Cancer chemical carcinogenesis

Experimental animal studies have played a key role in the understanding of the mechanisms of chemical carcinogenesis. The duration of development of a cancer in humans may be several decades, and the development probably includes several steps. Furthermore, individual susceptibility is also important for the disease. Therefore, it has been extremely difficult to make the required observations in exposed individuals. 

Chemical Carcinogenesis Program, Frederick Cancer Research Center, Frederick, MD 21701... 

Pryor, W.A. (1987). Cigarette smoke and the involvement of free radical reactions in chemical carcinogenesis. Br. J. Cancer 55, 19-23. 

Clearly, in many cases, cancer is the result of the action of synthetic and naturally occurring chemical species. The role of chemicals in causing cancer is called chemical carcinogenesis. It is often regarded as the single most important facet of toxicology and clearly the one that receives the most publicity. 

It is not known how chemicals cause cancer. A fascinating aspect of the story is that many "carcinogenic" chemicals are in fact, not the culprits responsible for cancer induction. The metabolic processes of the body change the chemicals from relatively innocuous substances into reactive intermediates which in as yet unknown fashion, trigger the chain of events which finally result in tumor formation. In other words, chemical carcinogenesis is an effect of "failed" detoxification. 

Spamins, V.L., Venegas, P.L. Wattenberg, L.W. (1982) Glutathione S-transferase achvity enhancement by compormds inhibiting chemical carcinogenesis and by dietary conshtuents. J. natl Cancer Inst, 68, 493 96... 

Many experimental obs vations, some of which have predicted human cancer data, have been possible because of organ-specific animal models for chemical carcinogenesis. These models, being similar to thdr human counterparts, strengthen the association of environmental exposures with cancer development, and aid in the extrapolation of carcinogenesis data from animal species to humans. They also provide a valuable resource for studies of pathogenesis, risk-modifying factors, and cancer prevention. 

Katsuta, H. and Takaoka, T. (1975). Chemical carcinogenesis of mammalian epithelial cells in tissue culture, Cancer Res. 17,59. 

Richards, J., Guzman, R., Yang, J., Nandi, S., and Konrad, M. (1980). Chemical carcinogenesis of mammary epithelium in cell culture, page 467 in Cell Biology of Breast Cancer, McGrath, C.M., Brennan, M.J., and Rich, M.A., Eds. (Academic Press, New York). 

E. K. (1967). Host properties determine target, bladder or liver, in chemical carcinogenesis, page 45 in Bladder Cancer, Deichmann, W.B., Ed. (Aesculapius Publishing Co., Alabama). 

Woo, Y.-T. and Lai, D.Y., (2010) QSAR analysis of genotoxic and nongenotoxic carcinogens a state-of-the-art overview, in Cancer Risk Assessment Chemical Carcinogenesis from Biology to Standards Quantification (eds G. Hsu and T. Stedeford), John Wiley and Sons, Ltd., Hoboken, N.J., pp. 517-556. 

Miller, E.C. (1978) Some current perspectives on chemical carcinogenesis in humans and experimental animals Presidential Address. Cancer Res., 38, 1479-1496. 

Williams GM. Mechanisms of chemical carcinogenesis and applications to human cancer risk assessment. Toxicology 2001 166 3-10. 

Mankind is already exposed to many carcinogens whose presence in the environment cannot be easily controlled. In view of the nature of cancer, the long latent period of its development, and the irreversibility of chemical carcinogenesis, it would be highly improper to expose the general population to an increased risk if the benefits were small, questionable, or restricted to limited segments of the population. Such benefit-risk considerations not only must be based on scientific facts but also must be ethical, with as broad a population base as possible used in the decision-making process. 

Haddow, A. and G.A.R. Kon, p. 314 "Chemistry of Carcinogenic Compounds," in "Chemical Carcinogenesis," pp. 31 1-326, British Med. Bull. 4, nos. 5 6. paper 962 (19 +7) Excellent historical treatment of the role of chemistry in the study of cancer, with allusions to general toxicology, including birth defects. 

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