Biochemical and nutritional toxicology, with an emphasis on cancer prevention, is the focus of our laboratory. Epidemiological studies show that a diet rich in cruciferous vegetables, such as broccoli and Brussels sprouts, can lower the incidence of several cancers, including liver, prostate and colorectal. Our experiments identify how components in crucifers alter the synthesis of detoxification enzymes, resulting in more rapid clearance of deleterious compounds from the body before they can initiate a toxic or carcinogenic response. A major goal is to develop cruciferous vegetables with increased concentrations of chemopreventive agents and we work closely with an interdisciplinary group of 5 faculty to meet this goal. Experiments probing the mechanism of upregulation of detoxification enzymes apply molecular biology and biochemical enzyme assays to human and rodent liver cells in culture. Immunohistochemical and enzyme assay studies using purified chemicals or the whole vegetable fed to rodents confirm the findings from in vitro experiments. We have identified a synergism between two of the more abundant bioactive components in crucifers. The importance of this finding is two-fold: first that smaller doses of the vegetable should provide protection; and second that supplements containing the optimal mixture for protection could be formulated for individuals at high risk for cancer. These studies are being expanded to prostate, since prostate cancer is presently the most common cancer, with the second highest number of mortalities of any cancer, within the U.S. Functional foods; prevention of cancer through diet; role of detoxification enzymes in protection from cancer and toxicity.