EPIGENETIC REGULATION

In normal cells, these modifications allow to modulate gene expression, and numerous factors are involved in these mechanisms (DNA methyltransferase, histone deacetylase and histone acetyltransferase, sirtuin, aurora kinase,...) ^(2,3). All these factors interact together to modulate gene expression, which notably lead to cell differenciation of totipotent cell ⁽³⁾.

In cancer, tumor cells modulate epigenetic factors to their advantage. These mechanisms lead to transcription activation of genes involved in signaling pathways, ordinary inactive (migration, invasion, cell proliferation, ...) ⁽⁵⁾. These activations are due to global DNA hypomethylation with a localised hypermethylation (tumor suppressor genes and cell cycle checkpoints). Histones are also modified in order to let the chromatin more accessible ⁽⁵⁾.
Epigenetic events are strongly involved in the cell carcinogenesis and cell invasion in new tissues by metastasis process ⁽⁶⁾