Cancer Epigenetics

Definition

Epigenetics is defined as chromatin modifications that can alter gene expression, are heritable during cell division, but do not involve a change in DNA coding sequence.

Characteristics

In the context of normal biological processes, epigenetic mechanisms establish regions within the genome containing transcriptionally active (termed euchromatin) and silent (termed heterochromatin) DNA. Further, epigenetic mechanisms are responsible for stably inherited patterns of gene expression such as X chromosome inactivation and genomic imprinting (i.e., selective expression of maternal or paternal alleles). Chromatin modifications that alter gene expression are both changes to the methylation state of DNA and posttranslational modifications to histone complexes.

It is well recognized that genetic mutations occur in cancer cells and that these events can exert profound and disease-associated changes in gene expression and/or function. However, it is becoming widely accepted that cancer...