A 150-year-old drug might improve radiation therapy for cancer

A drug first identified 150 years ago and used as a smooth-muscle relaxant might make tumors more sensitive to radiation therapy. Researchers found that the drug papaverine inhibits the respiration of mitochondria, the oxygen-consuming and energy-making components of cells, and sensitizes model tumors to radiation. They found that the drug does not affect the radiation sensitivity of well-oxygenated normal tissues.