title: High throughput microscopy identifies bisphenol AP, a bisphenol A analog, as a novel AR down-regulator.
abstract: Prostate cancer remains a deadly disease especially when patients become resistant to drugs that target the Androgen Receptor (AR) ligand binding domain. At this stage, patients develop recurring castrate-resistant prostate cancers (CRPCs). Interestingly, CRPC tumors maintain dependency on AR for growth; moreover, in CRPCs, constitutively active AR splice variants (e.g., AR-V7) begin to be expressed at higher levels. These splice variants lack the ligand binding domain and are rendered insensitive to current endocrine therapies. Thus, it is of paramount importance to understand what regulates the expression of AR and its splice variants to identify new therapeutic strategies in CRPCs. Here, we used high throughput microscopy and quantitative image analysis to evaluate effects of selected endocrine disruptors on AR levels in multiple breast and prostate cancer cell lines. Bisphenol AP (BPAP), which is used in chemical and medical industries, was identified as a down-regulator of both full length AR and the AR-V7 splice variant. We validated its activity by performing time-course, dose-response, Western blot and qPCR analyses. BPAP also reduced the percent of cells in S phase, which was accompanied by a ~60% loss in cell numbers and colony formation in anchorage-independent growth assays. Moreover, it affected mitochondria size and cell metabolism. In conclusion, our high content analysis-based screening platform was used to classify the effect of compounds on endogenous ARs, and identified BPAP as being capable of causing AR (both full-length and variants) down-regulation, cell cycle arrest and metabolic alterations in CRPC cell lines.
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Fabio
authors.initials: F
authors.lastname: Stossi
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Radhika D
authors.initials: RD
authors.lastname: Dandekar
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bolt
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Justin Y
authors.initials: JY
authors.lastname: Newberg
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Maureen G
authors.initials: MG
authors.lastname: Mancini
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Akash K
authors.initials: AK
authors.lastname: Kaushik
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Vasanta
authors.initials: V
authors.lastname: Putluri
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Arun
authors.initials: A
authors.lastname: Sreekumar
authors.affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Mancini
mesh_terms: D059002:Androgen Receptor Antagonists / Q000494:pharmacology*; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D045744:Cell Line, Tumor; D015536:Down-Regulation; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D057166:High-Throughput Screening Assays / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008853:Microscopy / Q000379:methods; D011108:Polymers / Q000494:pharmacology*; D064129:Prostatic Neoplasms, Castration-Resistant; D011944:Receptors, Androgen / Q000187:drug effects; D059010:Single-Cell Analysis; D000098826:Bisphenol A Compounds; D000098827:Polycarbonates
chemical_list: D059002:Androgen Receptor Antagonists; D001559:Benzhydryl Compounds; D011108:Polymers; D011944:Receptors, Androgen; C028237:bisphenol-A-polycarbonate; D000098826:Bisphenol A Compounds; D000098827:Polycarbonates
keywords: AR-V7; androgen receptor; bisphenol A analogs; castrate resistant prostate cancer; high throughput microscopy