Disease relevance of IGFBP3

• Recently, insulin-like growth factor-binding protein-3 (IGFBP-3) has been reported to be phosphorylated by breast cancer cell membranes [1].

High impact information on IGFBP3

• The inhibitors of TG2, cystamine and monodansyl cadaverine, abolished the ability of the T47D cell membrane preparation to phosphorylate IGFBP-3 [1].
• Porcine ovarian cells express messenger ribonucleic acids for the acid-labile subunit and insulin-like growth factor binding protein-3 during follicular and luteal phases of the estrous cycle [2].
• IGFBP-3 mRNA was equally expressed in granulosa cells of all growing follicles [2].
• In thecal cells, expression of mRNA for IGFBP-3, ALS and cyclin D1 (a marker of cell proliferation) was restricted to healthy (aromatase-expressing) follicles [2].
• It has recently been shown that, in follicular fluid, as in the circulation, insulin-like growth factors (IGFs)-I and -II exist in a ternary complex with IGF binding protein-3 (IGFBP-3) and the acid-labile subunit (ALS) [2].

Biological context of IGFBP3

• A DraI RFLP at the porcine insulin-like growth factor binding protein 3 (IGFBP3) gene [3].
• The GHRHR and IGFBP3 were found to map near to each other on human chromosome 7 (HSA7), and the pig IGFBP3 gene has been mapped to SSC18 by others [4].
• Mapping of HOXA11, INHBA, and IGFBP3 on pig Chr 18 constitutes the first assignments of genes on this small chromosome [5].
• Additionally, at least one of the IGFBPs, IGFBP-3, has been shown to have IGF-independent effects on cell proliferation [6].
• After ovulation, IGFBP-3 mRNA was moderately expressed in granulosa luteins but strongly detected in a few theca-derived cells and in vascular endothelial cells [2].

Anatomical context of IGFBP3

• Insulin-like growth factor binding protein-3 mRNA was not detectable in fibroblast cultures either before or after TGF beta-1 treatment [7].
• Divergent actions of prostaglandins-E2 and -F2 alpha on the regulation of insulin-like growth factor-binding protein-3 in luteinized granulosa cells [8].
• Numerous studies have shown that immortalized muscle cell lines produce various IGFBPs, but to date no muscle cell line has been reported to produce IGFBP-3 protein or mRNA [6].
• This study demonstrates that follicular fluid IGFBP-3 and ALS, like the IGFs, originate (at least in part) from the ovary [2].
• Results suggest that alterations in IGFBP-3 mRNA and protein may play a role in differentiation of porcine embryonic muscle cells [6].

Associations of IGFBP3 with chemical compounds

• This study demonstrated that PGE2 and PGF2 alpha conversely modulate IGFBP-3 production [8].
• In contrast to the effects of IGFBP-3, PGE2 stimulated progesterone production to 8-fold of control (P < 0.05) while PGF2 alpha had no effect [8].
• The purpose of the present study was to examine the effects on IGFBP-3 production of prostaglandin (PG)-E2, a compound known to stimulate luteal function and prevent/delay luteal regression (a luteotropic compound), and PGF2 alpha, a compound known to be luteolytic [8].
• On the other hand, the different patterns of action of GH and IGF-I on OT, estrogen and IGFBP-3 suggest that part of the GH effect on ovarian cells is IGF-I independent [9].
• GH (10 ng/ml or above) was able to inhibit androstenedione, OT, PGF and IGFBP-3, to stimulate IGF-I and cAMP, and to alter testosterone and PGE release by follicles cultured in serum-supplemented and/or serum-free medium [9].

Analytical, diagnostic and therapeutic context of IGFBP3

• Muscle-derived fibroblasts secreted no detectable IGFBP-3 but approximately 10 times more IGFBP-2 than did myogenic cell cultures [7].
• We studied IGFBP-3 and ALS messenger RNA (mRNA) by in situ hybridization [2].
• The immunoprecipitates retained IGFBP-3 kinase, whereas immunoprecipitation deleted kinase activity in the membrane supernatant [1].
• We purified the IGFBP-3 kinase activity from solubilized T47D breast cancer cell membranes using gel filtration, ion-exchange chromatography, and IGFBP-3 affinity chromatography [1].

References