Downregulation of Dickkopf-3 disrupts prostate acinar morphogenesis through TGF-β/Smad signalling

Diana Romero1, Yoshiaki Kawano, Nora Bengoa

  • 1Department of Surgery and Cancer, Imperial College London, London, W12 0NN, UK.

Journal of Cell Science
|February 28, 2013
PubMed

Insights

The tumor suppressor Dickkopf-3 (Dkk-3) is crucial for maintaining prostate tissue organization. Loss of Dkk-3 leads to increased cell proliferation and disrupted tissue structure by activating TGF-β/Smad signaling.

Area of Science:

  • Oncology
  • Cell Biology
  • Developmental Biology

Background:

  • Tissue disorganization is an early indicator of cancer.
  • Dickkopf-3 (Dkk-3) is a Wnt signaling antagonist frequently lost in prostate cancer.
  • Dkk-3 is essential for maintaining prostate epithelial tissue architecture.

Purpose of the Study:

  • To investigate the role of Dkk-3 in prostate tissue organization and cell proliferation.
  • To elucidate the molecular mechanisms by which Dkk-3 regulates prostate structure.

Main Methods:

  • Comparison of Dkk3-null mice prostates with control littermates.
  • Analysis of three-dimensional prostate acini formed by human prostate epithelial cells with Dkk-3 silenced.
  • Assessment of TGF-β/Smad signaling pathways.

Main Results:

  • Dkk3-null mice exhibited increased prostate epithelial cell proliferation and altered tissue organization.
  • Silencing Dkk-3 in human prostate cells elevated proliferation and disrupted acinar structure.
  • Loss of Dkk-3 led to increased TGF-β/Smad signaling, which was reversed by pathway inhibitors.

Conclusions:

  • Dkk-3 plays a critical role in maintaining prostate structural integrity.
  • Dkk-3 limits TGF-β/Smad signaling to prevent excessive cell proliferation and maintain tissue organization.
  • Dkk-3 is a potential therapeutic target for prostate cancer.

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