Effect of Saw Palmetto on the Development and Progression of Prostate Carcinoma in TRAMP Mice

Abstract

Abstract : We established a breeding colony for TRAMP (transgenic adenocarcinoma of the mouse prostate) mice in order to study the effects of saw palmetto berry extract (SPE) on the spontaneous development of prostate cancer. Four week old mice have been assigned to one of two study groups: 1) short-term (8 week) SPE treatment, and 2) long-term (20 week) SPE treatment. There were 4 different cohorts within each study group: WT control diet, TRAMP control diet, TRAMP low dose SPE diet (50 mg/kg) and TRAMP high dose SPE diet (300 mg/kg). The study was statistically empowered at the P=0.05 levels and consisted of ~17 mice/cohort. We found that SPE was well tolerated by mice having no adverse effects on body or organ weights. Although SPE did not affect prostate weight at either the 12 or 24 week time points, high dose SPE treatment resulted in a significantly decreased percentage of differentiated cancer and increased PIN compared to controls. These results are the first to suggest that SPE can delay prostate cancer tumor progression in TRAMP mice. We are currently evaluating the cellular mechanism by which SPE exerts this effect.