29 February 2008
"Safer" Cigarettes Back On The Agenda
by Kate Melville
Everyone knows that smoking can kill, but until now no one really understood how cigarette smoke causes healthy lung cells to become cancerous. Smoking accounts for the vast majority of lung cancer deaths, causing 90 percent of all lung cancer deaths in men and about 80 percent in women.
Now, after a series of experiments using human tissue, researchers from the University of California, Davis, believe that the cancer causing chemical is hydrogen peroxide. The researchers hope that the finding will help the tobacco industry develop "safer" cigarettes by eliminating such substances in the smoke.
"With the five-year survival rate for people with lung cancer at a dismally low 15.5 percent, we hope this study will provide better insight into the identification of new therapeutic targets," said Tzipora Goldkorn, lead author of the report.
Writing in The FASEB Journal, Goldkorn describes how his team exposed different sets of human lung airway cells (in the laboratory) to cigarette smoke and hydrogen peroxide. After exposure, these cells were then incubated for one to two days. Then they, along with unexposed airway cells, were assessed for signs of cancer development. The cells exposed to cigarettes smoke and the cells exposed to hydrogen peroxide showed the same molecular signatures of cancer development, while the unexposed cells did not.
"These experiments not only pin-point new molecular targets for cancer treatment, but also identify culprits in cigarette smoke that eventually will do the smoker in," noted Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal.
Source: Federation of American Societies for Experimental Biology