ROS signaling by NOX4 drives fibroblast-to-myofibroblast differentiation in the diseased prostatic stroma

Mol Endocrinol. 2011 Mar;25(3):503-15. doi: 10.1210/me.2010-0340. Epub 2011 Jan 27.


Stromal remodeling, in particular fibroblast-to-myofibroblast differentiation, is a hallmark of benign prostatic hyperplasia (BPH) and solid tumors, including prostate cancer (PCa). Increased local production of TGFβ1 is considered the inducing stimulus. Given that stromal remodeling actively promotes BPH/PCa development, there is considerable interest in developing stromal-targeted therapies. Microarray and quantitative PCR analysis of primary human prostatic stromal cells induced to undergo fibroblast-to-myofibroblast differentiation with TGFβ1 revealed up-regulation of the reactive oxygen species (ROS) producer reduced nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) and down-regulation of the selenium-containing ROS-scavenging enzymes glutathione peroxidase 3, thioredoxin reductase 1 (TXNRD1), and the selenium transporter selenoprotein P plasma 1. Consistently, NOX4 expression correlated specifically with the myofibroblast phenotype in vivo, and loss of selenoprotein P plasma 1 was observed in tumor-associated stroma of human PCa biopsies. Using lentiviral NOX4 short hairpin RNA-mediated knockdown, pharmacological inhibitors, antioxidants, and selenium, we demonstrate that TGFβ1 induction of NOX4-derived ROS is required for TGFβ1-mediated phosphorylation of c-jun N-terminal kinase, which in turn is essential for subsequent downstream cytoskeletal remodeling. Significantly, selenium supplementation inhibited differentiation by increasing ROS-scavenging selenoenzyme biosynthesis because glutathione peroxidase 3 and TXNRD1 expression and TXNRD1 enzyme activity were restored. Consistently, selenium depleted ROS levels downstream of NOX4 induction. Collectively, this work demonstrates that dysregulated redox homeostasis driven by elevated NOX4-derived ROS signaling underlies fibroblast-to-myofibroblast differentiation in the diseased prostatic stroma. Further, these data indicate the potential clinical value of selenium and/or NOX4 inhibitors in preventing the functional pathogenic changes of stromal cells in BPH and PCa.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Cell Differentiation / drug effects
  • Cell Differentiation / genetics
  • Cell Line
  • Fibroblasts / cytology*
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • Humans
  • Immunohistochemistry
  • Male
  • Myofibroblasts / cytology*
  • Myofibroblasts / drug effects
  • Myofibroblasts / metabolism
  • NADPH Oxidase 4
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism*
  • Oligonucleotide Array Sequence Analysis
  • Polymerase Chain Reaction
  • Reactive Oxygen Species / metabolism*
  • Signal Transduction / drug effects
  • Transforming Growth Factor beta1 / pharmacology


  • Reactive Oxygen Species
  • Transforming Growth Factor beta1
  • NADPH Oxidase 4
  • NADPH Oxidases
  • NOX4 protein, human