Continuing to use nicotine patches or gums after cancer surgery -- to say nothing of smoking -- makes chemotherapy less effective, according to researchers at the University of South Florida.

The Associated Press reported April 2 that a study of lung-cancer patients found that nicotine appears to protect cancer cells from chemotherapy drugs like gemcitabine, cisplatin, and taxol. Srikumar Chellappan of the University of South Florida and colleagues studied the impact of nicotine on non-small cell lung cancer, the most common form of the disease.

"Our findings are in agreement with clinical studies showing that patients who continue to smoke have worse survival profiles than those who quit before treatment," the study noted. "They also raise the possibility that nicotine supplementation for smoking cessation might reduce the response to chemotheraputic agents."

The research appears in the online edition of Proceedings of the National Academy of Sciences.