Gamma Tocopherol and Lovastatin Additively Induced Apoptosis in Human Colorectal Carcinoma Cell Line (HT29)

Background: Programmed cell death (apoptosis) is a physiological process needed to remove unwanted or damaged cells. It has been hypothesized that any failure of programmed cell death leads to the development of neoplasm. Identifying new agents which induce apoptosis in tumor cells is of great significance in treatment of neo­ plasms. Numerous studies suggest that exposure of trumor cells to statins and gamma tocopherol can lead to cell death. Objectives: The aim of this study was to evaluate the cell death induced by gamma to-copherol and lovastatin in human colorectal carcinoma cell line (HT29) using flow cytometry. Materials and Methods: HT29 cells were grown in DMEM medium, exposed to different concentrations of lovastatin (10,20,40,100?M ) and gamma tocopherol (25,50,100,200?M) for 48 and 72 hours, individually and in combination (100?M both, 48 h). Phenotype of apoptosis was determined by means of flow cytometry. Results: All Concentrations of lovastatin (10, 20, 40, 100 ?M) and gamma tocopherol (25, 50, 100, 200 ?M) induced an apoptotic response in HT29 cells .In combination, a significant increase in apoptosis phenotype was also demonstrated (P < 0.05). Conclusions: This study showed that lovastatin when combined with gamma tocopherol, could induce apoptosis in HT29 cells more potently than each agent alone, which uncovers the significance of targeting the proliferative signaling in different points of the pathway.