Cocarcinogenicity mechanisms

Finally, it is important that further research be carried out on the identification and mechanism of action of environmental cocarcinogens and tumor promoters which can enhance the carcinogenicity of PAH. Human exposure to at least trace amounts of PAH is unavoidable. The probability of eventual tumor development may be controlled primarily by repeated exposure to cocarcinogens or promoters. 

It is postulated from epidemiologic studies that fibrous materials are also carcinogenic or cocarcinogenic. Lung cancer and mesothelioma (cancer of the pleura) have both been linked to occupational exposure of fibrous materials. The mechanisms of induction of these, as most cancers, are thought to start as changes in the affected cells. 

Epigenetic carcinogens cause the appearance of tumors without a genotoxic effect. This includes promotion, immunosuppression, cocarcinogenicity, and cytotoxicity. This group probably involves diverse mechanisms. They may act by... 

Van Duuren, B.L., G. Witz, and B.M. Goldschmitt Structure-activity relationships of tumor promoters and cocarcinogens and interaction of phorbol myristate acetate and related esters with plasma membranes in Mechanism of tumor promotion and carcinogenesis. Vol. II, edited by T.J. Slaga, A. Sivak, and R.K. Boutwell, Raven Press, New York, NY (1978) pp. 491-507. 

Hecker, E., Cocarcinogens or Limited Cancer Inducing Agents. Important New Aspects of the Etiology of Human Tumors and the Molecular Mechanisms of the Origin of Cancer. Naturwissen-Schaften, 1978, 65, 640-648. 

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