An updated meta-analysis of the p53 codon 72 polymorphism and gastric cancer risk

To investigate the association between p53 codon 72 polymorphisms and gastric cancer risk, a meta-analysis published in 2007 was updated with new data. Relevant literature was retrieved by searching PubMed and statistical analysis conducted using Review Manager software. Twenty-eight case–control studies were included in this meta-analysis, with 6,859 cases and 9,277 controls. The pooled results for all included studies showed that patients with gastric cancer had a borderline lower frequency of the Arg/Arg phenotype (odds ratio (OR) = 0.91, 95 % CI = 0.83–1.00, p = 0.04). When stratified for race, the difference in Arg/Arg frequency was significant among Asians (OR = 0.87, 95 % CI = 0.78–0.97, p = 0.01). On stratifying the various studies we found that, among Asians: (i) patients with cardial gastric cancer had a significantly higher frequency of the Pro/Pro genotype (OR = 1.35, 95 % CI = 1.03–1.77, p = 0.04) than those with non-cardial gastric cancer; (ii) patients with advanced (stage III/IV) gastric cancer had a significantly higher frequency of Arg/Arg (OR = 1.30, 95 % CI = 1.06–1.61, p = 0.01) than those with early (stage I/II) cancer; and (iii) patients with metastasis had a significantly higher frequency of Pro/Pro (OR = 3.31, 95 % CI = 1.31–8.41) than those without metastasis. Our study suggests that, among Asians, the p53 codon 72 Arg/Arg genotype is associated with a modestly decreased risk of gastric cancer, and that this difference in genotype distribution may be associated with cancer stage, location, differentiation and metastasis.