Heterogeneous DNA Methylation Patterns in the GSTP1 Promoter Lead to Discordant Results between Assay Technologies and Impede Its Implementation as Epigenetic Biomarkers in Breast Cancer

Genes

Grethe I. Grenaker Alnaes³  Jo Anders Ronneberg³  Vessela N. Kristensen³  Jörg Tost²  Jeffrey Craig¹ 

[1] Department of Cancer genetics, Institute for Cancer Research, Oslo University Hospital, Radiumhospitalet, Oslo 0310, Norway;;Laboratory for Epigenetics and Environment, Centre National de Génotypage, CEA-Institut de Génomique, Evry 91000, France;Department of Cancer genetics, Institute for Cancer Research, Oslo University Hospital, Radiumhospitalet, Oslo 0310, Norway; E-Mails:

关键词: DNA methylation;    breast cancer;    GSTP1;    biomarker;    heterogeneity;    method;    MethyLight;    MSP;    pyrosequencing;    mass spectrometry;   

DOI  :  10.3390/genes6030878

来源: mdpi

【 摘 要 】

Altered DNA methylation patterns are found in many diseases, particularly in cancer, where the analysis of DNA methylation holds the promise to provide diagnostic, prognostic and predictive information of great clinical value. Methylation of the promoter-associated CpG island of GSTP1 occurs in many hormone-sensitive cancers, has been shown to be a biomarker for the early detection of cancerous lesions and has been associated with important clinical parameters, such as survival and response to treatment. In the current manuscript, we assessed the performance of several widely-used sodium bisulfite conversion-dependent methods (methylation-specific PCR, MethyLight, pyrosequencing and MALDI mass-spectrometry) for the analysis of DNA methylation patterns in the GSTP1 promoter. We observed large discordances between the results obtained by the different technologies. Cloning and sequencing of the investigated region resolved single-molecule DNA methylation patterns and identified heterogeneous DNA methylation patterns as the underlying cause of the differences. Heterogeneous DNA methylation patterns in the GSTP1 promoter constitute a major obstacle to the implementation of DNA methylation-based analysis of GSTP1 and might explain some of the contradictory findings in the analysis of the significance of GSTP1 promoter methylation in breast cancer.

【 授权许可】

CC BY   
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