Recent research has provided new insights into how exercise may reduce tumor growth, particularly in mice, and possibly in humans as well. A study led by Rachel Perry at Yale School of Medicine examined the metabolic effects of exercise on cancer cells by injecting breast cancer cells into 18 mice, some of which were on a diet that induced obesity. The study allowed half of the mice to exercise voluntarily on a wheel.
Results showed that after four weeks, tumors in the obese mice that exercised were 60% smaller than those in their sedentary counterparts. The exercise was correlated with increased oxygen and glucose uptake in muscle tissue, alongside reduced glucose uptake in tumors. The researchers identified 417 genes involved in metabolic pathways that were altered due to exercise, highlighting a shift in glucose metabolism favoring muscle cells over cancer cells.
The findings suggest that exercise creates a more favorable metabolic environment for muscle cells, which may inhibit tumor growth. One significant observation was the down-regulation of mTOR, a protein related to cell growth, in cancer cells during exercise.
While these findings stem from animal studies, the researchers believe that similar mechanisms may apply to humans, even those without obesity. Previous studies have indicated similar metabolic changes in cancer patients who engage in physical activity. Experts suggest that exercise could be viewed as a critical component of cancer treatment, potentially functioning alongside traditional therapies.
Overall, this research underscores the complex interplay between exercise, metabolism, and cancer, indicating that maintaining muscle mass and engaging in regular physical activity may be vital for cancer prevention and management. Further clinical trials are necessary to confirm these effects in human subjects.