| Breast cancer is a common cancer in women. The objective of this study was to investigate the effect of treatment by a dietary phytosterol, beta-sitosterol, and a common anti-breast cancer drug, tamoxifen, alone and in combination, on growth and ceramide metabolism in MDA-MB-231 and MCF-7 human breast cancer cells. Both cell lines exhibited cell growth inhibition with 16 muM beta-sitosterol treatment. Only MCF-7 cell growth was inhibited with 1 muM tamoxifen treatment. Growth inhibition was observed after combination treatments in both cell lines. However, a difference in this regard depended on the concentration of these compounds and cell type. Ceramide metabolism was increased after the combination treatments. Serine palmitoyltransferase activity was mainly affected by 16 muM beta-sitosterol while tamoxifen inhibited ceramide glycosylation. Taken together, these results suggest that a combination dietary/anti-cancer drug treatment regimen may be beneficial in the management of breast cancer patients. |
