CHRNA7 and non-small cell lung carcinoma: In the current study, three human NSCLC cell lines (NCI-H322, NCI-H441, NCI-H1299) were used to test the hypothesis that acute or chronic nicotine-induced modulation of α7nAChR and α4β2nAChR may contribute to the development and progression of AC in smokers in a manner similar to changes in these receptors in the nicotine-addicted brain, and that these effects can be neutralized by γ-amino butyric acid or a general beta-blocker such as propranolol.