Expression of hMSH2 and hMLH1 in colorectal carcinomas with microsatellite instability

Hoguen Kim, Zhe Piao, Jae Woo Kim, Jin Sub Choi, Nam Kyu Kim, Jae Myun Lee, Jeon Han Park

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

Microsatellite instability (MIN) due to defective mismatch repair (MMR) genes has been reported in a subset of sporadic colorectal carcinomas and in the majority of tumors from patients with hereditary nonpolyposis colorectal cancer (HNPCC) syndrome. Among the known MMR genes, hMSH2 and hMLH1 genes are known to be predominantly altered in HNPCC patients and MIN-positive tumors. In this study, we examined MIN and the protein expression pattern of the hMSH2 and hMLH1 by Western blot and immunohistochemistry from 32 sporadic colorectal carcinomas. MIN was observed in 6 (18%) colorectal carcinomas. Of the 6 MIN-positive tumors, one case showed no expression of either protein, 3 cases showed an absence of hMSH2 protein expression, one case showed an absence of hMLH1 protein expression and one case showed no altered expression of either protein by immunohistochemistry. The decreased expression of the hMSH2 protein in 3 tumor compared to the normal mucosa was also observed in 5 of the 6 MIN-positive cases by Western blot analysis. All of the MIN-negative tumors showed expression of both proteins by immunohistochemistry. Thus most of the MIN-positive tumors appear to be directely related to the altered expression of these two genes and can be diagnosed by the examination of protein expression.

Original languageEnglish
Pages (from-to)3-9
Number of pages7
JournalPathology Research and Practice
Volume194
Issue number1
DOIs
Publication statusPublished - 1998 Jan 1

All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine
  • Cell Biology

Fingerprint Dive into the research topics of 'Expression of hMSH2 and hMLH1 in colorectal carcinomas with microsatellite instability'. Together they form a unique fingerprint.

  • Cite this