Breast Cancer, Obesity
Conditions
Keywords
exercise, breast cancer, prevention, obesity, estrogen metabolism, oxidative stress, IGF-1
Brief summary
RATIONALE: Exercising regularly may lower the risk of breast cancer. PURPOSE: This randomized clinical trial is studying how well exercise prevents breast cancer in healthy young women.
Detailed description
OBJECTIVES: Primary * Compare the changes in urine levels of a stable marker of oxidative stress (F\_2-isoprostanes) in healthy young women who undergo exercise training during 4 menstrual cycles vs no exercise. Secondary * Assess the changes in other metabolic factors that explain the association between physical activity and breast cancer, including: Estrogen metabolism (estrone, estradiol, estriol, 2-OHE\_1, 2-OHE\_2, 2-MeOHE\_1, 2-MeOHE\_2, 4-OHE\_1, 4-OHE\_2 \[as well as ratios of these metabolites\], insulin-like growth factor (IGF)-1 (as well as IGF-binding proteins-1, -2, and -3, insulin, glucose, body composition (including body mass index, lean mass, and body fat \[DEXA scan\]). OUTLINE: This is a randomized, controlled study. Participants are stratified according to baseline body fat percentage and age (18 to 24 years vs 25 to 30 years). Participants are randomized to 1 of 2 intervention arms. * Arm I: Participants exercise for 30 minutes 5 times a week. The intensity of exercise is increased every 4 weeks. The exercise regimen continues for up to 4 menstrual cycles. * Arm II: Participants are observed for 4 menstrual cycles. Participants in both arms undergo 24-hour collection of urine on days 7, 8, and 9 of menstrual cycles 1 and 6. F\_2-isoprostanes are measured via gas chromatography-mass spectrometry (GC/MS). Estrogens are also measured by GC/MS and include E\_1, E\_2, E\_3, 2-OHE\_1, 2-OHE\_2, 4-OHE\_1, 4-OHE\_2, 2-MeE\_1, 2-MeE\_2, 4-MeE\_1, 4-MeE\_2, and 16OHE\_1. Participants undergo blood collection, body mass measurement by dual-energy x-ray absorptiometry, and a fitness assessment twice during the 6-month study. PROJECTED ACCRUAL: A total of 400 participants will be accrued.
Interventions
BEHAVIORALexercise
5 days per week exercise for 4 months
Sponsors
National Cancer Institute (NCI)
University of Minnesota
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy women * Self-reported menstrual cycle length of 25-35 days within the past 2 months * Nonsmoker * Sedentary (exercise \< 3 times weekly within the past 6 months) * Intact ovaries and uterus * No history of gynecological problems (e.g., fibroids, endometriosis, polycystic ovary syndrome) * Female * Premenopausal * Body mass index 18.5 to 40 * Stable weight (no changes ≥ 10% within the past year)
Exclusion criteria
* No pregnancy or breast feeding within the past 6 months * No plans to become pregnant during study treatment * No cancer within the past 5 years except for nonmelanoma skin cancers * No medical condition that would prohibit participation in a vigorous program of weight-bearing aerobic exercise including, but not limited to, any of the following: * Fibromyalgia * Chronic fatigue syndrome * Metabolic disorders * Recent cardiovascular event * Orthopedic limitations * Psychiatric disorders requiring antipsychotic drugs * No uncontrolled hypertension (systolic blood pressure \[BP\] \> 160 mm Hg and/or diastolic BP \> 99 mm Hg) * No more than 7 alcoholic beverages per week * No injected hormonal contraceptive use within the past year * More than 6 months since prior use of intrauterine device * More than 3 months since prior oral or patch hormone contraceptives * No medication that would prohibit participation in a vigorous program of weight-bearing aerobic exercise
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Changes in urine levels of F2-isoprostanes | Before and after study |
Secondary
| Measure | Time frame |
|---|---|
| Changes in levels of IGF-axis proteins | Before and after study |
| Changes in insulin and glucose | Before and after study |
| Changes in estrogen metabolites | Before and after study |
| Changes in body composition | Before and after study |
Countries
United States
Outcome results
None listed