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Background: Colorectal cancer is one of the most important and most common fatal types of cancer in the world. Identifying new agents which individually or in combination with other agents induce apoptosis in tumor cells is surely of great significance in treatment of colon cancer. The aim of the present study was to assess the effectiveness of applying lovastatin and α-tocopherol individually or in combination with each other in the induction of apoptosis in human colorectal cancer cells. Materials and Methods: In this trial, HT29 cells were exposed to various concenterations of lovastatin (5, 10, and 20 μmol) and/or alpha tocopherol (10, 20, and 25, and 30 μmol). After cell count, these cells were examined through trypan blue method and DNA fragmentation technique. Results: The findings of DNA fragmentation technique showed that each of the two drugs could induce apoptosis at all of the given concentrations. In the combination of 10 μmol concentration of lovastatin and 5 and 10 μmol concentrations of α-tocopherol, induction of apoptosis was not observed. Conclusion: Based on the extensive effects of statins, the concentration of lovastatin is seen as determining in its apoptosis function, and its combination with tocopheroles in high concentrations, by inducing apoptosis, can provide novel effective strategies for prevention of human colorectal cancer.

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  Background: Alpha-tocopherol, as a strong antioxidant, plays an important role in testraining free radicals. The aim of this study was to investigate the effect of Alpha-tocopherol on cell proliferation and restraining apoptosis in rat bone marrow mesenchymal stem cells.

  Materials and Methods: In this research study, the rat bone marrow mesenchymal stem cells were extracted under sterile conditions using flashing-out method. At the end of the third passage, cells were divided into groups of control and Alpha-tocopherol with doses of 15 and 25 µM and were treated in the osteogenic media cell medium containing 10% fetal bovine serum, 10 mM β-glycerol phosphate, 10 nM dexamethasone and 50 µg/ml ascorbic 3-phosphate] for a period of 21 days. Then, cell proliferation, DNA damage, expression of Bcl-2 and Bax genes and the morphologic changes of the cells were investigated during the procedure of osteogenesis. Data were analyzed using one-way ANOVA and means difference was considered significant at p<0.05.

  Results: Cell proliferation, the size of nuclei diameter and expression of anti-apoptotic Bcl-2 gene showed a significant increase in mesenchymel stem cells treated with Alpha-tocopherol (p<0.05) in a dose dependent manner compared to the control cells. Also, cytoplasm extension was seen in the cells treated with Alpha-tocopherol, compared to the control group. Since Alpha-tocopherol causes a significant decrease in DNA damage and the expression of apoptotic Bax gene, compared to the control group, therefore it can suppress apoptosis in bone marrow mesenchymal stem cells, in a dose dependent manner .