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A novel function of caspase-8 in the regulation of androgen-receptor-driven gene expression

Wei Qi1, Hong Wu, Lin Yang

  • 1Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.

The EMBO Journal
|December 16, 2006
PubMed

Insights

Caspase-8 (Casp8) inhibits androgen receptor (AR) activity, impacting male development and prostate cancer. This study reveals Casp8

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Endocrinology

Background:

  • Androgen receptor (AR) transcriptional regulation is vital for male sexual development and prostate cancer progression.
  • Identifying novel regulators of AR activity is crucial for understanding these processes.

Purpose of the Study:

  • To identify molecules that regulate androgen receptor (AR)-driven transcription using expression cloning.
  • To elucidate the novel function of caspase-8 (Casp8) in AR transcriptional regulation.

Main Methods:

  • Expression cloning strategy using a human cDNA library.
  • Protein-protein interaction analysis to identify binding motifs.
  • RNA interference (RNAi) for gene knockdown studies in LNCaP cells.

Main Results:

  • Caspase-8 (Casp8) was identified as a regulator of AR-dependent transcription.
  • Casp8 repressed AR activity independently of its apoptotic function by disrupting AR amino-terminal and carboxy-terminal (N/C) interaction.
  • Casp8 inhibited androgen-induced AR nuclear localization and affected AR-targeting gene expression.

Conclusions:

  • Caspase-8 (Casp8) possesses a novel function in repressing androgen receptor (AR) transcriptional activity.
  • This function is independent of Casp8's role in apoptosis and involves direct interaction with the AR.
  • Casp8 represents a new target for therapeutic intervention in AR-dependent diseases like prostate cancer.

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