In a study using a MMTV-Ras transgenic mouse model of breast cancer, tumor formation was delayed and the number and tumor size of the primary tumor were lower, but a higher number of metastases were observed in MMP-11-deficient mice than in wild-type mice, indicating that MMP-11 promotes tumorigenesis in the early stages of breast cancer but inhibits the metastasis of tumor cells in the late stage of breast cancer (86). Here, MMP11 is linked to breast cancer.