Cell proliferation of rat bladder urothelium induced by nicotine is suppressed by the NADPH oxidase inhibitor, apocynin

Tobacco smoking is a major risk factor for human cancers including urinary bladder carcinoma. In previous study, nicotine enhanced rat carcinogenesis in two-stage model. Nicotine also induced cytotoxicity the urothelium short-term study. present male rats were treated with (40 ppm) drinking water co-administered NADPH oxidase inhibitor, apocynin (0, 250 or 750 mg/kg) diet 4 weeks. The treatment no clinical toxic effects. Reduction of reactive oxygen species (ROS) by was confirmed immunohistochemistry 8-OHdG urothelium. Incidences simple hyperplasia, cell proliferation and apoptosis reduced However, despite reduction (labeling index), did not affect incidence apoptosis, ROS generation kidney pelvis urothelium, addition to positivity being lower. vitro, (500 μM) generation, but cancer lines (T24 UMUC3 cells). These data suggest that oxidative stress may play role nicotine.