Quantitative Evaluation of NOD2 Promoter Methylation Profiling in Colon Biopsy Samples from Ulcerative Colitis Patients and Non-Colitis Controls

Ulcerative colitis (UC) is an idiopathic chronic inflammatory disease of the colon with evidence addressing the role of epigenetic changes. The intention of this study was to detect the association of DNA methylation levels of NOD2 gene with UC and to evaluate whether any of these changes might be a useful biomarker for detecting patients with UC.

The methylation status of the promoter CpG islands (CGIs) of NOD2 gene was examined in the colonic mucosae of 15 cancer-free patients with UC and 15 age- and sex-matched healthy controls by the real-time quantitative multiplex-methylation specific PCR (QM-MSP) assay. Methylation-specific melting curve analysis (MS-MCA) was used to analyze the data.

The median unmethylated DNA index was significantly higher in cases compared to controls, and hypormethylation of NOD2 gene was significantly correlated with UC (Unmethylated DNA in UC vs. HC; 0.102±0.055 vs. 0.025±0.016, P = 0.000).

The NOD2 gene that was differentially methylated in UC patients, provides new insights into the pathogenesis of UC, with a view to making steps toward the development of accurate biomarkers for diagnostic tools in UC.