MMP-12 (Table 1), a metalloelastase that functions in the degradation of ECM elastin, as well as other ECM components (collagen IV, laminin, fibronectin, heparin, chondroitin sulfates, fibrillin-1 and others), is associated with solar elastosis after acute UV exposure, as well as with MM invasiveness and metastases (lymph node and distant metastases), which is regarded as a putative prognostic predictor [3,34]. This evidence concerns the gene ELN and Miyoshi myopathy.