Identification of a Novel MicroRNA Panel Associated with Metastasis Following Radical Prostatectomy for Prostate Cancer.

BACKGROUND/AIM: This is a case control study designed to identify one or more novel microRNA sequences associated with metastasis following radical prostatectomy for clinically localized prostate cancer. MATERIALS AND METHODS: Samples were obtained from patients with clinical evidence of metastatic disease following surgery (cases) and patients who showed no evidence of metastasis or biochemical recurrence at least 5 years following surgery (controls) as identified from a single-center, institutional database. Cases and controls were matched for tumor grade and duration of follow-up. RESULTS: Whole miRNome analysis identified 2,792 expressed miRNAs in 19 patient pairs. The 497 miRNA sequences with reads per million over 10, were used for analysis, bootstrapping with backward selection identified a panel of 5-miRNA (miR-17-3p, miR-27a-3p, miR-200a-3p, miR-375, and miR-376b-3p) with a risk score strongly associated with metastasis (AUC=89.5%, 95%CI=79.5-99.5%). Methodologically, most studies use the magnitude of differential expression with or without clinical judgement for selection of predictors for inclusion in panels. In order to strengthen the predictive model, a selection strategy was employed, bootstrapping with automated backwards selection, which relied on the strength of association for inclusion. CONCLUSION: A genome-wide analysis of microRNA expression identified a panel of 5 miRNAs strongly associated with prostate cancer metastasis following radical prostatectomy.