Related Experiment Video
Updated: Aug 18, 2026

Enhanced Reduced Representation Bisulfite Sequencing for Assessment of DNA Methylation at Base Pair Resolution
Published on: February 24, 2015
Alteration of DNA methylation in gastrointestinal carcinogenesis
1Shanghai Institute of Digestive Disease, Shanghai Second Medical University, Shanghai, People's Republic of China. jyfang@public9.sta.net.cn
Abstract:
DNA methylation is the main epigenetic modification in humans. The methylation of promoter inhibits the transcription in most genes. In normal tissues, isolated CpG dinucleotides in bulk chromatin are often methylated, whereas cytosines in CpG islands are unmethylated. In neoplasms including gastrointestinal cancer, this pattern of methylation is commonly reversed. The alteration of DNA methylation plays a key role in the process of carcinogenesis. The gastrointestinal carcinogenesis is suggested to be associated with the decrease of total genomic DNA methylation; hypomethylation of certain specific oncogenes such as c-myc, c-Ha-ras, c-fos and alpha-fetoprotein; and hypermethylation of the promoter of some tumor suppressor genes containing p16(INK4A), E-cadherin and hMLH1 genes. This review focuses on the analysis methods for methylation, studies for aberrant DNA methylation in gastrointestinal carcinogenesis, and the intervention changing methylation, including the treatment of 5-azacytidine, supplement of folate and gene therapy.
Related Concept Videos
Epigenetic Regulation
Genomic Imprinting and Inheritance
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...
Epigenetic Regulation
X-chromosome...
Mutagenicity and Carcinogenicity
Phase II Reactions: Methylation Reactions
The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...
Spontaneous and Induced Mutations

