Quercetin inhibited the metastasis of gastric cancer cells by inhibiting urokinase plasminogen activator (uPA)/uPA receptor (uPAR) function through the regulation of nuclear factor kappa B (NF-kB), protein kinase C (PKC), extracellular signal-regulated kinases 2 and 3, and AMPK [125]. This evidence concerns the gene PLAU and gastric cancer.