Immunohistochemical expression of p53 and p21 in gliomas: a clinicopathological study

ABSTRACT

To evaluate p53 and p21 proteins over expression in gliomas and their relation to some clinico-pathological parameters. From September 2009 to July 2010, a formalin fixed, paraffin embedded blocks of 60 gliomas cases were collected in addition to 44 astrocytomas, 5 oligodendrogliomas, 2 oligoastrocytomas, and 9 ependymomas. These cases were evaluated by immunohistochemistry using streptavidin-biotin method. Overall, 53% of gliomas were positive for p53; these cases formed 66% of astrocytomas, 20% of oligodendrogliomas and 100% of oligoastrocytomas. In contrast to astrocytomas, all ependymoma cases were negative for p53 protein. There was a significant association of p53 expression with patient's age and tumor site. On the other hand, p21 expression was positive in 25% of gliomas; they comprised 23% of astrocytomas, 40% of oligodendrogliomas, 50% of oligoastrocytomas and 22% of ependymomas. Both p53 and p21 expressions seemed to be raising from low to high grades astrocytoma but they did not reach level of significance. The results of the present study suggest that p53 overexpression is common in gliomas and p21 expression is less common. There was a trend of both marker expressions increasing with higher grades