Current Evidence on the Association between Four Polymorphisms in the Matrix Metalloproteinases (MMP) Gene and Breast Cancer Metastasis

Abstract

The matrix metalloproteinases (MMP) can degrade various components of the extracellular matrix and its functional genetic polymorphisms may be associated with cancer metastasis. However, this relationship remains inconclusive in breast cancer. To better understand the roles of MMP polymorphisms in breast cancer metastasis, we conducted this comprehensive meta-analysis encompassing 1,165 cases and 3,418 controls. Four polymorphisms including MMP1 (-1607 1G/ 2G), MMP2 (-1575 G.A), MMP3 (1612 5A/6A), and MMP9 (-1562 C.T) were studied in this meta-analysis. Crude odds ratios (OR) with 95% confidence intervals (CI) were used to assess the strength of association. We found significant association between MMP1 (-1607 1G/2G) and breast cancer metastasis (for the recessive model 2G/2G vs. 1G/2G+1G/1G: OR 1.81, 95% CI 1.32–2.48; for the dominant model 2G/2G+1G/2G vs. 1G/1G: OR 1.60, 95% CI 1.02– 2.50). For the MMP3, significant association between MMP3 (-1171 5A/6A) and breast cancer metastasis was also detected under the dominant model (6A/6A+5A/6A vs. 5A/5A: OR 0.55, 95% CI 0.37-0.80). In conclusion, our results demonstrate that MMP1 may contribute the risk of breast cancer metastasis, while MMP3 played a protective role in breast cancer metastasis. Further studies are needed to evaluate these associations with breast cancer metastasis.