Journal of Carcinogenesis & Mutagenesis

Abstract

Effect of Nicotine-free Tobacco Extract on DNA Damage Responses in Cancerous and Non-cancerous Cells

Ying Yu, Pavan K Soma, Y Martin Lo, Cheng-I Wei and Wen-Hsing Cheng

The use of cigarette products tags tobacco as a crop with serious health concerns, but nutraceutical potentials of tobacco constituents other than nicotine have not been adequately explored. The objective of this study was to investigate the effect of nicotine-free tobacco extract on the activation of tumorigenesis barriers. Four lines of human cells were treated with a nicotine-free tobacco extract (0.1 and 1 mg/mL, 0-48 h). MRC-5 and CCD841 non-cancerous cells treated with the tobacco extract showed hypersensitivity, apoptosis and cell cycle arrest in S and G2/M phases, and induction of DNA damage response as evidenced by phosphorylation of ataxia telangiectasia mutated at Ser- 1981 and histone H2A.X at Ser-139. In contrast, HCT 116 cancerous cells, with or without functional DNA mismatch repair, were resistant to the tobacco extract treatment. These results suggest that tobacco components other than nicotine may have a chemoprevention potential that stifles tumorigenesis at the early stage of tumorigenesis