Abstract

In an attempt to evaluate expression of p53 and to characterize the role af p53 alterations in pathogenesis and progression of gliomas, 49 tumors were immunostained with monoclonal antibodies against p53, TGF-a, PCNA on archival formalin-fixed, paraffin-embedded materials. The tumors were divided into low-grade(19 cases) and high-grade(30 cases) gliomas. We evaluated whether expression of these proteins are associated with differentiation of the tumor, and analyzed correlations among these proteins. The results are summarized as follows. The overall incidence of p53 expression in 49 gliomas was 49%(24/49). The extent of p53 immunolabelling of tumor ce11s increased from low-grade to high-grade tumors(p=0.002, Chi-Square Score): Low-grade tumors revealed 21 %(4/19) immunoreactivity, whereas, 67%(20/30) reactivity was seen in high-grade ones. A significant correlation between p53 and TGF-a expression was demonstrated(p=0.024). A correlation between expression of p53 and PCNA revealed borderline significance(p=0.064). The results suggest that p53 could be a useful independent prognostic indicator in human gliomas, possibly in combination with TGF-a and PCNA. And also, the results support the hypothesis that p53 mutations play a role in the progression from low-grade to high-grade gliomas.

• Keywords: p53, TGF-a, PCNA, Immunohistochemical study, Gliomas