[Epigenetic alterations in myelodysplastic syndromes].

Epigenetic alterations are defined as heritable changes in gene expression mediated through mechanisms other than alterations in the DNA sequence itself, including DNA promoter methylation and various histone covalent modifications. Interacting of numerous epigenetic-associated molecules results in histone deacetylation/methylation and promoter methylation of suppressor genes, thereby transcription factors don't bind with promoters, leading to deactivation of tumor suppressor genes. It is widely accepted that epigenetic alterations play an important role in cancer development. It have known that many epigenetic alterations exist in myelodysplastic syndromes, for instance, promoter methylation of key control gene and aberrance of PcG, which probably have critical contribution to progression and prognosis of myelodysplastic syndromes. In future, it will be promising that epigenetic alterations serve as biomarkers for detection, evaluation of disease status and assessment of prognosis. Molecular basis of epigenetic alterations, inactivation of suppressor genes and abnormal expression of PcG in MDS are reviewed in this article.