Delbert M. Shankel Departments of }1icrobiology and Biochemistry The University of Kansas Lawrence, Kansas 66045 Welcome to the "International Conference on Mecha. nisms of Antimutagen esis and Anticarcinogenesis. " We are delighted that so many of you have chosen to attend this first meeting on this important topic. The significance of genetic changes in cells has been recognized for many years. The seminal observations of Henri in 1914 (UV), Muller in 1927 (X-rays), and Auerbach in 1946 (chemical agents) established the fact that physical and chemical agents which may be present in our environment are capable of producing profound changes in heredity. It is now well-estab lished, of course, that such changes can result in the development of can cer, produce hereditary birth defects, alter microorganisms to cause drug resistance, or other harmful (or even beneficial) changes; it is likely that the processes of mutagenesis and the intricate balance between muta genesis and antimutagenesis are involved in aging, evolution, and other fundamental life processe8. Consequently, we hope and believe that assem bling thi. s group of scientists to share current fundamental and applied research in these areas will lead to a better understanding of these proc esses and to long-term benefits for society. As stated clearly by Garfield (4), "Almost every aspect of modern liv ing exposes us to health risks.

Inhalt
Keynote Address.- Carcinogens and Anticarcinogens.- Activation and Inactivation of Mutagens and Carcinogens Part I.- The Relation of Activation and Inactivation to Antimutagenic Processes.- Cancer and Free Radicals.- Cytochromes P-450 and the Activation and Inactivation of Mutagens and Carcinogens.- Alteration of Mutagenic Potentials by Peroxidase, Catalase, and Superoxide Dismutase.- Activation and Inactivation of Mutagens and Carcinogens Part II.- Effects of Vitamins C and E on Carcinogen Formation and Action, and Relationship to Human Cancer.- Modifiers of Endogenous Nitrosamine Synthesis and Metabolism.- Glutathione Transferases and Carcinogenesis.- Natural Environmental Antimutagens.- Introduction: Natural Environmental Antimutagens.- Antioxidants/Antimutagens in Foods.- Role of Enzymes in Antimutagenes is of Human Saliva and Serum.- Isolation and Identification of Higher Plant Agents Active in Antimutagenic Assay Systems: Glycyrrhiza glabra.- Mechanism of Action of Antimutagens and Anticarcinogens.- Interception of Toxic Agents/Mutagens/Carcinogens: Some of Nature's Novel Strategies.- Antimutagens and Their Modes of Action.- Avoidance of Errors in Dna.- Introduction: Avoidance of Spontaneously Occurring Errors in DNA.- Introduction: Avoidance of Errors After DNA Damage.- Alkylation and Oxidative Damages to DNA: Constitutive and Inducible Repair Systems.- Molecular Mechanism of Adaptive Response to Alkylating Agents.- Nucleotide Excision Repair Genes from the Yeast Saccharomyces cerevisiae.- The Fixation of Errors.- Introduction: Molecular Basis of Genomic Stability and Change.- Genetic Analyses of the Roles of UmuDC and MucAB in Mutagenesis.- Mechanisms of Spontaneous Mutagenesis: Clues from Altered Mutational Specificity in DNA Repair-DefectiveStrains.- Genetics and Molecular Biology of Mammalian Cells Part I.- Introduction: Comparative Responses to DNA Damage in Bacteria and Mammalian Cells.- Inducible Cellular Responses to DNA Damage in Mammalian Cells.- Single-Base Mutations Associated with Mouse Lymphomas.- The Mouse Mutant Wasted: An Animal Model for Ataxia-Telangiectasia.- Genetics and Molecular Biology of Mammalian Cells Part II.- Introduction: Oxygen Metabolism, DNA Repair, and the Origin of Spontaneous Genetic Instability.- Multiple Inducible Cytochromes P-450 in Yeast.- DNA Repair Genes of Mammalian Cells.- Genetic and Chemical Factors Affecting Chemical Mutagenesis in Cultured Mammalian Cells.- Mechanisms of Carcinogenicity and AnticarcinogenicityPart I.- Mechanisms of Carcinogenicity and Anticarcinogenicity: Role of Dietary Components.- Reducing the Genotoxic Damage in the Oral Mucosa of Betel Quid/Tobacco Chewers.- The Concentration of Bile Acids in the Fecal Stream as a Risk Factor for Colon Cancer.- Hormones and Dietary Factors Controlling Gene Activation and Expression in Carcinogenesis.- Dietary Promoters and Antipromoters.- Mechanisms of Carcinogenicity and Anticarcinogenicity Part II.- A Mutagen Is a Mutagen, Not Necessarily a Carcinogen.- DNA Repair and Replication in Xeroderma Pigmentosum and Related Disorders.- Role of Intercellular Communication in Modifying the Consequences of Mutations in Somatic Cells.- Mechanisms of Carcinogenicity and Anticarcinogenicity Part III.- Genetic Aspects of Cancer Epidemiology.- Protective Effects of Beta-Carotene Against Psoralen Phototoxicity: Relevance to Protection Against Carcinogenesis.- Anticarcinogenic and Other Protective Effects of Dithiolthiones.- Antioxidants as Antitumor Promoters.- Future Directions forResearch in Antimutagenesis and Anticarcinogenesis.- Introduction: Future Directions for Research in Antimutagenesis and Anticarcinogenesis.- Inhibitors of Mutagenesis and Their Relevance to Carcinogenesis.- Population Consequences of Mutagenesis and Antimutagenesis.- A SummaryAnd a Look Ahead.- Poster Abstracts.- Organizing Committee.