Role of MMPs in metastatic dissemination: implications for therapeutic advances.

Matrix metalloproteinases (MMPs) have been implicated in both normal and pathologic processes. In cancer in particular, in vitro and animal studies showed an involvement of MMPs in many stages of cancer progression. This led to the development of MMP inhibitors that in most cases failed in clinical trials. In this review we go over the role of MMPs in the different stages of cancer progression and try to understand why the early generation of MMP inhibitors failed. The analysis of the lessons from this first experience, plus the review of the current knowledge that shows that MMPs may be pro-or anti-tumorigenic may set the stage for a future success for this therapeutic strategy in cancer.