Objective          To investigate the role of microRNA-126 (miR-126) on regulation of vascular endothelial growth factor (VEGF) mediated angiogenesis. Methods       Human umbilical vein endothelial cells (HUVECs) were cultured and transfected with lentiviral vectors carrying miR-126. The cells were divided into control group，empty vector group and miR-126 transfected group (LV3-miR-126). Total RNAs were collected at day 6 after transfection. The mRNA expression of negative regulatory factors

sprouty related EVH1 domain containing 1 (spred1) and phosphoinositide-3kinase regulatory subunit 2 (Pik3R2)

were measured by quantitative realtime polymerase chain reaction （qRT-PCR）. The protein expression of spred1 and Pik3R2 was detected by Western blot.  Results      The qRT-PCR results showed that spred1 and Pik3R2 were significantly down-regulated in LV3-miR126 group compared with the control and empty vector groups (P0.05).  Also

their protein expression levels were obviously decreased with statistical significance (P0.05). Conclusion      miR-126 expression can promote proliferation of endothelial cells and VEGF-mediated angiogenesis.