title: IDH1 Mutation Induces Reprogramming of Pyruvate Metabolism.
abstract: Mutant isocitrate dehydrogenase 1 (IDH1) catalyzes the production of 2-hydroxyglutarate but also elicits additional metabolic changes. Levels of both glutamate and pyruvate dehydrogenase (PDH) activity have been shown to be affected in U87 glioblastoma cells or normal human astrocyte (NHA) cells expressing mutant IDH1, as compared with cells expressing wild-type IDH1. In this study, we show how these phenomena are linked through the effects of IDH1 mutation, which also reprograms pyruvate metabolism. Reduced PDH activity in U87 glioblastoma and NHA IDH1 mutant cells was associated with relative increases in PDH inhibitory phosphorylation, expression of pyruvate dehydrogenase kinase-3, and levels of hypoxia inducible factor-1α. PDH activity was monitored in these cells by hyperpolarized (13)C-magnetic resonance spectroscopy ((13)C-MRS), which revealed a reduction in metabolism of hyperpolarized 2-(13)C-pyruvate to 5-(13)C-glutamate, relative to cells expressing wild-type IDH1. (13)C-MRS also revealed a reduction in glucose flux to glutamate in IDH1 mutant cells. Notably, pharmacological activation of PDH by cell exposure to dichloroacetate (DCA) increased production of hyperpolarized 5-(13)C-glutamate in IDH1 mutant cells. Furthermore, DCA treatment also abrogated the clonogenic advantage conferred by IDH1 mutation. Using patient-derived mutant IDH1 neurosphere models, we showed that PDH activity was essential for cell proliferation. Taken together, our results established that the IDH1 mutation induces an MRS-detectable reprogramming of pyruvate metabolism, which is essential for cell proliferation and clonogenicity, with immediate therapeutic implications.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Jose L
authors.initials: JL
authors.lastname: Izquierdo-Garcia
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Pavithra
authors.initials: P
authors.lastname: Viswanath
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Pia
authors.initials: P
authors.lastname: Eriksson
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Larry
authors.initials: L
authors.lastname: Cai
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Marina
authors.initials: M
authors.lastname: Radoul
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Myriam M
authors.initials: MM
authors.lastname: Chaumeil
authors.affiliation: Department of Clinical Neurosciences and Southern Alberta Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Blough
authors.affiliation: Department of Cell Biology and Anatomy and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
authors.forename: H Artee
authors.initials: HA
authors.lastname: Luchman
authors.affiliation: Department of Clinical Neurosciences and Southern Alberta Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Samuel
authors.initials: S
authors.lastname: Weiss
authors.affiliation: Department of Clinical Neurosciences and Southern Alberta Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada.
authors.forename: J Gregory
authors.initials: JG
authors.lastname: Cairncross
authors.affiliation: Department of Neurological Surgery, Helen Diller Research Center, University of California San Francisco, San Francisco, California.
authors.forename: Joanna J
authors.initials: JJ
authors.lastname: Phillips
authors.affiliation: Department of Neurological Surgery, Helen Diller Research Center, University of California San Francisco, San Francisco, California.
authors.forename: Russell O
authors.initials: RO
authors.lastname: Pieper
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California. sabrina.ronen@ucsf.edu.
authors.forename: Sabrina M
authors.initials: SM
authors.lastname: Ronen
mesh_terms: D001253:Astrocytes / Q000378:metabolism; D045744:Cell Line, Tumor / Q000187:drug effects; D049109:Cell Proliferation; D003999:Dichloroacetic Acid / Q000494:pharmacology; D015536:Down-Regulation; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D005977:Glutarates / Q000378:metabolism; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009154:Mutation; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism*; D011773:Pyruvates / Q000378:metabolism*
chemical_list: D005977:Glutarates; D011768:Pyruvate Dehydrogenase Complex; D011773:Pyruvates; C019417:alpha-hydroxyglutarate; D018698:Glutamic Acid; D003999:Dichloroacetic Acid; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human