Prostate cancer detection using a noninvasive method for quantifying miRNAs

Cancer is one of the diseases with more incidence in industrialized countries. Early detection is important for patient survival in terms of treatment and clinical decisions. Several methods have been described to improve detection, diagnostic, and treatment in cancer, but the diagnostic methods are very aggressive for patients. Biopsies have been the gold standard to determine the clinical pathological characteristics of cancer tissues for many years. The biopsies procedure is very uncomfortable for the patients, and in many cases the results are negative to cancer. Therefore, patients are submitted to a second round of biopsies, because their clinical conditions implicate the presence of neoplasia. During the last years, noninvasive methods have shown relevance because they could be good indicators for cancer detection at molecular level. Molecular signatures have been included to characterize different stages of the disease, and thereby the objective is to prevent unnecessary biopsies. Several body fluids as urine, serum, blood, semen, saliva, etc. have been used. In fluids, miRNA detection provides a promising tool to obtain molecular signatures for different types of cancer. Urine represents a very good option to find molecules representative of tumor status in prostate cancer. The presence or the absence of miRNA involved in the development of the disease has been demonstrated. In this chapter we describe a method to quantify mature miRNA signatures using a noninvasive test using a body fluid such as urine.