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Targeting Glucose Metabolism of Cancer Cells with Dichloroacetate to Radiosensitize High-Grade Gliomas. Int J Mol Sci 2021; 22:7265. [PMID: 34298883 PMCID: PMC8305417 DOI: 10.3390/ijms22147265;] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
As the cornerstone of high-grade glioma (HGG) treatment, radiotherapy temporarily controls tumor cells via inducing oxidative stress and subsequent DNA breaks. However, almost all HGGs recur within months. Therefore, it is important to understand the underlying mechanisms of radioresistance, so that novel strategies can be developed to improve the effectiveness of radiotherapy. While currently poorly understood, radioresistance appears to be predominantly driven by altered metabolism and hypoxia. Glucose is a central macronutrient, and its metabolism is rewired in HGG cells, increasing glycolytic flux to produce energy and essential metabolic intermediates, known as the Warburg effect. This altered metabolism in HGG cells not only supports cell proliferation and invasiveness, but it also contributes significantly to radioresistance. Several metabolic drugs have been used as a novel approach to improve the radiosensitivity of HGGs, including dichloroacetate (DCA), a small molecule used to treat children with congenital mitochondrial disorders. DCA reverses the Warburg effect by inhibiting pyruvate dehydrogenase kinases, which subsequently activates mitochondrial oxidative phosphorylation at the expense of glycolysis. This effect is thought to block the growth advantage of HGGs and improve the radiosensitivity of HGG cells. This review highlights the main features of altered glucose metabolism in HGG cells as a contributor to radioresistance and describes the mechanism of action of DCA. Furthermore, we will summarize recent advances in DCA's pre-clinical and clinical studies as a radiosensitizer and address how these scientific findings can be translated into clinical practice to improve the management of HGG patients.
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Cook KM, Shen H, McKelvey KJ, Gee HE, Hau E. Targeting Glucose Metabolism of Cancer Cells with Dichloroacetate to Radiosensitize High-Grade Gliomas. Int J Mol Sci 2021; 22:ijms22147265. [PMID: 34298883 PMCID: PMC8305417 DOI: 10.3390/ijms22147265] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 02/06/2023] Open
Abstract
As the cornerstone of high-grade glioma (HGG) treatment, radiotherapy temporarily controls tumor cells via inducing oxidative stress and subsequent DNA breaks. However, almost all HGGs recur within months. Therefore, it is important to understand the underlying mechanisms of radioresistance, so that novel strategies can be developed to improve the effectiveness of radiotherapy. While currently poorly understood, radioresistance appears to be predominantly driven by altered metabolism and hypoxia. Glucose is a central macronutrient, and its metabolism is rewired in HGG cells, increasing glycolytic flux to produce energy and essential metabolic intermediates, known as the Warburg effect. This altered metabolism in HGG cells not only supports cell proliferation and invasiveness, but it also contributes significantly to radioresistance. Several metabolic drugs have been used as a novel approach to improve the radiosensitivity of HGGs, including dichloroacetate (DCA), a small molecule used to treat children with congenital mitochondrial disorders. DCA reverses the Warburg effect by inhibiting pyruvate dehydrogenase kinases, which subsequently activates mitochondrial oxidative phosphorylation at the expense of glycolysis. This effect is thought to block the growth advantage of HGGs and improve the radiosensitivity of HGG cells. This review highlights the main features of altered glucose metabolism in HGG cells as a contributor to radioresistance and describes the mechanism of action of DCA. Furthermore, we will summarize recent advances in DCA’s pre-clinical and clinical studies as a radiosensitizer and address how these scientific findings can be translated into clinical practice to improve the management of HGG patients.
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Affiliation(s)
- Kristina M. Cook
- Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia; (H.S.); (K.J.M.); (H.E.G.); (E.H.)
- Correspondence: ; Tel.: +61-286274858
| | - Han Shen
- Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia; (H.S.); (K.J.M.); (H.E.G.); (E.H.)
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead 2145, Australia
| | - Kelly J. McKelvey
- Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia; (H.S.); (K.J.M.); (H.E.G.); (E.H.)
- Bill Walsh Translational Cancer Research Laboratory, Kolling Institute, Faculty of Medicine and Health, University of Sydney, St. Leonards 2065, Australia
| | - Harriet E. Gee
- Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia; (H.S.); (K.J.M.); (H.E.G.); (E.H.)
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead 2145, Australia
- Sydney West Radiation Oncology Network, University of Sydney, Sydney 2006, Australia
- Children’s Medical Research Institute, Westmead 2145, Australia
| | - Eric Hau
- Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia; (H.S.); (K.J.M.); (H.E.G.); (E.H.)
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead 2145, Australia
- Sydney West Radiation Oncology Network, University of Sydney, Sydney 2006, Australia
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Dichloroacetate Radiosensitizes Hypoxic Breast Cancer Cells. Int J Mol Sci 2020; 21:ijms21249367. [PMID: 33316932 PMCID: PMC7763818 DOI: 10.3390/ijms21249367] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 12/29/2022] Open
Abstract
Mitochondrial metabolism is an attractive target for cancer therapy. Reprogramming metabolic pathways can potentially sensitize tumors with limited treatment options, such as triple-negative breast cancer (TNBC), to chemo- and/or radiotherapy. Dichloroacetate (DCA) is a specific inhibitor of the pyruvate dehydrogenase kinase (PDK), which leads to enhanced reactive oxygen species (ROS) production. ROS are the primary effector molecules of radiation and an increase hereof will enhance the radioresponse. In this study, we evaluated the effects of DCA and radiotherapy on two TNBC cell lines, namely EMT6 and 4T1, under aerobic and hypoxic conditions. As expected, DCA treatment decreased phosphorylated pyruvate dehydrogenase (PDH) and lowered both extracellular acidification rate (ECAR) and lactate production. Remarkably, DCA treatment led to a significant increase in ROS production (up to 15-fold) in hypoxic cancer cells but not in aerobic cells. Consistently, DCA radiosensitized hypoxic tumor cells and 3D spheroids while leaving the intrinsic radiosensitivity of the tumor cells unchanged. Our results suggest that although described as an oxidative phosphorylation (OXPHOS)-promoting drug, DCA can also increase hypoxic radioresponses. This study therefore paves the way for the targeting of mitochondrial metabolism of hypoxic cancer cells, in particular to combat radioresistance.
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Shen H, Cook K, Gee HE, Hau E. Hypoxia, metabolism, and the circadian clock: new links to overcome radiation resistance in high-grade gliomas. J Exp Clin Cancer Res 2020; 39:129. [PMID: 32631383 PMCID: PMC7339573 DOI: 10.1186/s13046-020-01639-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 07/01/2020] [Indexed: 02/07/2023] Open
Abstract
Radiotherapy is the cornerstone of treatment of high-grade gliomas (HGGs). It eradicates tumor cells by inducing oxidative stress and subsequent DNA damage. Unfortunately, almost all HGGs recur locally within several months secondary to radioresistance with intricate molecular mechanisms. Therefore, unravelling specific underlying mechanisms of radioresistance is critical to elucidating novel strategies to improve the radiosensitivity of tumor cells, and enhance the efficacy of radiotherapy. This review addresses our current understanding of how hypoxia and the hypoxia-inducible factor 1 (HIF-1) signaling pathway have a profound impact on the response of HGGs to radiotherapy. In addition, intriguing links between hypoxic signaling, circadian rhythms and cell metabolism have been recently discovered, which may provide insights into our fundamental understanding of radioresistance. Cellular pathways involved in the hypoxic response, DNA repair and metabolism can fluctuate over 24-h periods due to circadian regulation. These oscillatory patterns may have consequences for tumor radioresistance. Timing radiotherapy for specific times of the day (chronoradiotherapy) could be beneficial in patients with HGGs and will be discussed.
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Affiliation(s)
- Han Shen
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead, New South Wales, 2145, Australia.
- Sydney Medical School, University of Sydney, Camperdown, New South Wales, Australia.
| | - Kristina Cook
- Sydney Medical School, University of Sydney, Camperdown, New South Wales, Australia
- Faculty of Medicine and Health & Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Harriet E Gee
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead, New South Wales, 2145, Australia
- Sydney Medical School, University of Sydney, Camperdown, New South Wales, Australia
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Westmead, New South Wales, Australia
| | - Eric Hau
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, Westmead Institute for Medical Research, Westmead, New South Wales, 2145, Australia
- Sydney Medical School, University of Sydney, Camperdown, New South Wales, Australia
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Westmead, New South Wales, Australia
- Blacktown Hematology and Cancer Centre, Blacktown Hospital, Blacktown, New South Wales, Australia
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Stakišaitis D, Juknevičienė M, Damanskienė E, Valančiūtė A, Balnytė I, Alonso MM. The Importance of Gender-Related Anticancer Research on Mitochondrial Regulator Sodium Dichloroacetate in Preclinical Studies In Vivo. Cancers (Basel) 2019; 11:cancers11081210. [PMID: 31434295 PMCID: PMC6721567 DOI: 10.3390/cancers11081210] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/16/2019] [Accepted: 08/16/2019] [Indexed: 12/28/2022] Open
Abstract
Sodium dichloroacetate (DCA) is an investigational medicinal product which has a potential anticancer preparation as a metabolic regulator in cancer cells’ mitochondria. Inhibition of pyruvate dehydrogenase kinases by DCA keeps the pyruvate dehydrogenase complex in the active form, resulting in decreased lactic acid in the tumor microenvironment. This literature review displays the preclinical research data on DCA’s effects on the cell pyruvate dehydrogenase deficiency, pyruvate mitochondrial oxidative phosphorylation, reactive oxygen species generation, and the Na+–K+–2Cl− cotransporter expression regulation in relation to gender. It presents DCA pharmacokinetics and the hepatocarcinogenic effect, and the safety data covers the DCA monotherapy efficacy for various human cancer xenografts in vivo in male and female animals. Preclinical cancer researchers report the synergistic effects of DCA combined with different drugs on cancer by reversing resistance to chemotherapy and promoting cell apoptosis. Researchers note that female and male animals differ in the mechanisms of cancerogenesis but often ignore studying DCA’s effects in relation to gender. Preclinical gender-related differences in DCA pharmacology, pharmacological mechanisms, and the elucidation of treatment efficacy in gonad hormone dependency could be relevant for individualized therapy approaches so that gender-related differences in treatment response and safety can be proposed.
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Affiliation(s)
- Donatas Stakišaitis
- Laboratory of Molecular Oncology, National Cancer Institute, 08660 Vilnius, Lithuania.
- Department of Histology and Embryology, Medical Academy, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania.
| | - Milda Juknevičienė
- Department of Histology and Embryology, Medical Academy, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
| | - Eligija Damanskienė
- Department of Histology and Embryology, Medical Academy, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
| | - Angelija Valančiūtė
- Department of Histology and Embryology, Medical Academy, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
| | - Ingrida Balnytė
- Department of Histology and Embryology, Medical Academy, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
| | - Marta Maria Alonso
- Department of Pediatrics, Clínica Universidad de Navarra, University of Navarra, 55 Pamplona, Spain.
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Wang G, Wang JJ, Guan R, Sun Y, Shi F, Gao J, Fu XL. Targeting Strategies for Glucose Metabolic Pathways and T Cells in Colorectal Cancer. Curr Cancer Drug Targets 2018; 19:534-550. [PMID: 30360743 DOI: 10.2174/1568009618666181015150138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 11/23/2017] [Accepted: 12/24/2017] [Indexed: 11/22/2022]
Abstract
Colorectal cancer is a heterogeneous group of diseases that result from the accumulation of different sets of genomic alterations, together with epigenomic alterations, and it is influenced by tumor-host interactions, leading to tumor cell growth and glycolytic imbalances. This review summarizes recent findings that involve multiple signaling molecules and downstream genes in the dysregulated glycolytic pathway. This paper further discusses the role of the dysregulated glycolytic pathway in the tumor initiation, progression and the concomitant systemic immunosuppression commonly observed in colorectal cancer patients. Moreover, the relationship between colorectal cancer cells and T cells, especially CD8+ T cells, is discussed, while different aspects of metabolic pathway regulation in cancer cell proliferation are comprehensively defined. Furthermore, this study elaborates on metabolism in colorectal cancer, specifically key metabolic modulators together with regulators, glycolytic enzymes, and glucose deprivation induced by tumor cells and how they inhibit T-cell glycolysis and immunogenic functions. Moreover, metabolic pathways that are integral to T cell function, differentiation, and activation are described. Selective metabolic inhibitors or immunemodulation agents targeting these pathways may be clinically useful to increase effector T cell responses for colorectal cancer treatment. However, there is a need to identify specific antigens using a cancer patient-personalized approach and combination strategies with other therapeutic agents to effectively target tumor metabolic pathways.
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Affiliation(s)
- Gang Wang
- Department of Pharmaceutics, Shanghai Eighth People's Hospital, Jiangsu University, 200235, Shanghai, China
| | - Jun-Jie Wang
- Department of Pharmaceutics, Shanghai Eighth People's Hospital, Jiangsu University, 200235, Shanghai, China
| | - Rui Guan
- Hubei University of Medicine, NO. 30 People South Road, Shiyan City, Hubei Province 442000, China
| | - Yan Sun
- Hubei University of Medicine, NO. 30 People South Road, Shiyan City, Hubei Province 442000, China
| | - Feng Shi
- Department of Medicine, Jiangsu University, Zhenjiang City, Jiangsu Province 212001, China
| | - Jing Gao
- Department of Medicine, Jiangsu University, Zhenjiang City, Jiangsu Province 212001, China
| | - Xing-Li Fu
- Department of Medicine, Jiangsu University, Zhenjiang City, Jiangsu Province 212001, China
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Fang S, Fang X. Advances in glucose metabolism research in colorectal cancer. Biomed Rep 2016; 5:289-295. [PMID: 27602209 PMCID: PMC4998148 DOI: 10.3892/br.2016.719] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 07/06/2016] [Indexed: 12/12/2022] Open
Abstract
Cancer cells uptake glucose at a higher rate and produce lactic acid rather than metabolizing pyruvate through the tricarboxylic acid cycle. This adaptive metabolic shift is termed the Warburg effect. Recently progress had been made regarding the mechanistic understanding of glucose metabolism and associated diagnostic and therapeutic methods, which have been investigated in colorectal cancer. The majority of novel mechanisms involve important glucose metabolism associated genes and miRNA regulation. The present review discusses the contribution of these research results to facilitate with the development of novel diagnosis and anticancer treatment options.
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Affiliation(s)
- Sitian Fang
- Key Laboratory of Biotherapy of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang 310016, P.R. China; Hangzhou No. 4 High School, Hangzhou, Zhejiang 310018, P.R. China
| | - Xiao Fang
- Key Laboratory of Biotherapy of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang 310016, P.R. China; Department of Anesthesiology, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang 310016, P.R. China
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8
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Jha MK, Lee IK, Suk K. Metabolic reprogramming by the pyruvate dehydrogenase kinase-lactic acid axis: Linking metabolism and diverse neuropathophysiologies. Neurosci Biobehav Rev 2016; 68:1-19. [PMID: 27179453 DOI: 10.1016/j.neubiorev.2016.05.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/11/2016] [Accepted: 05/09/2016] [Indexed: 12/12/2022]
Abstract
Emerging evidence indicates that there is a complex interplay between metabolism and chronic disorders in the nervous system. In particular, the pyruvate dehydrogenase (PDH) kinase (PDK)-lactic acid axis is a critical link that connects metabolic reprogramming and the pathophysiology of neurological disorders. PDKs, via regulation of PDH complex activity, orchestrate the conversion of pyruvate either aerobically to acetyl-CoA, or anaerobically to lactate. The kinases are also involved in neurometabolic dysregulation under pathological conditions. Lactate, an energy substrate for neurons, is also a recently acknowledged signaling molecule involved in neuronal plasticity, neuron-glia interactions, neuroimmune communication, and nociception. More recently, the PDK-lactic acid axis has been recognized to modulate neuronal and glial phenotypes and activities, contributing to the pathophysiologies of diverse neurological disorders. This review covers the recent advances that implicate the PDK-lactic acid axis as a novel linker of metabolism and diverse neuropathophysiologies. We finally explore the possibilities of employing the PDK-lactic acid axis and its downstream mediators as putative future therapeutic strategies aimed at prevention or treatment of neurological disorders.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea; Department of Neurology, Division of Neuromuscular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - In-Kyu Lee
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
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Allen KT, Chin-Sinex H, DeLuca T, Pomerening JR, Sherer J, Watkins JB, Foley J, Jesseph JM, Mendonca MS. Dichloroacetate alters Warburg metabolism, inhibits cell growth, and increases the X-ray sensitivity of human A549 and H1299 NSC lung cancer cells. Free Radic Biol Med 2015; 89:263-73. [PMID: 26393423 DOI: 10.1016/j.freeradbiomed.2015.08.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 07/02/2015] [Accepted: 08/06/2015] [Indexed: 12/22/2022]
Abstract
We investigated whether altering Warburg metabolism (aerobic glycolysis) by treatment with the metabolic agent dichloroacetate (DCA) could increase the X-ray-induced cell killing of the radiation-resistant human non-small-cell lung cancer (NSCLC) cell lines A549 and H1299. Treatment with 50mM DCA decreased lactate production and glucose consumption in both A549 and H1299, clear indications of attenuated aerobic glycolysis. In addition, we found that DCA treatment also slowed cell growth, increased population-doubling time, and altered cell cycle distribution. Furthermore, we report that treatment with 50mM DCA significantly increased single and fractionated X-ray-induced cell killing of A549 and H1299 cells. Assay of DNA double-strand break repair by neutral comet assays demonstrated that DCA inhibited both the fast and the slow kinetics of X-ray-induced DSB repair in both A549 and H1299 NSCL cancer cells. Taken together the data suggest a correlation between an attenuated aerobic glycolysis and enhanced cytotoxicity and radiation-induced cell killing in radiation-resistant NSCLC cells.
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Affiliation(s)
- Kah Tan Allen
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
| | - Helen Chin-Sinex
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Thomas DeLuca
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | | | - Jeremy Sherer
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - John B Watkins
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
| | - John Foley
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA; Department of Dermatology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Indiana University Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Jerry M Jesseph
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
| | - Marc S Mendonca
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Indiana University Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Womeldorff M, Gillespie D, Jensen RL. Hypoxia-inducible factor-1 and associated upstream and downstream proteins in the pathophysiology and management of glioblastoma. Neurosurg Focus 2015; 37:E8. [PMID: 25581937 DOI: 10.3171/2014.9.focus14496] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with an exceptionally poor patient outcome despite aggressive therapy including surgery, radiation, and chemotherapy. This aggressive phenotype may be associated with intratumoral hypoxia, which probably plays a key role in GBM tumor growth, development, and angiogenesis. A key regulator of cellular response to hypoxia is the protein hypoxia-inducible factor–1 (HIF-1). An examination of upstream hypoxic and nonhypoxic regulation of HIF-1 as well as a review of the downstream HIF-1– regulated proteins may provide further insight into the role of this transcription factor in GBM pathophysiology. Recent insights into upstream regulators that intimately interact with HIF-1 could provide potential therapeutic targets for treatment of this tumor. The same is potentially true for HIF-1–mediated pathways of glycolysis-, angiogenesis-, and invasion-promoting proteins. Thus, an understanding of the relationship between HIF-1, its upstream protein regulators, and its downstream transcribed genes in GBM pathogenesis could provide future treatment options for the care of patients with these tumors.
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Shen H, Hau E, Joshi S, Dilda PJ, McDonald KL. Sensitization of Glioblastoma Cells to Irradiation by Modulating the Glucose Metabolism. Mol Cancer Ther 2015; 14:1794-804. [PMID: 26063767 DOI: 10.1158/1535-7163.mct-15-0247] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 06/03/2015] [Indexed: 11/16/2022]
Abstract
Because radiotherapy significantly increases median survival in patients with glioblastoma, the modulation of radiation resistance is of significant interest. High glycolytic states of tumor cells are known to correlate strongly with radioresistance; thus, the concept of metabolic targeting needs to be investigated in combination with radiotherapy. Metabolically, the elevated glycolysis in glioblastoma cells was observed postradiotherapy together with upregulated hypoxia-inducible factor (HIF)-1α and its target pyruvate dehydrogenase kinase 1 (PDK1). Dichloroacetate, a PDK inhibitor currently being used to treat lactic acidosis, can modify tumor metabolism by activating mitochondrial activity to force glycolytic tumor cells into oxidative phosphorylation. Dichloroacetate alone demonstrated modest antitumor effects in both in vitro and in vivo models of glioblastoma and has the ability to reverse the radiotherapy-induced glycolytic shift when given in combination. In vitro, an enhanced inhibition of clonogenicity of a panel of glioblastoma cells was observed when dichloroacetate was combined with radiotherapy. Further mechanistic investigation revealed that dichloroacetate sensitized glioblastoma cells to radiotherapy by inducing the cell-cycle arrest at the G2-M phase, reducing mitochondrial reserve capacity, and increasing the oxidative stress as well as DNA damage in glioblastoma cells together with radiotherapy. In vivo, the combinatorial treatment of dichloroacetate and radiotherapy improved the survival of orthotopic glioblastoma-bearing mice. In conclusion, this study provides the proof of concept that dichloroacetate can effectively sensitize glioblastoma cells to radiotherapy by modulating the metabolic state of tumor cells. These findings warrant further evaluation of the combination of dichloroacetate and radiotherapy in clinical trials.
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Affiliation(s)
- Han Shen
- Cure Brain Cancer Neuro-Oncology Group, Adult Cancer Program, Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Eric Hau
- Cure Brain Cancer Neuro-Oncology Group, Adult Cancer Program, Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia. Cancer Care Centre, St George Hospital, Kogarah, New South Wales, Australia
| | - Swapna Joshi
- Cure Brain Cancer Neuro-Oncology Group, Adult Cancer Program, Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Pierre J Dilda
- Tumour Metabolism Group, Adult Cancer Program, Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Kerrie L McDonald
- Cure Brain Cancer Neuro-Oncology Group, Adult Cancer Program, Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
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Yoo H, Kang JW, Lee DW, Oh SH, Lee YS, Lee EJ, Cho J. Pyruvate metabolism: A therapeutic opportunity in radiation-induced skin injury. Biochem Biophys Res Commun 2015; 460:504-10. [PMID: 25797627 DOI: 10.1016/j.bbrc.2015.03.060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 03/11/2015] [Indexed: 11/18/2022]
Abstract
Ionizing radiation is used to treat a range of cancers. Despite recent technological progress, radiation therapy can damage the skin at the administration site. The specific molecular mechanisms involved in this effect have not been fully characterized. In this study, the effects of pyruvate, on radiation-induced skin injury were investigated, including the role of the pyruvate dehydrogenase kinase 2 (PDK2) signaling pathway. Next generation sequencing (NGS) identified a wide range of gene expression differences between the control and irradiated mice, including reduced expression of PDK2. This was confirmed using Q-PCR. Cell culture studies demonstrated that PDK2 overexpression and a high cellular pyruvate concentration inhibited radiation-induced cytokine expression. Immunohistochemical studies demonstrated radiation-induced skin thickening and gene expression changes. Oral pyruvate treatment markedly downregulated radiation-induced changes in skin thickness and inflammatory cytokine expression. These findings indicated that regulation of the pyruvate metabolic pathway could provide an effective approach to the control of radiation-induced skin damage.
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Affiliation(s)
- Hyun Yoo
- Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea
| | - Jeong Wook Kang
- Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea
| | - Dong Won Lee
- Department of Plastic Surgery, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea
| | - Sang Ho Oh
- Department of Dermatology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea
| | - Yun-Sil Lee
- College of Pharmacy & Division of Life and Pharmaceutical Sciences, Ewah Womans University, Seoul 120-750, South Korea
| | - Eun-Jung Lee
- Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea
| | - Jaeho Cho
- Department of Radiation Oncology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, South Korea.
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Mitochondrial induction as a potential radio-sensitizer in lung cancer cells - a short report. Cell Oncol (Dordr) 2015; 38:247-52. [DOI: 10.1007/s13402-014-0212-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2014] [Indexed: 01/16/2023] Open
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McCarty MF, Contreras F. Increasing Superoxide Production and the Labile Iron Pool in Tumor Cells may Sensitize Them to Extracellular Ascorbate. Front Oncol 2014; 4:249. [PMID: 25279352 PMCID: PMC4165285 DOI: 10.3389/fonc.2014.00249] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 09/01/2014] [Indexed: 12/23/2022] Open
Abstract
Low millimolar concentrations of ascorbate are capable of inflicting lethal damage on a high proportion of cancer cells lines, yet leave non-transformed cell lines unscathed. Extracellular generation of hydrogen peroxide, reflecting reduction of molecular oxygen by ascorbate, has been shown to mediate this effect. Although some cancer cell lines express low catalase activity, this cannot fully explain the selective sensitivity of cancer cells to hydrogen peroxide. Ranzato and colleagues have presented evidence for a plausible new explanation of this sensitivity - a high proportion of cancers, via NADPH oxidase complexes or dysfunctional mitochondria, produce elevated amounts of superoxide. This superoxide, via a transition metal-catalyzed transfer of an electron to the hydrogen peroxide produced by ascorbate, can generate deadly hydroxyl radical (Haber-Weiss reaction). It thus can be predicted that concurrent measures which somewhat selectively boost superoxide production in cancers will enhance their sensitivity to i.v. ascorbate therapy. One way to achieve this is to increase the provision of substrate to cancer mitochondria. Measures which inhibit the constitutive hypoxia-inducible factor-1 (HIF-1) activity in cancers (such as salsalate and mTORC1 inhibitors, or an improvement of tumor oxygenation), or that inhibit the HIF-1-inducible pyruvate dehydrogenase kinase (such as dichloroacetate), can be expected to increase pyruvate oxidation. A ketogenic diet should provide more lipid substrate for tumor mitochondria. The cancer-killing activity of 42°C hyperthermia is to some degree contingent on an increase in oxidative stress, likely of mitochondrial origin; reports that hydrogen peroxide synergizes with hyperthermia in killing cancer cells suggest that hyperthermia and i.v. ascorbate could potentiate each other's efficacy. A concurrent enhancement of tumor oxygenation might improve results by decreasing HIF-1 activity while increasing the interaction of ascorbic acid with oxygen. An increased pool of labile iron in cancer cells may contribute to the selective susceptibility of many cancers to i.v. ascorbate; antagonism of NF-kappaB activity with salicylate, and intravenous iron administration, could be employed to further elevate free iron in cancers.
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Kankotia S, Stacpoole PW. Dichloroacetate and cancer: new home for an orphan drug? Biochim Biophys Acta Rev Cancer 2014; 1846:617-29. [PMID: 25157892 DOI: 10.1016/j.bbcan.2014.08.005] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/15/2014] [Accepted: 08/18/2014] [Indexed: 02/06/2023]
Abstract
We reviewed the anti-cancer effects of DCA, an orphan drug long used as an investigational treatment for various acquired and congenital disorders of mitochondrial intermediary metabolism. Inhibition by DCA of mitochondrial pyruvate dehydrogenase kinases and subsequent reactivation of the pyruvate dehydrogenase complex and oxidative phosphorylation is the common mechanism accounting for the drug's anti-neoplastic effects. At least two fundamental changes in tumor metabolism are induced by DCA that antagonize tumor growth, metastases and survival: the first is the redirection of glucose metabolism from glycolysis to oxidation (reversal of the Warburg effect), leading to inhibition of proliferation and induction of caspase-mediated apoptosis. These effects have been replicated in both human cancer cell lines and in tumor implants of diverse germ line origin. The second fundamental change is the oxidative removal of lactate, via pyruvate, and the co-incident buffering of hydrogen ions by dehydrogenases located in the mitochondrial matrix. Preclinical studies demonstrate that DCA has additive or synergistic effects when used in combination with standard agents designed to modify tumor oxidative stress, vascular remodeling, DNA integrity or immunity. These findings and limited clinical results suggest that potentially fruitful areas for additional clinical trials include 1) adult and pediatric high grade astrocytomas; 2) BRAF-mutant cancers, such as melanoma, perhaps combined with other pro-oxidants; 3) tumors in which resistance to standard platinum-class drugs alone may be overcome with combination therapy; and 4) tumors of endodermal origin, in which extensive experimental research has demonstrated significant anti-proliferative, pro-apoptotic effects of DCA, leading to improved host survival.
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Affiliation(s)
- Shyam Kankotia
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida College of Medicine, Gainesville, FL, United States
| | - Peter W Stacpoole
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida College of Medicine, Gainesville, FL, United States; Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL, United States.
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Jha MK, Suk K. Pyruvate dehydrogenase kinase as a potential therapeutic target for malignant gliomas. Brain Tumor Res Treat 2013; 1:57-63. [PMID: 24904893 PMCID: PMC4027103 DOI: 10.14791/btrt.2013.1.2.57] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 08/14/2013] [Accepted: 09/23/2013] [Indexed: 12/18/2022] Open
Abstract
Metabolic aberrations in the form of altered flux through key metabolic pathways are the major hallmarks of several life-threatening malignancies including malignant gliomas. These adaptations play an important role in the enhancement of the survival and proliferation of gliomas at the expense of the surrounding normal/healthy tissues. Recent studies in the field of neurooncology have directly targeted the altered metabolic pathways of malignant tumor cells for the development of anti-cancer drugs. Aerobic glycolysis due to elevated production of lactate from pyruvate regardless of oxygen availability is a common metabolic alteration in most malignancies. Aerobic glycolysis offers survival advantages in addition to generating substrates such as fatty acids, amino acids and nucleotides required for the rapid proliferation of cells. This review outlines the role of pyruvate dehydrogenase kinase (PDK) in gliomas as an inhibitor of pyruvate dehydrogenase that catalyzes the oxidative decarboxylation of pyruvate. An in-depth investigation on the key metabolic enzyme PDK may provide a novel therapeutic approach for the treatment of malignant gliomas.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science & Engineering Institute, Kyungpook National University School of Medicine, Daegu, Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science & Engineering Institute, Kyungpook National University School of Medicine, Daegu, Korea
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