title: Targeting androgen receptor and JunD interaction for prevention of prostate cancer progression.
abstract: BACKGROUND
  Multiple studies show that reactive oxygen species (ROS) play a major role in prostate cancer (PCa) development and progression. Previously, we reported an induction of Spermidine/Spermine N(1) -Acetyl Transferase (SSAT) by androgen-activated androgen receptor (AR)-JunD protein complex that leads to over-production of ROS in PCa cells. In our current research, we identify small molecules that specifically block AR-JunD in this ROS-generating metabolic pathway.
  
  
  METHODS
  A high throughput assay based on Gaussia Luciferase reconstitution was used to identify inhibitors of the AR-JunD interaction. Selected hits were further screened using a fluorescence polarization competitor assay to eliminate those that bind to the AR Ligand Binding Domain (LBD), in order to identify molecules that specifically target events downstream to androgen activation of AR. Eleven molecules were selected for studies on their efficacy against ROS generation and growth of cultured human PCa cells by DCFH dye-oxidation assay and DNA fluorescence assay, respectively. In situ Proximity Ligation Assay (PLA), SSAT promoter-luciferase reporter assay, and western blotting of apoptosis and cell cycle markers were used to study mechanism of action of the lead compound.
  
  
  RESULTS
  Selected lead compound GWARJD10 with EC(50) 10 μM against ROS production was shown to block AR-JunD interaction in situ as well as block androgen-induced SSAT gene expression at IC(50) 5 μM. This compound had no effect on apoptosis markers, but reduced cyclin D1 protein level.
  
  
  CONCLUSIONS
  Inhibitor of AR-JunD interaction, GWARJD10 shows promise for prevention of progression of PCa at an early stage of the disease by blocking growth and ROS production.
authors.affiliation: University of Wisconsin Carbone Cancer Center, Madison, Wisconsin.
authors.forename: Farideh
authors.initials: F
authors.lastname: Mehraein-Ghomi
authors.forename: Stacy J
authors.initials: SJ
authors.lastname: Kegel
authors.forename: Dawn R
authors.initials: DR
authors.lastname: Church
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Schmidt
authors.forename: Quentin R
authors.initials: QR
authors.lastname: Reuter
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Saphner
authors.forename: Hirak S
authors.initials: HS
authors.lastname: Basu
authors.forename: George
authors.initials: G
authors.lastname: Wilding
mesh_terms: D017209:Apoptosis / Q000235:genetics; D045744:Cell Line, Tumor; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D018450:Disease Progression; D006801:Humans; D008297:Male; D011467:Prostate / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*
chemical_list: C559371:JunD protein, human; D016755:Proto-Oncogene Proteins c-jun; D017382:Reactive Oxygen Species; D011944:Receptors, Androgen; D019938:Cyclin D1
keywords: AR-JunD protein-protein interaction; cellular reactive oxygen species; cyclin D1; small molecule inhibitors