An interesting study shows the inhibitory effects of Saw palmetto berry extract on prostate cancer cell culture (Cell Biol Int 2001;25(11):1117-24. Authors: Goldmann W H, Sharma A L, Currier S J, Johnston P D, Rana A, Sharma C P.; Boston BioProducts Inc., Ashland, MA 01721, USA.)

Saw palmetto berry extract inhibits cell growth and Cox-2 expression in prostatic cancer cells.

The cytotoxicity of a commonly used material to alleviate the symptoms of benign prostatic hyperplasia (BPH), Saw Palmetto Berry Extract (SPBE), was examined as neat oil using a set of prostatic cell lines; 267B-1, BRFF-41T and LNCaP. Proliferation of these prostatic derived cell lines is inhibited to different degrees when dosed for 3 days with SPBE. The amount of SPBE required to inhibit 50% growth (IC50) of these cell lines was 20-30 nl equivalents of SPBE per ml of medium for cell lines 267B-1 and BRFF-41T and approximately 10-fold more for the LNCaP cell line. The effect of [Saw palmetto berry extract] dosing on these cell lines is not irreversible, since a 30 min treatment with SPBE at an IC50 concentration does not inhibit their growth. Normal prostate cells were inhibited by 20-25% when grown in the presence of 200 nl [Saw palmetto berry extract] equivalent per ml media. Growth of other non-prostatic cancer cell lines, i.e. Jurkat and HT-29, was affected by approx. 50% and 40%, respectively. When LNCaP cells were grown in the presence of dihydrotestosterone and [Saw palmetto berry extract], the IC50 concentration decreased significantly compared to LNCaP cells grown in the presence of serum and [Saw palmetto berry extract]. Reduced cellular growth after [Saw palmetto berry extract] treatment of these cell lines may relate to decreased expression of Cox-2 and may be due to changes observed in the expression of Bcl-2. Expression of Cox-1 under similar conditions is not affected because of its constitutive expression. Since increased Cox-2 expression is associated with an increased incidence of prostate cancer, and decrease in its expression by [Saw palmetto berry extract] would provide a basis for further investigation of its use against BPH and in prostatic cancer chemoprevention.