In humans, tissue metalloproteinase inhibitor 4 (TIMP-4) is a protein encoded by the TIMP4 gene in the tissue metalloproteinase inhibitor family. There are four members of the family, TIMP-1, TIMP-2, TIMP-3 and TIMP-4. Of the four known members of the TIMP family, TIMP-4 has features common to all TIMPs and its own unique features. Unlike TIMP-2, TIMP-4 does not promote the activation of MMP-2 precursors through activated MMP-14(MT1-MMP). TIMP-4 mRNA is expressed at high levels in the heart and at low levels in the kidneys, pancreas, colon and testis. TIMP-4 is expressed in breast cancer, cervical cancer, endometrial cancer, glioma and choriocarcinoma.