Abstract 4449: Effects of endocrine therapy on mRNA- and microRNA expression profiles in prostate cancer

Introduction & Objectives: The gold standard treatment for advanced prostate cancer is endocrine therapy either by castration (surgical or chemical) or with antiandrogens. Although endocrine therapy has been used for decades, the molecular consequences of androgen deprivation are poorly understood. The aim of this study was to investigate how endocrine therapy affects genome-wide gene expression and to ascertain whether chemical castration or antiandrogen use leads to unique gene expression profiles. Methods: 30 patients were randomized equally into three groups: no treatment, bicalutamide (antiandrogen) 150 mg daily, and goserelin (GnRH agonist) 3.6 mg every 4 weeks. Following the neoadjuvant treatment for 12 weeks, patients underwent radical prostatectomy. Freshly frozen specimens were collected for expression profiling of both protein (mRNA) and microRNA (miRNAs) coding genes using Illumina (probes for ∼25 000 mRNAs) and Agilent (723 miRNAs) microarrays, respectively. The amount of cancer, benign epithelium, and stroma in the specimens was assessed using HE 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4449.