Activation of androgen receptor, lipogenesis, and oxidative stress converged by SREBP-1 is responsible for regulating growth and progression of prostate cancer cells

Mol Cancer Res. 2012 Jan;10(1):133-42. doi: 10.1158/1541-7786.MCR-11-0206. Epub 2011 Nov 7.

Abstract

We previously reported that sterol regulatory element-binding protein-1 (SREBP-1) is involved in the transcriptional regulation of androgen receptor (AR) and formation of fatty acid through altered expression of fatty acid synthase (FASN). In this article, we provide a new finding that SREBP-1 induced oxidative stress in prostate cancer cells through increased production of reactive oxygen species (ROS) and expression of NADPH oxidase 5 (Nox5). We have shown that (i) expression of SREBP-1 protein is positively associated with the clinical Gleason grades in human prostate cancer; (ii) genetic overexpression or knockdown of SREBP-1 in prostate cancer cells resulted in corresponding increased or decreased AR, FASN and Nox5 expression, fatty acid and lipid droplet accumulation, and ROS generation; and (iii) SREBP-1 induces and promotes the growth, migration, invasion, and castration-resistant progression of prostate cancer cells in vitro and in vivo. Our data show a novel molecular mechanism by which SREBP-1 promotes prostate cancer growth and progression through alterations in the concerted intracellular metabolic and signaling networks involving AR, lipogenesis, and ROS in prostate cancer cells.

Publication types

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

MeSH terms

  • Animals
  • Carcinoma / genetics
  • Carcinoma / metabolism
  • Carcinoma / pathology*
  • Cell Growth Processes / genetics*
  • Disease Progression
  • Humans
  • Lipogenesis / genetics*
  • Lipogenesis / physiology
  • Male
  • Mice
  • Mice, Nude
  • Oxidative Stress / genetics*
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology*
  • Reactive Oxygen Species / metabolism
  • Receptors, Androgen / metabolism*
  • Receptors, Androgen / physiology
  • Sterol Regulatory Element Binding Protein 1 / genetics
  • Sterol Regulatory Element Binding Protein 1 / metabolism
  • Sterol Regulatory Element Binding Protein 1 / physiology*
  • Transcriptional Activation / genetics
  • Transplantation, Heterologous
  • Tumor Cells, Cultured

Substances

  • AR protein, human
  • Reactive Oxygen Species
  • Receptors, Androgen
  • SREBF1 protein, human
  • Sterol Regulatory Element Binding Protein 1