Cancer patients may be able to avail a different kind of therapy soon. A drug which was identified 150 years ago may help improve radiation therapy, a new study reveals.
Scientists believe that drug called papaverine, which was used as a smooth-muscle relaxant, could make tumours more sensitive to radiation therapy.
The drug inhibits the respiration of mitochondria, the oxygen-consuming and energy-making components of cells, and sensitises model tumours to radiation, researchers at the Ohio State University in the US found.
The researchers found that the drug does not affect the radiation sensitivity of well-oxygenated normal tissues.
The study shows that modifying the papaverine molecule might improve the safety of the molecule and could represent a new class of radiosensitising drugs that have fewer side effects.
"We know that hypoxia (deficiency in the amount of oxygen reaching the tissues) limits the effectiveness of radiation therapy, and that's a serious clinical problem because more than half of all people with cancer receive radiation therapy at some point in their care," said Nicholas Denko, a professor at OSU.
The study was published in the journal Proceedings of the National Academy of Sciences.
"We found that one dose of papaverine prior to radiation therapy reduces mitochondrial respiration, alleviates hypoxia, and greatly enhances the responses of model tumours to radiation," Denko said in the study.