Tobacco and Public Health - TCSC Indonesia

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TOBACCO SMOKE CARCINOGENS: HUMAN UPTAKE AND DNA INTERACTIONS
Fig. 5.1 Scheme illustrating the central role of carcinogens and their DNA adducts as causes of
the multiple genetic changes observed in lung cancer after years of nicotine addiction and
cigarette smoking.
and in the ways that they process DNA adducts. These and other factors may
determine cancer susceptibility. Figure 5.1 illustrates the way in which chronic
exposure to the multiple carcinogens in cigarette smoke results in multiple genetic
changes in critical genes and to lung cancer. The same scheme can be applied to other
tobacco-related cancers, although the details may differ somewhat. This chapter will
discuss some important aspects of cancer induction as related to inhaled tobacco
carcinogens: the role of particular carcinogens as causes of tobacco-induced cancers;
quantifying carcinogen uptake in humans by measurement of urinary carcinogen
metabolites; and DNA adducts of tobacco carcinogens.
Tobacco smoke carcinogens and cancer
The potential role of tobacco smoke carcinogens in smoking-associated cancers can be
evaluated by various means, but it is important to consider levels of the compounds
in cigarette smoke and their ability to induce tumors in laboratory animals. In the
following, these factors are discussed with respect to cancers of the lung, oral cavity,
esophagus, pancreas, and bladder.