Characterization of plasma-derived and urinary exosomal microRNA from metastatic CRPC patients.

248 Background: Exosomes are nano-sized (50-100nm) vesicles derived from normal and tumor cells that function in cell-cell communication. These vesicles and their nucleic acid cargo may potentially serve as biomarkers for assessment of risk stratification and therapeutic response. The goal of this study was to characterize exosome derived microRNA (miRNA) isolated from plasma (pExos) and urine (uExos) of metastatic CRPC patients. Methods: Plasma samples were obtained from 18 mCRPC patients and 1 normal control. Following exosome isolation, RNA extraction and library prep, paired-end sequencing was performed using Illumina Hi-Seq 2000. A bioinformatics pipeline was used for data processing including alignment, duplicate removal, normalization, and variant calling. Visualization and differential analyses were performed with SNP & Variation Suite v8.x. RNA derived from uExos was amplified using whole transcriptome amplification and interrogated with Prostate Cancer (PCa) miScript miRNA PCR Array. Results: Ex...