HSPG2 and cancer: Indeed, besides angiopoietin-like 6, a number of extracellular proteins share similarity with the metastasis-specific peptides, among which a proteoglycan (perlecan) and a component of the basal lamina (laminin α2), both involved in angiogenesis and cancer progression (Theocharis et al, 2010; Vitolo et al, 2006).