Elucidating cancer metabolic plasticity by coupling gene regulation with metabolic pathways

Proc Natl Acad Sci U S A. 2019 Feb 26;116(9):3909-3918. doi: 10.1073/pnas.1816391116. Epub 2019 Feb 7.

Abstract

Metabolic plasticity enables cancer cells to switch their metabolism phenotypes between glycolysis and oxidative phosphorylation (OXPHOS) during tumorigenesis and metastasis. However, it is still largely unknown how cancer cells orchestrate gene regulation to balance their glycolysis and OXPHOS activities. Previously, by modeling the gene regulation of cancer metabolism we have reported that cancer cells can acquire a stable hybrid metabolic state in which both glycolysis and OXPHOS can be used. Here, to comprehensively characterize cancer metabolic activity, we establish a theoretical framework by coupling gene regulation with metabolic pathways. Our modeling results demonstrate a direct association between the activities of AMPK and HIF-1, master regulators of OXPHOS and glycolysis, respectively, with the activities of three major metabolic pathways: glucose oxidation, glycolysis, and fatty acid oxidation. Our model further characterizes the hybrid metabolic state and a metabolically inactive state where cells have low activity of both glycolysis and OXPHOS. We verify the model prediction using metabolomics and transcriptomics data from paired tumor and adjacent benign tissue samples from a cohort of breast cancer patients and RNA-sequencing data from The Cancer Genome Atlas. We further validate the model prediction by in vitro studies of aggressive triple-negative breast cancer (TNBC) cells. The experimental results confirm that TNBC cells can maintain a hybrid metabolic phenotype and targeting both glycolysis and OXPHOS is necessary to eliminate their metabolic plasticity. In summary, our work serves as a platform to symmetrically study how tuning gene activity modulates metabolic pathway activity, and vice versa.

Keywords: OXPHOS; TNBC; Warburg; hybrid; metabolic reprogramming.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • AMP-Activated Protein Kinases / genetics*
  • AMP-Activated Protein Kinases / metabolism
  • Cell Line, Tumor
  • Fatty Acids / metabolism
  • Female
  • Glucose / metabolism
  • Glycolysis / genetics
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics*
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Metabolic Networks and Pathways / genetics*
  • Mitochondria / metabolism
  • Models, Theoretical
  • Oxidative Phosphorylation
  • Triple Negative Breast Neoplasms / genetics*
  • Triple Negative Breast Neoplasms / metabolism
  • Triple Negative Breast Neoplasms / pathology

Substances

  • Fatty Acids
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • PRKAA1 protein, human
  • AMP-Activated Protein Kinases
  • Glucose