Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brain tumor growth requires abnormal neighbors

15.12.2003


For some brain tumors, the key to success is not just what you know but who you know, according to researchers at Washington University School of Medicine in St. Louis.



In trying to develop a mouse model of neurofibromatosis 1 (NF1), a genetic disorder that predisposes children to certain types of brain tumors, the team discovered that tumors only developed when all brain cells were genetically abnormal, not just the cell type that becomes cancerous. The study is featured on the cover of the Dec. 15 issue of the journal Cancer Research.

"We are quite excited about this report as it represents the first model of this type of tumor," says principal investigator David H. Gutmann, M.D., Ph.D., the Donald O. Schnuck Family Professor of Neurology. "We’ve always assumed that cancer results from the loss of specific genes in a particular cell, but apparently that isn’t always the case. Our findings suggest that as in real estate, location is everything – a permissive environment may be the key to whether a tumor cell becomes cancerous or just sits dormant for a person’s entire life."


According to the National NF Foundation, NF1 is the most common neurological disorder caused by a single gene. The disorder can lead to a variety of complications including skin, spine and brain cancer. Up to 20 percent of patients with NF1 develop tumors in a type of support cell called an astrocyte along the optic nerve and optic chiasm, which transmit visual information from the eye to the brain.

Astrocytes that develop into tumors lack both copies of the Nf1 gene. So Gutmann’s team first developed genetically engineered mice in which all cells were normal except astrocytes, which lacked both copies of the Nf1 gene. To their surprise, the mice did not develop brain tumors.

Humans with NF1 are born with one normal and one mutated copy of the Nf1 gene in all cells in their bodies. Gutmann’s team therefore hypothesized that genetic abnormalities in brain cells surrounding astrocytes might be essential for tumor formation.

To test this theory, the team developed mice with no functional copies of the Nf1 gene in their astrocytes and only one functional copy in all other brain cells, a scenario identical to that of humans with the disease. Every mouse developed astrocyte tumors along the optic nerve or chiasm within the first 10 months.

According to Gutmann, understanding the events that lead to tumor growth is critical for learning how to predict -- and hopefully prevent -- tumors.

"It’s clear from our findings that tumors do not form simply by losing both copies of the Nf1 gene," he explains. "If we figure out what external cues are necessary to trigger tumor growth, we could try to shut off that switch and stop tumors dead in their tracks without having to correct the underlying genetic defect."

The potential for the mouse model used in this study to serve as a preclinical model of NF1 is enhanced by the team’s ability to detect tumors in their very early stages using a powerful 4.7-Tesla magnetic resonance imaging (MRI) scanner and algorithms developed by Gutmann’s colleagues at the Mallinckrodt Institute of Radiology at the School of Medicine. Their techniques and equipment enable them to detect tumors the size of a piece of thread.

"We’re now beginning to detect these tumors even earlier using MRI," Gutmann says. "I think we’ve gotten to the point where this mouse model can not only help us understand more about the cell biology underlying brain tumor development, but also provides a tool for developing and evaluating better treatments."


###
Bajenaru ML, Hernandez MR, Perry A, Zhu Y, Parada LF, Garbow JR, Gutmann DH. Optic nerve glioma in mice requires astrocyte Nf1 gene inactivation and Nf1 brain heterozygosity. Cancer Research, vol. 63, pp. 8573-77, Dec. 15, 2003.

Funding from the National Institutes of Health, the Small Animal Imaging Resource Program, the United States Army Medical Research and Material Command’s Office of Congressionally Directed Medical Research Programs and the National Neurofibromatosis Foundation supported this research.

The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Gila Z. Reckess | EurekAlert!
Further information:
http://medinfo.wustl.edu/

More articles from Health and Medicine:

nachricht NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)

nachricht High speed video recording precisely measures blood cell velocity
15.11.2017 | ITMO University

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>