Tea Polyphenols May Inhibit Prostate Cancer Progression
Study finds Polyphenon E capsules reduce serum levels of several prostate cancer biomarkers
FRIDAY, June 19 (HealthDay News) -- Taking daily doses of green tea polyphenols in capsule form may someday have a role in the prevention and treatment of prostate cancer, according to a study published online June 19 in Cancer Prevention Research.
Jerry McLarty, Ph.D., of Louisiana State University Health Sciences Center in Shreveport, and colleagues recruited a cohort of 26 patients with positive biopsies for prostate cancer who were scheduled for radical prostatectomy. The patients were put on daily doses of 1.3 grams of green tea polyphenols in the form of Polyphenon E capsules. The therapy lasted a median of 34.5 days for 25 of 26 patients and was stopped the day of the surgery. Serum was tested for hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), and prostate-specific antigen (PSA). Liver function was also monitored.
The researchers found that serum levels of HGF, VEGF, PSA, IGF-I, IGFBP-3, and the IGF-I/IGFBP-3 ratio all decreased significantly in the treated patients, while liver function remained normal.
"Our results show a significant reduction in serum levels of PSA, HGF, and VEGF in men with prostate cancer after brief treatment with EGCG (Polyphenon E), with no elevation of liver enzymes. These findings support a potential role for Polyphenon E in the treatment or prevention of prostate cancer," the authors conclude.