title: Primary brain tumors differ in their expression of octamer deoxyribonucleic acid-binding transcription factors from long-term cultured glioma cell lines.
abstract: Nervous system-specific transcription factors that bind to the octameric deoxyribonucleic acid sequence motif ATGCAAAT (or ATTTGCAT) are known as N-Oct proteins. Neurons and glia contain the ubiquitous Oct-1 protein and four polypeptide complexes termed N-Oct-2, N-Oct-3, N-Oct-4, and N-Oct-5. Previously, we showed that N-Oct proteins are differentially expressed by human neuroblastoma and glioblastoma cell lines in vitro. We have now extended this work to freshly isolated human primary and metastatic brain tumors. Contrary to brain tumor cell lines, of the five astrocytomas and three glioblastomas analyzed, all but two tumors displayed the complete N-Oct protein profile, irrespective of histopathological tumor grade. Two astrocytomas were negative for N-Oct-4. Ten of 13 ependymomas exhibited N-Oct-2, N-Oct-3, and N-Oct-4 but lacked the N-Oct-5 complex. In contrast, brain metastases of two patients with extracerebral carcinomas contained only Oct-1, and cerebral metastases from two cases of B cell lymphomas showed Oct-1 and Oct-2 complexes, the characteristic Oct protein pattern of B lymphocytes. Thus, metastatic carcinoma and lymphoma expressed a non-nervous system phenotype of Oct proteins.
authors.affiliation: University Hospital Zurich, Department of Internal Medicine, Switzerland.
authors.forename: E
authors.initials: E
authors.lastname: Schreiber
authors.forename: R E
authors.initials: RE
authors.lastname: Merchant
authors.forename: O D
authors.initials: OD
authors.lastname: Wiestler
authors.forename: A
authors.initials: A
authors.lastname: Fontana
mesh_terms: D001254:Astrocytoma / Q000235:genetics / Q000473:pathology; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology / Q000556:secondary / Q000601:surgery; D004273:DNA, Neoplasm / Q000235:genetics*; D004268:DNA-Binding Proteins; D004806:Ependymoma / Q000235:genetics / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D005909:Glioblastoma / Q000235:genetics / Q000473:pathology; D018398:Homeodomain Proteins; D006801:Humans; D009367:Neoplasm Staging; D050813:Octamer Transcription Factor-2; D050814:Octamer Transcription Factor-3; D009837:Oligodendroglioma / Q000235:genetics / Q000473:pathology; D050809:POU Domain Factors; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D050813:Octamer Transcription Factor-2; D050814:Octamer Transcription Factor-3; D050809:POU Domain Factors; C058435:POU2F2 protein, human; C494173:POU5F1 protein, human; D014157:Transcription Factors; C085076:transcription factor Brn-2