Abstract
The detection of IGF-IR signaling in animal models has important implications for
determining the role of this receptor in normal physiology and tumor growth. While
many reports have correlated changes in plasma IGF-I levels in vivo with biological responses, few have shown that altered IGF-I levels can directly
affect signaling within normal or tumor tissue. Here, we present new data that shows
how the intravenous (IV) injection of IGF-I can be used to directly examine IGF signaling
at the tissue level. Tail-vein IV injection of IGF-I into mice resulted in a rapid
and dose-dependent activation of the IGF-I receptor and downstream phosphorylation
of Akt and ERK1/2 in liver, kidney, and mammary gland. Similarly, IV IGF-I rapidly
stimulated signaling in HT-29 colorectal and in MCF-7 breast cancer xenografts. This
study shows how IV IGF injection can be used to examine the signaling mechanisms used
by IGF-IR, in both normal mammary tissue and during tumor growth, and may provide
a model for the characterization of IGF inhibitors.
Key words
IGF-I - Mammary gland - Kidney - Liver - Xenografts - Signal transduction
References
- 1
Baserga R, Morrione A.
Differentiation and malignant transformation: two roads diverged in a wood.
J Cell Biochem.
1999;
Suppl
68-75
- 2
Dupont J, LeRoith D.
Insulin and insulin-like growth factor I receptors: similarities and differences in
signal transduction.
Horm Res.
2001;
55 Suppl 2
22-26
- 3
Surmacz E.
Growth factor receptors as therapeutic targets: strategies to inhibit the insulin-like
growth factor I receptor.
Oncogene.
2003;
22
6589-6597
- 4
Butler A A, Yakar S, LeRoith D.
Insulin-like growth factor-I: compartmentalization within the somatotropic axis?.
News Physiol Sci.
2002;
17
82-85
- 5
Wu Y, Yakar S, Zhao L, Hennighausen L, LeRoith D.
Circulating insulin-like growth factor-I levels regulate colon cancer growth and metastasis.
Cancer Res.
2002;
62
1030-1035
- 6
Yakar S, Liu J L, Fernandez A M, Wu Y, Schally A V, Frystyk J, Chernausek S D, Mejia W,
LeRoith D.
Liver-specific igf-1 gene deletion leads to muscle insulin insensitivity.
Diabetes.
2001;
50
1110-1118
- 7
Chang P Y, Goodyear L J, Benecke H, Markuns J S, Moller D E.
Impaired insulin signaling in skeletal muscles from transgenic mice expressing kinase-deficient
insulin receptors.
J Biol Chem.
1995;
270
12 593-12 600
- 8
Cui X, Zhang P, Deng W, Oesterreich S, Lu Y, Mills G B, Lee A V.
Insulin-Like Growth Factor-I Inhibits Progesterone Receptor Expression in Breast Cancer
Cells via the Phosphatidylinositol 3-Kinase/Akt/Mammalian Target of Rapamycin Pathway:
Progesterone Receptor as a Potential Indicator of Growth Factor Activity in Breast
Cancer.
Mol Endocrinol.
2003;
17
575-588
- 9
Lee A V, Zhang P, Ivanova M, Bonnette S, Oesterreich S, Rosen J M, Grimm S, Hovey R C,
Vonderhaar B K, Kahn C R, Torres D, George J, Mohsin S, Allred D C, Hadsell D L.
Developmental and hormonal signals dramatically alter the localization and abundance
of insulin receptor substrate proteins in the mammary gland.
Endocrinol.
2003;
144
2683-2694
- 10
Kleinberg D L, Feldman M, Ruan W.
IGF-I: an essential factor in terminal end bud formation and ductal morphogenesis.
J Mammary Gland Biol Neoplasia.
2000;
5
7-17
- 11
Lee A V, Hilsenbeck S G, Yee D.
IGF system components as prognostic markers in breast cancer.
Breast Cancer Res Treat.
1998;
47
295-302
- 12
Dominici F P, Hauck S, Argentino D P, Bartke A, Turyn D.
Increased insulin sensitivity and upregulation of insulin receptor, insulin receptor
substrate (IRS)-1 and IRS-2 in liver of Ames dwarf mice.
J Endocrinol.
2002;
173
81-94
- 13
Li M, Li C, Parkhouse W S.
Differential effects of des IGF-1 on Erks, AKT-1 and P70 S6K activation in mouse skeletal
and cardiac muscle.
Mol Cell Biochem;.
2002;
236
115-122
- 14
Di Cola G, Cool M H, Accili D.
Hypoglycemic effect of insulin-like growth factor-1 in mice lacking insulin receptors.
J Clin Invest.
1997;
99
2538-2544
- 15
Saad M J, Araki E, Miralpeix M, Rothenberg P L, White M F, Kahn C R.
Regulation of insulin receptor substrate-1 in liver and muscle of animal models of
insulin resistance.
J Clin Invest.
1992;
90
1839-1849
- 16
Giddings S J, Carnaghi L R.
Insulin receptor gene expression during development: developmental regulation of insulin
receptor mRNA abundance in embryonic rat liver and yolk sac, developmental regulation
of insulin receptor gene splicing, and comparison to abundance of insulin-like growth
factor 1 receptor mRNA.
Mol Endocrinol.
1992;
6
1665-1672
- 17
Kjeldsen T, Andersen A S, Wiberg F C, Rasmussen J S, Schaffer L, Balschmidt P, Moller K B,
Moller N P.
The ligand specificities of the insulin receptor and the insulin-like growth factor
I receptor reside in different regions of a common binding site.
Proc Natl Acad Sci USA.
1991;
88
4404-4408
- 18
Rubini M, D’Ambrosio C, Carturan S, Yumet G, Catalano E, Shan S, Huang Z, Criscuolo M,
Pifferi M, Baserga R.
Characterization of an antibody that can detect an activated IGF-I receptor in human
cancers.
Exp Cell Res.
1999;
251
22-32
- 19
Firth S M, Baxter R C.
Cellular actions of the insulin-like growth factor binding proteins.
Endocr Rev.
2002;
23
824-854
- 20
Bar R S, Clemmons D R, Boes M, Busby W H, Booth B A, Dake B L, Sandra A.
Transcapillary permeability and subendothelial distribution of endothelial and amniotic
fluid insulin-like growth factor binding proteins in the rat heart.
Endocrinol.
1990;
127
1078-1086
- 21
Walton P E, Gopinath R, Burleigh B D, Etherton T D.
Administration of recombinant human insulin-like growth factor I to pigs: determination
of circulating half-lives and chromatographic profiles.
Horm Res.
1989;
31
138-142
- 22
Luetteke N C, Qiu T H, Fenton S E, Troyer K L, Riedel R F, Chang A, Lee D C.
Targeted inactivation of the EGF and amphiregulin genes reveals distinct roles for
EGF receptor ligands in mouse mammary gland development.
Development.
1999;
126
2739-2750
A. V. Lee, Ph. D.
Breast Center · Room N1110 · Baylor College of Medicine
One Baylor Plaza · MS:600 · Houston · TX 77030
Phone: + 1 (713) 798-1624
Fax: + 1 (713) 798-1642
Email: avlee@breastcenter.tmc.edu