Proposed model showing functional relationship between MTCBP-1 with MT1-MMP and invadopodia. In the absence of MTCBP-1, MT1-MMP is sequestered by F-actin at invadopodia to remodel the surrounding stroma through its proteolytic activity. Cells expressing high levels of MTCBP-1 facilitates its binding directly to residues PRR^568–570 of MT1-MMP and disrupts the association between MT1-MMP and F-actin, which occurs via adjacent residues 571–573 (LLY) on the CT of MT1-MMP. The result of this displacement is a reduction of functional invadopodia and attenuated tumor cell invasion.