Exercise May Help Protect Older Adults Against Cancer

Scientists have identified a biological mechanism linking aging muscle to cancer progression, revealing that aged muscle cells release fewer extracellular vesicles—tiny particles critical for cellular communication—which weakens their ability to suppress tumor growth. The study, published in Nature Communications, also found that exercise can restore this protective function, offering new insights into cancer prevention and healthy aging.

The research, led by scientists at Duke-NUS Medical School in Singapore and collaborators from Singapore General Hospital and Cardiff University, focused on sarcopenia, a condition characterized by progressive loss of skeletal muscle mass and strength. Sarcopenic muscle was found to secrete fewer extracellular vesicles, which are essential for transmitting signals between cells. These vesicles, particularly those containing the microRNA miR-7a-5p, play a key role in regulating gene expression and inhibiting tumor development.

“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, 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 tumor growth.”

The team discovered that the release of extracellular vesicles is governed by a biological pathway that declines with age but can be reactivated through physical activity. This pathway’s decline correlates with reduced levels of miR-7a-5p in aged muscle, a molecule known to restrain tumor growth. Exercise, particularly resistance and aerobic training, appears to reverse this decline, restoring the vesicles’ protective role.

“Clinically, we observe an association between advanced cancer and low muscle mass. This is a novel study which illustrates how healthy muscle can potentially inhibit tumor growth,” said Kenon Chua, a consultant in the orthopedic surgery department at Singapore General Hospital and co-author of the study.

The findings establish a direct biological link between aged muscle and cancer progression, highlighting a muscle-to-tumor communication pathway that could be targeted for therapeutic development. Researchers emphasized the importance of maintaining muscle health through exercise, especially for older adults.

“We hope that the insights from our research can help us develop new targeted therapies for our patients; as well as convince more people of the benefits of regular exercise,” Chua said.

Professor Lok Shee Mei, interim vice-dean for research at Duke-NUS Medical School, noted the broader implications of the work. “This study opens new avenues for therapeutic strategies to preserve muscle health and reduce cancer risk, while also underscoring the importance of physical activity in aging,” he said.

The study was supported by the Singapore Ministry of Education, the Diana Koh Innovative Cancer Research Award, the National Academy of Medicine, and the National Research Foundation, Singapore.

What is the role of extracellular vesicles in cancer development?
Extracellular vesicles act as messengers between cells, carrying molecules like miR-7a-5p that regulate gene expression. In aging muscle, reduced vesicle production and altered composition weaken signals that normally suppress tumor growth. This creates an environment conducive to cancer progression.

How does aging affect the composition of these vesicles?
As muscle ages, extracellular vesicles contain lower levels of miR-7a-5p, a microRNA that inhibits tumor growth. This shift in vesicle content diminishes their ability to send protective signals, potentially allowing cancer cells to proliferate.

What evidence supports the link between muscle health and cancer risk?
Clinical observations show a correlation between advanced cancer and low muscle mass. The study provides a mechanistic explanation, demonstrating that sarcopenic muscle secretes fewer protective vesicles, which may contribute to tumor development.

How does exercise counteract these effects?
Exercise reactivates a biological pathway that declines with age, restoring the release of extracellular vesicles. This process replenishes miR-7a-5p levels, enhancing the muscle’s ability to suppress tumors. The findings suggest that physical activity could be a critical intervention for older adults.

What are the next steps for this research?
The team plans to validate their findings in human samples and investigate whether extracellular vesicles, particularly those carrying miR-7a-5p, could serve as biomarkers for cancer risk associated with sarcopenia.

The study underscores the interconnectedness of musculoskeletal health and cancer biology, emphasizing the need for strategies to maintain muscle function in aging populations. As global life expectancy rises, these insights could inform public health initiatives and personalized therapies aimed at reducing cancer risk.

“Policymakers in Singapore and across the region should use this evidence to support greater investment in