title: Biology of insulin-like growth factor binding protein-4 and its role in cancer (review).
abstract: Insulin-like growth factor binding protein-4 (IGFBP-4) is an important member of the insulin-like growth factor (IGF) system. The IGFBP-4 has three domains of which the N-terminal sequence is important for the binding of IGF. It acts as a transport protein for IGF-I and IGF-II and modulates their biological effects. There is increasing evidence that IGFBP-4 inhibits IGF-induced cellular growth both in vitro and in vivo. IGFBP-4 can also mediate its actions through a mechanism independent of IGFs. IGFBP-4 level and expression in various tissues are influenced by IGFBP protease, nutrition, several growth factors and hormones. Overexpression of IGFBP-4 in transgenic animal models causes reduced growth of organs containing smooth muscle. Most cancers express IGFBP-4 at levels which correlate with their state of differentiation. However, the effects of IGFBP-4 on tumor growth are uncertain. In vitro studies have shown that overexpression of IGFBP-4 inhibit the growth of some colon cancer cells. Overexpression of IGFBP-4 in vivo has been reported to decrease the growth of prostate cancer. The effect of altered expression of IGFBP-4 in vivo in colon and other cancers needs to be explored as locally available IGFs appear to stimulate mitogenesis.
authors: University Department of Surgery, Royal Free and University College Medical School, University College London, London, UK.
authors: Rajaraman
authors: R
authors: Durai
authors: Mark
authors: M
authors: Davies
authors: Wenxuan
authors: W
authors: Yang
authors: Shi Yu
authors: SY
authors: Yang
authors: Alexander
authors: A
authors: Seifalian
authors: Geoffrey
authors: G
authors: Goldspink
authors: Marc
authors: M
authors: Winslet