Nguyen et al. (2019) used RT-PCR and Western blotting to analyze the expression of nAChRs and found that the expression of α9 nAChR mRNA was higher that of the other nAChR subunits in three melanoma cell lines (A375, A2058, and MDA-MB-435) and a primary melanocyte cell line (HEMn-LP), and that it was higher in melanoma cells than in melanocytes. The gene discussed is CHRNA4; the disease is melanoma.