Evaluating the Urinary Exosome MicroRNA Profile in Prostate Cancer

Background/Objectives: Prostate cancer is the second most frequent cancer among men and the 5th leading cause of cancer death among men worldwide. Identification of urine-derived biomarkers, such as exosomal miRNAs, in liquid biopsies for prostate cancer could be very beneficial for screening and active surveillance. Methods: Urine was collected from 42 patients with biopsy-proven evidence of prostate cancer and exosomes were extracted. Transcriptomic analysis was performed on the urine-derived exosomal miRNA and compared to the urine-derived exosomal miRNA profiles from 10 normal control donors and 15 von Hippel-Lindau (VHL) syndrome patients with clear cell renal cell carcinoma (ccRCC). Results: Urine-derived exosomal miRNA profiles of prostate patients were significantly different from normal control individuals. Significantly increased expression of miR-122-5p and decreased expression of miR-125-5p and miR-16-5p were observed in the urine-derived exosomes from prostate cancer patients. Significant upregulation of miR-30a-5p and downregulation of miR-320-5p, miR-320b, and miR-320c were observed in the urine-derived exosomes from both prostate cancer patients and VHL patients with ccRCC, indicating these miRNAs could be non-specific markers of urological cancer. Increased expression of miR-10a-5p and miR-30e-5p or miR-532-5p and miR-206 correlated with the presence of either extracapsular or perineural invasion, respectively. Conclusions: This study highlights the potential for urine-derived exosomal miRNA profiles to identify the presence of prostate cancer and predict clinical features, additionally showing that miRNA signals could be non-specific markers of urologic cancer types. Further validation studies are necessary to demonstrate the utility of urine-derived exosomal miRNA profiles as biomarkers for diagnosis or prognosis in prostate cancer.