Areca-nut toxicity in cultured human buccal epithelial cells

In cultured human buccal epithelial cells, at doses of 3-540 micrograms/ml, areca-nut extract significantly decreased viability, as determined by colony-forming efficiency, clonal growth rate, ability to take up neutral red and ability to exclude trypan blue, and also caused significant formation of DNA single-strand breaks and DNA protein cross-links. Comparisons of the areca nut-related compounds, 3-(N-nitrosomethylamino)propion-aldehyde (NMPA), 3-(N-nitrosomethylamino)propionitrile (NMPN), N-nitrosoguvacoline, N-nitrosoguvacine, arecoline, arecaidine, guvacoline and guvacine, in terms of the above endpoints, indicate that NMPA is ten times more cytopathic to buccal cells than the other agents on a molar basis. Because metabolism of NMPA can potentially yield several reactive breakdown products, including aldehydes, this study indicates that both the parent compound and its metabolites may contribute to the observed pathobiological effects. Taken together, the observed pathobiological effects of areca-nut extract and certain related compounds in cultured human buccal epithelial cells indicate that these agents may contribute to the oral carcinogenicity associated with chewing betel quid.