Overexpression of mir-20a-5p in tumor epithelium is an independent negative prognostic indicator in prostate cancer—a multi-institutional study

Abstract

<i>Objective</i>: assessing the prognostic role of miR-20a-5p, in terms of clinical outcome, in a large multi-institutional cohort study.<br><br>

<i>Methods</i>: Tissue microarrays from 535 patients’ prostatectomy specimens were constructed. In situ hybridization was performed to assess the expression level of miR-20a-5p in different tissue subregions: tumor stroma (TS) and tumor epithelium (TE). In vitro analysis was performed on prostate cancer cell lines.<br><br>

<i>Results</i>: A high miR-20a-5p expression was found negatively in association with biochemical failure in TE, TS and TE + TS (<i>p</i> = 0.001, <i>p</i> = 0.003 and <i>p</i> = 0.001, respectively). Multivariable analysis confirmed that high miR-20a-5p expression in TE independently predicts dismal prognosis for biochemical failure (HR = 1.56, 95% CI: 1.10–2.21, <i>p</i> = 0.014). Both DU145 and PC3 cells exhibited increased migration ability after transient overexpression of miR-20a-5p, as well as significant elevation of invasion in DU145 cells.<br><br>

<i>Conclusion</i>: A high miR-20a-5p expression in tumor epithelium is an independent negative predictor for biochemical prostate cancer recurrence.