Pharmaceutical compositions are provided that are useful in treating or preventing neoplastic disease, such as cancer. The compositions comprise a pharmaceutically acceptable carrier, and an effective therapeutic or prophylactic amount of a nitroxide antioxidant that alters the expression of one or more genes related to the cancer. Methods are also provided for the use of the pharmaceutical compositions in the treatment or prevention of cancer. In a preferred embodiment, the nitroxide antioxidant is Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl), and the cancer is esophageal cancer, hepatocellular carcinoma, colon cancer, prostate cancer, lung cancer, gastric carcinoma, renal cell carcinoma, bone cancer, breast cancer, cervical cancer, brain cancer, or a cancer associated with the tumor suppressor gene p53.
