Diagnostic, Prognostic and Theranostic Potential of miRNAs in Prostate Cancer

A novel class of gene regulators, small noncoding RNAs or microRNAs (miRNAs) has an important role in various malignancies, including prostate cancer (PCa). Contribution of dysregulated miRNAs in processes related to PCa malignant transformation and disease progression, especially androgen receptor signaling, proliferation, apoptosis, epithelial to mesenchymal transition and metastasis, is under extensive investigations. Thus, microRNAs emerge as potential noninvasive biomarkers that might have the potential in screening of PCa early stages, monitoring of patients at risk for metastases occurrence, as well as monitoring of therapeutic response and anticancer drug chemoresistance development. Being regarded as one of the PCa hallmarks, glutathione transferase P1 (GSTP1) expression seems as an important target both in PCa early detection and prognosis; therefore, miRNAs involved in regulation of GSTP1 expression probably play an important role in prostate carcinogenesis. Although certain limitations precede the development of novel biomarkers in PCa and replacement of the conventional ones, it is obvious that only by combining available diagnostic algorithms with novel multipanel tests and novel therapeutic possibilities, advances in personalized therapy and improvement of disease outcomes can be achieved in patients with prostate cancer. Application of miRNAs dominantly as possible predictive factors in chemoresistance development in PCa is highly anticipated.