bcl-2 protein expression in astrocytomas in relation to patient survival and p53 gene status

• Published in: Acta neuropathologica 1997-10, Vol.94 (4), p.369-375
• Main Authors: NEWCOMB, E. W, BHALLA, S. K, PARRISH, C. L, HAYES, R. L, COHEN, H, MILLER, D. C
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Astrocytes; Astrocytoma; Astrocytoma - genetics; Astrocytoma - metabolism; Astrocytoma - mortality; Astrocytoma - pathology; Bcl-2 protein; Biological and medical sciences; Brain Neoplasms - genetics; Brain Neoplasms - metabolism; Brain Neoplasms - mortality; Brain Neoplasms - pathology; Central nervous system; Child; Child, Preschool; Female; Gene Expression; Genes, p53; Humans; Immunohistochemistry; Male; Malignancy; Medical prognosis; Medical sciences; Middle Aged; Neoplasm Staging; Neurology; p53 Protein; Patients; Pediatrics; Prognosis; Protein expression; Proteins; Proto-Oncogene Proteins c-bcl-2 - biosynthesis; Survival Rate; Tumor cells; Tumors; Tumors of the nervous system. Phacomatoses
• ISSN: 0001-6322; 1432-0533
• DOI: 10.1007/s004010050721

bcl-2 protein expression was characterized in a series of 58 astrocytomas from 21 pediatric and 37 adult patients. As part of a continuing attempt to define relevant prognostic factors which may predict clinical outcome, we have determined the impact of bcl-2 accumulation in malignant astrocytes on the length of patient survival. Aberrant overexpression of bcl-2 protein in tumor cells was detected in 57% (12 of 21) of pediatric and 73% (27 of 37) of the adult cases. Among pediatric patients, the median survival in months showed no relationship with the incidence of bcl-2-positive tumors. Among the adult patients, a favorable prognostic indicator was low-tumor grade (P = 0.05). bcl-2-positive tumors occurred with similar frequencies in WHO grades III and IV of malignancy. When bcl-2 expression in tumor cells was tested as a variable to predict for patient survival, the 6 patients without bcl-2 expression among 23 adult patients with grade IV tumors had a shorter median survival. The same 58 tumors had been previously analyzed for alterations of p53:4 pediatric and 16 adult tumors had p53 gene mutations. There was no significant difference in median survival related to p53 gene status. There was no relationship between bcl-2 expression and p53 gene status: approximately equal numbers of tumors with either wild-type or mutant p53 were bcl-2 negative or bcl-2 positive. bcl-2 expression is high (40-100%) among other tumors of the central nervous system which also show low malignant potential. Up-regulation of bcl-2 in malignant astrocytes or constitutive expression in some tumor types may be a factor leading to a more favorable clinical outcome.