According to a report issued on Sunday, nicotine can prevent chemotherapy drugs like taxol from killing lung cancer cells. The report also stated that people who do not smoke anymore, but use nicotine supplements such as patches are not getting the best out of their cancer therapy. The drugs which fight against lung cancer, gemcitabine, cisplatin and taxol, have been tested on cells taken from cancer tumors. It was discovered that the level of nicotine found in a typical smoker interfered with the chemotherapy drugs, which have the ability to kill cancer cells, even boosting the levels of two proteins which protect the harmful cells. Nicotine stopped a process called apoptosis, a kind of cell suicide. The substance is an important factor in making cigarettes addictive. Doctors accept the use of nicotine-based gum and patches to help smokers to quit because the substance is less dangerous than others contained in the cigarettes. Still, the results are not entirely clear. Some doctors warn that a walking human is very different from a dish full of cells in a laboratory. "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," researchers stated. The only clear message that the findings suggests is: "If you have cancer, stay away from nicotine - smoking or patches or gum."