Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Variant in gene associated with telomeres predicts longer survival of deadly brain tumor

19.04.2005


An exceptionally large study of patients with glioblastoma multiforme has found an association between a genetic variation and a doubling of survival rate - the strongest link ever established between genetic variation and outcome in this deadliest form of brain cancer, according to researchers at The University of Texas M. D. Anderson Cancer Center.



The study, presented at the annual meeting of the American Association of Cancer Research, found the differences in a common variant in a number of repeats (short or long) of the hTERT gene, which produces human telomerase.

This study of 301 patients, which the researchers believe is the largest to date of patients with glioblastoma multiforme, found that the 36 patients (about 11 percent) who had the "SS" variant genotype of hTERT survived an average of 25 months, compared to about 14 months for those who had either the "SL" or "LL" genotypes.


The findings are exciting, says the lead investigator, Melissa Bondy, Ph.D., a professor in the Department of Epidemiology, because they suggest new treatment directions for patients with a cancer that is both the most common glioma and the one offering the poorest hope of survival.

"It is a real advance because we have never seen any genotype that can stratify glioblastoma multiforme patients into different treatment outcome groups like this," says Bondy. "Now we need to verify the finding, study the mechanism, and see if there is a way that these results can be used either as a biomarker or to individualize treatment."

For example, if the SS variant genotype of hTERT is confirmed to have better response to chemotherapy and radiation treatment, then it is possible that these therapies will extend survival for patients with glioblastoma multiforme, she says.

Telomeres, the structures that cap the end of cellular chromosomes, have been linked to both the aging process and cancer development. Telomerase is an enzyme that helps regulate the length of telomeres, and in normal cells, it is not generally active past fetal development. Thus, telomeres shorten each time a cell divides, until they cannot protect chromosomes and the cell dies. But in cancer, it is believed that telomerase is activated and intervenes to keep telomeres from shortening, allowing for unlimited cell division.

The research group looked at genetic variation of hTERT because abnormal expression of the gene contributes to unregulated cell growth, and expression of the gene has been evaluated as one of the most common tumor markers in most primary tumors, says the study’s first author, Luo Wang, M.D., Ph.D., a research scientist in the Department of Epidemiology.

The mechanism why the SS variant genotype of hTERT showed better survival remains unknown. But some forms of hTERT may be less destructive than others because they may be expressed at a lower level, Wang says. For instance, the SS variant genotype is more likely than the SL or LL variant genotype to produce an antisense-like molecule that suppresses the expression of human telomerase, he says, and this modulation may enhance the effect of the chemotherapy and radiation treatment on the patients with the SS variant genotype.

Bondy says the association between the SS variant genotype and improved outcome held, even when differences in age, sex and the extent of surgery, chemotherapy and radiation were taken into account. "We have looked at a lot of different genes associated with cancer, such as DNA repair genes and p53, but this is the first time we have found a genotype that has such a large effect on clinical outcome."

Nancy Jensen | EurekAlert!
Further information:
http://www.mdanderson.org

More articles from Life Sciences:

nachricht New gene catalog of ocean microbiome reveals surprises
18.08.2017 | University of Hawaii at Manoa

nachricht Organ Crosstalk: Fatty Liver Can Cause Damage to Other Organs
18.08.2017 | Deutsches Zentrum für Diabetesforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New gene catalog of ocean microbiome reveals surprises

18.08.2017 | Life Sciences

Astrophysicists explain the mysterious behavior of cosmic rays

18.08.2017 | Physics and Astronomy

AI implications: Engineer's model lays groundwork for machine-learning device

18.08.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>