Loss of heterozygosity status of D9S105 marker is associated with downregulation of Krüppel-like factor 4 expression in pancreatic ductal adenocarcinoma and pancreatic intraepithelial lesions

Pancreatology. 2011;11(1):30-42. doi: 10.1159/000322990. Epub 2011 Mar 16.

Abstract

The transcription factor Krüppel-like factor 4 (KLF4) may act both as an oncogene and a tumor suppressor in a tissue-dependent manner, and further studies on its role in pancreatic ductal adenocarcinoma (PDAC) progression and clinical outcome are warranted. Therefore, we investigated the loss of heterozygosity (LOH) in the 9q22.3-32 region and loss of KFL4 gene expression in epithelial cells from 35 PDAC, 6 pancreatic intraductal neoplasias (PanINs) and 6 normal ducts, isolated by laser microdissection, as well as their correlation with overall survival (OS) in patients treated with gemcitabine in the adjuvant setting. LOH was evaluated with 4 microsatellite markers and in situ hybridization, while KLF4 expression was studied by reverse transcription-PCR and immunohistochemistry. LOH in at least 1 locus was observed in 25 of 35 PDAC cases and in 5 of 6 PanINs, respectively. In particular, the loss of the D9S105 marker was present in 46.9% of PDAC and 83.3% of PanINs, becoming the most deleted marker, while no LOH in D9S105 was observed in normal Wirsung pancreatic duct. Lack of KLF4 mRNA expression was significantly associated with: (1) genomic deletion flanking KLF4 in PDAC and in PanINs (with LOH of D9S105), (2) low-grade PDAC-associated PanIN, (3) lack of KLF4 protein expression, and (4) shorter OS. These results strongly suggest a relationship between D9S105 deletion and downregulation of KLF4 gene expression as an early event in PDAC progression, as well as a possible role of KLF4 as a prognostic biomarker in gemcitabine-treated patients. and IAP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / metabolism
  • Carcinoma in Situ / genetics*
  • Carcinoma in Situ / metabolism
  • Carcinoma in Situ / pathology
  • Carcinoma, Pancreatic Ductal / genetics*
  • Carcinoma, Pancreatic Ductal / metabolism
  • Carcinoma, Pancreatic Ductal / pathology
  • Down-Regulation*
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors / genetics*
  • Kruppel-Like Transcription Factors / metabolism
  • Loss of Heterozygosity*
  • Male
  • Microsatellite Repeats
  • Middle Aged
  • Pancreatic Neoplasms / genetics*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • RNA, Messenger / metabolism
  • Retrospective Studies
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Biomarkers, Tumor
  • KLF4 protein, human
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors
  • RNA, Messenger