HIGH-GRADE HUMAN BRAIN-TUMORS EXHIBIT INCREASED EXPRESSION OF MYELIN TRANSCRIPTION FACTOR-1 (MYT1), A ZINC-FINGER DNA-BINDING PROTEIN

Detection and characterization of distinct central nervous system (CNS ) tumor cell types is clinically important since distinct tumor types are associated with different prognoses and treatments. However, there is currently a lack of markers to identify certain glioma types and i nsufficient understanding as to which cells give rise to different gli oma cell types. In the present study, biopsy specimens from human brai n tumors were analyzed for expression of Myelin Transcription Factor 1 (MYT1) to explore the extent to which glioma cells reflect characteri stic expression of MYT1 in developing glial progenitor cells. Immunost aining with an antibody against MYT1 revealed widespread immunoreactiv ity that was most prominent in high-grade oligodendrogliomas, astrocyt omas, and mixed oligoastrocytomas as well as in a dysembryoplastic neu roepithelial tumor. MYT1 immunoreactivity in turner regions generally correlated with the prevalence of cells exhibiting nuclear immunolabel ing with an antibody against Ki-67, suggesting an association of MYT1 with cell proliferation that was also observed in normal adult human a nd rat brain in the germinal subependymal zone. The MYT1 immunoreactiv ity was frequently nuclear, appearing as dotted or punctate, but in so me cases it was localized to the cytoplasm. In combination with histop athological studies and analysis of Ki-67 immunoreactivity, examinatio n of MYT1 immunolabeling may provide additional information to aid in the detection and diagnosis of CNS tumors.