Figure 3: (a) Summary of TGF-α/EGFR/ras-MAPK activation loop in HNSCC (for more detail see Figure 2). (b) Inhibitory effect of EGCG on EGFR activation. EGCG alters organization of lipid rafts and promotes internalization of nonactivated monomer EGFR into cytosol through phosphorylation of EGFR at serine 1046/1047 by p38MAPK. As a result, EGCG causes a marked reduction of phosphorylated EGFR and thereby inhibits EGFR signaling that is prominent in HNSCC.