Somatic alterations of the DPC4 gene in human colorectal cancers in vivo

Gastroenterology. 1996 Nov;111(5):1369-72. doi: 10.1053/gast.1996.v111.pm8898652.

Abstract

Background & aims: The chromosome region 18q21 has been shown to be frequently deleted in colorectal cancers, and such frequent allelic loss is a hallmark of the presence of a tumor-suppressor gene. The DPC4 gene, which is located at 18q21, has been identified as a tumor-suppressor gene from examination of pancreatic cancers. The aim of the present study was to determine if it might also be altered in colorectal cancers.

Methods: Mutation analyses of the DPC4 gene were performed on complementary DNA samples from 31 primary colorectal cancer specimens using a combination of polymerase chain reaction, single-strand conformation polymorphism, and DNA sequencing.

Results: Four missense mutations producing amino acid substitutions and a somatic 12-base pair deletion in the coding region of the DPC4 gene were detected in the 31 cancers (16%; 5 of 31).

Conclusions: The DPC4 gene may play a role as a tumor-suppressor gene in a fraction of colorectal cancers; however, while allelic loss at 18q21 is very often seen in colorectal cancers, only a minority show DPC4 mutations, suggesting that there might be another tumor-suppressor gene in this chromosome region.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Colorectal Neoplasms / genetics*
  • DNA-Binding Proteins*
  • Female
  • Genes, Tumor Suppressor*
  • Humans
  • Male
  • Middle Aged
  • Mutation*
  • Smad4 Protein
  • Trans-Activators / genetics*

Substances

  • DNA-Binding Proteins
  • SMAD4 protein, human
  • Smad4 Protein
  • Trans-Activators