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 Minimising risks of transplants
22.02.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

nachricht FAU researchers demonstrate that an oxygen sensor in the body reduces inflammation
22.02.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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: 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...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

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

Stiffness matters

22.02.2018 | Life Sciences

Magnetic field traces gas and dust swirling around supermassive black hole

22.02.2018 | Physics and Astronomy

First evidence of surprising ocean warming around Galápagos corals

22.02.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>