Genome-wide DNA Methylation Profiling of Cell-Free Serum DNA in Esophageal Adenocarcinoma and Barrett Esophagus 1 2

Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA.
Neoplasia (New York, N.Y.) (Impact Factor: 4.25). 01/2012; 14(1):29-33. DOI: 10.1593/neo.111626
Source: PubMed

ABSTRACT Aberrant DNA methylation (DNAm) is a feature of most types of cancers. Genome-wide DNAm profiling has been performed successfully on tumor tissue DNA samples. However, the invasive procedure limits the utility of tumor tissue for epidemiological studies. While recent data indicate that cell-free circulating DNAm (cfDNAm) profiles reflect DNAm status in corresponding tumor tissues, no studies have examined the association of cfDNAm with cancer or precursors on a genome-wide scale. The objective of this pilot study was to evaluate the putative significance of genome-wide cfDNAm profiles in esophageal adenocarcinoma (EA) and Barrett esophagus (BE, EA precursor). We performed genome-wide DNAm profiling in EA tissue DNA (n = 8) and matched serum DNA (n = 8), in serum DNA of BE (n = 10), and in healthy controls (n = 10) using the Infinium HumanMethylation27 BeadChip that covers 27,578 CpG loci in 14,495 genes. We found that cfDNAm profiles were highly correlated to DNAm profiles in matched tumor tissue DNA (r = 0.92) in patients with EA. We selected the most differentially methylated loci to perform hierarchical clustering analysis. We found that 911 loci can discriminate perfectly between EA and control samples, 554 loci can separate EA from BE samples, and 46 loci can distinguish BE from control samples. These results suggest that genome-wide cfDNAm profiles are highly consistent with DNAm profiles detected in corresponding tumor tissues. Differential cfDNAm profiling may be a useful approach for the noninvasive screening of EA and EA premalignant lesions.

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    • "This highlights the possibility of using these changes as a marker for the prognosis and diagnosis of those diseases. Indeed, the methylation patterns of the cfDNA in serum have been recently used for the diagnosis of different types of tumors [4] [5] as well as in other non-oncogenic diseases [6]. "
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