Gene Expression Profiling Of Buccal Epithelium Among Nonsmoking Women Exposed To Household Air Pollution From Smoky Coal

Qing LAN, National Cancer Institute, United States
ROTHMAN N. 1 , SILVERMAN D. 1 , DOWNWARD G. 3 , HU W. 1 , VERMEULEN R. 3 , WANG T. 2 , SPIRA A. 2

1 Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Bethesda, Maryland, United States
2 Division of Computational Biomedicine, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
3 Institute for Risk Assessment Sciences, Division of Environmental Epidemiology, Utrecht University, The Netherlands

Lung cancer rates in Xuanwei County are among the highest in the world for non-smoking females and have been causally associated with exposure to indoor smoky (bituminous) coal emissions. To understand the molecular effects of smoky coal exposure, we analyzed the global gene-expression profiles in buccal epithelial cells collected from healthy, non-smoking female residents of Xuanwei and Fuyuan who burn either smoky or smokeless coal. We identified a distinct gene expression signature, with enrichment of a number of pro-inflammatory genes, in the oral cells of non-smoking women exposed to smoky vs. smokeless (anthracite) coal. The gene expression signature was correlated with carcinogenic PAHs but not with non-carcinogenic PAHs and PM2.5 measured in personal air samples. In addition, there was substantial overlap between the gene expression signature found among smoky coal users and among tobacco users. Our findings provide biological insights into potential pathways associated with the elevated lung cancer risk observed in those exposed to smoky coal combustion.