Antibody mediated blockage of matrix metalloproteinase 9 (MMP9) stops breast cancer metastases in mouse model

Metastasis is the principal cause of cancer-related death and has traditionally been viewed as a late-occurring process during cancer progression.  Researchers from UCSF (San Francisco) and the Weizmann Institute of Science (Rehovot, Israel) found that MMP9 is an important component of metastasis early in tumorigenesis and promotes circulating tumor cells to colonize the lungs.

In a mouse model of breast cancer, the authors found that blocking active MMP9, using a monoclonal antibody inhibited lung metastases.  The inhibition of MMP9 attenuated migration, invasion, and colony formation and promoted CD8+ T cell infiltration and activation.  Interestingly, primary tumor burden was unaffected, suggesting a role for MMP9 specific to an early phase of metastasis.

This research suggests that metastases may be disrupted early on by inhibiting active MMP9 and suggesting that a MMP9-targeted anti-metastatic breast cancer therapy may be a viable therapeutic direction to stop breast cancer metastasis.