Expression of the oligodendroglial lineage-associated markers Olig1 and Olig2 in different types of human gliomas.
Because a specific group of oligodendrogliomas is susceptible to adjuvant therapy, it is important to elucidate the biological characteristics of these tumors. In situ hybridization analyses have revealed that Olig genes are expressed in oligodendroglial lineage cells and are highly expressed in oligodendrogliomas. To clarify whether OLIG is a tumor-specific marker for oligodendrogliomas, we have investigated the expression of Olig transcripts by semiquantitative RT-PCR assay and OLIG2 protein with a new antibody in a variety of glial tumors. The semiquantitative RT-PCR revealed that high levels of expression of Olig1 and Olig2 mRNAs were present in anaplastic oligodendrogliomas and anaplastic astrocytomas, while expression of these mRNAs in grade IV glioblastomas was lower than in grade II and grade III gliomas (p < 0.01). Immunohistochemical analyses demonstrated that the mean immunopositive proportion of OLIG2 was 82% in anaplastic oligodendrogliomas but only 34% in anaplastic astrocytomas. Therefore, although OLIG2 expression was detected in a range of gliomas not specific for oligodendrogliomas, the expression level in anaplastic oligodendrogliomas was more uniform and intense than that in other glial tumors. In conclusion, combining Olig mRNA expression and immunohistochemistry of OLIG2 enables oligodendrogliomas to be distinguished from glioblastomas and other astrocytic glial tumors.
Laboratory of Molecular and Cellular Pathology, Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Akiko
A
Ohnishi
Hirofumi
H
Sawa
Masumi
M
Tsuda
Yutaka
Y
Sawamura
Tomoo
T
Itoh
Yoshinobu
Y
Iwasaki
Kazuo
K
Nagashima
D000293:Adolescent; D000310:Adrenal Gland Neoplasms; D000328:Adult; D000368:Aged; D000375:Aging; D051792:Basic Helix-Loop-Helix Proteins; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D004268:DNA-Binding Proteins; D045888:Ganglion Cysts / Q000378:metabolism; D005909:Glioblastoma / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D007223:Infant; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D000076104:Oligodendrocyte Transcription Factor 2; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D009419:Nerve Tissue Proteins; D000076104:Oligodendrocyte Transcription Factor 2; D012333:RNA, Messenger; C405707:OLIG1 protein, human; C405708:OLIG2 protein, human