Thank you for visiting our poster presenting the associations between urinary biomarkers of tobacco toxicants and lung cancer incidents in smokers using data from the multi-ethnic cohort study. Natural relationships to disclose. Locally, lung cancer is the second most common cancer in men and women. Smoking is the primary risk factor. However, only 11 to 14% of smokers will develop lung cancer in their lifetime. Also, risk of smoking-related lung cancer has been found to differ across sex and race ethnicity. We hypothesize that the inter-individual differences in risk among smokers may in part be due to the variations in exposure to specific tobacco smoking-related toxicants. This study was conducted using the multi-ethnic cohort study. Funded by the NCI in 1993, participants were recruited from the state of Hawaii and Los Angeles County in the state of California. The cohort comprises of over 200,000 men and women who are 45 to 75 years of age at time of enrollment. From primarily five racial ethnic groups, African American, Japanese American, Latino, Native Hawaiian, and Whites, we had collected epidemiologic data using questionnaire as well as biospecimens approximately 10 years after cohort entry. Participants were followed prospectively with cancer incidents that was identified through record linkage to the California and Hawaii Cancer Registries. This study utilizes data from a program project grant led by Dr. Stephen Hecht at the University of Minnesota. In a sub-cohort of 2,309 multi-ethnic cohort participants who are current smokers at the time of biospecimen collection, smoking-related biomarkers were measured from first morning urine or overnight urine. There are approximately 400 to 600 participants in each racial ethnic group and below in the black font is a list of all the measured urinary biomarkers. The study began at age of urine collection and ended at one of the following time points, diagnosis of lung cancer, death, or end of follow-up December 31, 2017. 140 incident lung cancer cases occurred during follow-up. Toxoproportional hazard models were used to assess risk of lung cancer. All models were adjusted for decade of birth, sex, race, ethnicity, BMI, pack years, and creatinine. Additional adjustments for T and E were conducted to assess if associations for these biomarkers were independent of smoking dose as well as mutual adjustments for any other identified statistically significant biomarkers. This table presents our statistically significant findings. When testing 13 urinary biomarkers of smoking, we found that three biomarkers were significantly associated with lung cancer risk even after accounting for self-reported smoking history and for the smoking dose measured by total nicotine equivalent and when adjusting for the biomarkers listed on this table. We found that a twofold increase in 2A6 enzymatic activity ratio, which was also found to have influenced smoking dose, was associated with a 21% increase in lung cancer risk. A twofold increase in acrolein was associated with a 30% increase in risk and a twofold increase in cadmium was associated with 38% increase in lung cancer risk. For urinary cadmium, this association was stronger for adenocarcinoma. In conclusion, urinary biomarkers of smoking-related toxicants were found associated with lung cancer risk independent of self-reported smoking history and each other. These biomarkers may be informative of lung cancer risk beyond self-reported data and replication of study findings in other cohorts are in progress. To thank all the co-authors of this project, as well as the multi-ethnic cohort study participants for their effort and time in answering questionnaire and providing biospecimen samples.

urinary biomarkers

lung cancer incidents

multi-ethnic cohort study

2A6 enzymatic activity ratio

cadmium