Abstract 3239: Molecular biomarkers and indoor household air pollution in a rural area of China

Abstract

Abstract To explore the influence of fuel source used for home heating and cooking on biomarkers of potential genomic instability, we analyzed biological samples obtained from a cross-sectional study of 104 female never-smokers enrolled from 30 villages in Xuanwei and Fuyuan in Yunnan Province, a rural region with a high incidence of lung cancer in China. Study subjects who used primarily smoky (i.e., bituminous) coal (n=80), smokeless coal (i.e., anthracite) (n=14) and wood (n=10) were analyzed. Personal 24-h air PM2.5 and polycyclic aromatic hydrocarbon concentrations were measured over two consecutive days in each household. DNA was extracted from peripheral white blood cells. We assayed molecular biomarkers of potential genomic instability including the Alu copy number to albumin gene (ALB) ratio (Alu/ALB), 5.8S ribosomal DNA to ALB ratio (5.8S rDNA/ALB) and 18S ribosomal DNA to ALB ratio (18S rDNA/ALB), which were weakly to highly correlated with each other. Multiple linear regression was performed to analyze the association between fuel type and these biomarkers, adjusted for age, as well as the influence of benzo[a]pyrene (BaP) and PM2.5 concentration. There was a significant difference (p = 0.041) in levels of 18S rDNA/ALB among the three exposure groups [mean (standard deviation [sd]) = 1.30 (0.42), 1.58 (0.72), and 1.65 (0.62) among smoky, smokeless coal and wood users, respectively]. There were substantial differences in personal PM2.5 exposure among smoky coal, smokeless coal, and wood users [mean (sd) =184 (127), 227 (318), and 433 (284) µg/m3, respectively, p = 0.0004]. PM2.5 exposure was significantly and positively associated with 18S rDNA/ALB (p = 0.001). Further, after adjustment for PM2.5, the association between fuel type and 18S rDNA/ALB became non-significant (p = 0.24). Similar positive associations were observed between PM2.5 and 5.8S rDNA/ALB (p=0.009) and Alu/ALB (p=0.0003). There were no associations identified between BaP and these biomarkers after adjustment for PM2.5. Our findings suggest that exposure to PM2.5, which has been associated with increased risks of lung cancer and cardiovascular disease, may alter potential molecular markers of genomic instability. Additional studies are needed to confirm these findings and further understand the role of these biomarkers in predicting human health effects. Citation Format: Wei Hu, Richard M. Cawthon, George Downward, Boris Reiss, Jihua Li, Jun He, Jun Xu, Wei Jie Seow, Bryan A. Bassig, Jason Y. Wong, Dean Hosgood, Lützen Portengen, Nathaniel Rothman, Roel Vermeulen, Qing Lan. Molecular biomarkers and indoor household air pollution in a rural area of China [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3239.