Everyone has known for decades that smoking causes cancer, but until now no one really understood how cigarette smoke causes healthy lung cells to become cancerous. Researchers from the University of California, Davis, show that hydrogen peroxide in cigarette smoke causes lung cancer. This finding may help the tobacco industry develop "safer" cigarettes by eliminating such substances in the smoke, while giving medical researchers a new avenue to developing lung cancer treatments.

Tzipora Goldkorn, senior author of the report said, "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."

In this study researchers exposed different sets of human lung cells to cigarette smoke and hydrogen peroxide and then incubated the cells for one to two days. These cells, 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.

Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal said, "Studies like this will help in the fight against tobacco related death and disease. These experiments not only pin-point new molecular targets for cancer treatment, but also identify culprits in cigarette smoke which eventually leads to cancer."

This research is published in the March 2008 print issue of The FASEB Journal.

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