MUC16-mediated activation of mTOR and c-Myc reprograms pancreatic cancer metabolism

Oncotarget. 2015 Aug 7;6(22):19118-31. doi: 10.18632/oncotarget.4078.

Abstract

MUC16, a transmembrane mucin, facilitates pancreatic adenocarcinoma progression and metastasis. In the current studies, we observed that MUC16 knockdown pancreatic cancer cells exhibit reduced glucose uptake and lactate secretion along with reduced migration and invasion potential, which can be restored by supplementing the culture media with lactate, an end product of aerobic glycolysis. MUC16 knockdown leads to inhibition of mTOR activity and reduced expression of its downstream target c-MYC, a key player in cellular growth, proliferation and metabolism. Ectopic expression of c-MYC in MUC16 knockdown pancreatic cancer cells restores the altered cellular physiology. Our LC-MS/MS based metabolomics studies indicate global metabolic alterations in MUC16 knockdown pancreatic cancer cells, as compared to the controls. Specifically, glycolytic and nucleotide metabolite pools were significantly decreased. We observed similar metabolic alterations that correlated with MUC16 expression in primary tumor tissue specimens from human pancreatic adenocarcinoma cancer patients. Overall, our results demonstrate that MUC16 plays an important role in metabolic reprogramming of pancreatic cancer cells by increasing glycolysis and enhancing motility and invasiveness.

Keywords: MUC16; c-MYC; metabolism; metabolomics; pancreatic cancer.

Publication types

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

MeSH terms

  • CA-125 Antigen / genetics
  • CA-125 Antigen / metabolism*
  • Cell Line, Tumor
  • Cell Movement / physiology
  • Cell Proliferation / physiology
  • Gene Knockdown Techniques
  • Glucose / metabolism
  • Humans
  • Lactic Acid / metabolism
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Neoplasm Invasiveness
  • Pancreatic Neoplasms / genetics
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • Proto-Oncogene Proteins c-myc / biosynthesis
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*
  • TOR Serine-Threonine Kinases / genetics
  • TOR Serine-Threonine Kinases / metabolism*
  • Transfection

Substances

  • CA-125 Antigen
  • MUC16 protein, human
  • MYC protein, human
  • Membrane Proteins
  • Proto-Oncogene Proteins c-myc
  • Lactic Acid
  • MTOR protein, human
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases
  • Glucose