Prognostic factors in astrocytomas: relationship of p53, MDM-2, BCL-2 and PCNA immunohistochemical expression to tumor grade and overall patient survival.

The immunohistochemically detected expression of p53, BCL-2, MDM-2 and PCNA proteins in samples of tumor tissues of 42 patients with astrocytomas or glioblastoma multiforme was statistically compared to degree of malignancy and overall survival. We found relation between p53 protein expression and survival in the high grade astrocytomas group (more cases of p53 immunonegative tumors with longer survival), and significantly higher BCL-2 protein expression as well as significantly higher MDM-2 protein expression in the group of low grade astrocytomas. PCNA protein expression showed any relation to tumor grade or survival. Despite the rather small number of samples these results support the hypothesis that MDM-2 protein may be a potent regulator of functional p53, expressed in low grade astrocytoma only.