STAT3 and head and neck squamous cell carcinoma: Another study was performed to examine the effects of EGCG on vascular endothelial growth factor (VEGF) production by YCU-H891 HNSCC and MDA-MB-231 breast carcinoma cell lines and results confirm the constitutive activation of the EGFR, Stat3, and Akt inhibited by the treatment with a major biologically active component of green tea, EGCG [50].