Carcinogenesis investigation

Selikoff, I. J. (1977). Air Polution and Asbestos Carcinogenesis Investigation of Possible Synergism, WHO/IARC Pub. No. 16. World Health Organization International Agency for Research on Cancer Lyon, France. 

Fiber was shown to inhibit carcinogenicity of 2-acetylaminofluorene more than thirty years ago (7,17). A recent review (18) has pointed out the lack of consistency in studies of fiber effects on experimental colon carcinogenesis. Investigators use different strains of rat, stock or semipurified diets, and different carcinogens administered orally, subcutaneously or intrarec-tally (Table v). Ward et al. (19) found cellulose to have no effect on the carcinogenicity of azoxymethane (AOM) in male Fisher rats fed a semipurified diet. Freeman et al. (20), on the other hand, found cellulose to protect male Wistar rats from colon cancer induced by subcutaneous injection of 1,2-dimethylhydrazine (DMH). 

Hard, G. C. (1998). Recent developments in the investigation of thyroid regulation and thyroid carcinogenesis. Environ. Health Terspcct. 106(8), 427-4.36. 

The symposium upon which this book is based brought together leading investigators concerned with the mechanisms of carcinogenesis of PAH at the molecular level. The individual chapters in this book are not merely verbatim reports of the symposium proceedings but rather critical reviews of symposium topics with extensive references to investigations in other laboratories. Since the pertinent literature references are scattered in journals... 

This book is expected to be of interest to investigators active in all aspects of carcinogenesis research as well as to graduate students, educators, and others seeking an introduction to this important field of research. 

Recent advances in PAH carcinogenesis research over the past decade have led to identification of diol epoxide metabolites as the principal active forms of the PAH investigated to date Q,2). Benzo-(a)pyrene (BP) has been most intensively investigated, and it has been demonstrated that a diol epoxide metabolite anti-BPDE is the active intermediate which binds covalently to DNA in human and other mammalian tissues 0,4). Anti-BPDE was also demonstrated to be a powerful mutagen in both bacterial and mammalian cells (15) These findings stimulated an outpouring of research directed towards elucidation of the molecular mechanism of PAH carcinogenesis. 

Historically the process of activation has almost exclusively been studied by metabolizing compounds with liver preparations, leading most investigators in chemical carcinogenesis to think that... 

Although aminoacyl-tRNA synthetases are necessary for protein synthesis in all tissues, their importance in chemical carcinogenesis is difficult to assess. Mutation induction by this pathway has been studied extensively (123), yet metabolic activation in a carcinogen-target tissue has not been demonstrated. The only exception is hepatic prolyl-tRNA synthetase activation of N-hydroxy-Trp-P-2 however, hepatic O-acetylation of this substrate also occurs to an appreciable extent (12). Further investigations involving the use of specific enzyme inhibitors would be helpful in addressing this problem. 

Such reactions have only been investigated on their role in the processes of ageing and carcinogenesis to a large extent (Dizdaroglu 1991), their effects on environmental contaminants and organisms have not been fully realized. Because of the short time and difficulties in chemical analyses for transitory presence of free radicals, relationship between free radical concentrations and effects on pollutants or natural microorganisms has not been fully established. It is clear that further... 

Van Beneden, R.J., Environmental effects and aquatic organisms investigations of molecular mechanisms of carcinogenesis, Em. Health Perspect., 105 (Suppl. 3), 669, 1997. 

Mackay JM, Fox V, Griffiths K, et al Trichloroacetic acid Investigation into the mechanism of chromosomal damage in the in vitro human lymphocyte cytogenetic assay and the mouse bone marrow micronucleus test. Carcinogenesis 16(5) 1127-1133, 1995... 

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