A study has found that nicotine can prevent chemotherapy drugs from killing lung cancer cells. The finding published in "Proceedings of the National Academy of Sciences" suggests that even people who quit smoking, but use nicotine patches or gum may not respond to anti-cancer drugs.
Experts say that among lung cancer patients who undergo chemotherapy, smokers tend to fair worse than non-smokers, and so do patients who quit smoking, but are using nicotine patches or gum.
While nicotine itself does not cause cancer, experts at the H. Lee Moffitt Cancer Center in Tampa, Florida, say, the addictive ingredient appears to promote tumor growth.
Researchers, led by Piyali Dasgupta, have discovered that nicotine appears to stimulate molecules that protect cancerous cells exposed to chemotherapy drugs.
"Nicotine is enabling it to survive," said Dasgupta. "If the nicotine was not there, then it would work better, a lot better. But because you are smoking and it's in your system it's kind of canceling that effect, making you less responsive to the chemotherapy."
Researchers say the study's findings may have implications for people who are trying to quit smoking after a lung cancer diagnosis.
Dasgupta says nicotine in patches and gums used by smokers to help them quit is low, but still may reduce the effectiveness of chemotherapy drugs.
"I don't have the data for that yet," admitted the researcher. "But yes. But it may be that it is low, that it does not have a significant effect. I can not give an answer to that question. But yes, it might."
There are some 400 other compounds in cigarette smoke, and Dasgupta says she and her colleagues will focus on how some of them interact with chemotherapeutic agents.
The study - entitled Nicotine Can Inhibit Lung Cancer Chemotherapy - was presented at the annual meeting of the American Association for Cancer Research, and is published in Proceedings of the National Academy of Sciences.