RT Journal A1 Estécio, Marcos R.H. A1 Yan, Pearlly S. A1 Ibrahim, Ashraf E.K. A1 Tellez, Carmen S. A1 Shen, Lanlan A1 Huang, Tim H.-M. A1 Issa, Jean-Pierre J. T1 High-throughput methylation profiling by MCA coupled to CpG island microarray JF Genome Research JO Genome Research YR 2007 FD October 01 VO 17 IS 10 SP 000 OP 000 DO 10.1101/gr.6417007 UL http://genome.cshlp.org/content/early/2007/09/04/gr.6417007.abstract AB An abnormal pattern of DNA methylation occurs at specific genes in almost all neoplasms. The lack of high-throughput methods with high specificity and sensitivity to detect changes in DNA methylation has limited its application for clinical profiling. Here we overcome this limitation and present an improved method to identify methylated genes genome-wide by hybridizing a CpG island microarray with amplicons obtained by the methylated CpG island amplification technique (MCAM). We validated this method in three cancer cell lines and 15 primary colorectal tumors, resulting in the discovery of hundreds of new methylated genes in cancer. The sensitivity and specificity of the method to detect hypermethylated loci were 88% and 96%, respectively, according to validation by bisulfite-PCR. Unsupervised hierarchical clustering segregated the tumors into the expected subgroups based on CpG island methylator phenotype classification. In summary, MCAM is a suitable technique to discover methylated genes and to profile methylation changes in clinical samples in a high-throughput fashion.