Researchers Study Possible Link Between E-Cigarette Smoke and Lung Cancer
Posted: Wednesday, October 30, 2019
Mice exposed to electronic-cigarette (e-cigarette) smoke developed lung adenocarcinoma and bladder hyperplasia, according to a preclinical research study published in the journal Proceedings of the National Academy of Sciences of the United States of America. Moon-shong Tang, PhD, of the New York University (NYU) School of Medicine, New York, and colleagues, suggest that their experimental data in model systems warrants more in-depth study in the future.
“Tobacco smoke is among the most dangerous environmental agents to which humans are routinely exposed, but the potential of e-cigarette smoke as a threat to human health is not yet fully understood,” said Dr. Tang in an NYU press release. “Our study results in mice were not meant to be compared to human disease, but instead argue that e-cigarette smoke must be more thoroughly studied before it is deemed safe or marketed that way.”
For 54 weeks, 40 apparently healthy mice were exposed to e-cigarette smoke. At the end of the 54 weeks, the mice were killed, and their organs were examined for tumor formation. The slides of lung and bladder samples were analyzed by three pathologists. Of the total, 9 developed lung adenocarcinomas and 23 developed bladder urothelial hyperplasia. Although mice with lung tumors had a slightly higher rate of urothelial hyperplasia, the authors said the difference was not significant enough to establish a causal link.
“Our results support the argument that the nicotine-derived DNA adducts are likely the main causes for carcinogenesis in mice exposed to e-cigarette smoke,” stated study coauthor Herbert Lepor, MD, also of NYU Langone. “Our next step in this line of work will be to expand the number of mice studied, to shorten and prolong e-cigarette exposure time, and to further investigate the genetic changes caused by e-cigarette smoke.”
Disclosure: The study authors reported no conflicts of interest.