MYC/PGC-1α Balance Determines the Metabolic Phenotype and Plasticity of Pancreatic Cancer Stem Cells

Cell Metab. 2015 Oct 6;22(4):590-605. doi: 10.1016/j.cmet.2015.08.015. Epub 2015 Sep 10.

Abstract

The anti-diabetic drug metformin targets pancreatic cancer stem cells (CSCs), but not their differentiated progenies (non-CSCs), which may be related to distinct metabolic phenotypes. Here we conclusively demonstrate that while non-CSCs were highly glycolytic, CSCs were dependent on oxidative metabolism (OXPHOS) with very limited metabolic plasticity. Thus, mitochondrial inhibition, e.g., by metformin, translated into energy crisis and apoptosis. However, resistant CSC clones eventually emerged during treatment with metformin due to their intermediate glycolytic/respiratory phenotype. Mechanistically, suppression of MYC and subsequent increase of PGC-1α were identified as key determinants for the OXPHOS dependency of CSCs, which was abolished in resistant CSC clones. Intriguingly, no resistance was observed for the mitochondrial ROS inducer menadione and resistance could also be prevented/reversed for metformin by genetic/pharmacological inhibition of MYC. Thus, the specific metabolic features of pancreatic CSCs are amendable to therapeutic intervention and could provide the basis for developing more effective therapies to combat this lethal cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AC133 Antigen
  • Animals
  • Antigens, CD
  • Antineoplastic Agents / therapeutic use
  • Drug Resistance, Neoplasm
  • Gene Library
  • Glycoproteins
  • Humans
  • Metformin / therapeutic use
  • Metformin / toxicity
  • Mice
  • Mice, Nude
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Neoplastic Stem Cells / cytology
  • Neoplastic Stem Cells / metabolism
  • Oxidative Phosphorylation / drug effects
  • Pancreatic Neoplasms / drug therapy
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • Peptides
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Phenotype
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*
  • RNA Interference
  • Reactive Oxygen Species / metabolism
  • Transcription Factors / antagonists & inhibitors
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Tumor Cells, Cultured
  • Vitamin K 3 / pharmacology

Substances

  • AC133 Antigen
  • Antigens, CD
  • Antineoplastic Agents
  • Glycoproteins
  • PPARGC1A protein, human
  • Peptides
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Proto-Oncogene Proteins c-myc
  • Reactive Oxygen Species
  • Transcription Factors
  • Vitamin K 3
  • Metformin