According to a study published online August 23 in The Journal of the National Cancer Institute, nicotine promotes breast cancer. It binds to a specific receptor in the body. This promotes both nicotine addiction and breast cancer. Yuan-Soon Ho et al of the Taipei Medical University found that human breast cancer cells consistently over-expressed the alpha 9 subunit of the nAChR (nicotinic acetylcholine receptor). The expression went on becoming high with the progressive breast cancer stages.
Researchers from the institute mentioned, also found that reducing the levels of nAChR inhibited tumor growth in the experiments conducted in the laboratories and increasing its levels promoted the development of breast cancer characteristics. This was the case with treating the normal breast cells with nicotine as well. The author of the study said that the study was limited by its small sample size available. To add to it, the study was conducted only on Asian patients.
Ilona Linnoila of the Center for Cancer Research at the National Cancer Institute writes, “The study suggests not only that smoking could be casually related to breast carcinogenesis but also that nicotine could directly contribute to the molecular mechanism of carcinogenesis in addition to indirectly contributing by promoting addiction to smoking.”