Human seminal fluid as a source of prostate cancer-specific microRNA biomarkers

Human seminal fluid as a source of prostate cancer-specific microRNA biomarkers Dear Editor, Prostate cancer (PCa) is the most commonly diagnosed malignancy among men living in Western countries and a major cause of cancer-related deaths.Biopsy-based diagnosis of PCa is usually performed following an elevated serum prostate-specific antigen (PSA) measurement and/or abnormal digital rectal examination (DRE).The deficiencies of serum PSA as a biomarker have been well documented (Roobol & Carlsson 2013).While it is highly specific for tissues of prostatic origin, PSA is not cancer specific, resulting in many unnecessary biopsies of benign disease.Moreover, PSA screening has resulted in substantial over-diagnosis and over-treatment of indolent tumours without having a significant effect on PCa mortality (Schroder et al. 2009).Biomarkers that could identify patients with clinically significant PCa would be ideal but are currently lacking.Aberrant microRNA (miRNA) expression is a common feature of many diseases, including PCa (Selth et al. 2012), and there has been widespread interest in the diagnostic, prognostic and predictive potential of these molecules.Recent focus has shifted towards circulating miRNAs, which can be sourced from minimally invasive samples, such as serum, plasma and urine, and show promise as a Mann-Whitney U test or Fisher's exact test, P value.