Expression of a mutant prohibitin from the aP2 gene promoter leads to obesity-linked tumor development in insulin resistance-dependent manner

Oncogene. 2016 Aug 25;35(34):4459-70. doi: 10.1038/onc.2015.501. Epub 2016 Jan 11.

Abstract

A critical unmet need for the study of obesity-linked cancer is the lack of preclinical models that spontaneously develop obesity and cancer sequentially. Prohibitin (PHB) is a pleiotropic protein that has a role in adipose and immune functions. We capitalized on this attribute of PHB to develop a mouse model for obesity-linked tumor. We achieved this by expressing Y114F-PHB (m-PHB) from the aP2 gene promoter for simultaneous manipulation of adipogenic and immune signaling functions. The m-PHB mice develop obesity in a sex-neutral manner, but only male mice develop impaired glucose homeostasis and hyperinsulinemia similar to transgenic mice expressing PHB. Interestingly, only male m-PHB mice develop histiocytosis with lymphadenopathy, suggesting that metabolic dysregulation or m-PHB alone is not sufficient for the tumor development and that both are required for tumorigenesis. Moreover, ovariectomy in female m-PHB mice resulted in impaired glucose homeostasis, hyperinsulinemia and consequently tumor development similar to male m-PHB mice. These changes were not observed in sham-operated control m-Mito-Ob mice, further confirming the role of obesity-related metabolic dysregulation in tumor development in m-PHB mice. Our data provide a proof-of-concept that obesity-associated hyperinsulinemia promotes tumor development by facilitating dormant mutant to manifest and reveals a sex-dimorphic role of PHB in adipose-immune interaction or immunometabolism. Targeting PHB may provide a unique opportunity for the modulation of immunometabolism in obesity, cancer and in immune diseases.

MeSH terms

  • Adipokines / blood
  • Animals
  • Cells, Cultured
  • Chemokines / blood
  • Cytokines / blood
  • Fatty Acid-Binding Proteins / genetics*
  • Female
  • Histiocytosis / etiology
  • Hyperinsulinism / complications
  • Insulin Resistance*
  • Lymphadenopathy / etiology
  • Male
  • Mice
  • Mutation
  • Neoplasms / etiology*
  • Obesity / complications*
  • Prohibitins
  • Promoter Regions, Genetic*
  • Repressor Proteins / genetics
  • Repressor Proteins / physiology*
  • Sex Characteristics

Substances

  • Adipokines
  • Chemokines
  • Cytokines
  • Fabp4 protein, mouse
  • Fatty Acid-Binding Proteins
  • Prohibitins
  • Repressor Proteins