TCP1 and ependymal tumor: Some genes mapping to the long arm of chromosome 6 have previously been reported to be downregulated in ependymal tumors, including SASH1 [a candidate tumor suppressor gene in breast (40) and colon (41) cancer], TCP1 (involved in tubulin function), ADM1 and CDK11 (involved in cell proliferation) (15,42,43).