The strategic use of genetic polymorphisms in carcinogen metabolizing enzyme for prevention of cancer

Prevention is an important and effective measure for reducing death caused by cancer. Thus information on individual susceptibility to cancer is valuable in suggesting high-risk individuals to avoid intake of carcinogenic substances and undergo frequent physical examinations. To this end, polymorphisms found within cytochrome P450 genes implicated in metabolism of procarcinogens are expected to be good genetic targets in assessing human cancer susceptibility. The present auther has shown the polymorphisms within arylhydrocarbon receptor (AHR) gene, which is responsible for inducing CYP1A1, an enzyme activating carcinogens in cigarette smoke, does not significantly associate with lung cancer susceptibility in the Japanese population, in contrast to mouse animal model, whose susceptibility is known to be governed by AhR polymorphisms. A newly identified polymorphism in CYP1A1 itself, however, may determine lung cancer susceptibility.