MMP14 and breast carcinoma: Taken together these analyses show that naturally increased MT1-MMP expression in transformed cancer cells (MDAMB-231, HS578t cells) does result in enhanced migration, but this is not the case for experimental MT1-MMP overexpression (MT1-MMP cell lines), as increasing overexpression of MT1-MMP decreases rather than enhances the migratory potential of breast cancer cells.