Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Green tea and COX-2 inhibitors combine to slow growth of prostate cancer

05.03.2007
Drinking a nice warm cup of green tea has long been touted for its healthful benefits, both real and anecdotal. But now researchers have found that a component of green tea, combined with low doses of a COX-2 inhibitor, could slow the spread of human prostate cancer.

In the March 1 issue of Clinical Cancer Research, researchers from University of Wisconsin-Madison demonstrate that low doses of the COX-2 inhibitor celecoxib, administered with a green tea polyphenol called pigallocatechin-3-gallate (EGCG), can slow the growth of human prostate cancer. Their experiments were performed in cell cultures and in a mouse model for the disease.

“Celecoxib and green tea have a synergistic effect -- each triggering cellular pathways that, combined, are more powerful than either agent alone,” said Hasan Mukhtar, Ph.D., professor of dermatology at the University of Wisconsin and member of Wisconsin’s Paul Carbone Comprehensive Cancer Center. “We hope that a clinical trial could lead to a preventative treatment as simple as tea time.”

Previous research has linked the cyclooxygenase-2 enzyme, commonly known as COX-2, to many cancer types, including prostate cancer, said Mukhtar. Mukhtar and his colleagues have previously shown COX-2 inhibitors like celecoxib (known under the brand name Celebrex™) suppress prostate cancer in animal models. COX-2 inhibitors also have been shown to cause adverse cardiovascular effects when administered at high doses over long durations.

In 2004, Mukhtar and his colleagues demonstrated that green tea polyphenol EGCG has cancer-fighting abilities of its own. Their study, published in Cancer Research, showed that EGCG can modulate the insulin-like growth factor-1 (IGF-1)-driven molecular pathway in a mouse model for human prostate cancer, pushing the cells toward programmed cell death (apoptosis).

“We believed that COX-2 inhibitors may still prove beneficial if used in combination with complementary agents,” Mukhtar said. “Our studies showed that the additive effect of green tea enables us to utilize the cancer-fighting abilities of COX-2 inhibitors, but at lower, safer doses.”

In this latest research, Mukhtar and his colleagues looked at the effects of the two substances on cultured human prostate cancer cells. Alone, both EGCG and NS-398, a COX-2 inhibitor similar to celecoxib, demonstrated the ability to slow cancer cell growth and limit the presence of known cancer-promoting proteins within the cell samples. Together, EGCG and NS-398 suppressed cell growth by an additional 15 to 28 percent.

The researchers repeated the experiment in mouse models of prostate cancer, using celecoxib and an oral suspension of the decaffeinated green tea polyphenol. By using pharmacy-grade celecoxib and actual tea, they had hoped to replicate real-life conditions. “The idea is that it would be easier to get people to drink green tea than it would be to take an additional dietary supplement,” Mukhtar said.

In mice that were not treated with either substance, the tumor volume averaged 1,300 cubic millimeters, whereas mice given either the tea or celecoxib had tumors averaging 835 cubic millimeters and 650 cubic millimeters, respectively. Tumors taken from mice given both agents, however, measured on average a volume of 350 cubic millimeters.

In parallel to tumor growth inhibition, mice that received a combination of green tea and celecoxib registered a greater decrease in prostate specific antigen (PSA) levels compared to that in celecoxib alone or green tea alone treated animals. PSA is a protein produced by the cells of the prostate and is used as a marker for detection and progression of prostate cancer. These results, combined with a marked decrease in the presence of cancer-promoting proteins, offered clear indications that green tea and celecoxib, combined, could be useful in slowing prostate cancer growth, Mukhtar said.

“Prostate cancer typically arises from more than one defect in the cellular mechanics, which means that a single therapeutic might not work fighting a particular cancer long-term,” Mukhtar said. “If tests in human trials replicate these results, we could see a powerful combined therapy that is both simple to administer and relatively cost effective.”

Greg Lester | EurekAlert!
Further information:
http://www.aacr.org

More articles from Health and Medicine:

nachricht Hot cars can hit deadly temperatures in as little as one hour
24.05.2018 | Arizona State University

nachricht 3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>