Selenomethionine in Treating Patients Undergoing Surgery or Internal Radiation Therapy for Stage I or Stage II Prostate Cancer
RATIONALE: Selenomethionine may slow the growth of prostate cancer. Giving selenomethionine before surgery or internal radiation therapy may be an effective treatment for prostate cancer.
PURPOSE: This randomized phase II trial is studying how well selenomethionine works in treating patients undergoing surgery or internal radiation therapy for stage I or stage II prostate cancer.
Dietary Supplement: selenomethionine
|Study Design:||Allocation: Randomized
Primary Purpose: Treatment
|Official Title:||A Randomized, Double Blind, Placebo Controlled Clinical Trial of Supplementation of L-Selenomethionine in Patients With Prostate Cancer Prior to Prostatectomy or Brachytherapy (Se Pre-Prostatectomy/Pre-Brachytherapy Trial)|
- Quantity of androgen receptor message expression
- Expression of prostate-specific antigen, kallikrein 2, cell division cycle 6, and dehydrocholesterol reductase 24
- Expression of haptic nuclear factor 3-alpha
- Variation in thiol methyltransferase phenotype
|Study Start Date:||August 2008|
|Estimated Primary Completion Date:||June 2012 (Final data collection date for primary outcome measure)|
Experimental: Arm I
Patients receive oral selenomethionine once daily for 8-9 weeks.
Dietary Supplement: selenomethionine
Placebo Comparator: Arm II
Patients receive oral placebo once daily for 8-9 weeks.
- To investigate the down-regulation of the androgen receptor using tissue samples from patients with stage I or II prostate cancer treated with selenomethionine for 8-9 weeks prior to undergoing prostatectomy or brachytherapy.
- To evaluate the down regulation of a number of genes regulated by the androgen receptor (i.e., prostate-specific antigen, kallikrein 2, cell division cycle 6, and dehydrocholesterol reductase 24) using tissue samples from these patients.
- To evaluate the down-regulation of haptic nuclear factor 3-alpha using tissue samples from these patients.
- To evaluate whether the thiol methyltransferase phenotype modifies the prostatic response to short-term selenomethionine supplementation in these patients.
- To use quantitative nuclear morphometry to index cellular abnormality in tissue samples as measured by nuclear texture (e.g., total optical density, nuclear area, mean nuclear density, and optical heterogeneity).
OUTLINE: Patients are stratified according to planned treatment (brachytherapy vs prostatectomy). Patients are randomized to 1 of 2 treatment arms.
- Arm I: Patients receive oral selenomethionine once daily for 8-9 weeks. Patients then undergo prostatectomy or brachytherapy.
- Arm II: Patients receive oral placebo once daily for 8-9 weeks. Patients then undergo prostatectomy or brachytherapy.
Blood samples are collected at baseline and on the day of prostatectomy or brachytherapy. Samples are analyzed for selenium accumulation by atomic absorption spectrophotometry. Additional blood samples are stored for future analysis of alpha tocopherol, lycopene, and other vitamin levels, as well as oxidative stress biomarkers. Selenium accumulation is also evaluated in toenail samples at baseline to assess long-term selenium status. Prostate tissue samples are obtained during prostatectomy or brachytherapy and analyzed for RNA and expression of selenium-linked biomarkers (e.g., androgen receptor, prostate-specific antigen, kallikrein 2, cell division cycle 6, dehydrocholesterol reductase 24, and haptic nuclear factor 3 alpha) by quantitative reverse transcription (RT)-PCR. Biomarker expression is compared in both prostatectomy and brachytherapy specimens.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00736164
|Principal Investigator:||James L. Mohler, MD||Roswell Park Cancer Institute|