Epigenomic repression by APL oncoprotein

摘要

In acute promyelocytic leukemia (APL), a t(15;17) translocation leads to the production of PML-RARa, the fusion oncoprotein responsible for the vast majority of APL cases. Expression of PML-RARa leads to transcriptional repression of RARa target genes and a differentiation block at the promyelocytic stage, but also to a unique responsiveness to treatment with all-trans retinoic acid (ATRA).In this issue of Blood, Hoemme and colleagues present a comprehensive study using chromatin precipitation (ChIP)-chip as well as microarrays to analyze changes that occur with induced expression of PML-RARa in a promonocytic cell line. The authors used different antibodies to correlate PML-RARa binding to gene promoters with epigenetic modifications, including histone acetylation and methylation