A candidate targeting molecule of insulin-like growth factor-I receptor for gastrointestinal cancers

Figure 4 The summary of strategies to inactivate type I insulin-like growth factor receptor system. (1) Inhibition of type I insulin-like growth factor receptor (IGF-IR) protein expression by blocking its translation [with antisense oligodeoxynucleotides and short interfering RNA (siRNA)]; (2) IGF-IR function can be blocked with inactivating monoclonal antibodies (mAb); (3) The tyrosine kinase activity of IGF-IR can be abolished with small-molecule inhibitors (TKI); (4) IGF-IR mutants lacking β-subunits can act as dominant-negative (dn) receptors; (5) Ligand availability can be reduced by mAb for IGFs; and (6) IGF binding proteins (IGFBPs) can reduce active forms of IGFs.