Role of Soy Supplementation in Prostate Cancer Development

Role of Soy Isoflavones in Prostate Cancer Prevention

This is a randomized study evaluating the effectiveness and direct effect a commercial soy supplement has on prostate cancer and normal prostate tissue. Patient will be randomized it either receive placebo or a commercial soy supplement for 2-4 weeks prior to the planned surgery for treatment of their prostate cancer. Patient's blood and prostate tissue will be evaluated to determine the effects of the soy supplement on the prostate tissue.

Study Overview

• Status: Completed
• Conditions: Prostate Neoplasm
• Intervention / Treatment: Drug: Placebo; Drug: Soy Supplement

Detailed Description

This is a randomized study evaluating the effectiveness and direct effect a commercial soy supplement has on prostate cancer and normal prostate tissue. Patients will be randomized to either receive placebo or a commercial soy supplement for 2-4 weeks prior to the planned surgery for treatment of their prostate cancer. The specific objectives are:

1. To assess the effect of soy supplementation on endogenous hormone production levels and serum prostate specific antigens.
2. To assess the impact of soy supplementation on estrogen receptor expression(ER).
3. To determine the impact of soy isoflavones on cell cycle regulation and associated gene expression.

• Study Type: Interventional
• Enrollment (Actual): 86
• Phase: Phase 3

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Kansas City, Missouri, United States, 64128
      • VA Medical Center, Kansas City MO

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Histologically proven prostate cancer.
• Surgical candidate for prostatectomy.
• During study period, must agree not to take new supplements.
• No concurrent chemotherapy, radiation or hormonal therapy.
• No history of prior allergy to soy based products.
• Must not have been taking soy supplements or soy isoflavones within 90 days prior to study enrollment.
• Must be able to safely be on study supplements for period of at least two weeks prior to scheduled prostatectomy.
• Must give written and informed consent in accordance with institutional and federal guidelines.

Exclusion Criteria:

During study period, must agree not to take new supplements.

• No concurrent chemotherapy, radiation or hormonal therapy.
• No history of prior allergy to soy based products.
• Must not have been taking soy supplements or soy isoflavones within 90 days prior to study enrollment.
• Must be able to safely be on study supplements for period of at least two weeks prior to scheduled

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Arm Placebo; Placebo	Drug: Placebo; Placebo will consist of a capsule without the soy protein added to be taken for 2-4 weeks until surgery to remove the prostate or start of radiation treatment. Patient will receive 4 capsules twice a day (8 capsules) daily to be taken with water or juice (except grapefruit juice).; Other Names: No other name
Experimental: Arm Soy Supplement; Soy Supplement	Drug: Soy Supplement; Soy protein supplement will be taken for 2-4 weeks until surgery to remove the prostate or start of radiation treatment. Patient will receive 4 capsules twice a day (8 capsules) daily to be taken with water or juice (except grapefruit juice).; Other Names: Fla-vien

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of Soy Isoflavones on Serum Testosterone Levels.	Total testosterone (ng/ml) serum levels were measured at the time of enrollment(baseline), after two weeks on soy supplement(time point 1), and just prior to prostatectomy (time point 2). All patients must have completed at least two week of soy supplement or placebo and time point 3 varied depending on date of planned prostatectomy. Results were analyzed and are reported at the two week time period, comparing between patients receiving soy supplement or placebo.	Two weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of Soy Isoflavones on Estrogen Receptor Status	Samples of the prostate cancer tissue (paraffin embedded) were sectioned and placed on a glass slide. Using immunohistochemistry and an estrogen receptor antibody, sections were stained and assess to determine the extent of estrogen receptor expression. Patients in the soy supplement arm's samples results were compared to placebo arm results.	Two weeks
Molecular Effects of Soy Supplementation Compared to Placebo.	Using a tissue microarray targeting the cell cycle, selected fresh prostate cancer samples were evaluated in patients in the soy supplement arm compared to the placebo arm.	One year

Collaborators and Investigators

• Sponsor: VA Office of Research and Development
• Investigators: Principal Investigator: Peter Vanveldhuizen, MD, VA Medical Center, Kansas City MO

Publications and helpful links

General Publications

• Hamilton-Reeves JM, Banerjee S, Banerjee SK, Holzbeierlein JM, Thrasher JB, Kambhampati S, Keighley J, Van Veldhuizen P. Short-term soy isoflavone intervention in patients with localized prostate cancer: a randomized, double-blind, placebo-controlled trial. PLoS One. 2013 Jul 12;8(7):e68331. doi: 10.1371/journal.pone.0068331. Print 2013.

Study record dates

Study Major Dates

• Study Start: September 1, 2005
• Primary Completion (Actual): April 1, 2009
• Study Completion (Actual): October 1, 2009

Study Registration Dates

• First Submitted: November 15, 2005
• First Submitted That Met QC Criteria: November 15, 2005
• First Posted (Estimate): November 17, 2005

Study Record Updates

• Last Update Posted (Actual): June 18, 2019
• Last Update Submitted That Met QC Criteria: June 6, 2019
• Last Verified: June 1, 2019

More Information

Terms related to this study

• Keywords: Isoflavones; Estrogen Receptor; Prostate Neoplasm; Soy Supplementation
• Additional Relevant MeSH Terms: Neoplasms; Urogenital Neoplasms; Neoplasms by Site; Genital Neoplasms, Male; Prostatic Diseases; Prostatic Neoplasms
• Other Study ID Numbers: CLIN-006-05S