Expression of bcl-2 in reactive and neoplastic astrocytes: Lack of correlation with presence or degree of malignancy

M. Krishna, T. W. Smith, L. D. Recht

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

The bcl-2 protooncogene encodes a 26-kD protein that extends cell survival by blocking apoptosis. This protein has been found to be overexpressed in neoplastic neural cell lines, although its expression in reactive and neoplastic astrocytes in vivo has not been well characterized. The authors hypothesized that bcl-2 oncoprotein expression in gliomas might be positively correlated with the tumor's degree of malignancy. Sixty-three gliomas of various subtypes and histological grades were immunostained by bcl-2 protein and the percentage of positive cells was quantitatively assessed. All tumors contained neoplastic cells that were immunoreactive for the bcl-2 protein (range of cell positivity 1%-53%). It was found that bcl-2 expression did not vary significantly as a function of tumor subtype or grade (p < 0.1, one-way analysis of variance (ANOVA) on ranks) as compared to the cell proliferation marker Ki-67 (MIB-1) in which a very significant correlation with tumor grade was noted (p < 0.0000001, one-way ANOVA on ranks). In fact, the highest percentage of bcl-2 immunoreactive cells was noted in low-grade gliomas, that is, in juvenile pilocytic astrocytomas and oligoastrocytomas. The specificity of bcl-2 overexpression was also assessed in 10 nonneoplastic lesions associated with prominent reactive astrocytosis. In nine of these cases (90%), bcl-2-positive reactive astrocytes were observed, often in large numbers, whereas relatively few Ki-67 immunoreactive cells were noted. The authors conclude that bcl-2 oncoprotein expression as assessed immunohistochemically does not correlate with glial tumor type or grade and its overexpression is not confined only to neoplastic conditions. Instead, the finding of robust bcl-2 expression in low grade glial tumors and in reactive astrocytes warrants the inference that resistance to apoptosis is a nonspecific finding in astrocytes associated with both reactive and neoplastic conditions.

Original languageEnglish (US)
Pages (from-to)1017-1022
Number of pages6
JournalJournal of Neurosurgery
Volume83
Issue number6
StatePublished - 1995
Externally publishedYes

Fingerprint

Astrocytes
Neoplasms
Glioma
Oncogene Proteins
Neuroglia
Analysis of Variance
Proteins
Apoptosis
Gliosis
Astrocytoma
Cell Survival
Cell Proliferation
Cell Line

Keywords

  • bcl-2
  • cell death
  • glioma
  • Ki-67
  • reactive gliosis

ASJC Scopus subject areas

  • Clinical Neurology
  • Neuroscience(all)

Cite this

Expression of bcl-2 in reactive and neoplastic astrocytes : Lack of correlation with presence or degree of malignancy. / Krishna, M.; Smith, T. W.; Recht, L. D.

In: Journal of Neurosurgery, Vol. 83, No. 6, 1995, p. 1017-1022.

Research output: Contribution to journalArticle

@article{37c1b8feffa84d7692e14ef20b5579bd,
title = "Expression of bcl-2 in reactive and neoplastic astrocytes: Lack of correlation with presence or degree of malignancy",
abstract = "The bcl-2 protooncogene encodes a 26-kD protein that extends cell survival by blocking apoptosis. This protein has been found to be overexpressed in neoplastic neural cell lines, although its expression in reactive and neoplastic astrocytes in vivo has not been well characterized. The authors hypothesized that bcl-2 oncoprotein expression in gliomas might be positively correlated with the tumor's degree of malignancy. Sixty-three gliomas of various subtypes and histological grades were immunostained by bcl-2 protein and the percentage of positive cells was quantitatively assessed. All tumors contained neoplastic cells that were immunoreactive for the bcl-2 protein (range of cell positivity 1{\%}-53{\%}). It was found that bcl-2 expression did not vary significantly as a function of tumor subtype or grade (p < 0.1, one-way analysis of variance (ANOVA) on ranks) as compared to the cell proliferation marker Ki-67 (MIB-1) in which a very significant correlation with tumor grade was noted (p < 0.0000001, one-way ANOVA on ranks). In fact, the highest percentage of bcl-2 immunoreactive cells was noted in low-grade gliomas, that is, in juvenile pilocytic astrocytomas and oligoastrocytomas. The specificity of bcl-2 overexpression was also assessed in 10 nonneoplastic lesions associated with prominent reactive astrocytosis. In nine of these cases (90{\%}), bcl-2-positive reactive astrocytes were observed, often in large numbers, whereas relatively few Ki-67 immunoreactive cells were noted. The authors conclude that bcl-2 oncoprotein expression as assessed immunohistochemically does not correlate with glial tumor type or grade and its overexpression is not confined only to neoplastic conditions. Instead, the finding of robust bcl-2 expression in low grade glial tumors and in reactive astrocytes warrants the inference that resistance to apoptosis is a nonspecific finding in astrocytes associated with both reactive and neoplastic conditions.",
keywords = "bcl-2, cell death, glioma, Ki-67, reactive gliosis",
author = "M. Krishna and Smith, {T. W.} and Recht, {L. D.}",
year = "1995",
language = "English (US)",
volume = "83",
pages = "1017--1022",
journal = "Journal of Neurosurgery",
issn = "0022-3085",
publisher = "American Association of Neurological Surgeons",
number = "6",

}

TY - JOUR

T1 - Expression of bcl-2 in reactive and neoplastic astrocytes

T2 - Lack of correlation with presence or degree of malignancy

AU - Krishna, M.

AU - Smith, T. W.

AU - Recht, L. D.

PY - 1995

Y1 - 1995

N2 - The bcl-2 protooncogene encodes a 26-kD protein that extends cell survival by blocking apoptosis. This protein has been found to be overexpressed in neoplastic neural cell lines, although its expression in reactive and neoplastic astrocytes in vivo has not been well characterized. The authors hypothesized that bcl-2 oncoprotein expression in gliomas might be positively correlated with the tumor's degree of malignancy. Sixty-three gliomas of various subtypes and histological grades were immunostained by bcl-2 protein and the percentage of positive cells was quantitatively assessed. All tumors contained neoplastic cells that were immunoreactive for the bcl-2 protein (range of cell positivity 1%-53%). It was found that bcl-2 expression did not vary significantly as a function of tumor subtype or grade (p < 0.1, one-way analysis of variance (ANOVA) on ranks) as compared to the cell proliferation marker Ki-67 (MIB-1) in which a very significant correlation with tumor grade was noted (p < 0.0000001, one-way ANOVA on ranks). In fact, the highest percentage of bcl-2 immunoreactive cells was noted in low-grade gliomas, that is, in juvenile pilocytic astrocytomas and oligoastrocytomas. The specificity of bcl-2 overexpression was also assessed in 10 nonneoplastic lesions associated with prominent reactive astrocytosis. In nine of these cases (90%), bcl-2-positive reactive astrocytes were observed, often in large numbers, whereas relatively few Ki-67 immunoreactive cells were noted. The authors conclude that bcl-2 oncoprotein expression as assessed immunohistochemically does not correlate with glial tumor type or grade and its overexpression is not confined only to neoplastic conditions. Instead, the finding of robust bcl-2 expression in low grade glial tumors and in reactive astrocytes warrants the inference that resistance to apoptosis is a nonspecific finding in astrocytes associated with both reactive and neoplastic conditions.

AB - The bcl-2 protooncogene encodes a 26-kD protein that extends cell survival by blocking apoptosis. This protein has been found to be overexpressed in neoplastic neural cell lines, although its expression in reactive and neoplastic astrocytes in vivo has not been well characterized. The authors hypothesized that bcl-2 oncoprotein expression in gliomas might be positively correlated with the tumor's degree of malignancy. Sixty-three gliomas of various subtypes and histological grades were immunostained by bcl-2 protein and the percentage of positive cells was quantitatively assessed. All tumors contained neoplastic cells that were immunoreactive for the bcl-2 protein (range of cell positivity 1%-53%). It was found that bcl-2 expression did not vary significantly as a function of tumor subtype or grade (p < 0.1, one-way analysis of variance (ANOVA) on ranks) as compared to the cell proliferation marker Ki-67 (MIB-1) in which a very significant correlation with tumor grade was noted (p < 0.0000001, one-way ANOVA on ranks). In fact, the highest percentage of bcl-2 immunoreactive cells was noted in low-grade gliomas, that is, in juvenile pilocytic astrocytomas and oligoastrocytomas. The specificity of bcl-2 overexpression was also assessed in 10 nonneoplastic lesions associated with prominent reactive astrocytosis. In nine of these cases (90%), bcl-2-positive reactive astrocytes were observed, often in large numbers, whereas relatively few Ki-67 immunoreactive cells were noted. The authors conclude that bcl-2 oncoprotein expression as assessed immunohistochemically does not correlate with glial tumor type or grade and its overexpression is not confined only to neoplastic conditions. Instead, the finding of robust bcl-2 expression in low grade glial tumors and in reactive astrocytes warrants the inference that resistance to apoptosis is a nonspecific finding in astrocytes associated with both reactive and neoplastic conditions.

KW - bcl-2

KW - cell death

KW - glioma

KW - Ki-67

KW - reactive gliosis

UR - http://www.scopus.com/inward/record.url?scp=0029621163&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029621163&partnerID=8YFLogxK

M3 - Article

C2 - 7490615

AN - SCOPUS:0029621163

VL - 83

SP - 1017

EP - 1022

JO - Journal of Neurosurgery

JF - Journal of Neurosurgery

SN - 0022-3085

IS - 6

ER -