ANXA2 and Patent ductus arteriosus: In this study, we demonstratethree new findings that elucidate the role of ANXA2 in PDA invasion and metastases.First, localization of ANXA2 expression on the cell surface is required for PDAinvasion in vitro and metastases formation invivo. Second, Tyr23-phosphorylation is required for localization of ANXA2on the PDA cell surface and subsequent PDA invasion and metastases formation.Importantly, knockdown of ANXA2 or inhibition with ANXA2 antibody therapy inhibitsthe metastatic process.