Expression of BCL-2 oncoprotein on tumor cells and tumor-infiltrating lymphocytes (TIL) in meningiomas.
The Expression of the antiapoptotic oncoprotein BCL-2 and its correlation to tumor grade in 62 meningiomas (48 classic, 9 atypical, and 5 anaplastic) using single and double immunohistochemistry was investigated. BCL-2 expression was found in two different cell populations identified as lymphocytes (BCL-2+CD3+) and tumor cells (BCL+/CD3-). Tumor-infiltrating lymphocytes (TIL) (CD3+) were found within classic (9.5% of cells), atypical (2.4% of cells), and anaplastic (1.8% of cells) meningiomas. In classic meningiomas, 66.5% of TIL were BCL-2-positive, in atypical meningiomas 79.2%, and in anaplastic meningiomas 37.9%. In 33 (68.8%) of the classic meningiomas, medium to high counts of BCL-2+ tumor cells were detected. Atypical meningiomas showed nearly equal percentages of high (two patients), medium (five patients), and low (two patients) BCL-2+ tumor cell counts, whereas anaplastic meningiomas showed only medium (two patients) and low (three patients) BCL-2 tumor cell counts or were BCL-2-negative (one patient). In summary, a significant inverse correlation between the number of BCL-2-positive tumor cells and tumor grade in meningiomas was found. These findings support the hypothesis of cell survival prolongation by the antiapoptotic ability of BCL-2 proto-oncogenes and demonstrate the prognostic relevance of BCL-2 immunoreactivity in meningiomas.
Roessler
K
K
Department of Neurosurgery, University Hospital of Vienna, Austria.
Dietrich
W
W
Kitz
K
K
D017252:CD3 Complex / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D016246:Lymphocytes, Tumor-Infiltrating / Q000378:metabolism*; D008577:Meningeal Neoplasms / Q000378:metabolism* / Q000473:pathology; D008579:Meningioma / Q000378:metabolism* / Q000473:pathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*
D017252:CD3 Complex; D019253:Proto-Oncogene Proteins c-bcl-2