Importantly, MMP2, MMP9 and MMP14 are enriched at the invadopodia and are required for cancer metastasis (Ala-aho and Kahari, 2005; Bjorklund and Koivunen, 2005; Hofmann et al., 2005; Kerkela and Saarialho-Kere, 2003; Lochter et al., 1998; Mook et al., 2004; Wagenaar-Miller et al., 2004). Here, MMP9 is linked to cancer.