It is now established that, as compared to normal cells, the cancer cell genome has an overall inverse distribution of DNA methylation ("methylome"), i.e., predominant hypomethylation and localized hypermethylation, within "CpG islands" (CGIs). Moreover, although cancer cells have reduced methylation "fidelity" and genomic instability, accurate maintenance of aberrant methylomes that underlie m...

BACKGROUND Majority of CpG dinucleotides in mammalian genomes tend to undergo DNA methylation, but most CpG islands are resistant to such epigenetic modification. Understanding about mechanisms that may lead to the methylation resistance of CpG islands is still very poor. METHODOLOGY/PRINCIPAL FINDINGS Using the genome-scale in vivo DNA methylation data from human brain, we investigated the f...

B-cell precursor acute lymphoblastic leukemia (pre-B ALL) is the most common pediatric cancer. Although the genetic determinants underlying disease onset remain unclear, epigenetic modifications including DNA methylation are suggested to contribute significantly to leukemogenesis. Using the Illumina 450K array, we assessed DNA methylation in matched tumor-normal samples of 46 childhood patients...

alteration in methylation pattern of promoters is associated with tumorigenic events,(1, 2) and differentiation control,(3, 4) in several types of cells in humans.specific hypermethylation in promoter region of some genes exist in different types of neoplastic cells.(5) dna methylation indicates to the addition of a methyl moiety to the cytosine in a cpg dinucleotide. cpg dinucleotides tend to ...

The methylation status of CpG islands is highly correlated with gene expression. Current methods for computational prediction of DNA methylation only utilize DNA sequence features. In this study, besides 35 DNA sequence features, we added four histone methylation marks to predict the methylation status of CpG islands, and improved the accuracy to 89.94%. Also we applied our model to predict the...

The p21 belongs to the CIP/KIP family of CDK inhibitors involved in cell cycle arrest at specific stages of the cell cycle progression. DNA methylation is the best studied epigenetic mark that have been evidently associated to chromatin condensation, and repression of gene transcription. The CpG island hypermethylation in promoter region of certain genes occurs in cancer cells and affects tumor...

A key open question in the understanding of the biology of DNA methylation relates to the origin and function of CpG islands, stretches of GC-rich and relatively CpG-rich DNA sequence that often colocalize with promoter regions. All housekeeping, but also a substantial minority of tissue-specific genes are associated with the CpG islands. Limited experimental evidence suggests that CpG islands ...

CpG islands mark CpG-enriched regions in otherwise CpG-depleted vertebrate genomes. While the regulatory importance of CpG islands is widely accepted, it is little appreciated that CpG islands vary greatly in lengths. For example, CpG islands in the human genome vary ∼30-fold in their lengths. Here we report findings suggesting that the lengths of CpG islands have functional consequences. Speci...