Knocking-down MEG3 with a nano-polymer wrapped MEG3 short hairpin RNA (shRNA) plasmid conjugated with OX26 antibody (MPO) enhanced endothelial cells migration, tube formation in vitro and reduced the volume of cerebral infarction, capillary density, cerebral cortex micro-vessel in vivo by increasing the angiogenesis associated genes VEGFA and VEGFR (33). The gene discussed is MPO; the disease is brain infarction.