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An in-depth analysis of medulloblastoma brain tumours has identified faulty genes underlying the disease.
The researchers hope that their findings could be used to develop new, targeted treatments that are more personal for patients with this type of brain tumour.
“Our goal is to understand each patient’s tumour at the molecular level in order to better tailor treatment,” said co-first author Dr Paul Northcott. The work is led by St. Jude Children’s Research Hospital in the US and the German Cancer Research Centre and published in the journal Nature.
Professor Steven Clifford, a Cancer Research UK-funded expert in medulloblastoma at Newcastle University, said that this is the largest such study in the disease and will be an important resource.
Medulloblastoma is the most common brain tumour in children. The disease is split into four groups, each differing in terms of patient survival and the type of brain cells that the disease starts in.
While progress has been made in understanding some of the genetic flaws underlying these distinct types, there isn’t yet a comprehensive picture of what goes wrong in this complex disease.
The researchers combed through the DNA of almost 500 people with medulloblastoma, comparing samples from normal and tumour tissue. They also sifted through data from a further 1,256 patients to look how active different genes were.
According to lead researcher Dr Peter Lichter, disease-causing genes were previously only understood in about 30% of tumours belonging to groups 3 and 4. The new data has significantly expanded that figure, the researchers claim, identifying such genes in the majority of cases looked at in this study.
The researchers found genetic changes or faulty molecular pathways in more than 75% of the tumour samples included in the study. Two of the faulty genes hadn’t been linked with cancer before, and were found only in the least understood disease groups – 3 and 4.
Alongside helping to refine the classification of this complex disease, the researchers believe that this work could boost research into more precise treatments by finding potential new targets for therapy.
The results also come shortly after two other similar studies that were published within the last few of months. Clifford said that to find new effective treatments the findings need to be considered altogether.
“The key next steps will be to understand the role and function of the genes described in the study, and whether they could be targeted with treatments – which the study doesn’t address,” he added.
Northcott, P. A. et al. (2017). The whole-genome landscape of medulloblastoma subtypes. Nature. doi:10.1038/nature22973