Protein Helps Vitamin E Fight Cancer

TUESDAY, Nov. 1, 2005 (HealthDay News) -- Researchers say they've identified a protein that suppresses prostate cancer while enhancing the cancer-fighting effects of vitamin E.

The protein -- alpha tocopherol associated protein (TAP) -- disrupts an important signaling pathway in prostate cancer cells and, by doing so, suppresses prostate cancer growth. The protein also assists in the retention of vitamin E in prostate cancer cells and increases the vitamin's effect in limiting cancer cell proliferation.

Researchers at the University of Rochester Medical Center also found TAP expression levels to be much lower in the cancer-afflicted prostate vs. the normal prostate. This suggests that high TAP expression in prostate cells may play a role in normal prostate development and vitamin E-related functions.

The study appears in the Nov. 1 issue of the journal Cancer Research and is the first to describe the role of TAP in prostate cancer.

According to the researchers, restoring TAP levels in prostate cancer patients might provide a new method of treatment. However, much more research is required to determine if this is even possible. TAP does have immediate potential as a new prognostic marker for prostate cancer, however.

"If research continues to show the important role of TAP, we could use TAP expression levels to better assess and predict the aggressiveness of the cancer. We may be able to use TAP levels to predict whether a patient will respond to treatment," Dr. Edward M. Messing, chair of urology at the University of Rochester Medical Center, said in a prepared statement.

More information

The American Cancer Society has more about prostate cancer.