Title

Expression of Telomerase RNA Component Correlates with the MIB-1 Proliferation Index in Ependymomas.

Publication/Presentation Date

Fall 10-1-1997

Abstract

Although there is general agreement that certain morphologic subtypes of ependymoma are benign, the biologic behavior of other ependymal neoplasms is poorly understood and not clearly related to conventional histopathologic criteria. The absence of universally accepted standards has prompted the search for more objective biologic markers. Telomerase is an RNA-containing enzyme associated with immortality in proliferating stem cells and many tumors. We investigated the proliferative activity of 26 ependymomas as determined by MIB-1 immunolabeling and compared the results with the in situ expression of human telomerase RNA (hTR) and WHO tumor grade. The study included 9 WHO grade I ependymomas (6 subependymomas and 3 myxopapillary ependymomas), 13 WHO grade II ependymomas, and 4 anaplastic (WHO grade III) ependymomas. The proliferation index (PI) and telomerase RNA expression were significantly increased in grade III ependymomas (p < 0.0001 for PI and p = 0.0015 for hTR). In these tumors, the PI and hTR expression were highly correlated (p = 0.0001). Of note, a single case designated grade II showed both increased proliferative activity and the highest hTR expression detected in this series of ependymal neoplasms. Our results suggest that the PI and hTR expression may be important biologic markers, independent of other histopathologic criteria of tumor grade. Future studies examining the correlation of MIB-1 cell kinetics and hTR expression with clinical parameters in selected ependymoma subtypes are needed to determine the prognostic relevance of these markers.

Volume

56

Issue

10

First Page

1142

Last Page

1146

ISSN

0022-3069

Disciplines

Medical Pathology | Pathology

PubMedID

9329458

Department(s)

Department of Pathology and Laboratory Medicine, Pathology Laboratory Medicine Faculty

Document Type

Article