LOXL3 (lysyl oxidase-like 3) is a copper-dependent amine oxidase that catalyzes protein-lysine 6-oxidase activity, playing a critical role in extracellular matrix (ECM) cross-linking of collagen and elastin 1. Beyond its enzymatic function, LOXL3 exhibits diverse biological roles including fibronectin oxidation in myotendinous junction formation, STAT3 deacetylation in inflammatory response regulation, and participation in epithelial-mesenchymal transition (EMT) 1. Pathologically, LOXL3 contributes to fibrosis progression through ECM cross-linking 2, though its individual contribution relative to other LOX family members remains incompletely understood. In cancer, LOXL3 demonstrates a "dual personality": it promotes proliferation, migration, and invasion in multiple cancer types including melanoma, gastric, pancreatic, and bladder cancers through interactions with EMT transcription factors like SNAIL1 and PRRX1 3, while simultaneously influencing immune microenvironments and checkpoint responses relevant to immunotherapy efficacy 4. Clinically, autosomal recessive LOXL3 variants cause Stickler syndrome with severe myopia, cleft palate, and progressive retinal degeneration, reflecting its essential role in collagen homeostasis during development 56. LOXL3 represents a promising therapeutic target in multiple disease contexts.