A new treatment developed by scientists at the University of Manchester could seriously improve the survival rates for patients undergoing radiotherapy treatment for cancer.
By treating patients with both radiotherapy and immunotherapy, the risk of cancerous cells becoming resistant to treatment could be eliminated.
The researchers found that combining the two treatments helped the immune system to track down and kill cancerous cells that survived the first bout of radiotherapy. The test subjects were mice suffering from cancer of the breast, skin and bowel.
Radiotherapy is a well-known method of killing or controlling malignant cells. More than half of all cancer patients undergo the treatment. For many types of cancer it is very successful, but any cancer cells that it fails to kill can become resistant to it. The treatment can switch on a ‘flag’ on the surface of an unaffected cell, called PD-L1. This tricks the body into thinking that the cancerous cells are harmless.
Immunotherapy works by injecting an antibody into the blood stream, which blocks the ‘flags’ and alerts the body to the danger posed by the cells. The immune system then kicks into play and destroys them. In this series of experiments, it was found that the combination of the treatments protected the mice from the possibility of the disease returning.
The lead researcher, Dr Simon Dovedi, who is also a member of the Manchester Cancer Research Centre, said: “Using the body’s own defences to treat cancers has huge potential with early phase clinical trials demonstrating exciting patient benefit but we are still at the early stages of understanding how best to use these types of treatments.
“Combining certain immunotherapies with radiotherapy could make them even more effective and we’re now looking to test this in clinical trial to see just how much of a difference it could make.”
The chief clinician of Cancer Research UK, Professor Nic Jones, said: “Around half of all cancer patients are given radiotherapy and it has been at the heart of helping improve survival rates so that today one in two cancer patients will survive for at least ten years.
“Doctors and researchers are constantly looking for ways to improve treatments and this approach could open the door to a whole new way of giving radiotherapy.”
The work undertaken by the researchers was funded by MedImmune, a subsidiary of AstraZeneca specialising in biotechnology. The Director of Oncology Research at the company, Dr Robert Wilkinson, said: “MedImmune is committed to developing strong science led collaborations, and supporting research that helps further advance our scientific understanding in the important area of immunotherapy. The findings described in the recent study with Cancer Research UK are extremely encouraging.”