Matrix metalloproteinase-7(MMP-7)also known as neutrophil collagenase and CLG1,is a member of matrix metalloproteinases (MMPs) family,which degrade components of the extracellular matrix (ECM) and play essential roles in various physiological processes as well as pathological processes. MMP-7 may affect the metastatic behavior of breast cancer cells through protection against lymph node metastasis, underlining the importance of anti-target identification in drug development. MMP-7 in the tumor may have a protective effect against lymph node metastasis.