The CPDR BRL will perform analytical validation of biomarkers and biomarker assays developed by other EDRN investigators and by other investigators. This includes Mass Spectrometry-based Detection of Multiple Candidate Biomarkers from Target Cells Enriched by Laser Capture Microdissection; Validation of Prostate Cancer Biomarkers Using the CPDR ERG Monoclonal Antibody (CPDR ERG-MAb) as a Paradigm; and Development and Testing of New Monoclonal Antibodies for Prostate Cancer Diagnosis and Prognosis Focusing on ETS family of oncoproteins and new prostate cancer markers.