Expression and synthesis of insulin-like growth factor-binding proteins in human glioma cell lines

Int J Oncol. 1998 Jan;12(1):129-35. doi: 10.3892/ijo.12.1.129.


We previously demonstrated the presence of insulin-like growth factors (IGFs) and IGF-receptors in human glioma cell lines derived from primary glioblastomas. The biological action of IGFs is modulated by specific IGF-binding proteins (IGFBP)-1 to -7. By means of polymerase chain reaction (PCR), we detected mRNA transcripts for IGFBP-1 in 42%, IGFBP-2 in 65%, IGFBP-3 in 97%, IGFBP-4 in 3%, IGFBP-5 in 74%, IGFBP-6 in 94% and IGFBP-7 in 87% of the glioma cell lines. The specificity of the PCR reaction was verified by direct sequencing of the PCR product. In addition, the content of the most prevalent IGFBP-3 was measured in conditioned medium from glioma cells by specific radioimmunoassay with levels ranging from < 1 to 620 ng/ml. Moreover, the presence of membrane-bound IGFBPs (44, 50 and 60 kDa) as well as IGF-II receptors was demonstrated by using 125I-labelled IGF-II as a ligand. In conclusion, IGFBPs may modulate the IGF-mediated effects in these cell lines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blotting, Western
  • Brain Neoplasms / metabolism*
  • Brain Neoplasms / pathology
  • Child
  • Child, Preschool
  • DNA Primers / chemistry
  • Female
  • Glioma / metabolism*
  • Glioma / pathology
  • Humans
  • Insulin-Like Growth Factor Binding Proteins / biosynthesis
  • Insulin-Like Growth Factor Binding Proteins / genetics*
  • Male
  • Middle Aged
  • Neoplasm Proteins / metabolism
  • RNA, Messenger / biosynthesis*
  • RNA, Neoplasm / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tumor Cells, Cultured


  • DNA Primers
  • Insulin-Like Growth Factor Binding Proteins
  • Neoplasm Proteins
  • RNA, Messenger
  • RNA, Neoplasm