A non-IGF binding mutant of IGFBP-3 modulates cell function in breast epithelial cells
Section snippets
Materials and methods
Materials. Insulin-like growth factor-I (IGF-I) was purchased from Gropep (Adelaide, Australia). An IGF-I receptor antagonist (IGFIR-AT) was purchased from Immunological and Biochemical Testsystems (IBT) GmbH (Reutlingen, Germany). The IGFIR-AT is a peptide that inhibits the autophosphorylation of the IGF-IR and has been shown to inhibit the proliferation of a number of cell lines in a dose-dependent manner [22]. Non-glycosylated (ng) IGFBP-3 was a gift from Dr. C.A. Macck (Celtrix
Effects of IGFBP-3 on C2-induced apoptosis in IGF-non-responsive Hs578T cells
In the Hs578T cell line, C2 induced a significant (P<0.05) increase in cell death from 10.5% to 23.8% whereas ng, gly, or mut IGFBP-3 alone had no effect in comparison to controls. As demonstrated previously [9], we confirmed that ng IGFBP-3 was able to significantly (P<0.05) accentuate C2-induced cell death from 23.8% to 47.3%. We now demonstrate further that gly and mut IGFBP-3 can similarly (P<0.05 for each) enhance C2-induced cell death from 23.8% to 44.1% and 40.2%, respectively (Fig. 1A).
Discussion
We have demonstrated in the Hs578T IGF non-responsive cell line that like ng IGFBP-3, gly, and mutant IGFBP-3 can also accentuate C2-induced cell death in an IGF-independent manner. Having established that the non-IGF binding mutant of IGFBP-3 maintained its intrinsic actions on cell death, we then examined the effects of this mutant in the IGF responsive MCF-7 and MCF10-A cell lines. We determined in the MCF-7 cell line that IGFBP-3 had no effect on C2-induced death, whereas in the MCF-10A
Acknowledgements
We wish to thank the Association for International Cancer Research and the Needham Cooper Trust for supporting this work.
References (39)
Cell death: the significance of apoptosis
Int. Rev. Cytol.
(1980)Insulin-like growth factor binding proteins
Vitam. Horm.
(1993)- et al.
Insulin-like growth factor binding protein-3 induces apoptosis in MCF7 breast cancer cells
Biochem. Biophys. Res. Commun.
(1997) - et al.
Insulin-like growth factor IGF-independent action of IGF-binding protein-3 in Hs578T human breast cancer cells. Cell surface binding and growth inhibition
J. Biol. Chem.
(1993) - et al.
Transforming growth factor-beta-induced cell growth inhibition in human breast cancer cells is mediated through insulin-like growth factor-binding protein-3 action
J. Biol. Chem.
(1995) - et al.
Insulin-like growth factor (IGF)-binding protein-3 induces apoptosis and mediates the effects of transforming growth factor-beta1 on programmed cell death through a p53- and IGF-independent mechanism
J. Biol. Chem.
(1997) - et al.
Demonstration of receptors for insulin-like growth factor binding protein-3 on Hs578T human breast cancer cells
J. Biol. Chem.
(1993) - et al.
Oncogenic ras causes resistance to the growth inhibitor insulin-like growth factor binding protein-3 (IGFBP-3) in breast cancer cells
J. Biol. Chem.
(1999) - et al.
Insulin-like growth factor-binding protein (IGFBP)-3 and IGFBP-5 share a common nuclear transport pathway in T47D human breast carcinoma cells
J. Biol. Chem.
(1998) - et al.
Direct functional interactions between insulin-like growth factor-binding protein-3 and retinoid X receptor-alpha regulate transcriptional signaling and apoptosis
J. Biol. Chem.
(2000)
Substitutions for hydrophobic amino acids in the N-terminal domains of IGFBP-3 and -5 markedly reduce IGF-I binding and alter their biologic actions
J. Biol. Chem.
Insulin-like growth factor-binding protein IGFBP-3 predisposes breast cancer cells to programmed cell death in a non-IGF-dependent manner
J. Biol. Chem.
Insulin-like growth factor binding protein (IGFBP) proteolysis: occurrence, identification, role and regulation
Growth Horm. IGF Res.
Prostate carcinoma (PC-3) cell proliferation is stimulated by the 22–25-kDa proteolytic fragment (1–160) and inhibited by the 16-kDa fragment (1–95) of recombinant human insulin-like growth factor binding protein-3
Growth Horm. IGF Res.
Growth inhibition by insulin-like growth factor-binding protein-3 in T47D breast cancer cells requires transforming growth factor-beta (TGF-beta) and the type II TGF-beta receptor
J. Biol. Chem.
Insulin-like growth factors and their binding proteins: biological actions
Endocr. Rev.
IGF binding protein-3 and the acid-labile subunit: formation of the ternary complex in vitro and in vivo
Adv. Exp. Med. Biol.
Insulin-like growth factor I (IGF-I)-binding protein complex is a better mitogen than free IGF-I
Endocrinology
Insulin-like growth factor (IGF) binding protein from human decidua inhibits the binding and biological action of IGF-I in cultured choriocarcinoma cells
Endocrinology
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