Emerging therapies in gastrointestinal cancers

Figure 2 Schematic representations of different ErbBs/EGFRs ligand-induced signaling pathways leading to development and progression of tumors. BTC: betacellulin; EGF: Epidermal growth factor; EGFR: Epidermal growth factor receptor; ERK: Extracellular signal regulated protein kinase; HB-EGF: heparin binding-EGF; Grb: Growth factor receptor receptor binding protein; JNK: c-Jun N-Terminal kinase; MEK: Mitogen activated protein kinase kinase; NDF: neu differentiation factors (also called neuregulins); PI3K: Phosphoinositide-3-kinase; PKB: Protein kinase B; SOS: Son of sevenless;TGF-α: transforming growth factor α.