The insulin-like growth factor binding protein BP-25 is expressed by human breast cancer cells. Academic Article uri icon

Overview

abstract

  • Specific binding proteins are thought to modulate the effects of IGF-I. Previous work has demonstrated that media conditioned by human breast cancer cells contains IGF-I binding activity. Radiolabelled IGF-I incubated with serum-free conditioned media from the breast cancer cell line MDA-MB 231 eluted with an apparent M.W. of 35-40 kDa when analyzed by gel filtration chromatography at pH 7.4. The M.W. of this binding activity corresponded to that of BP-25, a binding protein cloned from the hepatocellular carcinoma cell line HepG2. Two breast cancer cell lines, MDA-MB 231 and Hs578T, were found to express BP-25 RNA. Specific BP-25 radioimmunoassay detected BP-25 production in the conditioned media of these two cell lines. Immunoprecipitation confirmed that metabolically labelled MDA-MB 231 released 30 kDa BP-25 into its medium. This study demonstrates that some breast cancer cells express the IGF-I binding protein, BP-25.

authors

  • Rosen, Neal
  • Yee, D
  • Favoni, R E
  • Lupu, R
  • Cullen, K J
  • Lebovic, G S
  • Huff, K K
  • Lee, P D
  • Lee, Y L
  • Powell, D R
  • Dickson, R B

publication date

  • January 16, 1989

Research

keywords

  • Breast Neoplasms
  • Carrier Proteins
  • Insulin-Like Growth Factor I
  • Somatomedins

Identity

Scopus Document Identifier

  • 0024489917

Digital Object Identifier (DOI)

  • 10.1016/s0006-291x(89)80173-1

PubMed ID

  • 2463838

Additional Document Info

volume

  • 158

issue

  • 1