Aging Muscle and Cancer Growth: The Role of Extracellular Vesicles

Aging muscles release fewer extracellular vesicles—tiny communication particles between cells—which may contribute to increased cancer growth, according to research published in Nature Communications by scientists at Duke-NUS Medical School. The study demonstrates that as muscle tissue ages, particularly in cases of sarcopenia, the composition of these vesicles changes, losing protective microRNA molecules that normally suppress tumor development. Researchers found that exercise can reactivate the biological pathways required to restore these protective signals, suggesting a direct link between physical activity and cancer prevention.

How Muscle Cells Communicate With Tumors

Muscle cells function as more than just physical support for the body; they act as an active endocrine organ. According to the Duke-NUS research team, these cells release extracellular vesicles (EVs) to influence the behavior of neighboring cells. In healthy, younger muscle, these vesicles carry molecular “instructions” that help maintain cellular balance and restrain tumor growth. As individuals age, the production of these vesicles declines. Furthermore, the remaining vesicles often lack adequate levels of miR-7a-5p, a microRNA molecule responsible for gene expression regulation. Without this specific molecular cargo, the muscle’s ability to signal against tumor progression is significantly weakened.

The Link Between Sarcopenia and Cancer

Sarcopenia, the age-related loss of skeletal muscle mass and strength, is clinically associated with a higher risk of advanced cancer. Assistant Professor Tang Hong-Wen and his colleagues identified that the biological pathway controlling the release of these tumor-suppressing vesicles becomes dormant with age. Kenon Chua, a consultant in the orthopedic surgery department at Singapore General Hospital, notes that this research provides a mechanistic explanation for why patients with lower muscle mass may face more aggressive cancer outcomes. By establishing this muscle-to-tumor communication pathway, the study confirms that muscle health is a critical component of the body’s natural defense against malignancy.

Can Exercise Restore Protective Signaling?

Physical activity serves as a primary intervention for maintaining the secretory function of muscle tissue. The study findings indicate that resistance and aerobic exercises can reactivate the pathways responsible for the production of healthy extracellular vesicles. By engaging in regular physical activity, older adults may effectively “reboot” the communication signals that inhibit tumor development. Professor Lok Shee Mei, interim vice-dean for research at Duke-NUS, emphasizes that these findings underscore the necessity of integrating exercise-based interventions into public health programs aimed at healthy aging.

Future Directions in Cancer Therapy

The research team is currently working to validate these findings in human clinical samples. The goal is to determine whether extracellular vesicles and their cargo, specifically miR-7a-5p, can serve as reliable biomarkers to assess cancer risk in individuals with sarcopenia. If successful, these findings could lead to the development of new, targeted therapies that mimic the protective effects of healthy muscle, offering a novel approach to cancer prevention for aging populations.

Quick Facts: Muscle Health and Cancer Risk

• Primary Mechanism: Aging muscle releases fewer extracellular vesicles, which are essential for cell-to-cell communication.
• Molecular Change: Aged muscle vesicles show reduced levels of miR-7a-5p, a molecule that helps suppress tumor growth.
• Intervention: Resistance and aerobic exercise have been shown to reactivate the biological pathways that restore these protective signals.
• Clinical Association: There is a documented correlation between low muscle mass (sarcopenia) and advanced cancer progression.