Analysis of 2 antiapoptotic factors in gliomas: bcl-2 overexpression and p53 mutations.
BACKGROUND
p53 mutations and immunoreactivity have been described in human gliomas. During the past few years, some authors have found bcl-2 overexpression in astrocytomas, although their correlation with histological grade is a matter of disagreement. A relation between bcl-2 overexpression and p53 immunoreactivity has also been suggested.


OBJECTIVE
To analyze the frequency of presentation of bcl-2 and p53, their clinicopathologic implications, and their possible coexpression.


METHODS
We studied p53 and bcl-2 with immunohistochemical and molecular methods in 61 gliomas (including 21 astrocytomas, 9 anaplastic astrocytomas, 29 glioblastomas, 1 oligodendroglioma, and 1 mixed glioma).


RESULTS
We discovered a high level of bcl-2 overexpression (57%). Overexpression of bcl-2 can be an early event in gliomas tumorigenesis, although no correlation was found with any of the clinicopathologic parameters studied. p53 mutations were present in a small proportion of gliomas (17%). p53 immunoreactivity was present in 34 cases (57%), and it was related to histological grade and a supratentorial location. A high percentage of tumors (26 cases, 42%) presented p53 immunoreactivity without p53 mutations.


CONCLUSIONS
Since there was no relation between bcl-2 overexpression and p53 mutations or p53 immunoreactivity, both factors may not act together in the genesis and evolution of gliomas.
Rodriguez-Pereira
C
C
Department of Pathology, Complejo Hospitalario Universitario de Santiago, Santiago, Spain. apimljsp@usc.es
Suarez-Peñaranda
J M
JM
Barros
F
F
Sobrido
M J
MJ
Vazquez-Salvado
M
M
Forteza
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D017209:Apoptosis; D001932:Brain Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002648:Child; D005260:Female; D015870:Gene Expression; D016158:Genes, p53 / Q000235:genetics*; D005910:Glioma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000235:genetics*; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53