Insulin-like growth factor-binding protein 7 (IGFBP7) is a member of the IGFBP family. It has been identified in colorectal adenocarcinoma (CRC) cell lines. The Insulin-like growth factor-binding protein also known as IGFBP serves as a carrier protein for Insulin-like growth factor 1. IGFBPs are distinct but are sharing regions with strong homology. All members of the IGFBP family bind IGF-I and IGF-II with about equal affinity. Insulin-like growth factor (IGF) binding proteins (IGFBPs) have been shown to either inhibit or enhance the action of IGF or act in an IGF-independent manner in the prostate. IGFBP7 could inhibit cell growth, decrease soft agar colony formation activity, and induce apoptosis in RKO and SW620 cells. There is mounting evidence that the structure of the IGFBP proteins plays a key role in the regulation of IGF bioavailability, by modulating its molecular size, capillary membrane permeability, target tissue specificity, cell membrane adherence, and IGF affinity.

> 95 % as determined by SDS-PAGE.