For example, a previous report confirmed that quercetin exerts anti-cancer effects on a variety of tumour cells by regulating the phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR, Wnt/β-catenin, and MAPK/extracellular signal-regulated kinase 1/2 signalling pathways [26]. The gene discussed is MAPK3; the disease is cancer.