COX-2 mediates pro-tumorigenic effects of PKCε in prostate cancer

Oncogene. 2018 Aug;37(34):4735-4749. doi: 10.1038/s41388-018-0318-9. Epub 2018 May 16.

Abstract

The pro-oncogenic kinase PKCε is overexpressed in human prostate cancer and cooperates with loss of the tumor suppressor Pten for the development of prostatic adenocarcinoma. However, the effectors driving PKCε-mediated phenotypes remain poorly defined. Here, using cellular and mouse models, we showed that PKCε overexpression acts synergistically with Pten loss to promote NF-κB activation and induce cyclooxygenase-2 (COX-2) expression, phenotypic traits which are also observed in human prostate tumors. Targeted disruption of PKCε from prostate cancer cells impaired COX-2 induction and PGE2 production. Notably, COX-2 inhibitors selectively killed prostate epithelial cells overexpressing PKCε, and this ability was greatly enhanced by Pten loss. Long-term COX-2 inhibition markedly reduced adenocarcinoma formation, as well as angiogenesis in a mouse model of prostate-specific PKCε expression and Pten loss. Overall, our results provide strong evidence for the involvement of the canonical NF-κB pathway and its target gene COX2 as PKCε effectors, and highlight the potential of PKCε as a useful biomarker for the use of COX inhibition for chemopreventive and/or chemotherapeutic purposes in prostate cancer.

Publication types

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

MeSH terms

  • Adenocarcinoma / genetics
  • Adenocarcinoma / pathology
  • Animals
  • Carcinogenesis / genetics*
  • Cell Line, Tumor
  • Cyclooxygenase 2 / genetics*
  • Humans
  • Male
  • Mice
  • NF-kappa B / genetics
  • Prostate / pathology
  • Prostatic Neoplasms / genetics*
  • Prostatic Neoplasms / pathology
  • Protein Kinase C-epsilon / genetics*
  • Signal Transduction / genetics

Substances

  • NF-kappa B
  • Cyclooxygenase 2
  • Protein Kinase C-epsilon