Possible association of p53 codon 72 polymorphism with susceptibility to adult and pediatric high-grade astrocytomas

Abstract

Polymorphisms in codon 72 of the p53 tumor suppressor gene have been associated with susceptibility to human cancer. We wished to evaluate whether variant allelic forms of the p53 protein were associated with brain tumors. In this study, we scored 135 brain tumor samples (92 adult and 43 pediatric cases consisting of 64 high-grade astrocytomas and 71 non-astrocytomas) for the P53 Arg72Pro polymorphisms. Our data show that the genotype frequencies of P53 Arg72Pro vary not only between patients with brain tumors and controls, but also between different histological subtypes of brain tumors. Specifically, we found (i) that the genotype distributions of the P53 Arg72Pro between all brain tumors and controls were statistically significant ( P < 0.001) as well as their variant allele frequencies between cases and controls ( P < 0.001); (ii) that there was a significant increase in the Arg/Pro heterozygous genotype among high-grade astrocytomas compared with non-astrocytomas ( P = 0.002); and (iii) that there was a significant increase in the Arg/Pro heterozygous genotype among high-grade astrocytomas containing transdominant as well as recessive p53 mutations compared with controls ( P = 0.002). Our results suggest a possible association between P53 Arg72Pro polymorphisms and susceptibility to brain tumors, particularly high-grade astrocytomas.