This review summarises evidence relevant to the involvement of N-nitroso com/Htunds in the induction of tobacco-related cancers in man. ('ancers of the oral cavity, lung, oesophagus and pancreas will be discussed. Human exposure to nitrosamine com/>ounds in tobacco products is more intense and widespread than from any other known source. Many substances, such as N-nitroso com/founds. 4-(N-nitrosomethyIamino)-I-(3 pyrıdyl)-1-butanone and N'-nitrosonornicotine and /xilynuclear aromatic hydrocarbons available in tobacco may involve in causing cancers of the oral cavity, lung, oesophagus and pancreas in tobacco users. NNK and its metabolites have been shown to induce tumours in experimental animals. Both NNK and benzo[a/pyrene active the K-ras oncogenes with mutations in codon 12 were delected in 13 of 45 adenocarcinomas obtained from the lungs of smokers. The reduction or elimination of these substances /rom tobacco products would pnihahly lead to a decrease in the incidence of these cancers. [Journal of Turgut Özal Aiedical Center 1(4) 342-345.1994/
Key Words: Tobacco, cancer
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