Purpose: Matrix metalloproteinase-9 (MMP-9, gelatinase B) plays a key role in cancer invasion and metastasis by degradating the extracellular matrix (ECM) and basement membrane barriers. A cytosine (C)-thymidine (T) single nucleotide polymorphism (SNP) at position -1562 in the MMP-9 promoter is reported to affect expression of this gene. The purpose of this study was to investigate the relation between the -1562 C/T polymorphism and the development and progression of gastric cancer.
Methods: The study population included 177 gastric cancer patients and 224 healthy control subjects. The SNP in the MMP-9 promoter was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing. Genotype frequencies were compared between patients and controls, and the association of genotypes with clinicopathological features was studied.
Results: Genotype frequencies in gastric cancer patients were similar to those in control subjects (P = 0.223). However, significant association was found between degree of tumor invasion, clinical stage, and lymphatic invasion and the MMP-9 polymorphism in gastric cancer patients (P<0.05, for each).
Conclusions: Our results indicate that the T allele in the MMP-9 promoter is associated with the invasive phenotype of gastric cancer.