Expression of Bcl2 proto-oncogene in primary tumors of the central nervous system.

The present study was addressed to find out the expression of Bcl2 proto-oncogene in tumor tissues derived from 25 patients with primary central nervous system tumors. Brain parenchyma in 8 cases, with deeply located tumor, was also examined for Bcl2 expression which served as control. Both benign and malignant tumors (confirmed by histopathological examination) expressed Bcl2 gene product. Tumors exhibited 2-6 fold increase in Bcl2 expression as compared to the normal parenchyma adjacent to some of these tumors studied. However, no correlation was found between the histopathological types of tumor, glial fibrillary acidic protein positivity and degree of Bcl2 expression. Based on this study, we propose that the overexpression of Bcl2 gene product found in primary CNS tumors may be an important molecular event which is known to make the various types of tumor resistant to chemotherapy or radiotherapy.