Although a report is available for the role of nAChR in proliferation and differentiation of the pluripotent P19 cells derived from murine embryonal carcinoma in the literature as well [35], this is the first direct demonstration of functional expression of an nAChR subtype composed of α4β2 subunits endowed to positively regulate neuronal differentiation in cultured neural progenitor cells from fetal mouse neocortex. This evidence concerns the gene CHRNA4 and embryonal carcinoma.