DNA hypomethylation affects cancer-related biological functions and genes relevant in neuroblastoma pathogenesis

PLoS One. 2012;7(11):e48401. doi: 10.1371/journal.pone.0048401. Epub 2012 Nov 7.

Abstract

Neuroblastoma (NB) pathogenesis has been reported to be closely associated with numerous genetic alterations. However, underlying DNA methylation patterns have not been extensively studied in this developmental malignancy. Here, we generated microarray-based DNA methylation profiles of primary neuroblastic tumors. Stringent supervised differential methylation analyses allowed us to identify epigenetic changes characteristic for NB tumors as well as for clinical and biological subtypes of NB. We observed that gene-specific loss of DNA methylation is more prevalent than promoter hypermethylation. Remarkably, such hypomethylation affected cancer-related biological functions and genes relevant to NB pathogenesis such as CCND1, SPRR3, BTC, EGF and FGF6. In particular, differential methylation in CCND1 affected mostly an evolutionary conserved functionally relevant 3' untranslated region, suggesting that hypomethylation outside promoter regions may play a role in NB pathogenesis. Hypermethylation targeted genes involved in cell development and proliferation such as RASSF1A, POU2F2 or HOXD3, among others. The results derived from this study provide new candidate epigenetic biomarkers associated with NB as well as insights into the molecular pathogenesis of this tumor, which involves a marked gene-specific hypomethylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child
  • Child, Preschool
  • Cyclin D1 / genetics
  • Cyclin D1 / metabolism
  • DNA Methylation / genetics*
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic
  • Genes, Neoplasm / genetics*
  • Humans
  • Infant
  • Infant, Newborn
  • Neuroblastoma / genetics*
  • Reproducibility of Results
  • Sequence Analysis, DNA
  • Temperature

Substances

  • CCND1 protein, human
  • Cyclin D1

Grants and funding

This work was supported by grants from the Spanish Ministry of Health (Instituto de Salud Carlos III, Fondo de Investigación Sanitaria, 2007; PI070286) and Spanish Society against Cancer (Asociación Española Contra el Cáncer, 2007). G.M. is supported by a grant of Hospital Sant Joan de Déu of Barcelona (Grant BR201102), S.G. by a donation from the NEN association and J.I.M-S. studies on epigenomics are supported by the Spanish Ministry of Science and Innovation (RyC contract and SAF2009-08663).