Background: Lumican,a class Ⅱ small leucine-rich proteoglycans,have been designated key roles in extracellular matrix organization.Increasing number of evidence shows that Lumican,as an important modulator of biological functions,suppresses angiogenesis.We tested its effects on angiogenesis in vitro and vasculogenesis in vivo and roles on the control of biological behavior of human umbilical vein endothelial cells (HUVEC).