Exercise May Reverse Obesity-Induced Immune Suppression in Lung Cancer

A study published in Annals of Surgery has shown that physical exercise can reverse the immune-suppressing effects of obesity in the lungs and tumor microenvironment, potentially enhancing the body's natural defense against non-small cell lung cancer (NSCLC). The research, led by senior investigators Sai Yendamuri, MD, MBA, FACS, and Andrew Ray, PT, PhD, of the Roswell Park Comprehensive Cancer Center, suggests that voluntary physical activity could serve as a powerful, non-invasive adjunct to standard lung cancer treatments and interception strategies.

While obesity is globally recognized as a driver of metabolic dysfunction, its specific role in paralyzing lung-localized immunity remains poorly understood. This study provides evidence of how physical activity remodels the immune landscape in both tumor-bearing and non-tumor-bearing lung tissues, presenting critical implications for oncology nursing practice.

Key Takeaways for Oncology Nurses

• The Clinical Problem: Obesity induces systemic immune dysfunction, specifically characterized by the depletion of cytotoxic T cells and the expansion of immunosuppressive regulatory T cells (Tregs) and myeloid cells in the lungs, facilitating tumor progression.
• The Physical Solution: Voluntary exercise restores local pulmonary immunity by decreasing suppressive Treg populations and preserving functional CD8+ cytotoxic T cells, directly slowing tumor growth.
• Bilateral Benefits: Exercise-induced immune restoration occurs in both tumor-bearing and non-tumor-bearing lungs, suggesting benefits for both active lung cancer therapy and cancer interception (prevention).
• Role for Nurses: Oncology nurses are uniquely positioned to integrate physical activity assessments and tailored exercise counseling into routine patient care, helping survivors overcome barriers to movement.

Study Methodology and Findings

To investigate the biological mechanisms connecting adiposity, exercise, and pulmonary immunity, the research team implemented a translational model combining mouse experiments with human clinical data.

In the preclinical arm, the researchers studied four groups of lean and obese mice implanted with Lewis lung carcinomas under either sedentary conditions or with voluntary access to an exercise wheel. Using RNA sequencing and flow cytometry, they assessed how exercise affected the tumor microenvironment and infiltrating leukocytes.

The preclinical findings were striking:

• Immune Restoration: Obese exercising mice demonstrated a less profound accumulation of immunosuppressive Tregs and suppressive myeloid cells compared to sedentary obese controls.
• CD8+ Preservation: Physically active obese mice displayed fewer CD8+ cytotoxic T-cell deficits within both the tumor and the healthy lung tissue.²
• Tumor Deceleration: Exercise led to a significant delay in overall tumor growth in obese mice, while only muted, less pronounced benefits were seen in active lean mice.
• Transcriptomic Remodeling: Active obese mice exhibited favorable transcriptomic changes in vascular and metabolic programs within the lung compartment.

To validate these findings, the researchers analyzed bronchoalveolar lavage (BAL) fluid samples from 73 patients with NSCLC. The cohort was stratified by total fat area (adiposity) and physical activity levels, with multivariable adjustments applied to control for confounding variables.

Consistently, human BAL samples from physically active patients contained significantly fewer programmed cell death protein 1-positive (PD-1+) Tregs and fewer suppressive myeloid cells that had been enhanced by adiposity. This directly mirrored the preclinical findings, confirming that regular exercise modifies the immune cells residing in human lung tissue to favor an active anti-tumor response.

Expert Perspectives on Clinical Integration

"This study demonstrates how exercise can correct immune dysfunction in the lungs to provide a stronger defense against tumors," stated Yendamuri, Chair of the Department of Thoracic Surgery at Roswell Park, in a news release.

His co-senior author, Ray, an Associate Professor of Oncology in the Department of Cancer Prevention and Control, highlighted the accessibility of the intervention: "Exercising can provide a free, non-invasive adjunct to a patient's treatment regimen that has the potential to improve outcomes."

Implications for Oncology Nursing Practice

Oncology nurses are at the forefront of managing treatment toxicities and promoting survivorship. These findings provide a strong biological rationale to advocate for physical activity, helping patients understand that exercise is not merely for cardiovascular fitness or weight loss, but serves as an immunomodulatory therapy that helps restore the body's anti-tumor response.

Furthermore, nurses should conduct routine physical activity assessments. By identifying obese or sedentary patients early, nurses can help coordinate referrals to physical therapists or supervised exercise programs. This proactive care model empowers patients, improves outcomes, and reduces the risk of cancer progression.

References

1. Obesity Weakens Anti-Tumor Immune Response in Lung Cancer – But Exercise May Restore It. Press Release. Buffalo, NY: Roswell Park Comprehensive Cancer Center; August 17, 2026.
2. Smith R, Erickson K, Washington D, et al. Exercise Modulates Adiposity-induced Immune Dysfunction in NSCLC and Non-tumor–Bearing Lungs: Implications for Lung Cancer Therapy and Interception. Ann Surg. Published online ahead of print, August 6, 2026. doi:10.1097/SLA.0000000000007151