Uncovering the expression patterns and the clinical significance of miR-182, miR-205, miR-27a and miR-369 in patients with urinary bladder cancer.

Background Given the high recurrence and progression rates and the absence of reliable markers for early detection andprognosis prediction of patients with urothelial bladder cancer (BCa), the exploration of new biomarkers with high specificityis imperative. Mainly, microRNAs (miRNAs), which are involved in the initiation and the progression of BCa. Herein, theexpression patterns of miR-182, miR-205, miR-27a and miR-369 were evaluated in patients with urothelial BCa.Methods and results The expression levels of the miRNAs were investigated in 90 FFPE tissue samples (23 LG NMIBC, 44HG NMIBC, 23 MIBC) and 10 non tumoral bladder tissues using TaqMan based RT-qPCR. Data analysis was performedusing 2-??CT method. Correlation to clinical characteristics of the patients was performed using descriptive statistics andthe receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic value of all miRNAs. MiR-27a,miR-205 and miR-369 were down-regulated whereas miR-182 was up-regulated in patients compared to controls (p < 0.001).MiR-205 and miR-182 positively segregate between NMIBC and MIBC (p = 0.002 and p = 0.000 respectively) whereas thedistribution of miR-27a's expression among these tumor groups was almost significant (p = 0.05) and that of miR-369'sexpression was irrelevant (p = 0.618). Interestingly, miR-182 was discriminative between LG NMIBC and HG NMIBC(p < 0.001) and Ta/T1 tumors (p = 0.000). Furthermore, high levels of miR-182 were potentially predictive of progressionin NMIBC patients (p = 0.01).Conclusion Collectively, a selection of miRNAs was found to be aberrantly expressed in BCa suggesting a potential diagnosticvalue in BCa. In addition, the clinical value of miR-182 and miR-205 as potential prognosis biomarkers was highlighted.Indeed, our data provide additional insights into cancer biology. Further functional or target studies are mandatoryto strengthen these findings.