The predictive power of MMP/RKIP expression ratio for breast cancer relapse-free survival is apparently MMP type-specific as high MMP10 and low RKIP expression did not associate with poor survival S1 Fig These results implicate RKIP as a possible repressor of MMP13 expression in breast cancers and suggest that RKIP and MMP13 may be in the same regulatory pathway affecting cancer metastasis. This evidence concerns the gene MMP10 and breast cancer.