A series of amidopropenyl hydroxamic acid derivatives were prepared as novel inhibitors of human histone deacetylases (HDACs). Several compounds showed potency at <100 nM in the HDAC inhibition assays, sub-micromolar IC(50) values in tests against three tumor cell lines, and remarkable stability in human and mouse microsomes was observed. Three representative compounds were selected for further characterization and submitted to a selectivity profile against a series of class I and class II HDACs as well as to preliminary in vivo pharmacokinetic (PK) experiments.
View Article and Find Full Text PDFThe position of genes in the interphase nucleus and their association with functional landmarks correlate with active and/or silent states of expression. Gene activation can induce chromatin looping from chromosome territories (CTs) and is thought to require de novo association with transcription factories. We identify two types of factory: "poised transcription factories," containing RNA polymerase II phosphorylated on Ser5, but not Ser2, residues, which differ from "active factories" associated with phosphorylation on both residues.
View Article and Find Full Text PDFThe histone deacetylases (HDACs) are able to regulate gene expression, and histone deacetylase inhibitors (HDACi) emerged as a new class of agents in the treatment of cancer as well as other human disorders such as neurodegenerative diseases. In the present investigation, we report on the synthesis and biological evaluation of compounds derived from the expansion of a HDAC inhibitor scaffold having N-hydroxy-3-phenyl-2-propenamide and N-hydroxy-3-(pyridin-2-yl)-2-propenamide as core structures and containing a phenyloxopropenyl moiety, either unsubstituted or substituted by a 4-methylpiperazin-1-yl or 4-methylpiperazin-1-ylmethyl group. The compounds were evaluated for their ability to inhibit nuclear HDACs, as well as for their in vitro antiproliferative activity.
View Article and Find Full Text PDFWe show the interaction between the enhancer and the minimal promoter of urokinase-type plasminogen activator gene during active transcription by coupling micrococcal nuclease digestion of cross-linked, sonicated chromatin, and chromatin immunoprecipitation. This approach allowed the precise identification of the interacting genomic fragments, one of which is resistant to micrococcal nuclease cleavage. The interacting fragments form a single transcriptional control unit, as indicated by their common protein content.
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