Oncogene miR-187-5p is associated with cellular proliferation, migration, invasion, apoptosis and an increased risk of recurrence in bladder cancer

Background: Bladder cancer, the ninth-most-common malignancy worldwide with an estimated 356,000 new cases and 145,000 deaths annually, has a propensity to relapse, requiring lifelong monitoring after diagnosis. 75% patients diagnosed with BC are non-muscle invasive BC and over 50% of them experience recurrences within 6-12 years of initial diagnosis. miRNA are small, noncoding RNA and shown to be oncogenes or antioncogenes in bladder cancer, contributing to numerous BC cell processes, including cell proliferation, differentiation, migration and apoptosis. Methods: RT-qPCR were performed to detect the expression of miR-187-5p in tissues and cell lines, After which, clinicopathological variables and the prognostic value of altered miR-187-5p expression in BC was analyzed with the 48 formalin-fixed paraffin-embedded BC samples. Moreover, Cell functional assays (wound healing assay, CCK-8 assay, transwell assay and flow cytometry assay) were performed to explore the relationship between miR-187-5p expression and cell proliferation, migration, invasion and apoptosis in BC. Results: Up-regulation of miR-187-5p was observed in BC tissues and BC cell lines. Cox proportional hazard regression analysis demonstrated that the patients with low expression of miR-187-5p experience lower risks of recurrence in the univariate and multivariate analysis. The Kaplan-Meier recurrence-free curves suggested that the patients with low expression of miR-187-5p experience lower risks of recurrence. Up-regulation of miR-187-5p promotes cell proliferation and mobility and inhibits the apoptosis of 5637 and UM-UC-3 cell, while downregulation of miR-187-5p reverses these effects. Conclusions: The results of our study demonstrated that oncogene miR-187-5p is associated with cellular proliferation, migration, invasion, apoptosis and an increased risk of recurrence in bladder cancer.