Effects of Soy Compounds on Breast Cancer, Prostate Cancer, and Bone Health
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|ClinicalTrials.gov Identifier: NCT00200824|
Recruitment Status : Completed
First Posted : September 20, 2005
Last Update Posted : March 12, 2009
|Condition or disease||Intervention/treatment||Phase|
|Breast Cancer Prostate Cancer||Drug: Soy Isoflavone Nutritional Supplements||Phase 2|
In the United States, consumption of soy products has dramatically increased in the past several years. Foods made from soy are high in isoflavones and evidence suggests that these isoflavones, genistein in particular, have many beneficial properties such as alleviating menopausal side effects and reducing the risk of osteoporosis, breast cancer, and prostate cancer. However, this data has been derived largely from studies with animal or cell models; human trials are limited. This study will determine the effects of soy isoflavones on quality of life and cancer and bone density markers.
While isoflavones have been purported to inhibit the proliferation of cancer cells, the concentrations required for this anti-cancer effect were determined to be much higher than the concentrations that can be achieved in plasma after intake of isoflavones. Recent animal studies have suggested that isoflavones may be concentrated 10-fold in tissue compared to blood concentrations. If this is true, then the higher concentration would be in the range found in the cancer cell line research to be protective of cancer. This study will determine whether tissue concentrations are similar to, higher than, or different than blood concentrations.
This study will last 5 years and will comprise three populations: men with prostate cancer on androgen ablation therapy, postmenopausal women on hormone replacement therapy (HRT), and postmenopausal women not on HRT. Participants will be randomly assigned to receive either isoflavone or placebo for two to four weeks. Participants' serum and serum extracts will be incubated with cultured human cell lines (prostate cancer, breast cancer and osteoblasts) and estrogenic and non-estrogenic mechanisms of action investigated. The human sera data will be complemented by parallel studies of direct addition of crystalline isoflavones (genistein, daidzein and equol) to the same cultured human cell lines. Participant's serum and urine also will be tested for markers of bone resorption and formation. Quality of life issues will be assessed with questionnaires.
|Study Type :||Interventional (Clinical Trial)|
|Intervention Model:||Crossover Assignment|
|Official Title:||Effects of Soy Isoflavones on the Prostate, Breast and Bone|
|Study Start Date :||May 2000|
|Study Completion Date :||January 2005|
- Markers of Bone Density
- Basic Science (e.g., proliferation of cancer cells in vitro)
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00200824
|United States, California|
|Stanford, California, United States, 94305-5705|
|Principal Investigator:||Christopher Gardner||Stanford University|