Transcription profiling of human ependymoma tumors with known clinical outcomes

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. Experiment Overall Design: 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.