The c-Myc-LDHA axis positively regulates aerobic glycolysis and promotes tumor progression in pancreatic cancer

Med Oncol. 2015 Jul;32(7):187. doi: 10.1007/s12032-015-0633-8. Epub 2015 May 29.

Abstract

The transcription factor c-Myc plays critical roles in cancer development and progression through regulating expression of targeted genes. Lactate dehydrogenase A (LDHA), which catalyzes the conversion of L-lactate to pyruvate in the final step of anaerobic glycolysis, is frequently upregulated in pancreatic cancer. However, little is known about the effects of c-Myc-LDHA axis in the progression of pancreatic cancer. In this study, we found that c-Myc and LDHA are concomitantly overexpressed in pancreatic cancer cell lines and clinical specimens. c-Myc overexpression and LDHA overexpression were correlated with TNM stage and tumor size and indicated poor prognosis in patients with pancreatic cancer. Knockdown of c-Myc reduced the protein expression of LDHA, lactate production and glucose consumption, and silencing of LDHA mimicked this effect. Meanwhile, reduced c-Myc-LDHA signaling resulted in decreased tumor growth and metastasis in pancreatic cancer. Treatment with 2-Deoxy-D-glucose, an inhibitor of anaerobic glycolysis, completely blocked the oncogenic roles of c-Myc-LDHA signaling. Taken together, dysregulated c-Myc-LDHA signaling plays important roles in aerobic glycolysis and facilitates tumor progression of pancreatic cancer.

MeSH terms

  • Cell Line, Tumor
  • Disease Progression
  • Female
  • Glucose / genetics
  • Glycolysis / genetics*
  • Humans
  • Isoenzymes / genetics
  • L-Lactate Dehydrogenase / genetics*
  • Lactate Dehydrogenase 5
  • Male
  • Middle Aged
  • Pancreatic Neoplasms / genetics*
  • Pancreatic Neoplasms / pathology*
  • Proto-Oncogene Proteins c-myc / genetics*
  • Signal Transduction / genetics
  • Up-Regulation / genetics

Substances

  • Isoenzymes
  • Proto-Oncogene Proteins c-myc
  • L-Lactate Dehydrogenase
  • Lactate Dehydrogenase 5
  • Glucose