Grape seed extract sensitizes human breast carcinoma cells to chemotherapy agents-induced growth inhibition and apoptotic death via cytochrome c release and caspase activation pathway.

5460 Grape seed extract (GSE) is one of the most commonly consumed dietary supplements in the United States because of its several health benefits. Several studies in recent years have also shown its pre-clinical efficacy as an anti-cancer agent against several epithelial cancers including breast. Since cancer patients often also consume dietary supplements while on chemotherapy, here we investigated the anti-cancer effects of GSE in combination with taxotere, cisplatin and carboplatin employing estrogen receptor-negative MDA-MB468 and MDA-MB231 human breast carcinoma cells as a model system. Based on cell growth inhibitory and death effects obtained for all four agents, several combinations of GSE (25-100 microgram/ml) with taxotere (1-10 nM) or cisplatin (0.2-2 microgram/ml) or carboplatin (2-20 microgram/ml) were next assessed for their synergistic, additive and/or antagonistic efficacy for cell growth inhibition and death. The strongest synergistic effects combination index (CI)