EGFR and neoplasm: The expression of alpha-7 nicotinic acetylcholine receptors (nAChRs) on tumor cells promotes proliferation and migration through the phosphorylation of epidermal growth factor receptor (EGFR), protein kinase B (Akt), mammalian target of rapamycin (mTOR), and the stimulation of beta-adrenergic receptors [19,20,21].