Background: The extract of Allium cepa Linn is commonly used as adjuvant food for cancer therapy. We assumed that it includes a potential source of anti-cancer properties.Methods: We investigated anti-cancer effects of polyphenols extracted from lyophilized A. cepa Linn (PEAL) in AGS human cancer cells.Results: PEAL inhibited cell growth in a dose-dependent manner. It was related to caspase-dependent apoptosis. We confirmed this finding with annexin V staining. PEAL up-regulated p53 expression, and subsequent Bax induction, down regulated Bcl-2 protein, anti-apoptotic protein. In addition, PEAL suppressed Akt activity and PEAL-induced apoptosis were significantly accentuated with Akt inhibitor (LY294002). Conclusions: Our data suggested that PEAL induce caspase-dependent apoptosis through mitochondrial pathway by up-regulating p53 protein, and subsequent Bax protein as well as by modulating Bcl-2 protein, and that PEAL induces caspase-dependent apoptosis at least in part through the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. This study provides evidence that PEAL might be useful for the treatment of cancer. ( In this study, we investigated the mechanisms of anticancer effects of PEAL on human AGS cells.
MATERIALS AND METHODS
Preparation of PEALPEAL isolated from the plants of A. cepa Linn which we bought from the market and 100 mg/mL concentration content was measured by propidium iodide (PI) staining.