The Effect of Six Weeks of Resistance Training on Tumor Tissue VEGF and Endostatin in Mice with Breast Cancer

Tumor cells are dependent on angiogenesis to obtain oxygen and nutrients and also development of their new vascular network. VEGF as an important stimulator of angiogenesis and endostatin as an inhibitor play a fundamental role in this process. This study was designed to investigate the effect of six weeks of resistance training on tumor tissue VEGF andendostatin in mice with breast cancer. For this purpose، 20 female Balb/c mice (5-7 weeks old) became cancerous via subcutaneously transplanting of mouse adenocarcinoma tumor. After a week of rest، they were divided into resistance training and control groups and six weeks ofresistance training (three bouts per week، 50% to more than 100% of previous bout max strength) were completed. Each bout also consisted of 6-8 repetitions of climbing the ladder. Animals were killed 48 hours after the last training bout and their tumor tissue was stored. Tumor tissue endostatin proteins and VEGF were measured by western blot. Independent sample t test showed no significant difference in VEGF، endostatin and tumor volume between the two groups (P≥0. 05). As VEGF increase and endostatin decrease in skeletal muscle after exercise training likely cause angiogenesis، no changes in these two proteins in tumor tissue was probably indicative of resistance training ineffectiveness on tumor tissue angiogenesis process and growth. So this type of training can be prescribed as a safe intervention for people with breast cancer.