AB265. Association between MDM2 SNP309T>G polymorphism and the risk of bladder cancer: new data in Chinese population and an update meta-analysis

BACKGROUND: MDM2 is a mainly negative regulator of p53 tumor suppressor pathway. We aimed to investigate evaluate the association between MDM2 SNP309 polymorphism and bladder cancer risk. METHODS: A total of 535 bladder cancer patients and 649 health controls were recruited for our study. MDM2 SNP309 T>G polymorphism was genotyped by PCR-LDR method. Logistic regression was used to analyze the relationship between the genotype and susceptibility of bladder cancer. Kaplan-Meier estimates and log rank test were obtained to analyze the association between the genotype and risk of recrudesce in NMIBC patients. A multivariable Cox proportional hazards model was fitted to identify independent prognostic factors. To further investigate the association, we conducted a meta-analysis including six studies. RESULTS: The frequency of the MDM2 SNP309 T>G polymorphism showed no significant difference between cases and controls (all P>0.05). In the stratification analysis, the results showed that G allele carriers were prone to have a significant decrease in risk of low-grade bladder cancer (adjusted OR: 0.613, 95% CI: 0.427–0.881), and G-variant was associated with a significant reduced risk of recurrence in NMIBC patients with or without chemotherapy (P<0.05). The results of mate-analysis showed that G allele and GG genotype of MDM2 SNP309 polymorphism were significant associate with increased risk of bladder cancer in Caucasians (both P<0.05), and no association was observed in total populations and Asians (P<0.05). CONCLUSIONS: MDM2 SNP309T>G polymorphism has no influence on bladder cancer risk in Asians, but this SNP may be associated with genetic susceptibility of bladder cancer among Caucasians.