Discovery may see hike in cancer survival rates

A BREAKTHROUGH by scientists at Queen’s University Belfast could help reduce heart failure in cancer patients and ultimately increase survival rates.

Scientists at Queen’s Centre for Vision and Vascular Science have discovered the role of an enzyme which, when a patient receives chemotherapy, can cause life-threatening damage to the heart.

This has, until now, restricted the amount of chemotherapy doses a patient can receive, diluting the chemotherapy’s effectiveness in destroying cancerous tumours.

By identifying the role of the enzyme — NADPH oxidase — work can now go ahead into making chemo- therapy treatments more effective and reduce the toxic effects of cancer treatment on the heart.

Dr David Grieve, joint leader of the research at Queen’s School of Medicine, Dentistry and Biomedical Sciences, said the breakthrough held clear potential for the creation of new drugs to block the action of the enzyme and significantly reduce heart damage in cancer patients.

“Ultimately, this could allow for the safer use of higher doses of chemotherapy drugs and make the treatment more effective against tumours. Despite improved treatments, cancer is currently responsible for 25% of all mortality in the western world. By reducing the risk of heart failure associated with chemotherapy, patient survival rates could be significantly increased,” Dr Grieve said.

While scientists have long been aware of the NADPH oxidase enzyme, until now they were not aware of its crucial role in causing chemo-associated heart damage, Dr Grieve said.

Scientists at Queens are now concentrating their efforts on further studies to define the precise role of NADPH oxidase in the development of heart failure associated with cancer therapies. It is hoped that these may lead to the development of a drug which would have the potential to save lives among cancer patients.

Enzymes are proteins that catalyse (increase or decrease the rates of) chemical reactions. Around 7% of cancer patients treated with the upper limit dosage of chemotherapy agent Doxorubicin currently develop heart failure. Doxorubicin is commonly used in the treatment of a wide range of cancers.

The research by Dr David Grieve and Professor Barbara McDermott was funded by the British Heart Foundation in the North and published in leading international journal, Cancer Research.