LOX (lysyl oxidase) is a secreted copper-dependent amine oxidase and a member of the lysyl oxidase family . It primarily catalyzes the oxidation of lysine (or hydroxylysine) residues in collagen and elastin to form peptidyl aldehyde derivatives . These modifications are required for further cross-linking of target proteins to enhance ECM (extracellular matrix) stiffness. LOX plays critical roles in vascular, lung, and skin development, and tissue damage repair . Upregulation of LOX is associated with various diseases, including cancer progression and tissue fibrosis. Aberrant LOX activity creates a favorable tumor microenvironment to promote tumor metastasis and distal colonization .