Publications by authors named "Oleksandr Minchenko"

Nanographene oxide (nGO) nanoparticles (NPs) have unique properties and are widely used in various fields, including biomedicine. These NPs, however, also exhibit toxic ef-fects and therefore, the understanding of the molecular mechanism of nGO toxicity is very im-portant mainly for the nanomedicine, especially the cancer therapy. This study aimed to examine the impact of nGO NPs on the expression of genes associated with endoplasmic reticulum (ER) stress, proliferation, and cancerogenesis in both normal human astrocytes and U87MG glioblas-toma cells.

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Carboxypeptidase E (CPE) plays an important role in the biosynthesis of neurotransmitters and peptide hormones including insulin. It also promotes cell proliferation, survival, and invasion of tumor cells. The endoplasmic reticulum stress, hypoxia, and nutrient supply are significant factors of malignant tumor growth including glioblastoma.

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Background: Endoplasmic reticulum stress and synthesis of serine are essential for tumor growth, but the mechanism of their interaction is not clarified yet. The overarching goal of this work was to investigate the impact of ERN1 (endoplasmic reticulum to nucleus signaling 1) inhibition on the expression of serine synthesis genes in U87MG glioblastoma cells concerning the suppression of cell proliferation.

Methods: Wild type U87MG glioblastoma cells and their clones with overexpression of transgenes dnERN1 (without cytoplasmic domain of ERN1) and dnrERN1 (with mutation in endoribonuclease of ERN1), and empty vector (as control) were used.

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Background: The ERN1 (endoplasmic reticulum to nucleus signaling 1) pathway plays an important role in the regulation of gene expression in glioblastoma, but molecular mechanism has not yet been fully elucidated. The aim of this study was to evaluate the relative relevance of ERN1 activity as a kinase in comparison to its endoribonuclease activity in the regulation of homeobox gene expression.

Methods: Two sublines of U87MG glioblastoma cells with different ways of ERN1 inhibition were used: dnERN1 (overexpressed transgene without protein kinase and endoribonuclease) and dnrERN1 (overexpressed transgene with mutation in endoribonuclease).

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Serine hydroxymethyltransferase (SHMT2) plays a multifunctional role in mitochondria (folate-dependent tRNA methylation, translation, and thymidylate synthesis). The endoplasmic reticulum stress, hypoxia, and glucose and glutamine supply are significant factors of malignant tumor growth including glioblastoma. Previous studies have shown that the knockdown of the endoplasmic reticulum to nucleus signaling 1 (ERN1) pathway of endoplasmic reticulum stress strongly suppressed glioblastoma cell proliferation and modified the sensitivity of these cells to hypoxia and glucose or glutamine deprivations.

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Glucose and glutamine supply as well as serine synthesis and endoplasmic reticulum (ER) stress are important factors of glioblastoma growth. Previous studies showed that the knockdown of ERN1 (ER to nucleus signaling 1) suppressed glioblastoma cell proliferation and modified the sensitivity of numerous gene expressions to nutrient deprivations. The present study is aimed to investigate the impact of glucose and glutamine deprivations on the expression of serine synthesis genes in U87MG glioblastoma cells in relation to ERN1 knockdown with the intent to reveal the role of ERN1 signaling pathway on the ER stress-dependent regulation of these gene expressions.

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Objective.: Homeobox genes play an important role in health and disease including oncogenesis. The present investigation aimed to study ERN1-dependent hypoxic regulation of the expression of genes encoding homeobox proteins MEIS (zinc finger E-box binding homeobox 2) and LIM homeobox 1 family, SPAG4 (sperm associated antigen 4) and NKX3-1 (NK3 homeobox 1) in U87MG glioblastoma cells in response to inhibition of ERN1 (endoplasmic reticulum to nucleus signaling 1) for evaluation of their possible significance in the control of glioblastoma growth.

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Glucocorticoids are important stress-responsive regulators of insulin-dependent metabolic processes realized through specific changes in genome function. The aim of this study was to investigate the impact of cortisol on insulin receptor and related genes expression in HEK293 cells upon induction the endoplasmic reticulum (ER) stress by tunicamycin and hypoxia. The human embryonic kidney cell line HEK293 was used.

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Serine synthesis as well as endoplasmic reticulum stress and hypoxia are important factors of malignant tumor growth including glioblastoma. Previous studies have shown that the knockdown of ERN1 (endoplasmic reticulum to nucleus signaling) significantly suppressed the glioblastoma cell proliferation and modified the hypoxia regulation. The present study is aimed to investigate the impact of hypoxia on the expression of (phosphoglycerate dehydrogenase), (phosphoserine aminotransferase 1), (phosphoserine phosphatase), (activating transcription factor 4), and (serine hydroxymethyltransferase 1) in U87MG glioblastoma cells in relation to knockdown of ERN1 with the intent to reveal the role of ERN1 signaling pathway on the endoplasmic reticulum stress-dependent regulation of expression of these genes.

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Single-walled carbon nanotubes (SWCNTs) are considered to be one of the nanomaterials attractive for biomedical applications, particularly in the health sciences as imaging probes and drug carriers, especially in the field of cancer therapy. The increasing exploitation of nanotubes necessitates a comprehensive evaluation of the potential impact of these nanomaterials, which purposefully accumulate in the cell nucleus, on the human health and the function of the genome in the normal and tumor tissues. The aim of this study was to investigate the sensitivity of the expression of and some other genes associated with the endoplasmic reticulum (ER) stress and cell proliferation to low doses of SWCNTs in normal human astrocytes (NHA/TS) and glioblastoma cells (U87MG) with and without an inhibition of ERN1 signaling pathway of the ER stress.

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Homeobox genes play a fundamental role in the embryogenesis, but some of them have been linked to oncogenesis. The present study is aimed to investigate the impact of glucose and glutamine deprivations on the expression of homeobox genes such as (paired box 6), ( homeobox 3), (PBX homeobox interacting protein 1), ( homeobox 1), and in ERN1 knockdown U87 glioma cells with the intent to reveal the role of ERN1 (endoplasmic reticulum to nucleus signaling 1) signaling pathway on the endoplasmic reticulum stress dependent regulation of homeobox genes. The control (transfected by empty vector) and ERN1 knockdown (transfected by dominant-negative ERN1) U87 glioma cells were exposed to glucose and glutamine deprivations for 24 h.

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The aim of the present study was to investigate the expression of pyruvate dehydrogenase genes such as PDHA1, PDHB, DLAT, DLD, and PDHX in U87 glioma cells in response to glutamine and glucose deprivations in control glioma cells and endoplasmic reticulum to nucleus signaling 1 (ERN1) knockdown cells, the major endoplasmic reticulum (ER) stress signaling pathway, to find out whether there exists a possible dependence of these important regulatory genes expression on both glutamine and glucose supply as well as ERN1 signaling. The expression level of PDHA1, PDHB, DLAT, DLD, and PDHX genes was studied by real-time quantitative polymerase chain reaction in control U87 glioma cells (transfected by empty vector) and cells with inhibition of ERN1(transfected by dnERN1) after cells exposure to glucose and glutamine deprivations. The data showed that the expression level of PDHA1, PDHB, DLAT, and DLD genes was down-regulated (more profound in PDHB gene) in control glioma cells treated with glutamine deprivation.

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Nanographene oxide, an oxidation derivative of graphene, is considered to be one of the nanomaterials attractive for biomedical applications, although this nanomaterial is toxic. The increasing exploitation of graphene-based materials necessitates a comprehensive evaluation of the potential impact of these materials on the human health. Moreover, it is necessary to investigate in detail the mechanisms of its toxic effect on living cells particularly at the genome level.

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Single-walled carbon nanotubes (SWCNTs) are able to cross the blood-brain barrier, penetrate through the cell membrane, and accumulate in the cell nucleus, which purposefully allows their use in the health sciences as imaging probes and drug carriers in the cancer therapy. The aim of this study was to investigate the effect of low doses of SWCNTs on the expression of microRNAs associated with the cell proliferation and the brain development in zebrafish () embryos. The zebrafish embryos (72 h post fertilization) were exposed to low doses of SWCNTs (2 and 8 ng/ml of medium) for 24 or 72 h.

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The unique properties of single-walled carbon nanotubes (SWCNTs) make them viable candidates for versatile implementation in the biomedical devices. They are able to cross the blood-brain barrier, enter cells and accumulate in cell nuclei. We studied the effect of these carbon nanoparticles on the expression of genes associated with endoplasmic reticulum stress and proliferation, cell viability and cancerogenesis as well as microRNAs in normal human astrocytes.

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The aim of the present investigation was to study the impact of glucose and gluta-mine deprivations on the expression of genes encoding EDN1 (endothelin-1), its cognate receptors (EDNRA and EDNRB), and ECE1 (endothelin converting enzyme 1) in U87 glioma cells in response to knockdown of ERN1 (endoplasmic reticulum to nucleus signaling 1), a major signaling pathway of endoplasmic reticulum stress, for evaluation of their possible implication in the control of glioma growth through ERN1 and nutrient limitations. The expression level of EDN1, its receptors and converting enzyme 1 in control U87 glioma cells and cells with knockdown of ERN1 treated by glucose or glutamine deprivation by quantitative polymerase chain reaction was studied. We showed that the expression level of and genes was significantly up-regulated in control U87 glioma cells exposure under glucose deprivation condition in comparison with the glioma cells, growing in regular glucose containing medium.

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The aim of the present investigation was to study the expression of genes encoding IRS1 (insulin receptor substrate 1) and some other functionally active proteins in U87 glioma cells under silencing of polyfunctional chaperone HSPB8 for evaluation of the possible significance of this protein in intergenic interactions. Silencing of HSPB8 mRNA was introduced by HSPB8 specific siRNA. The expression level of , , , , , , , , , , and genes was studied in U87 glioma cells by quantitative polymerase chain reaction.

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Nano-titanium nitride (Nano-TiN) has strong resistance to wear and corrosion, good biocompatibility, and an attractive metallic luster. Nano-TiN is widely used in medical devices, such as orthopedic implants, syringe needles, coronary stents, and long-term dental implants, and also in imitation gold jewelry. Despite its widespread use, there are few reports describing safety evaluations of Nano-TiN.

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Objective: The aim of the present investigation was to study the expression of genes encoding homeobox proteins ZEB2 (zinc finger E-box binding homeobox 2), TGIF1 (TGFB induced factor homeobox 1), SPAG4 (sperm associated antigen 4), LHX1 (LIM homeobox 1), LHX2, LHX6, NKX3-1 (NK3 homeobox 1), and PRRX1 (paired related homeobox 1) in U87 glioma cells in response to glucose deprivation in control glioma cells and cells with knockdown of ERN1 (endoplasmic reticulum to nucleus signaling 1), the major pathway of the endoplasmic reticulum stress signaling, for evaluation of it possible significance in the control of glioma growth through ERN1 signaling and chemoresistance.

Methods: The expression level of homeobox family genes was studied in control (transfected by vector) and ERN1 knockdown U87 glioma cells under glucose deprivation condition by real-time quantitative polymerase chain reaction.

Results: It was shown that the expression level of ZEB2, TGIF1, PRRX1, and LHX6 genes was up-regulated in control glioma cells treated by glucose deprivation.

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Objective: The aim of the present investigation was to study the expression of genes encoding polyfunctional proteins insulinase (insulin degrading enzyme, IDE) and pitrilysin metallopeptidase 1 (PITRM1) in U87 glioma cells in response to inhibition of endoplasmic reticulum stress signaling mediated by ERN1/IRE1 (endoplasmic reticulum to nucleus signaling 1) for evaluation of their possible significance in the control of metabolism through ERN1 signaling as well as hypoxia, glucose and glutamine deprivations.

Methods: The expression level of IDE and PITRM1 genes was studied in control and ERN1 knockdown U87 glioma cells under glucose and glutamine deprivations as well as hypoxia by quantitative polymerase chain reaction.

Results: It was found that the expression level of IDE and PITRM1 genes was down-regulated in ERN1 knockdown (without ERN1 protein kinase and endoribonuclease activity) glioma cells in comparison with the control glioma cells, being more significant for PITRM1 gene.

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Objective: The aim of the present study was to investigate the effect of adipokine NAMPT (nicotinamide phosphoribosyltransferase) silencing on the expression of genes encoding IRS1 (insulin receptor substrate 1) and some other proliferation related proteins in U87 glioma cells for evaluation of the possible significance of this adipokine in intergenic interactions.

Methods: The silencing of NAMPT mRNA was introduced by NAMPT specific siRNA. The expression level of NAMPT, IGFBP3, IRS1, HK2, PER2, CLU, BNIP3, TPD52, GADD45A, and MKI67 genes was studied in U87 glioma cells by quantitative polymerase chain reaction.

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Objective: The aim of the present study was to examine the effect of glucose deprivation on the expression of genes encoded glucocorticoid receptor (NR3C1) and some related proteins (NR3C2, AHR, NRIP1, NNT, ARHGAP35, SGK1, and SGK3) in U87 glioma cells in response to inhibition of endoplasmic reticulum stress signaling mediated by ERN1/IRE1 (endoplasmic reticulum to nucleus signaling 1/inositol requiring enzyme 1) for evaluation of their possible significance in the control of glioma growth through endoplasmic reticulum stress signaling mediated by IRE1 and glucose deprivation.

Methods: The expression of NR3C1, NR3C2, AHR, NRIP1, NNT, ARHGAP35, SGK1, and SGK3 genes in U87 glioma cells transfected by empty vector pcDNA3.1 (control cells) and cells without ERN1 signaling enzyme function (transfected by dnERN1) under glucose deprivation was studied by real time quantitative polymerase chain reaction.

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Objective: The aim of the present investigation was to study the effect of hypoxia on the expression of genes encoding endothelin-1 (EDN1) and its cognate receptors (EDNRA and EDNRB) as well as endothelin converting enzyme 1 (ECE1) in U87 glioma cells in response to inhibition of endoplasmic reticulum stress signaling mediated by ERN1/IRE1 (endoplasmic reticulum to nucleus signaling 1) for evaluation of their possible significance in the control of glioma growth through ERN1 and hypoxia.

Methods: The expression level of EDN1, EDNRA, EDNRB, and ECE1 genes as well as micro-RNA miR-19, miR-96, and miR-206 was studied in control and ERN1 knockdown U87 glioma cells under hypoxia by quantitative polymerase chain reaction.

Results: It was shown that the expression level of EDN1, EDNRA, EDNRB, and ECE1 genes was up-regulated in ERN1 knockdown glioma cells in comparison with the control glioma cells, being more significant for endothelin-1.

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Objective: The development of obesity and its metabolic complications is associated with dys-regulation of various intrinsic mechanisms, which control basic metabolic processes via changes in the expression of numerous regulatory genes. The main goal of this work was to study the association between the expression of insulin-like growth factors (IGF1 and IGF2) and IGF-binding proteins and insulin resistance in obese adolescents for evaluation of possible contribution of these genes in development of insulin resistance.

Methods: The expression of IGF1, IGF2, and IGFBPs mRNA was measured in blood of obese adolescents with normal insulin sensitivity and insulin resistance in comparison with the normal (control) individuals.

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The effect of single-walled carbon nanotubes (SWCNTs) on the expression of a subset of immune response, apoptosis and cell proliferation -associated genes was studied in normal human astrocytes (line NHA/TS). In the cells treated with SWCNTs (2, 10 and 50 ng/ml of medium for 24 h) we observed a strong dose-dependent down-regulation of the expression of a cell surface glycoproteins HLA-DRA (major histocompatibility complex, class II, DR alpha) and HLA-DRB1. At the same time, the expression of HLA-F (major histocompatibility complex, class I, F), LMNB1 (lamin B1), and HTRA1 (high temperature requirement A1) genes as well as the level of miR-190b and miR-7 was up-regulated in NHA/TS subjected to different concentrations of SWCNTs.

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