Abstract 3455: Comparison of expression profiles of pediatric high and low grade brainstem gliomas to pediatric supratentorial high grade astrocytomas

Abstract

Abstract Diffuse intrinsic pontine gliomas (DIPG) are one of the most devastating pediatric malignancies and currently the number one cause of brain tumor related death in children with a 10-12 month median survival. Despite this very little is understood about the biology of these tumors. We have already shown potential novel therapeutic targets for DIPG using high-resolution SNP-based analysis. We performed high resolution genetic analysis using whole-genome single-nucleotide polymorphism (SNP) arrays (Affymetrix 500K and 6.0) on post mortem tumor with matched normal brain samples (n=9) and surgical samples (n=2) for a series of DIPG patients as well as pediatric supratentorial high grade astrocytomas (sHGA, n=20). Here we extend our initial study to include expression array analysis, amalgamating the datasets to generate a more complete understanding of the genetic alterations underlying brainstem gliomas. Expression profiling using Illumina HumanHT-12 arrays was conducted on 26 high grade brainstem gliomas, including 23 DIPGs, 51 low grade brainstem gliomas and 30 supratentorial high grade astrocytomas. Expression profiles highlighted the distinctiveness of DIPGs when compared to high grade supratentorial astrocytomas. Analysis resulted in two groups of DIPGs when clustering based on most significant differentially expressed genes (p < 0.005) with one group being more similar to pediatric low grade brainstem gliomas and the other distinct from both the supratentorial high grade tumors and other brainstem gliomas. This data will increase our understanding of brainstem glioma biology, information crucial to the development of agents targeted more specifically towards this devastating disease. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3455. doi:10.1158/1538-7445.AM2011-3455