Epigenomics of cancer – emerging new concepts

The complexity of the mammalian genome is regulated by heritable epigenetic mechanisms, which provide the basis for differentiation, development and cellular homeostasis. These mechanisms act on the level of chromatin, by modifying DNA, histone proteins and nucleosome density/composition. During the last decade it became clear that cancer is defined by a variety of epigenetic changes, which occur in early stages of disease and parallel genetic mutations. With the advent of new technologies we are just starting to unravel the cancer epigenome and latest mechanistic findings provide the first clue as to how altered epigenetic patterns might occur in different cancers. Here we review latest findings on chromatin related mechanisms and hypothesize how their impairment might contribute to the altered epigenome of cancer cells. ⺠Genome-wide analyses reveal epigenomic differences in functional regions. ⺠Epigenetic patterns occur in large domains in the genome. ⺠Epigenetic mechanisms are interrelated. ⺠Mutations of epigenetic enzymes are frequently associated with cancer. ⺠Changes in nuclear architecture are related to epigenomic alterations in cancer.