STAT3 and cancer: Matrine was proven to inhibit SRC activity by non-competitively blocking the autophosphorylation of Tyr419 within the SRC domain, thereby inhibiting downstream phosphorylation levels of mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2 (MAPK/ERK), Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3), and PI3K/Akt signaling in cancer cells [222].