The battle against cancer could be boosted after a breakthrough by scientists at Queen's University Belfast.
The university said new research could help prevent the heart damage potentially caused by chemotherapy treatments.
It is hoped the findings will help devise medicines to counteract the side-effects and reduce heart failure in cancer patients.
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.
David Grieve, jointly leading the research at Queen's School of Medicine, Dentistry and Biomedical Sciences, said: "While chemotherapy drugs are highly effective in treating a wide range of tumours, they can also cause irreversible damage to the heart.
"This means that doctors are restricted in the doses they can administer to patients. In recent years, scientists have been searching for new drugs to prevent these side-effects.
"Although we have known about the NADPH oxidase enzyme for many years, until now, we were not aware of its crucial role in causing heart damage associated with chemotherapy.
"Our research findings hold clear potential for the creation of new drugs to block the action of the enzyme, which could significantly reduce heart damage in cancer patients."
Scientists at Queen's are concentrating on further studies to define the precise role of NADPH oxidase in the development of heart failure associated with cancer therapies, which they hope may lead to the development of a drug which would have the potential to save lives.
The research by Dr Grieve and Professor Barbara McDermott was funded by the British Heart Foundation in Northern Ireland and published in leading international journal Cancer Research.