Expression data from ependymoma surgical samples

Ependymoma, the 3rd most common brain tumor in children, recurs in approximately 50% of patients. There is currently no robust marker that predicts for recurrence, which is a significant clinical problem We used global gene expression profiling of 19 patient surgical samples obtained at initial diagnosis and with known clinical outcomes to discover novel prognostic markers. Gene expression profiles were generated from surgical tumor samples using Affymetrix HG-U133plus2 chips. Profiles were divided into recurrent and non-recurrent groups in order to identify differentially expressed genes that were associated with risk of recurrence. In addition, time to progression was correlated with gene expression as a continuous variable in the recurrent group.