Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Molecular subtypes of breast cancer are associated with characteristic DNA methylation patterns

Author:
  • Karolina Holm
  • Cecilia Hegardt
  • Johan Staaf
  • Johan Vallon-Christersson
  • Göran B Jönsson
  • Håkan Olsson
  • Åke Borg
  • Markus Ringnér
Publishing year: 2010
Language: English
Publication/Series: Breast Cancer Research
Volume: 12
Issue: 3
Document type: Journal article
Publisher: BioMed Central

Abstract english

Introduction: Five different molecular subtypes of breast cancer have been identified through gene expression profiling. Each subtype has a characteristic expression pattern suggested to partly depend on cellular origin. We aimed to investigate whether the molecular subtypes also display distinct methylation profiles. Methods: We analysed methylation status of 807 cancer-related genes in 189 fresh frozen primary breast tumours and four normal breast tissue samples using an array-based methylation assay. Results: Unsupervised analysis revealed three groups of breast cancer with characteristic methylation patterns. The three groups were associated with the luminal A, luminal B and basal-like molecular subtypes of breast cancer, respectively, whereas cancers of the HER2-enriched and normal-like subtypes were distributed among the three groups. The methylation frequencies were significantly different between subtypes, with luminal B and basal-like tumours being most and least frequently methylated, respectively. Moreover, targets of the polycomb repressor complex in breast cancer and embryonic stem cells were more methylated in luminal B tumours than in other tumours. BRCA2-mutated tumours had a particularly high degree of methylation. Finally, by utilizing gene expression data, we observed that a large fraction of genes reported as having subtype-specific expression patterns might be regulated through methylation. Conclusions: We have found that breast cancers of the basal-like, luminal A and luminal B molecular subtypes harbour specific methylation profiles. Our results suggest that methylation may play an important role in the development of breast cancers.

Keywords

  • Cancer and Oncology

Other

Published
  • CREATE Health
  • ISSN: 1465-5411
Åke Borg
Åke Borg
E-mail: ake [dot] borg [at] med [dot] lu [dot] se

Principal investigator

Oncology and Pathology, MV

+46 46 275 25 52

MV 404 C21B2

90

Project manager

Familial Breast Cancer

90

Professor

Oncology and Pathology, MV

MV 404 C21C2

90