Description
Insulin-like growth factor binding protein 7 (IGFBP7), also known as Mac25 and IGFBP-rp1, is a secretory protein. IGFBP7 is expressed in a wide range of normal human tissues with very high levels in HEVs of blood vessels in the secondary lymphoid tissues. IGFBP7 suppresses growth and colony formation of prostate and breast cancer cell lines through an IGF independent mechanism, which causes a delay in the G1 phase of the cell cycle and increased apoptosis. (1-2). The expression of IGFBP7 is upregulated in senescing epithelial cells and by retinoic acid (3). It plays a role in skeletal myogenesis by binding to IGF in a manner that inhibits IGF induced differentiation of skeletal myoblasts, without affecting IGF induced proliferation. IGFBP7 also interacts with heparin sulfate proteoglycans, type IV collagen and specific chemokines. It has also been implicated in angiogenisis