Oral Cell DNA Adducts in Smokers

Using high resolution mass spectrometry, quantify known DNA adducts in oral mucosa cells of 100 smokers from each ethnic group - Native Hawaiians, Whites, and Japanese Americans. DNA adducts of tobacco-specific compounds, formaldehyde, and acrolein will be quantified.

2. Analyze the urine of 100 smokers and 100 non-smokers from each of these groups for mercapturic acids of acrolein and crotonaldehyde, the F2-isoprostane 8-iso-PGF-2α, a biomarker of oxidative damage, and the prostaglandin E2 metabolite PGEM, a biomarker of inflammation, as well as total nicotine equivalents and total NNAL (smokers only). These data will provide critical information relevant to the high risk of Native Hawaiians for lung cancer, and in relationship to the DNA adduct measurements of Specific Aim 1.

3. Use newly developed high resolution mass spectrometric, high throughput DNA adductomic approach to screen for known and unknown DNA adducts to identify a comprehensive DNA modification signature derived from cigarette smoking.

Using a targeted DNA adductomic method, screen for multiple DNA modifications simultaneously. The adducts analyzed in Specific Aim 1 will be added to a list including endogenous, 1,3-butadiene-derived (in collaboration with Project 3), aldehyde-derived and nitrosamine or alkylating agent-derived DNA adducts. In parallel, apply DNA adductomic methods in an untargeted mode to investigate the presence of previously unknown DNA adducts. The unknown adducts detected by the untargeted analysis will be included in the list of targeted DNA adducts to ultimately obtain a sensitive method to assess overall DNA damage resulting from cigarette smoking.
The list of DNA adducts created in Specific Aim 3a will be applied to investigate differences in the DNA damage signature in selected samples analyzed in Specific Aim 1.