Abnormal expression and structural modification of the insulin-like growth-factor-II gene in human colorectal tumors

Int J Cancer. 1990 Sep 15;46(3):405-10. doi: 10.1002/ijc.2910460313.

Abstract

The insulin-like growth factor II (IGF-II) is a small protein implicated in fetal growth and development. It may play a role in the neoplastic process. The IGF-II gene is located on the short arm of chromosome II near insulin and c-Ha-ras I genes. Three distinct promoters control the transcription of this gene, leading to different IGF-II mRNA species. We have analyzed 21 human colorectal tumors and found overexpression of IGF-II in 6 of them (30%). When compared with expression in normal adjacent tissues, IGF-II mRNA increase in these tumors was either moderate (2- to 15-fold) or very marked (200- to 800-fold). In situ hybridization experiments confirmed that high IGF-II mRNA amounts were localized in cancer cells of the tumors overexpressing the IGF-II gene. In addition, DNA analysis revealed a structural modification of one IGF-II locus in one tumor characterized by very high IGF-II mRNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics*
  • Adenocarcinoma / metabolism
  • Aged
  • Autoradiography
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / metabolism
  • Female
  • Gene Expression*
  • Humans
  • Immunoblotting
  • Insulin-Like Growth Factor II / genetics*
  • Insulin-Like Growth Factor II / metabolism
  • Intestinal Mucosa / metabolism
  • Male
  • Middle Aged
  • Molecular Probe Techniques
  • Polymorphism, Restriction Fragment Length
  • RNA, Messenger / metabolism
  • Restriction Mapping
  • Somatomedins / genetics*

Substances

  • RNA, Messenger
  • Somatomedins
  • Insulin-Like Growth Factor II