Genetics of Children’s Brain Tumour Unlocked
17 May 2010 - ICR scientists have identified an important cancer gene that could lead to more effective drugs being developed to fight paediatric high grade glioma.
The team compared detailed scans of tumour genomes from 78 newly-diagnosed paediatric patients to samples of adult gliomas, looking through 500,000 individual pieces of DNA for variations in the number of copies of each. In paediatric gliomas, a gene called PDGFRA on chromosome 4q12 was commonly amplified and there were often extra copies of chromosome 1q. These changes are rarely seen in the adult form of the disease. Clinical differences had already been observed between the adult and paediatric forms, but this study is the first to show underling genetic differences.
“We found significant differences between the genomes of adult and young people’s gliomas. This is an important finding because it means studies on adult gliomas cannot simply be applied to younger patients, and it has particular implications for drug trials,” Lead author Dr Chris Jones said.
The researchers also tracked gene activity in 53 of the tumour samples, and compared the results with adult gliomas. Paediatric glioma tumours that did not have the PDGFRA alteration were nevertheless found to have associated genes switched on, suggesting that this biological pathway is a key to the development of this childhood cancer. The PDGFRA gene carries instructions for making a protein found on the cell surface, which is part of a pathway that helps control cell growth, proliferation and survival – processes that are commonly disrupted in cancer.
