Potential biomarker discovered to allow more precise classification of malignant brain tumours in children

July 24, 2017
Potential biomarker discovered to allow more precise classification of malignant brain tumours in children. Credit: Medical University of Vienna

After leukaemia, primary tumours of the brain and spinal cord are the second commonest cancers in childhood and adolescence. The presence of the enzyme telomerase characterises a particularly malignant subgroup of cerebellar ependymomas and, in addition to the known markers, could provide information that allows a more accurate prognosis and hence also choice of treatment. This was shown by a study conducted at MedUni Vienna and Vienna General Hospital within the framework of the Comprehensive Cancer Center (CCC) and in collaboration with the German Cancer Research Center in Heidelberg. The study has now been published in leading journal Nero-Oncology.

Ependymomas are the third commonest central nervous system tumours in children. They are often highly aggressive within this age-group and the prognosis for patients is poor. In Austria, nine children a year are diagnosed with this type of tumour. The current treatment is surgical removal followed by radiotherapy and chemotherapy.

Many subtypes – one name

The most recent research has shown that ependymomas are not an homogenous type of tumour but can be divided into several subgroups, based on their molecular biological characteristics. These subgroups all have different prognoses and therefore probably also require different treatment.

Enzyme stimulates tumour growth

The new study by Johannes Gojo, junior doctor and researcher at the Department of Pediatrics and Adolescent Medicine of MedUni Vienna and Vienna General Hospital and member of the CCC, investigated whether the could be used as a biomarker for ependymomas. Says Gojo: "We were able to show that was primarily reactivated in tumours that exhibit a particularly aggressive course. This means that, despite and subsequent radiotherapy and chemotherapy, the tumour recurred." The scientists suspect that this will enable them to identify patients who would benefit from more intensive treatment. Conversely, patients with less aggressive tumours could be spared chemotherapy. This would mean a huge improvement in quality-of-life for those affected. Says Gojo: "Thus, together with other parameters, the presence of telomerase could be a big help in deciding on the course of treatment. It therefore represents a highly promising biomarker. However, before we can use the concept clinically, it needs to be validated in further studies."

The study team were also able to gain initial insights into the mechanisms that lead to reactivation of telomerase.

Telomeres determine lifetime

"Human are mortal. This means that their lifetime is not determined by the clock or the calendar but by their ability to divide: the longer the so-called telomeres, the more often the cells are able to divide," explains Walter Berger, Deputy Head of the Institute of Cancer Research at MedUni Vienna, member of the CCC and joint corresponding author of the study, alongside Christine Haberler of the Institute of Neurology.

Telomeres are "caps" on the end of chromosomes, which protect the chromosomes from breaking and hence "fraying", as it were, which would result in cell damage. The telomeres shorten with each cell division. If the telomeres are too short or if the cell loses the ability to produce telomerase, it initiates cell death and dies. The enzyme telomerase can preserve telomeres or at least can restore them to their original length. Many tumours have the ability to reactivate telomerase, which then facilitates unrestricted growth.

The results of the study have now been published in Neuro-Oncology, one of the leading specialist journals in this field. Appearing in the same issue was an expert commentary from two international experts, who rated the paper as highly relevant.

Explore further: Regulation of telomerase in stem cells and cancer cells

More information: Johannes Gojo et al. Telomerase activation in posterior fossa group A ependymomas is associated with dismal prognosis and chromosome 1q gain, Neuro-Oncology (2017). DOI: 10.1093/neuonc/nox027

Michal Zapotocky et al. Can telomerase activity be unleashed to refine prognosis within ependymoma subgroups?, Neuro-Oncology (2017). DOI: 10.1093/neuonc/nox059

Related Stories

Regulation of telomerase in stem cells and cancer cells

June 27, 2012
Scientists at the Max Planck Institute of Immunobiology and Epigenetics in Freiburg have gained important insights for stem cell research which are also applicable to human tumours and could lead to the development of new ...

Study explores possible 'safe and effective' anti-cancer therapy

February 3, 2012
(Medical Xpress) -- New findings discovered by an international research team, which includes a professor from Western University, may lead to a safe and effective anti-cancer therapy.    A report published online ...

Research reveals how cancer-driving enzyme works

May 6, 2011
Cancer researchers at UT Southwestern Medical Center are helping unlock the cellular-level function of the telomerase enzyme, which is linked to the disease's growth.

'In vivo' reprogramming induces signs of telomere rejuvenation

February 2, 2017
During the 'in vivo' reprogramming process, cellular telomeres are extended due to an increase in endogenous telomerase. This is the main conclusion of a paper published in Stem Cell Reports by a team from the Spanish National ...

Recommended for you

Many pelvic tumors in women may have common origin—fallopian tubes

October 17, 2017
Most—and possibly all—ovarian cancers start, not in ovaries, but instead in the fallopian tubes attached to them.

New bowel cancer drug target discovered

October 17, 2017
Researchers at the Francis Crick Institute have discovered a new drug target for bowel cancer that is specific to tumour cells and therefore less toxic than conventional therapies.

Researchers find novel mechanism of resistance to anti-cancer drugs

October 17, 2017
The targeted anti-cancer therapies cetuximab and panitumumab are mainstays of treatment for advanced colorectal cancer, the second leading cause of cancer-related deaths in the United States. However, many patients have tumors ...

Using artificial intelligence to improve early breast cancer detection

October 17, 2017
Every year 40,000 women die from breast cancer in the U.S. alone. When cancers are found early, they can often be cured. Mammograms are the best test available, but they're still imperfect and often result in false positive ...

New assay may boost targeted treatment of non-Hodgkin lymphoma

October 17, 2017
Diffuse large B-cell lymphoma (DLBCL) is an aggressive cancer and the most frequently diagnosed non-Hodgkin lymphoma worldwide (nearly 40% of cases). Recent advancements indicate that both the prognosis and choice of treatment ...

Biology of childhood brain tumor subtypes offers clues to precision treatments

October 17, 2017
Researchers investigating pediatric low-grade gliomas (PLGG), the most common type of brain tumor in children, have discovered key biological differences in how mutated genes combine with other genes to drive this childhood ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.