May 22, 2006

Scientists turn vitamin E into super cancer killer

A report published in the April 28 issue of the Journal of Biological Chemistry detailed the discovery of researchers at The Ohio State University Comprehensive Cancer Center-Arthur G. James Center Hospital and Richard J. Solove Research Institute that slightly modifying alpha-tocopherol (vitamin E) succinate makes its cancer killing ability five to ten times greater than that of the vitamin in its normal state. Vitamin E succinate has already been shown to induce programmed cell death in cancer cells, but researchers had been unaware of how it causes this to occur.

Professor of pharmacy and internal medicine Ching-Shih Chen and his colleagues discovered that vitamin E succinate fights cancer by blocking Bcl-xL, a protein made by healthy cells that is frequently elevated in cancer cells and protects them from dying. They found that vitamin E succinate disables Bcl-xL by lodging in groove in its structure; however, the long tail of the vitamin keeps it from fitting tightly and working more effectively.

“Once we identified how the agent and the protein interact, we asked how we could improve that interaction,” Dr Chen stated. His team found that by shortening the vitamin E molecule's tail, its cancer-destroying activity in prostate cancer cell cultures increased five to tenfold.

"Our findings could lead to a potent chemopreventive agent that has both strong anticancer and antioxidant properties,” Dr Chen speculated. “Such an agent might help reduce the risk of prostate, colon and other cancers.”

“Overall, out findings are proof of the principle that this drug can kill cancer cells very effectively but does very little damage to healthy cells,” he concluded.