title: Cancer-associated isocitrate dehydrogenase 1 (IDH1) R132H mutation and d-2-hydroxyglutarate stimulate glutamine metabolism under hypoxia.
abstract: Mutations in the cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDH1) occur in several types of cancer, and altered cellular metabolism associated with IDH1 mutations presents unique therapeutic opportunities. By altering IDH1, these mutations target a critical step in reductive glutamine metabolism, the metabolic pathway that converts glutamine ultimately to acetyl-CoA for biosynthetic processes. While IDH1-mutated cells are sensitive to therapies that target glutamine metabolism, the effect of IDH1 mutations on reductive glutamine metabolism remains poorly understood. To explore this issue, we investigated the effect of a knock-in, single-codon IDH1-R132H mutation on the metabolism of the HCT116 colorectal adenocarcinoma cell line. Here we report the R132H-isobolome by using targeted (13)C isotopomer tracer fate analysis to trace the metabolic fate of glucose and glutamine in this system. We show that introduction of the R132H mutation into IDH1 up-regulates the contribution of glutamine to lipogenesis in hypoxia, but not in normoxia. Treatment of cells with a d-2-hydroxyglutarate (d-2HG) ester recapitulated these changes, indicating that the alterations observed in the knocked-in cells were mediated by d-2HG produced by the IDH1 mutant. These studies provide a dynamic mechanistic basis for metabolic alterations observed in IDH1-mutated tumors and uncover potential therapeutic targets in IDH1-mutated cancers.
authors.affiliation: From the Department of Pathology, the Department of Medicine, MedStar Union Memorial Hospital, Baltimore, Maryland 21218.
authors.forename: Zachary J
authors.initials: ZJ
authors.lastname: Reitman
authors.affiliation: From the Department of Pathology.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Duncan
authors.affiliation: the Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107.
authors.forename: Ethan
authors.initials: E
authors.lastname: Poteet
authors.affiliation: the Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107.
authors.forename: Ali
authors.initials: A
authors.lastname: Winters
authors.affiliation: the Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107.
authors.forename: Liang-Jun
authors.initials: LJ
authors.lastname: Yan
authors.affiliation: Small Molecule Synthesis Facility, Department of Chemistry, and.
authors.forename: David M
authors.initials: DM
authors.lastname: Gooden
authors.affiliation: the Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710.
authors.forename: Ivan
authors.initials: I
authors.lastname: Spasojevic
authors.affiliation: SIDMAP, LLC, Los Angeles, California 90064, and Department of Pediatrics, Los Angeles Biomedical Research Institute, Harbor-UCLA Medical Center, Torrance, California 90502.
authors.forename: Laszlo G
authors.initials: LG
authors.lastname: Boros
authors.affiliation: the Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas 76107, shaohua.yang@unthsc.edu.
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Yang
authors.affiliation: From the Department of Pathology, hai.yan@dm.duke.edu.
authors.forename: Hai
authors.initials: H
authors.lastname: Yan
mesh_terms: D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D005977:Glutarates / Q000378:metabolism*; D006019:Glycolysis; D045325:HCT116 Cells; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D008928:Mitochondria / Q000502:physiology; D009369:Neoplasms / Q000201:enzymology* / Q000473:pathology
chemical_list: D005977:Glutarates; C019417:alpha-hydroxyglutarate; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human
keywords: Cell Metabolism; Glutamine; Metabolic Tracer; Metabolomics; Tumor Metabolism