• Register
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.


Leaving Community

Are you sure you want to leave this community? Leaving the community will revoke any permissions you have been granted in this community.


A dominant-negative mutant of androgen receptor coregulator ARA54 inhibits androgen receptor-mediated prostate cancer growth.

The ligand-bound androgen receptor (AR) regulates target genes via a mechanism involving coregulators such as androgen receptor-associated 54 (ARA54). We investigated whether the interruption of the AR coregulator function could lead to down-regulation of AR activity. Using in vitro mutagenesis and a yeast two-hybrid screening assay, we have isolated a mutant ARA54 (mt-ARA54) carrying a point mutation at amino acid 472 changing a glutamic acid to lysine, which acts as a dominant-negative inhibitor of AR transactivation. In transient transfection assays of prostate cancer cell lines, the mt-ARA54 suppressed endogenous mutated AR-mediated and exogenous wild-type AR-mediated transactivation in LNCaP and PC-3 cells, respectively. In DU145 cells, the mt-ARA54 suppressed exogenous ARA54 but not other coregulators, such as ARA55-enhanced or SRC-1-enhanced AR transactivation. In the LNCaP cells stably transfected with the plasmids encoding the mt-ARA54 under the doxycycline inducible system, the overexpression of the mt-ARA54 inhibited cell growth and endogenous expression of prostate-specific antigen. Mammalian two-hybrid assays further demonstrated that the mt-ARA54 can disrupt the interaction between wild-type ARA54 molecules, suggesting that ARA54 dimerization or oligomerization may play an essential role in the enhancement of AR transactivation. Together, our results demonstrate that a dominant-negative AR coregulator can suppress AR transactivation and cell proliferation in prostate cancer cells. Further studies may provide a new therapeutic approach for blocking AR-mediated prostate cancer growth.

Pubmed ID: 11673464


  • Miyamoto H
  • Rahman M
  • Takatera H
  • Kang HY
  • Yeh S
  • Chang HC
  • Nishimura K
  • Fujimoto N
  • Chang C


The Journal of biological chemistry

Publication Data

February 15, 2002

Associated Grants

  • Agency: NCI NIH HHS, Id: CA71570

Mesh Terms

  • Blotting, Western
  • Carrier Proteins
  • Down-Regulation
  • Genes, Dominant
  • Genes, Reporter
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Ligands
  • Lysine
  • Male
  • Models, Biological
  • Mutation
  • Plasmids
  • Point Mutation
  • Prostatic Neoplasms
  • Protein Binding
  • Protein Structure, Tertiary
  • Time Factors
  • Transcription, Genetic
  • Transcriptional Activation
  • Transfection
  • Tumor Cells, Cultured
  • Two-Hybrid System Techniques