Expression of telomerase RNA component correlates with the MIB-1 proliferation index in ependymomas

Elisabeth J. Rushing, Kazuo Yashima, Daniel F. Brown, Charles L. White, Jerry W. Shay, Richard C. Risser, Adi F. Gazdar

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)1142-1146
Number of pages5
JournalJournal of neuropathology and experimental neurology
Issue number10
StatePublished - Oct 1997


  • Ependymoma
  • MIB-1
  • Proliferation index
  • Telomerase

ASJC Scopus subject areas

  • General Medicine


Dive into the research topics of 'Expression of telomerase RNA component correlates with the MIB-1 proliferation index in ependymomas'. Together they form a unique fingerprint.

Cite this