In Vivo Imaging of Glutamine Metabolism to the Oncometabolite 2-Hydroxyglutarate in IDH1/2 Mutant Tumors

Cell Metab. 2017 Dec 5;26(6):830-841.e3. doi: 10.1016/j.cmet.2017.10.001. Epub 2017 Oct 19.

Abstract

The oncometabolite 2-hydroxyglutarate (2-HG) is a signature biomarker in various cancers, where it accumulates as a result of mutations in isocitrate dehydrogenase (IDH). The metabolic source of 2-HG, in a wide variety of cancers, dictates both its generation and also potential therapeutic strategies, but this remains difficult to access in vivo. Here, utilizing patient-derived chondrosarcoma cells harboring endogenous mutations in IDH1 and IDH2, we report that 2-HG can be rapidly generated from glutamine in vitro. Then, using hyperpolarized magnetic resonance imaging (HP-MRI), we demonstrate that in vivo HP [1-13C] glutamine can be used to non-invasively measure glutamine-derived HP 2-HG production. This can be readily modulated utilizing a selective IDH1 inhibitor, opening the door to targeting glutamine-derived 2-HG therapeutically. Rapid rates of HP 2-HG generation in vivo further demonstrate that, in a context-dependent manner, glutamine can be a primary carbon source for 2-HG production in mutant IDH tumors.

Keywords: 2-hydroxyglutarate; glutamine; hyperpolarized imaging; mutant isocitrate dehydrogenase.

MeSH terms

  • Animals
  • Biomarkers, Tumor / metabolism*
  • Bone Neoplasms / diagnostic imaging*
  • Bone Neoplasms / genetics
  • Bone Neoplasms / metabolism
  • Cell Line, Tumor
  • Chondrosarcoma / diagnostic imaging*
  • Chondrosarcoma / genetics
  • Chondrosarcoma / metabolism
  • Female
  • Glutamine / metabolism*
  • Glutarates / metabolism*
  • Humans
  • Isocitrate Dehydrogenase / genetics*
  • Magnetic Resonance Imaging
  • Male
  • Mice, SCID
  • Mutation
  • Xenograft Model Antitumor Assays

Substances

  • Biomarkers, Tumor
  • Glutarates
  • Glutamine
  • alpha-hydroxyglutarate
  • IDH2 protein, human
  • Isocitrate Dehydrogenase
  • IDH1 protein, human