p53 point mutation is rare in meningiomas from Singaporean patients

In Asian populations, meningiomas account for up to 35% of all central nervous system tumours, a significantly higher incidence than in Caucasian populations. While several studies have examined p53 both at the level of the gene and the protein in both benign and malignant meningiomas, its role remains controversial, particularly with regard to the discrepancy between p53 over-expression and gene mutation. We examined 19 benign meningiomas, all of which were known to over-express p53, and eight malignant meningiomas, of which three were known to over-express p53, for mutations in the p53 gene using polymerase chain reaction amplification and direct sequencing of exons 4 to 9, inclusive. Only one single mutation was detected in a benign meningioma, confirming that p53 over-expression in meningiomas is commonly found in the absence of gene mutations, and that despite the significantly higher incidence of meningiomas in some Asian populations, this is not associated with a significantly higher rate of p53 mutations.