KEY WORDS: cytochrome P450 monooxygenases, metabolism, smoking, transcription factors, xenobiotic metabolizing enzymes.
Although a number of CYP isoforms have been identified in human lung tissue, a comprehensive survey of most human pulmonary xenobiotic metabolizing enzymes in different human lung tissue compartments has not been performed.
Particular evidence stems from studies with smokers in which genetic polymorphisms of certain xenobiotic metabolizing enzymes were linked to the development of lung cancer (Bartsch et al.
Cigarette smoke may affect the capacity of lung tissue to dispose of foreign chemicals by changing expression and coded activity of xenobiotic metabolizing enzymes.
In this study we aimed to investigate the regulation of gene expression of major human pulmonary xenobiotic metabolizing enzymes as well as regulatory nuclear transcription factors in smoking and nonsmoking healthy volunteers.
To our knowledge, no study has investigated the joint contribution of DNA variants in xenobiotic metabolizing enzymes
and exposure to THMs in the pathogenesis of ALL, and only two other studies have evaluated the association between leukemia and drinking water contamination, both ecologic: one study (13) reported an inverse relationship between exposure to THMs and leukemia for adults, and the other (14) observed no relation for ALL and exposure to THMs.