Currently, we revealed that exosomes derived from YB-1 transfected GC cells (SGC-7901 LV-YBX1) could establish the premetastatic niche by inhibiting the apoptosis and promoting the motility of human umbilical vein endothelial cells (HUVECs), with increased mRNAs and proteins of intracellular VEGF, Ang-1, MMP-9 and IL-8 observed. This evidence concerns the gene MMP9 and gastric cancer.