ObjectiveTo detect the expression levels of microRNA-186(miR-186) in the peripheral blood of patients with idiopathic azoospermia(IA), and investiagte its diagnostic value for IA.

MethodsThe peripheral blood samples from 140 IA patients from 2015 to 2017 in urology department and 140 normal fertile men were divided into the IA group and control group, respectively.The DNA and RNA in two groups were routinely extracted from peripheral blood, and the microdeletion of azoospermia factor(AZF) in two groups were detected using multiplex PCR.The expression levels of miR-186 in two groups were detected using quantitative real-time PCR.The correlation between miR-186 expression and AZF microdeletion in peripheral blood was analyzed.The diagnostic value of miR-186 for IA in peripheral blood was evaluated by ROC analysis.

ResultsThe differences of the age, body mass index, testosterone level and smoking status were not statistically significant between two groups(P>0.05).Eight patients with AZF microdeletion in the IA group were found, and the microdeletion rate of which was 5.71%(8/140), while no AZF microdeletion was detected in the control group(P>0.05).The expression level of miR-186 in IA group was significantly higher than that in control group(P < 0.01).The miR-186 expression in peripheral blood was not correlated with AZF microdeletion(P>0.05).The miR-186 had a higher diagnosis value for IA, and the area under the ROC curve was 0.84(95% CI: 0.79 to 0.87).The expression level of miR-186 at 0.52 was the best diagnostic cut-off point, and the sensitivity and specificity were 71.86% and 80.39%, respectively.

ConclusionsThe expression level of miR-186 is high in the peripheral blood of IA patients, but its expression is not correlated with AZF microdeletion.High expression of miR-186 in peripheral blood may serve as a new diagnostic biomarker for IA.