinformatics analysis predicted that Krüppel-like factor 2 (KLF2), a member of the KLF family of zinc-finger transcription factors, might be an active target of miR-92a-3p. Notably, this prediction was confirmed both in vitro and in vivo. Thus, our work suggests that exosomal miR-92a-3p is involved in tumor angiogenesis and might be a promising therapeutic candidate for retinoblastoma.

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The Functional Implications of Endothelial Gap Junctions and Cellular Mechanics in Vascular Angiogenesis

Cancers ◽

10.3390/cancers11020237 ◽

2019 ◽

Vol 11 (2) ◽

pp. 237 ◽

Cited By ~ 15

Author(s):

Takayuki Okamoto ◽

Haruki Usuda ◽

Tetsuya Tanaka ◽

Koichiro Wada ◽

Motomu Shimaoka

Keyword(s):

Endothelial Cells ◽

Cell Migration ◽

Gap Junctions ◽

Gap Junction ◽

Cancer Cells ◽

Tumor Development ◽

Tube Formation ◽

Cellular Mechanics

Angiogenesis—the sprouting and growth of new blood vessels from the existing vasculature—is an important contributor to tumor development, since it facilitates the supply of oxygen and nutrients to cancer cells. Endothelial cells are critically affected during the angiogenic process as their proliferation, motility, and morphology are modulated by pro-angiogenic and environmental factors associated with tumor tissues and cancer cells. Recent in vivo and in vitro studies have revealed that the gap junctions of endothelial cells also participate in the promotion of angiogenesis. Pro-angiogenic factors modulate gap junction function and connexin expression in endothelial cells, whereas endothelial connexins are involved in angiogenic tube formation and in the cell migration of endothelial cells. Several mechanisms, including gap junction function-dependent or -independent pathways, have been proposed. In particular, connexins might have the potential to regulate cell mechanics such as cell morphology, cell migration, and cellular stiffness that are dynamically changed during the angiogenic processes. Here, we review the implication for endothelial gap junctions and cellular mechanics in vascular angiogenesis.

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Thrombin promotes endothelial cell alignment in Matrigel in vitro and angiogenesis in vivo

AJP Cell Physiology ◽

10.1152/ajpcell.1997.273.1.c239 ◽

1997 ◽

Vol 273 (1) ◽

pp. C239-C245 ◽

Cited By ~ 110

Author(s):

G. C. Haralabopoulos ◽

D. S. Grant ◽

H. K. Kleinman ◽

M. E. Maragoudakis

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Specific Inhibitor ◽

Fold Increase ◽

Inflammatory Cells ◽

Tube Formation ◽

Cell Alignment ◽

Promoting Effect

We have tested the effect of thrombin on endothelial cell tube formation in vitro and angiogenesis in vivo. Thrombin induces the differentiation of endothelial cells into capillary structures in a dose-dependent fashion (0.1-0.3 units thrombin/ml) on Matrigel, a laminin-rich reconstituted basement membrane matrix. At higher thrombin concentrations (1.0 unit/ml), a suppression of tube formation is evident, probably due to downregulation (desensitization) of the thrombin receptor. D-Phe-Pro-Arg-CH2Cl-thrombin is without effect when used alone, but it abolishes the tube-promoting effect of thrombin when used in combination with thrombin, indicating the involvement of the catalytic site of thrombin. Activation of protein kinase C (PKC) seems to be the transduction mechanism involved in the stimulation of tube formation by thrombin. Ro-318220 (3 micrograms/ml), a specific inhibitor of PKC, completely abolishes the stimulatory effect of thrombin. In the in vivo Matrigel system of angiogenesis, there is a 10-fold increase in endothelial cell infiltration in response to thrombin. These results provide evidence for the angiogenesis-promoting effect of thrombin in vivo and the induction by thrombin of the angiogenic phenotype of endothelial cells in vitro in the absence of other cell types such as smooth muscle cells, pericytes, and inflammatory cells.

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The COL-4A1 polypeptide destroy endothelial cells through the TGF-β/PI3K/AKT pathway

Scientific Reports ◽

10.1038/s41598-021-94801-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ting Li ◽

Zhonghui Ling ◽

Kaipeng Xie ◽

Yixiao Wang ◽

Zhijing Miao ◽

...

Keyword(s):

Endothelial Cells ◽

Rat Model ◽

Vascular Endothelial Cells ◽

Underlying Mechanism ◽

Tube Formation ◽

Cell Counting ◽

Akt Pathway ◽

Control Group

AbstractPreeclampsia (PE) is commonly considered as a placental disorder in pregnancy. Until now, the etiology and pathological mechanism of PE have remained ambiguous. Although PE can lead to a variety of maternal and infant complications, there are still no effective treatments. This study aimed to explore the correlation between the novel polypeptide COL-4A1 and PE, and to identify the underlying mechanism by which this polypeptide may function and to explore new therapeutic targets for PE. A rat model of PE was established and used to verify the function of the polypeptide COL-4A1 in vivo. Additionally, human umbilical vascular endothelial cells (HUVECs) were cultured with or without COL-4A1 and TNF-α (20 ng/ml). Cell Counting Kit-8 (CCK-8), wound-healing, Transwell and tube formation assays were used to evaluate cell proliferation, migration and angiopoiesis. RNA sequencing and mass spectrometry were conducted to explore the underlying downstream mechanism of COL-4A1. In vivo, COL-4A1 increased blood pressure and elevated the risk of fetal growth restriction (FGR) which was induced by lipopolysaccharide (LPS) in the rat model. In vitro, COL-4A1 significantly inhibited the proliferation and migration of HUVECs. After culture with COL-4A1, compared to control group the adhesive ability and level of reactive oxygen species (ROS) were enhanced and tube formation ability was decreased. Furthermore, Western blotting (WB) and pull-down assays were conducted to explore the underlying mechanism by which COL-4A1 functions, and the TGF-β/PI3K/AKT pathway was identified as the potential pathway involved in its effects. In summary, these results revealed that the polypeptide COL-4A1 caused PE-like symptoms in cells and a rat model. Through the TGF-β/PI3K/AKT pathway, COL-4A1 interferes with the pathogenesis of PE. Thus COL-4A1 is expected to become a potential target of PE, providing a basis for exploring the treatment of PE.

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The recombinant lectin-like domain of thrombomodulin inhibits angiogenesis through interaction with Lewis Y antigen

Blood ◽

10.1182/blood-2011-08-376038 ◽

2012 ◽

Vol 119 (5) ◽

pp. 1302-1313 ◽

Cited By ~ 31

Author(s):

Cheng-Hsiang Kuo ◽

Po-Ku Chen ◽

Bi-Ing Chang ◽

Meng-Chen Sung ◽

Chung-Sheng Shi ◽

...

Keyword(s):

Endothelial Cells ◽

Egf Receptor ◽

Tube Formation ◽

Endothelial Tube Formation ◽

A Cell ◽

Lewis Y ◽

Tm Domain

AbstractLewis Y Ag (LeY) is a cell-surface tetrasaccharide that participates in angiogenesis. Recently, we demonstrated that LeY is a specific ligand of the recombinant lectin-like domain of thrombomodulin (TM). However, the biologic function of interaction between LeY and TM in endothelial cells has never been investigated. Therefore, the role of LeY in tube formation and the role of the recombinant lectin-like domain of TM—TM domain 1 (rTMD1)—in antiangiogenesis were investigated. The recombinant TM ectodomain exhibited lower angiogenic activity than did the recombinant TM domains 2 and 3. rTMD1 interacted with soluble LeY and membrane-bound LeY and inhibited soluble LeY-mediated chemotaxis of endothelial cells. LeY was highly expressed on membrane ruffles and protrusions during tube formation on Matrigel. Blockade of LeY with rTMD1 or Ab against LeY inhibited endothelial tube formation in vitro. Epidermal growth factor (EGF) receptor in HUVECs was LeY modified. rTMD1 inhibited EGF receptor signaling, chemotaxis, and tube formation in vitro, and EGF-mediated angiogenesis and tumor angiogenesis in vivo. We concluded that LeY is involved in vascular endothelial tube formation and rTMD1 inhibits angiogenesis via interaction with LeY. Administration of rTMD1 or recombinant adeno-associated virus vector carrying TMD1 could be a promising antiangiogenesis strategy.

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Accutin, a New Disintegrin, Inhibits Angiogenesis In Vitro and In Vivo by Acting as Integrin vβ3 Antagonist and Inducing Apoptosis

Blood ◽

10.1182/blood.v92.9.3268 ◽

1998 ◽

Vol 92 (9) ◽

pp. 3268-3276 ◽

Cited By ~ 90

Author(s):

Chia Hsin Yeh ◽

Hui-Chin Peng ◽

Tur-Fu Huang

Keyword(s):

Endothelial Cells ◽

Umbilical Vein ◽

Fluorescein Isothiocyanate ◽

Adenosine Diphosphate ◽

Tube Formation ◽

Platelet Glycoprotein ◽

Dependent Manner ◽

Antiangiogenic Effect

Abstract Endothelial integrins play an essential role in angiogenesis and cell survival. Accutin, a new member of disintegrin family derived from venom of Agkistrodon acutus, potently inhibited human platelet aggregation caused by various agonists (eg, thrombin, collagen, and, adenosine diphosphate [ADP]) through the blockade of fibrinogen binding to platelet glycoprotein IIb/IIIa (ie, integrin IIbβ3). In this report, we describe that accutin specifically inhibited the binding of monoclonal antibody (MoAb) 7E3, which recognizes integrin vβ3, to human umbilical vein endothelial cells (HUVECs), but not those of other anti-integrin MoAbs such as 2β1, 3β1, and 5β1. Moreover, accutin, but not the control peptide GRGES, dose-dependently inhibited the 7E3 interaction with HUVECs. Both 7E3 and GRGDS, but not GRGES or Integrelin, significantly blocked fluorescein isothiocyanate-conjugated accutin binding to HUVEC. In functional studies, accutin exhibited inhibitory effects on HUVEC adhesion to immobilized fibrinogen, fibronectin and vitronectin, and the capillary-like tube formation on Matrigel in a dose- and RGD-dependent manner. In addition, it exhibited an effective antiangiogenic effect in vivo when assayed by using the 10-day-old embryo chick CAM model. Furthermore, it potently induced HUVEC apoptotic DNA fragmentation as examined by electrophoretic and flow cytometric assays. In conclusion, accutin inhibits angiogenesis in vivo and in vitro by blocking integrin vβ3 of endothelial cells and by inducing apoptosis. The antiangiogenic activity of disintegrins might be explored as the target of developing the potential antimetastatic agents. © 1998 by The American Society of Hematology.

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Necroptosis regulates tumor repopulation after radiotherapy via RIP1/RIP3/MLKL/JNK/IL8 pathway

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-019-1423-5 ◽

2019 ◽

Vol 38 (1) ◽

Cited By ~ 5

Author(s):

Yiwei Wang ◽

Minghui Zhao ◽

Sijia He ◽

Yuntao Luo ◽

Yucui Zhao ◽

...

Keyword(s):

Colorectal Cancer ◽

Growth Stimulation ◽

Underlying Mechanism ◽

Promoting Effect ◽

Clinical Prognosis ◽

Associated Proteins ◽

Radiation Induced ◽

Colorectal Cancer Patients

Abstract Background Tumor cell repopulation after radiotherapy is a major cause for the tumor radioresistance and recurrence. This study aims to investigate the underlying mechanism of tumor repopulation after radiotherapy, with focus on whether and how necroptosis takes part in this process. Methods Necroptosis after irradiation were examined in vitro and in vivo. And the growth-promoting effect of necroptotic cells was investigated by chemical inhibitors or shRNA against necroptosis associated proteins and genes in in vitro and in vivo tumor repopulation models. Downstream relevance factors of necroptosis were identified by western blot and chemiluminescent immunoassays. Finally, the immunohistochemistry staining of identified necroptosis association growth stimulation factor was conducted in human colorectal tumor specimens to verify the relationship with clinical outcome. Results Radiation-induced necroptosis depended on activation of RIP1/RIP3/MLKL pathway, and the evidence in vitro and in vivo demonstrated that the inhibition of necroptosis attenuated growth-stimulating effects of irradiated tumor cells on living tumor reporter cells. The JNK/IL-8 were identified as downstream molecules of pMLKL during necroptosis, and inhibition of JNK, IL-8 or IL-8 receptor significantly reduced tumor repopulation after radiotherapy. Moreover, the high expression of IL-8 was associated with poor clinical prognosis in colorectal cancer patients. Conclusions Necroptosis associated tumor repopulation after radiotherapy depended on activation of RIP1/RIP3/MLKL/JNK/IL-8 pathway. This novel pathway provided new insight into understanding the mechanism of tumor radioresistance and repopulation, and MLKL/JNK/IL-8 could be developed as promising targets for blocking tumor repopulation to enhance the efficacy of colorectal cancer radiotherapy.

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Evaluation of Angiogenesis Assays

Biomedicines ◽

10.3390/biomedicines7020037 ◽

2019 ◽

Vol 7 (2) ◽

pp. 37 ◽

Cited By ~ 14

Author(s):

Zachary I. Stryker ◽

Mehdi Rajabi ◽

Paul J. Davis ◽

Shaker A. Mousa

Keyword(s):

Endothelial Cells ◽

Tube Formation ◽

Angiogenic Activity ◽

In Vitro Methods ◽

Current State ◽

Angiogenesis Process ◽

Pertinent Information ◽

Exogenous Factors

Angiogenesis assays allow for the evaluation of pro- or anti-angiogenic activity of endogenous or exogenous factors (stimulus or inhibitors) through investigation of their pro-or anti- proliferative, migratory, and tube formation effects on endothelial cells. To model the process of angiogenesis and the effects of biomolecules on that process, both in vitro and in vivo methods are currently used. In general, in vitro methods monitor specific stages in the angiogenesis process and are used for early evaluations, while in vivo methods more accurately simulate the living microenvironment to provide more pertinent information. We review here the current state of angiogenesis assays as well as their mechanisms, advantages, and limitations.

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Cardioprotective Activity of Selected Polyphenols Based on Epithelial and Aortic Cell Lines. A Review

Molecules ◽

10.3390/molecules25225343 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5343

Author(s):

Michał Otręba ◽

Leon Kośmider ◽

Jerzy Stojko ◽

Anna Rzepecka-Stojko

Keyword(s):

Endothelial Cells ◽

Tube Formation ◽

Health Claims ◽

In Vivo Studies ◽

Positive Effects ◽

Endothelial Tube Formation ◽

Disease Therapy ◽

Species Production

Polyphenols have recently gained popularity among the general public as products and diets classified as healthy and containing naturally occurring phenols. Many polyphenolic extracts are available on the market as dietary supplements, functional foods, or cosmetics, taking advantage of clients’ desire to live a healthier and longer life. However, due to the difficulty of discovering the in vivo functions of polyphenols, most of the research focuses on in vitro studies. In this review, we focused on the cardioprotective activity of different polyphenols as possible candidates for use in cardiovascular disease therapy and for improving the quality of life of patients. Thus, the studies, which were mainly based on endothelial cells, aortic cells, and some in vivo studies, were analyzed. Based on the reviewed articles, polyphenols have a few points of action, including inhibition of acetylcholinesterase, decrease in reactive oxygen species production and endothelial tube formation, stimulation of acetylcholine-induced endothelium-derived mediator release, and others, which lead to their cardio- and/or vasoprotective effects on endothelial cells. The obtained results suggest positive effects of polyphenols, but more long-term in vivo studies demonstrating effects on mechanism of action, sensitivity, and specificity or efficacy are needed before legal health claims can be made.

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DEPTOR Deficiency-Mediated mTORc1 Hyperactivation in Vascular Endothelial Cells Promotes Angiogenesis

Cellular Physiology and Biochemistry ◽

10.1159/000488619 ◽

2018 ◽

Vol 46 (2) ◽

pp. 520-531 ◽

Cited By ~ 7

Author(s):

Yan Ding ◽

Lanlan Shan ◽

Wenqing Nai ◽

Xiaojun Lin ◽

Ling Zhou ◽

...

Keyword(s):

Endothelial Cells ◽

Signaling Pathway ◽

Molecular Mechanisms ◽

Gene Knockout ◽

Umbilical Vein ◽

Vascular Endothelial Cell ◽

Tube Formation ◽

Vascular Endothelial

Background/Aims: The mechanistic target of rapamycin (mTOR) signaling pathway is essential for angiogenesis and embryonic development. DEP domain-containing mTOR-interacting protein (DEPTOR) is an mTOR binding protein that functions to inhibit the mTOR pathway In vitro experiments suggest that DEPTOR is crucial for vascular endothelial cell (EC) activation and angiogenic responses. However, knowledge of the effects of DEPTOR on angiogenesis in vivo is limited. This study aimed to determine the role of DEPTOR in tissue angiogenesis and to elucidate the molecular mechanisms. Methods: Cre/loxP conditional gene knockout strategy was used to delete the Deptor gene in mouse vascular ECs. The expression or distribution of cluster of differentiation 31 (CD31), vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1 alpha (HIF-1α) were detected by immunohistochemical staining or western blot. Tube formation assay was used to measure angiogenesis in vitro. Results: Deptor knockdown led to increased expression of CD31, VEGF and HIF-1α in heart, liver, kidney and aorta. After treatment with rapamycin, their expression was significantly down regulated. In vitro, human umbilical vein endothelial cells (HUVECs) were transfected with DEPTOR-specific small interfering RNA (siRNA), which resulted in a significant increase in endothelial tube formation and migration rates. In contrast, DEPTOR overexpression markedly reduced the expression of CD31, VEGF and HIF-1α. Conclusions: Our findings demonstrated that deletion of the Deptor gene in vascular ECs resulted in upregulated expression of CD31 and HIF-1α, and further stimulated the expression of VEGF which promoted angiogenesis, indicating that disruption of normal angiogenic pathways may occur through hyperactivation of the mTORC1/HIF-1α/VEGF signaling pathway.

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