BACKGROUND:
Tamoxifen is widely used for the treatment of breast cancer. Pterostilbene, a bioavailable stilbenoid found in blueberries, has been found to inhibit breast cancer growth in vitro. It was hypothesized that combining pterostilbene with tamoxifen would produce additive effects on estrogen receptor-positive breast cancer cells.
METHODS:
Two estrogen receptor-positive breast cancer cell lines, MCF7 and ZR-751, were pretreated with graduated doses of pterostilbene for 24 hours, followed by 5 μmol/L tamoxifen. MTT proliferation assays and Cell Death Detection ELISA(PLUS) tests evaluated cell viability and apoptosis.
RESULTS:
MCF7 cells showed inhibition (10 and 20 μmol/L, P < .001; 30 μmol/L, P < .05) at all time points when combined with tamoxifen. ZR-751 cells showed additive reductions in cell viability (P < .001). Cell Death Detection ELISA(PLUS) indicated increased apoptosis (P < .01).
CONCLUSIONS:
Pterostilbene shows an additive inhibitory effect on breast cancer cells when combined with tamoxifen, most likely from augmented cancer cell apoptosis.
Copyright © 2010 Elsevier Inc. All rights reserved.