Book excerpt: Our specific aims are to examine men with prostate cancer from 4 different racial-ethnic groups to determine the prevalence of molecular and cellular changes that may play a role in prostate tumor progression, particularly invasion and metastasis. We are currently assessing tissue samples from patients with prostate cancer for markers involved in the following pathways: a) hormonal regulation and responsiveness, b) cell cycle regulation c) tumor angiogenesis and its regulators and d) invasion and metastasis. When our tissue analysis is completed we will determine the relationship between the changes in these key biological pathways and race/ethnicity, age and the intermediate markers of disease progression (i.e. tumor grade and stage) Finally, these molecular and cellular changes will be related to clinical outcome (i.e survival and mortality) within and between racial/ethnic groups.