Featured Research

from universities, journals, and other organizations

Dioxin-like chemical messenger makes brain tumors more aggressive

Date:
October 7, 2011
Source:
University Hospital Heidelberg
Summary:
Researchers have discovered a new metabolic pathway which makes malignant brain tumors more aggressive and weakens patients' immune systems. Using drugs to inhibit this metabolic pathway is a new approach in cancer treatment.

A research alliance of Heidelberg University Hospital and the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), jointly with colleagues of the Helmholtz Center for Environmental Research in Leipzig, has discovered a new metabolic pathway which makes malignant brain tumors (gliomas) more aggressive and weakens patients' immune systems. Using drugs to inhibit this metabolic pathway is a new approach in cancer treatment.

Related Articles


The group's results have been published in the journal Nature.

Glioma is the most frequent and most malignant brain tumor in adults. In Germany, about 4,500 people are newly diagnosed with glioma every year. About 75 percent of such tumors are considered particularly aggressive with an average life expectancy of eight months to two years. The standard treatment is surgery to remove the tumor as completely as possible, followed by radiotherapy, usually in combination with chemotherapy. However, results are unsatisfactory, because these tumors are very resilient and soon start growing back. Therefore, there is an urgent need for new treatment approaches.

Tumors grow more aggressively and immune system is weakened

The Helmholtz Junior Research Group "Experimental Neuroimmunology" led by Professor Dr. Michael Platten of DKFZ and the Department of Neurooncology of Heidelberg University Hospital and the National Center for Tumor Diseases (NCT) headed by Professor Dr. Wolfgang Wick have come across the kynurenin molecule in their studies of human cancer cells and in the mouse model. Kynurenin is formed when the amino acid tryptophan -- a protein component taken in with food -- is broken down in the body. "We have been able to detect increased levels of kynurenin in cancer cells of glioma patients with particularly aggressive tumors," Professor Michael Platten explained. The current research results from Heidelberg show that this link also appears to exist in other types of cancer such as cancers of the bladder, bowel or lungs.

It was even more astonishing for the investigators to find that kynurenin activates a protein known as dioxin receptor. This, in turn, triggers a cascade of chemical reactions which ultimately promote tumor growth and weaken the immune system. So far, it had only been known that the dioxin receptor, scientifically called aryl hydrocarbon receptor (AHR), is activated by environmental toxins. "Why this receptor is even present in body cells and which is its activation partner in the body, was yet unknown," says Dr. Christiane Opitz, first author of the research article. "Kynurenin seems to have very similar effects as dioxin, but it is formed by the body itself," said Professor Platten.

Yet another new discovery was presented by the group: The amino acid tryptophan was broken down in cancer cells by a specific enzyme called tryptophan dioxygenase, or TDO for short, which scientists had previously found primarily in liver cells. "It came as a surprise to us that TDO is also active in cancer cells and strongly so in particularly aggressive tumors."

Searching for substances to specifically inhibit this metabolic pathway

The newly discovered metabolic pathway is a potential target for cancer treatment. The intention is to inhibit tumor growth and strengthen the immune system. "We will start searching for substances that specifically inhibit this metabolic pathway and may be used as potential antitumor drugs," said Professor Wolfgang Wick envisioning the next steps ahead.


Story Source:

The above story is based on materials provided by University Hospital Heidelberg. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christiane A. Opitz, Ulrike M. Litzenburger, Felix Sahm, Martina Ott, Isabel Tritschler, Saskia Trump, Theresa Schumacher, Leonie Jestaedt, Dieter Schrenk, Michael Weller, Manfred Jugold, Gilles J. Guillemin, Christine L. Miller, Christian Lutz, Bernhard Radlwimmer, Irina Lehmann, Andreas von Deimling, Wolfgang Wick, Michael Platten. An endogenous tumour-promoting ligand of the human aryl hydrocarbon receptor. Nature, 2011; DOI: 10.1038/nature10491

Cite This Page:

University Hospital Heidelberg. "Dioxin-like chemical messenger makes brain tumors more aggressive." ScienceDaily. ScienceDaily, 7 October 2011. <www.sciencedaily.com/releases/2011/10/111006102615.htm>.
University Hospital Heidelberg. (2011, October 7). Dioxin-like chemical messenger makes brain tumors more aggressive. ScienceDaily. Retrieved November 25, 2014 from www.sciencedaily.com/releases/2011/10/111006102615.htm
University Hospital Heidelberg. "Dioxin-like chemical messenger makes brain tumors more aggressive." ScienceDaily. www.sciencedaily.com/releases/2011/10/111006102615.htm (accessed November 25, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Tuesday, November 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Are Female Bosses More Likely To Be Depressed?

Are Female Bosses More Likely To Be Depressed?

Newsy (Nov. 24, 2014) A new study links greater authority with increased depressive symptoms among women in the workplace. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins