Gastric cancer metastasis-associated genes, including hypoxia-inducible factor (HIF)-1α, matrix metalloproteinase (MMP)-2, MMP-9, basic fibroblast growth factor (bFGF), and urease plasminogen activator (uPA) were measured by RT-sqPCR prior to and following transfection with the KAI1 gene. Here, MMP9 is linked to gastric cancer.