This is a comprehensive reference survey on the identification and development of promising cancer chemopreventive agents that will help stimulate further novel research and new approvable drugs. For each agent, the authors review the relevant mechanisms of action, the criteria for populations benefiting from intervention, the safety and pharmacodynamics, clinical study design emphasizing the use of precancers, and early associated cellular and molecular biomarkers of carcinogenesis. The pharmacologic and/or mechanistic classes discussed range from antimutagens, antiinflammatories, and the nuclear receptor superfamily, to signal transduction modulators, antioxidants, vitamins, and minerals. The overall focus is on molecular targets and mechanisms. A second volume, "Strategies in Chemoprevention", describes the exciting methodologies that will accelerate progress in this field and discusses the state of clinical development of chemoprevention in the various human cancer target organs.