P53 codon 72 Arg/Pro polymorphism and glioma risk: an updated meta-analysis

P53 codon 72 Arg/Pro is a C/G variation upstream of the p53 gene on human chromosome 17p13. Many case-control studies have investigated the association between p53 codon 72 Arg/Pro polymorphism and glioma risk but provided inconsistent findings. To better understand the pathogenesis of glioma, we performed the current meta-analysis by pooling data from all available individual studies. According to the inclusion criteria, ten independent publications with 11 case-control studies were included into this meta-analysis. The pooled odds ratio (OR) with 95 % confidence interval (95 % CI) was calculated to estimate the effect of p53 codon 72 Arg/Pro variant on the development of glioma. Overall, no appreciable correlation was observed among the total studies in all gene models (ORPro allele vs. Arg allele = 1.04, 95 % CI = 0.90-1.20, P (OR) = 0.581; ORPro/Pro vs. Arg/Arg = 0.95, 95 % CI = 0.80-1.14, P (OR) = 0.614; ORPro/Arg vs. Arg/Arg = 1.01, 95 % CI = 0.79-1.29, P (OR) = 0.993; ORPro/Arg + Pro/Pro vs. Arg/Arg = 1.03, 95 % CI = 0.82-1.29, P (OR) = 0.799; ORPro/Pro vs. Arg/Arg + Pro/Arg = 1.02, 95 % CI = 0.86-1.22, P (OR) = 0.785). In stratified analyses by ethnicity, source of controls, and glioma subtypes, the p53 codon 72 Arg/Pro polymorphism did not alter the risk for glioma in population-based, hospital-based, astrocytoma, and oligodendroglioma studies among Caucasian. Interestingly, the Pro/Pro genotype seemed to be negatively associated with the glioma risk among patients with glioblastoma (ORPro/Pro vs. Arg/Arg = 0.68, 95 % CI = 0.48-0.95, P (OR) = 0.026). Our study suggests that the polymorphism of p53 codon 72 Arg/Pro may play a protective role in the development of glioblastoma. The relationship of p53 codon 72 Arg/Pro polymorphism with the susceptibility to glioma needs further estimation by more individual studies with high quality across ethnicities.