igfbp การใช้

• Hypoglycosylated IGFBP-3 may be seen after extended glucose starvation.
• Dysregulation of IGFBP-3 has been implicated in many cancers.
• In contrast, human hepatocytes do express IGFBP-3.
• However, IGFBP-3 gene expression in human liver is GH-independent.
• Proteins of the matrix metalloproteinase ( IGFBP ), and activates MMP9 by cleavage.
• IGF-1 binds to IGFBP-3 in a 1 : 1 molar ratio.
• The mechanisms regulating these contrasting effects of IGFBP-3 in vivo are not well understood.
• IGFBP-3 serves to prolong the action of IGF-1 in the human body.
• IGFBP-3, the most abundant protein, accounts for 80 % of all IGF binding.
• IGFBP-3 was first isolated, characterized, and quantitated in human plasma, in 1986.
• The serum proteins transferrin, fibronectin, and plasminogen are also known to bind IGFBP-3.
• IGFBP-3 shares with the other five high-affinity IGFBPs and a 3-domain structure:
• Rat liver IGFBP-3 mRNA is found in nonparenchymal cells including sinusoidal endothelium, but not in hepatocytes.
• Immunoassays for serum IGFBP-3 are often used as part of the diagnosis of childhood GH-deficiency.
• However, instead of the full length, functional protein, IGFBP-3 is found to be cleaved.
• IGFBP-3 can enter cells by both clathrin-mediated and caveolin-mediated endocytosis . possibly involving the transferrin receptor.
• IGFBP-3 is still made ( at a lower level ) by prostate cancer cells and secreted into the surrounding environment.
• IGFBP-3 enters the cell nucleus by a mechanism that is incompletely understood, but involves its binding to importin-?.
• In some studies circulating IGFBP-3 also appears to be nutritionally regulated, although this may not be seen at the mRNA level.
• IPLEX ( Mecasermin rinfabate ) is composed of recombinant human IGF-1 ( rhIGF-1 ) and its binding protein IGFBP-3.