Effect of hypoxia on the expression of genes encoding insulin-like growth factors and some related proteins in U87 glioma cells without IRE1 function

AbstractObjective. The aim of the present study was to investigate the effect of hypoxia on the expression of genes encoding insulin-like growth factors (IGF1 and IGF2), their receptor (IGF1R), binding protein-4 (IGFBP4), and stanniocalcin 2 (STC2) in U87 glioma cells in relation to inhibition of endoplasmic reticulum stress signaling mediated by IRE1 (inositol requiring enzyme 1) for evaluation of their possible significance in the control of tumor growth. Methods. The expression of IGF1, IGF2, IGF1R, IGFBP4, and STC2 genes in U87 glioma cells transfected by empty vector pcDNA3.1 (control) and cells without IRE1 signaling enzyme function (transfected by dnIRE1) upon hypoxia was studied by qPCR. Results. The expression of IGF1 and IGF2 genes is down-regulated in glioma cells without IRE1 signaling enzyme function in comparison with the control cells. At the same time, the expression of IGF1R, IGFBP4, and STC2 genes was up-regulated in glioma cells upon inhibition of IRE1, with more significant changes for IGFBP4 and STC2 genes. We also showed that hypoxia does not change significantly the expression of IGF1, IGF2, and IGF1R genes but up-regulated IGFBP4 and STC2 genes expression in control glioma cells. Moreover, the inhibition of both enzymatic activities (kinase and endoribonuclease) of IRE1 in glioma cells does not change significantly the effect of hypoxia on the expression of IGF1, IGF1R, and IGFBP4 genes but introduces sensitivity of IGF2 gene to hypoxic condition. Thus, the expression of IGF2 gene is resistant to hypoxia only in control glioma cells and significantly down-regulated in cells without functional activity of IRE1 signaling enzyme, which is central mediator of the unfolded protein response and an important component of the tumor growth as well as metabolic diseases. Conclusions. Results of this study demonstrate that the expression of IGF1 and IGF1R genes is resistant to hypoxic condition both in control U87 glioma cells and cells without IRE1 signaling enzyme function. However, hypoxia significantly up-regulates the expression of IGFBP4 gene independently on the inhibition of IRE1 enzyme. These data show that proteins encoded by these genes are resistant to hypoxia except IGFBP4 and participate in the regulation of metabolic and proliferative processes through IRE1 signaling.

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Hypoxic regulation of the expression of genes encoded estrogen related proteins in U87 glioma cells: eff ect of IRE1 inhibition

Endocrine Regulations ◽

10.1515/enr-2017-0002 ◽

2017 ◽

Vol 51 (1) ◽

pp. 8-19 ◽

Cited By ~ 7

Author(s):

Minchenko Do ◽

Riabovol Oo ◽

Ratushna Oo ◽

Minchenko Oh

Keyword(s):

Endoplasmic Reticulum ◽

Endoplasmic Reticulum Stress ◽

Quantitative Polymerase Chain Reaction ◽

Glioma Cells ◽

Hypoxic Condition ◽

Enzyme Function ◽

Unfolded Protein ◽

Expression Of Genes ◽

The Unfolded Protein Response ◽

Related Proteins

Abstract Objective. The aim of the present study was to examine the effect of inhibition of endoplasmic reticulum stress signaling, mediated by IRE1 (inositol requiring enzyme 1), which is a central mediator of the unfolded protein response on the expression of genes encoded estrogen related proteins (NRIP1/RIP140, TRIM16/EBBP, ESRRA/NR3B1, FAM162A/E2IG5, PGRMC2/PMBP, and SLC39A6/LIV-1) and their hypoxic regulation in U87 glioma cells for evaluation of their possible significance in the control of glioma cells proliferation.Methods. The expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells, transfected by empty vector pcDNA3.1 (control) and cells without IRE1 signaling enzyme function (transfected by dnIRE1) upon hypoxia, was studied by a quantitative polymerase chain reaction.Results. Inhibition of both enzymatic activities (kinase and endoribonuclease) of IRE1 signaling enzyme function up-regulates the expression of EBBP, E2IG5, PGRMC2, and SLC39A6 genes is in U87 glioma cells in comparison with the control glioma cells, with more significant changes for E2IG5 and PGRMC2 genes. At the same time, the expression of NRIP1 and ESRRA genes is strongly down-regulated in glioma cells upon inhibition of IRE1. We also showed that hypoxia increases the expression of E2IG5, PGRMC2, and EBBP genes and decreases NRIP1 and ESRRA genes expression in control glioma cells. Furthermore, the inhibition of IRE1 in U87 glioma cells decreases the eff ect of hypoxia on the expression of E2IG5 and PGRMC2 genes, eliminates hypoxic regulation of NRIP1 gene, and enhances the sensitivity of ESRRA gene to hypoxic condition. Furthermore, the expression of SLC39A6 gene is resistant to hypoxia in both the glioma cells with and without IRE1 signaling enzyme function.Conclusions. Results of this investigation demonstrate that inhibition of IRE1 signaling enzyme function affects the expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells in gene specific manner and these changes possibly contribute to the suppression of the cell proliferation. Most of these genes are regulated by hypoxia and preferentially through IRE1 signaling pathway of endoplasmic reticulum stress.

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Factors and their receptor genes in glioma cells with suppressed function of ERN 1 enzyme upon glucose deprivation

Bulletin of Taras Shevchenko National University of Kyiv Series Problems of Physiological Functions Regulation ◽

10.17721/2616_6410.2016.20.44-49 ◽

2016 ◽

Vol 20 (1) ◽

pp. 44-49

Author(s):

A. Kharkova ◽

O. Minchenko

Keyword(s):

Gene Expression ◽

Glioma Cells ◽

Glucose Deprivation ◽

Expression Level ◽

Enzyme Function ◽

Gene Expressions ◽

Igf2 Gene ◽

Igf Receptor ◽

Effect Of Glucose ◽

Insulin Like Growth Factors

It was shown that the expression level of insulin like growth factors (IGF1 and IGF2) genes is decreased, but IGF receptor (IRF1R) gene is significantly increased in U87 glioma cells with suppressed activity of the sensor and signaling enzyme ERN1. In U87 glioma cells the expression level of IGF1 gene is decreased but IGF2 and IGF1R do not change significantly upon glucose deprivation condition. The inhibition of ERN1 functional activity does not affect the sensitivity of IGF1 and IGF1R gene expressions to glucose deprivation but the inhibition of ERN1 eliminates the effect of glucose deprivation on IGF2 gene expression. Thus, the IGF1, IGF2 and IGF1R genes are related to the regulation of glioma cells proliferation and are sensitive to glucose deprivation in dependence of ERN1 enzyme function.

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Inhibition of IRE1 signaling affects the expression of genes encoded glucocorticoid receptor and some related factors and their hypoxic regulation in U87 glioma cells

Endocrine Regulations ◽

10.1515/enr-2016-0014 ◽

2016 ◽

Vol 50 (3) ◽

pp. 127-136 ◽

Cited By ~ 2

Author(s):

D.O. Minchenko ◽

O.O. Riabovol ◽

D.O. Tsymbal ◽

O.O. Ratushna ◽

O.H. Minchenko

Keyword(s):

Endoplasmic Reticulum ◽

Endoplasmic Reticulum Stress ◽

Glucocorticoid Receptor ◽

Quantitative Polymerase Chain Reaction ◽

Glioma Cells ◽

Hypoxic Condition ◽

Enzyme Function ◽

Related Factors ◽

Expression Of Genes ◽

Glioma Growth

Abstract Objective. The aim of the present investigation was to examine the effect of inhibition of endoplasmic reticulum stress signaling, mediated by IRE1 (inositol requiring enzyme 1), which is a central mediator of the unfolded protein response on the expression of genes encoding glucocorticoid receptor (NR3C1) and some related proteins (SGK1, SGK3, NCOA1, NCOA2, ARHGAP35, NNT) and their hypoxic regulation in U87 glioma cells for evaluation of their possible significance in the control of the glioma growth. Methods. The expression of NR3C1,SGK1,SGK3, NCOA1, NCOA2, ARHGAP35, and NNT genes in U87 glioma cells, transfected by empty vector pcDNA3.1 (control) and cells without IRE1 signaling enzyme function (transfected by dnIRE1) upon hypoxia, was studied by quantitative polymerase chain reaction. Results. Inhibition of IRE1 signaling enzyme function up-regulates the expression of NR3C1, SGK1, NCOA1, NCOA2, ARHGAP35, and NNT genes in U87 glioma cells in comparison with the control glioma cells, with more significant changes for NR3C1, SGK1, and NNT genes. At the same time, the expression of SGK3 gene is strongly down-regulated in glioma cells upon inhibition of IRE1. We have also shown that hypoxia increases the expression of NR3C1, SGK1, NCOA2, ARHGAP35, and NNT genes but decreases SGK3 and NCOA1 genes expression in control glioma cells. Moreover, the inhibition of both enzymatic activities (kinase and endoribonuclease) of IRE1 in U87 glioma cells enhances the eff ect of hypoxia on the expression of SGK1, SGK3, and NNT genes, but decreases the sensitivity of NR3C1 gene to hypoxic condition. Furthermore, the expression of NCOA1 gene is resistant to hypoxia in control glioma cells, but NCOA2 and ARHGAP35 genes are resistant to this condition in glioma cells without functional activity of IRE1 signaling enzyme. Conclusions. Results of this investigation demonstrate that inhibition of IRE1 signaling enzyme function affects the expression of NR3C1, SGK1, SGK3, NCOA1, NCOA2, ARHGAP35, and NNT genes in U87 glioma cells in gene specific manner and that all these genes are regulated by hypoxia preferentially through IRE1 signaling pathway of the endoplasmic reticulum stress.

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STK11 (LKB1) missense somatic mutant isoforms promote tumor growth, motility and inflammation

Communications Biology ◽

10.1038/s42003-020-1092-0 ◽

2020 ◽

Vol 3 (1) ◽

Cited By ~ 2

Author(s):

Paula Granado-Martínez ◽

Sara Garcia-Ortega ◽

Elena González-Sánchez ◽

Kimberley McGrail ◽

Rafael Selgas ◽

...

Keyword(s):

Tumor Growth ◽

Somatic Mutations ◽

Human Cancer ◽

Tumor Biology ◽

Missense Mutations ◽

Expression Of Genes ◽

Promote Tumor Growth ◽

Genes Encoding ◽

Differential Gene ◽

Somatic Mutant

AbstractElucidating the contribution of somatic mutations to cancer is essential for personalized medicine. STK11 (LKB1) appears to be inactivated in human cancer. However, somatic missense mutations also occur, and the role/s of these alterations to this disease remain unknown. Here, we investigated the contribution of four missense LKB1 somatic mutations in tumor biology. Three out of the four mutants lost their tumor suppressor capabilities and showed deficient kinase activity. The remaining mutant retained the enzymatic activity of wild type LKB1, but induced increased cell motility. Mechanistically, LKB1 mutants resulted in differential gene expression of genes encoding vesicle trafficking regulating molecules, adhesion molecules and cytokines. The differentially regulated genes correlated with protein networks identified through comparative secretome analysis. Notably, three mutant isoforms promoted tumor growth, and one induced inflammation-like features together with dysregulated levels of cytokines. These findings uncover oncogenic roles of LKB1 somatic mutations, and will aid in further understanding their contributions to cancer development and progression.

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RhoGDIα-dependent balance between RhoA and RhoC is a key regulator of cancer cell tumorigenesis

Molecular Biology of the Cell ◽

10.1091/mbc.e11-01-0020 ◽

2011 ◽

Vol 22 (17) ◽

pp. 3263-3275 ◽

Cited By ~ 23

Author(s):

T. T. Giang Ho ◽

Audrey Stultiens ◽

Johanne Dubail ◽

Charles M. Lapière ◽

Betty V. Nusgens ◽

...

Keyword(s):

Tumor Growth ◽

Cancer Progression ◽

Dynamic Balance ◽

Cellular Functions ◽

Expression Of Genes ◽

Genes Encoding ◽

Interfering Rna

RhoGTPases are key signaling molecules regulating main cellular functions such as migration, proliferation, survival, and gene expression through interactions with various effectors. Within the RhoA-related subclass, RhoA and RhoC contribute to several steps of tumor growth, and the regulation of their expression affects cancer progression. Our aim is to investigate their respective contributions to the acquisition of an invasive phenotype by using models of reduced or forced expression. The silencing of RhoC, but not of RhoA, increased the expression of genes encoding tumor suppressors, such as nonsteroidal anti-inflammatory drug–activated gene 1 (NAG-1), and decreased migration and the anchorage-independent growth in vitro. In vivo, RhoC small interfering RNA (siRhoC) impaired tumor growth. Of interest, the simultaneous knockdown of RhoC and NAG-1 repressed most of the siRhoC-related effects, demonstrating the central role of NAG-1. In addition of being induced by RhoC silencing, NAG-1 was also largely up-regulated in cells overexpressing RhoA. The silencing of RhoGDP dissociation inhibitor α (RhoGDIα) and the overexpression of a RhoA mutant unable to bind RhoGDIα suggested that the effect of RhoC silencing is indirect and results from the up-regulation of the RhoA level through competition for RhoGDIα. This study demonstrates the dynamic balance inside the RhoGTPase network and illustrates its biological relevance in cancer progression.

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Acute renal failure. III. The role of growth factors in the process of renal regeneration and repair

AJP Renal Physiology ◽

10.1152/ajprenal.2000.279.1.f3 ◽

2000 ◽

Vol 279 (1) ◽

pp. F3-F11 ◽

Cited By ~ 73

Keyword(s):

Renal Failure ◽

Acute Renal Failure ◽

Growth Factors ◽

Experimental Models ◽

Future Research ◽

Expression Of Genes ◽

Genes Encoding ◽

Renal Regeneration ◽

General Studies

This review, which is the final installment in a series devoted to controversial issues in acute renal failure (ARF) (3, 47), will examine available information regarding the role of growth factors in ARF. In general, studies in this area have fallen into two broad categories: 1) those that have examined the renal expression of genes encoding growth factors or transcriptional factors associated with the growth response that is induced after ARF, and 2) those that have examined the efficacy of exogenously administered growth factors in accelerating recovery of renal function in experimental models of ARF. Despite the vast amount of information that has accumulated in these two areas of investigation, our understanding of the mechanisms involved in the process of regeneration and repair after ARF, and the role of growth factors in this response, remains rudimentary. This overview, contributed to by a number of experts in the field, is designed to summarize present knowledge and to highlight potentially fertile areas for future research in this area.

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Insulin receptor substrate 1 gene expression is strongly up-regulated by HSPB8 silencing in U87 glioma cells

Endocrine Regulations ◽

10.2478/enr-2020-0026 ◽

2020 ◽

Vol 54 (4) ◽

pp. 231-243

Author(s):

Oksana S. Hnatiuk ◽

Dariia O. Tsymbal ◽

Dmytro O. Minchenko ◽

Olena O. Khita ◽

Yulia M. Viletska ◽

...

Keyword(s):

Insulin Receptor ◽

Quantitative Polymerase Chain Reaction ◽

Glioma Cells ◽

Insulin Receptor Substrate ◽

Gene Expressions ◽

Insulin Receptor Substrate 1 ◽

Expression Of Genes ◽

Genes Encoding ◽

The Stability ◽

Related Proteins

Abstract Objective. 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. Methods. Silencing of HSPB8 mRNA was introduced by HSPB8 specific siRNA. The expression level of HSPB8, IRS1, HK2, GLO1, HOMER3, MYL9, NAMPT, PER2, PERP, GADD45A, and DEK genes was studied in U87 glioma cells by quantitative polymerase chain reaction. Results. It was shown that silencing of HSPB8 mRNA by specific to HSPB8 siRNA led to a strong down-regulation of this mRNA and significant modification of the expression of IRS1 and many other genes in glioma cells: strong up-regulated of HOMER3, GLO1, and PERP and down-regulated of MYL9, NAMPT, PER2, GADD45A, and DEK gene expressions. At the same time, no significant changes were detected in the expression of HK2 gene in glioma cells treated by siRNA, specific to HSPB8. Moreover, the silencing of HSPB8 mRNA enhanced the glioma cells proliferation rate. Conclusions. Results of this investigation demonstrated that silencing of HSPB8 mRNA affected the expression of IRS1 gene as well as many other genes encoding tumor growth related proteins. It is possible that the dysregulation of most of the studied genes in glioma cells after silencing of HSPB8 is reflected by a complex of intergenic interactions and that this polyfunctional chaperone is an important factor for the stability of genome function and regulatory mechanisms contributing to the tumorigenesis control.

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