Relation of the IGF/IGF1R system to autophagy in colitis and colorectal cancer

Figure 1 The IGF/IGF1R axis: schematic representation of the composition and function. Signaling of the IGF/IGF1R axis is mediated by IRS and Shc. PI3K-AKT activation is the predominant downstream event, but the Ras/MEK/ERK and JNK/MAPK pathways can also be activated. IGF: Insulin-like growth factor; IGF1R: Insulin-like growth factor receptor 1; IRS: Insulin receptor substrate; PI3K: Phosphatidylinositol-3-kinase; AKT: Serine/threonine kinase, named protein kinase B (PKB); mTOR: Mammalian target of rapamycin; Bad: Bcl-2-associated death promoter; Bcl2: B-cell lymphoma 2; Shc: Adaptor protein; Ras: GTPase protein; JNK: c-Jun N-terminal kinase; MEK: Mitogen-activated protein kinase kinase; ERK: Extracellular regulated kinase; MAPK: Mitogen-activated protein kinase; ELK: ETS domain-containing protein.