A detailed genetic analysis of medulloblastoma, the most common type of childhood cancerous brain tumour, reveals new insights that may aid the development of novel treatments. The findings are reported in this week’s Nature.
Current therapies for medulloblastoma have unpleasant side effects that can impair the child’s quality of life. In addition, the disease is divided into several subtypes, which have distinct clinical features and different clinical responses to treatments. Thus, there is a need to develop new targeted therapies with reduced toxic effects.
Paul Northcott and colleagues assessed the genetic underpinnings of medulloblastoma by analysing genome sequences of 491 medulloblastomas and examining altered gene expression in a further 1,256 samples. They identify new genetic alterations that drive the development of this cancer, many of these specific to subgroups, especially in previously less-well-understood subgroups (Group 3 and Group 4, which together contribute to more than 60% of all medulloblastomas). In addition, some of the novel genetic drivers and alterations to cellular pathways uncovered by the authors could be grouped into new tumour subtypes, further demonstrating that medulloblastoma should be considered as a collection of diseases rather than a single entity.
The newly identified cancer genes and unique features of specific subtypes may provide attractive targets for treating medulloblastoma, the authors conclude.