Published in Nature Communications, the study found that ageing muscles release fewer extracellular vesicles—tiny particles that enable cells to communicate with one another. These vesicles also undergo age-related changes that weaken protective signals capable of suppressing tumour growth.

The researchers found that exercise can help restore the production and function of these vesicles, offering new insights into healthy ageing, cancer prevention and the development of targeted therapies for older adults.

The effects of ageing muscles are particularly evident in sarcopenia, an age-related condition characterised by the loss of skeletal muscle mass and strength. In Singapore, nearly one in three adults aged 60 and above is affected by the condition, which reduces mobility, independence and overall quality of life.

Working with collaborators from Singapore General Hospital and Cardiff University, the Duke-NUS team discovered that sarcopenic muscle secretes significantly fewer extracellular vesicles. The vesicles also contain lower levels of miR-7a-5p, a microRNA that regulates gene expression and plays an important role in suppressing tumour growth.

The scientists further identified that the release of these extracellular vesicles is controlled by a biological pathway that declines with age but can be reactivated through regular exercise.

"Muscle cells use extracellular vesicles to send messages and influence how other cells behave, but exactly how these messages are delivered and received is not fully understood," said Assistant Professor Tang Hong-Wen from the Cancer & Stem Cell Biology Signature Research Programme at Duke-NUS Medical School and senior author of the study.

"Our research uncovers this hidden process, showing that as muscles weaken with age, these signals can change in ways that can promote tumour growth," Tang said.

Dr Kenon Chua, Consultant in the Department of Orthopaedic Surgery at Singapore General Hospital and a co-author of the study, said the findings reinforce the importance of maintaining muscle health through regular physical activity.

"Healthy muscles secrete many physiologically important molecules. With advanced age, it becomes even more important to engage in regular resistance and aerobic exercise to maintain healthy muscle mass. This is important not only for function and mobility but also for overall health," Chua said.

The researchers said their findings establish a direct biological link between ageing muscle and tumour growth, revealing a previously unknown muscle-to-tumour communication pathway that could be targeted to slow cancer progression.

Professor Lok Shee Mei, Interim Vice-Dean for Research at Duke-NUS Medical School, said the findings highlight the value of exercise in healthy ageing while opening new possibilities for therapies aimed at preserving muscle health and reducing cancer risk.

The research team now plans to validate the findings in human samples and investigate whether extracellular vesicles, particularly those carrying miR-7a-5p, could serve as biomarkers for assessing cancer risk in people with sarcopenia.

The study was supported by Singapore's Ministry of Education and the Diana Koh Innovative Cancer Research Award.