WEST LAFAYETTE, Indiana,
December 15, 2004 (ENS): The form of vitamin E found in
sesame seeds, walnuts and pecans - but not in most manufactured
nutritional supplements - might halt the growth of prostate and
lung cancer cells, researchers at Purdue University have found.
A team led by Qing Jiang has found that gamma-tocopherol, which
occurs naturally in walnuts, pecans, sesame seeds, and in corn and
sesame oils, inhibits the proliferation of human prostate and lung
cancer cells cultured in a lab.
The vitamin's presence interrupts the synthesis of fatty molecules
called sphingolipids, which are components of cell membranes. Healthy
human prostate cells are unaffected.
"This is the first time gamma-tocopherol has been shown to
induce death in lab-grown human cancer cells while leaving healthy
cells alone," said Jiang, who is an assistant professor of
foods and nutrition in the College of Consumer and Family Sciences.
"This could be wonderful news for cancer patients if the effect
can be reproduced in animal models. But because most nutritional
supplements contain only alpha-tocopherol, a different form of vitamin
E that alone does not have these anticancer properties, it may be
better to supplement the diet with mixed forms of vitamin E. The
study shows that the anticancer effect is enhanced when mixed forms
Jiang's research appears in the current online edition of the scientific
journal "Proceedings of the National Academy of Sciences."
It was funded in part by the National Institutes of Health.
Jiang said the next step for her research team will be testing
the effect of gamma-tocopherol and mixed forms of vitamin E on animal
"Although this discovery is promising, we do not yet know
whether gamma-tocopherol has any effect on cancer in living creatures,"
she said. "We hope that future research not only will clarify
whether gamma-tocopherol could have applications in human cancer
treatment, but also will show how we might supplement the body with
the vitamin to prevent cancer from developing in the first place."