Newsletter49

- Arraystar 4*180K Human Block Microarray

Hypomethylated blocks are 5 kb ~ 10 Mbp continuous blocks of genomic regions that are hypomethylated and account for up to 95% of the methylation changes in cancer. They have been recently discovered as a universal defining epigenetic alteration in tumors [1,2]. About 1/3 of the single copy gene transcription start sites (TSS) are covered by the blocks. In cancer samples, the blocks are hypervariable in methylation, so are the genes in the blocks expressed at higher or extreme variability (Fig. 1). The methylation and expression hypervariability is just as or perhaps even more important features in cancer heterogeneity, progression and epigenetic destabilization.

Arraystar 4 x 180K Human Block Microarray is specifically designed to study the blocks in human cancers. This microarray is a 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 blocks.

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 1. The expression values for 26 hypervariable genes in cancer located within hypomethylated blocks, with cancer samples (red) showing large expressional variations compared to the normal samples (blue) [1].

References
1. Hansen, K. D., et al. (2011) Nat Genet 43 (8): 768-75.
2. Timp, W., et al. (2014) Genome Med 6 (8): 61.