IGFBP ratio confers resistance to IGF targeting and correlates with increased invasion and poor outcome in breast tumors.

ABSTRACT:

Purpose

To improve the significance of insulin-like growth factor-binding protein 5 (IGFBP-5) as a prognostic and potentially predictive marker in patients with breast cancer.

Experimental design

Increased IGFBP-5 expression was identified in MCF-7 cells resistant (MCF-7R4) to the IGF-1R/insulin receptor (InsR) inhibitor BMS-536924 and its role examined by targeted knockdown and overexpression in multiple experimental models. Protein expression of IGFBP-5 was measured by immunohistochemistry in a cohort of 76 patients with breast cancer to examine correlative associations with invasive tumor fraction and outcome. The use of a combined IGFBP-5/IGFBP-4 (BPR) expression ratio was applied to predict anti-IGF-1R/InsR response in a panel of breast cancer lines and outcome in multi

SUBMITTER: Becker MA 

PROVIDER: S-EPMC3306532 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature