Quantitative Investigation of Microrna-32 in the Urine of Prostate Cancer Patients and Its Relationship with Clinicopathological Characteristics

Introduction Prostate 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 methods In 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. Results The 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. Conclusions Measurement 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. MicroAbstract PCa 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