It can also activate other members of the MMP family,[10] induce angiogenesis,[5] and enhance cell metastasis.[11] At present, it is speculated that MMP-14 leads to bone invasion of cholesteatoma through the following ways: Activation of MMP-2: MMP-2 is type IV collagenase, which can degrade laminin and fibronectin of basement membrane. This evidence concerns the gene MMP2 and cholesteatoma.