Soy Protein in Preventing Recurrent Cancer in Patients Who Have Undergone Surgery for Stage II Prostate Cancer
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|ClinicalTrials.gov Identifier: NCT00765479|
Recruitment Status : Completed
First Posted : October 3, 2008
Last Update Posted : September 20, 2013
RATIONALE: Soy protein may help prevent prostate cancer recurrence in patients who have undergone surgery for prostate cancer.
PURPOSE: This randomized phase II/III trial is studying how well soy protein works and compares it to a placebo in preventing recurrent cancer in patients who have undergone surgery for stage II prostate cancer.
|Condition or disease||Intervention/treatment||Phase|
|Prostate Cancer||Dietary Supplement: soy protein isolate Other: placebo||Phase 2 Phase 3|
- Determine whether soy protein isolate reduces the PSA failure rate and time to PSA failure within 2 years following radical prostatectomy in patients who are at high risk for prostate cancer recurrence.
- Determine the effects of soy protein isolate on intermediate biomarkers of steroid hormone axis (testosterone, estradiol, and SHBG) and thyroid activity (T3 and T4).
- Determine the effects of soy protein isolate on intermediate biomarkers of apoptosis (soluble Fas and Fas-ligand), angiogenesis (VEGF and bFGF), antioxidant activity (8-isoprostanes), and IGF axis (IGF-1 and IGFBP-3).
- Compare patients who are equol producers to those who are non-producers.
OUTLINE: This is a multicenter study. Patients are stratified according to hospital/clinic site (NYU vs UIC or Jesse Brown VA Medical Center vs other sites), number of high-risk characteristics (1 vs > 1), and race (African American vs non-African American [i.e., non-Hispanic White, Hispanic, Asian, and other]). Patients are randomized to 1 of 2 treatment arms.
- Arm I: Patients receive an oral soy protein isolate beverage once daily.
- Arm II: Patients receive an oral casein placebo beverage once daily. Treatment in both arms continues for up to 2 years in the absence of disease progression or unacceptable toxicity.
Blood samples are collected periodically for biomarker laboratory studies. Samples are analyzed to measure PSA levels by Tosoh PSA assay; cholesterol levels; isoflavone and equol concentrations by HPLC and ESA; and indicators of steroid hormone axis (testosterone, estradiol, and SHBG), indicators of thyroid activity (T3 and T4), indicators of apoptosis (soluble Fas and Fas-ligand), indicators of angiogenesis (VEGF and bFGF), indicators of oxidative stress (8-isoprostanes), and indicators of IGF axis (IGF-1 and IGFBP-3) by ELISA.
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||284 participants|
|Official Title:||Randomized Placebo-Controlled Adjuvant Study of Prevention of Prostate Cancer Recurrence After Radical Prostatectomy by Soy Protein Isolate|
|Study Start Date :||December 2006|
|Actual Primary Completion Date :||September 2011|
|Actual Study Completion Date :||July 2013|
Experimental: Arm I
Patients receive an oral soy protein isolate beverage once daily.
Dietary Supplement: soy protein isolate
Placebo Comparator: Arm II
Patients receive an oral casein placebo beverage once daily.
- Two-year PSA failure rate (as surrogate for recurrence)
- Time to PSA failure
- Isoflavone uptake or compliance as measured by serum isoflavone concentration
- Serum total cholesterol levels
- Steroid hormone axis as measured by serum testosterone, estradiol, and SHBG levels
- Thyroid activity as measured by serum T3 and T4 levels
- Apoptotic activity as measured by serum soluble Fas and Fas-ligand levels
- Angiogenesis as measured by serum VEGF and bFGF levels
- Oxidative stress as measured by serum 8-isoprostane levels
- IGF axis as measured by serum IGF-1 and IGFBP-3 levels
- Equol production as measured by serum equol concentration
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): NCT00765479
|United States, Illinois|
|University of Illinois Cancer Center|
|Chicago, Illinois, United States, 60612-7243|
|Principal Investigator:||Maarten C. Bosland, DVSc, PhD||University of Illinois at Chicago|
|OverallOfficial:||Roohollah Sharifi, MD||University of Illinois at Chicago|