Researchers Report How Vitamin E May Fight Prostate Cancer

ROCHESTER, N.Y.--Researchers from the University of Rochester reported they may know how vitamin E may benefit prostate cancer in a study that appears in the May 28 Proceedings of the National Academy of Sciences (99, 11:7408-13, 2002) (www.pnas.org).

Using vitamin E in the form of alpha-tocopheryl succinate, researchers found that the nutrient suppressed the expression of prostate-specific antigen, a marker for the progression of prostate cancer. They also found that vitamin E suppresses androgen receptor expression through transcriptional (reducing the amount of messenger RNA available to androgen receptor expression) and post-transcriptional modulation (directly impacting androgen receptor expression).

In terms of cell growth, vitamin E inhibited the growth of the prostate cancer cells, LNCaP. Comparatively, the pharmaceutical anti-androgen--hydroxyflutamide--commonly used in prostate cancer patients was shown to only slightly inhibit the growth of LNCaP cells. The researchers noted that, interestingly, simultaneous administration of the drug with vitamin E resulted in a more significant inhibitory effect on LNCaP cell growth.

The study's authors reported this finding may help establish new therapies in preventing and treating prostate cancer. "As we have found that vitamin E reduced the amount of androgen receptor, a key factor for the progression of prostate cancer, this could be the base to concert different therapy strategies," said Shuyuan Yeh, a study author and an assistant professor in the department of urology and pathology at the university. "For example, anti-androgen will prevent androgen's bind on androgen receptor and vitamin E would reduce the amount of androgen receptor. The combination of anti-androgen and vitamin E would possibly elicit better therapy effects.

"Overall, we are confident to say [alpha-tocopheryl succinate] is a safe and promising dietary supplement for cancer prevention," Yeh added.