Figure 1.

Targeted RTK and their signal transduction routes in head and neck cancer. The EGFR, Met, and IGF-1R receptors and their prototypic ligands are shown. Cysteine-rich domains (red box) and fibronectin type III-like domain (grey box) are indicated in the extracellular domains of the EGFR and IGF-1R, respectively. Cytoplasmic tyrosine kinase domains for each receptor are indicated (green boxes). The symbols α and β denote distinct RTK subunits. Targeted humanized monoclonal antibodies for extracellular components (white box) and TKIs (black box) for each receptor signaling axis is shown.