Genetic Variation in MMP-1 Promoter Region and Breast Cancer Susceptibility

Breast cancer forms from uncontrolled growth of abnormal breast cells, and its metastasis is one of the leading causes of death among women. MMP-1 is a member of matrix metalloproteinase genes family that is involved in many steps of cancer development and invasion. Genetic variation in the MMP-1 promoter (insertion or deletion of a Guanine) could modify the level of MMP-1 expression and taught to be a facile factor for tumor development and metastasis. The purpose of the present study is evaluation whether genetic variation in MMP-1 promoter could modify the susceptibility to development and metastasis of breast cancer. Therefore, it could be considered as genetic marker for identification highly prone women for breast cancer initiation and/or invasion. For investigation of this hypothesis, we genotyped 200 women with breast cancer and 100 control subjects without any history of genetic disease using PCR-RFLP. The median follow up of patients was 20 months. Metastasis based analysis revealed that 2G/2G genotype had stronger correlation with metastasis group than M- group; both at the time of diagnosis (OR=1.86, %95CI=1.0-3.64) and also at the end of follow-up duration (OR=2.71, %95CI=1.43-5.11). Our data suggest that 2G/2G homozygote polymorphism is involved in metastatic spread, but not in initiation of breast cancer.