Introduction
Despite the widespread use of prostate specific antigen screening for early detection, prostate cancer remains the second leading cause of cancer related death among men in the US. Metastatic, hormone refractory prostate cancer (HRPCa) is the end stage, lethal form of the disease. Defining the molecular mechanisms underlying the transition of an androgen responsive prostate cancer represents an important clinical problem. Currently, no effective therapies exist for end stage, hormone refractory disease. In this study, we investigated the differentially expressed genes in primary prostate tumor vs. hormone refractory prostate tumor in order to identify potentially important therapeutic targets.