Cdc6 expression as a marker of proliferative activity in brain tumors

Antibodies against human proteins that regulate DNA replication such as Cdc 6 and Mcm5 became available as a new marker of proliferation. We performed immunohistochemical analysis with MIB-1 and antibody against Cdc6 on 35 bra in tumors, including tumors of neuroepithelial tissue, vestibular schwannom as, meningiomas, and pituitary adenomas. Median reactivity for MIB-1 was 8. 8%, and that for Cdc6 was 55%. Reactivity in most brain tumors was signific antly higher for Cdc6 than for MIB-1, but reactivity of Cdc6 was independen t Of tumor grade. Detection of Cdc6 expression might be useful for the esti mation of proliferative activity in brain tumors.