MYC-Regulated Mevalonate Metabolism Maintains Brain Tumor-Initiating Cells

Cancer Res. 2017 Sep 15;77(18):4947-4960. doi: 10.1158/0008-5472.CAN-17-0114. Epub 2017 Jul 20.

Abstract

Metabolic dysregulation drives tumor initiation in a subset of glioblastomas harboring isocitrate dehydrogenase (IDH) mutations, but metabolic alterations in glioblastomas with wild-type IDH are poorly understood. MYC promotes metabolic reprogramming in cancer, but targeting MYC has proven notoriously challenging. Here, we link metabolic dysregulation in patient-derived brain tumor-initiating cells (BTIC) to a nexus between MYC and mevalonate signaling, which can be inhibited by statin or 6-fluoromevalonate treatment. BTICs preferentially express mevalonate pathway enzymes, which we find regulated by novel MYC-binding sites, validating an additional transcriptional activation role of MYC in cancer metabolism. Targeting mevalonate activity attenuated RAS-ERK-dependent BTIC growth and self-renewal. In turn, mevalonate created a positive feed-forward loop to activate MYC signaling via induction of miR-33b. Collectively, our results argue that MYC mediates its oncogenic effects in part by altering mevalonate metabolism in glioma cells, suggesting a therapeutic strategy in this setting. Cancer Res; 77(18); 4947-60. ©2017 AACR.

MeSH terms

  • Animals
  • Apoptosis
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism
  • Brain Neoplasms / genetics
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology*
  • Cell Proliferation
  • Cell Transformation, Neoplastic / metabolism
  • Cell Transformation, Neoplastic / pathology*
  • Glioblastoma / genetics
  • Glioblastoma / metabolism
  • Glioblastoma / pathology*
  • Humans
  • Isocitrate Dehydrogenase / metabolism
  • Mevalonic Acid / metabolism*
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • MicroRNAs / genetics
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology*
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Signal Transduction / drug effects
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays

Substances

  • Biomarkers, Tumor
  • MIRN33a microRNA, human
  • MicroRNAs
  • Proto-Oncogene Proteins c-myc
  • Isocitrate Dehydrogenase
  • Mevalonic Acid