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Conversion of Hyperpolarized [1- 13C]Pyruvate in Breast Cancer Cells Depends on Their Malignancy, Metabolic Program and Nutrient Microenvironment. Cancers (Basel) 2022; 14:cancers14071845. [PMID: 35406616 PMCID: PMC8997828 DOI: 10.3390/cancers14071845] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 03/25/2022] [Accepted: 04/01/2022] [Indexed: 12/19/2022] Open
Abstract
Hyperpolarized magnetic resonance spectroscopy (MRS) is a technology for characterizing tumors in vivo based on their metabolic activities. The conversion rates (kpl) of hyperpolarized [1-13C]pyruvate to [1-13C]lactate depend on monocarboxylate transporters (MCT) and lactate dehydrogenase (LDH); these are also indicators of tumor malignancy. An unresolved issue is how glucose and glutamine availability in the tumor microenvironment affects metabolic characteristics of the cancer and how this relates to kpl-values. Two breast cancer cells of different malignancy (MCF-7, MDA-MB-231) were cultured in media containing defined combinations of low glucose (1 mM; 2.5 mM) and glutamine (0.1 mM; 1 mM) and analyzed for pyruvate uptake, intracellular metabolite levels, LDH and pyruvate kinase activities, and 13C6-glucose-derived metabolomics. The results show variability of kpl with the different glucose/glutamine conditions, congruent with glycolytic activity, but not with LDH activity or the Warburg effect; this suggests metabolic compartmentation. Remarkably, kpl-values were almost two-fold higher in MCF-7 than in the more malignant MDA-MB-231 cells, the latter showing a higher flux of 13C-glucose-derived pyruvate to the TCA-cycle metabolites 13C2-citrate and 13C3-malate, i.e., pyruvate decarboxylation and carboxylation, respectively. Thus, MRS with hyperpolarized [1-13C-pyruvate] is sensitive to both the metabolic program and the nutritional state of cancer cells.
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2
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Duraj T, Carrión-Navarro J, Seyfried TN, García-Romero N, Ayuso-Sacido A. Metabolic therapy and bioenergetic analysis: The missing piece of the puzzle. Mol Metab 2021; 54:101389. [PMID: 34749013 PMCID: PMC8637646 DOI: 10.1016/j.molmet.2021.101389] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Aberrant metabolism is recognized as a hallmark of cancer, a pillar necessary for cellular proliferation. Regarding bioenergetics (ATP generation), most cancers display a preference not only toward aerobic glycolysis ("Warburg effect") and glutaminolysis (mitochondrial substrate level-phosphorylation) but also toward other metabolites such as lactate, pyruvate, and fat-derived sources. These secondary metabolites can assist in proliferation but cannot fully cover ATP demands. SCOPE OF REVIEW The concept of a static metabolic profile is challenged by instances of heterogeneity and flexibility to meet fuel/anaplerotic demands. Although metabolic therapies are a promising tool to improve therapeutic outcomes, either via pharmacological targets or press-pulse interventions, metabolic plasticity is rarely considered. Lack of bioenergetic analysis in vitro and patient-derived models is hindering translational potential. Here, we review the bioenergetics of cancer and propose a simple analysis of major metabolic pathways, encompassing both affordable and advanced techniques. A comprehensive compendium of Seahorse XF bioenergetic measurements is presented for the first time. MAJOR CONCLUSIONS Standardization of principal readouts might help researchers to collect a complete metabolic picture of cancer using the most appropriate methods depending on the sample of interest.
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Affiliation(s)
- Tomás Duraj
- Faculty of Medicine, Institute for Applied Molecular Medicine (IMMA), CEU San Pablo University, 28668, Madrid, Spain.
| | - Josefa Carrión-Navarro
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223, Madrid, Spain; Brain Tumor Laboratory, Fundación Vithas, Grupo Hospitales Vithas, 28043, Madrid, Spain.
| | - Thomas N Seyfried
- Biology Department, Boston College, 140 Commonwealth Ave, Chestnut Hill, MA, 02467, USA.
| | - Noemí García-Romero
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223, Madrid, Spain; Brain Tumor Laboratory, Fundación Vithas, Grupo Hospitales Vithas, 28043, Madrid, Spain.
| | - Angel Ayuso-Sacido
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223, Madrid, Spain; Brain Tumor Laboratory, Fundación Vithas, Grupo Hospitales Vithas, 28043, Madrid, Spain; Faculty of Medicine, Universidad Francisco de Vitoria, 28223, Madrid, Spain.
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3
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Vaupel P, Multhoff G. Revisiting the Warburg effect: historical dogma versus current understanding. J Physiol 2021; 599:1745-1757. [PMID: 33347611 DOI: 10.1113/jp278810] [Citation(s) in RCA: 346] [Impact Index Per Article: 115.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/03/2020] [Indexed: 12/20/2022] Open
Abstract
Contrary to Warburg's original thesis, accelerated aerobic glycolysis is not a primary, permanent and universal consequence of dysfunctional or impaired mitochondria compensating for poor ATP yield per mole of glucose. Instead, in most tumours the Warburg effect is an essential part of a 'selfish' metabolic reprogramming, which results from the interplay between (normoxic/hypoxic) hypoxia-inducible factor-1 (HIF-1) overexpression, oncogene activation (cMyc, Ras), loss of function of tumour suppressors (mutant p53, mutant phosphatase and tensin homologue (PTEN), microRNAs and sirtuins with suppressor functions), activated (PI3K-Akt-mTORC1, Ras-Raf-MEK-ERK-cMyc, Jak-Stat3) or deactivated (LKB1-AMPK) signalling pathways, components of the tumour microenvironment, and HIF-1 cooperation with epigenetic mechanisms. Molecular and functional processes of the Warburg effect include: (a) considerable acceleration of glycolytic fluxes; (b) adequate ATP generation per unit time to maintain energy homeostasis and electrochemical gradients; (c) backup and diversion of glycolytic intermediates facilitating the biosynthesis of nucleotides, non-essential amino acids, lipids and hexosamines; (d) inhibition of pyruvate entry into mitochondria; (e) excessive formation and accumulation of lactate, which stimulates tumour growth and suppression of anti-tumour immunity - in addition, lactate can serve as an energy source for normoxic cancer cells and drives malignant progression and resistances to conventional therapies; (f) cytosolic lactate being mainly exported through upregulated lactate-proton symporters (MCT4), working together with other H+ transporters, and carbonic anhydrases (CAII, CAIX), which hydrate CO2 from oxidative metabolism to form H+ and bicarbonate; (g) these proton export mechanisms, in concert with poor vascular drainage, being responsible for extracellular acidification, driving malignant progression and resistance to conventional therapies; (h) maintenance of the cellular redox homeostasis and low reactive oxygen species (ROS) formation; and (i) HIF-1 overexpression, mutant p53 and mutant PTEN, which inhibit mitochondrial biogenesis and functions, negatively impacting cellular respiration rate. The glycolytic switch is an early event in oncogenesis and primarily supports cell survival. All in all, the Warburg effect, i.e. aerobic glycolysis in the presence of oxygen and - in principle - functioning mitochondria, constitutes a major driver of the cancer progression machinery, resistance to conventional therapies, and poor patient outcome. However, as evidenced during the last two decades, in a minority of tumours primary mitochondrial defects can play a key role promoting the Warburg effect and tumour progression due to mutations in some Krebs cycle enzymes and mitochondrial ROS overproduction.
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Affiliation(s)
- Peter Vaupel
- Department of Radiation Oncology, Tumour Pathophysiology Group, University Medical Centre, University of Mainz, Germany.,Department of Radiation Oncology, University Medical Centre, University of Freiburg, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Centre (DKFZ), Heidelberg, Germany
| | - Gabriele Multhoff
- Center for Translational Cancer Research, Klinikum rechts der Isar, Technical University Munich, Munich, Germany.,Department of RadioOncology, Klinikum rechts der Isar, Technical University Munich, Munich, Germany
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4
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Esteves M, Monteiro MP, Duarte JA. Role of Regular Physical Exercise in Tumor Vasculature: Favorable Modulator of Tumor Milieu. Int J Sports Med 2020; 42:389-406. [PMID: 33307553 DOI: 10.1055/a-1308-3476] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The tumor vessel network has been investigated as a precursor of an inhospitable tumor microenvironment, including its repercussions in tumor perfusion, oxygenation, interstitial fluid pressure, pH, and immune response. Dysfunctional tumor vasculature leads to the extravasation of blood to the interstitial space, hindering proper perfusion and causing interstitial hypertension. Consequently, the inadequate delivery of oxygen and clearance of by-products of metabolism promote the development of intratumoral hypoxia and acidification, hampering the action of immune cells and resulting in more aggressive tumors. Thus, pharmacological strategies targeting tumor vasculature were developed, but the overall outcome was not satisfactory due to its transient nature and the higher risk of hypoxia and metastasis. Therefore, physical exercise emerged as a potential favorable modulator of tumor vasculature, improving intratumoral vascularization and perfusion. Indeed, it seems that regular exercise practice is associated with lasting tumor vascular maturity, reduced vascular resistance, and increased vascular conductance. Higher vascular conductance reduces intratumoral hypoxia and increases the accessibility of circulating immune cells to the tumor milieu, inhibiting tumor development and improving cancer treatment. The present paper describes the implications of abnormal vasculature on the tumor microenvironment and the underlying mechanisms promoted by regular physical exercise for the re-establishment of more physiological tumor vasculature.
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Affiliation(s)
- Mário Esteves
- Laboratory of Biochemistry and Experimental Morphology, CIAFEL, Porto, Portugal.,Department of Physical Medicine and Rehabilitation, Hospital-Escola, Fernando Pessoa University, Gondomar, Portugal
| | - Mariana P Monteiro
- Unit for Multidisciplinary Research in Biomedicine, Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Jose Alberto Duarte
- CIAFEL - Faculty of Sport, University of Porto, Porto, Portugal.,Instituto Universitário de Ciências da Saúde, Gandra, Portugal
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5
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Otto AM. Metabolic Constants and Plasticity of Cancer Cells in a Limiting Glucose and Glutamine Microenvironment-A Pyruvate Perspective. Front Oncol 2020; 10:596197. [PMID: 33425750 PMCID: PMC7793857 DOI: 10.3389/fonc.2020.596197] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/21/2020] [Indexed: 12/18/2022] Open
Abstract
The metabolism of cancer cells is an issue of dealing with fluctuating and limiting levels of nutrients in a precarious microenvironment to ensure their vitality and propagation. Glucose and glutamine are central metabolites for catabolic and anabolic metabolism, which is in the limelight of numerous diagnostic methods and therapeutic targeting. Understanding tumor metabolism in conditions of nutrient depletion is important for such applications and for interpreting the readouts. To exemplify the metabolic network of tumor cells in a model system, the fate 13C6-glucose was tracked in a breast cancer cell line growing in variable low glucose/low glutamine conditions. 13C-glucose-derived metabolites allowed to deduce the engagement of metabolic pathways, namely glycolysis, the TCA-cycle including glutamine and pyruvate anaplerosis, amino acid synthesis (serine, glycine, aspartate, glutamate), gluconeogenesis, and pyruvate replenishment. While the metabolic program did not change, limiting glucose and glutamine supply reduced cellular metabolite levels and enhanced pyruvate recycling as well as pyruvate carboxylation for entry into the TCA-cycle. Otherwise, the same metabolic pathways, including gluconeogenesis, were similarly engaged with physiologically saturating as with limiting glucose and glutamine. Therefore, the metabolic plasticity in precarious nutritional microenvironment does not require metabolic reprogramming, but is based on dynamic changes in metabolite quantity, reaction rates, and directions of the existing metabolic network.
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Affiliation(s)
- Angela M Otto
- Munich School of BioEngineering, Technical University of Munich, Garching, Germany
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6
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Gkiouli M, Biechl P, Eisenreich W, Otto AM. Diverse Roads Taken by 13C-Glucose-Derived Metabolites in Breast Cancer Cells Exposed to Limiting Glucose and Glutamine Conditions. Cells 2019; 8:cells8101113. [PMID: 31547005 PMCID: PMC6829299 DOI: 10.3390/cells8101113] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/09/2019] [Accepted: 09/18/2019] [Indexed: 12/20/2022] Open
Abstract
In cancers, tumor cells are exposed to fluctuating nutrient microenvironments with limiting supplies of glucose and glutamine. While the metabolic program has been related to the expression of oncogenes, only fractional information is available on how variable precarious nutrient concentrations modulate the cellular levels of metabolites and their metabolic pathways. We thus sought to obtain an overview of the metabolic routes taken by 13C-glucose-derived metabolites in breast cancer MCF-7 cells growing in combinations of limiting glucose and glutamine concentrations. Isotopologue profiles of key metabolites were obtained by gas chromatography/mass spectrometry (GC/MS). They revealed that in limiting and standard saturating medium conditions, the same metabolic routes were engaged, including glycolysis, gluconeogenesis, as well as the TCA cycle with glutamine and pyruvate anaplerosis. However, the cellular levels of 13C-metabolites, for example, serine, alanine, glutamate, malate, and aspartate, were highly sensitive to the available concentrations and the ratios of glucose and glutamine. Notably, intracellular lactate concentrations did not reflect the Warburg effect. Also, isotopologue profiles of 13C-serine as well as 13C-alanine show that the same glucose-derived metabolites are involved in gluconeogenesis and pyruvate replenishment. Thus, anaplerosis and the bidirectional flow of central metabolic pathways ensure metabolic plasticity for adjusting to precarious nutrient conditions.
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Affiliation(s)
- Maria Gkiouli
- Munich School of BioEngineering, Technical University of Munich, 85748 Garching, Germany.
| | - Philipp Biechl
- Munich School of BioEngineering, and Department of Chemistry, Chair of Biochemistry, Technical University of Munich, 85748 Garching, Germany.
| | - Wolfgang Eisenreich
- Department of Chemistry, Chair of Biochemistry, Technical University of Munich, 85748 Garching, Germany.
| | - Angela M Otto
- Munich School of BioEngineering, Technical University of Munich, 85748 Garching, Germany.
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7
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Bröer A, Gauthier-Coles G, Rahimi F, van Geldermalsen M, Dorsch D, Wegener A, Holst J, Bröer S. Ablation of the ASCT2 ( SLC1A5) gene encoding a neutral amino acid transporter reveals transporter plasticity and redundancy in cancer cells. J Biol Chem 2019; 294:4012-4026. [PMID: 30635397 DOI: 10.1074/jbc.ra118.006378] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 01/08/2019] [Indexed: 12/21/2022] Open
Abstract
The neutral amino acid transporter solute carrier family 1 member 5 (SLC1A5 or ASCT2) is overexpressed in many cancers. To identify its roles in tumors, we employed 143B osteosarcoma cells and HCC1806 triple-negative breast cancer cells with or without ASCT2 deletion. ASCT2ko 143B cells grew well in standard culture media, but ASCT2 was required for optimal growth at <0.5 mm glutamine, with tumor spheroid growth and monolayer migration of 143B ASCT2ko cells being strongly impaired at lower glutamine concentrations. However, the ASCT2 deletion did not affect matrix-dependent invasion. ASCT2ko 143B xenografts in nude mice exhibited a slower onset of growth and a higher number of small tumors than ASCT2wt 143B xenografts, but did not differ in average tumor size 25 days after xenotransplantation. ASCT2 deficiency was compensated by increased levels of sodium neutral amino acid transporter 1 (SNAT1 or SLC38A1) and SNAT2 (SLC38A2) in ASCT2ko 143B cells, mediated by a GCN2 EIF2α kinase (GCN2)-dependent pathway, but this compensation was not observed in ASCT2ko HCC1806 cells. Combined SNAT1 silencing and GCN2 inhibition significantly inhibited growth of ASCT2ko HCC1806 cells, but not of ASCT2ko 143B cells. Similarly, pharmacological inhibition of l-type amino acid transporter 1 (LAT1) and GCN2 significantly inhibited growth of ASCT2ko HCC1806 cells, but not of ASCT2ko 143B cells. We conclude that cancer cells with reduced transporter plasticity are more vulnerable to disruption of amino acid homeostasis than cells with a full capacity to up-regulate redundant transporters by an integrated stress response.
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Affiliation(s)
- Angelika Bröer
- From the Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Gregory Gauthier-Coles
- From the Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Farid Rahimi
- From the Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michelle van Geldermalsen
- Origins of Cancer Program, Centenary Institute, University of Sydney, Sydney, New South Wales 2050, Australia.,Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia
| | | | | | - Jeff Holst
- School of Medical Sciences and Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Stefan Bröer
- From the Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia,
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8
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Amend SR, Gatenby RA, Pienta KJ, Brown JS. Cancer Foraging Ecology: Diet Choice, Patch Use, and Habitat Selection of Cancer Cells. CURRENT PATHOBIOLOGY REPORTS 2018. [DOI: 10.1007/s40139-018-0185-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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9
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Böhme I, Bosserhoff AK. Acidic tumor microenvironment in human melanoma. Pigment Cell Melanoma Res 2016; 29:508-23. [PMID: 27233233 DOI: 10.1111/pcmr.12495] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 05/25/2016] [Indexed: 12/18/2022]
Abstract
One characteristic of solid tumors such as malignant melanoma is the acidification of the tumor microenvironment. The deregulation of cancer cell metabolism is considered a main cause of extracellular acidosis. Here, cancer cells utilize aerobic glycolysis instead of oxidative phosphorylation even under normoxic conditions, as originally described by Otto Warburg. These metabolic alterations cause enhanced acid production, especially of lactate and carbon dioxide (CO2 ). The extensive production of acidic metabolites and the enhanced acid export to the extracellular space cause a consistent acidification of the tumor microenvironment, thus promoting the formation of an acid-resistant tumor cell population with increased invasive and metastatic potential. As melanoma is one of the deadliest and most metastatic forms of cancer, understanding the effects of this extracellular acidosis on human melanoma cells with distinct metastatic properties is important. The aim of this review was to summarize recent studies of the acidification of the tumor microenvironment, focusing on the specific effects of the acidic milieu on melanoma cells and to give a short overview of therapeutic approaches.
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Affiliation(s)
- Ines Böhme
- Institute of Biochemistry, Emil-Fischer-Centrum, Friedrich Alexander University Erlangen-Nürnberg, Erlangen-Nürnberg, Germany
| | - Anja Katrin Bosserhoff
- Institute of Biochemistry, Emil-Fischer-Centrum, Friedrich Alexander University Erlangen-Nürnberg, Erlangen-Nürnberg, Germany. .,Comprehensive Cancer Center Erlangen-EMN, University of Erlangen, Erlangen, Germany.
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10
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Mihai AD, Schröder M. Glucose starvation and hypoxia, but not the saturated fatty acid palmitic acid or cholesterol, activate the unfolded protein response in 3T3-F442A and 3T3-L1 adipocytes. Adipocyte 2015; 4:188-202. [PMID: 26257992 DOI: 10.4161/21623945.2014.989728] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 11/08/2014] [Accepted: 11/14/2014] [Indexed: 12/26/2022] Open
Abstract
Obesity is associated with endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR) in adipose tissue. In this study we identify physiological triggers of ER stress and of the UPR in adipocytes in vitro. We show that two markers of adipose tissue remodelling in obesity, glucose starvation and hypoxia, cause ER stress in 3T3-F442A and 3T3-L1 adipocytes. Both conditions induced molecular markers of the IRE1α and PERK branches of the UPR, such as splicing of XBP1 mRNA and CHOP, as well as transcription of the ER stress responsive gene BiP. Hypoxia also induced an increase in phosphorylation of the PERK substrate eIF2α. By contrast, physiological triggers of ER stress in many other cell types, such as the saturated fatty acid palmitic acid, cholesterol, or several inflammatory cytokines including TNF-α, IL-1β, and IL-6, do not cause ER stress in 3T3-F442A and 3T3-L1 adipocytes. Our data suggest that physiological changes associated with remodelling of adipose tissue in obesity, such as hypoxia and glucose starvation, are more likely physiological ER stressors of adipocytes than the lipid overload or hyperinsulinemia associated with obesity.
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11
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Xue H, Ren W, Denkinger M, Schlotzer E, Wischmeyer PE. Nutrition Modulation of Cardiotoxicity and Anticancer Efficacy Related to Doxorubicin Chemotherapy by Glutamine and ω-3 Polyunsaturated Fatty Acids. JPEN J Parenter Enteral Nutr 2015; 40:52-66. [PMID: 25888676 DOI: 10.1177/0148607115581838] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/16/2015] [Indexed: 11/15/2022]
Abstract
BACKGROUND Doxorubicin (DOX) has been one of the most effective antitumor agents against a broad spectrum of malignancies. However, DOX-induced cardiotoxicity forms the major cumulative dose-limiting factor. Glutamine and ω-3 polyunsaturated fatty acids (PUFAs) are putatively cardioprotective during various stresses and/or have potential chemosensitizing effects during cancer chemotherapy. METHODS Antitumor activity and cardiotoxicity of DOX treatment were evaluated simultaneously in a MatBIII mammary adenocarcinoma tumor-bearing rat model treated with DOX (cumulative dose 12 mg/kg). Single or combined treatment of parenteral glutamine (0.35 g/kg) and ω-3 PUFAs (0.19 g/kg eicosapentaenoic acid and 0.18 g/kg docosahexaenoic acid) was administered every other day, starting 6 days before chemotherapy initiation until the end of study (day 50). RESULTS Glutamine alone significantly prevented DOX-related deterioration of cardiac function, reduced serum cardiac troponin I levels, and diminished cardiac lipid peroxidation while not affecting tumor inhibition kinetics. Single ω-3 PUFA treatment significantly enhanced antitumor activity of DOX associated with intensified tumoral oxidative stress and enhanced tumoral DOX concentration while not potentiating cardiac dysfunction or increasing cardiac oxidative stress. Intriguingly, providing glutamine and ω-3 PUFAs together did not consistently confer a greater benefit; conversely, individual benefits on cardiotoxicity and chemosensitization were mostly attenuated or completely lost when combined. CONCLUSIONS Our data demonstrate an interesting differentiality or even dichotomy in the response of tumor and host to single parenteral glutamine and ω-3 PUFA treatments. The intriguing glutamine × ω-3 PUFA interaction observed draws into question the common assumption that there are additive benefits of combinations of nutrients that are beneficial on an individual basis.
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Affiliation(s)
- Hongyu Xue
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado
| | - Wenhua Ren
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado
| | | | | | - Paul E Wischmeyer
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado
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12
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Lankelma J, Kooi B, Krab K, Dorsman JC, Joenje H, Westerhoff HV. A reason for intermittent fasting to suppress the awakening of dormant breast tumors. Biosystems 2014; 127:1-6. [PMID: 25448890 DOI: 10.1016/j.biosystems.2014.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 10/25/2014] [Accepted: 11/01/2014] [Indexed: 12/21/2022]
Abstract
For their growth, dormant tumors, which lack angiogenesis may critically depend on gradients of nutrients and oxygen from the nearest blood vessel. Because for oxygen depletion the distance from the nearest blood vessel to depletion will generally be shorter than for glucose depletion, such tumors will contain anoxic living tumor cells. These cells are dangerous, because they are capable of inducing angiogenesis, which will "wake up" the tumor. Anoxic cells are dependent on anaerobic glucose breakdown for ATP generation. The local extracellular glucose concentration gradient is determined by the blood glucose concentration and by consumption by cells closer to the nearest blood vessel. The blood glucose concentration can be lowered by 20-40% during fasting. We calculated that glucose supply to the potentially hazardous anoxic cells can thereby be reduced significantly, resulting in cell death specifically of the anoxic tumor cells. We hypothesize that intermittent fasting will help to reduce the incidence of tumor relapse via reducing the number of anoxic tumor cells and tumor awakening.
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Affiliation(s)
- Jan Lankelma
- Department of Molecular Cell Physiology, VU University, De Boelelaan 1085, Room G-226a, 1081 HV Amsterdam, The Netherlands.
| | - Bob Kooi
- Department of Theoretical Biology, VU University, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands
| | - Klaas Krab
- Department of Molecular Cell Physiology, VU University, De Boelelaan 1085, Room G-226a, 1081 HV Amsterdam, The Netherlands
| | - Josephine C Dorsman
- Department of Clinical Genetics, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
| | - Hans Joenje
- Department of Clinical Genetics, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
| | - Hans V Westerhoff
- Department of Molecular Cell Physiology, VU University, De Boelelaan 1085, Room G-226a, 1081 HV Amsterdam, The Netherlands; Synthetic Systems Biology, SILS, University of Amsterdam and Manchester Centre for Integrative Systems Biology, The University of Manchester, UK
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13
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Glutamic acid and its derivatives: candidates for rational design of anticancer drugs. Future Med Chem 2013; 5:961-78. [PMID: 23682571 DOI: 10.4155/fmc.13.62] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Throughout the history of human civilizations, cancer has been a major health problem. Its treatment has been interesting but challenging to scientists. Glutamic acid and its derivative glutamine are known to play interesting roles in cancer genesis, hence, it was realized that structurally variant glutamic acid derivatives may be designed and developed and, might be having antagonistic effects on cancer. The present article describes the state-of-art of glutamic acid and its derivatives as anticancer agents. Attempts have been made to explore the effectivity of drug-delivery systems based on glutamic acid for the delivery of anticancer drugs. Moreover, efforts have also been made to discuss the mechanism of action of glutamic acid derivatives as anticancer agents, clinical applications of glutamic acid derivatives, as well as recent developments and future perspectives of glutamic acid drug development have also been discussed.
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14
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Macintyre AN, Rathmell JC. Activated lymphocytes as a metabolic model for carcinogenesis. Cancer Metab 2013; 1:5. [PMID: 24280044 PMCID: PMC3834493 DOI: 10.1186/2049-3002-1-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 10/04/2012] [Indexed: 12/11/2022] Open
Abstract
Metabolic reprogramming is a key event in tumorigenesis to support cell growth, and cancer cells frequently become both highly glycolytic and glutamine dependent. Similarly, T lymphocytes (T cells) modify their metabolism after activation by foreign antigens to shift from an energetically efficient oxidative metabolism to a highly glycolytic and glutamine-dependent metabolic program. This metabolic transition enables T cell growth, proliferation, and differentiation. In both activated T cells and cancer cells metabolic reprogramming is achieved by similar mechanisms and offers similar survival and cell growth advantages. Activated T cells thus present a useful model with which to study the development of tumor metabolism. Here, we review the metabolic similarities and distinctions between activated T cells and cancer cells, and discuss both the common signaling pathways and master metabolic regulators that lead to metabolic rewiring. Ultimately, understanding how and why T cells adopt a cancer cell-like metabolic profile may identify new therapeutic strategies to selectively target tumor metabolism or inflammatory immune responses.
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Affiliation(s)
- Andrew N Macintyre
- Department of Pharmacology and Cancer Biology, Department of Immunology, Sarah W, Stedman Nutrition and Metabolism Center, Duke University, Durham, NC, 27710, USA.
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15
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The growing complexity of HIF-1α’s role in tumorigenesis: DNA repair and beyond. Oncogene 2012; 32:3569-76. [DOI: 10.1038/onc.2012.510] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 09/28/2012] [Accepted: 09/27/2012] [Indexed: 12/13/2022]
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Availability, not respiratory capacity governs oxygen consumption of solid tumors. Int J Biochem Cell Biol 2012; 44:1477-81. [DOI: 10.1016/j.biocel.2012.05.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/16/2012] [Accepted: 05/24/2012] [Indexed: 02/04/2023]
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17
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Kim HA, Kim KJ, Yoon SY, Lee HK, Im SY. Glutamine inhibits platelet-activating factor-mediated pulmonary tumour metastasis. Eur J Cancer 2012; 48:1730-8. [DOI: 10.1016/j.ejca.2011.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 06/17/2011] [Accepted: 07/19/2011] [Indexed: 01/01/2023]
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18
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Freeman MR, Kim J, Lisanti MP, Di Vizio D. A metabolic perturbation by U0126 identifies a role for glutamine in resveratrol-induced cell death. Cancer Biol Ther 2011; 12:966-77. [PMID: 22108021 DOI: 10.4161/cbt.12.11.18136] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Recent evidence has identified substantial overlap between metabolic and oncogenic biochemical pathways, suggesting novel approaches to cancer intervention. For example, cholesterol lowering statins and the antidiabetes medication metformin both act as chemopreventive agents in prostate and other cancers. The natural compound resveratrol has similar properties: increasing insulin sensitivity, suppressing adipogenesis, and inducing apoptotic death of cancer cells in vitro. However, in vivo tumor xenografts acquire resistance to resveratrol by an unknown mechanism, while mouse models of metabolic disorders respond more consistently to the compound. Here we demonstrate that castration-resistant human prostate cancer C4-2 cells are more sensitive to resveratrol-induced apoptosis than isogenic androgen-dependent LNCaP cells. The MEK inhibitor U0126 antagonized resveratrol-induced apoptosis in C4-2 cells, but this effect was not seen with other MEK inhibitors. U0126 was found to inhibit mitochondrial function and shift cells to aerobic glycolysis independently of MEK. Mitochondrial activity of U0126 arose through decomposition, producing both mitochondrial fluorescence and cyanide, a known inhibitor of complex IV. Applying U0126 mitochondrial inhibition to C4-2 cell apoptosis, we tested the possibility that glutamine supplementation of citric acid cycle intermediate α-ketoglutarate may be involved. Suppression of the conversion of glutamate to α-ketoglutarate antagonized resveratrol-induced death in C4-2 cells. A similar effect was also seen by reducing extracellular glutamine concentration in the culture medium, suggesting that resveratrol-induced death is dependent on glutamine metabolism, a process frequently dysregulated in cancer. Further work on resveratrol and metabolism in cancer is warranted to ascertain if the glutamine dependence has clinical implications.
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Affiliation(s)
- Michael R Freeman
- The Urological Diseases Research Center, Children's Hospital Boston, MA, USA.
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19
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Higuera GA, Schop D, Spitters TWGM, van Dijkhuizen-Radersma R, Bracke M, de Bruijn JD, Martens D, Karperien M, van Boxtel A, van Blitterswijk CA. Patterns of amino acid metabolism by proliferating human mesenchymal stem cells. Tissue Eng Part A 2011; 18:654-64. [PMID: 21943055 DOI: 10.1089/ten.tea.2011.0223] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The nutritional requirements of stem cells have not been determined; in particular, the amino acid metabolism of stem cells is largely unknown. In this study, we investigated the amino acid metabolism of human mesenchymal stem cells (hMSCs), with focus on two questions: Which amino acids are consumed and/or secreted by hMSCs and at what rates? To answer these questions, hMSCs were cultured on tissue culture plastic and in a bioreactor, and their amino acid profile was analyzed. The results showed that the kinetics of hMSCs growth and amino acid metabolism were significantly higher for hMSCs in tissue culture plastic than in the bioreactor. Despite differences in culture conditions, 8 essential and 6 nonessential amino acids were consumed by hMSCs in both tissue culture plastic and bioreactor cultures. Glutamine was the most consumed amino acid with significantly higher rates than for any other amino acid. The metabolism of nonessential amino acids by hMSCs deviated significantly from that of other cell lines. The secretion of alanine, glycine, glutamate, and ornithine by hMSCs showed that there is a strong overflow metabolism that can be due to the high concentrations of amino acids provided in the medium. In addition, the data showed that there is a metabolic pattern for proliferating hMSCs, which can contribute to the design of medium without animal serum for stem cells. Further, this study shows how to implement amino acid rates and metabolic principles in three-dimensional stem cell biology.
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Affiliation(s)
- Gustavo A Higuera
- Department of Tissue Regeneration, University of Twente, Enschede, The Netherlands.
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20
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Stubbs M, Griffiths JR. The altered metabolism of tumors: HIF-1 and its role in the Warburg effect. ADVANCES IN ENZYME REGULATION 2009; 50:44-55. [PMID: 19896967 DOI: 10.1016/j.advenzreg.2009.10.027] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Marion Stubbs
- Cancer Research UK Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
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21
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Xue H, Sawyer MB, Field CJ, Dieleman LA, Murray D, Baracos VE. Bolus oral glutamine protects rats against CPT-11-induced diarrhea and differentially activates cytoprotective mechanisms in host intestine but not tumor. J Nutr 2008; 138:740-6. [PMID: 18356329 DOI: 10.1093/jn/138.4.740] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dietary glutamine has been suggested to preserve structural and functional integrity of the gut and high dose bolus glutamine has been hypothesized to protect against potentially fatal endotoxic shock, hyperthermic stress, and side effects of chemotherapy. In this study, we aimed to relate the ability of high dose oral bolus glutamine to mitigate the severe diarrhea induced by 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin (CPT-11) chemotherapy to specific cytoprotective mechanisms [heat shock response, glutathione (GSH)] in gut and tumor tissues. Female rats bearing Ward colon tumor received CPT-11 (125 mg x kg(-1) x d(-1)x 3 d) with or without an oral glutamine bolus (0.75 g/kg) administered 30 min prior to each CPT-11 dose. Glutamine reduced incidence and severity of late-onset diarrhea following CPT-11 treatment (P < 0.05) and was associated with potentially beneficial and protective responses in the colon: 1) a 3.1- to 7.2-fold increase of heat shock protein (Hsp)25,-70, and -90alpha (P < 0.05); 2) increased reduced GSH (rGSH):oxidized GSH ratio (P < 0.05); 3) prevention of upregulated activity of a key bacterial enzyme (beta-glucuronidase) in the cecal content that mediates CPT-11 intestinal toxicity (P < 0.05); and 4) increased proportions of CD3+CD8+ lymphocytes and memory CD8+ subset in mesenteric lymph nodes following CPT-11 therapy. By contrast, glutamine treatment did not alter CPT-11's antitumor activity, the amino acid concentrations, Hsp expression, or the ratio of rGSH:oxidized GSH in the tumor. Our data demonstrate a striking dichotomy in the response of tumor and host to oral glutamine administration, concurring with the concept that this nutrient may favorably alter the balance between the host and tumor.
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Affiliation(s)
- Hongyu Xue
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada T6G 1Z2
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22
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Samanta S, Srikanth K, Banerjee S, Debnath B, Gayen S, Jha T. 5-N-Substituted-2-(substituted benzenesulphonyl) glutamines as antitumor agents. Part II: Synthesis, biological activity and QSAR study. Bioorg Med Chem 2004; 12:1413-23. [PMID: 15018914 DOI: 10.1016/j.bmc.2004.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2003] [Accepted: 01/07/2004] [Indexed: 11/21/2022]
Abstract
Cancer is a major killer disease throughout human history. Thus, cancer becomes a major point of interest in life science. It was proved that cancer is a nitrogen trap and tumor cells are avid glutamine consumers. The non-essential amino acid glutamine, which is a glutamic acid derivative, supplies its amide nitrogen to tumor cells in the biosynthesis of purine and pyrimidine bases of nucleic acids as well as takes part in protein synthesis. Based on these and in continuation of our composite programme of development of new potential anticancer agents through rational drug design, 17 new 5-N-Substituted-2-(substituted benzenesulphonyl) glutamines were selected for synthesis. These compounds as well as 36 earlier synthesized glutamine analogues were screened for antitumor activity using percentage inhibition of tumor cell count as the activity parameter. QSAR study was performed with 53 compounds in order to design leads with increased effectiveness for antitumor activity using both physicochemical and topological parameters. QSAR study showed that steric effect on the aromatic ring is conducive to the activity. n-butyl substitution on aliphatic side chain and atom no 12 is important for antitumor activity of glutamine analogues.
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Affiliation(s)
- Soma Samanta
- Department of Pharmaceutical Technology, PO Box 17020, Jadavpur University, Kolkata-700032, India
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23
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Esumi H, Izuishi K, Kato K, Hashimoto K, Kurashima Y, Kishimoto A, Ogura T, Ozawa T. Hypoxia and nitric oxide treatment confer tolerance to glucose starvation in a 5'-AMP-activated protein kinase-dependent manner. J Biol Chem 2002; 277:32791-8. [PMID: 12091379 DOI: 10.1074/jbc.m112270200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hypoxia is a critical event for higher organisms, and cells and tissues react by increasing the oxygen supply by vasodilatation, angiogenesis, and erythropoiesis and maintaining cellular energy by increasing glycolysis and inhibiting anabolic pathways. Stimulation of glycolysis has been regarded as the main response that increases energy production during hypoxia; however, there is an obvious conflict during ischemia, because both the oxygen and glucose supply are insufficient. In this study, we found that exposure of HepG2 cells and normal fibroblasts to hypoxia induces cellular tolerance to glucose starvation. The tolerance induced by hypoxia is dependent on several amino acids, indicating a switch from glucose to amino acids as the energy source. When antisense RNA expression vector for 5'-AMP-activated protein kinase or protein kinase B/Akt was transfected into HepG2 cells, the induction of tolerance to glucose was greatly inhibited, indicating that the tolerance was dependent on 5'-AMP-activated protein kinase and protein kinase B/Akt. Similar tolerance was induced by nitric oxide exposure. The tolerance induced was observed in various cells and may represent a previously unknown physiological response related to hypoxia-preconditioning and tumor progression:austerity.
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Affiliation(s)
- Hiroyasu Esumi
- Investigative Treatment Division, National Cancer Center Research Institute East 6-5-1, Kashiwanoha, Kashiwa, Chiba, Japan.
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Abstract
Glutamine is the most abundant free amino acid in the human body; it is essential for the growth of normal and neoplastic cells and for the culture of many cell types. Cancer has been described as a nitrogen trap. The presence of a tumor produces great changes in host glutamine metabolism in such a way that host nitrogen metabolism is accommodated to the tumor-enhanced requirements of glutamine. To be used, glutamine must be transported into tumor mitochondria. Thus, an overview of the role of glutamine in cancer requires not only a discussion of host and tumor glutamine metabolism, but also its circulation and transport. Because glutamine depletion has adverse effects for the host, the effect of glutamine supplementation in the tumor-bearing state should also be studied. This communication reviews the state of knowledge of glutamine and cancer, including potential therapeutic implications.
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Affiliation(s)
- M A Medina
- Department of Molecular Biology and Biochemistry, Faculty of Sciences, University of Málaga, Málaga, Spain
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25
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Wehrle JP, Ng CE, McGovern KA, Aiken NR, Shungu DC, Chance EM, Glickson JD. Metabolism of alternative substrates and the bioenergetic status of EMT6 tumor cell spheroids. NMR IN BIOMEDICINE 2000; 13:349-360. [PMID: 11002314 DOI: 10.1002/1099-1492(200010)13:6<349::aid-nbm652>3.0.co;2-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to evaluate the ability of EMT6/Ro multicellular spheroids to utilize various pathways of energy production, (13)C and (31)P MRS have been employed to monitor the metabolism of glucose, glutamine, acetate and propionate. EMT6/Ro spheroids perfused with culture medium containing 5.5 mM glucose maintain stable levels of nucleotide triphosphates (NTP) and phosphocreatine (PCr) for up to 48 h, even in the absence of glutamine. The metabolism of 1-(13)C-glucose was almost entirely to 3-(13)C-lactate (88 +/- 12%, n = 7), even though the perfusion medium was equilibrated with 95% O(2). Labeling was also observed in other glycolytic metabolites, primarily alanine and alpha-glycerolphosphate. A low level of (13)C labeling in glutamate, indicative of mitochondrial oxidative metabolism (TCA cycle), was consistently detected when spheroids were perfused with 1-(13)C-glucose, almost exclusively in the C4 position of glutamate. Labeling of glutamate C2 and C3 was always less than 20% of the labeling in C4 and was usually undetectable. No evidence of adjacent carbon labeling in individual glutamate molecules (indicative of multiple cycles of label incorporation) was found, even in high-resolution (13)C NMR spectra of extracts from cells or spheroids. Despite the predominantly glycolytic metabolism of glucose, the mitochondrial substrate glutamine (2 mM, in the presence of < or =0.5 mM glucose from fetal bovine serum), supported stable levels of NTP and PCr in the tumor cells for up to 12 h. In the presence of 2.5 mM acetate, the bioenergetic status of cells in EMT6 spheroids declined slowly but measurably, and no incorporation of label from 2-(13)C-acetate into other metabolites was detected either in intact perfused spheroids or in high-resolution spectra of extracts. In contrast, when the anaplerotic TCA cycle substrate 3-(13)C-propionate replaced acetate, the high-energy phosphate levels in EMT6/Ro spheroids were somewhat reduced, but stabilized at a new lower level. Incubation of spheroids with 3-(13)C-propionate (with natural abundance glucose and glutamine) resulted in label detectable in the C2 and C3 of glutamate, but the primary labeled compound was methylmalonate, an intermediate in propionate metabolism. Addition of vitamin B(12), a cofactor for methylmalonyl CoA reductase, to the growth medium 24 h prior to perfusion with propionate resulted in the elimination of the methylmalonate resonance. A variety of 2- and 3-labeled metabolites were detected, including succinate, malate and glutamate. Labeling of C2 and C3 of lactate implicated cytoplasmic malic enzyme activity.
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Affiliation(s)
- J P Wehrle
- Division of NMR Research, Department of Radiology The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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26
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Collins CL, Wasa M, Souba WW, Abcouwer SF. Regulation of glutamine synthetase in human breast carcinoma cells and experimental tumors. Surgery 1997; 122:451-63; discussion 463-4. [PMID: 9288153 DOI: 10.1016/s0039-6060(97)90039-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Acute deprivation of extracellular glutamine causes up-regulation of glutamine synthetase (GS) expression by a mechanism involving an increase in GS protein stability. This study examines GS expression in a highly glutamine-dependent and tumorigenic human breast cancer cell line, TSE cells, in response to acute and chronic glutamine deprivation in culture and during tumor formation. METHODS TSE cells were subjected to acute glutamine deprivation, adapted to growth in low glutamine concentrations, and subcutaneously injected into nude mice. GS protein and mRNA levels were assayed by Western and Northern blotting, and intracellular glutamine levels were evaluated by using a colorimetric assay. RESULTS GS protein levels increased, but GS mRNA levels were unchanged in response to acute glutamine deprivation. Chronic glutamine deprivation in vitro and tumor growth in vivo caused an increase in both GS protein and mRNA levels. Large tumors exhibited lower intracellular glutamine, higher GS protein, and relatively unchanged GS mRNA levels relative to small tumors. CONCLUSIONS TSE tumors exhibit up-regulation of GS protein and mRNA levels and declines in intracellular glutamine content, suggesting that growth in vivo causes a chronic and progressive glutamine deprivation. Up-regulation of GS expression may contribute to adaptation to a nutrient-poor intratumor environment.
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Affiliation(s)
- C L Collins
- Department of Surgery, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
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27
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Bozzetti F, Biganzoli L, Gavazzi C, Cappuzzo F, Carnaghi C, Buzzoni R, Dibartolomeo M, Baietta E. Glutamine supplementation in cancer patients receiving chemotherapy: a double-blind randomized study. Nutrition 1997; 13:748-51. [PMID: 9263281 DOI: 10.1016/s0899-9007(97)83038-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study was to evaluate the efficacy of glutamine in preventing doxifluridine-induced diarrhea and the potential impact of glutamine on the tumor growth. We investigated 65 patients with advanced breast cancer receiving doxifluridine in a double-blind randomized fashion: 33 patients took glutamine (30 g/d, divided in 3 doses of 10 g each) for 8 consecutive days (5-12h) during each interval between chemotherapy, which was administered from day 1 to 4. Thirty-two patients took an equal dose of placebo (maltodextrine). The incidence of diarrhea was registered after each cycle of chemotherapy and severity was scored by the National Cancer Institute (NCI), Bethesda, Maryland, classification. The tumor response was evaluated by the World Health Organization (WHO) criteria. A total of 278 and 259 cycles (median 10 cycles), respectively, were delivered in glutamine and placebo groups. There were 34 and 32 episodes of diarrhea in glutamine and placebo groups, with no statistical difference overall, in the severity and duration of tumor growth, there was no difference in the response rate (21% and 28% of complete or partial response, respectively), in median time to response (2 mo), or in median duration of response. In conclusion, glutamine did not prevent the occurrence of the doxifluridine-induced diarrhea and did not have any impact on tumor response to chemotherapy.
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Affiliation(s)
- F Bozzetti
- Instituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy
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28
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van der Sanden BP, Rijken PF, Heerschap A, Bernsen HJ, van der Kogel AJ. In vivo (31)P magnetic resonance spectroscopy and morphometric analysis of the perfused vascular architecture of human glioma xenografts in nude mice. Br J Cancer 1997; 75:1432-8. [PMID: 9166934 PMCID: PMC2223510 DOI: 10.1038/bjc.1997.246] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The relationship between the bioenergetic status of human glioma xenografts in nude mice and morphometric parameters of the perfused vascular architecture was studied using (31)P magnetic resonance spectroscopy (MRS), fluorescence microscopy and two-dimensional digital image analysis. Two tumour lines with a different vascular architecture were used for this study. Intervascular distances and non-perfused area fractions varied greatly between tumours of the same line and tumours of different lines. The inorganic phosphate-nucleoside triphosphate (P(i)/NTP) ratio increased rapidly as mean intervascular distances increased from 100 microm to 300 microm. Two morphometric parameters - the percentage of intervascular distances larger than 200 microm (ivd200) and the non-perfused area fraction at a distance larger than 100 microm from a nearest perfused vessel (area100), - were deduced from these experiments and related to the P(i)/NTP ratio of the whole tumour. It is assumed that an aerobic to anaerobic transition influences the bioenergetic status, i.e. the P(i)/NTP ratio increased linearly with the percentage of ivd200 and the area100.
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Affiliation(s)
- B P van der Sanden
- Department of Radiology, University Hospital St Radboud, Nijmegen, The Netherlands
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29
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Rutz HP, Little JB. Exogenous lactate interferes with cell-cycle control in Balb/3T3 mouse fibroblasts. Int J Radiat Oncol Biol Phys 1995; 31:525-8. [PMID: 7852115 DOI: 10.1016/0360-3016(94)00362-o] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE Previous studies have shown that exogenous lactate may influence proliferation rates, radiation sensitivity, and postirradiation repair capacity of mammalian cells. In the present study, we addressed the question of potential underlying mechanisms and, therefore, examined effects of exogenous lactate on proliferation rates and cell-cycle distribution in immortal but nontumorigenic mammalian cells. METHODS AND MATERIALS Cells were grown at 37 degrees C in an incubator with 5% CO2 and 95% air, in a culture medium supplemented or not with lactate at a 10 mM concentration. Daily, we changed the culture medium and counted cells per dish. On selected days, cell-cycle distribution was determined by flow cytometry. Balb/3T3 mouse fibroblasts were used. RESULTS During the exponential phase of cell proliferation, mean population doubling time was significantly increased from 17.7 to 19.9 h, due to selective prolongation of G2/M. However, in density-inhibited cultures, exogenous lactate stimulated entry into S and proliferation to a significantly higher saturation density. CONCLUSIONS These findings indicate that exogenous lactate interferes with mechanisms of cell-cycle control at two different points in the cell-cycle, depending on cell density and the resulting absence or presence of inhibition of cell proliferation. Interference with cell-cycle control may underly the modification by exogenous lactate of radiosensitivity and postirradiation repair capacity in mammalian cells.
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Affiliation(s)
- H P Rutz
- Department of Cancer Biology, Harvard School of Public Health, Boston, MA 02115
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30
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Sauer LA, Dauchy RT. Lactate release and uptake in hepatoma 7288CTC perfused in situ with L-[(U)-14C]lactate or D-[(U)-14C]glucose. Metabolism 1994; 43:1488-97. [PMID: 7990701 DOI: 10.1016/0026-0495(94)90006-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Arteriovenous differences (AVD) for glucose and lactic acid measured across tissue-isolated rat tumors in vivo have shown that individual tumors with similar rates of glucose consumption may either release or utilize lactic acid. The experiments described here investigated the relationships among arterial blood lactate concentrations and tumor lactate and glucose balances. AVDs for lactate, pyruvate, glucose, 14CO2, PO2, PCO2, pH, and lactate specific activities were measured across 17 tissue-isolated 7288CTC hepatomas perfused in situ with arterial blood containing 2.5 to 14.4 mmol/L lactate and either L-[(U)-14C]lactic acid or D-[(U)-14C]glucose. Measurements were made over a range of blood flow rates from 60% to 200% of the mean in vivo rate, 0.11 mL/min. Data collected during steady states were compared by regression analysis. Tumor lactate balance and the arterial blood lactate concentration were directly related (r = .895, n = 22, P < .01). Net negative and positive balances occurred below and above approximately 6.5 mmol/L arterial blood lactate, respectively. The mean intratumor lactate concentration for all tumors was 6.9 +/- 1.0 mmol/L (mean +/- SD, n = 13). Rates of 14C-lactate oxidation to 14CO2 (r = .716, n = 18, P < .01) and tumor venous/arterial blood 14C-lactate specific activity ratios (r = .845, n = 19, P < .01) were low during lactate release and were increased during lactate uptake. Total arterial blood lactate removal estimated from chemical and isotopic analyses was 23.1% +/- 11% and 43.0% +/- 16% (P < .05), respectively, for six lactate-utilizing tumors. Perfusions performed with 14C-glucose showed that approximately 50% of the glucose consumed during net negative lactate balance was released as 14C-lactate to the tumor venous blood, whereas only 5% was released as 14C-lactate during net positive lactate balance. The data support the following conclusions: Arterial blood lactate controls net lactate balance in solid tumors; high concentrations increase uptake. Lactate uptake inhibits lactate formation from glucose without changing the glucose balance. Lactate is release during net lactate uptake. Since lactate uptake may exceed glucose uptake, arterial blood lactate can be a substrate for tumor energy metabolism and growth.
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Affiliation(s)
- L A Sauer
- Medical Research Institute, Mary Imogene Bassett Hospital, Cooperstown, NY
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31
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Hass BS, Hart RW, Lu MH, Lyn-Cook BD. Effects of caloric restriction in animals on cellular function, oncogene expression, and DNA methylation in vitro. Mutat Res 1993; 295:281-9. [PMID: 7507563 DOI: 10.1016/0921-8734(93)90026-y] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
While the life-extending and disease-modulating effects of caloric restriction (CR) are well documented in whole animal studies and in correlative experiments using cells taken from CR animals, very few studies have used cells in culture after their removal from the CR-fed animal. In using this in vivo-->in vitro approach we have attempted to examine the proposition that the effects of CR can be transferred to individual cells by analyzing the cellular functions of proliferation and transformation, the activation of oncogenes, and the methylation of DNA as a function only of diet. Pancreatic acinar cells excised from CR-fed Brown-Norway rats and placed in rich medium showed different responses compared to cells from ad libitum (AL)-fed controls. CR had the effect of slowing growth rate and protecting against spontaneous and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced transformation over 14 passages of cells in culture. At the molecular level, cells from the CR animals showed reduced c-Ha-ras oncogene expression and mutation as well as reduced mutation of the p53 suppressor gene. CR also increased genomic methylation of ras DNA. We conclude that the effects of CR treatment of the animal are transferred to individual cells and note that these responses (decreased proliferation and transformation; depressed oncogene expression and mutation and decreased suppressor gene mutation; and increased oncogene methylation) are cellular and molecular analogs of in vivo weight loss, life extension, and carcinogenesis modulation, which are hallmarks of CR in the whole animal. The fact that these responses are seen generations after the cells are removed from the CR-treated animal indicates that CR causes a permanent predisposition of pancreatic acinar cells to these modulated responses and shows the value of the in vivo-->in vitro protocol in studies that relate diet to cellular and molecular function.
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Affiliation(s)
- B S Hass
- Division of Nutritional Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079
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32
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Abstract
Depletion of skeletal muscle mass in animals bearing an experimental model of cachexia, the MAC16 adenocarcinoma, occurs by a reduction in protein synthesis accompanied by a large increase in protein degradation. Serum from mice bearing the MAC16 tumour produced an increased protein degradation in isolated gastrocnemius muscle, as measured by tyrosine release, with a maximal effect occurring with serum from animals with a weight loss of between 11 and 20%. The response was specific to the cachectic state, since serum from mice bearing the MAC13 adenocarcinoma, which does not produce weight loss, did not increase tyrosine release from gastrocnemius muscle above that observed with serum from non tumour-bearing animals. The circulatory proteolysis-inducing factor was stable to heating at 60 degrees C for 5 min and was not inhibited by phenylmethylsulfonyl fluoride, suggesting that it was not a serine protease. The level of prostaglandin E2 (PGE2) in gastrocnemius muscle was significantly elevated after incubation with serum from cachectic mice bearing the MAC16 tumour. Both indomethacin and the polyunsaturated fatty acid eicosapentaenoic acid (EPA) inhibited the rise in muscle PGE2 content in response to serum from cachectic mice and also inhibited muscle protein degradation. These results suggest that muscle protein degradation in cancer cachexia is associated with a rise in PGE2 content.
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Affiliation(s)
- K L Smith
- Pharmaceutical Sciences Institute, Aston University, Birmingham, UK
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33
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Medina MA, Sánchez-Jiménez F, Márquez J, Rodríguez Quesada A, Núñez de Castro I. Relevance of glutamine metabolism to tumor cell growth. Mol Cell Biochem 1992; 113:1-15. [PMID: 1640933 DOI: 10.1007/bf00230880] [Citation(s) in RCA: 146] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- M A Medina
- Laboratorio de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Málaga, Spain
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13C-Leucine-tracer-technique for in-vivo measurement of amino acids' metabolism by human colon carcinomas. Amino Acids 1991; 1:283-7. [DOI: 10.1007/bf00806927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Nguyen DT, Keast D. Energy metabolism and the skin. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1991; 23:1175-83. [PMID: 1794442 DOI: 10.1016/0020-711x(91)90213-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- D T Nguyen
- Department of Microbiology, University of Western Australia, Nedlands
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Nguyen TD, Keast D. The effects of diet on the maximal activities of glutaminase, citrate synthase, hexokinase, 6-phosphofructokinase and lactate dehydrogenase in the skin of haired and hairless mice of various ages. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1991; 23:365-9. [PMID: 1828443 DOI: 10.1016/0020-711x(91)90120-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
1. The maximal activities of hexokinase (HK), 6-phosphofructokinase (PFK), lactate dehydrogenase (LDH), citrate synthase (CS) and glutaminase (GLU) which provide a quantitative indices of flux through several important pathways have been measured in the skin of haired Balb/c and hairless Balb/c (nu/nu) mice under normal and dietary stress. 2. The skin of old haired mice exhibited higher PFK and LDH activities with lower HK, CS and GLU activities. All activities of enzymes associated with energy metabolism in the skin of old hairless mice were higher than those in the skin of haired mice. 3. HK, LDH, CS and GLU activities were maintained at normal levels in the skin of haired mice when these mice were fed diets deficient in energy or protein components (HPLE, LPNE). These enzymes however were severely suppressed when mice were fed a diet deficient in both energy and protein components (LPLE). Recovery of activities of these enzymes to the control level was observed when mice were refed with the normal diet for a week.
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Affiliation(s)
- T D Nguyen
- Department of Microbiology, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands
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Abstract
The filarial parasites that affect humans most seriously include Onchocerca volvulus, Wuchereria bancrofti, Brugia malayi and Loa loa. In general, these species cause disease that is debilitating long before it is fatal, producing clinical manifestations such as general malaise, pruritus and lichenification of the skin, lymphangitis, elephantiasis and blindness(1). As a result, infection with any one of these organisms is physically, as well as economically, devastating. Currently, the pharmacological armamentarium with which to treat filarial infections is very limited and many of the drugs that are known to be efficacious against these worms may produce side effects that cause extreme discomfort. Here, Elizabeth Vande Waa describes the quest for new chemotherapeutic approaches for the treatment of filarial infections.
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Affiliation(s)
- E A Vande Waa
- Department of Comparative Biosciences, School of Veterinary Medicine, 2015 Linden Drive West, University of Wisconsin, Madison, WI 53706, USA
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MacKenzie NE, Van de Waa EA, Gooley PR, Williams JF, Bennett JL, Bjorge SM, Baille TA, Geary TG. Comparison of glycolysis and glutaminolysis in Onchocerca volvulus and Brugia pahangi by 13C nuclear magnetic resonance spectroscopy. Parasitology 1989; 99 Pt 3:427-35. [PMID: 2608314 DOI: 10.1017/s0031182000059151] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Comparison of glycolysis in Brugia pahangi and Onchocerca volvulus by 13C nuclear magnetic resonance (NMR) spectroscopy showed that the former organism is predominantly a lactate fermenter and the latter resembles more closely the metabolism of a mixed acid fermenter producing lactate, succinate, acetate, ethanol, formate and carbon dioxide. Both organisms synthesize glycogen as a storage carbohydrate. Glutaminolysis in both organisms proceeds by the delta-amino-butyrate shunt to produce succinate which is then further metabolized to acetate and carbon dioxide as end-products.
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Affiliation(s)
- N E MacKenzie
- Department of Pharmaceutical Sciences, University of Arizona, Tucson 85721
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Nomura T, Rubin H. Quantitative studies of amino acid and growth factor requirements of transformed and nontransformed cells in high concentrations of serum or lymph. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 1988; 24:878-84. [PMID: 3170445 DOI: 10.1007/bf02623897] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The growth rate of spontaneously transformed BALB/3T3 cells is proportional to glutamine concentration between 50 and 400 microM, with little or no growth occurring in less than 50 microM glutamine. By contrast, nontransformed BALB/3T3 cells multiply, although slowly, with as little as 20 microM glutamine. Neither cell type depletes the medium of glutamine at the low concentrations. Cystine requirements of both cell types increase with serum concentration, probably due to the binding of half-cystine residues by the serum. Calf serum is a much more potent stimulator of cell multiplication than calf lymph, especially for the nontransformed cells. The rate of cell multiplication can be reduced by lowering the concentration of essential amino acids to the physiologic level found in body fluids, but the growth limitations can be fully compensated by simply raising the serum concentration. Growth factors may act by enhancing the utilization of amino acids, particularly of glutamine which is a required substrate for the first and chief regulatory steps of purine and pyrimidine synthesis. Lymph, which is coextensive with interstitial fluid in vivo, is poor in growth factors for the nontransformed BALB/3T3 cells as well as for recently explanted mouse embryo cells, which raises questions of how normal cell growth is maintained in the body.
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Affiliation(s)
- T Nomura
- Department of Molecular Biology and Virus Laboratory, University of California, Berkeley
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Abstract
Spontaneous mammary tumours of the rat with various degrees of malignancy exhibit similar tissue pH distributions. The mean pH (+/- s.d.) of dysplasia is 7.05 +/- 0.20. In benign tumours the mean pH is 6.95 +/- 0.19 and in malignant tumours it is 6.94 +/- 0.19. In contrast, tumours with the same degree of malignancy but different histologies show different pH distributions. Benign tumours with a higher percentage of fibrous tissue exhibit less acidic pH values than those with larger portions of epithelial cells (delta pH = 0.38 pH units). The pH distribution in the benign tumours is independent of the tumour wet weight up to stages of very advanced growth. In the malignant tumours, a trend towards more acidic pH values is observed as the tumour mass enlarges. However, in tissue areas within a malignant tumour with gross, long-established necrosis the pH distribution is shifted towards more alkaline pH values. The pH distributions in spontaneous rat tumours are not significantly different from those obtained in isotransplanted Yoshida sarcomas (6.87 +/- 0.21). In the Yoshida sarcomas, mean pH values do not correlate with tumour size. However, a pH gradient from the rim to the centre of the tumours is found which coincides with the development of small, disseminated necroses in the tumour centre. It is concluded that pathology-related variations of tumour pH may be more important than the mode of tumour origin or the degree of malignancy.
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Affiliation(s)
- F Kallinowski
- Department of Applied Physiology, University of Mainz, Federal Republic of Germany
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Marx E, Mueller-Klieser W, Vaupel P. Lactate-induced inhibition of tumor cell proliferation. Int J Radiat Oncol Biol Phys 1988; 14:947-55. [PMID: 3360660 DOI: 10.1016/0360-3016(88)90017-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Culture medium that was recovered from tumor cell or fibroblast cultures during the plateau phase, and that was replenished by addition of glucose, glutamine, and serum and readjustment of pH had a distinct growth-inhibiting effect on monolayer cell cultures. The effect, which was not specific for a given cell strain, may be partially responsible for the "density inhibition" commonly observed in malignant cells grown in monolayer cultures. By modifying fresh growth media, it was shown that the growth inhibition observed can be partly attributed to the accumulation of lactate in the culture medium of plateau phase cells. This substance reduced the plating efficiency and the number of cells per petri dish in the plateau phase. It is concluded that this effect may be used for inducing growth inhibition in tumors in vivo by manipulating the cellular production of lactate and/or by impeding its removal from the cellular microenvironment.
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Affiliation(s)
- E Marx
- Dept. of Applied Physiology, University of Mainz, Fed. Rep. Germany
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