**1. Introduction**

Although significant progress in the investigation of prostate cancer biomarkers, some men are overdiagnosed with indolent prostate cancer while others die from aggressive disease diagnosed too late. The introduction of PSA (Prostate Specific Antigen) in clinical practice has resulted in early detection and reduced mortality from prostate cancer (Schroder et al., 2009). Despite its great utility for prostate cancer detection and prognostication, PSA as a single test has several limitations. Prostate cancer screening remains thus controversial, because of the risk of overdiagnosis reduced mortality and overtreatment and the inability to detect a significant proportion of aggressive tumors. To extend the limited information provided by PSA testing, other biomarkers that could discriminate between indolent from aggressive cancers are therefore an absolute must. Despite numerous studies of biomarker candidates have been presented the last decade, the identification of the most aggressive subsets of this disease is still not possible. This review will cover last years development in this area and highlight the most promising biomarkers in prostate cancer, which have been divided into three groups; protein-based, DNA-based and RNA-based markers.
