[Collagenases and cancers].

We analyze here recent data from literature concerning the role of collagenases in cancer. The alteration of basement membrane (BM) and extracellular matrix components, in particular collagens, has been widely reported during tumor invasion. The collagenases degrade interstitial collagens (types I and III) and BM collagens (type IV). So, they break natural barriers and allow tumor cells to spread in surrounding tissues and metastasize. Classical collagenases are not able to degrade type IV collagen (the main component of BM) which, however, often appears to be very altered around tumor cells. Therefore, the existence of a specific type IV collagenase is necessary to explain this phenomenon. Most studies performed with the object of proving the role of collagenases in tumor invasion and metastasis have shown the presence of a type I collagenase, but type IV collagenase has been more difficult to evidence.