Nicotinic receptor and tobacco-related cancer.

Currently, tobacco smoking causes approximately 5-6 million deaths per year including more than 35% of all cancer deaths. Nicotine, the addictive constituent of tobacco, and its derived carcinogenic nitrosamines, contribute to cancer promotion and progression through the activation of nicotinic acetylcholine receptors (nAChR). Although the role of nicotine in cancerogenesis is still discussed controversially, it has been recently shown that nicotine induces DNA damages, via induction of oxidative stress, in bronchial epithelial cells. Moreover, nicotine is able to induce muscle sarcomas in A/J mice. In this mini-review we highlight the role of nAChR and nicotine in all cancer phases (induction, promotion and progression). Relevant new findings quoted in literature and some new experiments of our laboratory were reported and discussed.