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The matrix metalloproteinase-21 gene 572C/T polymorphism and the risk of breast cancer.

BACKGROUND
Matrix metalloproteinases (MMPs) contribute in multiple ways to all stages of tumor development, and a number of DNA polymorphisms in the MMP genes are associated with an increased risk of cancer. We previously identified the MMP-21 gene 572C/T polymorphism leading to Ala191Val substitution within the enzyme's catalytic domain. We performed a case-control study to test association between this polymorphism and the risk of breast cancer.


PATIENTS AND METHODS
572C/T polymorphism was analyzed by RFLP method in 396 unrelated Russian females: 76 breast cancer patients and 320 disease-free blood donors.


RESULTS
The frequencies of C/C, T/C and T/T genotypes in patients (69.7%, 25.0% and 5.3%) did not differ significantly from those in controls (61.9%, 34.7% and 3.4%); the polymorphism was not associated with the increased tumor size and the presence of metastases.


CONCLUSION
The MMP-21 gene 572C/T polymorphism has no significant effect on the development and progression of breast cancer.