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Green Tea and Reduction of Breast Cancer Risk

This study has been completed.
Sponsor:
Collaborator:
National Cancer Institute (NCI)
Information provided by (Responsible Party):
University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier:
NCT00917735
First received: June 8, 2009
Last updated: January 25, 2016
Last verified: January 2016
History of Changes
  Purpose

RATIONALE: Green tea extract contains ingredients (catechins) that may lower the risk of breast cancer.

PURPOSE: This phase II trial is studying how well green tea extract works in preventing breast cancer compared to a placebo in postmenopausal women with high breast density.

The investigators have hypothesized that green tea consumption reduces breast cancer risk, and this effect is seen primarily in women who have the low-activity COMT genotype. The investigators will test this by evaluating the effects of green tea extract on breast cancer biomarkers including mammographic density, plasma insulin-like growth factor 1 (IGF-1), IGF binding protein 3 (IGFBP-3), estrone, estradiol, androstenedione, sex hormone binding globulin (SHBG), urinary estrogen metabolites and plasma F2-isoprostanes.


Condition Intervention Phase
Breast Cancer
 Drug: Green tea extract supplement
Other: Placebo
 Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Phase II, Randomized,Double-blind, Placebo-controlled, Study of the Efficacy of Green Tea Extract on Biomarkers of Breast Cancer Risk in High Risk Women With Differing Catechol-O-methyl Transferase (COMT) Genotypes

Resource links provided by NLM:

U.S. FDA Resources

Further study details as provided by University of Minnesota - Clinical and Translational Science Institute:

Primary Outcome Measures:
  • Mammographic Density [ Time Frame: Baseline and month 12 ] [ Designated as safety issue: No ]
    Percent mammographic density was measured on digital images using a computer-assisted and quantitative method.

  • Circulating Concentrations of Reproductive Hormones Including Estrone, Estradiol, Androstenedione, Testosterone, and Sex Hormone Binding Globulin (SHBG) [ Time Frame: Baseline and month 12 ] [ Designated as safety issue: No ]
    Circulating levels of reproductive hormones including estrone, estradiol, androstenedione, testosterone and SHBG were measured in fasting blood samples by liquid chromatography/tandem mass spectrometry method.

  • Circulating Concentrations of IGF Axis Proteins Including IGF-1 and IGFBP-3 [ Time Frame: Baseline and month 12 ] [ Designated as safety issue: No ]
    Circulating levels of IGF-1 and IGFBP-3 were measured in fasting blood samples by ELISA method.
Enrollment: 1075
Study Start Date: July 2009
Study Completion Date: June 2014
Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Green tea extract
Green tea extract capsules containing 80.7 % total catechins (51.7 % EGCG)
 Drug: Green tea extract supplement
Two green tea extract capsules twice daily after breakfast and dinner for one year
Other Name: Green tea extract: Corban green tea blend (GTB-3D)
Placebo Comparator: Sugar pill
Placebo capsules containing 50% maltodextrin, 49.5 % cellulose, and 0.5 % magnesium stearate
 Other: Placebo
Two placebo capsules twice daily after breakfast and dinner for one year
Other Name: Sugar Pill

Detailed Description:

OBJECTIVES:

  1. Primary:

    1.1 To determine the effects of green tea extract consumption (containing 800 mg EGCG per day) for 12 months on the following recognized biomarkers of breast cancer risk:

    1. Mammographic density
    2. Circulating concentrations of insulin-like growth factor 1 (IGF-1) and IGF binding protein 3 (IGFBP-3)
    3. Circulating concentrations of reproductive hormones (estrone, estradiol, androstenedione) and sex hormone binding globulin (SHBG)

    1.2 To determine the effects of COMT genotype on the green tea extract effects described above.

  2. Secondary:

2.1 To determine the effects of green tea extract consumption (containing 800 mg EGCG per day) for 12 months on the following hypothesized biomarkers of breast cancer risk:

  1. Urinary estrogen metabolites (estrone, estradiol, and their 2-hydroxy, 4-hydroxy, 2-methoxy, and 4-methoxy metabolites, estriol, and 16- hydroxyestrone)
  2. Circulating concentrations of F-2 isoprostanes, a recognized biomarker of systemic oxidative stress

2.2 To determine the effects of COMT genotype on the green tea extract effects described above.

2.3 To determine the effects of COMT genotype on catechin metabolism and excretion, as measured by circulating and urinary concentrations.

  Eligibility
Ages Eligible for Study:   50 Years to 70 Years   (Adult, Senior)
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Signed informed consent
  • Healthy postmenopausal women aged 50-70 years
  • "Heterogeneously dense" (51-75% glandular) or "extremely dense" (>75%glandular) breasts
  • Willing to avoid consumption of green tea for 1 year

Exclusion Criteria:

  • Positive serological markers of hepatitis B or hepatitis C infections
  • Elevated levels of liver enzymes
  • Recent (within 6 mo) or current hormone or hormone modification therapy, including systemic hormone replacement therapy, SERMS and aromatase inhibitors
  • Current smoker of cigarettes or other tobacco products
  • BMI <19 or >40 kg/m2
  • Weight change > 10 lbs during the previous year
  • History of breast cancer or proliferative breast disease
  • Regular consumption of > 7 alcoholic drinks/wk
  • Regular consumption of green tea (>1 cup/wk)
  • Recent (within 6 mo) or current use of chemopreventive agents such as tamoxifen, raloxifene or aromatase inhibitors
  • Participation in any weight loss or weight gain studies
  • Currently taking Methotrexate or Enbrel
  • History of ovarian cancer
  • Any form of cancer in the last 5 years
  • Presence of implants
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00917735

Locations
United States, Minnesota
Fairview Southdale Breast Center
Edina, Minnesota, United States, 55435
Fairview Maple Grove Breast Center
Maple Grove, Minnesota, United States, 55369
University of Minnesota Medical Center (UMMC) Breast Clinic
Minneapolis, Minnesota, United States, 55455
Park Nicollet Institute
St. Louis Park, Minnesota, United States, 55426
Food Science and Nutrition, University of Minnesota
St. Paul, Minnesota, United States, 55108
Sponsors and Collaborators
University of Minnesota - Clinical and Translational Science Institute
National Cancer Institute (NCI)
Investigators
Principal Investigator: Mindy S Kurzer, Ph.D University of Minnesota - Clinical and Translational Science Institute
  More Information

Additional Information:
The Minnesota Green Tea Trial (MGTT), a randomized controlled trial of the efficacy of green tea extract on biomarkers of breast cancer risk: study rationale, design, methods, and participant characteristics  This link exits the ClinicalTrials.gov site
The safety of green tea extract supplementation in postmenopausal women at risk for breast cancer: results of the Minnesota Green Tea Trial  This link exits the ClinicalTrials.gov site

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Responsible Party: University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier: NCT00917735     History of Changes
Other Study ID Numbers: 0806M36121  R01CA127236 
Study First Received: June 8, 2009
Results First Received: July 29, 2015
Last Updated: January 25, 2016
Health Authority: United States: Food and Drug Administration

Keywords provided by University of Minnesota - Clinical and Translational Science Institute:
Green tea
Breast cancer
Prevention
COMT genotype
EGCG (Epigallocatechin gallate)
 Mammographic density
Reproductive hormones
IGF axis proteins
Oxidative stress

Additional relevant MeSH terms:
Breast Neoplasms
Neoplasms by Site
Neoplasms
Breast Diseases
Skin Diseases

ClinicalTrials.gov processed this record on September 30, 2016