Epigenetics and blood disorders.

The last three decades of cancer research were guided by the hypothesis that cancer cells evolve due to the accumulation of many genetic aberrations over time. While this is still true for most solid cancers, it might be different in haemato-malignant diseases, which are mostly characterized by chromosomal translocations that exhibit only few additional mutations. Some of the resulting fusion gene products functionally interfer with epigenetic mechanisms. Recent findings of mutated IDH1, IDH2, DNMT3A or TET2 in myelodysplastic syndrome/acute myeloid leukaemia patients underscore this notion, and point to the importance of epigenetic changes for developing tumour cells. This review aims (i) to give an overview about the different components of the epigenetic system, (ii) to describe the functions of different proteins or complexes that are involved in setting-up the epigenetic layer, (iii) to highlight some recent findings, and (iv) to describe the failures and successes when using drugs that are targeting epigenetic components.