Epigenetics and Human DiseasesConference

Epigenetic of Cancer

Global DNA hypomethylation and gene-specific hypermethylation have been observed in human cancer cells obtained from clinical tissue biopsies. During initial studies of cancer epigenetics, the genome of patients with colorectal cancer was reported to be hypomethylated. In these patients, regions that are hypermethylated under normal conditions and silent regions of the genome were found to be demethylated. In some malignancies, however, abnormal gene activity, such as inhibition of tumor-suppressor genes, has been linked to hypermethylation of CpG islands. By hypermethylating DNA, repeating DNA sequences such as microsatellites become functionally abnormal and cause tumorigenesis. microsatellites in colorectal and ovarian cancers are distorted by abnormal epigenetic modulations in the MLH1 promoter (a DNA repair gene).

Cancer epigenetics is the study of epigenetic modifications to the DNA of cancer cells that do not involve a change in the nucleotide sequence, but instead involve a change in the way the genetic code is expressed.