This randomized pilot phase I trial will evaluate if quercetin enhances the uptake of green tea polyphenols in the prostate tissue of men taking green tea extract and undergoing radical prostatectomy. Side effects of green tea extract and quercetin in combination with green tea extract will also be evaluated. In preclinical studies, green tea polyphenols have anticancer and cancer preventative effects in a number of malignancies. Likewise, in preclinical studies quercetin was found to enhance the anticancer effects of green tea. This trial is designed to translate these findings forward in a short-term human intervention trial.
PRIMARY OBJECTIVES: I. To investigate the prostate tissue concentration of epigallocatechin gallate (EGCG), epicatechin gallate (ECG) and quercetin and their methylated metabolites in men scheduled for prostatectomy and consuming green tea (GT)extract (N=15) or GTextract with quercetin (N=15) for 3 weeks prior to prostatectomy. II. To determine the concentration of EGCG, ECG, epigallocatechin (EGC), epicatechin (EC) and quercetin and the methylated metabolites in plasma collected before (T=0) and two hours (T=2) after the intake of the morning dose of GTextract and placebo or GTextract with quercetin during the third week of intervention. III. To determine the effect of GTextract/quercetin intervention on reducing the enzyme activity and protein and gene expression of catechol-O-methyltransferase (COMT) and deoxyribonucleic (DNA) (cytosine-5) methyltransferase 1 (DNMT1) as well as protein and gene expression of multidrug resistance transport protein 1 (MRP1) in prostate tissue collected in specific aim 1 and COMT activity in erythrocytes from blood collected at baseline and week 3. IV. To determine the inter-individual variation in genotype of COMT in buffy coat DNA. OUTLINE: Patients are randomized to 1 of 2 treatment arms. ARM I: Patients receive GT extract orally (PO) twice daily (BID) and quercetin PO BID for 3-6 weeks before undergoing prostatectomy. ARM II: Patients receive GT extract PO BID and placebo PO BID for 3-6 weeks before undergoing prostatectomy.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
DOUBLE
Enrollment
32
Given PO
Given PO
Given PO
Undergo prostatectomy
Correlative studies
Veterans Administration Los Angeles Healthcare System
Los Angeles, California, United States
Jonsson Comprehensive Cancer Center
Los Angeles, California, United States
Green tea polyphenols, quercetin and their metabolite concentration in blood and prostate tissue
Means and standard deviation will be calculated and the statistical difference between treatment with GTextract + quercetin compared to GTextract + placebo will be determined using Student's t-test computed by one-way analysis of variance models.
Time frame: On the day of surgery
Protein and gene expression of COMT in prostate tissue
Time frame: Day of surgery
Protein and gene expression of DNMT1 in prostate tissue
Time frame: Day of surgery
Protein and gene expression of MRP1 in prostate tissue
Time frame: Day of surgery
COMT activity in red blood cells
Time frame: Week 3
Genotype of COMT (high [H]/H, low [L]/L or H/L)
Gene-association analyses will be conducted for COMT polymorphic variants within each intervention group using SAS Genetics, version 9.1
Time frame: Week 3
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