Genome-scale DNA methylation analysis in GI cancers

Abstract

Gastrointestinal cancer (GI Cancer) is the leading cause of cancer death in the world. Its prognosis is determined by clinical staging at diagnosis and treatment. Diagnostic tool such as gastrointestinal endoscopy followed by pathological analysis and/or fluoroscopy have proven useful; however, the mortality rate has remained high throughout the world. The need for less invasive and more efficient diagnostic tools has led to a search for GI cancer antigens. Molecular markers that distinguish benign from clinically silent malignant disease are needed to reduce the number of unnecessary endoscopic biopsies and to improve detection of GI cancer at an early stage. Cytosine DNA methylation is an important epigenetic change which leads to the recruitment of transcription repressors and chromatin changes. During the development and progression of GI cancer, many genes are silenced by aberrant methylation of CpG islands, which are CpG dinucleotide-rich areas located within the promoters of approximately 60% of human genes. Recently, methylated CpG island amplification microarray (MCAM) based genome-wide DNA methylation profiles have been available for analyzing primary neoplasms. We reported that DNA methylation analysis using MCAM is useful for the detection of primary GI cancers.