title: Correlation of bcl-2, p53, and MIB-1 expression with ependymoma grade and subtype.
abstract: In this study, we report our results on the proliferative activity of ependymomas as determined by MIB-1 (also known as Ki-67) immunohistochemical analysis, and we compare our results with those obtained by immunolabeling with monoclonal antibodies to p53 and bcl-2 proteins to assess whether expression correlated with ependymoma subtype or tumor grade. The study included 4 myxopapillary ependymomas (Grade I of the World Health Organization [WHO] scale), 10 subependymomas (WHO Grade I), 17 ependymomas (WHO Grade II), 2 papillary ependymomas (WHO grade II), and 4 anaplastic ependymomas (WHO Grade III). The MIB-1 proliferation index was significantly higher in tumors diagnosed as anaplastic ependymoma (P < .001), with a moderate level of correlation (Kendall's tau-b = 0.557, asymptotic standard error = 108). In addition, one ependymoma (WHO Grade II) not considered overtly anaplastic by routine histologic criteria showed a high MIB-1 labeling index, suggesting that the MIB-1 proliferation index might be a more objective indicator of tumor grade. The remaining WHO Grade I and Grade II ependymomas showed low proliferative activity. bcl-2 oncoprotein expression was identified in all of the four myxopapillary and in both papillary ependymomas. An additional observation was the correlation of p53 expression with increasing WHO grade. These data suggest that high MIB-1 and p53 immunolabeling might be objective indicators of high grade in ependymomas that do not otherwise meet routine histologic criteria for high-grade ependymoma. Subsequent clinicopathologic analyses will be important in assessing whether these markers are useful as independent predictors of survival.
authors.affiliation: Department of Pathology, University of Texas Southwestern Medical School, Dallas, USA. ERUSHI@mednet.swmed.edu
authors.forename: E J
authors.initials: EJ
authors.lastname: Rushing
authors.forename: D F
authors.initials: DF
authors.lastname: Brown
authors.forename: C L
authors.initials: CL
authors.lastname: Hladik
authors.forename: R C
authors.initials: RC
authors.lastname: Risser
authors.forename: B E
authors.initials: BE
authors.lastname: Mickey
authors.forename: C L
authors.initials: CL
authors.lastname: White
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D034961:Antigens, Nuclear; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology; D004806:Ependymoma / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D013120:Spinal Cord Neoplasms / Q000378:metabolism* / Q000473:pathology; D013194:Staining and Labeling; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D034961:Antigens, Nuclear; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53