The association between matrix metalloproteinase-7 genetic variant and bladder cancer risk in a Chinese Han population

The circulating matrix metalloproteinase-7 (MMP-7) levels are associated with the risk of bladder cancer (BC). MMP-7 gene -181A/G polymorphism may influence the expression of MMP-7 by affecting the transcriptional activity. A case-control study comprising 355 BC patients and 435 age- and gender-matched healthy controls was conducted in a Chinese Han population. The genotype of MMP-7 gene -181A/G polymorphism was determined by using polymerase chain reaction-restriction fragment length polymorphism method. Data revealed that MMP-7 gene -181A/G polymorphism increased the risk of BC under the homozygous and allelic models. However, no association between MMP-7 gene -181A/G polymorphism and BC risk was obtained after adjusting for age, gender, smoking habits and drinking habits. Subgroup analyses showed MMP-7 gene -181A/G polymorphism was associated with increased risk for BC among the smokers and drinkers. Furthermore, AG or GG genotype of -181A/G polymorphism was associated with larger tumor size and lymphatic metastasis in BC patients. To sum up, MMP-7 gene -181A/G polymorphism is not associated with the susceptibility to BC. However, subgroup analyses obtain significant association among the groups of smokers and drinkers. Larger studies in other ethnic groups are needed to ascertain the contribution of MMP-7 gene -181A/G polymorphism to BC risk.