Expression of cyclin A and topoisomerase IIalpha of oligodendrogliomas is correlated with tumour grade, MIB-1 labelling index and survival.
OBJECTIVE
This study was designed to investigate immunoexpression of cyclin A and D1, and topoisomerase IIalpha in oligodendrogliomas and to evaluate the correlation with MIB-1 (Ki67), tumour grade, and survival of the patients.


RESULTS
Forty cases of oligodendrogliomas (20 high- and 20 low-grade) were studied immunohistochemically with the above-mentioned monoclonal antibodies.


RESULTS
Normal brain tissues included in tumour sections did not express any of cyclin A, MIB-1 and topoisomerase IIalpha except cyclin D1, which was shown in perineuronal and interfascicular normal oligodendroglial cells. In low-grade and high-grade oligodendrogliomas, the mean cyclin A labelling index (LI) was 1.18 +/- 0.98% versus 4.65 +/- 1.99%, respectively; the mean topoisomerase IIalpha LI was 1.32 +/- 1.04% versus 6.63 +/- 4.31%, respectively; and the mean MIB-1 LI was 1.69 +/- 1.55% versus 9.46 +/- 4.66%, respectively. Interestingly, cyclin D1 was not expressed in any oligodendrogliomas. Both cyclin A and topoisomerase IIalpha LI showed a significant positive correlation with MIB-1 LI and histological grade of oligodendrogliomas (P < 0.01) and an inverse correlation with overall survival (P < 0.01). Univariate analysis showed that cyclin A and topoisomerase IIalpha LIs with a cut-off point at 3% were a significant prognostic factor (P: cyclin A = 0.0040, topoisomerase IIalpha = 0.0033).


CONCLUSIONS
Cyclin A and topoisomerase IIalpha expression are closely correlated with anaplastic oligodendrogliomas and worse clinical outcomes. Cyclin D1 seems not to be involved in the tumorigenesis of oligodendrogliomas.
Park
S-H
SH
Department of Pathology, Ilsanpaik Hospital, Inje University College of Medicine, Seoul, Korea.
Suh
Y-L
YL
D000328:Adult; D000951:Antigens, Neoplasm; D001932:Brain Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D019925:Cyclin A / Q000378:metabolism*; D019938:Cyclin D1 / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D015996:Survival Rate
D000951:Antigens, Neoplasm; D019925:Cyclin A; D004268:DNA-Binding Proteins; D019394:Ki-67 Antigen; D019938:Cyclin D1; D004250:DNA Topoisomerases, Type II