Tag Archives: angiogenesis

miR-329-containing exosomes derived from breast tumor cells suppress VEGF and KDM1A expression in endothelial cells

N. Maleki1,2,3*, F. Karami1, S. Heyati2, M. HadiZadeh3, Gh. Parnian4*

1Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Islamic Azad University-Tehran North Branch, Tehran, Iran;
*e-mail: dr.nargesmaleki@yahoo.com;
2Gynecology and reproductive biology Department, Kowsar poly-clinic, Tehran, Iran;
3Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran;
4Appletree Medical group, 275 Dundad W (Grange), Toronto, Ontario, Canada;
*e-mail: ghazalehparnian1@gmail.com

Received: 03 February 2021; Accepted: 07 July 2021

The exosomal transfer of miRNAs from tumor cells is considered to modulate VEGF expression and angiogenesis in endothelial cells. The aim of our investigation was to focus exclusively on the ability of specific exosomal miR329 to regulate angiogenesis within breast tumor. All experiments were done on MCF-7 and HUVEC cell lines. Exosomes were derived from MCF-7 cells both untreated and treated with tamoxifen that is an effecrive suppressor of hormone receptor-positive breast cancer. The level of miR32 and its targeted genes VEGF and lysine (K)-specific demethylase 1A (KDM1A) expression was estimated with q-RT-PCR. The PKH26 red fluorescent labeling kit was used to label the isolated exosomes and monitor their uptake. It was shown that the relative amount of miR-329 in exosomes was twice as large as in breast cancer  cells. Fluorescence microscopy imaging presented that exosomes from  MCF-7 cells were able to penetrate into endothelial cells and concentrate in the cytoplasm. It was observed that exosomes derived from untreated breast cancer cells induced KDM1A and VEGF gene expressions whereas exosomes from tamoxifen-treated cancer cells induced time-dependent decrease of KDM1A and VEGF expression in endothelial cells. It is assumed that the transfer of miR-329 containing exosomes from tamoxifen treated breast cancer cells to the endothelial cells could repress angiogenic molecular signaling pathway and be used as a supplementary strategy in breast cancer treatment.

Vitamin D(3) regulates hepatic VEGF-A and apelin expression in experimental type 1 diabetes

D. O. Labudzynskyi1*, I. O. Shymanskyi1, O. O. Lisakovska1,
A. O. Mazanova1, L. V. Natrus2, M. M. Veliky1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Bogomolets National Medical University, Kyiv, Ukraine;
*e-mail: konsument3@gmail.com

Received: 09 July 2019; Accepted: 15 May 2020

The deficiency of vitamin D is associated with the risk of various chronic diseases, including diabetes mellitus and its complications. Given the strong genomic action of vitamin D hormone-active form, its deficiency can lead to dysfunction of cytokine signaling pathways, including those dependent on vascular endothelial growth factors (VEGFs) and apelin. The present study was carried out to define the link between VEGF-A and apelin expression in liver, hepatocytes viability and vitamin D status at experimental type 1 diabetes in mice. We established that chronic hyperglycemia at streptozotocin-induced diabetes was accompanied by a 2.2-fold decrease in 25OHD content in the serum and increased hepatocytes apoptosis and necrosis. Vitamin D deficiency correlated with increased apelin and VEGF-A (8- and 1.6-fold respectively) expression. Almost complete restoration of circulatory 25OHD content in serum was achieved at vitamin D3 treatment (800 IU/kg, per os, for 2 months) followed by reduced apelin and VEGF-A expression in liver and the decline of hepatocytes apoptosis. We conclude that vitamin D3 can be involved in cell survival, angiogenesis and fibrogenesis by modulating  VEGF-A and apelin dependent regulatory systems in diabetic liver.

Plasminogen modulates formation and release of platelet angiogenic regulators

A. A. Tykhomyrov, D. D. Zhernosekov, T. V. Grinenko

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: artem_tykhomyrov@ukr.net

Received: 19 July 2019; Accepted: 29 November 2019

Platelets store, produce and release a variety of angiogenesis regulators, which can contribute to both normal tissue repair and angiopathy-associated pathologies. Plasminogen has been earlier shown to regulate some platelet functions, but if it is able to modulate angiogenic capacities of platelets is still poorly studied. Thus, the aim of the present study was to evaluate the effects of different plasminogen forms on the formation and secretion of angiogenic protein regulators by platelets. Human washed platelets were obtained by gel-filtration on Sepharose-2B. The levels of P-selectin (CD-62P) exposed on the plasma membrane of untreated and activated platelets was monitored by flow cytometry. Secretion of platelet-derived vascular endothelial growth factor (VEGF) as well as plasminogen fragmentation and angiostatin formation by intact platelets and platelet plasma membranes were analyzed by immunoblotting. It was shown that thrombin or collagen exposure resulted in enhanced P-selectin surface expression by platelets, while Lys-form of plasminogen reduced agonist-induced platelet secretion. Lys-plasminogen, but not Glu-form, inhibited agonist-induced VEGF release from platelets. Activation of platelets significantly accelerated plasminogen cleavage and angiostatin formation. Anti-actin antibodies inhibited plasminogen fragmentation during incubation with platelet plasma membranes indicating surface-exposed actin participation  in plasminogen conversion to angiostatins. The present study uncovers a novel function of plasminogen to limit angiogenic potential of platelets via angiostatin formation and inhibition of VEGF secretion.

The mechanism of VEGF-mediated endothelial cells survival and proliferation in conditions of unfed-culture

T. V. Nikolaienko, V. V. Nikulina, D. V. Shelest, L. V. Garmanchuk

Educational and Scientific Centre “Institute of Biology”,
Taras Shevchenko National University of Kyiv, Ukraine;
e-mail: nikolaenkotetiana@yandex.ua

The mechanisms of VEGF-mediated effects on endothelial cells during cancer development and progression is not clear. In present study the biological effects of VEGF, VEGF-rich culture medium of peritoneal macrophages from mice with Lewis lung carcinoma were studied on MAEC cell line under conditions of unfed culture. We have shown that VEGF increased cell proliferation by the 5th day of culturing vs control and anti-VEGF-treated cells. This effect was associated with increased consumption of glucose and NO production by the 2nd day while decreased – on the 5th day of cell culturing. VEGF-mediated NO production was dependent on Ca2+ ions. Block of Ca2+-channels (LaCl3) had more pronounced inhibitory effect vs chelator of Ca2+ ions (EDTA).  It was shown that peritoneal macrophages are the main suppliers of VEGF at tumor angiogenesis, as evidenced by the data obtained on model system of endothelial cells synchronized in G0/G1 phase.

Role of plasminogen/plasmin in functional activity of blood cells

D. D. Zhernossekov, E. I. Yusova, T. V. Grinenko

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;

The article deals with the data concerning structural peculiarities of plasminogen/plasmin molecule, which define the specificity of intermolecular interactions and provide the variety of its biological functions. The main principles of the modern classification of plasminogen receptors and factors, which modulate their expression, have been presented. We have considered the mechanisms regulating both plasmin formation and activity on the surface of cells, fibrin and proteins of extracellular matrix. The data of previous investigators and our own results, concerning the influence of plasminogen/plasmin on platelet aggregation induced by different agonists, have been summarized. The participation of plasminogen/plasmin in atherogenesis and angiogenesis mediated­ by endotheliocyte receptors has been discussed. Special attention was given to plasminogen/plasmin pro-inflammatory function, which is realized by regulatory processes of activation, secretion, migration and apoptosis of monocytes and macrophages.

Role of multidomain structure of urokinase in regulation of growth and remodeling of vessels

V. A. Tkachuk1,2, O. S. Plekhanova1, I. B. Beloglazova1, E. V. Parfenova1

1Russian Cardiologic Research-Production Complex,
RF Ministry of Public Health, Moscow, Russia;
2Faculty of Fundamental Medicine, M.V. Lomonosov Moscow
State University, Russia;
e-mail: plekhanova@mail.ru

Urokinase type plasminogen activator, or urokinase (uPA), is a multifunctional protein which plays special regulatory role in the vascular wall and can actuate the proteolytic and signal cascades. The authors’ results and literature data concerning the role of urokinase in remodeling blood vessels and angiogenesis are summarized in the paper. At the present stage urokinase may be conside­red as a promising target for the effects directed to prophylaxis of restenoses, to preventing of negative remodeling of arteries­, stimulation of vessels growth under the ischemic diseases and suppression of angiogenesis under oncologic diseases.

Plasminogen and angiostatin levels in female benign breast lesions

A. A. Tykhomyrov1, I. L. Vovchuk2, T. V. Grinenko1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Odessa I. I. Mechnikov National University, Ukraine;
e-mail: artem_tykhomyrov@ukr.net

It is known that benign breast tissue exhibit relatively low angiogenic capacity. Activation of angiogenesis in mammary pre-malignant lesions could be associated with disease progression and high risk of transformation into the breast cancer. However, insight into the underlying molecular mechanisms involved in angiogenesis regulation in non-cancerous breast pathologies is still poorly defined. The purpose of the present study was to determine levels of plasminogen and its proteolytic fragments (angiostatins) in mammary dysplasia (mastopathy and breast cyst) and benign neoplasms (fibroadenomas). Plasminogen and angiostatins were analyzed using immunoblotting and quantified by densitometric scanning. The significant increase in plasminogen levels was found in fibrocystic, cysts, and non-proliferatious fibroadenoma masses (4.7-, 3.7-, and 3.5-fold, respectively) compared to healthy breast tissues (control). In the same benign lesions, 6.7-, 4-, and 3.7-fold increase in plasminogen 50 kDa fragment (angiostatin) levels as compared with control were also observed. Activation of matrix metalloproteinase-9, which was detected using gelatine zymography, could be responsible for plasminogen cleavage and abundance of angiostatin in fibrocystic and cyst masses. In contrast, dramatic decrease of both plasminogen and angiostatin levels (3.8- and 5.3-folds, respectively) was shown in tissues of proliferatious form of fibroadenoma in comparison with that of the dormant type of this neoplasm. Based on the obtained results, we concluded that angiostatin, a potent vessel growth inhibitor and anti-inflammatory molecule, can play a crucial role in pathophysiology of non-cancerous breast diseases. Further studies are needed to evaluate potential diagnostic and clinical implications of these proteins for prediction and therapy of benign breast pathologies.