Ependymomas are the second most frequent type of malignant brain tumor in children. Ependymoma develops from precursor cells of the tissue that lines the hollow cavities of the brain. Therapy results of ependymoma vary immensely: While in some patients tumor growth comes to a standstill after surgery and radiotherapy, in other children the disease rapidly takes a severe course. In about half of those affected the tumor continues to grow and the patients often succumb to the disease.
It is the patients with a severe course, in particular, who urgently need better therapies. To this end, we need to understand what makes ependymomas so different in their characteristics," says pediatrician and molecular geneticist Dr. Stefan Pfister, who is a researcher at DKFZ and Heidelberg University Hospitals. Jointly with his colleague, Dr. Hendrik Witt, Pfister and researchers from Canada, the U.S.A., Russia, Poland and Italy are now publishing the results of the largest ever molecular-genetic study of ependymomas of the cerebellum. This is where this type of tumor is most frequently located in children, while in adults ependymoma usually arises in the cerebrum or in the spinal cord.
In 583 tissue samples of ependymomas of the cerebellum, the investigators studied the activity of individual genes and searched the genetic material for losses or gains of whole DNA segments. Two groups of these tumors were first analyzed independently and the results obtained were subsequently validated based on the tissue samples of a third group. In this way, the investigators obtained particularly valuable results.
The large-scale study has yielded clear results: Based on anomalies of their genetic material, ependymomas of the cerebellum can be classified in two distinct subgroups which also differ clinically. Group A ependymomas take an unfavorable course; such tumors often recur after initial surgery and they frequently metastasize, which ultimately leads to
|Contact: Dr. Sibylle Kohlstdt|
Helmholtz Association of German Research Centres