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The P2X7 receptor is a key modulator of the PI3K/GSK3β/VEGF signaling network: evidence in experimental neuroblastoma. Oncogene 2015; 34:5240-51. [PMID: 25619831 DOI: 10.1038/onc.2014.444] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/21/2014] [Accepted: 12/01/2014] [Indexed: 02/06/2023]
Abstract
Neuroblastoma (NB) is an aggressive pediatric tumor, responsible for 15% of cancer-related deaths in childhood, lacking an effective treatment in its advanced stages. The P2X7 receptor for extracellular ATP was associated to NB cell proliferation and recently emerged as a promoter of tumor engraftment, growth and vascularization. In an effort to identify new therapeutic options for neuroblastoma, we studied the role of P2X7 receptor in NB biology. We first analyzed the effect of P2X7 activation or down-modulation of the main biochemical ways involved in NB progression: the PI3K/Akt/GSK3β/MYCN and the HIF1α/VEGF pathways. In ACN human NB cells, P2X7 stimulation enhanced PI3K/Akt, while decreasing GSK3β activity. In the same model, P2X7 silencing or antagonist administration reduced the activity of PI3K/Akt and increased that of GSK3β, leading to a decrease in cellular glycogen stores. Similarly, P2X7 downmodulation caused a reduction in HIF1α levels and vascular endothelial growth factor (VEGF) secretion. Systemic administration of two different P2X7 antagonists (AZ10606120 or A740003) in nude/nude mice reduced ACN-derived tumor growth. An even stronger effect of P2X7 blockade was obtained in a syngeneic immune-competent neuroblastoma model: Neuro2A cells injected in AlbinoJ mice. Together with tumor regression, treatment with P2X7 antagonists caused downmodulation of the Akt/HIF1α axis, leading to reduced VEGF content and decreased vessel formation. Interestingly, in both experimental models, P2X7 antagonists strongly reduced the expression of the probably best-accepted oncogene in NB: MYCN. Finally, we associated P2X7 overexpression with poor prognosis in advanced-stage NB patients. Taken together, our data suggest that P2X7 receptor is an upstream regulator of the main signaling pathways involved in NB growth, metabolic activity and angiogenesis, and a promising therapeutic target for neuroblastoma treatment.
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252
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Age-related proteostasis and metabolic alterations in Caspase-2-deficient mice. Cell Death Dis 2015; 6:e1615. [PMID: 25611376 PMCID: PMC4669765 DOI: 10.1038/cddis.2014.567] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 11/27/2014] [Indexed: 12/21/2022]
Abstract
Ageing is a complex biological process for which underlying biochemical changes are still largely unknown. We performed comparative profiling of the cellular proteome and metabolome to understand the molecular basis of ageing in Caspase-2-deficient (Casp2−/−) mice that are a model of premature ageing in the absence of overt disease. Age-related changes were determined in the liver and serum of young (6–9 week) and aged (18–24 month) wild-type and Casp2−/− mice. We identified perturbed metabolic pathways, decreased levels of ribosomal and respiratory complex proteins and altered mitochondrial function that contribute to premature ageing in the Casp2−/− mice. We show that the metabolic profile changes in the young Casp2−/− mice resemble those found in aged wild-type mice. Intriguingly, aged Casp2−/− mice were found to have reduced blood glucose and improved glucose tolerance. These results demonstrate an important role for caspase-2 in regulating proteome and metabolome remodelling during ageing.
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253
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Kang SW, Lee S, Lee EK. ROS and energy metabolism in cancer cells: alliance for fast growth. Arch Pharm Res 2015; 38:338-45. [PMID: 25599615 DOI: 10.1007/s12272-015-0550-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 01/05/2015] [Indexed: 10/24/2022]
Abstract
In normal cells, the cellular reactive oxygen species (ROS) level is proportional to the activity of mitochondrial electron transport and tightly controlled by endogenous antioxidant system. However, energy metabolism and ROS homeostasis in cancer cells are much different from those in normal cells. For example, a majority of cellular glucose is metabolized through aerobic glycolysis ("Warburg effect") and the pentose phosphate pathway. Cancer cells harbor functional mitochondria, but many mutations in nuclear DNA-encoded mitochondrial genes and mitochondrial genome result in the mitochondrial metabolic reprogramming. The other characteristic of cancer cells is to maintain much higher ROS level than normal cells. Ironically, cancer cells overexpress the ROS-producing NADPH oxidase and the ROS-eliminating antioxidant enzymes, both of which enzyme systems share NADPH as a reducing power source. In this article, we review the complex connection between ROS and energy metabolisms in cancer cells.
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Affiliation(s)
- Sang Won Kang
- Department of Life Sciences, Research Center for Cell Homeostasis, Ewha Womans University, Seoul, 120-750, Republic of Korea,
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254
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PFKFB4 controls embryonic patterning via Akt signalling independently of glycolysis. Nat Commun 2015; 6:5953. [PMID: 25601028 DOI: 10.1038/ncomms6953] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 11/26/2014] [Indexed: 12/25/2022] Open
Abstract
How metabolism regulators play roles during early development remains elusive. Here we show that PFKFB4 (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4), a glycolysis regulator, is critical for controlling dorsal ectoderm global patterning in gastrulating frog embryos via a non-glycolytic function. PFKFB4 is required for dorsal ectoderm progenitors to proceed towards more specified fates including neural and non-neural ectoderm, neural crest or placodes. This function is mediated by Akt signalling, a major pathway that integrates cell homeostasis and survival parameters. Restoring Akt signalling rescues the loss of PFKFB4 in vivo. In contrast, glycolysis is not essential for frog development at this stage. Our study reveals the existence of a PFKFB4-Akt checkpoint that links cell homeostasis to the ability of progenitor cells to undergo differentiation, and uncovers glycolysis-independent functions of PFKFB4.
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255
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Abstract
PURPOSE OF REVIEW Proline metabolism impacts a number of regulatory targets in both animals and plants and is especially important in cancer. Glutamine, a related amino acid, is considered second in importance only to glucose as a substrate for tumors. But proline and glutamine are interconvertible and linked in their metabolism. In animals, proline and glutamine have specific regulatory functions and their respective physiologic sources. A comparison of the metabolism of proline and glutamine would help us understand the importance of these two nonessential amino acids in cancer metabolism. RECENT FINDINGS The regulatory functions of proline metabolism proposed 3 decades ago have found relevance in many areas. For cancer, these functions play a role in apoptosis, autophagy and in response to nutrient and oxygen deprivation. Importantly, proline-derived reactive oxygen species served as a driving signal for reprogramming. This model has been applied by others to metabolic regulation for the insulin-prosurvival axis, induction of adipose triglyceride lipase for lipid metabolism and regulation of embryonic stem cell development. Of special interest, modulatory proteins such as parkinson protein 7 and oral cancer overexpressed 1 interact with pyrroline-5-carboxylate reductase, a critical component of the proline regulatory axis. Although the interconvertibility of proline and glutamine has been long established, recent findings showed that the proto-oncogene, cellular myelocytomatosis oncogene, upregulates glutamine utilization (glutaminase) and routes glutamate to proline biosynthesis (pyrroline-5-carboxylate synthase, pyrroline-5-carboxylate reductases). Additionally, collagen, which contains large amounts of proline, may be metabolized to serve as a reservoir for proline. This metabolic relationship as well as the new regulatory targets of proline metabolism invites an elucidation of the differential effects of these nonessential amino acids and their production, storage and mobilization. SUMMARY Mechanisms by which the proline regulatory axis modulates the cancer phenotype are being revealed. Proline can be synthesized from glutamine as well as derived from collagen degradation. The metabolism of proline serves as a source of energy during stress, provides signaling reactive oxygen species for epigenetic reprogramming and regulates redox homeostasis.
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Affiliation(s)
- James M Phang
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, Maryland, USA
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256
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Hunter RW, Zeqiraj E, Morrice N, Sicheri F, Sakamoto K. Expression and purification of functional human glycogen synthase-1:glycogenin-1 complex in insect cells. Protein Expr Purif 2014; 108:23-29. [PMID: 25527037 PMCID: PMC4370744 DOI: 10.1016/j.pep.2014.12.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/07/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
GYS1:GN1 complex expressed using bicistronic pFastBac-Dual vector in insect cells. A large quantity of highly-pure stoichiometric GYS1:GN1 complex obtained. Purified GYS1 is functional and heavily phosphorylated at several Ser/Thr residues. GYS1:GN1 complex will be useful to reveal its structural and biochemical properties.
We report the successful expression and purification of functional human muscle glycogen synthase (GYS1) in complex with human glycogenin-1 (GN1). Stoichiometric GYS1:GN1 complex was produced by co-expression of GYS1 and GN1 using a bicistronic pFastBac™-Dual expression vector, followed by affinity purification and subsequent size-exclusion chromatography. Mass spectrometry analysis identified that GYS1 is phosphorylated at several well-characterised and uncharacterised Ser/Thr residues. Biochemical analysis, including activity ratio (in the absence relative to that in the presence of glucose-6-phosphate) measurement, covalently attached phosphate estimation as well as phosphatase treatment, revealed that recombinant GYS1 is substantially more heavily phosphorylated than would be observed in intact human or rodent muscle tissues. A large quantity of highly-pure stoichiometric GYS1:GN1 complex will be useful to study its structural and biochemical properties in the future, which would reveal mechanistic insights into its functional role in glycogen biosynthesis.
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Affiliation(s)
- Roger W Hunter
- Nestlé Institute of Health Sciences SA, EPFL Innovation Park, bâtiment G, 1015 Lausanne, Switzerland
| | - Elton Zeqiraj
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
| | - Nicholas Morrice
- Beatson Institute for Cancer Research, Bearsden, Glasgow G61 1BD, UK
| | - Frank Sicheri
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada; Departments of Biochemistry and Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Kei Sakamoto
- Nestlé Institute of Health Sciences SA, EPFL Innovation Park, bâtiment G, 1015 Lausanne, Switzerland.
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257
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Bishop T, Ratcliffe PJ. Signaling hypoxia by hypoxia-inducible factor protein hydroxylases: a historical overview and future perspectives. HYPOXIA 2014; 2:197-213. [PMID: 27774477 PMCID: PMC5045067 DOI: 10.2147/hp.s47598] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
By the early 1900s, the close matching of oxygen supply with demand was recognized to be a fundamental requirement for physiological function, and multiple adaptive responses to environment hypoxia had been described. Nevertheless, the widespread operation of mechanisms that directly sense and respond to levels of oxygen in animal cells was not appreciated for most of the twentieth century with investigators generally stressing the regulatory importance of metabolic products. Work over the last 25 years has overturned that paradigm. It has revealed the existence of a set of “oxygen-sensing” 2-oxoglutarate dependent dioxygenases that catalyze the hydroxylation of specific amino acid residues and thereby control the stability and activity of hypoxia-inducible factor. The hypoxia-inducible factor hydroxylase pathway regulates a massive transcriptional cascade that is operative in essentially all animal cells. It transduces a wide range of responses to hypoxia, extending well beyond the classical boundaries of hypoxia physiology. Here we review the discovery and elucidation of these pathways, and consider the opportunities and challenges that have been brought into focus by the findings, including new implications for the integrated physiology of hypoxia and therapeutic approaches to ischemic/hypoxic disease.
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Affiliation(s)
- Tammie Bishop
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
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258
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Zois CE, Favaro E, Harris AL. Glycogen metabolism in cancer. Biochem Pharmacol 2014; 92:3-11. [PMID: 25219323 DOI: 10.1016/j.bcp.2014.09.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 08/29/2014] [Accepted: 09/04/2014] [Indexed: 12/30/2022]
Abstract
Since its identification more than 150 years ago, there has been an extensive characterisation of glycogen metabolism and its regulatory pathways in the two main glycogen storage organs of the body, i.e. liver and muscle. In recent years, glycogen metabolism has also been demonstrated to be upregulated in many tumour types, suggesting it is an important aspect of cancer cell pathophysiology. Here, we provide an overview of glycogen metabolism and its regulation, with a focus on its role in metabolic reprogramming of cancer cells. The various methods to detect glycogen in tumours in vivo are also reviewed. Finally, we discuss the targeting of glycogen metabolism as a strategy for cancer treatment.
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Affiliation(s)
- Christos E Zois
- Molecular Oncology Laboratories, Oxford University, Department of Oncology, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford OX3 9DS, United Kingdom.
| | - Elena Favaro
- Cell Death and Metabolism, Danish Cancer Society Research Center, Strandboulevarden 49, 2100 Copenhagen, Denmark.
| | - Adrian L Harris
- Molecular Oncology Laboratories, Oxford University, Department of Oncology, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford OX3 9DS, United Kingdom.
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259
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Somsák L, Bokor É, Czibere B, Czifrák K, Koppány C, Kulcsár L, Kun S, Szilágyi E, Tóth M, Docsa T, Gergely P. Synthesis of C-xylopyranosyl- and xylopyranosylidene-spiro-heterocycles as potential inhibitors of glycogen phosphorylase. Carbohydr Res 2014; 399:38-48. [DOI: 10.1016/j.carres.2014.05.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/26/2014] [Accepted: 05/28/2014] [Indexed: 11/28/2022]
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260
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Bentaib A, De Tullio P, Chneiweiss H, Hermans E, Junier MP, Leprince P. Metabolic reprogramming in transformed mouse cortical astrocytes: A proteomic study. J Proteomics 2014; 113:292-314. [PMID: 25305589 DOI: 10.1016/j.jprot.2014.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Revised: 09/02/2014] [Accepted: 09/22/2014] [Indexed: 11/29/2022]
Abstract
Metabolic reprogramming is thought to play a key role in sustaining the survival and proliferation of cancer cells. These changes facilitate for example the uptake and release of nutrients required for nucleotide, protein and lipid synthesis necessary for macromolecule assembly and tumor growth. We applied a 2D-DIGE (two-dimensional differential in-gel electrophoresis) quantitative proteomic analysis to characterize the proteomes of mouse astrocytes that underwent in vitro cancerous transformation, and of their normal counterparts. Metabolic reprogramming effects on enzymatic and structural protein expression as well as associated metabolites abundance were quantified. Using enzymatic activity measurements and zymography, we documented and confirmed several changes in abundance and activity of various isoenzymes likely to participate in metabolic reprogramming. We found that after transformation, the cells increase their expression of glycolytic enzymes, thus augmenting their ability to use aerobic glycolysis (Warburg effect). An increased capacity to dispose of reducing equivalents through lactate production was also documented. Major effects on carbohydrates, amino acids and nucleotides metabolic enzymes were also observed. Conversely, the transformed cells reduced their enzymatic capacity for reactions of tricarboxylic acid oxidation, for neurotransmitter (glutamate) metabolism, for oxidative stress defense and their expression of astroglial markers. BIOLOGICAL SIGNIFICANCE The use of a global approach based on a 2D DIGE analysis allows obtaining a comprehensive view of the metabolic reprogramming undergone by astrocytes upon cancerous transformation. Indeed, except for a few enzymes such as pyruvate carboxylase and glutaminase that were not detected in our initial analysis, pertinent information on the abundance of most enzymes belonging to pathways relevant to metabolic reprogramming was directly obtained. In this in vitro model, transformation causes major losses of astrocyte-specific proteins and functions and the acquisition of metabolic adaptations that favor intermediate metabolites production for increased macromolecule biosynthesis. Thus our approach appears to be readily applicable for the investigation of changes in protein abundance that determine various transformed cell phenotypes. It could similarly be applied to the evaluation of the effects of treatments aimed at correcting the consequences of cell transformation.
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Affiliation(s)
| | - Pascal De Tullio
- Pharmaceutical chemistry, Department of Pharmacy, University of Liège, Liège, Belgium
| | - Hervé Chneiweiss
- Glial Plasticity and Cerebral Tumors, UMR8246 CNRS/U1130 Inserm/ UMCR18, Université Pierre et Marie Curie, Paris, France
| | - Emmanuel Hermans
- Institute of Neurosciences, Group of Neuropharmacology, Université Catholique de Louvain, Brussels, Belgium
| | - Marie-Pierre Junier
- Glial Plasticity and Cerebral Tumors, UMR8246 CNRS/U1130 Inserm/ UMCR18, Université Pierre et Marie Curie, Paris, France
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261
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Roberts DJ, Miyamoto S. Hexokinase II integrates energy metabolism and cellular protection: Akting on mitochondria and TORCing to autophagy. Cell Death Differ 2014; 22:248-57. [PMID: 25323588 DOI: 10.1038/cdd.2014.173] [Citation(s) in RCA: 276] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 09/11/2014] [Accepted: 09/15/2014] [Indexed: 01/08/2023] Open
Abstract
Accumulating evidence reveals that metabolic and cell survival pathways are closely related, sharing common signaling molecules. Hexokinase catalyzes the phosphorylation of glucose, the rate-limiting first step of glycolysis. Hexokinase II (HK-II) is a predominant isoform in insulin-sensitive tissues such as heart, skeletal muscle, and adipose tissues. It is also upregulated in many types of tumors associated with enhanced aerobic glycolysis in tumor cells, the Warburg effect. In addition to the fundamental role in glycolysis, HK-II is increasingly recognized as a component of a survival signaling nexus. This review summarizes recent advances in understanding the protective role of HK-II, controlling cellular growth, preventing mitochondrial death pathway and enhancing autophagy, with a particular focus on the interaction between HK-II and Akt/mTOR pathway to integrate metabolic status with the control of cell survival.
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Affiliation(s)
- D J Roberts
- Department of Pharmacology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, USA
| | - S Miyamoto
- Department of Pharmacology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, USA
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262
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Chettimada S, Joshi SR, Alzoubi A, Gebb SA, McMurtry IF, Gupte R, Gupte SA. Glucose-6-phosphate dehydrogenase plays a critical role in hypoxia-induced CD133+ progenitor cells self-renewal and stimulates their accumulation in the lungs of pulmonary hypertensive rats. Am J Physiol Lung Cell Mol Physiol 2014; 307:L545-56. [PMID: 25063801 PMCID: PMC7199226 DOI: 10.1152/ajplung.00303.2013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 07/22/2014] [Indexed: 12/25/2022] Open
Abstract
Although hypoxia is detrimental to most cell types, it aids survival of progenitor cells and is associated with diseases like cancer and pulmonary hypertension in humans. Therefore, understanding the underlying mechanisms that promote survival of progenitor cells in hypoxia and then developing novel therapies to stop their growth in hypoxia-associated human diseases is important. Here we demonstrate that the proliferation and growth of human CD133(+) progenitor cells, which contribute to tumorigenesis and the development of pulmonary hypertension, are increased when cultured under hypoxic conditions. Furthermore, glucose-6-phosphate dehydrogenase (G6PD) activity was increased threefold in hypoxic CD133(+) cells. The increased G6PD activity was required for CD133(+) cell proliferation, and their growth was arrested by G6PD inhibition or knockdown. G6PD activity upregulated expression of HIF1α, cyclin A, and phospho-histone H3, thereby promoting CD133(+) cell dedifferentiation and self-renewal and altering cell cycle regulation. When CD133(+) cells were cocultured across a porous membrane from pulmonary artery smooth muscle cells (PASMCs), G6PD-dependent H2O2 production and release by PASMCs recruited CD133(+) cells to the membrane, where they attached and expressed smooth muscle markers (α-actin and SM22α). Inhibition of G6PD reduced smooth muscle marker expression in CD133(+) cells under normoxia but not hypoxia. In vivo, CD133(+) cells colocalized with G6PD(+) cells in the perivascular region of lungs from rats with hypoxia-induced pulmonary hypertension. Finally, inhibition of G6PD by dehydroepiandrosterone in pulmonary arterial hypertensive rats nearly abolished CD133(+) cell accumulation around pulmonary arteries and the formation of occlusive lesions. These observations suggest G6PD plays a key role in increasing hypoxia-induced CD133(+) cell survival in hypertensive lungs that differentiate to smooth muscle cells and contribute to pulmonary arterial remodeling during development of pulmonary hypertension.
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Affiliation(s)
- Sukrutha Chettimada
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
| | - Sachindra Raj Joshi
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
| | - Abdallah Alzoubi
- Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Sarah A Gebb
- Department of Cell Biology and Neuroscience, University of South Alabama, Mobile, Alabama; and
| | - Ivan F McMurtry
- Department of Pharmacology, College of Medicine, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
| | - Rakhee Gupte
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama;
| | - Sachin A Gupte
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama; Center for Lung Biology, University of South Alabama, Mobile, Alabama
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263
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Imaging liver and brain glycogen metabolism at the nanometer scale. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2014; 11:239-45. [PMID: 25262580 DOI: 10.1016/j.nano.2014.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 08/04/2014] [Accepted: 09/12/2014] [Indexed: 11/20/2022]
Abstract
In mammals, glycogen synthesis and degradation are dynamic processes regulating blood and cerebral glucose-levels within a well-defined physiological range. Despite the essential role of glycogen in hepatic and cerebral metabolism, its spatiotemporal distribution at the molecular and cellular level is unclear. By correlating electron microscopy and ultra-high resolution ion microprobe (NanoSIMS) imaging of tissue from fasted mice injected with (13)C-labeled glucose, we demonstrate that liver glycogenesis initiates in the hepatocyte perinuclear region before spreading toward the cell membrane. In the mouse brain, we observe that (13)C is inhomogeneously incorporated into astrocytic glycogen at a rate ~25 times slower than in the liver, in agreement with prior bulk studies. This experiment, using temporally resolved, nanometer-scale imaging of glycogen synthesis and degradation, provides greater insight into glucose metabolism in mammalian organs and shows how this technique can be used to explore biochemical pathways in healthy and diseased states.
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264
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Bensaad K, Favaro E, Lewis CA, Peck B, Lord S, Collins JM, Pinnick KE, Wigfield S, Buffa FM, Li JL, Zhang Q, Wakelam MJO, Karpe F, Schulze A, Harris AL. Fatty acid uptake and lipid storage induced by HIF-1α contribute to cell growth and survival after hypoxia-reoxygenation. Cell Rep 2014; 9:349-365. [PMID: 25263561 DOI: 10.1016/j.celrep.2014.08.056] [Citation(s) in RCA: 443] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 07/16/2014] [Accepted: 08/22/2014] [Indexed: 01/22/2023] Open
Abstract
An in vivo model of antiangiogenic therapy allowed us to identify genes upregulated by bevacizumab treatment, including Fatty Acid Binding Protein 3 (FABP3) and FABP7, both of which are involved in fatty acid uptake. In vitro, both were induced by hypoxia in a hypoxia-inducible factor-1α (HIF-1α)-dependent manner. There was a significant lipid droplet (LD) accumulation in hypoxia that was time and O2 concentration dependent. Knockdown of endogenous expression of FABP3, FABP7, or Adipophilin (an essential LD structural component) significantly impaired LD formation under hypoxia. We showed that LD accumulation is due to FABP3/7-dependent fatty acid uptake while de novo fatty acid synthesis is repressed in hypoxia. We also showed that ATP production occurs via β-oxidation or glycogen degradation in a cell-type-dependent manner in hypoxia-reoxygenation. Finally, inhibition of lipid storage reduced protection against reactive oxygen species toxicity, decreased the survival of cells subjected to hypoxia-reoxygenation in vitro, and strongly impaired tumorigenesis in vivo.
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Affiliation(s)
- Karim Bensaad
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK.
| | - Elena Favaro
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Caroline A Lewis
- Gene Expression Analysis Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Barrie Peck
- Gene Expression Analysis Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Simon Lord
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Jennifer M Collins
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Katherine E Pinnick
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Simon Wigfield
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Francesca M Buffa
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Ji-Liang Li
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Qifeng Zhang
- The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | | | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology & Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK; NIHR Oxford Biomedical Research Centre, OUH Trust, Churchill Hospital, Oxford OX3 7LF, UK
| | - Almut Schulze
- Gene Expression Analysis Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK; Department of Biochemistry and Molecular Biology, Theodor Boveri Institute, Biocenter, Am Hubland, 97074 Würzburg, Germany
| | - Adrian L Harris
- CRUK Hypoxia and Angiogenesis Group, The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
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265
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Verdegem D, Moens S, Stapor P, Carmeliet P. Endothelial cell metabolism: parallels and divergences with cancer cell metabolism. Cancer Metab 2014; 2:19. [PMID: 25250177 PMCID: PMC4171726 DOI: 10.1186/2049-3002-2-19] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/14/2014] [Indexed: 02/08/2023] Open
Abstract
The stromal vasculature in tumors is a vital conduit of nutrients and oxygen for cancer cells. To date, the vast majority of studies have focused on unraveling the genetic basis of vessel sprouting (also termed angiogenesis). In contrast to the widely studied changes in cancer cell metabolism, insight in the metabolic regulation of angiogenesis is only just emerging. These studies show that metabolic pathways in endothelial cells (ECs) importantly regulate angiogenesis in conjunction with genetic signals. In this review, we will highlight these emerging insights in EC metabolism and discuss them in perspective of cancer cell metabolism. While it is generally assumed that cancer cells have unique metabolic adaptations, not shared by healthy non-transformed cells, we will discuss parallels and highlight differences between endothelial and cancer cell metabolism and consider possible novel therapeutic opportunities arising from targeting both cancer and endothelial cells.
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Affiliation(s)
- Dries Verdegem
- Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, Department of Oncology, University of Leuven, Leuven 3000, Belgium ; Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, VIB, K.U.Leuven, Campus Gasthuisberg, Herestraat 49, box 912, Leuven 3000, Belgium
| | - Stijn Moens
- Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, Department of Oncology, University of Leuven, Leuven 3000, Belgium ; Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, VIB, K.U.Leuven, Campus Gasthuisberg, Herestraat 49, box 912, Leuven 3000, Belgium
| | - Peter Stapor
- Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, Department of Oncology, University of Leuven, Leuven 3000, Belgium ; Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, VIB, K.U.Leuven, Campus Gasthuisberg, Herestraat 49, box 912, Leuven 3000, Belgium
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, Department of Oncology, University of Leuven, Leuven 3000, Belgium ; Laboratory of Angiogenesis and Neurovascular link, Vesalius Research Center, VIB, K.U.Leuven, Campus Gasthuisberg, Herestraat 49, box 912, Leuven 3000, Belgium
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266
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Rombouts C, Aerts A, Quintens R, Baselet B, El-Saghire H, Harms-Ringdahl M, Haghdoost S, Janssen A, Michaux A, Yentrapalli R, Benotmane MA, Van Oostveldt P, Baatout S. Transcriptomic profiling suggests a role for IGFBP5 in premature senescence of endothelial cells after chronic low dose rate irradiation. Int J Radiat Biol 2014; 90:560-74. [PMID: 24646080 DOI: 10.3109/09553002.2014.905724] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE Ionizing radiation has been recognized to increase the risk of cardiovascular diseases (CVD). However, there is no consensus concerning the dose-risk relationship for low radiation doses and a mechanistic understanding of low dose effects is needed. MATERIAL AND METHODS Previously, human umbilical vein endothelial cells (HUVEC) were exposed to chronic low dose rate radiation (1.4 and 4.1 mGy/h) during one, three and six weeks which resulted in premature senescence in cells exposed to 4.1 mGy/h. To gain more insight into the underlying signaling pathways, we analyzed gene expression changes in these cells using microarray technology. The obtained data were analyzed in a dual approach, combining single gene expression analysis and Gene Set Enrichment Analysis. RESULTS An early stress response was observed after one week of exposure to 4.1 mGy/h which was replaced by a more inflammation-related expression profile after three weeks and onwards. This early stress response may trigger the radiation-induced premature senescence previously observed in HUVEC irradiated with 4.1 mGy/h. A dedicated analysis pointed to the involvement of insulin-like growth factor binding protein 5 (IGFBP5) signaling in radiation-induced premature senescence. CONCLUSION Our findings motivate further research on the shape of the dose-response and the dose rate effect for radiation-induced vascular senescence.
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Affiliation(s)
- Charlotte Rombouts
- Radiobiology Unit, Belgian Nuclear Research Centre, SCK•CEN , Mol , Belgium
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267
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Czifrák K, Páhi A, Deák S, Kiss-Szikszai A, Kövér KE, Docsa T, Gergely P, Alexacou KM, Papakonstantinou M, Leonidas DD, Zographos SE, Chrysina ED, Somsák L. Glucopyranosylidene-spiro-iminothiazolidinone, a new bicyclic ring system: Synthesis, derivatization, and evaluation for inhibition of glycogen phosphorylase by enzyme kinetic and crystallographic methods. Bioorg Med Chem 2014; 22:4028-41. [DOI: 10.1016/j.bmc.2014.05.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/25/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
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268
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Rajagopalan V, Vaidyanathan M, Janardhanam VA, Bradner JE. Pre-clinical analysis of changes in intra-cellular biochemistry of glioblastoma multiforme (GBM) cells due to c-Myc silencing. Cell Mol Neurobiol 2014; 34:1059-69. [PMID: 25056450 DOI: 10.1007/s10571-014-0083-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/06/2014] [Indexed: 01/24/2023]
Abstract
Glioblastoma Multiforme (GBM) is an aggressive form of brain Tumor that has few cures. In this study, we analyze the anti-proliferative effects of a new molecule JQ1 against GBMs induced in Wistar Rats. JQ1 is essentially a Myc inhibitor. c-Myc is also known for altering the biochemistry of a tumor cell. Therefore, the study is intended to analyze certain other oncogenes associated with c-Myc and also the change in cellular biochemistry upon c-Myc inhibition. The quantitative analysis of gene expression gave a co-expressive pattern for all the three genes involved namely; c-Myc, Bcl-2, and Akt. The cellular biochemistry analysis by transmission electron microscopy revealed high glycogen and lipid aggregation in Myc inhibited cells and excessive autophagy. The study demonstrates the role of c-Myc as a central metabolic regulator and Bcl-2 and Akt assisting in extending c-Myc half-life as well as in regulation of autophagy, so as to regulate cell survival on the whole. The study also demonstrates that transient treatment by JQ1 leads to aggressive development of tumor and therefore, accelerating death, emphasizing the importance of dosage fixation, and duration for clinical use in future.
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Affiliation(s)
- Vishal Rajagopalan
- Department of Biochemistry, University of Madras, Guindy Campus, Chennai, 600025, India,
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269
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Jones DR, Keune WJ, Anderson KE, Stephens LR, Hawkins PT, Divecha N. The hexosamine biosynthesis pathway and O-GlcNAcylation maintain insulin-stimulated PI3K-PKB phosphorylation and tumour cell growth after short-term glucose deprivation. FEBS J 2014; 281:3591-608. [PMID: 24938479 DOI: 10.1111/febs.12879] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 05/09/2014] [Accepted: 06/12/2014] [Indexed: 12/16/2022]
Abstract
Glucose provides an essential nutrient source that supports glycolysis and the hexosamine biosynthesis pathway (HBP) to maintain tumour cell growth and survival. Here we investigated if short-term glucose deprivation specifically modulates the phosphatidylinositol 3-kinase/protein kinase B (PI3K/PKB) cell survival pathway. Insulin-stimulated PKB activation was strongly abrogated in the absence of extracellular glucose as a consequence of the loss of insulin-stimulated PI3K activation and short-term glucose deprivation inhibited subsequent tumour cell growth. Loss of insulin-stimulated PKB signalling and cell growth was rescued by extracellular glucosamine and increased flux through the HBP. Disruption of O-GlcNAc transferase activity, a terminal step in the HBP, implicated O-GlcNAcylation in PKB signalling and cell growth. Glycogenolysis is known to support cell survival during glucose deprivation, and in A549 lung cancer cells its inhibition attenuates PKB activation which is rescued by increased flux through the HBP. Our studies show that rerouting of glycolytic metabolites to the HBP under glucose-restricted conditions maintains PI3K/PKB signalling enabling cell survival and proliferation.
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Affiliation(s)
- David R Jones
- Inositide Laboratory, Cancer Research UK Manchester Institute, University of Manchester, UK
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270
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Abbadi S, Rodarte JJ, Abutaleb A, Lavell E, Smith CL, Ruff W, Schiller J, Olivi A, Levchenko A, Guerrero-Cazares H, Quinones-Hinojosa A. Glucose-6-phosphatase is a key metabolic regulator of glioblastoma invasion. Mol Cancer Res 2014; 12:1547-59. [PMID: 25001192 DOI: 10.1158/1541-7786.mcr-14-0106-t] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Glioblastoma (GBM) remains the most aggressive primary brain cancer in adults. Similar to other cancers, GBM cells undergo metabolic reprogramming to promote proliferation and survival. Glycolytic inhibition is widely used to target such reprogramming. However, the stability of glycolytic inhibition in GBM remains unclear especially in a hypoxic tumor microenvironment. In this study, it was determined that glucose-6-phosphatase (G6PC/G6Pase) expression is elevated in GBM when compared with normal brain. Human-derived brain tumor-initiating cells (BTIC) use this enzyme to counteract glycolytic inhibition induced by 2-deoxy-d-glucose (2DG) and sustain malignant progression. Downregulation of G6PC renders the majority of these cells unable to survive glycolytic inhibition, and promotes glycogen accumulation through the activation of glycogen synthase (GYS1) and inhibition of glycogen phosphorylase (PYGL). Moreover, BTICs that survive G6PC knockdown are less aggressive (reduced migration, invasion, proliferation, and increased astrocytic differentiation). Collectively, these findings establish G6PC as a key enzyme with promalignant functional consequences that has not been previously reported in GBM and identify it as a potential therapeutic target. IMPLICATIONS This study is the first to demonstrate a functional relationship between the critical gluconeogenic and glycogenolytic enzyme G6PC with the metabolic adaptations during GBM invasion.
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Affiliation(s)
- Sara Abbadi
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Julio J Rodarte
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ameer Abutaleb
- University of Maryland, School of Medicine, Baltimore, Maryland
| | - Emily Lavell
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Chris L Smith
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland. Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - William Ruff
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Alessandro Olivi
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Andre Levchenko
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hugo Guerrero-Cazares
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
| | - Alfredo Quinones-Hinojosa
- Department of Neurosurgery and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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271
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Bae E, Kim HE, Koh E, Kim KS. Phosphoglucomutase1 is necessary for sustained cell growth under repetitive glucose depletion. FEBS Lett 2014; 588:3074-80. [DOI: 10.1016/j.febslet.2014.06.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 06/09/2014] [Accepted: 06/10/2014] [Indexed: 01/01/2023]
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272
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New synthesis of 3-(β-D-glucopyranosyl)-5-substituted-1,2,4-triazoles, nanomolar inhibitors of glycogen phosphorylase. Eur J Med Chem 2014; 76:567-79. [DOI: 10.1016/j.ejmech.2014.02.041] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 02/11/2014] [Accepted: 02/14/2014] [Indexed: 11/18/2022]
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273
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Witney TH, Carroll L, Alam IS, Chandrashekran A, Nguyen QD, Sala R, Harris R, DeBerardinis RJ, Agarwal R, Aboagye EO. A novel radiotracer to image glycogen metabolism in tumors by positron emission tomography. Cancer Res 2014; 74:1319-28. [PMID: 24590807 PMCID: PMC3966281 DOI: 10.1158/0008-5472.can-13-2768] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The high rate of glucose uptake to fuel the bioenergetic and anabolic demands of proliferating cancer cells is well recognized and is exploited with (18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography ((18)F-FDG-PET) to image tumors clinically. In contrast, enhanced glucose storage as glycogen (glycogenesis) in cancer is less well understood and the availability of a noninvasive method to image glycogen in vivo could provide important biologic insights. Here, we demonstrate that (18)F-N-(methyl-(2-fluoroethyl)-1H-[1,2,3]triazole-4-yl)glucosamine ((18)F-NFTG) annotates glycogenesis in cancer cells and tumors in vivo, measured by PET. Specificity of glycogen labeling was demonstrated by isolating (18)F-NFTG-associated glycogen and with stable knockdown of glycogen synthase 1, which inhibited (18)F-NFTG uptake, whereas oncogene (Rab25) activation-associated glycogen synthesis led to increased uptake. We further show that the rate of glycogenesis is cell-cycle regulated, enhanced during the nonproliferative state of cancer cells. We demonstrate that glycogen levels, (18)F-NFTG, but not (18)F-FDG uptake, increase proportionally with cell density and G1-G0 arrest, with potential application in the assessment of activation of oncogenic pathways related to glycogenesis and the detection of posttreatment tumor quiescence.
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Affiliation(s)
- Timothy H Witney
- Authors' Affiliations: Comprehensive Cancer Imaging Centre; and Ovarian Cancer Action Research Centre, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Hammersmith Hospital, London, United Kingdom; and Children's Medical Center Research Institute, University of Texas, Southwestern Medical Center at Dallas, Dallas, Texas
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274
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Masson N, Ratcliffe PJ. Hypoxia signaling pathways in cancer metabolism: the importance of co-selecting interconnected physiological pathways. Cancer Metab 2014; 2:3. [PMID: 24491179 PMCID: PMC3938304 DOI: 10.1186/2049-3002-2-3] [Citation(s) in RCA: 217] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 01/22/2014] [Indexed: 12/31/2022] Open
Abstract
Both tumor hypoxia and dysregulated metabolism are classical features of cancer. Recent analyses have revealed complex interconnections between oncogenic activation, hypoxia signaling systems and metabolic pathways that are dysregulated in cancer. These studies have demonstrated that rather than responding simply to error signals arising from energy depletion or tumor hypoxia, metabolic and hypoxia signaling pathways are also directly connected to oncogenic signaling mechanisms at many points. This review will summarize current understanding of the role of hypoxia inducible factor (HIF) in these networks. It will also discuss the role of these interconnected pathways in generating the cancer phenotype; in particular, the implications of switching massive pathways that are physiologically 'hard-wired’ to oncogenic mechanisms driving cancer.
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Affiliation(s)
| | - Peter J Ratcliffe
- The Hypoxia Biology Laboratory, The Henry Wellcome Building for Molecular Physiology, The University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.
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275
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Philips KB, Kurtoglu M, Leung HJ, Liu H, Gao N, Lehrman MA, Murray TG, Lampidis TJ. Increased sensitivity to glucose starvation correlates with downregulation of glycogen phosphorylase isoform PYGB in tumor cell lines resistant to 2-deoxy-D-glucose. Cancer Chemother Pharmacol 2014; 73:349-61. [PMID: 24292700 PMCID: PMC4570497 DOI: 10.1007/s00280-013-2358-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 11/11/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND As tumors evolve, they upregulate glucose metabolism while also encountering intermittent periods of glucose deprivation. Here, we investigate mechanisms by which pancreatic cancer cells respond to therapeutic (2-deoxy-D-glucose, 2-DG) and physiologic (glucose starvation, GS) forms of glucose restriction. METHODS From a tumor cell line (1420) that is unusually sensitive to 2-DG under normoxia, low (14DG2)- and high (14DG5)-dose resistant cell lines were selected and used to probe the metabolic pathways involved with their response to different forms of glucose deprivation. RESULTS Muted induction of the unfolded protein response was found to correlate with resistance to 2-DG. Additionally, 14DG2 displayed reduced 2-DG uptake, while 14DG5 was cross-resistant to tunicamycin, suggesting it has enhanced ability to manage glycosylation defects. Conversely, 2-DG-resistant cell lines were more sensitive than their parental cell line to GS, which coincided with lowered levels of glycogen phosphorylase (PYGB) and reduced breakdown of glycogen to glucose in the 2-DG-resistant cell lines. Moreover, by inhibiting PYGB in the parental cell line, sensitivity to GS was increased. CONCLUSIONS Overall, the data demonstrate that the manner in which glucose is restricted in tumor cells, i.e., therapeutic or physiologic, leads to differential biological responses involving distinct glucose metabolic pathways. Moreover, in evolving tumors where glucose restriction occurs, the identification of PYGB as a metabolic target may have clinical application.
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Affiliation(s)
- Katherine B. Philips
- Sheila and David Fuente Graduate Program in Cancer Biology, University of Miami Miller School of Medicine, 1550 NW 10th Avenue, Fox Building #406, Miami, FL 33136, USA,
| | - Metin Kurtoglu
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, PAP Building, Room 115, 1550 NW 10th Ave, Miami, FL 33136, USA,
| | - Howard J. Leung
- Sheila and David Fuente Graduate Program in Cancer Biology, University of Miami Miller School of Medicine, 1550 NW 10th Avenue, Fox Building #406, Miami, FL 33136, USA,
| | - Huaping Liu
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, PAP Building, Room 115, 1550 NW 10th Ave, Miami, FL 33136, USA,
| | - Ningguo Gao
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX 75390-9041, USA,
| | - Mark A. Lehrman
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX 75390-9041, USA,
| | - Timothy G. Murray
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, 900 NW 17th St., Miami, FL 33136, USA,
| | - Theodore J. Lampidis
- Department of Cell Biology (R-124), University of Miami Miller School of Medicine, 1600 NW 10th Avenue, Rosenstiel Medical Sciences Building #4026/4027, P.O. Box 016960, Miami, FL 33101, USA,
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, 1475 NW 12th Avenue, P.O. Box 016960, Miami, FL 33101, USA
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276
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Eelen G, Cruys B, Welti J, De Bock K, Carmeliet P. Control of vessel sprouting by genetic and metabolic determinants. Trends Endocrinol Metab 2013; 24:589-96. [PMID: 24075830 DOI: 10.1016/j.tem.2013.08.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/26/2013] [Accepted: 08/28/2013] [Indexed: 01/28/2023]
Abstract
Vessel sprouting by endothelial cells (ECs) during angiogenesis relies on a navigating tip cell and on proliferating stalk cells that elongate the shaft. To date, only genetic signals have been shown to regulate vessel sprouting. However, emerging evidence indicates that the angiogenic switch also requires a metabolic switch. Indeed, angiogenic signals not only induce a change in EC metabolism but this metabolic adaptation also co-determines vessel sprouting. The glycolytic activator PFKFB3 regulates stalk cell proliferation and renders ECs more competitive to reach the tip. We discuss the emerging link between angiogenesis and EC metabolism during the various stages of vessel sprouting, focusing only on genetic signals for which an effect on EC metabolism has been documented.
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Affiliation(s)
- Guy Eelen
- Laboratory of Angiogenesis and Neurovascular Link, Vesalius Research Center, Vlaams Instituut voor Biotechnologie (VIB), Department of Oncology, Katholieke Universiteit Leuven (KU Leuven), Herestraat 49, 3000 Leuven, Belgium
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277
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Kennedy KM, Scarbrough PM, Ribeiro A, Richardson R, Yuan H, Sonveaux P, Landon CD, Chi JT, Pizzo S, Schroeder T, Dewhirst MW. Catabolism of exogenous lactate reveals it as a legitimate metabolic substrate in breast cancer. PLoS One 2013; 8:e75154. [PMID: 24069390 PMCID: PMC3771963 DOI: 10.1371/journal.pone.0075154] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 08/09/2013] [Indexed: 01/22/2023] Open
Abstract
Lactate accumulation in tumors has been associated with metastases and poor overall survival in cancer patients. Lactate promotes angiogenesis and metastasis, providing rationale for understanding how it is processed by cells. The concentration of lactate in tumors is a balance between the amount produced, amount carried away by vasculature and if/how it is catabolized by aerobic tumor or stromal cells. We examined lactate metabolism in human normal and breast tumor cell lines and rat breast cancer: 1. at relevant concentrations, 2. under aerobic vs. hypoxic conditions, 3. under conditions of normo vs. hypoglucosis. We also compared the avidity of tumors for lactate vs. glucose and identified key lactate catabolites to reveal how breast cancer cells process it. Lactate was non-toxic at clinically relevant concentrations. It was taken up and catabolized to alanine and glutamate by all cell lines. Kinetic uptake rates of lactate in vivo surpassed that of glucose in R3230Ac mammary carcinomas. The uptake appeared specific to aerobic tumor regions, consistent with the proposed "metabolic symbiont" model; here lactate produced by hypoxic cells is used by aerobic cells. We investigated whether treatment with alpha-cyano-4-hydroxycinnamate (CHC), a MCT1 inhibitor, would kill cells in the presence of high lactate. Both 0.1 mM and 5 mM CHC prevented lactate uptake in R3230Ac cells at lactate concentrations at ≤ 20 mM but not at 40 mM. 0.1 mM CHC was well-tolerated by R3230Ac and MCF7 cells, but 5 mM CHC killed both cell lines ± lactate, indicating off-target effects. This study showed that breast cancer cells tolerate and use lactate at clinically relevant concentrations in vitro (± glucose) and in vivo. We provided additional support for the metabolic symbiont model and discovered that breast cells prevailingly take up and catabolize lactate, providing rationale for future studies on manipulation of lactate catabolism pathways for therapy.
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Affiliation(s)
- Kelly M. Kennedy
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Peter M. Scarbrough
- Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Anthony Ribeiro
- Duke University Shared Resources NMR Facility, Duke University, Durham, North Carolina, United States of America
| | - Rachel Richardson
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Hong Yuan
- Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Pierre Sonveaux
- Pole of Pharmacology, Institut de Recherches Expérimentales et Cliniques (IREC), Université catholique de Louvain (UCL), Brussels, Belgium
| | - Chelsea D. Landon
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Jen-Tsan Chi
- Institute of Genome Sciences and Policy, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Salvatore Pizzo
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Thies Schroeder
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Mark W. Dewhirst
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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278
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Mowla SN, Perkins ND, Jat PS. Friend or foe: emerging role of nuclear factor kappa-light-chain-enhancer of activated B cells in cell senescence. Onco Targets Ther 2013; 6:1221-9. [PMID: 24043947 PMCID: PMC3772761 DOI: 10.2147/ott.s36160] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) proteins are a family of ubiquitously expressed transcription factors that regulate the response to cellular stress. They mediate innate and adaptive immunity through the initiation of an inflammatory response to pro-inflammatory signals. The role of persistent inflammation in aiding tumor development has led to the NF-κB family of transcription factors being strongly implicated in promoting cancer. However, recent studies have now revealed that NF-κB can also function as a tumor suppressor through the induction of cellular senescence. Cellular senescence is a stable cell cycle arrest that normal cells undergo in response to a variety of intrinsic and extrinsic stimuli including: progressive telomere shortening, changes in telomeric structure, or other forms of genotoxic stress. Senescence can compromise tissue repair and regeneration, contributing to tissue and organismal aging via the accumulation of senescent cells, depletion of stem/progenitor cells and secretion of an array of inflammatory cytokines, chemokines, and matrix metalloproteinases. Senescence can also lead to the removal of potentially cancerous cells, thereby acting as a potent tumor suppressor mechanism. Herein, we review the evidence indicating a role for NF-κB in tumor suppression via cellular senescence and suggest that depending upon the subunit expressed, the biological context, and the type and intensity of the signal, NF-κB can indeed promote senescence growth arrest.
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Affiliation(s)
- Sophia N Mowla
- Department of Neurodegenerative Disease and MRC Prion Unit, UCL institute of Neurology, Queen Square, London, UK
| | - Neil D Perkins
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Parmjit S Jat
- Department of Neurodegenerative Disease and MRC Prion Unit, UCL institute of Neurology, Queen Square, London, UK
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279
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Semenza GL. HIF-1 mediates metabolic responses to intratumoral hypoxia and oncogenic mutations. J Clin Invest 2013; 123:3664-71. [PMID: 23999440 DOI: 10.1172/jci67230] [Citation(s) in RCA: 936] [Impact Index Per Article: 85.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Hypoxia occurs frequently in human cancers and induces adaptive changes in cell metabolism that include a switch from oxidative phosphorylation to glycolysis, increased glycogen synthesis, and a switch from glucose to glutamine as the major substrate for fatty acid synthesis. This broad metabolic reprogramming is coordinated at the transcriptional level by HIF-1, which functions as a master regulator to balance oxygen supply and demand. HIF-1 is also activated in cancer cells by tumor suppressor (e.g., VHL) loss of function and oncogene gain of function (leading to PI3K/AKT/mTOR activity) and mediates metabolic alterations that drive cancer progression and resistance to therapy. Inhibitors of HIF-1 or metabolic enzymes may impair the metabolic flexibility of cancer cells and make them more sensitive to anticancer drugs.
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Affiliation(s)
- Gregg L Semenza
- Vascular Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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280
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Nagy L, Docsa T, Szántó M, Brunyánszki A, Hegedűs C, Márton J, Kónya B, Virág L, Somsák L, Gergely P, Bai P. Glycogen phosphorylase inhibitor N-(3,5-dimethyl-Benzoyl)-N'-(β-D-glucopyranosyl)urea improves glucose tolerance under normoglycemic and diabetic conditions and rearranges hepatic metabolism. PLoS One 2013; 8:e69420. [PMID: 23936011 PMCID: PMC3723905 DOI: 10.1371/journal.pone.0069420] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 06/10/2013] [Indexed: 12/22/2022] Open
Abstract
Glycogen phosphorylase (GP) catalyzes the breakdown of glycogen and largely contributes to hepatic glucose production making GP inhibition an attractive target to modulate glucose levels in diabetes. Hereby we present the metabolic effects of a novel, potent, glucose-based GP inhibitor (KB228) tested in vitro and in vivo under normoglycemic and diabetic conditions. KB228 administration enhanced glucose sensitivity in chow-fed and obese, diabetic mice that was a result of higher hepatic glucose uptake. Besides improved glucose sensitivity, we have observed further unexpected metabolic rearrangements. KB228 administration increased oxygen consumption that was probably due to the overexpression of uncoupling protein-2 (UCP2) that was observed in animal and cellular models. Furthermore, KB228 treatment induced mammalian target of rapamycin complex 2 (mTORC2) in mice. Our data demonstrate that glucose based GP inhibitors are capable of reducing glucose levels in mice under normo and hyperglycemic conditions. Moreover, these GP inhibitors induce accommodation in addition to GP inhibition - such as enhanced mitochondrial oxidation and mTORC2 signaling – to cope with the glucose influx and increased glycogen deposition in the cells, however the molecular mechanism of accommodation is unexplored.
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Affiliation(s)
- Lilla Nagy
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
| | - Tibor Docsa
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
| | - Magdolna Szántó
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
- Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, Debrecen, Hungary
| | - Attila Brunyánszki
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
| | - Csaba Hegedűs
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
| | - Judit Márton
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
| | - Bálint Kónya
- Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
| | - László Virág
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
- Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, Debrecen, Hungary
| | - László Somsák
- Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
| | - Pál Gergely
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
- Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, Debrecen, Hungary
| | - Péter Bai
- Department of Medical Chemistry, University of Debrecen Medical and Health Science Center, Debrecen, Hungary
- Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, Debrecen, Hungary
- * E-mail:
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281
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Zhou X, Shi T, Li B, Zhang Y, Shen X, Li H, Hong G, Liu C, Guo Z. Genes dysregulated to different extent or oppositely in estrogen receptor-positive and estrogen receptor-negative breast cancers. PLoS One 2013; 8:e70017. [PMID: 23875016 PMCID: PMC3715479 DOI: 10.1371/journal.pone.0070017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 06/14/2013] [Indexed: 12/22/2022] Open
Abstract
Background Directly comparing gene expression profiles of estrogen receptor-positive (ER+) and estrogen receptor-negative (ER−) breast cancers cannot determine whether differentially expressed genes between these two subtypes result from dysregulated expression in ER+ cancer or ER− cancer versus normal controls, and thus would miss critical information for elucidating the transcriptomic difference between the two subtypes. Principal Findings Using microarray datasets from TCGA, we classified the genes dysregulated in both ER+ and ER− cancers versus normal controls into two classes: (i) genes dysregulated in the same direction but to a different extent, and (ii) genes dysregulated to opposite directions, and then validated the two classes in RNA-sequencing datasets of independent cohorts. We showed that the genes dysregulated to a larger extent in ER+ cancers than in ER− cancers enriched in glycerophospholipid and polysaccharide metabolic processes, while the genes dysregulated to a larger extent in ER− cancers than in ER+ cancers enriched in cell proliferation. Phosphorylase kinase and enzymes of glycosylphosphatidylinositol (GPI) anchor biosynthesis were upregulated to a larger extent in ER+ cancers than in ER− cancers, whereas glycogen synthase and phospholipase A2 were downregulated to a larger extent in ER+ cancers than in ER− cancers. We also found that the genes oppositely dysregulated in the two subtypes significantly enriched with known cancer genes and tended to closely collaborate with the cancer genes. Furthermore, we showed the possibility that these oppositely dysregulated genes could contribute to carcinogenesis of ER+ and ER− cancers through rewiring different subpathways. Conclusions GPI-anchor biosynthesis and glycogenolysis were elevated and hydrolysis of phospholipids was depleted to a larger extent in ER+ cancers than in ER− cancers. Our findings indicate that the genes oppositely dysregulated in the two subtypes are potential cancer genes which could contribute to carcinogenesis of both ER+ and ER− cancers through rewiring different subpathways.
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Affiliation(s)
- Xianxiao Zhou
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Tongwei Shi
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Bailiang Li
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, China
- Genomics Research Center, Harbin Medical University, Harbin, China
| | - Yuannv Zhang
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, China
| | - Xiaopei Shen
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Hongdong Li
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Guini Hong
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Chunyang Liu
- Department of Bioinformatics, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
| | - Zheng Guo
- Bioinformatics Centre and Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, China
- Department of Bioinformatics, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
- * E-mail:
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282
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Gaboriaud-Kolar N, Skaltsounis AL. Glycogen phosphorylase inhibitors: a patent review (2008 - 2012). Expert Opin Ther Pat 2013; 23:1017-32. [PMID: 23627914 DOI: 10.1517/13543776.2013.794790] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Glycogen phosphorylase (GP) is the enzyme responsible for the synthesis of glucose-1-phosphate, the source of energy for muscles and the rest of the body. The binding of different ligands in catalytic or allosteric sites assures activation and deactivation of the enzyme. A description of the regulation mechanism and the implications in glycogen metabolism are given. AREAS COVERED Deregulation of GP has been observed in diseases such as diabetes mellitus or cancers. Therefore, it appears as an attractive therapeutic target for the treatment of such pathologies. Numbers of inhibitors have been published in academic literature or patented in the last two decades. This review presents the main patent claims published between 2008 and 2012. EXPERT OPINION Good inhibitors with interesting IC50 and in vivo results are presented. However, such therapeutic strategy raises questions and some answers are proposed to bring new insights in the field.
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283
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Guillaumond F, Vasseur S. The metabolic facet of pancreatic cancer: how hypoxia shapes fatal cancer cells. Cell Cycle 2013; 12:1155-6. [PMID: 23549167 PMCID: PMC3674075 DOI: 10.4161/cc.24489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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284
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Favaro E, Harris AL. Targeting glycogen metabolism: a novel strategy to inhibit cancer cell growth? Oncotarget 2013; 4:3-4. [PMID: 23448808 PMCID: PMC3702200 DOI: 10.18632/oncotarget.841] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 01/26/2013] [Indexed: 12/21/2022] Open
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285
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Abstract
Glycogen metabolism operates as an alternative energy source, enabling cell growth under conditions of metabolic stress. Favaro et al. (2012) now demonstrate that in hypoxic cancer cells, depletion of liver glycogen phosphorylase causes glycogen accumulation, leading to oxidative stress, induction of senescence, and impaired tumor growth in vivo.
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Affiliation(s)
- Susana Ros
- Gene Expression Analysis Laboratory, Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
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