PURPOSE Insulin-like growth factor (IGF) binding proteins (IGFBP) modulate interactions of IGF ligands with the IGF-I receptor. The role of IGFBPs, and specifically IGFBP-2, in breast cancer progression has been poorly defined. This study assesses the effect of IGFBP-2 on the behavior of human breast cancer using clinical specimens as well as in vitro and in vivo experimental systems. EXPERIM...

BACKGROUND Tumor-specific immunity of insulin-like growth factor-binding protein-2 (IGFBP-2) has been reported in several cancers. We aimed to assess the role of serum IGFBP-2 antibodies (IGFBP-2 Abs) in early cancer detection. PATIENTS AND METHODS Glioma and colorectal carcinoma (CRC) were used as models. Serum IGFBP-2 and IGFBP-2 Abs were measured in 260 tumor patients (145 gliomas, 45 colo...

Breast tumor cell lines have been shown to secrete at least five distinct insulin-like growth factor (IGF) binding proteins (IGFBP), the secretion being related to the estrogen receptor (ER) content. In this study we investigated IGFBP mRNA expression and IGFBP content in relation to ER content in human breast tumors. Tissue specimens from 47 breast cancers were studied. In five cases the adjac...

Insulin-like growth factor binding proteins (IGFBPs) are high-affinity binding partners for IGFs and play important roles in modulating IGF activities. In this study, we have identified and characterized two functional IGFBP-6 genes in zebrafish. Structural, phylogenetic, and comparative genomic analyses indicate that they are co-orthologs of the human IGFBP-6 gene. To gain insight into how the...

The insulin-like growth factor (IGF)-independent effects of insulin-like growth factor binding protein-3 (IGFBP-3) to effect cellular apoptosis have now been described in various cellular systems. IGFBP-3 mediates transforming growth factor-beta-induced apoptosis. Other growth-inhibitory and apoptosis-inducing agents such as tumor necrosis factor-alpha (TNF-alpha) and the tumor suppressor gene ...

The bioactivity of the growth hormone-insulin-like growth factor (IGF) system is reduced in Turner syndrome and may explain the reduction seen in final height. We compared levels of free and total IGF-I, immunoreactive and Western ligand blot IGF-binding protein (IGFBP)-3, and IGFBP-3 proteolysis in women with Turner syndrome (n = 23) before (T(B)) and during 6 mo treatment with 17beta-estradio...

Insulin-like growth factor (IGF)-binding proteins (IGFBPs) antagonize IGF and gonadotropin actions on granulosa cells. Human atretic follicles express IGFBP-2 in granulosa cells more strongly and contain higher levels of IGFBP-2 and IGFBP-4 than healthy follicles. We studied the effects of interferon-gamma (IFN gamma) and activin A, which decrease progesterone accumulation, on granulosa cell IG...

BACKGROUND IGFBP-3 is a multifunctional protein that inhibits growth and induces apoptosis of cancer cells. Hypermethylation of the promoter represses expression of the IGFBP-3 gene. We undertook this study to assess the impact of IGFBP-3 methylation on survival of early stage gastric cancer patients. METHODS Of the 482 tissue samples from gastric cancer patients who underwent curative surger...

Most patients treated with EGFR-tyrosine kinase inhibitors (EGFR-TKIs) eventually develop acquired resistance. Loss of expression of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) has been suggested as a possible mechanism of resistance to EGFR-TKIs in the A431 and HN11 cell lines. Here, we investigated IGFBP-3 expression in two EGFR mutant lung cancer cell lines with resistance t...

The objective of the present study was to evaluate changes in equine follicular fluid insulin-like growth factor binding protein (IGFBP) proteolytic activity as well as steroid, IGF, and IGFBP concentrations during follicular development in the mare. Mares (n = 14) were classified as either in the follicular phase (n = 8) or luteal phase (n = 6). Follicles (n = 92) were categorized as small (6 ...