IntroductionProstate cancer (PCa) is one of the most common cancers worldwide. PCa diagnosis is mostly based on solid biopsy and prostate-specific antigen (PSA), which have the disadvantages of being invasive and insensitive, respectively. Recently, the detection of microRNAs (miRNAs) in expressed prostatic secretions (EPS) has been a promising approach for PCa diagnosis. The aim of this study is to quantify transcriptional levels of miRNA-32 in the urine of prostate cancer patients. Materials and methodsIn this study, we evaluated the expression of miRNA-32 in the urine of 27 PCa patients, 48 benign prostatic hyperplasia (BPH) and 20 healthy controls, using quantitative real-time PCR (qPCR). The expression levels were then compared with the clinicopathological characteristics of patients. ResultsThe expression level of miRNA-32 in PCa patients was significantly higher than the control group (P < 0.01) and BPH cases (P < 0.01), and was associated with advanced tumor stage (P < 0.05). In addition, the expression of miRNA-32 had significant correlation with patients’ age (r = 0.39, P = 0.043). Area under ROC curve (AUC) for the discrimination of PCa samples from control and BPH samples were 0.93 (P < 0.0001) and 0.78 (P < 0.0001), respectively. We also used logistic regression analysis to integrate the results of PSA, prostate volume and miRNA-32, and presented a predictive model for distinguishing PCa from BPH, highlighting the clinical utility of miRNA-32 in cancer diagnosis and risk assessment. ConclusionsMeasurement of miRNA-32 expression in urine may have significance for the detection of PCa. Inclusion of miRNA-32 in logistic regression along with PSA and prostate volume increases the accuracy of cancer diagnosis. MicroAbstractPCa diagnosis is mostly based on solid biopsy and prostate-specific antigen (PSA), which have disadvantages of being invasive and insensitive, respectively. Despite the huge advances that have been made in the diagnosis of PCa, more than 21% of PCa patients are diagnosed when the tumor has spread locally or metastasized to distant organs. These patients have a lower 5-year overall survival. In this study, we evaluated the expression of miRNA-32 in the urine of 27 PCa patients, 48 benign prostatic hyperplasia (BPH) patients before surgery for sampling, and 20 healthy subjects using quantitative and real-time PCR. Then the expression level was compared with the clinicopathological characteristics of the patients. We investigated the expression level of miRNA-32 in urine as a non-invasive approach for the first time to diagnose PCa cancer. Our results showed that urinary miRNA-32 levels are higher in PCa patients than in BPH and are associated with advanced disease. Our data and ROC curve analysis show that miRNA-32 expression level has acceptable sensitivity and specificity and higher positive predictive value for the diagnosis of PCa and can be used together with other biomarkers, especially PS