Chemoprophylaxis by Interferons or Inducers against Chemical Carcinogenesis

Human malignancies arise commonly after exposure to environmental carcinogens. Bladder cancer is a well-studied and excellent preclinical model for this process. Transitional cell carcinoma (TCC) of the lower urinary tract accounts for approximately 4% of human cancers. Most of the TCC arise in the urinary bladder, with a male:female ratio in the U.S. of about 3:1. Chemical carcinogen-induced mouse and rat tumors in situ and transplantable bladder cancer models, which mimic the pathogenesis of the human disease, have been developed (1–4). Neoplasms can be histologically graded and staged in a manner similar to that for human bladder carcinoma.