|Cancer cells splitting. (stock image)|
This study looked at six different types of cancers: breast, colon, lung, two different pancreal cancers, and thyroid. Using microarray analysis, the researchers analyzed the methylation patterns of the DNA isolated from the cancer cells. They found that, compared to normal cells, the tumor cells had completely different methylation patterns. Some large blocks of DNA in the tumor cells were demethylated while smaller sections had lots of methylation. All of the cancer types had these large demethylated sections, with some types having smaller regions within these blocks that were highly methylated. These epigenetic modifications occur at the earliest stages of tumor development.
|DNA methylation in chromosome 5. Normal cells are shown in the top|
panel, cancer cells in the bottom panel.
But it's not all bad news, the researchers are confident that this new information on cancer epigenetics could provide a foundation for the development of early screening and diagnosis. Epigenetic screens could be used to distinguish cancer cells from benign growths.