Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Vitamin E in plant seeds could halt prostate, lung cancer

15.12.2004


The form of vitamin E found in many plant seeds – but not in most manufactured nutritional supplements – might halt the growth of prostate and lung cancer cells, according to a Purdue University study.



A team led by Qing Jiang (pronounced "ching zhang") has found that gamma-tocopherol, which occurs naturally in walnuts, pecans, sesame seeds, and in corn and sesame oils, inhibits the proliferation of lab-cultured human prostate and lung cancer cells. The vitamin’s presence interrupts the synthesis of certain fatty molecules called sphingolipids, important components of cell membranes. However, the gamma-tocopherol leaves healthy human prostate cells unaffected, which could give it value as an anticancer agent.

"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 are used."


Jiang’s research appears in the current (week of Dec. 13) online edition of the scientific journal Proceedings of the National Academy of Sciences. She co-authored the paper with Jeffrey Wong, Henrik Fyrst, Julie D. Saba and Bruce N. Ames of the Children’s Hospital Oakland Research Institute in Oakland, Calif.

Scientists have been studying vitamin E for more than three-quarters of a century, but most efforts have focused largely on alpha-tocopherol, one of eight known forms in the vitamin’s family. Alpha-tocopherol was found early on to have the most beneficial effects on laboratory animals fed diets deficient in vitamin E, and also is the major form found in body tissues. For these reasons, it has been nearly the only form of the vitamin to be included in most manufactured nutritional supplements.

"Since then, alpha-tocopherol has justifiably earned a good reputation as an antioxidant, which helps to fight against damage caused by unwanted free radicals," Jiang said. "But its familiarity has perhaps attracted research away from the other seven forms of vitamin E, and since gamma-tocopherol is the vitamin’s most commonly occurring natural form in the American diet, I grew interested in it a few years ago."

In 2000 another study by Jiang and colleagues found that gamma-tocopherol inhibits inflammation, which had already been implicated in cancer development. They theorized that it might retard the progress of cancer and cardiovascular disease, and to test their hypothesis they exposed cultures of cancerous prostate and lung cells to the vitamin. Normal prostate epithelial cells were used as a control group.

"We discovered that as we increased the quantity of gamma-tocopherol, the cancer cells grew more slowly," Jiang said. "But the normal prostate cells were not affected and grew normally. This could indicate that the vitamin could be used to target lung and prostate cancer cells without the damaging side effects of chemotherapy."

The study also revealed that gamma-tocopherol caused cell death by interrupting sphingolipid synthesis.

"This is also a novel discovery," Jiang said. "Although there have been prior indications that some form of vitamin E may cause cell death in some mouse cell lines, we are the first to provide a mechanism for such an effect."

Gamma-tocopherol, though rarely available in vitamin pills, is nevertheless found in abundance in the typical American diet. Many nuts are rich in it, including walnuts and pecans, as are cooking oils such as corn and sesame oil.

Though Jiang said she would be cautious about using food sources to slow prostate or lung cancer’s progress in humans, she said that high-risk groups such as older men could benefit from supplementation – if carried out with prudence.

"Foods rich in gamma-tocopherol are also rich in fats, and some products bring other hazards as well," she said. "Corn oil, for example, is rich in linolic acid, which has been shown to promote certain types of cancer in some studies. But sesame seeds and pecans seem to be good all-around choices."

Jiang said the next step for her research team would be testing the effect of gamma-tocopherol and mixed forms of vitamin E on animal cancers.

"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. These questions will continue to direct our work."

This research was funded in part by the National Institutes of Health.

Chad Boutin | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>