Green Tea and Reduction of Breast Cancer Risk
Palabras clave
Abstracto
Descripción
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.
fechas
Verificado por última vez: | 12/31/2015 |
Primero enviado: | 06/07/2009 |
Inscripción estimada enviada: | 06/08/2009 |
Publicado por primera vez: | 06/09/2009 |
Última actualización enviada: | 01/24/2016 |
Última actualización publicada: | 02/21/2016 |
Fecha de los primeros resultados enviados: | 07/28/2015 |
Fecha de los primeros resultados de CC enviados: | 01/24/2016 |
Fecha de los primeros resultados publicados: | 02/21/2016 |
Fecha de inicio real del estudio: | 06/30/2009 |
Fecha estimada de finalización primaria: | 05/31/2014 |
Fecha estimada de finalización del estudio: | 05/31/2014 |
Condición o enfermedad
Intervención / tratamiento
Drug: Green tea extract
Other: Sugar pill
Fase
Grupos de brazos
Brazo | Intervención / tratamiento |
---|---|
Experimental: Green tea extract Green tea extract capsules containing 80.7 % total catechins (51.7 % EGCG) | Drug: Green tea extract Two green tea extract capsules twice daily after breakfast and dinner for one year |
Placebo Comparator: Sugar pill Placebo capsules containing 50% maltodextrin, 49.5 % cellulose, and 0.5 % magnesium stearate | Other: Sugar pill Two placebo capsules twice daily after breakfast and dinner for one year |
Criterio de elegibilidad
Edades elegibles para estudiar | 50 Years A 50 Years |
Sexos elegibles para estudiar | Female |
Acepta voluntarios saludables | si |
Criterios | 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 |
Salir
Medidas de resultado primarias
1. Mammographic Density [Baseline and month 12]
2. Circulating Concentrations of Reproductive Hormones Including Estrone, Estradiol, Androstenedione, Testosterone, and Sex Hormone Binding Globulin (SHBG) [Baseline and month 12]
3. Circulating Concentrations of IGF Axis Proteins Including IGF-1 and IGFBP-3 [Baseline and month 12]