With this work we want to challenge the long-standing view that MMPs, particularly MT1-MMP, exert their role in cancer progression as proteases that predominately degrade ECM components to allow cancer cell invasion, and instead suggest a subtle role for MT1-MMP in tumour progression as metastatic cancer appears to be better represented by low levels of inhibited MT1-MMP protein. Here, MMP14 is linked to metastatic malignant neoplasm.