Newsletter50

-Arraystar 4*180K Cancer DMR Microarray

Small DMRs refer to the cancer-specific differentially methylated genomic regions smaller than 5 kb. More than 10,000 cancer-specific small DMRs have been identified in various human tumors [1]. The small DMRs are involved in the loss of stability of DNA methylation in cancer, which can be classified in three types: (1) Shifting of methylation boundaries into or out of the CpG islands causing either hyper- or hypo-methylation (Fig. 2a,b); (2) Loss of? normal methylation boundaries forming hypermethylated islands (Fig. 2c); and (3) Novel hypomethylation that arose de novo in highly methylated regions (Fig.2d). The strongest relationship between gene expression and methylation has been observed for hypomethylated shores due to methylation boundary shifts.

Arraystar 4 x 180K Cancer DMR Microarray is specifically designed to study the DMRs in human cancers. This microarray is new and powerful cancer epigenetics tool to analyze:

• Methylation changes
• Histone modifications
• Transcription factor binding
• Both protein-coding and long non-coding RNA genes regulated in the DMRs.

By combining gene expression profiling data from Arraystar gene expression microarrays, the dynamics of methylation and gene expression in cancers can be integrated and the biology analyzed.

Figure 2. Classification of DMRs (shaded pink) in cancer: a methylation boundary shift outward (a) or inward (b), a loss of methylation boundary (c), and a de novo hypomethylation (d). Grey bars indicate the location of hypomethylation blocks, CpG islands, and gene exons. Tick marks along the bottom axis indicate the location of CpG sites [1].

References
1. Hansen, K. D., et al. (2011) Nat Genet 43 (8): 768-75