Abstract 2492: Integrated genomics on molecular subgroups in medulloblastoma

• Published in: Cancer research (Chicago, Ill.) Ill.), 2012-04, Vol.72 (8_Supplement), p.2492-2492
• Main Authors: Kool, Marcel, Jones, David T.W., Remke, Marc, Jaeger, Nathalie, Korshunov, Andrey, Schlanstein, Maria, Northcott, Paul A., van Meeteren, Netteke Schouten, van Vuurden, Dannis, Clifford, Steven C, Pietsch, Torsten, Von Bueren, Andre O., Rutkowski, Stefan, Cho, Yoon-Jae, McCabe, Martin, Collins, Peter, Haberler, Christine, Ellison, David, Gilbertson, Richard, Pomeroy, Scott, Doz, Francois, Delattre, Olivier, Taylor, Michael D., Lichter, Peter, Pfister, Stefan M.
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM2012-2492

Medulloblastoma is the most common malignant brain tumor in childhood. Molecular studies from several groups around the world demonstrated that medulloblastoma is not one disease but comprises a collection of distinct molecular subgroups. However, all these studies reported on different numbers of subgroups. The current consensus is that there are only four major subgroups, which are now called WNT, SHH, Group 3 and Group 4. A better understanding of each of these molecular subtypes is urgently warranted to improve treatment strategies and the overall survival of patients and ultimately also the quality of life for those that survive medulloblastoma. We used the data of seven independent studies on medulloblastoma for further characterization of these molecular subtypes. All cases (n = 550) were analyzed by expression profiling and for most cases SNP or array-CGH data were available. Data are presented for all medulloblastomas together and for each subgroup separately. For validation purposes we compared the results of this meta-analysis with another large medulloblastoma cohort (n = 408) for which subgroup information was obtained by immunohistochemistry. Results from both cohorts are highly similar and show how distinct the molecular subtypes are with respect to their transcriptome, DNA copy number aberrations, demographics, and survival. Interestingly, the data also showed how different medulloblastomas are between infants, children and adults. In infants, for instance, almost all medulloblastomas are classified as SHH or Group 3, whereas in adults most medulloblastomas are of the SHH subtype and almost never of Group 3. Recent next generation sequencing data (whole genome and exome) generated in our laboratory for a large series of pediatric and adult medulloblastomas show that the spectrum of genetic mutations is also very different, not only between the molecular subtypes, but also between the different age categories. All these data clearly show that medulloblastoma is not one disease. Results from these molecular analyses will form the basis for prospective multi-center studies and will have an impact on how the different variants of medulloblastoma will be treated in the future. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2492. doi:1538-7445.AM2012