Vitamin E succinate induced apoptosis of MDA-MB-435 human breast cancer cells

Objective:To investigate the growth inhibition and apoptosis induction effect of vitamin E succinate (VES) on MDA-MB-435 human breast cancer cells and to analyze the changes of Fas expression in this process. Methods:MDA-MB-435 human breast cancer cells were treated with VES at concentrations of 5μg/mL, 10μg/mL, and 20 μg/mL for 12, 24, and 48 h, respectively. The inhibitory effect of VES on cell proliferation was measured with MTT assay. Cell cycle and cell surface Fas expression were analyzed by flow cytometry. Apoptotic index was measured by TUNEL method. Fas protein level was detected by Western blotting assay. Results:VES had significant inhibitory effect on the growth of MDA-MB-435 human breast cancer cells. The inhibitory effect was in a time- and dose-dependent manner. Flow cytometry analysis showed that the apoptotic rate rose from 1.5% to 13.1%,20.2%,and 46.5% after treatment with VES for 48 h at the concentrations of 5μg/mL,10μg/mL,and 20μg/mL,respectively. Both apoptotic index and Fas expression of MDA-MB-435 cells increased after the treatment with VES. Apoptotic index rose from 1.1±0.4 to 10.8±1.0,30.4±2.7,and 51.4±4.7 after VES treatment. Fas protein level increased 1.3, 1.9, and 4.3 folds, respectively. The mean fluorescence intensity of Fas on cell surface rose from 46.2 to 59.66, 84.54, and 103.41. Conclusion:VES had significant growth inhibition and apoptosis induction effect on MDA-MB-435 estrogen receptor-negative breast cancer cells. The mechanism involved up-regulation of Fas on the surface of cancer cells.