Prostate cancer is the most commonly diagnosed malignancy in men in the United States, although our understanding of the molecular basis for this disease remains incomplete. We are interested in characterizing consistent alterations in the structure and expression of the genome of human prostate cancer cells as a means of identifying genes critical in the pathways of prostatic carcinogenesis. We are focusing on somatic genomic alterations occurring in sporadic prostate cancers, as well as germline variations which confer increases in prostate cancer risk. Both genome wide and candidate gene approaches are being pursued, and cancer associated changes in gene expression analyses of normal and malignant prostate cells are being cataloged as a complementary approach in these efforts. It is anticipated that this work will assist in providing more effective methodologies to identify men at high risk for this disease, in general, and in particular, to identify new markers of prognostic and therapeutic significance that could lead to more effective management of this common disease.