Project name: Homo sapiens

Description: In lung cancer, hypermethylation of specific gene promoters has been found during the progressive carcinogenesis. The identification of common methylation events will aid in the understanding of molecular events during neoplastic transformation and help develop biomarkers for cancer with high predictive and diagnostic value. To explore common methylation events on a genome-wide scale in lung cancer, we analyzed the methylation profiles of paired NSCLC tumor and far adjacent non-tumor samples using the HELP-microarray assay, which yields information on 1.2 million fragments throughout the genome. In this study, 24 pairs of tumor and adjacent non-tumor samples were analyzed using the HELP assay. At p = 5E-6, we identified 26,138 differentially methylated fragments (corresponding to 2 CpG sites each) in tumor versus non-tumor. The overall trend was consistent with genome-wide hypomethylation and locus specific hypermethylation (localized to CG-island containing promoters). We could identify both known and novel regions of the genome as well as specific gene-promoters that are hypermethylated in tumor versus non-tumor.The HELPassay: HpaII tiny fragment enrichment by ligation-mediated polymerase chain reaction [PCR] assayOverall design: 24 pairs of NSCLC subjects, tumor and paired non-tumor samples from each subject were analyzed. Individual HpaII restriction digest profiles were compared to an internal MspI digest control, to yield differentially methylated fragments for every sample. Samples were compared intra-subject between tumor and adjacent non-tumor for these differential methylation profiles and the overall significant changes across 24 subjects were identified.

Data type: Epigenomics

Sample scope: Multiisolate

Relevance: Medical

Release date: 2012-04-01

Last updated: 2012-02-03