Oxidative metabolism drives inflammation-induced platinum resistance in human ovarian cancer

Cell Death Differ. 2016 Sep 1;23(9):1542-54. doi: 10.1038/cdd.2016.39. Epub 2016 May 20.

Abstract

Tumour cells have long been considered defective in mitochondrial respiration and mostly dependent on glycolytic metabolism. However, this assumption is currently challenged by several lines of evidence in a growing number of tumours. Ovarian cancer (OC) is one of the most lethal cancers worldwide, but it continues to be a poorly understood disease and its metabolic features are far to be elucidated. In this context, we investigated the role of tumour necrosis factor receptor-associated protein 1 (TRAP1), which is found upregulated in several cancer types and is a key modulator of tumour cell metabolism. Surprisingly, we found that TRAP1 expression inversely correlated with grade, stage and lower survival in a large cohort of OC patients. Accordingly, TRAP1 silencing induced resistance to cisplatin, resistant cells showed increased oxidative metabolism compared with their sensitive counterpart, and the bioenergetics cellular index of higher grade tumours indicated increased mitochondrial respiration. Strikingly, cisplatin resistance was reversible upon pharmacological inhibition of mitochondrial oxidative phosphorylation by metformin/oligomycin. At molecular level, increased oxidative metabolism in low TRAP1-expressing OC cells and tissues enhanced production of inflammatory mediators such as interleukin (IL)-6 and IL-8. Mechanistically, we identified members of the multidrug resistance complex (MDR) as key mediators of such metabolism-driven, inflammation-induced process. Indeed, treatment of OC cell lines with TNFα and IL6 induced a selective increase in the expression of TAP1 and multidrug resistance protein 1, whereas TAP1 silencing sensitized cells to cisplatin-induced apoptosis. Our results unveil a novel role for TRAP1 and oxidative metabolism in cancer progression and suggest the targeting of mitochondrial bioenergetics to increase cisplatin efficacy in human OC.

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / metabolism
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cisplatin / pharmacology
  • Cisplatin / therapeutic use*
  • Disease-Free Survival
  • Drug Resistance, Neoplasm*
  • Female
  • Glycolysis
  • HSP90 Heat-Shock Proteins / antagonists & inhibitors
  • HSP90 Heat-Shock Proteins / genetics
  • HSP90 Heat-Shock Proteins / metabolism
  • Humans
  • Immediate-Early Proteins / genetics
  • Immediate-Early Proteins / metabolism
  • Inflammation / metabolism
  • Inflammation / pathology*
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism
  • Metformin / pharmacology
  • Ovarian Neoplasms / drug therapy*
  • Ovarian Neoplasms / mortality
  • Ovarian Neoplasms / pathology
  • Oxidative Phosphorylation / drug effects
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism

Substances

  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • HSP90 Heat-Shock Proteins
  • Immediate-Early Proteins
  • Interleukin-6
  • Interleukin-8
  • RNA, Small Interfering
  • TRAP1 protein, human
  • Metformin
  • Protein Serine-Threonine Kinases
  • serum-glucocorticoid regulated kinase
  • Cisplatin