Meng-Shu Tsai1, Min-Liang Kuo2, Cheng-Chi Chang3, Ying-Tai Wu4. 1. School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan Department of Rehabilitation, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan. 2. Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan. 3. Graduate Institute of Oral Biology, School of Dentistry, National Taiwan University, Taipei, Taiwan. 4. School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.
Abstract
BACKGROUND: Vascular endothelial growth factor (VEGF) affects tumor growth and metastasis by mediating angiogenesis. Vascular endothelial growth factor overexpression is considered a predictor of poor prognosis in cancer patients. Exercise may increase the circulating levels of VEGF, which is important to angiogenesis. We examined the effects of exercise training on VEGF levels and tumor growth in male C57BL/6 mice inoculated with Lewis lung cancer cells. METHODS: Thirty-two mice were randomly assigned to either the tumor control (TC, n=16) group or the tumor exercise (TE, n=16) group. Half of the mice in TE group received aerobic interval exercise training, and the other half received aerobic continuous exercise training for 4 weeks. The animal weights and tumor volumes were assessed three times per week. Serum VEGF levels were determined at baseline, 2 and 4 weeks. The solid tumor, lung and liver were excised and evaluated at study completion. RESULTS: There was a significant increase in VEGF levels after the 4-week exercise training program in TE group, but no significant changes were observed in TC group. CONCLUSIONS: Although exercise training increased serum VEGF levels, group differences were not evident in our study. Exercise training did not alter the survival rate or tumor growth in tumor-bearing mice.
BACKGROUND:Vascular endothelial growth factor (VEGF) affects tumor growth and metastasis by mediating angiogenesis. Vascular endothelial growth factor overexpression is considered a predictor of poor prognosis in cancerpatients. Exercise may increase the circulating levels of VEGF, which is important to angiogenesis. We examined the effects of exercise training on VEGF levels and tumor growth in male C57BL/6 mice inoculated with Lewis lung cancer cells. METHODS: Thirty-two mice were randomly assigned to either the tumor control (TC, n=16) group or the tumor exercise (TE, n=16) group. Half of the mice in TE group received aerobic interval exercise training, and the other half received aerobic continuous exercise training for 4 weeks. The animal weights and tumor volumes were assessed three times per week. Serum VEGF levels were determined at baseline, 2 and 4 weeks. The solid tumor, lung and liver were excised and evaluated at study completion. RESULTS: There was a significant increase in VEGF levels after the 4-week exercise training program in TE group, but no significant changes were observed in TC group. CONCLUSIONS: Although exercise training increased serum VEGF levels, group differences were not evident in our study. Exercise training did not alter the survival rate or tumor growth in tumor-bearing mice.