Parp-1 deficiency does not increase the frequency of tumors in the oral cavity and esophagus of ICR/129Sv mice by 4-nitroquinoline 1-oxide, a carcinogen producing bulky adducts

The impact of poly(ADP-ribose) polymerase-1 (Parp−1)-deficiency on 4-nitroquinoline 1-oxide (4NQO)-induced carcinogenesis was studied in mice with an ICR/129Sv mixed genetic background. Parp-1+/+, Parp−1+/− and Parp-1−/− animals given 4NQO for thirty-two weeks at 0.001% in their drinking water developed papillomas and squamous cell carcinomas of the tongue, palate and esophagus, but with no statistically significant variation with the Parp−1 genotype. Thus Parp-1 deficiency does not elevate susceptibility to carcinogenesis induced by a carcinogen which gives rise to bulky DNA lesions. This study also indicated that the ICR/129Sv mixed genetic background is associated with high yield induction of esophageal tumors by 4NQO.