Insulin-like Growth Factor 2

Insulinlike Growth Factor II, a 67aa mitogenic polypeptide and member of the Insulin gene family, synthesized by various foetal tissues during prenatal development, under the influence of placental lactogen. IGFII is a growth factor which exhibits both paracrine and autocrine properties and signals by binding to the type 1 and type 2 insulinlike growth factor receptors (type 1 IGFR and type 2 IGFR), and also to the insulin receptor (IR). The availability of IGFII is dependent upon its attachment to, and release from, various IGF binding proteins (IGFBPs), a relationship which has been investigated in breast cancer research (2).