Finally, an abnormal balance between elevated proteolysis activity with increased P-selectin (Gotting et al., 2008), matrix metallo-proteinase (MMP) 2 and 9 (Diekmann et al., 2009), suggests an abnormal remodeling of the extra cellular matrix (ECM) in PXE. This evidence concerns the gene SELP and pseudoxanthoma elasticum (inherited or acquired).