BackgroundMatrix metalloproteinases (MMPs) are multifunctional zinc-dependent proteinases that play a fundamental role in the pathogenesis of tumors. We have analyzed the association between 3 single-nucleotide polymorphisms (SNPs; MMP1 −1607 1G/2G, MMP3 −1612 5A/6A, and MMP9 −1562 C/T) and the risk of esophageal squamous cell carcinoma (ESCC).Material/MethodsWe investigated these 3 SNPs in 132 patients and 132 controls using polymerase chain reaction-restriction fragment length polymorphism methods. The MMP1 and MMP3 genes are located on the same chromosome. Haplotype analysis was performed to study the combined effect of the linked MMP polymorphisms on ESCC risk.ResultsThe MMP1 and MMP9 promoter polymorphisms were not associated with ESCC risk, while the MMP3 −1612 5A/6A polymorphism was significantly associated with susceptibility to ESCC. Patients carrying the 5A allele had a significantly higher risk for developing ESCC compared with individuals carrying the 6A allele (OR=1.93; 95% CI 1.34–2.77; p<0.01). The 2G-5A and 1G-5A haplotypes were associated with a significantly increased risk of ESCC as compared with the 2G-6A haplotype (OR=2.04, 95% CI 1.37–3.04 and OR=3.65, 95% CI 1.26–10.55, respectively).ConclusionsThese findings implicate this MMP3 polymorphism as a contributor to ESCC susceptibility.