LOXL4 and hepatocellular carcinoma: The 2-fold enrichment in exosomes in the LOX family interactome suggests that ECM cross-linking by hypoxic endothelial cell-derived exosomes mediated by LOXL2 [57], and exosome-mediated secretion of LOXL4 promoting hepatocellular carcinoma cell invasion and metastasis [15] might involve other members of the family and their partners.