Abstract
DNA hypermethylation of gene promoters is a common epigenetic alteration occurring in cancer cells. However, little is known about the mechanisms instructing these cancer-specific DNA hypermethylation events. Recent reports have suggested that genes bound by polycomb/Histone H3 lysine 27 trimethylation (H3K27me3) in embryonic stem (ES) cells are frequent targets for cancer-specific DNA hypermethylation. This polycomb-premarking is assumed to be restrained to ES cells, even though almost no polycomb/H3K27me3 binding profiles are available for differentiated tissues. We generated H3K27me3 profiles in human normal colon and they significantly overlapped with those of ES cells and genes hypermethylated in colorectal cancer (CRC). Moreover, colon H3K27me3 was more restricted to genes hypermethylated in CRC, while ES H3K27me3 was also common in genes hypermethylated in other tumors. Therefore, the suggested polycomb pre-marking of genes for cancer DNA hypermethylation is not necessarily limited to ES or early precursor cells but can occur later in differentiated tissues.
| Original language | English |
|---|---|
| Journal | Epigenetics : official journal of the DNA Methylation Society |
| Volume | 4 |
| Issue number | 2 |
| Pages (from-to) | 107-13 |
| Number of pages | 7 |
| Publication status | Published - 16 Feb 2009 |
| Externally published | Yes |
Keywords
- Adult
- Colon
- Colonic Neoplasms
- DNA Methylation
- Embryonic Stem Cells
- Histones
- Humans
- Lysine
- Methylation
- Polycomb-Group Proteins
- Repressor Proteins
