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Vitamin E promotes breast cancer cell proliferation by reducing ROS production and p53 expression.

OBJECTIVE
The role of antioxidant in cancer cell proliferation is still controversial. This study aimed to explore the effects of antioxidant vitamin E on the proliferation of breast cancer cells and the possible underlying mechanisms.


MATERIALS AND METHODS
Orthotopic breast cancer model was established by inoculating MCF7 cells in mice and in vitro MCF7 culture system. CM-H2DCFDA fluorescence probe and Western blot analysis were used to detect ROS changes and p53 expression. p53 knockdown in MCF7 cells by siRNA transfection was also used to determine the combination effect of vitamin E and p53 on MCF7 cell proliferation.


RESULTS
Vitamin E supplement in the chow significantly accelerated breast cancer cell growth in vivo. ROS level and p53 expression were decreased in tumor tissues. Water-solvable vitamin E Trolox significantly promoted MCF7 cell proliferation in vitro, while reducing intracellular ROS level and p53 expression. p53 knowdown by p53-siRNA transfection inMCF7 cells significantly reduced p53 expression and increased MCF7 cell proliferation.


CONCLUSIONS
Vitamin E accelerated breast cancer growth by reducing ROS production and p53 expression.