Analysis of epigenetic changes in human colorectal cancer and matching mucosa tissues

We used NimbleGen human CpG/promoter microarrays for profiling epigenetic changes (DNA methylation, H3K27me3 and H3K4me3 marks) in colon tumors (Duke's stage II) and matching mucosa samples from patients. Analysis of DNA methylation was done by using the methylated CpG island recovery assay (MIRA) technique with further hybridization versus input on NimbleGen human CpG/promoter microarrays. For profiling of H3K27me3 and H3K4me3 marks, we performed chromatin immunoprecipitation with H3K27me3 (#07-449, Millipore) and H3K4me3 (#39159, Active Motif) antibodies and further hybridized versus input on NimbleGen human CpG/promoter microarrays. All experiments were performed simultaneously for matching tissue samples.