PITTSBURGH, Dec. 29 -- A gene for a protein that fuels lung cancer growth is more active in women than in men, according to a report by a University of Pittsburgh-led research team, which also discovered that nicotine found in cigarettes induces gene activity. Their report, published in the Jan. 5 issue of the Journal of the National Cancer Institute, offers the first biological explanation for the greatly increased risk women face versus men in developing lung cancer. If substantiated in future studies, this research could provide a valuable marker for predicting which women are most likely to develop the disease or dangerous pre-cancerous changes.
The research team found in women an increase in the expression of the gene for gastrin-releasing peptide receptor (GRPR), which is found on the surface of cells lining the lung. When stimulated by its hormone, gastrin-releasing peptide, GRPR triggers cell proliferation typically seen in lung cancer. The Pittsburgh-based research team also discovered that nicotine found in cigarettes stimulates expression of the GRPR gene in lung cells.
"Our research strongly suggests that women are likely to develop lung cancer after much less smoking exposure than men and much earlier in life, regardless of their smoking history, said Sharon Shriver, Ph.D., principal investigator on the study who is now an instructor of biology at the University Park campus of Pennsylvania State University. "The take-home message, especially for teenage girls, is that they should stop smoking or, better yet, never start."
"Prior reports have suggested various molecular markers associated with an increased risk in women smokers; however, ours is the first study to provide a mechanism for cancer promotion in this population," said Jill Siegfried, Ph.D., senior author on the paper, professor of pharmacology at the University of Pittsburgh and co-director of the University of Pittsburg
Contact: Lauren Ward
University of Pittsburgh Medical Center