CNS germinomas show global demethylation, chromosomal instability and mutational activation of the Kit-, Ras/Raf/Erk- and Akt-pathways

Introduction: Only limited information is available on their genomic, epigenetic and biological alterations of CNS germinomas. Methods: A genome-wide analysis of chromosomal copy number alterations was performed in 49 CNS germinomas by molecular inversion profiling. CpG methylation was studied by immunohistochemistry of methylated cytosine residues. KIT and RAS family members were sequenced. Ras/Erk and Akt pathway activation was analyzed by immunostaining of p-Erk, p-Akt, p-mTOR and p-S6. Results: Germinomas showed global DNA demethylation and genomic instability with high frequency of regional gains and losses…