P53 and PCNA expression in benign, atrypical and malignant meningiomas

ABSTRACT

OBJECTIVE: Alterations p53 genes are turning out to be the most common genetic alterations in human cancers. Due to long half-life of mutated p53, its detection is possible by immunohistochemistry. Proliferating cell nuclear antigen [PCNA] is expressed by dividing cells, hence has been shown to correlate with prognosis. We have used monoclonal antibodies protein DO-7 [p53] and PC10 [PCNA] to see whether their expression correlates with histological grading in meningethelial tumour. MATERIAL AND METHODS: Twenty nine meningiomas [20 benign, 7 atypical and 2 malignant] were selected from the records of our laboratory. p53 and PCNA expression was sought by immunohistochemistry using Peroxidase Anti Peroxidase [PAP] technique. Four benign and 2 atypical meningiomas showed weak staining for p53. Both malignant meningiomas showed strong positivity for p53. Six benign meningiomas had less than 5% PCNA positivity, one 10% positivity and three showed 20% positivity. PCNA positivity ranged for 10-80% in atypical meningiomas. In two malignant meningiomas PCNA positivity was 70% and 90%. It is worthwhile to include p53 and PCNA expression along with histologic assessment in predicting outcome of meningiomas. A larger series with complete follow-up is essential in assessing value of these markers which unfortunately remains a dream in our country