The MMP-1, MMP-2, and MMP-9 gene polymorphisms and susceptibility to bladder cancer: a meta-analysis

The relationship between matrix metalloproteinase (MMP) polymorphisms and bladder cancer risk has become a hot topic and was studied extensively in recent years, but the results are still controversial. In order to estimate the relationship of MMP polymorphisms and the risk of bladder cancer, we performed this meta-analysis. We conducted a comprehensive search of databases; PubMed, Web of Science, Embase, Chinese Biomedical Literature Database (CBM, Chinese) and Wanfang Database (Chinese) were searched for all case-control studies which mainly study the relationship between MMP-1-1607 1G/2G, MMP-2-1306 C/T, and MMP-9-1562 C/T polymorphisms and the susceptibility of bladder cancer. The association between the MMP polymorphisms and bladder cancer risk was conducted by odds ratios (ORs) and 95% confidence intervals (95% CIs). At last, totally five literatures with 1,141 cases and 1,069 controls were contained in the meta-analysis. Among these articles, four articles with 1,103 cases and 1,053 controls were about MMP-1-1607 1G/2G polymorphism and three studies with 839 cases and 775 controls for MMP-2-1306 C/T polymorphism and MMP-9-1562 C/T polymorphism. With regard to MMP-1-1607 1G/2G polymorphism, significant association was found with bladder cancer susceptibility only under recessive model (2G2G vs. 1G2G/1G1G: OR = 1.44, 95% CI = 1.05-1.97, P = 0.022), and as to the MMP-2-1306 C/T polymorphism, significant association was found with bladder cancer susceptibility only under homozygote model (TT vs. CC: OR = 2.10, 95% CI = 1.38-3.10, P = 0), but no associations was found between MMP-9-1562 C/T polymorphism and bladder cancer susceptibility. The results suggest that the MMP-2-1306 C/T and MMP-9-1562 C/T polymorphisms are significantly associated with bladder cancer susceptibility, and no associations were found between MMP-9-1562 C/T polymorphism and bladder cancer susceptibility.