According to a new study published in the American Journal of Physiology, researchers from the University of Pennsylvania in Philadelphia, Pennsylvania, mice with melanoma that exercised during chemotherapy had increased tumor shrinkage compared with mice that did not exercise during chemotherapy.
In the study, researchers sought to determine whether exercise provided cardiac protection to mice with melanoma receiving doxorubicin, a common cancer drug that causes cardiotoxicity after cumulative doses.
For the study, four groups of mice were induced with melanoma. Two groups received injections of doxorubicin, while two received placebo. Then, one group of each arm exercised during the treatment period. The exercise regimen consisted of walking on treadmills for 45 minutes daily on 5 days of the week during the 2-week treatment period. After 2 weeks, the researchers found that exercise had not reduced or increased cardiotoxicity caused by doxorubicin. All mice receiving chemotherapy showed signs of heart damage.
Surprisingly, the researchers found that the mice that exercised during chemotherapy had much smaller tumors than mice that did not exercise during treatment. The findings suggest that exercise increases the effectiveness of doxorubicin in mice with melanoma. If proven, smaller doses may be suitable in combination with exercise to reduce toxicities.
In a study of mice with melanoma, scientists from the University of Pennsylvania (Penn) in Philadelphia, found that chemotherapy shrank more tumors when combined with exercise.
Senior author Joseph Libonati, an associate professor in Penn’s School of Nursing, and colleagues were originally trying to find out if exercise could protect cancer patients against the heart damage that can result from use of the common cancer drug doxorubicin.
Although the drug is effective against a variety of cancers, one of its side effects is the potential damage it can do to heart cells. In the long term, this can cause heart failure.