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Published on: September 20, 2018

Pharmacologic unmasking of epigenetically silenced genes in breast cancer

Kimberly Laskie Ostrow1, Hannah Lui Park, Mohammad Obaidul Hoque

  • 1Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins School of Medicine, Baltimore, MD 21231, USA.

Clinical Cancer Research : an Official Journal of the American Association for Cancer Research
|February 21, 2009
PubMed
Abstract

Insights

Researchers identified new cancer-specific methylated genes in breast cancer using a pharmacologic unmasking approach. These findings enhance understanding of breast cancer biology and offer potential diagnostic markers.

Area of Science:

  • Oncology
  • Epigenetics
  • Molecular Biology

Background:

  • Aberrant promoter hypermethylation is a frequent event in cancer pathogenesis, including breast cancer.
  • Numerous epigenetically silenced genes contributing to breast cancer remain unidentified.
  • Identifying novel epigenetically inactivated genes is crucial for understanding breast cancer development.

Purpose of the Study:

  • To identify epigenetically inactivated genes in breast cancer using a pharmacologic unmasking strategy.
  • To discover novel genes silenced by methylation in breast cancer.
  • To find potential diagnostic markers for breast cancer.

Main Methods:

  • Utilized a pharmacologic unmasking approach with 5-aza-2'-deoxycytidine (5-aza-dC) on breast cancer cell lines.
  • Employed microarray expression analysis to identify up-regulated genes post-treatment.
  • Confirmed cancer-specific methylation using bisulfite DNA sequencing and methylation-specific PCR techniques.

Main Results:

  • Microarray analysis revealed 49 genes up-regulated after 5-aza-dC treatment in breast cancer cell lines.
  • Five genes (MAL, FKBP4, VGF, OGDHL, KIF1A) exhibited cancer-specific methylation in breast tissues.
  • High-frequency methylation of at least two genes was observed exclusively in breast cancers (40/40) versus normal tissue (0/10).

Conclusions:

  • This study successfully identified novel cancer-specific methylated genes in breast cancer.
  • The findings contribute to elucidating the underlying biology of breast cancer.
  • Identified genes represent potential candidate diagnostic markers for breast cancer detection.

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