TY - JOUR
T1 - Proliferation of cultured human prostate cancer cells is inhibited by insulin-like growth factor (IGF) binding protein-1
T2 - Evidence for an IGF-II autocrine growth loop
AU - Figueroa, Jose A.
AU - Lee, Adrian V.
AU - Jackson, James G.
AU - Yee, Douglas
PY - 1995/12
Y1 - 1995/12
N2 - In this study, we examined the expression of insulin-like growth factor (IGF) ligands, receptors (IGFR1, IGFR2), and binding proteins (IGFBPs) in the human prostate cancer cell line DU145, as well as its mitogenic response to the IGFs. Using RNase protection assays, we found expression of IGF-II, IGFR1, and IGFR2 but failed to detect IGF-I messenger RNA. Distinct binding protein species as well as immunoreactive IGF-II were detected in conditioned media using radioligand and immunoblotting assays. Compared with controls, treatment with exogenous IGF-I and IGF-II resulted in stimulation of monolayer and anchorage-independent growth. Recombinant human IGFBP-1, which binds IGF-II with high affinity, inhibited IGF-II-induced monolayer growth and both baseline and IGF-II-induced anchorage independent growth in this cell line. Our data suggest IGF-II is as an autocrine growth factor in DU145 cells, and that inhibition of IGF-II-dependent growth of human prostate cancer cells may represent a new therapeutic strategy for this disease.
AB - In this study, we examined the expression of insulin-like growth factor (IGF) ligands, receptors (IGFR1, IGFR2), and binding proteins (IGFBPs) in the human prostate cancer cell line DU145, as well as its mitogenic response to the IGFs. Using RNase protection assays, we found expression of IGF-II, IGFR1, and IGFR2 but failed to detect IGF-I messenger RNA. Distinct binding protein species as well as immunoreactive IGF-II were detected in conditioned media using radioligand and immunoblotting assays. Compared with controls, treatment with exogenous IGF-I and IGF-II resulted in stimulation of monolayer and anchorage-independent growth. Recombinant human IGFBP-1, which binds IGF-II with high affinity, inhibited IGF-II-induced monolayer growth and both baseline and IGF-II-induced anchorage independent growth in this cell line. Our data suggest IGF-II is as an autocrine growth factor in DU145 cells, and that inhibition of IGF-II-dependent growth of human prostate cancer cells may represent a new therapeutic strategy for this disease.
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U2 - 10.1210/jc.80.12.3476
DO - 10.1210/jc.80.12.3476
M3 - Article
C2 - 8530586
AN - SCOPUS:0028804261
SN - 0021-972X
VL - 80
SP - 3476
EP - 3482
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 12
ER -