FIGURE 6.

IGF-1R activation network with substantial effector molecules. PI3K/PKB and MAPK/Ras are two regulatory cascades that can be triggered by IGF-1R. Cell death, glucose utilization, and protein production are all improved by PI3K/PKB. MAPK/Ras involves a complex kinase pathway that, in response, promotes the expression of transcription factors, i.e., ELK1 to accelerate cellular proliferation, angiogenesis, invasion, and metastasis. IGF binding proteins (IGFBPs) regulate the action of IGF ligands by direct interaction in the outer membrane environment. IGFBPs potentially have a variety of IGF actions due to their direct interactions with integrins.