Abstract 4502: Molecular Impact of in Vitro Exposure to Electronic Cigarette Vapor in Human Bronchial Epithelium

Electronic cigarettes (ECIGs) are an emerging alternative tobacco product thought by some to potentially be safer than traditional tobacco cigarettes (TCIGs). Despite the increasing prevalence of ECIG use, few studies have evaluated the potential physiological effects of ECIG exposure. In this study we aimed to determine the global gene expression effects of ECIG exposure on bronchial epithelium in vitro. Human bronchial epithelial cells (HBECs) grown at Air Liquid Interface (ALI) were exposed to TCIG smoke and ECIG vapor derived from tobacco or menthol flavored products with and without nicotine. We identified a number of gene expression alterations that were induced by both ECIG and TCIG exposure as well as a novel set of changes uniquely induced by ECIG exposure. ECIG exposure induced the expression of genes involved in oxidative and xenobiotic stress pathways and increased the production of reactive oxygen species, similar to, but generally lower in magnitude than, the effects of TCIGs. Furthermore, TCIG and ECIG exposure both decreased the expression of genes involved in cilia assembly and movement, suggesting that the integrity of the bronchial epithelium is concordantly impaired by both exposures. We additionally identified a number of ECIG-specific cell cycle and cell division pathway changes. Finally, we observed that ECIG-induced changes were dependent on both flavor and nicotine content. Together, these results indicate that ECIG vapor can induce cellular stress and molecular alterations within airway epithelium that share similarities with the effects of TCIG smoke. Based on these findings, further studies are warranted to determine whether ECIG use will lead to similar deleterious health outcomes as those caused by TCIGs. Citation Format: Elizabeth Moses, Teresa Wang, George R. Jackson, Sean Corbett, Eduard Drizik, Daniel Brooks, George O’Connor, Catalina Perdomo, Steven Dubinett, Patrick Hayden, Marc E. Lenburg, Avrum Spira. Molecular impact of in vitro exposure to electronic cigarette vapor in human bronchial epithelium. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4502.