The role of apoptosis, cell proliferation index, bcl-2, and p53 in glioblastoma prognosis

Abstract

Glioblastoma is the most common neuroectodermic tumor. It is also the most malignant one. Many genetic changes are found in glioblastomas, among them, the presence of oncoproteins p53 and blc-2, as well as a high mitotic level and the presence of apoptosis. The utility of such findings through immunohistochemistry for the prognosis of patients remains uncertain. Our objectives in this study were to verify the presence of apoptosis, blc-2, p53, and the proliferative index (MIB-1), through immunohistochemistry, in 30 glioblastomas obtained by surgical resection between August 2000 and August 2001, as well as correlations between those immunohistochemical variables and the patient's age and survival time. Correlations between immunohistochemical variables themselves were also examined. For correlation calculations, Pearson's and Spermann's correlations were used and the time of survival was calculated with the Kaplan-Meier method. Results: No correlation was found between immunohistochemical variables and survival time. There was also no correlation between those variables and the patients' age. A moderate inverse correlation was found between the apoptotic index (AI) and the mitotic index (MI) (p = 0.058), besides an inverse correlation between blc-2 and MI. Conclusion: Our study has not demonstrated any of the examined immunohistochemical findings as having a predictive value in the prognosis of glioblastomas. A reverse correlation was found between AI and MI, which has already been demonstrated by a few studies, as well as an inverse correlation between blc-2 and MI. This finding can demonstrate blc-2 as having a pro-apoptotic role in this group of tumors.