Up-regulation of DNA methyltransferase 3B expression in endometrial cancers

Fan Jin, Sean C. Dowdy, Yuning Xiong, Norman L. Eberhardt, Karl C. Podratz, Shi Wen Jiang

Research output: Contribution to journalArticle

56 Scopus citations

Abstract

To understand the role of epigenetic regulation in the pathogenesis of endometrial cancer, we have characterized DNA methyltransferase 3B (DNMT3B) gene expression in normal, Grade I and Grade III endometrioid cancers, and examined DNMT3B promoter activities in endometrial cancer cell lines. DNMT3B expression was measured in normal, Grade I, and Grade III endometrioid cancer samples. Real-time PCR and Western blot analysis were performed to compare DNMT3B mRNA and protein levels. DNMT3B levels were also compared among endometrial cell lines including those for Ishikawa, KLE, AN3, RL-95, HEC-1A, and HEC-1B. DNMT3B promoter reporter plasmids were constructed. Promoter activities in well and poorly differentiated cell lines were compared by in vitro reporter gene transfection. DNMT3B was significantly up-regulated in both Grade I and Grade III cancers as compared to normal controls. Western blot analysis confirmed the increased DNMT3B protein expression in cancer tissues. It was also found that the well-differentiated endometrial cell line, Ishikawa, expressed lower levels of DNMT3B than the poorly differentiated KLE cells, the expression patterns similar to those observed in tumor specimens. The results suggest that DNMT3B overexpression may play a significant role in endometrial cancer development. In addition, the transfection experiments indicated that DNMT3B promoters are more active in the poorly differentiated endometrial cancer cell lines, suggesting that the in vitro assay provides a useful model for studying the DNMT3B transactivation mechanism related to tumor transformation.

Original languageEnglish (US)
Pages (from-to)531-538
Number of pages8
JournalGynecologic oncology
Volume96
Issue number2
DOIs
StatePublished - Feb 1 2005

Keywords

  • DNA methyltransferase
  • Endometrial cancer
  • Gene expression
  • Transcription

ASJC Scopus subject areas

  • Oncology
  • Obstetrics and Gynecology

Fingerprint Dive into the research topics of 'Up-regulation of DNA methyltransferase 3B expression in endometrial cancers'. Together they form a unique fingerprint.

  • Cite this