Gene activation / signal transduction mechanisms by natural cancer chemopreventive compounds, anti-cancer drugs, and environmental pollutants; molecular biology of drug metabolizing enzymes and drug transporters; pharmacokinetics, pharmacodynamics, and drug metabolism of biotechnology products, natural cancer chemopreventive compounds, anti-cancer drugs, and environmental pollutants; drug metabolism studies using cell lines expressing different drug metabolizing enzymes; and chemoprevention of colon and prostate cancers