Ependymomas are glial tumors that share morphologic similarities with ependymal cells. Here we laser microdissected ependymoma cells of 15 infratentorial tumors and generated gene expression profiles. These profiles were compared to those of 7 laser microdissected ependymal tissues. Overall design: 10 000 laser microdissected cells of each of the 15 different infratentorial ependymomas and seven ependymal autopsy tissues were lysed and gene expression profiles were generated. Expression profiles of ependymomas were compared to those of ependymal cells.