UK scientists have shown how an anti-rejection drug given to organ transplant recipients could increase the risk of skin cancer. Azathioprine, is already known to be a toxic drug, and to up skin cancer risk. A Cancer Research UK team found the drug alters DNA, which can trigger cancer when a user is also exposed to ultraviolet light. Patients on this drug should take extra care when in the sun, they told Science magazine. Azathioprine is also used to treat conditions where the immune system needs controlling, such as arthritis and inflammatory bowel disease. Dr Peter O’Donovan, from Cancer Research UK’s London Research Institute in Hertfordshire, along with colleagues from Barts and The London Queen Mary’s School of Medicine and Dentistry, King’s College London and the Open University of Milton Keynes, looked at how the drug acted on cells in the lab. They found that the active form of the drug accumulates in the DNA - the genetic material - of cells. And when these cells are exposed to low doses of ultraviolet A light - one of the sun’s harmful rays - it triggers DNA mutations.
