Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study Shows How Vitamin E Can Help Prevent Cancer

15.03.2013
Researchers have identified an elusive anti-cancer property of vitamin E that has long been presumed to exist, but difficult to find.

Many animal studies have suggested that vitamin E could prevent cancer, but human clinical trials following up on those findings have not shown the same benefits.

In this new work, researchers showed in prostate cancer cells that one form of vitamin E inhibits the activation of an enzyme that is essential for cancer cell survival. The loss of the enzyme, called Akt, led to tumor cell death. The vitamin had no negative effect on normal cells.

“This is the first demonstration of a unique mechanism of how vitamin E can have some benefit in terms of cancer prevention and treatment,” said lead author Ching-Shih Chen, professor of medicinal chemistry and pharmacognosy at The Ohio State University and an investigator in Ohio State’s Comprehensive Cancer Center.

The study appears in the March 19, 2013, issue of the journal Science Signaling.

Chen cautioned that taking a typical vitamin E supplement won’t offer this benefit for at least two reasons: The most affordable supplements are synthetic and based predominantly on a form of the vitamin that did not fight cancer as effectively in this study, and the human body can’t absorb the high doses that appear to be required to achieve the anti-cancer effect.

“Our goal is to develop a safe pill at the right dose that people could take every day for cancer prevention. It takes time to optimize the formulation and the dose,” he said.

Chen has filed an invention disclosure with the university, and Ohio State has filed a patent application for the agent.

Vitamin E occurs in numerous forms based on their chemical structure, and the most commonly known form belongs to a variety called tocopherols. In this study, researchers showed that, of the tocopherols tested, the gamma form of tocopherol was the most potent anti-cancer form of the vitamin.

The scientists manipulated the structure of that vitamin E molecule and found that the effectiveness of this new agent they created was 20-fold higher than the vitamin itself in cells. In experiments in mice, this agent reduced the size of prostate cancer tumors.

These findings suggest that an agent based on the chemical structure of one form of vitamin E could help prevent and treat numerous types of cancer – particularly those associated with a mutation in the PTEN gene, a fairly common cancer-related genetic defect that keeps Akt active.

The researchers began the work with both alpha and gamma forms of the vitamin E molecule. Both inhibited the enzyme called Akt in very targeted ways, but the gamma structure emerged as the more powerful form of the vitamin.

In effect, the vitamin halted Akt activation by attracting Akt and another protein, called PHLPP1, to the same region of a cell where the vitamin was absorbed: the fat-rich cell membrane. PHLPP1, a tumor suppressor, then launched a chemical reaction that inactivated Akt, rendering it unable to keep cancer cells alive.

“This is a new finding. We have been taking vitamin E for years but nobody really knew about this particular anti-cancer mechanism,” Chen said.

The gamma form was most effective because its chemical shape allowed it to attach to Akt in the most precise way to shut off the enzyme.

Because of how the various molecules interacted on the cell membrane, the scientists predicted that shortening a string of chemical groups dangling from the main body, or head group, of the gamma-tocopherol molecule would make those relationships even stronger. They lopped off about 60 percent of this side chain and tested the effects of the new agent in the prostate cancer cells.

“By reducing two-thirds of the chain, the molecule had a 20 times more potent anti-tumor effect, while retaining the integrity of vitamin E’s head group,” Chen said. This manipulation enhanced the anti-tumor potency of the molecule by changing its interaction with the cell membrane, so that the head group was more accessible to Akt and PHLPP1.

When mice with tumors created by these two prostate cancer cell lines were injected with the agent, the treatment suppressed tumor growth when compared to a placebo, which had no effect on tumor size. Chemical analysis of the treated tumors showed that the Akt enzyme signal was suppressed, confirming the effects were the same in animals as they had been in cell cultures.

The animal study also suggested the experimental agent was not toxic. Chen’s lab is continuing to work on improvements to the molecule.

This work was supported by the National Institutes of Health.

Co-authors include Po-Hsien Huang, Hsiao-Ching Chuang, Chih-Chien Chou, Huiling Wang, Su-Lin Lee, Hsiao-Ching Yang, Hao-Chieh Chiu, Naval Kapuriya, Dasheng Wang and Samuel Kulp of the Division of Medicinal Chemistry and Pharmacognosy at Ohio State. Huang and Chen also are affiliated with National Cheng-Kung University, Yang with Fu-Jen Catholic University, and Chiu with National Taiwan University, all in Taiwan; and Kapuriya with Saurashtra University in Gujarat, India.

Contact: Ching-Shih Chen, (614) 688-4008; chen@pharmacy.ohio-state.edu
(Email is the best way to contact Chen.)
Written by Emily Caldwell, (614) 292-8310; Caldwell.151@osu.edu

Ching-Shih Chen | EurekAlert!
Further information:
http://www.osu.edu

More articles from Studies and Analyses:

nachricht Obstructing the ‘inner eye’
07.07.2017 | Friedrich-Schiller-Universität Jena

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Ultrathin device harvests electricity from human motion

24.07.2017 | Power and Electrical Engineering

Scientists announce the quest for high-index materials

24.07.2017 | Materials Sciences

ADIR Project: Lasers Recover Valuable Materials

24.07.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>