CHANGES IN INSULIN-LIKE GROWTH-FACTOR-I RECEPTOR EXPRESSION AND BINDING-PROTEIN SECRETION ASSOCIATED WITH TAMOXIFEN RESISTANCE AND ESTROGENINDEPENDENCE IN HUMAN BREAST-CANCER CELLS IN-VITRO

Citation
D. Mccotter et al., CHANGES IN INSULIN-LIKE GROWTH-FACTOR-I RECEPTOR EXPRESSION AND BINDING-PROTEIN SECRETION ASSOCIATED WITH TAMOXIFEN RESISTANCE AND ESTROGENINDEPENDENCE IN HUMAN BREAST-CANCER CELLS IN-VITRO, Cancer letters, 99(2), 1996, pp. 239-245
Citations number
22
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Oncology
Journal title
ISSN journal
0304-3835
Volume
99
Issue
2
Year of publication
1996
Pages
239 - 245
Database
ISI
SICI code
0304-3835(1996)99:2<239:CIIGRE>2.0.ZU;2-W
Abstract
Conditioned medium from a series of human breast cancer cell lines rep resenting the phenotypes of estrogen dependence (ZR-75-1, MCF-7), tamo xifen resistance (21R-75-9a1, LY2) and estrogen independence (ZR-PR-LT ) contained four detectable insulin-like growth factor binding protein s (IGFBPs) of MW 24, 34, 44 and 70 kDa. In the tamoxifen resistant lin es secretion of the 24 kDa IGFBP was depressed in comparison to the pa rent lines whilst secretion of the 44 kDa IGFBP was unaffected. Secret ion of this species by ZR-PR-LT cells was reduced. Following incubatio n in medium containing 1% serum both tamoxifen resistant cell lines se creted higher levels of the 44 kDa IGFBP than the respective parent li nes. These changes in IGFBP secretion associated with the development of tamoxifen resistance and estrogen independence were accompanied by changes in the expression of receptors for IGF-I.