Overactive Signaling Pathway Responsible for Brain Tumors in Children
A group of scientists, led by Professor Dr. Stefan Pfister of the German Cancer Research Center, have found a common thread amongst brain tumors in children.
The research team is part of the International Cancer Genome Consortium, a network of scientists from 15 countries, that aims to develop a comprehensive description of genomic and epigenomic changes in all significant types of cancer.
96 Cases Analyzed
For the purpose of the study researchers examined 96 cases in all. The genome analyses revealed an overactive signaling pathway in all the cases of pilocytic astrocytoma, the most common form of brain cancer in children.
Pilocytic astrocytomas tumors typically grow slowly. However, they are difficult to access by surgery and therefore cannot be totally eradicated. 50 percent of the pilocytic astrocytomas develop in the cerebellum, while the rest develop in various other regions of the brain.
Brain cancer is the main cause of mortality in children. Even in cases where the condition is cured, it can have a debilitating impact on the child’s life. Among other things, the patient suffers from the stress of a treatment. In some cases, the tumor can lead to retardation of the brain development.
MAPK Signaling Pathway
Stefan Pfister had been involved in similar studies with another researcher David Jones. “A couple of years ago, we had already hypothesized that pilocytic astrocytomas generally arise from a defective activation of MAPK signaling.”
At that time, gene mutations were not identified in twenty percent of the cases. In the present study, researchers have been able to uncover the “activating defects in three other genes involved in the MAPK signaling pathway.” These defects were not previously described in astrocytoma.
“Aside from MAPK mutations, we do not find any other frequent mutations that could promote cancer growth in the tumors. This is a very clear indication that overactive MAPK signals are necessary for a pilocytic astrocytoma to develop,” confirmed Stefan Pfister.
The findings of the study have been published in the latest issue of the journal Nature Genetics.