SMAD3 and neoplasm: Pharmacological studies have found that quercetin inhibits tumor growth and induces tumor autophagy and apoptosis by regulating various signaling pathways, for instance, PI3K-Akt signaling pathway, NF-κB signaling pathway, mTOR signaling pathway, MAPK signaling pathway 80, TGF-β1/Smad3/c-MYC pathway 81, EGFR signaling pathway 82 and Jak-STAT signaling pathway 83.