Randomized Controlled Trial of Aerobic Exercise on Insulin and Insulin-like Growth Factors in Breast Cancer Survivors: The Yale Exercise and Survivorship Study
Open Access
- 1 January 2009
- journal article
- research article
- Published by American Association for Cancer Research (AACR) in Cancer Epidemiology, Biomarkers & Prevention
- Vol. 18 (1), 306-313
- https://doi.org/10.1158/1055-9965.epi-08-0531
Abstract
Background: High insulin and insulin-like growth factor-I (IGF-I) levels may be associated with an increased breast cancer risk and/or death. Given the need to identify modifiable factors that decrease insulin, IGF-I, and breast cancer risk and death, we investigated the effects of a 6-month randomized controlled aerobic exercise intervention versus usual care on fasting insulin, IGF-I, and its binding protein (IGFBP-3) in postmenopausal breast cancer survivors. Methods: Seventy-five postmenopausal breast cancer survivors were identified from the Yale-New Haven Hospital Tumor Registry and randomly assigned to an exercise (n = 37) or usual care (n = 38) group. The exercise group participated in 150 minutes per week of moderate-intensity aerobic exercise. The usual care group was instructed to maintain their current physical activity level. A fasting blood sample was collected on each study participant at baseline and 6 months. Blood levels of insulin and IGF were measured with ELISA. Results: On average, exercisers increased aerobic exercise by 129 minutes per week compared with 45 minutes per week among usual care participants (P < 0.001). Women randomized to exercise experienced decreases in insulin, IGF-I, and IGFBP-3, whereas women randomized to usual care had increases in these hormones. Between-group differences in insulin, IGF-I, and IGFBP-3 were 20.7% (P = 0.089), 8.9% (P = 0.026), and 7.9% (P = 0.006), respectively. Conclusions: Moderate-intensity aerobic exercise, such as brisk walking, decreases IGF-I and IGFBP-3. The exercise-induced decreases in IGF may mediate the observed association between higher levels of physical activity and improved survival in women diagnosed with breast cancer. (Cancer Epidemiol Biomarkers Prev 2009;18(1):306–13)Keywords
This publication has 38 references indexed in Scilit:
- Exercise Improves Body Fat, Lean Mass, and Bone Mass in Breast Cancer SurvivorsObesity, 2009
- Influence of Pre- and Postdiagnosis Physical Activity on Mortality in Breast Cancer Survivors: The Health, Eating, Activity, and Lifestyle StudyJournal of Clinical Oncology, 2008
- General and Abdominal Obesity and Survival among Young Women with Breast CancerCancer Epidemiology, Biomarkers & Prevention, 2006
- Hormone Replacement Therapy and Decreased Lung Cancer SurvivalJournal of Clinical Oncology, 2006
- Relationship of Obesity and Physical Activity with C-Peptide, Leptin, and Insulin-Like Growth Factors in Breast Cancer SurvivorsCancer Epidemiology, Biomarkers & Prevention, 2005
- Physical Activity and Survival After Breast Cancer DiagnosisJAMA, 2005
- No Effect of Exercise on Insulin-Like Growth Factor 1 and Insulin-Like Growth Factor Binding Protein 3 in Postmenopausal Women: a 12-Month Randomized Clinical TrialCancer Epidemiology, Biomarkers & Prevention, 2005
- Role of the Insulin-Like Growth Factor Family in Cancer Development and ProgressionJNCI Journal of the National Cancer Institute, 2000
- Circulating concentrations of insulin-like growth factor I and risk of breast cancerThe Lancet, 1998
- Development of Questionnaire to Examine Relationship of Physical Activity and Diabetes in Pima IndiansDiabetes Care, 1990