Positive Health Online

Abstract

ANDERSON and colleagues, School of Biological Sciences/C0900, University of Texas at Austin, 78712, USA, have observed a differential response of human ovarian cancer cells to induction of programmed cell death (apoptosis) by vitamin E succinate and the vitamin E analogue, alpha-TEA.

Background

A vitamin E derivative, vitamin E succinate, and a vitamin E analogue, alpha-TEA, induce various human tumour cells in culture to undergo apoptosis, but fail to do so in normal cells. Human ovarian and cervical cancer cell lines are exceptions to this, with alpha-TEA exhibiting greater apoptotic effects.

Methodology

Methods: In vitro study using cell lines in culture.

Results

Vitamin E succinate or alpha-TEA treatment of ovarian cancer cells (called cp70) with 5, 10, or 20 micrograms/ml for 3 days induced 5, 6, and 19% versus 9, 36, and 71% apoptosis, respectively. Colony formation data provide additional evidence that cp70 cells are more sensitive to growth inhibition by alpha-TEA than vitamin E succinate. Differences in stability of the two compounds were demonstrated in chemical analysis that showed alpha-TEA to remain intact, whereas vitamin E succinate was hydrolyzed. Pre-treatment of cp70 cells with an inhibitor of hydrolyzing enzymes before vitamin E succinate treatment resulted in increased levels of intact vitamin E succinate and apoptosis.

Conclusion

Taken together, these data show that alpha-TEA is a potent and stable pro-apoptotic agent for human ovarian tumour cells, whereas vitamin E succinate is less effective because it is being inactivated by endogenous enzymes.

References

Anderson K, Simmons-Menchaca M, Lawson KA, Atkinson J, Sanders BG, Kline K. Differential response of human ovarian cancer cells to induction of apoptosis by vitamin E Succinate and vitamin E analogue, alpha-TEA. Cancer Research 64(12): 4263-4269, Jun 15, 2004.