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1

Histone deacetylases (HDACs): characterization of the classical HDAC family.  

PubMed Central

Transcriptional regulation in eukaryotes occurs within a chromatin setting, and is strongly influenced by the post-translational modification of histones, the building blocks of chromatin, such as methylation, phosphorylation and acetylation. Acetylation is probably the best understood of these modifications: hyperacetylation leads to an increase in the expression of particular genes, and hypoacetylation has the opposite effect. Many studies have identified several large, multisubunit enzyme complexes that are responsible for the targeted deacetylation of histones. The aim of this review is to give a comprehensive overview of the structure, function and tissue distribution of members of the classical histone deacetylase (HDAC) family, in order to gain insight into the regulation of gene expression through HDAC activity. SAGE (serial analysis of gene expression) data show that HDACs are generally expressed in almost all tissues investigated. Surprisingly, no major differences were observed between the expression pattern in normal and malignant tissues. However, significant variation in HDAC expression was observed within tissue types. HDAC inhibitors have been shown to induce specific changes in gene expression and to influence a variety of other processes, including growth arrest, differentiation, cytotoxicity and induction of apoptosis. This challenging field has generated many fascinating results which will ultimately lead to a better understanding of the mechanism of gene transcription as a whole. PMID:12429021

de Ruijter, Annemieke J M; van Gennip, Albert H; Caron, Huib N; Kemp, Stephan; van Kuilenburg, Andre B P

2003-01-01

2

Histone deacetylases (HDACs) in XPC gene silencing and bladder cancer  

PubMed Central

Bladder cancer is one of the most common malignancies and causes hundreds of thousands of deaths worldwide each year. Bladder cancer is strongly associated with exposure to environmental carcinogens. It is believed that DNA damage generated by environmental carcinogens and their metabolites causes development of bladder cancer. Nucleotide excision repair (NER) is the major DNA repair pathway for repairing bulk DNA damage generated by most environmental carcinogens, and XPC is a DNA damage recognition protein required for initiation of the NER process. Recent studies demonstrate reduced levels of XPC protein in tumors for a majority of bladder cancer patients. In this work we investigated the role of histone deacetylases (HDACs) in XPC gene silencing and bladder cancer development. The results of our HDAC inhibition study revealed that the treatment of HTB4 and HTB9 bladder cancer cells with the HDAC inhibitor valproic acid (VPA) caused an increase in transcription of the XPC gene in these cells. The results of our chromatin immunoprecipitation (ChIP) studies indicated that the VPA treatment caused increased binding of both CREB1 and Sp1 transcription factors at the promoter region of the XPC gene for both HTB4 and HTB9 cells. The results of our immunohistochemistry (IHC) staining studies further revealed a strong correlation between the over-expression of HDAC4 and increased bladder cancer occurrence (p < 0.001) as well as a marginal significance of increasing incidence of HDAC4 positivity seen with an increase in severity of bladder cancer (p = 0.08). In addition, the results of our caspase 3 activation studies demonstrated that prior treatment with VPA increased the anticancer drug cisplatin-induced activation of caspase 3 in both HTB4 and HTB9 cells. All of these results suggest that the HDACs negatively regulate transcription of the XPC gene in bladder cancer cells and contribute to the severity of bladder tumors. PMID:21507255

2011-01-01

3

Hydroxamic Acid-Based Histone Deacetylase (HDAC) Inhibitors Can Mediate Neuroprotection Independent of HDAC Inhibition.  

PubMed

Histone deacetylase (HDAC) inhibition improves function and extends survival in rodent models of a host of neurological conditions, including stroke, and neurodegenerative diseases. Our understanding, however, of the contribution of individual HDAC isoforms to neuronal death is limited. In this study, we used selective chemical probes to assess the individual roles of the Class I HDAC isoforms in protecting Mus musculus primary cortical neurons from oxidative death. We demonstrated that the selective HDAC8 inhibitor PCI-34051 is a potent neuroprotective agent; and by taking advantage of both pharmacological and genetic tools, we established that HDAC8 is not critically involved in PCI-34051's mechanism of action. We used BRD3811, an inactive ortholog of PCI-34051, and showed that, despite its inability to inhibit HDAC8, it exhibits robust neuroprotective properties. Furthermore, molecular deletion of HDAC8 proved insufficient to protect neurons from oxidative death, whereas both PCI-34051 and BRD3811 were able to protect neurons derived from HDAC8 knock-out mice. Finally, we designed and synthesized two new, orthogonal negative control compounds, BRD9715 and BRD8461, which lack the hydroxamic acid motif and showed that they stably penetrate cell membranes but are not neuroprotective. These results indicate that the protective effects of these hydroxamic acid-containing small molecules are likely unrelated to direct epigenetic regulation via HDAC inhibition, but rather due to their ability to bind metals. Our results suggest that hydroxamic acid-based HDAC inhibitors may mediate neuroprotection via HDAC-independent mechanisms and affirm the need for careful structure-activity relationship studies when using pharmacological approaches. PMID:25339746

Sleiman, Sama F; Olson, David E; Bourassa, Megan W; Karuppagounder, Saravanan S; Zhang, Yan-Ling; Gale, Jennifer; Wagner, Florence F; Basso, Manuela; Coppola, Giovanni; Pinto, John T; Holson, Edward B; Ratan, Rajiv R

2014-10-22

4

The Role of Dietary Histone Deacetylases (HDACs) Inhibitors in Health and Disease  

PubMed Central

Modification of the histone proteins associated with DNA is an important process in the epigenetic regulation of DNA structure and function. There are several known modifications to histones, including methylation, acetylation, and phosphorylation, and a range of factors influence each of these. Histone deacetylases (HDACs) remove the acetyl group from lysine residues within a range of proteins, including transcription factors and histones. Whilst this means that their influence on cellular processes is more complex and far-reaching than histone modifications alone, their predominant function appears to relate to histones; through deacetylation of lysine residues they can influence expression of genes encoded by DNA linked to the histone molecule. HDAC inhibitors in turn regulate the activity of HDACs, and have been widely used as therapeutics in psychiatry and neurology, in which a number of adverse outcomes are associated with aberrant HDAC function. More recently, dietary HDAC inhibitors have been shown to have a regulatory effect similar to that of pharmacological HDAC inhibitors without the possible side-effects. Here, we discuss a number of dietary HDAC inhibitors, and how they may have therapeutic potential in the context of a whole food. PMID:25322459

Bassett, Shalome A.; Barnett, Matthew P. G.

2014-01-01

5

CD4(+) T cell lineage integrity is controlled by the histone deacetylases HDAC1 and HDAC2.  

PubMed

Molecular mechanisms that maintain lineage integrity of helper T cells are largely unknown. Here we show histone deacetylases 1 and 2 (HDAC1 and HDAC2) as crucial regulators of this process. Loss of HDAC1 and HDAC2 during late T cell development led to the appearance of major histocompatibility complex (MHC) class II-selected CD4(+) helper T cells that expressed CD8-lineage genes such as Cd8a and Cd8b1. HDAC1 and HDAC2-deficient T helper type 0 (TH0) and TH1 cells further upregulated CD8-lineage genes and acquired a CD8(+) effector T cell program in a manner dependent on Runx-CBF? complexes, whereas TH2 cells repressed features of the CD8(+) lineage independently of HDAC1 and HDAC2. These results demonstrate that HDAC1 and HDAC2 maintain integrity of the CD4 lineage by repressing Runx-CBF? complexes that otherwise induce a CD8(+) effector T cell-like program in CD4(+) T cells. PMID:24681565

Boucheron, Nicole; Tschismarov, Roland; Goeschl, Lisa; Moser, Mirjam A; Lagger, Sabine; Sakaguchi, Shinya; Winter, Mircea; Lenz, Florian; Vitko, Dijana; Breitwieser, Florian P; Müller, Lena; Hassan, Hammad; Bennett, Keiryn L; Colinge, Jacques; Schreiner, Wolfgang; Egawa, Takeshi; Taniuchi, Ichiro; Matthias, Patrick; Seiser, Christian; Ellmeier, Wilfried

2014-05-01

6

Histone Deacetylase (HDAC) Activity Is Critical for Embryonic Kidney Gene Expression, Growth, and Differentiation*  

PubMed Central

Histone deacetylases (HDACs) regulate fundamental biological processes such as cellular proliferation, differentiation, and survival via genomic and nongenomic effects. This study examined the importance of HDAC activity in the regulation of gene expression and differentiation of the developing mouse kidney. Class I HDAC1–3 and class II HDAC4, -7, and -9 genes are developmentally regulated. Moreover, HDAC1–3 are highly expressed in nephron precursors. Short term treatment of cultured mouse embryonic kidneys with HDAC inhibitors (HDACi) induced global histone H3 and H4 hyperacetylation and H3K4 hypermethylation. However, genome-wide profiling revealed that the HDAC-regulated transcriptome is restricted and encompasses regulators of the cell cycle, Wnt/?-catenin, TGF-?/Smad, and PI3K-AKT pathways. Further analysis demonstrated that base-line expression of key developmental renal regulators, including Osr1, Eya1, Pax2/8, WT1, Gdnf, Wnt9b, Sfrp1/2, and Emx2, is dependent on intact HDAC activity. Treatment of cultured embryonic kidney cells with HDACi recapitulated these gene expression changes, and chromatin immunoprecipitation assays revealed that HDACi is associated with histone hyperacetylation of Pax2/Pax8, Gdnf, Sfrp1, and p21. Gene knockdown studies demonstrated that HDAC1 and HDAC2 play a redundant role in regulation of Pax2/8 and Sfrp1 but not Gdnf. Long term treatment of embryonic kidneys with HDACi impairs the ureteric bud branching morphogenesis program and provokes growth arrest and apoptosis. We conclude that HDAC activity is critical for normal embryonic kidney homeostasis, and we implicate class I HDACs in the regulation of early nephron gene expression, differentiation, and survival. PMID:21778236

Chen, Shaowei; Bellew, Christine; Yao, Xiao; Stefkova, Jana; Dipp, Susana; Saifudeen, Zubaida; Bachvarov, Dimcho; El-Dahr, Samir S.

2011-01-01

7

The Histone Deacetylase HDAC4 Regulates Long-Term Memory in Drosophila  

PubMed Central

A growing body of research indicates that pharmacological inhibition of histone deacetylases (HDACs) correlates with enhancement of long-term memory and current research is concentrated on determining the roles that individual HDACs play in cognitive function. Here, we investigate the role of HDAC4 in long-term memory formation in Drosophila. We show that overexpression of HDAC4 in the adult mushroom body, an important structure for memory formation, resulted in a specific impairment in long-term courtship memory, but had no affect on short-term memory. Overexpression of an HDAC4 catalytic mutant also abolished LTM, suggesting a mode of action independent of catalytic activity. We found that overexpression of HDAC4 resulted in a redistribution of the transcription factor MEF2 from a relatively uniform distribution through the nucleus into punctate nuclear bodies, where it colocalized with HDAC4. As MEF2 has also been implicated in regulation of long-term memory, these data suggest that the repressive effects of HDAC4 on long-term memory may be through interaction with MEF2. In the same genetic background, we also found that RNAi-mediated knockdown of HDAC4 impairs long-term memory, therefore we demonstrate that HDAC4 is not only a repressor of long-term memory, but also modulates normal memory formation. PMID:24349558

Fitzsimons, Helen L.; Schwartz, Silvia; Given, Fiona M.; Scott, Maxwell J.

2013-01-01

8

Probing phosphorylation-dependent protein interactions within functional domains of histone deacetylase 5 (HDAC5).  

PubMed

Class IIa histone deacetylases (HDACs) are critical transcriptional regulators, shuttling between nuclear and cytoplasmic cellular compartments. Within the nucleus, these HDACs repress transcription as components of multiprotein complexes, such as the nuclear corepressor and beclin-6 corepressor (BCoR) complexes. Cytoplasmic relocalization relieves this transcriptional repressive function. Class IIa HDAC shuttling is controlled, in part, by phosphorylations flanking the nuclear localization signal (NLS). Furthermore, we have reported that phosphorylation within the NLS by the kinase Aurora B modulates the localization and function of the class IIa HDAC5 during mitosis. While we identified numerous additional HDAC5 phosphorylations, their regulatory functions remain unknown. Here, we studied phosphorylation sites within functional HDAC5 domains, including the deacetylation domain (DAC, Ser755), nuclear export signal (NES, Ser1108), and an acidic domain (AD, Ser611). We have generated phosphomutant cell lines to investigate how absence of phosphorylation at these sites impacts HDAC5 localization, enzymatic activity, and protein interactions. Combining molecular biology and quantitative MS, we have defined the interactions and HDAC5-containing complexes mediated by site-specific phosphorylation and quantified selected changes using parallel reaction monitoring. These results expand the current understanding of HDAC regulation, and the functions of this critical family of proteins within human cells. PMID:24920159

Guise, Amanda J; Mathias, Rommel A; Rowland, Elizabeth A; Yu, Fang; Cristea, Ileana M

2014-10-01

9

Histone Deacetylase (HDAC) 10 Suppresses Cervical Cancer Metastasis through Inhibition of Matrix Metalloproteinase (MMP) 2 and 9 Expression*  

PubMed Central

Aberrant expression of histone deacetylases (HDACs) is associated with carcinogenesis. Some HDAC inhibitors are widely considered as promising anticancer therapeutics. A major obstacle for development of HDAC inhibitors as highly safe and effective anticancer therapeutics is that our current knowledge on the contributions of different HDACs in various cancer types remains scant. Here we report that the expression level of HDAC10 was significantly lower in patients exhibiting lymph node metastasis compared with that in patients lacking lymph node metastasis in human cervical squamous cell carcinoma. Forced expression of HDAC10 in cervical cancer cells significantly inhibited cell motility and invasiveness in vitro and metastasis in vivo. Mechanistically, HDAC10 suppresses expression of matrix metalloproteinase (MMP) 2 and 9 genes, which are known to be critical for cancer cell invasion and metastasis. At the molecular level, HDAC10 binds to MMP2 and -9 promoter regions, reduces the histone acetylation level, and inhibits the binding of RNA polymerase II to these regions. Furthermore, an HDAC10 mutant lacking histone deacetylase activity failed to mimic the functions of full-length protein. These results identify a critical role of HDAC10 in suppression of cervical cancer metastasis, underscoring the importance of developing isoform-specific HDAC inhibitors for treatment of certain cancer types such as cervical squamous cell carcinoma. PMID:23897811

Song, Chenlin; Zhu, Songcheng; Wu, Chuanyue; Kang, Jiuhong

2013-01-01

10

Histone Deacetylase 6 (HDAC6) Deacetylates Survivin for Its Nuclear Export in Breast Cancer*  

PubMed Central

Survivin is an oncogenic protein that is highly expressed in breast cancer and has a dual function that is dependent on its subcellular localization. In the cytosol, survivin blocks programmed cell death by inactivating caspase proteins; however, in the nucleus it facilitates cell division by regulating chromosomal movement and cytokinesis. In prior work, we showed that survivin is acetylated by CREB-binding protein (CBP), which restricts its localization to the nuclear compartment and thereby inhibits its anti-apoptotic function. Here, we identify histone deacetylase 6 (HDAC6) as responsible for abrogating CBP-mediated survivin acetylation in the estrogen receptor (ER)-positive breast cancer cell line, MCF-7. HDAC6 directly binds survivin, an interaction that is enhanced by CBP. In quiescent breast cancer cells in culture and in malignant tissue sections from ER+ breast tumors, HDAC6 localizes to a perinuclear region of the cell, undergoing transport to the nucleus following CBP activation where it then deacetylates survivin. Genetically modified mouse embryonic fibroblasts that lack mhdac6 localize survivin predominantly to the nuclear compartment, whereas wild-type mouse embryonic fibroblasts localize survivin to distinct cytoplasmic structures. Together, these data imply that HDAC6 deacetylates survivin to regulate its nuclear export, a feature that may provide a novel target for patients with ER+ breast cancer. PMID:22334690

Riolo, Matthew T.; Cooper, Zachary A.; Holloway, Michael P.; Cheng, Yan; Bianchi, Cesario; Yakirevich, Evgeny; Ma, Li; Chin, Y. Eugene; Altura, Rachel A.

2012-01-01

11

Statins Increase p21 through Inhibition of Histone Deacetylase Activity and Release of Promoter-Associated HDAC1\\/2  

Microsoft Academic Search

Statins are 3-hydroxy-3-methylglutaryl-CoA reductase inhi- bitors broadly used for the control of hypercholesterolemia. Recently, they are reported to have beneficial effects on cer- tain cancers. In this study, we show that statins inhibited the histone deacetylase (HDAC) activity and increased the accumulation of acetylated histone-H3 and the expression of p21WAF\\/CIP in human cancer cells. Computational modeling showed the direct interaction

Yi-Chu Lin; Jung-Hsin Lin; Chia-Wei Chou; Yu-Fan Chang; Shu-Hao Yeh; Ching-Chow Chen

2008-01-01

12

Histone deacetylase (HDAC) 1 and 2 are essential for accurate cell division and the pluripotency of embryonic stem cells.  

PubMed

Histone deacetylases 1 and 2 (HDAC1/2) form the core catalytic components of corepressor complexes that modulate gene expression. In most cell types, deletion of both Hdac1 and Hdac2 is required to generate a discernible phenotype, suggesting their activity is largely redundant. We have therefore generated an ES cell line in which Hdac1 and Hdac2 can be inactivated simultaneously. Loss of HDAC1/2 resulted in a 60% reduction in total HDAC activity and a loss of cell viability. Cell death is dependent upon cell cycle progression, because differentiated, nonproliferating cells retain their viability. Furthermore, we observe increased mitotic defects, chromatin bridges, and micronuclei, suggesting HDAC1/2 are necessary for accurate chromosome segregation. Consistent with a critical role in the regulation of gene expression, microarray analysis of Hdac1/2-deleted cells reveals 1,708 differentially expressed genes. Significantly for the maintenance of stem cell self-renewal, we detected a reduction in the expression of the pluripotent transcription factors, Oct4, Nanog, Esrrb, and Rex1. HDAC1/2 activity is regulated through binding of an inositol tetraphosphate molecule (IP4) sandwiched between the HDAC and its cognate corepressor. This raises the important question of whether IP4 regulates the activity of the complex in cells. By rescuing the viability of double-knockout cells, we demonstrate for the first time (to our knowledge) that mutations that abolish IP4 binding reduce the activity of HDAC1/2 in vivo. Our data indicate that HDAC1/2 have essential and pleiotropic roles in cellular proliferation and regulate stem cell self-renewal by maintaining expression of key pluripotent transcription factors. PMID:24958871

Jamaladdin, Shereen; Kelly, Richard D W; O'Regan, Laura; Dovey, Oliver M; Hodson, Grace E; Millard, Christopher J; Portolano, Nicola; Fry, Andrew M; Schwabe, John W R; Cowley, Shaun M

2014-07-01

13

Macrocyclic Histone Deacetylase Inhibitors  

PubMed Central

Histone deacetylase inhibitors (HDACi) are an emerging class of novel anti-cancer drugs that cause growth arrest, differentiation, and apoptosis of tumor cells. In addition, they have shown promise as anti-parasitic, anti-neurodegenerative, anti-rheumatologic and immunosuppressant agents. To date, several structurally distinct small molecule HDACi have been reported including aryl hydroxamates, benzamides, short-chain fatty acids, electrophilic ketones, and macrocyclic peptides. Macrocyclic HDACi possess the most complex cap-groups which interact with HDAC enzyme’s outer rim and have demonstrated excellent HDAC inhibition potency and isoform selectivity. This review focuses on the recent progress and current state of macrocyclic HDACi. PMID:20536416

Mwakwari, Sandra C.; Patil, Vishal; Guerrant, William; Oyelere, Adegboyega K.

2011-01-01

14

The histone deacetylase (HDAC) inhibitor valproic acid reduces ethanol consumption and ethanol-conditioned place preference in rats.  

PubMed

Recent evidence suggests that epigenetic mechanisms such as chromatin modification (specifically histone acetylation) may play a crucial role in the development of addictive behavior. However, little is known about the role of epigenetic modifications in the rewarding properties of ethanol. In the current study, we studied the effects of systemic injection of the histone deacetylase (HDAC) inhibitor, valproic acid (VPA) on ethanol consumption and ethanol-elicited conditioned place preference (CPP). The effect of VPA (300mg/kg) on voluntary ethanol intake and preference was assessed using continuous two-bottle choice procedure with escalating concentrations of alcohol (2.5-20% v/v escalating over 4 weeks). Taste sensitivity was studies using saccharin (sweet; 0.03% and 0.06%) and quinine (bitter; 20µM and 40µM) tastants solutions. Ethanol conditioned reward was investigated using an unbiased CPP model. Blood ethanol concentration (BEC) was also measured. Compared to vehicle, VPA-injected rats displayed significantly lower preference and consumption of ethanol in a two-bottle choice paradigm, with no significant difference observed with saccharin and quinine. More importantly, 0.5g/kg ethanol-induced-CPP acquisition was blocked following VPA administration. Finally, vehicle- and VPA-treated mice had similar BECs. Taken together, our results implicated HDAC inhibition in the behavioral and reinforcement-related effects of alcohol and raise the question of whether specific drugs that target HDAC could potentially help to tackle alcoholism in humans. PMID:25108044

Al Ameri, Mouza; Al Mansouri, Shamma; Al Maamari, Alyazia; Bahi, Amine

2014-10-01

15

Histone deacetylase (HDAC) Inhibitors Preserve White Matter Structure and Function During Ischemia by Conserving ATP and Reducing Excitotoxicity  

PubMed Central

The importance of white matter (WM) injury to stroke pathology has been underestimated in experimental animal models and this may have contributed to the failure to translate potential therapeutics into the stroke clinic. Histone deacetylase (HDAC) inhibitors are neuroprotective and also promote neurogenesis. These properties make them ideal candidates for stroke therapy. In a pure WM tract (isolated mouse optic nerve) we show that pan- and Class I specific HDAC inhibitors, administered before or after a period of oxygen and glucose deprivation (OGD), promote functional recovery of axons and preserve WM cellular architecture. This protection correlates with the up-regulation of an astrocyte glutamate transporter, delayed and reduced glutamate accumulation during OGD, preservation of axonal mitochondria and oligodendrocytes, and maintenance of ATP levels. Interestingly, the expression of HDACs 1, 2 and 3 is localized to astrocytes, suggesting that changes in glial cell gene transcription and/or protein acetylation may confer protection to axons. Our findings suggest that a therapeutic opportunity exists for the use of HDAC inhibitors, targeting mitochondrial energy regulation and excitotoxicity in ischemic WM injury. PMID:21411642

Baltan, Selva; Murphy, Sean P.; Danilov, Camelia A.; Bachleda, Amelia; Morrison, Richard S.

2011-01-01

16

In silico modification of suberoylanilide hydroxamic acid (SAHA) as potential inhibitor for class II histone deacetylase (HDAC)  

PubMed Central

Background The cervical cancer is the second most prevalent cancer for the woman in the world. It is caused by the oncogenic human papilloma virus (HPV). The inhibition activity of histone deacetylase (HDAC) is a potential strategy for cancer therapy. Suberoylanilide hydroxamic acid (SAHA) is widely known as a low toxicity HDAC inhibitor. This research presents in silico SAHA modification by utilizing triazole, in order to obtain a better inhibitor. We conducted docking of the SAHA inhibitor and 12 modified versions to six class II HDAC enzymes, and then proceeded with drug scanning of each one of them. Results The docking results show that the 12 modified inhibitors have much better binding affinity and inhibition potential than SAHA. Based on drug scan analysis, six of the modified inhibitors have robust pharmacological attributes, as revealed by drug likeness, drug score, oral bioavailability, and toxicity levels. Conclusions The binding affinity, free energy and drug scan screening of the best inhibitors have shown that 1c and 2c modified inhibitors are the best ones to inhibit class II HDAC. PMID:22373132

2011-01-01

17

HIV-1 Tat upregulates expression of histone deacetylase-2 (HDAC2) in human neurons: implication for HIV-associated neurocognitive disorder (HAND).  

PubMed

Histone deacetylases (HDACs) play a pivotal role in epigenetic regulation of transcription and homeostasis of protein acetylation in histones and other proteins involved in chromatin remodeling. Histone hypoacetylation and transcriptional dysfunction have been shown to be associated with a variety of neurodegenerative diseases. More recently, neuron specific overexpression of HDAC2 has been shown to modulate synaptic plasticity and learning behavior in mice. However, the role of HDAC2 in development of HIV-associated neurocognitive disorders (HAND) is not reported. Herein we report that HIV-1 Tat protein upregulate HDAC2 expression in neuronal cells leading to transcriptional repression of genes involved in synaptic plasticity and neuronal function thereby contributing to the progression of HAND. Our results indicate upregulation of HDAC2 by Tat treatment in dose and time dependant manner by human neuroblastoma SK-N-MC cells and primary human neurons. Further, HDAC2 overexpression was associated with concomitant downregulation in CREB and CaMKIIa genes that are known to regulate neuronal activity. These observed effects were completely blocked by HDAC2 inhibition. These results for the first time suggest the possible role of HDAC2 in development of HAND. Therefore, use of HDAC2 specific inhibitor in combination with HAART may be of therapeutic value in treatment of neurocognitive disorders observed in HIV-1 infected individuals. PMID:21315782

Saiyed, Zainulabedin M; Gandhi, Nimisha; Agudelo, Marisela; Napuri, Jessica; Samikkannu, Thangavel; Reddy, Pichili V B; Khatavkar, Pradnya; Yndart, Adriana; Saxena, Shailendra K; Nair, Madhavan P N

2011-05-01

18

Molecular Basis for the Antiparasitic Activity of a Mercaptoacetamide Derivative That Inhibits Histone Deacetylase 8 (HDAC8) from the Human Pathogen Schistosoma mansoni.  

PubMed

Schistosomiasis, caused by the parasitic flatworm Schistosoma mansoni and related species, is a tropical disease that affects over 200 million people worldwide. A new approach for targeting eukaryotic parasites is to tackle their dynamic epigenetic machinery that is necessary for the extensive phenotypic changes during the life cycle of the parasite. Recently, we identified S. mansoni histone deacetylase 8 (smHDAC8) as a potential target for antiparasitic therapy. Here, we present results on the investigations of a focused set of HDAC (histone deacetylase) inhibitors on smHDAC8. Besides several active hydroxamates, we identified a thiol-based inhibitor that inhibited smHDAC8 activity in the micromolar range with unexpected selectivity over the human isotype, which has not been observed so far. The crystal structure of smHDAC8 complexed with the thiol derivative revealed that the inhibitor is accommodated in the catalytic pocket, where it interacts with both the catalytic zinc ion and the essential catalytic tyrosine (Y341) residue via its mercaptoacetamide warhead. To our knowledge, this is the first complex crystal structure of any HDAC inhibited by a mercaptoacetamide inhibitor, and therefore, this finding offers a rationale for further improvement. Finally, an ester prodrug of the thiol HDAC inhibitor exhibited antiparasitic activity on cultured schistosomes in a dose-dependent manner. PMID:24657767

Stolfa, Diana A; Marek, Martin; Lancelot, Julien; Hauser, Alexander-Thomas; Walter, Alexandra; Leproult, Emeline; Melesina, Jelena; Rumpf, Tobias; Wurtz, Jean-Marie; Cavarelli, Jean; Sippl, Wolfgang; Pierce, Raymond J; Romier, Christophe; Jung, Manfred

2014-10-01

19

HDAC8 Substrates: Histones and Beyond  

PubMed Central

The lysine deacetylase family of enzymes (HDACs) was first demonstrated to catalyze deacetylation of acetyllysine residues on histones. In subsequent years, HDACs have been shown to recognize a large pool of acetylated non-histone proteins as substrates. Recently, thousands of acetylated proteins have been discovered, yet in most cases, the HDAC that catalyzes deacetylation in vivo has not been identified. This gap has created the need for better in vivo, in vitro, and in silico approaches for determining HDAC substrates. While HDAC8 is the best kinetically and structurally characterized HDAC, few efficient substrates have yet been substantiated in vivo. In this review we delineate factors that may be important for determining HDAC8 substrate recognition and catalytic activity, including structure, complex formation, and post-translational modifications. This summary provides insight into the challenges of identifying in vivo substrates for HDAC8, and provides a good vantage point for understanding the variables important for predicting HDAC substrate recognition. PMID:23175386

Wolfson, Noah A.; Pitcairn, Carol Ann; Fierke, Carol A.

2012-01-01

20

Structural Basis for the Inhibition of Histone Deacetylase 8 (HDAC8), a Key Epigenetic Player in the Blood Fluke Schistosoma mansoni  

PubMed Central

The treatment of schistosomiasis, a disease caused by blood flukes parasites of the Schistosoma genus, depends on the intensive use of a single drug, praziquantel, which increases the likelihood of the development of drug-resistant parasite strains and renders the search for new drugs a strategic priority. Currently, inhibitors of human epigenetic enzymes are actively investigated as novel anti-cancer drugs and have the potential to be used as new anti-parasitic agents. Here, we report that Schistosoma mansoni histone deacetylase 8 (smHDAC8), the most expressed class I HDAC isotype in this organism, is a functional acetyl-L-lysine deacetylase that plays an important role in parasite infectivity. The crystal structure of smHDAC8 shows that this enzyme adopts a canonical ?/? HDAC fold, with specific solvent exposed loops corresponding to insertions in the schistosome HDAC8 sequence. Importantly, structures of smHDAC8 in complex with generic HDAC inhibitors revealed specific structural changes in the smHDAC8 active site that cannot be accommodated by human HDACs. Using a structure-based approach, we identified several small-molecule inhibitors that build on these specificities. These molecules exhibit an inhibitory effect on smHDAC8 but show reduced affinity for human HDACs. Crucially, we show that a newly identified smHDAC8 inhibitor has the capacity to induce apoptosis and mortality in schistosomes. Taken together, our biological and structural findings define the framework for the rational design of small-molecule inhibitors specifically interfering with schistosome epigenetic mechanisms, and further support an anti-parasitic epigenome targeting strategy to treat neglected diseases caused by eukaryotic pathogens. PMID:24086136

Marek, Martin; Kannan, Srinivasaraghavan; Hauser, Alexander-Thomas; Moraes Mourao, Marina; Caby, Stephanie; Cura, Vincent; Stolfa, Diana A.; Schmidtkunz, Karin; Lancelot, Julien; Andrade, Luiza; Renaud, Jean-Paul; Oliveira, Guilherme; Sippl, Wolfgang; Jung, Manfred; Cavarelli, Jean; Pierce, Raymond J.; Romier, Christophe

2013-01-01

21

HDAC6 ?-tubulin deacetylase: A potential therapeutic target in neurodegenerative diseases  

Microsoft Academic Search

Histone deacetylases (HDACs), or lysine deacetylases (KDAC), are epigenetic regulators that catalyze the removal of acetyl moieties from the tails of lysine residues of histones and other proteins. To date, eighteen HDAC family members (HDAC1-11 and SIRT1-7) have been identified and grouped into four classes according to their homology to yeast histone deacetylases. HDACs play an important role in regulating

Guoyi Li; Huiyi Jiang; Ming Chang; Hongrong Xie; Linsen Hu

2011-01-01

22

Histone Deacetylase Inhibition with Valproic Acid Downregulates Osteocalcin Gene Expression in Human Dental Pulp Stem Cells and Osteoblasts: Evidence for HDAC2 Involvement  

PubMed Central

Adult mesenchymal stem cells, such as dental pulp stem cells, are of great interest for cell-based tissue engineering strategies because they can differentiate into a variety of tissue-specific cells, above all, into osteoblasts. In recent years, epigenetic studies on stem cells have indicated that specific histone alterations and modifying enzymes play essential roles in cell differentiation. However, although several studies have reported that valproic acid (VPA)—a selective inhibitor of histone deacetylases (HDAC)—enhances osteoblast differentiation, data on osteocalcin expression—a late-stage marker of differentiation—are limited. We therefore decided to study the effect of VPA on dental pulp stem cell differentiation. A low concentration of VPA did not reduce cell viability, proliferation, or cell cycle profile. However, it was sufficient to significantly enhance matrix mineralization by increasing osteopontin and bone sialoprotein expression. In contrast, osteocalcin levels were decreased, an effect induced at the transcriptional level, and were strongly correlated with inhibition of HDAC2. In fact, HDAC2 silencing with shRNA produced a similar effect to that of VPA treatment on the expression of osteoblast-related markers. We conclude that VPA does not induce terminal differentiation of osteoblasts, but stimulates the generation of less mature cells. Moreover, specific suppression of an individual HDAC by RNA interference could enhance only a single aspect of osteoblast differentiation, and thus produce selective effects. PMID:24105979

Paino, Francesca; la Noce, Marcel; Tirino, Virginia; Naddeo, Pasqualina; Desiderio, Vincenzo; Pirozzi, Giuseppe; De Rosa, Alfredo; Laino, Luigi; Altucci, Lucia; Papaccio, Gianpaolo

2014-01-01

23

Crosstalk between lysine-specific demethylase 1 (LSD1) and histone deacetylases mediates antineoplastic efficacy of HDAC inhibitors in human breast cancer cells  

PubMed Central

Our previous studies demonstrated that lysine-specific demethylase 1 (LSD1) and histone deacetylases (HDACs) closely interact in controlling growth of breast cancer cells. However, the underlying mechanisms are largely unknown. In this study, we showed that knockdown of LSD1 expression (LSD1-KD) by RNAi decreased mRNA levels of HDAC isozymes in triple-negative breast cancer (TNBC) cells. Small interfering RNA (siRNA)-mediated depletion of HDAC5 expression induced the most significant accumulation of H3K4me2, a specific substrate of LSD1. Combined treatment with LSD1 inhibitor, pargyline, and HDAC inhibitor, SAHA (Vorinostat), led to superior growth inhibition and apoptotic death in TNBC cells, but exhibited additive or antagonistic effect on growth inhibition in non-TNBC counterparts or non-tumorigenic breast cells. Additionally, LSD1-KD enhanced SAHA-induced reexpression of a subset of aberrantly silenced genes, such as NR4A1, PCDH1, RGS16, BIK, and E-cadherin whose reexpression may be tumor suppressive. Genome-wide microarray study in MDA-MB-231 cells identified a group of tumor suppressor genes whose expression was induced by SAHA and significantly enhanced by LSD1-KD. We also showed that concurrent depletion of RGS16 by siRNA reduced overall cytotoxicity of SAHA and blocked the reexpression of E-cadherin, CDKN1C and ING1 in LSD1-deficient MDA-MB-231 cells. Furthermore, cotreatment with RGS16 siRNA reversed the downregulation of nuclear factor-kappaB expression induced by combined inhibition of LSD1 and HDACs, suggesting a crucial role of RGS16 in controlling key pathways of cell death in response to combination therapy. Taken together, these results provide novel mechanistic insight into the breast cancer subtype-dependent role of LSD1 in mediating HDAC activity and therapeutic efficacy of HDAC inhibitor. PMID:23354309

Vasilatos, Shauna N.; Katz, Tiffany A.; Huang, Yi

2013-01-01

24

Limited proteolysis of human histone deacetylase 1  

PubMed Central

Background Histone deacetylase (HDAC) proteins are associated with cell proliferation, differentiation, apoptosis, and cancer. Specifically, HDAC1 is linked with cell growth, a hallmark of cancer formation. HDAC1 is a phosphoprotein and phosphorylation at S421 and S423 promotes HDAC1 enzymatic activity and protein association. While single and double point mutants of HDAC1 at S421 and S423 appear functionally similar, the evidence suggests that HDAC1 is phosphorylated simultaneously at both S421 and S423 in vivo. Additional experiments are necessary to probe the role of double phosphorylation of HDAC1 at S421 and S423. Results To characterize HDAC1 phosphorylation at S421 and S423, limited proteolysis of HDAC1 was performed for the first time. HDAC1 degraded without production of discrete fragments. By performing concentration-dependent proteolysis, HDAC1 double point mutants with disrupted phosphorylation at S421 and S423 displayed different trypsin sensitivities compared to wild type HDAC1. Unexpectedly, HDAC1 single point mutants with disrupted phosphorylation at either S421 or S423 demonstrated protease sensitivity similar to the wild type HDAC1. Conclusion Concentration-dependent proteolysis experiments provide evidence that phosphorylation of S421 and S423 individually contribute to HDAC1 function. In addition, the limited proteolysis experiments support a model where associated proteins promote HDAC1 enzymatic activity, reinforcing the importance of protein interactions in HDAC1 structure and function. Finally, because HDAC1 does not display distinct regions of protease sensitivity, the proteolysis studies suggest that HDAC1 comprises inter-related structural regions. PMID:17022812

Kamath, Nayana; Karwowska-Desaulniers, Paulina; Pflum, Mary Kay H

2006-01-01

25

Design, synthesis, and evaluation of hydroxamic acid-based molecular probes for in vivo imaging of histone deacetylase (HDAC) in brain  

PubMed Central

Hydroxamic acid-based histone deacetylase inhibitors (HDACis) are a class of molecules with therapeutic potential currently reflected in the use of suberoylanilide hydroxamic acid (SAHA; Vorinostat) to treat cutaneous T-cell lymphomas (CTCL). HDACis may have utility beyond cancer therapy, as preclinical studies have ascribed HDAC inhibition as beneficial in areas such as heart disease, diabetes, depression, neurodegeneration, and other disorders of the central nervous system (CNS). However, little is known about the pharmacokinetics (PK) of hydroxamates, particularly with respect to CNS-penetration, distribution, and retention. To explore the rodent and non-human primate (NHP) brain permeability of hydroxamic acid-based HDAC inhibitors using positron emission tomography (PET), we modified the structures of belinostat (PXD101) and panobinostat (LBH-589) to incorporate carbon-11. We also labeled PCI 34051 through carbon isotope substitution. After characterizing the in vitro affinity and efficacy of these compounds across nine recombinant HDAC isoforms spanning Class I and Class II family members, we determined the brain uptake of each inhibitor. Each labeled compound has low uptake in brain tissue when administered intravenously to rodents and NHPs. In rodent studies, we observed that brain accumulation of the radiotracers were unaffected by the pre-administration of unlabeled inhibitors. Knowing that CNS-penetration may be desirable for both imaging applications and therapy, we explored whether a liquid chromatography, tandem mass spectrometry (LC-MS-MS) method to predict brain penetrance would be an appropriate method to pre-screen compounds (hydroxamic acid-based HDACi) prior to PET radiolabeling. LC-MS-MS data were indeed useful in identifying additional lead molecules to explore as PET imaging agents to visualize HDAC enzymes in vivo. However, HDACi brain penetrance predicted by LC-MS-MS did not strongly correlate with PET imaging results. This underscores the importance of in vivo PET imaging tools in characterizing putative CNS drug lead compounds and the continued need to discover effect PET tracers for neuroepigenetic imaging. PMID:24380043

Wang, Changning; Eessalu, Thomas E; Barth, Vanessa N; Mitch, Charles H; Wagner, Florence F; Hong, Yijia; Neelamegam, Ramesh; Schroeder, Frederick A; Holson, Edward B; Haggarty, Stephen J; Hooker, Jacob M

2014-01-01

26

Histone deacetylase inhibitors (HDACIs): multitargeted anticancer agents  

PubMed Central

Histone deacetylase (HDAC) inhibitors are an emerging class of therapeutics with potential as anticancer drugs. The rationale for developing HDAC inhibitors (and other chromatin-modifying agents) as anticancer therapies arose from the understanding that in addition to genetic mutations, epigenetic changes such as dysregulation of HDAC enzymes can alter phenotype and gene expression, disturb homeostasis, and contribute to neoplastic growth. The family of HDAC inhibitors is large and diverse. It includes a range of naturally occurring and synthetic compounds that differ in terms of structure, function, and specificity. HDAC inhibitors have multiple cell type-specific effects in vitro and in vivo, such as growth arrest, cell differentiation, and apoptosis in malignant cells. HDAC inhibitors have the potential to be used as monotherapies or in combination with other anticancer therapies. Currently, there are two HDAC inhibitors that have received approval from the US FDA for the treatment of cutaneous T-cell lymphoma: vorinostat (suberoylanilide hydroxamic acid, Zolinza) and depsipeptide (romidepsin, Istodax). More recently, depsipeptide has also gained FDA approval for the treatment of peripheral T-cell lymphoma. Many more clinical trials assessing the effects of various HDAC inhibitors on hematological and solid malignancies are currently being conducted. Despite the proven anticancer effects of particular HDAC inhibitors against certain cancers, many aspects of HDAC enzymes and HDAC inhibitors are still not fully understood. Increasing our understanding of the effects of HDAC inhibitors, their targets and mechanisms of action will be critical for the advancement of these drugs, especially to facilitate the rational design of HDAC inhibitors that are effective as antineoplastic agents. This review will discuss the use of HDAC inhibitors as multitargeted therapies for malignancy. Further, we outline the pharmacology and mechanisms of action of HDAC inhibitors while discussing the safety and efficacy of these compounds in clinical studies to date. PMID:23459471

Ververis, Katherine; Hiong, Alison; Karagiannis, Tom C; Licciardi, Paul V

2013-01-01

27

Dendritic cell development requires histone deacetylase activity  

PubMed Central

DCs develop from multipotent progenitors (MPPs), which commit into DC-restricted common dendritic cell progenitors (CDPs). CDPs further differentiate into classical DCs (cDCs) and plasmacytoid DCs (pDCs). Here, we studied the impact of histone acetylation on DC development in C57BL/6 mice by interfering with histone acetylation and deacetylation, employing histone deacetylase (HDAC) inhibitors. We observed that commitment of MPPs into CDPs was attenuated by HDAC inhibition and that pDC development was specifically blocked. Gene expression profiling revealed that HDAC inhibition prevents establishment of a DC-specific gene expression repertoire. Importantly, protein levels of the core DC transcription factor PU.1 were reduced in HDAC inhibitor-treated cells and consequently PU.1 recruitment at PU.1 target genes Fms-like tyrosine kinase 3 (Flt3), interferon regulatory factor 8 (IRF8), and PU.1 itself was impaired. Thus, our results demonstrate that attenuation of PU.1 expression by HDAC inhibition causes reduced expression of key DC regulators, which results in attenuation of DC development. We propose that chromatin modifiers, such as HDACs, are required for establishing a DC gene network, where Flt3/STAT3 signaling drives PU.1 and IRF8 expression and DC development. Taken together, our study identifies HDACs as critical regulators of DC lineage commitment and development. PMID:24810486

Chauvistré, Heike; Küstermann, Caroline; Rehage, Nina; Klisch, Theresa; Mitzka, Saskia; Felker, Piritta; Rose-John, Stefan; Zenke, Martin; Seré, Kristin M

2014-01-01

28

Mice Lacking Histone Deacetylase 6 Have Hyperacetylated Tubulin but Are Viable and Develop Normally  

Microsoft Academic Search

Posttranslational modifications play important roles in regulating protein structure and function. Histone deacetylase 6 (HDAC6) is a mostly cytoplasmic class II HDAC, which has a unique structure with two catalytic domains and a domain binding ubiquitin with high affinity. This enzyme was recently identified as a multi- substrate protein deacetylase that can act on acetylated histone tails, -tubulin and Hsp90.

Yu Zhang; SoHee Kwon; Teppei Yamaguchi; Fabien Cubizolles; Sophie Rousseaux; Michaela Kneissel; Chun Cao; Na Li; Hwei-Ling Cheng; Katrin Chua; David Lombard; Adam Mizeracki; Gabriele Matthias; Frederick W. Alt; Saadi Khochbin; Patrick Matthias

2008-01-01

29

Histone deacetylase 1 (HDAC1) participates in the down-regulation of corticotropin releasing hormone gene (crh) expression.  

PubMed

The paraventricular nucleus of the hypothalamus (PVH) plays a central role in regulating the hypothalamic-pituitary-adrenal (HPA) axis. Medial parvocellular neurons of the PVH (mpPVH) integrate sensory and humoral inputs to maintain homeostasis. Humoral inputs include glucocorticoids secreted by the adrenals, which down-regulate HPA activation. A primary glucocorticoid target is the population of mpPVH neurons that synthesize and secrete corticotropin-releasing factors, the most potent of which is corticotropin-releasing hormone (CRH). Although CRH gene (crh) expression is known to be down-regulated by glucocorticoids, the mechanisms by which this process occurs are still poorly understood. To begin this study we postulated that glucocorticoid repression of crh involves HDAC recruitment to the region of the crh proximal promoter. To evaluate this hypothesis, we treated hypothalamic cells that express CRH with the HDAC inhibitor trichostatin A (TSA). As predicted, treatment with TSA led to increased CRH mRNA levels and crh promoter activity. Although co-treatment with Dex (10(-7)M) reduced the TSA effect on mRNA levels, it failed to reduce promoter activity; however co-transfection of HDAC1 but not 3 restored Dex inhibition. A distinction between HDAC1 and 3 was also apparent with respect to crh promoter occupancy. Dex led to increased HDAC1 but not HDAC3 occupancy. In vivo studies revealed that CRH-immunoreactive (-ir) neurons contained HDAC1- and HDAC3-ir. Collectively, these data point to a role for HDAC1 in the physiologic regulation of crh. PMID:21463644

Miller, Lydia; Foradori, Chad D; Lalmansingh, Avin S; Sharma, Dharmendra; Handa, Robert J; Uht, Rosalie M

2011-08-01

30

Interplay between histone deacetylases and autophagy - from cancer therapy to neurodegeneration  

Microsoft Academic Search

Histone deacetylases (HDACs) are chromatin modifiers that alter gene expression but also exert a broad range of functions outside the nucleus by deacetylating non-histone target proteins. They gained growing attention for their implications in disease treatment, mainly through research using HDAC-inhibiting compounds. Understanding the effects of HDAC function and deregulation has therefore become an important focus for both basic and

Oliver Trüe; Patrick Matthias

2012-01-01

31

Histone deacetylase complexes promote trinucleotide repeat expansions.  

PubMed

Expansions of DNA trinucleotide repeats cause at least 17 inherited neurodegenerative diseases, such as Huntington's disease. Expansions can occur at frequencies approaching 100% in affected families and in transgenic mice, suggesting that specific cellular proteins actively promote (favor) expansions. The inference is that expansions arise due to the presence of these promoting proteins, not their absence, and that interfering with these proteins can suppress expansions. The goal of this study was to identify novel factors that promote expansions. We discovered that specific histone deacetylase complexes (HDACs) promote CTG•CAG repeat expansions in budding yeast and human cells. Mutation or inhibition of yeast Rpd3L or Hda1 suppressed up to 90% of expansions. In cultured human astrocytes, expansions were suppressed by 75% upon inhibition or knockdown of HDAC3, whereas siRNA against the histone acetyltransferases CBP/p300 stimulated expansions. Genetic and molecular analysis both indicated that HDACs act at a distance from the triplet repeat to promote expansions. Expansion assays with nuclease mutants indicated that Sae2 is one of the relevant factors regulated by Rpd3L and Hda1. The causal relationship between HDACs and expansions indicates that HDACs can promote mutagenesis at some DNA sequences. This relationship further implies that HDAC3 inhibitors being tested for relief of expansion-associated gene silencing may also suppress somatic expansions that contribute to disease progression. PMID:22363205

Debacker, Kim; Frizzell, Aisling; Gleeson, Olive; Kirkham-McCarthy, Lucy; Mertz, Tony; Lahue, Robert S

2012-02-01

32

Histone Deacetylase: A Potential Therapeutic Target for Fibrotic Disorders  

PubMed Central

Histone deacetylases (HDACs) are enzymes that balance the acetylation activities of histone acetyltransferases on chromatin remodeling and play essential roles in regulating gene transcription. In the past several years, the role of HDACs in cancer initiation and progression, as well as the therapeutic effects of HDAC inhibitors in various types of cancer, has been well studied. Recent studies indicated that HDAC activity is also associated with the development and progression of some chronic diseases characterized by fibrosis, including chronic kidney disease, cardiac hypertrophy, and idiopathic pulmonary fibrosis. Here, we review what is known about HDACs in the progression of tissue fibrosis and the potential applications of HDAC inhibitors in the treatment of disorders associated with fibroblast activation and proliferation. PMID:20719940

Pang, Maoyin

2010-01-01

33

Histone Deacetylase Inhibitors: A Novel Therapeutic Approach for Cognitive Disorders  

Microsoft Academic Search

\\u000a Epigenetic mechanisms have a central role in regulating gene expression and are capable of influencing complex cognitive functions.\\u000a In particular, acetylation of histone proteins is an epigenetic modification involved in mediating synaptic plasticity, learning,\\u000a and memory. Emerging evidence indicates that increased histone acetylation through the inhibition of histone deacetylases\\u000a (HDACs) can facilitate the formation of long-term memories in preclinical studies.

Viviane Labrie

34

Stimulation of Histone Deacetylase Activity by Metabolites of Intermediary Metabolism*  

PubMed Central

Histone deacetylases (HDACs) function in a wide range of molecular processes, including gene expression, and are of significant interest as therapeutic targets. Although their native complexes, subcellular localization, and recruitment mechanisms to chromatin have been extensively studied, much less is known about whether the enzymatic activity of non-sirtuin HDACs can be regulated by natural metabolites. Here, we show that several coenzyme A (CoA) derivatives, such as acetyl-CoA, butyryl-CoA, HMG-CoA, and malonyl-CoA, as well as NADPH but not NADP+, NADH, or NAD+, act as allosteric activators of recombinant HDAC1 and HDAC2 in vitro following a mixed activation kinetic. In contrast, free CoA, like unconjugated butyrate, inhibits HDAC activity in vitro. Analysis of a large number of engineered HDAC1 mutants suggests that the HDAC activity can potentially be decoupled from “activatability” by the CoA derivatives. In vivo, pharmacological inhibition of glucose-6-phosphate dehydrogenase (G6PD) to decrease NADPH levels led to significant increases in global levels of histone H3 and H4 acetylation. The similarity in structures of the identified metabolites and the exquisite selectivity of NADPH over NADP+, NADH, and NAD+ as an HDAC activator reveal a previously unrecognized biochemical feature of the HDAC proteins with important consequences for regulation of histone acetylation as well as the development of more specific and potent HDAC inhibitors. PMID:22822071

Vogelauer, Maria; Krall, Abigail S.; McBrian, Matthew A.; Li, Jing-Yu; Kurdistani, Siavash K.

2012-01-01

35

Therapeutic application of histone deacetylase inhibitors for central nervous system disorders  

Microsoft Academic Search

Histone deacetylases (HDACs) — enzymes that affect the acetylation status of histones and other important cellular proteins — have been recognized as potentially useful therapeutic targets for a broad range of human disorders. Pharmacological manipulations using small-molecule HDAC inhibitors — which may restore transcriptional balance to neurons, modulate cytoskeletal function, affect immune responses and enhance protein degradation pathways — have

Leslie M. Thompson; Aleksey G. Kazantsev

2008-01-01

36

Linking epigenetics to lipid metabolism: focus on histone deacetylases.  

PubMed

A number of recent studies revealed that epigenetic modifications play a central role in the regulation of lipid and of other metabolic pathways such as cholesterol homeostasis, bile acid synthesis, glucose and energy metabolism. Epigenetics refers to aspects of genome functions regulated in a DNA sequence-independent fashion. Chromatin structure is controlled by epigenetic mechanisms through DNA methylation and histone modifications. The main modifications are histone acetylation and deacetylation on specific lysine residues operated by two different classes of enzymes: Histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively. The interaction between these enzymes and histones can activate or repress gene transcription: Histone acetylation opens and activates chromatin, while deacetylation of histones and DNA methylation compact chromatin making it transcriptionally silent. The new evidences on the importance of HDACs in the regulation of lipid and other metabolic pathways will open new perspectives in the comprehension of the pathophysiology of metabolic disorders. PMID:23095054

Ferrari, Alessandra; Fiorino, Erika; Giudici, Marco; Gilardi, Federica; Galmozzi, Andrea; Mitro, Nico; Cermenati, Gaia; Godio, Cristina; Caruso, Donatella; De Fabiani, Emma; Crestani, Maurizio

2012-11-01

37

Histone Deacetylase 5 Limits Cocaine Reward through cAMP-Induced Nuclear Import  

E-print Network

Chromatin remodeling by histone deacetylases (HDACs) is a key mechanism regulating behavioral adaptations to cocaine use. We report here that cocaine and cyclic adenosine monophosphate (cAMP) signaling induce the transient ...

Taniguchi, Makoto

38

Histone Deacetylase 1 and p300 Can Directly Associate with Chromatin and Compete for Binding in a Mutually Exclusive Manner  

PubMed Central

Lysine acetyltransferases (KATs) and histone deacetylases (HDACs) are important epigenetic modifiers and dynamically cycled on active gene promoters to regulate transcription. Although HDACs are recruited to gene promoters and DNA hypersensitive sites through interactions with DNA binding factors, HDAC activities are also found globally in intergenic regions where DNA binding factors are not present. It is suggested that HDACs are recruited to those regions through other distinct, yet undefined mechanisms. Here we show that HDACs can be directly recruited to chromatin in the absence of other factors through direct interactions with both DNA and core histone subunits. HDACs interact with DNA in a non-sequence specific manner. HDAC1 and p300 directly bind to the overlapping regions of the histone H3 tail and compete for histone binding. Previously we show that p300 can acetylate HDAC1 to attenuate deacetylase activity. Here we have further mapped two distinct regions of HDAC1 that interact with p300. Interestingly, these regions of HDAC1 also associate with histone H3. More importantly, p300 and HDAC1 compete for chromatin binding both in vitro and in vivo. Therefore, the mutually exclusive associations of HDAC1/p300, p300/histone, and HDAC1/histone on chromatin contribute to the dynamic regulation of histone acetylation by balancing HDAC or KAT activity present at histones to reorganize chromatin structure and regulate transcription. PMID:24722339

Li, Xuehui; Yang, Hui; Huang, Suming; Qiu, Yi

2014-01-01

39

Loss of Epigenetic Kruppel-like Factor 4 Histone Deacetylase (KLF-4-HDAC)-mediated Transcriptional Suppression Is Crucial in Increasing Vascular Endothelial Growth Factor (VEGF) Expression in Breast Cancer*  

PubMed Central

Vascular endothelial growth factor (VEGF) is recognized as an important angiogenic factor that promotes angiogenesis in a series of pathological conditions, including cancer, inflammation, and ischemic disorders. We have recently shown that the inflammatory transcription factor SAF-1 is, at least in part, responsible for the marked increase of VEGF levels in breast cancer. Here, we show that SAF-1-mediated induction of VEGF is repressed by KLF-4 transcription factor. KLF-4 is abundantly present in normal breast epithelial cells, but its level is considerably reduced in breast cancer cells and clinical cancer tissues. In the human VEGF promoter, SAF-1- and KLF-4-binding elements are overlapping, whereas SAF-1 induces and KLF-4 suppresses VEGF expression. Ectopic overexpression of KLF-4 and RNAi-mediated inhibition of endogenous KLF-4 supported the role of KLF-4 as a transcriptional repressor of VEGF and an inhibitor of angiogenesis in breast cancer cells. We show that KLF-4 recruits histone deacetylases (HDACs) -2 and -3 at the VEGF promoter. Chronological ChIP assays demonstrated the occupancy of KLF-4, HDAC2, and HDAC3 in the VEGF promoter in normal MCF-10A cells but not in MDA-MB-231 cancer cells. Co-transfection of KLF-4 and HDAC expression plasmids in breast cancer cells results in synergistic repression of VEGF expression and inhibition of angiogenic potential of these carcinoma cells. Together these results identify a new mechanism of VEGF up-regulation in cancer that involves concomitant loss of KLF-4-HDAC-mediated transcriptional repression and active recruitment of SAF-1-mediated transcriptional activation. PMID:23926105

Ray, Alpana; Alalem, Mohamed; Ray, Bimal K.

2013-01-01

40

Histone deacetylase inhibitors as potential treatment for spinal muscular atrophy  

PubMed Central

Histone acetylation plays an important role in regulation of transcription in eukaryotic cells by promoting a more relaxed chromatin structure necessary for transcriptional activation. Histone deacetylases (HDACs) remove acetyl groups and suppress gene expression. HDAC inhibitors (HDACIs) are a group of small molecules that promote gene transcription by chromatin remodeling and have been extensively studied as potential drugs for treating of spinal muscular atrophy. Various drugs in this class have been studied with regard to their efficacy in increasing the expression of survival of motor neuron (SMN) protein. In this review, we discuss the current literature on this topic and summarize the findings of the main studies in this field. PMID:24130434

Mohseni, Jafar; Zabidi-Hussin, Z.A.M.H.; Sasongko, Teguh Haryo

2013-01-01

41

Histone Deacetylase 3 Depletion in Osteo\\/Chondroprogenitor Cells Decreases Bone Density and Increases Marrow Fat  

Microsoft Academic Search

Histone deacetylase (Hdac)3 is a nuclear enzyme that contributes to epigenetic programming and is required for embryonic development. To determine the role of Hdac3 in bone formation, we crossed mice harboring loxP sites around exon 7 of Hdac3 with mice expressing Cre recombinase under the control of the osterix promoter. The resulting Hdac3 conditional knockout (CKO) mice were runted and

David F. Razidlo; Tiffany J. Whitney; Michelle E. Casper; Meghan E. McGee-Lawrence; Bridget A. Stensgard; Xiaodong Li; Frank J. Secreto; Sarah K. Knutson; Scott W. Hiebert; Jennifer J. Westendorf; Sudha Agarwal

2010-01-01

42

Histone deacetylase inhibitors from the rhizomes of Zingiber zerumbet.  

PubMed

Histone acetylation and deacetylation play fundamental roles in the modulation of chromatin topology and the regulation of gene transcription. Histone deacetylase (HDAC) inhibitors that inhibit proliferation and induce differentiation and/or apoptosis of tumor cells in culture and in animal models have been identified. A number of structurally diverse histone deacetylase inhibitors have shown potent antitumor efficacy with little toxicity in vivo in animal models. In the context of our natural product chemistry program dealing with the development of new potent anticancer agents, we have examined the isolation from Zingiber zerumbet as leads for novel HDAC inhibitors. Zingiber zerumbet (L.) J. E. Smith (Zingiberaceae) is a wild ginger that typically grows widely in Southeast Asia. Isolation of the n-hexane soluble fraction from Zingiber zerumbet yielded two major sesequiterpenoids, 6-methoxy-2E,9E-humuladien-8-one (1) and zerumbone (2). The structures were elucidated on the basis of spectroscopic data. The histone deacetylase (HDAC) activities of compounds 1 and 2 were determined in vitro against HDAC enzyme assay. Compound 1 exhibited growth inhibitory activity on six human tumor cell lines, and showed potential inhibitory activity in histone deacetylase (HDAC) enzyme assay (GI50 = 1.25 microM). It also exhibited growth inhibitory activity on five human tumor cell lines and more sensitive inhibitory activity on the MDA-MB-231 breast tumor cell line (IC50 = 1.45 microM). Further structure-activity relationships of position C-6 and C-7 from aromatic ring will be reported in due course. PMID:18972844

Chung, Ill-Min; Kim, Min-Young; Park, Won-Hwan; Moon, Hyung-In

2008-10-01

43

The functional interactome landscape of the human histone deacetylase family  

PubMed Central

Histone deacetylases (HDACs) are a diverse family of essential transcriptional regulatory enzymes, that function through the spatial and temporal recruitment of protein complexes. As the composition and regulation of HDAC complexes are only partially characterized, we built the first global protein interaction network for all 11 human HDACs in T cells. Integrating fluorescence microscopy, immunoaffinity purifications, quantitative mass spectrometry, and bioinformatics, we identified over 200 unreported interactions for both well-characterized and lesser-studied HDACs, a subset of which were validated by orthogonal approaches. We establish HDAC11 as a member of the survival of motor neuron complex and pinpoint a functional role in mRNA splicing. We designed a complementary label-free and metabolic-labeling mass spectrometry-based proteomics strategy for profiling interaction stability among different HDAC classes, revealing that HDAC1 interactions within chromatin-remodeling complexes are largely stable, while transcription factors preferentially exist in rapid equilibrium. Overall, this study represents a valuable resource for investigating HDAC functions in health and disease, encompassing emerging themes of HDAC regulation in cell cycle and RNA processing and a deeper functional understanding of HDAC complex stability. PMID:23752268

Joshi, Preeti; Greco, Todd M; Guise, Amanda J; Luo, Yang; Yu, Fang; Nesvizhskii, Alexey I; Cristea, Ileana M

2013-01-01

44

Dimethyl fumarate regulates histone deacetylase expression in astrocytes.  

PubMed

We previously showed that dimethyl fumarate (DMF) reduces inflammatory activation in astrocytes, involving activation of transcription factor Nrf2. However, the pathways causing Nrf2 activation were not examined. We now show that DMF modifies expression of histone deacetylases (HDACs) in primary rat astrocytes. After 4h incubation, levels of HDAC1, 2, and 4 mRNAs were increased by DMF; however, after 24h, levels returned to or were below control values. At that time, HDAC protein levels and overall activity were also reduced by DMF. Stimulation of astrocytes with pro-inflammatory cytokines significantly increased HDAC mRNA levels after 24h, although protein levels were not increased at that time point. In the presence of cytokines, DMF reduced HDAC mRNAs, proteins, and activity. Proteomic analysis of DMF-treated astrocytes identified 8 proteins in which lysine acetylation was increased by DMF, including histones H2a.1 and H3.3. A role for HDACs in mediating DMF actions is suggested by findings that the selective HDAC inhibitor SAHA increased nuclear Nrf2:DNA binding activity, reduced inflammatory activation of astrocytes which was reversed by a selective inhibitor of the Nrf2 target gene heme-oxygenase 1. These data show that DMF regulates astrocyte HDAC expression, which could contribute to Nrf2 activation, suppression of inflammatory responses and cause long-lasting changes in gene expression. PMID:23916696

Kalinin, Sergey; Polak, Paul E; Lin, Shao Xia; Braun, David; Guizzetti, Marina; Zhang, Xiaolu; Rubinstein, Israel; Feinstein, Douglas L

2013-10-15

45

Interpreting clinical assays for histone deacetylase inhibitors  

PubMed Central

As opposed to genetics, dealing with gene expressions by direct DNA sequence modifications, the term epigenetics applies to all the external influences that target the chromatin structure of cells with impact on gene expression unrelated to the sequence coding of DNA itself. In normal cells, epigenetics modulates gene expression through all development steps. When “imprinted” early by the environment, epigenetic changes influence the organism at an early stage and can be transmitted to the progeny. Together with DNA sequence alterations, DNA aberrant cytosine methylation and microRNA deregulation, epigenetic modifications participate in the malignant transformation of cells. Their reversible nature has led to the emergence of the promising field of epigenetic therapy. The efforts made to inhibit in particular the epigenetic enzyme family called histone deacetylases (HDACs) are described. HDAC inhibitors (HDACi) have been proposed as a viable clinical therapeutic approach for the treatment of leukemia and solid tumors, but also to a lesser degree for noncancerous diseases. Three epigenetic drugs are already arriving at the patient’s bedside, and more than 100 clinical assays for HDACi are registered on the National Cancer Institute website. They explore the eventual additive benefits of combined therapies. In the context of the pleiotropic effects of HDAC isoforms, more specific HDACi and more informative screening tests are being developed for the benefit of the patients. PMID:21625397

Martinet, Nadine; Bertrand, Philippe

2011-01-01

46

Transcriptional induction of GRP78/BiP by histone deacetylase inhibitors and resistance to histone deacetylase inhibitor-induced apoptosis  

PubMed Central

Histone deacetylase (HDAC) inhibitors are emerging as effective therapies in the treatment of cancer, and the role of HDACs in the regulation of promoters is rapidly expanding. GRP78/BiP is a stress inducible endoplasmic reticulum (ER) chaperone with anti-apoptotic properties. We present here the mechanism for repression of the Grp78 promoter by histone deacetylase 1 (HDAC1). Our studies reveal that HDAC inhibitors specifically induce GRP78, and the induction level is amplified by ER stress. Through mutational analysis, we have identified the minimal Grp78 promoter and specific elements responsible for HDAC-mediated repression. We show the involvement of HDAC1 in the negative regulation of the Grp78 promoter not only by its induction in the presence of the HDAC inhibitors trichostatin A and MS-275, but also by exogenous overexpression and siRNA knockdown of specific HDACs. We present the results of chromatin immunoprecipitation analysis that reveals the binding of HDAC1 to the Grp78 promoter before but not after ER stress. Furthermore, overexpression of GRP78 confers resistance to HDAC inhibitor induced apoptosis in cancer cells and, conversely, suppression of GRP78 sensitizes them to HDAC inhibitor. These results define HDAC inhibitors as new agents that upregulate GRP78 without concomitantly inducing the ER or heat shock stress response, and suppression of GRP78 in tumors may provide a novel, adjunctive option to enhance anti-cancer therapies that utilize these compounds. PMID:19417144

Baumeister, Peter; Dong, Dezheng; Fu, Yong; Lee, Amy S.

2009-01-01

47

Mitochondrial Apoptosis and FAK Signaling Disruption by a Novel Histone Deacetylase Inhibitor, HTPB, in Antitumor and Antimetastatic Mouse Models  

Microsoft Academic Search

BackgroundCompound targeting histone deacetylase (HDAC) represents a new era in molecular cancer therapeutics. However, effective HDAC inhibitors for the treatment of solid tumors remain to be developed.Methodology\\/Principal FindingsHere, we propose a novel HDAC inhibitor, N-Hydroxy-4-(4-phenylbutyryl-amino) benzamide (HTPB), as a potential chemotherapeutic drug for solid tumors. The HDAC inhibition of HTPB was confirmed using HDAC activity assay. The antiproliferative and anti-migratory

Jiunn-Min Shieh; Tzu-Tang Wei; Yen-An Tang; Sin-Ming Huang; Wei-Ling Wen; Mei-Yu Chen; Hung-Chi Cheng; Santosh B. Salunke; Ching-Shih Chen; Pinpin Lin; Chien-Tien Chen; Yi-Ching Wang

2012-01-01

48

Characterisation of the in vitro activity of the depsipeptide histone deacetylase inhibitor spiruchostatin A  

Microsoft Academic Search

We recently completed the total synthesis of spiruchostatin A, a depsipeptide natural product with close structural similarities to FK228, a histone deacetylase (HDAC) inhibitor (HDI) currently being evaluated in clinical trials for cancer. Here we report a detailed characterisation of the in vitro activity of spiruchostatin A. Spiruchostatin A was a potent (sub-nM) inhibitor of class I HDAC activity in

Simon J. Crabb; Melanie Howell; Helen Rogers; Muhammad Ishfaq; Alexander Yurek-George; Krystle Carey; Becky M. Pickering; Phil East; Richard Mitter; Satoko Maeda; Peter W. M. Johnson; Paul Townsend; Kazuo Shin-ya; Minoru Yoshida; A. Ganesan; Graham Packham

2008-01-01

49

Estrogen regulates histone deacetylases to prevent cardiac hypertrophy  

PubMed Central

The development and progression of cardiac hypertrophy often leads to heart failure and death, and important modulators of hypertrophy include the histone deacetylase proteins (HDACs). Estrogen inhibits cardiac hypertrophy and progression in animal models and humans. We therefore investigated the influence of 17-?-estradiol on the production, localization, and functions of prohypertrophic (class I) and antihypertrophic (class II) HDACs in cultured neonatal rat cardiomyocytes. 17-?-Estradiol or estrogen receptor ? agonists dipropylnitrile and ?-LGND2 comparably suppressed angiotensin II–induced HDAC2 (class I) production, HDAC-activating phosphorylation, and the resulting prohypertrophic mRNA expression. In contrast, estrogenic compounds derepressed the opposite effects of angiotensin II on the same parameters for HDAC4 and 5 (class II), resulting in retention of these deacetylases in the nucleus to inhibit hypertrophic gene expression. Key aspects were confirmed in vivo from the hearts of wild-type but not estrogen receptor ? (ER?) gene–deleted mice administered angiotensin II and estrogenic compounds. Our results identify a novel dual regulation of cardiomyocyte HDACs, shown here for the antihypertrophic sex steroid acting at ER?. This mechanism potentially supports using ER? agonists as HDAC modulators to treat cardiac disease. PMID:24152730

Pedram, Ali; Razandi, Mahnaz; Narayanan, Ramesh; Dalton, James T.; McKinsey, Timothy A.; Levin, Ellis R.

2013-01-01

50

Histone deacetylase expression in white matter oligodendrocytes after stroke.  

PubMed

Histone deacetylases (HDACs) constitute a super-family of enzymes grouped into four major classes (Class I-IV) that deacetylate histone tails leading to chromatin condensation and gene repression. Whether stroke-induced oligodendrogenesis is related to the expression of individual HDACs in the oligodendrocyte lineage has not been investigated. We found that 2 days after stroke, oligodendrocyte progenitor cells (OPCs) and mature oligodendrocytes (OLGs) were substantially reduced in the peri-infarct corpus callosum, whereas at 7 days after stroke, a robust increase in OPCs and OLGs was observed. Ischemic brains isolated from rats sacrificed 7 days after stroke were used to test levels of individual members of Class I (1 and 2) and Class II (4 and 5) HDACs in white matter oligodendrocytes during stroke-induced oligodendrogenesis. Double immunohistochemistry analysis revealed that stroke substantially increased the number of NG2+OPCs with nuclear HDAC1 and HDAC2 immunoreactivity and cytoplasmic HDAC4 which were associated with augmentation of proliferating OPCs, as determined by BrdU and Ki67 double reactive cells after stroke. A decrease in HDAC1 and an increase in HDAC2 immunoreactivity were detected in mature adenomatous polyposis coli (APC) positive OLGs, which paralleled an increase in newly generated BrdU positive OLGs in the peri-infarct corpus callosum. Concurrently, stroke substantially decreased the acetylation levels of histones H3 and H4 in both OPCs and OLGs. Taken together, these findings demonstrate that stroke induces distinct profiles of Class I and Class II HDACs in white matter OPCs and OLGs, suggesting that the individual members of Class I and II HDACs play divergent roles in the regulation of OPC proliferation and differentiation during brain repair after stroke. PMID:24657831

Kassis, Haifa; Chopp, Michael; Liu, Xian Shuang; Shehadah, Amjad; Roberts, Cynthia; Zhang, Zheng Gang

2014-11-01

51

Disruption of HDAC4/N-CoR complex by histone deacetylase inhibitors leads to inhibition of IL-2 gene expression.  

PubMed

Previous studies have shown that HDAC inhibitors selectively inhibit IL-2 gene expression, but the mechanism of this inhibition remains to be elucidated. It was recently reported that HDAC4, a component of the nuclear hormone receptor corepressor (N-CoR) complex, associates with the IL-2 promoter via the transcription factor myocyte enhancer factor 2 (MEF2). We therefore focused on the role of HDAC4/N-CoR complex in the transcriptional regulation of IL-2. Four approaches were used to characterize this role and to investigate the relation between the regulatory function of HDAC4/N-CoR complex and HDAC4-enzymatic activity: (i) HDAC4 silencing by RNA interference, (ii) overexpression of N-CoR repression domain 3 (RD3), (iii) overexpression of HDAC4 point mutants, and (iv) treatment with HDAC inhibitors. Here, we report that HDAC4 plays an essential role in IL-2 promoter activation, and that the formation of the HDAC4/N-CoR complex, which is closely related to HDAC4-enzymatic activity, might be involved in HDAC inhibitor-mediated inhibition of IL-2 gene expression. These observations indicate that the selective inhibition of HDAC4 or the interaction of HDAC4 with N-CoR is likely a potential target for the development of novel immunosuppressants. PMID:17559812

Matsuoka, Hideaki; Fujimura, Takao; Hayashi, Masako; Matsuda, Kaori; Ishii, Yoshinori; Aramori, Ichiro; Mutoh, Seitaro

2007-08-01

52

Histone Deacetylases in Skeletal Development and Bone Mass Maintenance  

PubMed Central

The skeleton is a multifunctional and regenerative organ. Dynamic activities within the bone microenvironment necessitate and instigate rapid and temporal changes in gene expression within the cells (osteoclasts, osteoblasts, and osteocytes) responsible for skeletal maintenance. Regulation of gene expression is controlled, in part, by histone deacetylases (Hdacs), which are intracellular enzymes that directly affect chromatin structure and transcription factor activity. Key roles for several Hdacs in bone development and biology have been elucidated though in vitro and in vivo models. Recent findings suggest that clinical usage of small molecule Hdac inhibitors for conditions like epilepsy, bipolar disorder, cancer, and a multitude of other ailments may have unintended effects on bone cell populations. Here we review the progress that has been made in the last decade in understanding how Hdacs contribute to bone development and maintenance. PMID:21185361

McGee-Lawrence, Meghan E.; Westendorf, Jennifer J.

2011-01-01

53

An unbiased approach to identify endogenous substrates of "histone" deacetylase 8.  

PubMed

Despite being extensively characterized structurally and biochemically, the functional role of histone deacetylase 8 (HDAC8) has remained largely obscure due in part to a lack of known cellular substrates. Herein, we describe an unbiased approach using chemical tools in conjunction with sophisticated proteomics methods to identify novel non-histone nuclear substrates of HDAC8, including the tumor suppressor ARID1A. These newly discovered substrates of HDAC8 are involved in diverse biological processes including mitosis, transcription, chromatin remodeling, and RNA splicing and may help guide therapeutic strategies that target the function of HDAC8. PMID:25089360

Olson, David E; Udeshi, Namrata D; Wolfson, Noah A; Pitcairn, Carol Ann; Sullivan, Eric D; Jaffe, Jacob D; Svinkina, Tanya; Natoli, Ted; Lu, Xiaodong; Paulk, Joshiawa; McCarren, Patrick; Wagner, Florence F; Barker, Doug; Howe, Eleanor; Lazzaro, Fanny; Gale, Jennifer P; Zhang, Yan-Ling; Subramanian, Aravind; Fierke, Carol A; Carr, Steven A; Holson, Edward B

2014-10-17

54

The Therapeutic Potential of Class I Selective Histone Deacetylase Inhibitors in Ovarian Cancer  

PubMed Central

Epithelial ovarian cancer remains the deadliest gynecologic malignancy. Despite advances in treatment, new approaches are needed. Histone deacetylases (HDACs) are a family of enzymes that regulate gene expression by removing acetyl groups from lysine residues on histones and non-histone proteins. Inhibition of HDACs with small molecules has led to the development of histone deacetylase inhibitors (HDACi) that are in clinical use, primarily for hematologic malignancies. Although clinical trials with HDACi as single agents in solid tumors have been disappointing, data from independent labs and recent work by our group show that class I selective HDACi have potent anti-tumor effects in pre-clinical models of ovarian cancer. This review summarizes the role of HDACs in ovarian cancer and the potential niche for selective class I HDACi, particularly HDAC3 in ovarian cancer therapy. PMID:24904826

Khabele, Dineo

2014-01-01

55

Histone deacetylase 10 promotes autophagy-mediated cell survival  

PubMed Central

Tumor cells activate autophagy in response to chemotherapy-induced DNA damage as a survival program to cope with metabolic stress. Here, we provide in vitro and in vivo evidence that histone deacetylase (HDAC)10 promotes autophagy-mediated survival in neuroblastoma cells. We show that both knockdown and inhibition of HDAC10 effectively disrupted autophagy associated with sensitization to cytotoxic drug treatment in a panel of highly malignant V-MYC myelocytomatosis viral-related oncogene, neuroblastoma derived-amplified neuroblastoma cell lines, in contrast to nontransformed cells. HDAC10 depletion in neuroblastoma cells interrupted autophagic flux and induced accumulation of autophagosomes, lysosomes, and a prominent substrate of the autophagic degradation pathway, p62/sequestosome 1. Enforced HDAC10 expression protected neuroblastoma cells against doxorubicin treatment through interaction with heat shock protein 70 family proteins, causing their deacetylation. Conversely, heat shock protein 70/heat shock cognate 70 was acetylated in HDAC10-depleted cells. HDAC10 expression levels in high-risk neuroblastomas correlated with autophagy in gene-set analysis and predicted treatment success in patients with advanced stage 4 neuroblastomas. Our results demonstrate that HDAC10 protects cancer cells from cytotoxic agents by mediating autophagy and identify this HDAC isozyme as a druggable regulator of advanced-stage tumor cell survival. Moreover, these results propose a promising way to considerably improve treatment response in the neuroblastoma patient subgroup with the poorest outcome. PMID:23801752

Oehme, Ina; Linke, Jan-Peter; Bock, Barbara C.; Milde, Till; Lodrini, Marco; Hartenstein, Bettina; Wiegand, Inga; Eckert, Christian; Roth, Wilfried; Kool, Marcel; Kaden, Sylvia; Grone, Hermann-Josef; Schulte, Johannes H.; Lindner, Sven; Hamacher-Brady, Anne; Brady, Nathan R.; Deubzer, Hedwig E.; Witt, Olaf

2013-01-01

56

Metabolism as a key to histone deacetylase inhibition  

PubMed Central

There is growing interest in the epigenetic mechanisms that are dysregulated in cancer and other human pathologies. Under this broad umbrella, modulators of histone deacetylase (HDAC) activity have gained interest as both cancer chemopreventive and therapeutic agents. Of the first generation, FDA-approved HDAC inhibitors to have progressed to clinical trials, vorinostat represents a “direct acting” compound with structural features suitable for docking into the HDAC pocket, whereas romidepsin can be considered a prodrug that undergoes reductive metabolism to generate the active intermediate (a zinc-binding thiol). It is now evident that other agents, including those in the human diet, can be converted by metabolism to intermediates that affect HDAC activity. Examples are cited of short-chain fatty acids, seleno-?-keto acids, small molecule thiols, mercapturic acid metabolites, indoles, and polyphenols. The findings are discussed in the context of putative endogenous HDAC inhibitors generated by intermediary metabolism (e.g. pyruvate), the yin–yang of HDAC inhibition versus HDAC activation, and the screening assays that might be most appropriate for discovery of novel HDAC inhibitors in the future. PMID:21599534

Rajendran, Praveen; Williams, David E.; Ho, Emily; Dashwood, Roderick H.

2012-01-01

57

Selectively Targeting Prostate Cancer with Antiandrogen Equipped Histone Deacetylase Inhibitors  

PubMed Central

Diverse cellular processes relevant to cancer progression are regulated by the acetylation status of proteins. Among such processes is chromatin remodeling via histone proteins, controlled by opposing histone deacetylase (HDAC) and histone acetyltransferase (HAT) enzymes. Histone deacetylase inhibitors (HDACi) show great promise in preclinical cancer models, but clinical trials treating solid tumors have failed to improve patient survival. This is due in part to an inability of HDACi to effectively accumulate in cancerous cells. To address this problem we designed HDACi with secondary pharmacophores to facilitate selective accumulation in malignant cells. We present the first example of HDACi compounds targeted to prostate tumors by equipping them with the additional ability to bind the androgen receptor (AR) with non-steroidal antiandrogen moieties. Leads among these new dual-acting molecules bind to the AR and halt AR transcriptional activity at lower concentrations than clinical antiandrogens. They inhibit key isoforms of HDAC with low nanomolar potency. Fluorescent microscopy reveals varying degrees of AR nuclear localization in response to these compounds that correlates with their HDAC activity. These biological properties translate into potent anticancer activity against hormone dependent (AR+) LNCaP and to a lesser extent against hormone independent (AR?) DU145 prostate cancer, while having greatly reduced toxicity in non-cancerous cells. This illustrates that engaging multiple biological targets with a single chemical probe can achieve both potent and cell-type selective responses. PMID:24004176

Gryder, Berkley E.; Akbashev, Michelle J.; Rood, Michael K.; Raftery, Eric D.; Meyers, Warren M.; Dillard, Paulette; Khan, Shafiq; Oyelere, Adegboyega K.

2013-01-01

58

A Role for Histone Deacetylases in the Cellular and Behavioral Mechanisms Underlying Learning and Memory  

ERIC Educational Resources Information Center

Histone deacetylases (HDACs) are a family of chromatin remodeling enzymes that restrict access of transcription factors to the DNA, thereby repressing gene expression. In contrast, histone acetyltransferases (HATs) relax the chromatin structure allowing for an active chromatin state and promoting gene transcription. Accumulating data have…

Mahgoub, Melissa; Monteggia, Lisa M.

2014-01-01

59

Histone deacetylases 1 and 2 maintain S-phase chromatin and DNA replication fork progression  

PubMed Central

Background Histone deacetylases (HDACs) play a critical role in the maintenance of genome stability. Class I HDACs, histone deacetylase 1 and 2 (Hdac1 and Hdac2) are recruited to the replication fork by virtue of their interactions with the replication machinery. However, functions for Hdac1 and Hdac2 (Hdacs1,2) in DNA replication are not fully understood. Results Using genetic knockdown systems and novel Hdacs1,2-selective inhibitors, we found that loss of Hdacs1,2 leads to a reduction in the replication fork velocity, and an increase in replication stress response culminating in DNA damage. These observed defects are due to a direct role for Hdacs1,2 in DNA replication, as transcription of genes involved in replication was not affected in the absence of Hdacs1,2. We found that loss of Hdacs1,2 functions increases histone acetylation (ac) on chromatin in S-phase cells and affects nascent chromatin structure, as evidenced by the altered sensitivity of newly synthesized DNA to nuclease digestion. Specifically, H4K16ac, a histone modification involved in chromatin decompaction, is increased on nascent chromatin upon abolishing Hdacs1,2 activities. It was previously shown that H4K16ac interferes with the functions of SMARCA5, an ATP-dependent ISWI family chromatin remodeler. We found SMARCA5 also associates with nascent DNA and loss of SMARCA5 decreases replication fork velocity similar to the loss or inhibition of Hdacs1,2. Conclusions Our studies reveal important roles for Hdacs1,2 in nascent chromatin structure maintenance and regulation of SMARCA5 chromatin-remodeler function, which together are required for proper replication fork progression and genome stability in S-phase. PMID:23947532

2013-01-01

60

Alcohol-induced serotonergic modulation: the role of histone deacetylases.  

PubMed

Previous studies have demonstrated that alcohol use disorders (AUDs) are regulated by multiple mechanisms such as neurotransmitters and enzymes. The neurotransmitter, serotonin (5-hydroxytryptamine, 5-HT) may contribute to alcohol effects and serotonin receptors, including 5-HT3, play an important role in AUDs. Recent studies have also implicated histone deacetylases (HDACs) and acetyltransferases (HATS) in regulation of drug addiction, and HDAC inhibitors (HDACi) have been reported as transcriptional modulators of monoaminergic neurotransmission. Therefore, we hypothesize that HDACs may play a role in ethanol-induced serotonergic modulation. The effects of ethanol on serotonin and 5-HT3, and the role HDACs, HDAC activity and the HDACi, trichostatin A (TSA), play in alcohol-induced serotonergic effects were studied. Human SK-N-MC and neurons, were treated with ethanol (0.05, 0.1 and 0.2%), and/or TSA (50 nM), and 5-HT3 levels were assessed at 24-72 h. Gene expression was evaluated by qRT-PCR and protein by western blot and flow cytometry. Serotonin release was assessed by ELISA and HDAC activity by fluorometric assay. Our results show an increase in 5-HT3 gene after ethanol treatment. Further, ethanol significantly increased HDACs 1 and 3 genes accompanied by an increased in HDAC activity while TSA significantly inhibited HDACs. Studies with TSA show a significant upregulation of ethanol effects on 5-HT3, while surprisingly TSA inhibited ethanol-induced serotonin production. These results suggest that ethanol affects 5-HT3 and serotonin through mechanisms involving HDACs and HATs. In summary, our studies demonstrate some of the novel properties of HDAC inhibitors and contribute to the understanding of the mechanisms involve in alcohol-serotonergic modulation in the CNS. PMID:22796363

Agudelo, Marisela; Yoo, Changwon; Nair, Madhavan P

2012-11-01

61

Cloning, expression, and biochemical characterization of a new histone deacetylase-like protein from Thermus caldophilus GK24  

SciTech Connect

Histone deactylases (HDACs) are members of an ancient enzyme family found in eukaryotes as well as in prokaryotes such as archaebacteria and eubacteria. We here report a new histone deacetylase (Tca HDAC) that was cloned from the genomic library of Thermus caldophilus GK24 based on homology analysis with human histone deacetylase1 (HDAC1). The gene contains an open reading frame encoding 375 amino acids with a calculated molecular mass of 42,188 Da and the deduced amino acid sequence of Tca HDAC showed a 31% homology to human HDAC1. The Tca HDAC gene was over-expressed in Escherichia coli using a Glutathione-S transferase (GST) fusion vector (pGEX-4T-1) and the purified protein showed a deacetylase activity toward the fluorogenic substrate for HDAC. Moreover, the enzyme activity was inhibited by trichostatin A, a specific HDAC inhibitor, in a dose-dependent manner. Optimum temperature and pH of the enzyme was found to be approximately 70 {sup o}C and 7.0, respectively. In addition, zinc ion is required for catalytic activity of the enzyme. Together, these data demonstrate that Tca HDAC is a new histone deacetylase-like enzyme from T. caldophilus GK24 and will be a useful tool for deciphering the role of HDAC in the prokaryote and development of new biochemical reactions.

Song, Young Mi [Chemical Genomics Laboratory, Department of Biotechnology, College of Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, You Sun [Chemical Genomics Laboratory, Department of Biotechnology, College of Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Dooil [Korea Research Institute of Bioscience and Biotechnology, Daejon 305-600 (Korea, Republic of); Lee, Dae Sil [Korea Research Institute of Bioscience and Biotechnology, Daejon 305-600 (Korea, Republic of); Kwon, Ho Jeong [Chemical Genomics Laboratory, Department of Biotechnology, College of Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)]. E-mail: kwonhj@yonsei.ac.kr

2007-09-14

62

Ex Vivo Response to Histone Deacetylase (HDAC) Inhibitors of the HIV Long Terminal Repeat (LTR) Derived from HIV-Infected Patients on Antiretroviral Therapy  

PubMed Central

Histone deacetylase inhibitors (HDACi) can induce human immunodeficiency virus (HIV) transcription from the HIV long terminal repeat (LTR). However, ex vivo and in vivo responses to HDACi are variable and the activity of HDACi in cells other than T-cells have not been well characterised. Here, we developed a novel assay to determine the activity of HDACi on patient-derived HIV LTRs in different cell types. HIV LTRs from integrated virus were amplified using triple-nested Alu-PCR from total memory CD4+ T-cells (CD45RO+) isolated from HIV-infected patients prior to and following suppressive antiretroviral therapy. NL4-3 or patient-derived HIV LTRs were cloned into the chromatin forming episomal vector pCEP4, and the effect of HDACi investigated in the astrocyte and epithelial cell lines SVG and HeLa, respectively. There were no significant differences in the sequence of the HIV LTRs isolated from CD4+ T-cells prior to and after 18 months of combination antiretroviral therapy (cART). We found that in both cell lines, the HDACi panobinostat, trichostatin A, vorinostat and entinostat activated patient-derived HIV LTRs to similar levels seen with NL4-3 and all patient derived isolates had similar sensitivity to maximum HDACi stimulation. We observed a marked difference in the maximum fold induction of luciferase by HDACi in HeLa and SVG, suggesting that the effect of HDACi may be influenced by the cellular environment. Finally, we observed significant synergy in activation of the LTR with vorinostat and the viral protein Tat. Together, our results suggest that the LTR sequence of integrated virus is not a major determinant of a functional response to an HDACi. PMID:25409334

Lu, Hao K.; Gray, Lachlan R.; Wightman, Fiona; Ellenberg, Paula; Khoury, Gabriela; Cheng, Wan-Jung; Mota, Talia M.; Wesselingh, Steve; Gorry, Paul R.; Cameron, Paul U.

2014-01-01

63

Histone Acetylation and CREB Binding Protein Are Required for Neuronal Resistance against Ischemic Injury  

E-print Network

Epigenetic transcriptional regulation by histone acetylation depends on the balance between histone acetyltransferase (HAT) and deacetylase activities (HDAC). Inhibition of HDAC activity provides neuroprotection, indicating ...

Yildirim, Ferah

64

Novel antiproliferative chimeric compounds with marked histone deacetylase inhibitory activity.  

PubMed

Given our interest in finding potential antitumor agents and in view of the multifactorial mechanistic nature of cancer, in the present work, taking advantage of the multifunctional ligands approach, new chimeric molecules were designed and synthesized by combining in single chemical entities structural features of SAHA, targeting histone deacetylases (HDACs), with substituted stilbene or terphenyl derivatives previously obtained by us and endowed with antiproliferative and pro-apoptotic activity. The new chimeric derivatives were characterized with respect to their cytotoxic activity and their effects on cell cycle progression on different tumor cell lines, as well as their HDACs inhibition. Among the other, trans -6 showed the most interesting biological profile, as it exhibited a strong pro-apoptotic activity in tumor cell lines in comparison with both of its parent compounds and a marked HDAC inhibition. PMID:25221651

Giacomini, Elisa; Nebbioso, Angela; Ciotta, Alfonso; Ianni, Cristina; Falchi, Federico; Roberti, Marinella; Tolomeo, Manlio; Grimaudo, Stefania; Cristina, Antonietta Di; Pipitone, Rosaria Maria; Altucci, Lucia; Recanatini, Maurizio

2014-09-11

65

Dysregulation of Histone Acetyltransferases and Deacetylases in Cardiovascular Diseases  

PubMed Central

Cardiovascular disease (CVD) remains a leading cause of mortality worldwide despite advances in its prevention and management. A comprehensive understanding of factors which contribute to CVD is required in order to develop more effective treatment options. Dysregulation of epigenetic posttranscriptional modifications of histones in chromatin is thought to be associated with the pathology of many disease models, including CVD. Histone acetyltransferases (HATs) and deacetylases (HDACs) are regulators of histone lysine acetylation. Recent studies have implicated a fundamental role of reversible protein acetylation in the regulation of CVDs such as hypertension, pulmonary hypertension, diabetic cardiomyopathy, coronary artery disease, arrhythmia, and heart failure. This reversible acetylation is governed by enzymes that HATs add or HDACs remove acetyl groups respectively. New evidence has revealed that histone acetylation regulators blunt cardiovascular and related disease states in certain cellular processes including myocyte hypertrophy, apoptosis, fibrosis, oxidative stress, and inflammation. The accumulating evidence of the detrimental role of histone acetylation in cardiac disease combined with the cardioprotective role of histone acetylation regulators suggests that the use of histone acetylation regulators may serve as a novel approach to treating the millions of patients afflicted by cardiac diseases worldwide. PMID:24693336

Wang, Yonggang; Miao, Xiao; Liu, Yucheng; Li, Fengsheng; Liu, Quan; Sun, Jian; Cai, Lu

2014-01-01

66

Remodeling Chromatin and Stress Resistance in the Central Nervous System: Histone Deacetylase Inhibitors as Novel and Broadly Effective Neuroprotective Agents  

Microsoft Academic Search

Acetylation and deacetylation of histone protein plays a critical role in regulating gene expression in a host of biological processes including cellular proliferation, development, and differentiation. Accordingly, aberrant acetylation and deacetylation resulting from the misregulation of histone acetyltransferases (HATs) and\\/or histone deacetylases (HDACs) has been linked to clinical disorders such as Rubinstein-Taybi syndrome, fragile X syndrome, leukemia, and various cancers.

Brett Langley; JoAnn M. Gensert; M. Flint Beal; Rajiv R. Ratan

2005-01-01

67

Requirement of a novel splicing variant of human histone deacetylase 6 for TGF-{beta}1-mediated gene activation  

SciTech Connect

Histone deacetylase 6 (HDAC6) belongs to the family of class IIb HDACs and predominantly deacetylates non-histone proteins in the cytoplasm via the C-terminal deacetylase domain of its two tandem deacetylase domains. HDAC6 modulates fundamental cellular processes via deacetylation of {alpha}-tubulin, cortactin, molecular chaperones, and other peptides. Our previous study indicates that HDAC6 mediates TGF-{beta}1-induced epithelial-mesenchymal transition (EMT) in A549 cells. In the current study, we identify a novel splicing variant of human HDAC6, hHDAC6p114. The hHDAC6p114 mRNA arises from incomplete splicing and encodes a truncated isoform of the hHDAC6p114 protein of 114 kDa when compared to the major isoform hHDAC6p131. The hHDAC6p114 protein lacks the first 152 amino acids from N-terminus in the hHDAC6p131 protein, which harbors a nuclear export signal peptide and 76 amino acids of the N-terminal deacetylase domain. hHDAC6p114 is intact in its deacetylase activity against {alpha}-tubulin. The expression hHDAC6p114 is elevated in a MCF-7 derivative that exhibits an EMT-like phenotype. Moreover, hHDAC6p114 is required for TGF-{beta}1-activated gene expression associated with EMT in A549 cells. Taken together, our results implicate that expression and function of hHDAC6p114 is differentially regulated when compared to hHDAC6p131.

Zhuang, Yan [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States); Nguyen, Hong T. [Graduate Program in Biomedical Sciences, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Graduate Program in Biomedical Sciences, Tulane School of Medicine, New Orleans, LA 70112 (United States); Lasky, Joseph A. [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States); Cao, Subing [Graduate Program in Biomedical Sciences, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Graduate Program in Biomedical Sciences, Tulane School of Medicine, New Orleans, LA 70112 (United States); Li, Cui [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States) [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States); Xiangya Hospital, Central South University, Hunan 41008 (China); Hu, Jiyao; Guo, Xinyue; Burow, Matthew E. [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States); Shan, Bin, E-mail: bshan@tulane.edu [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States)] [Department of Medicine, Tulane School of Medicine, New Orleans, LA 70112 (United States)

2010-02-19

68

Histone Deacetylases Associated with the mSin3 Corepressor Mediate Mad Transcriptional Repression  

Microsoft Academic Search

Transcriptional repression by Mad–Max heterodimers requires interaction of Mad with the corepressors mSin3A\\/B. Sin3p, the S. cerevisiae homolog of mSin3, functions in the same pathway as Rpd3p, a protein related to two recently identified mammalian histone deacetylases, HDAC1 and HDAC2. Here, we demonstrate that mSin3A and HDAC1\\/2 are associated in vivo. HDAC2 binding requires a conserved region of mSin3A capable

Carol D. Laherty; Wen-Ming Yang; Jian-Min Sun; James R. Davie; Edward Seto; Robert N. Eisenman

1997-01-01

69

Novel inhibitors of human histone deacetylases: design, synthesis and bioactivity of 3-alkenoylcoumarines.  

PubMed

Histone deacetylases (HDACs) are well-established, promising targets for anticancer therapy due to their critical role in cancer development. Accordingly, an increasing number of HDAC inhibitors displaying cytotoxic effects against cancer cells have been reported. Among them, a large panel of chemical structures was described including coumarin-containing molecules. In this study, we described synthesis and biological activity of new coumarin-based derivatives as HDAC inhibitors. Among eight derivatives, three compounds showed HDAC inhibitory activities and antitumor activities against leukemia cell lines without affecting the viability of peripheral blood mononuclear cells from healthy donors. PMID:25042254

Seidel, Carole; Schnekenburger, Michael; Zwergel, Clemens; Gaascht, François; Mai, Antonello; Dicato, Mario; Kirsch, Gilbert; Valente, Sergio; Diederich, Marc

2014-08-15

70

Dietary Inhibitors of Histone Deacetylases in Intestinal Immunity and Homeostasis  

PubMed Central

Intestinal epithelial cells (IECs) are integral players in homeostasis of immunity and host defense in the gut and are under influence of the intestinal microbiome. Microbial metabolites and dietary components, including short chain fatty acids (acetate, propionate, and butyrate, SCFAs), have an impact on the physiology of IECs at multiple levels, including the inhibition of deacetylases affecting chromatin remodeling and global changes in transcriptional activity. The number and diversity of butyrate-producing bacteria is subject to factors related to age, disease, and to diet. At physiological levels, SCFAs are inhibitors of histone deacetylases (HDACs) which may explain the transcriptional effects of SCFAs on epithelial cells, although many effects of SCFAs on colonic mucosa can be ascribed to mechanisms beyond HDAC inhibition. Interference with this type of post-translational modification has great potential in cancer and different inflammatory diseases, because HDAC inhibition has anti-proliferative and anti-inflammatory effects in vitro, and in in vivo models of intestinal inflammation. Hence, the influence of dietary modulators on HDAC activity in epithelia is likely to be an important determinant of its responses to inflammatory and microbial challenges. PMID:23914191

Schilderink, R.; Verseijden, C.; de Jonge, W. J.

2013-01-01

71

Molecular Modeling Study on Tunnel Behavior in Different Histone Deacetylase Isoforms  

PubMed Central

Histone deacetylases (HDACs) have emerged as effective therapeutic targets in the treatment of various diseases including cancers as these enzymes directly involved in the epigenetic regulation of genes. However the development of isoform-selective HDAC inhibitors has been a challenge till date since all HDAC enzymes possess conserved tunnel-like active site. In this study, using molecular dynamics simulation we have analyzed the behavior of tunnels present in HDAC8, 10, and 11 enzymes of class I, II, and IV, respectively. We have identified the equivalent tunnel forming amino acids in these three isoforms and found that they are very much conserved with subtle differences to be utilized in selective inhibitor development. One amino acid, methionine of HDAC8, among six tunnel forming residues is different in isoforms of other classes (glutamic acid (E) in HDAC10 and leucine (L) in HDAC 11) based on which mutations were introduced in HDAC11, the less studied HDAC isoform, to observe the effects of this change. The HDAC8-like (L268M) mutation in the tunnel forming residues has almost maintained the deep and narrow tunnel as present in HDAC8 whereas HDAC10-like (L268E) mutation has changed the tunnel wider and shallow as observed in HDAC10. These results explained the importance of the single change in the tunnel formation in different isoforms. The observations from this study can be utilized in the development of isoform-selective HDAC inhibitors. PMID:23209570

Thangapandian, Sundarapandian; John, Shalini; Lee, Yuno; Arulalapperumal, Venkatesh; Lee, Keun Woo

2012-01-01

72

Development of a histone deacetylase 6 inhibitor and its biological effects  

PubMed Central

Development of isoform-selective histone deacetylase (HDAC) inhibitors is important in elucidating the function of individual HDAC enzymes and their potential as therapeutic agents. Among the eleven zinc-dependent HDACs in humans, HDAC6 is structurally and functionally unique. Here, we show that a hydroxamic acid-based small-molecule N-hydroxy-4-(2-[(2-hydroxyethyl)(phenyl)amino]-2-oxoethyl)benzamide (HPOB) selectively inhibits HDAC6 catalytic activity in vivo and in vitro. HPOB causes growth inhibition of normal and transformed cells but does not induce cell death. HPOB enhances the effectiveness of DNA-damaging anticancer drugs in transformed cells but not normal cells. HPOB does not block the ubiquitin-binding activity of HDAC6. The HDAC6-selective inhibitor HPOB has therapeutic potential in combination therapy to enhance the potency of anticancer drugs. PMID:24023063

Lee, Ju-Hee; Mahendran, Adaickapillai; Yao, Yuanshan; Ngo, Lang; Venta-Perez, Gisela; Choy, Megan L.; Kim, Nathaniel; Ham, Won-Seok; Breslow, Ronald; Marks, Paul A.

2013-01-01

73

Evaluation of Histone Deacetylases as Drug Targets in Huntington's Disease models  

PubMed Central

The family of histone deacetylases (HDACs) has recently emerged as important drug targets for treatment of slow progressive neurodegenerative disorders, including Huntington’s disease (HD). Broad pharmaceutical inhibition of HDACs has shown neuroprotective effects in various HD models. Here we examined the susceptibility of HDAC targets for drug treatment in affected brain areas during HD progression. We observed increased HDAC1 and decreased HDAC4, 5 and 6 levels, correlating with disease progression, in cortices and striata of HD R6/2 mice. However, there were no significant changes in HDAC protein levels, assessed in an age-dependent manner, in HD knock-in CAG140 mice and we did not observe significant changes in HDAC1 levels in human HD brains. We further assessed acetylation levels of ?-tubulin, as a biomarker of HDAC6 activity, and found it unchanged in cortices from R6/2, knock-in, and human subjects at all disease stages. Inhibition of deacetylase activities was identical in cortical extracts from R6/2 and wild-type mice treated with a class II-selective HDAC inhibitor. Lastly, treatment with class I- and II-selective HDAC inhibitors showed similar responses in HD and wild-type rat striatal cells. In conclusion, our results show that class I and class II HDAC targets are present and accessible for chronic drug treatment during HD progression and provide impetus for therapeutic development of brain-permeable class- or isoform-selective inhibitors. PMID:20877454

Quinti, Luisa; Chopra, Vanita; Rotili, Dante; Valente, Sergio; Amore, Allison; Franci, Gianluigi; Meade, Sarah; Valenza, Marta; Altucci, Lucia; Maxwell, Michele M.; Cattaneo, Elena; Hersch, Steven; Mai, Antonello; Kazantsev, Aleksey

2010-01-01

74

Melatonin prevents neonatal dexamethasone induced programmed hypertension: Histone deacetylase inhibition.  

PubMed

Adulthood hypertension can be programmed by corticosteroid exposure in early life. Oxidative stress, epigenetic regulation by histone deacetylases (HDACs), and alterations of renin-angiotensin system (RAS) are involved in the developmental programming of hypertension. We examined whether melatonin prevented neonatal dexamethasone (DEX)-induced programmed hypertension and how melatonin prevented these processes. We also examined whether HDAC inhibition by trichostatin A (TSA, a HDAC inhibitor) had similar effects. Male offspring were assigned to 5 groups (n=6/group): control, DEX, melatonin, DEX+melatonin, and DEX+TSA. Male rat pups were injected i.p. with DEX on day 1 (0.5mg/kg BW), day 2 (0.3mg/kg BW), and day 3 (0.1mg/kg BW) after birth. Melatonin was administered in drinking water at the dose of 0.01% during the lactation period. The DEX+TSA group received DEX and 0.5mg/kg TSA subcutaneous injection once daily for 1 week. All rats were killed at 16 weeks of age. Neonatal DEX exposure induced hypertension in male offspring at 16 weeks of age, which melatonin prevented. Neonatal DEX exposure decreased gene expression related to apoptosis, nephrogenesis, RAS, and sodium transporters. Yet DEX treatment increased protein levels of HDAC-1, -2, and -3 in the kidney. Melatonin therapy preserved the decreases of gene expression and decreased HDACs. Similarly, HDAC inhibition prevented DEX-induced programmed hypertension. In conclusion, melatonin therapy exerts a long-term protection against neonatal DEX-induced programmed hypertension. Its beneficial effects include alterations of RAS components and inhibition of class I HDACs. Given that the similar protective effects of melatonin and TSA, melatonin might inhibit HDACs to epigenetic regulation of hypertension-related genes to prevent programmed hypertension. PMID:25090636

Wu, Ting-Hsin; Kuo, Hsuan-Chang; Lin, I-Chun; Chien, Shao-Ju; Huang, Li-Tung; Tain, You-Lin

2014-10-01

75

Inhibitors of histone deacetylases enhance neurotoxicity of DNA damage.  

PubMed

The nonselective inhibitors of class I/II histone deacetylases (HDACs) including trichostatin A and the clinically used suberoylanilide hydroxamic acid (SAHA, vorinostat) are neuroprotective in several models of neuronal injury. Here, we report that in cultured cortical neurons from newborn rats and in the cerebral cortex of whole neonate rats, these HDAC inhibitors exacerbated cytotoxicity of the DNA double-strand break (DSB)-inducing anticancer drug etoposide by enhancing apoptosis. Similar neurotoxic interactions were also observed in neurons that were treated with other DNA damaging drugs including cisplatin and camptothecin. In addition, in rat neonates, SAHA increased cortical neuron apoptosis that was induced by a single injection of the NMDA receptor antagonist dizocilpine (MK801). In etoposide-treated neurons, the nonselective HDAC inhibition resulted in more DSBs. It also potentiated etoposide-induced accumulation and phosphorylation of the pro-apoptotic transcription factor p53. Moreover, nonselective HDAC inhibition exacerbated neuronal apoptosis that was induced by the overexpressed p53. Importantly, such effects cannot be fully explained by inhibition of HDAC1, which is known to play a role in DSB repair and regulation of p53. The specific HDAC1 inhibitor MS275 only moderately enhanced etoposide-induced neuronal death. Although in etoposide-treated neurons MS275 increased DSBs, it did not affect activation of p53. Our findings suggest that besides HDAC1, there are other class I/II HDACs that participate in neuronal DNA damage response attenuating neurotoxic consequences of genotoxic insults to the developing brain. PMID:25063076

Vashishta, A; Hetman, M

2014-12-01

76

Parkin Ubiquitinates Tar-DNA Binding Protein-43 (TDP-43) and Promotes Its Cytosolic Accumulation via Interaction with Histone Deacetylase 6 (HDAC6)*  

PubMed Central

The importance of E3 ubiquitin ligases, involved in the degradation of misfolded proteins or promotion of protein-protein interaction, is increasingly recognized in neurodegeneration. TDP-43 is a predominantly nuclear protein, which regulates the transcription of thousands of genes and binds to mRNA of the E3 ubiquitin ligase Parkin to regulate its expression. Wild type and mutated TDP-43 are detected in ubiquitinated forms within the cytosol in several neurodegenerative diseases. We elucidated the mechanisms of TDP-43 interaction with Parkin using transgenic A315T mutant TDP-43 (TDP43-Tg) mice, lentiviral wild type TDP-43, and Parkin gene transfer rat models. TDP-43 expression increased Parkin mRNA and protein levels. Lentiviral TDP-43 increased the levels of nuclear and cytosolic protein, whereas Parkin co-expression mediated Lys-48 and Lys-63-linked ubiquitin to TDP-43 and led to cytosolic co-localization of Parkin with ubiquitinated TDP-43. Parkin and TDP-43 formed a multiprotein complex with HDAC6, perhaps to mediate TDP-43 translocation. In conclusion, Parkin ubiquitinates TDP-43 and facilitates its cytosolic accumulation through a multiprotein complex with HDAC6. PMID:23258539

Hebron, Michaeline L.; Lonskaya, Irina; Sharpe, Kaydee; Weerasinghe, Puwakdandawe P. K.; Algarzae, Norah K.; Shekoyan, Ashot R.; Moussa, Charbel E.-H.

2013-01-01

77

Systemic or Intrahippocampal Delivery of Histone Deacetylase Inhibitors Facilitates Fear Extinction  

E-print Network

Systemic or Intrahippocampal Delivery of Histone Deacetylase Inhibitors Facilitates Fear Extinction and hippocampus-dependent memory. Little is known about the effects of HDAC inhibitors on extinction, a learning-min) contextual extinction session causes context-evoked fear to decrease to levels observed

Wood, Marcelo A.

78

Identification of Histone Deacetylase 3 as a Biomarker for Tumor Recurrence Following Liver Transplantation in HBV-Associated Hepatocellular Carcinoma  

Microsoft Academic Search

BackgroundRecent studies have shown that high expression levels of class I histone deacetylases (HDACs) correlate with malignant phenotype and poor prognosis in some human tumors. However, the expression patterns and prognostic role of class I HDAC isoforms in hepatocellular carcinoma (HCC) remain unclear.Methodology\\/Principal FindingsThe expression patterns and clinical significance of class I HDAC isoforms were assessed by immunohistochemistry in a

Li-Ming Wu; Zhe Yang; Lin Zhou; Feng Zhang; Hai-Yang Xie; Xiao-Wen Feng; Jian Wu; Shu-Sen Zheng; Jörg Hoheisel

2010-01-01

79

Histone Deacetylase 1 and 3 Regulate the Mesodermal Lineage Commitment of Mouse Embryonic Stem Cells  

PubMed Central

The important role of histone acetylation alteration has become increasingly recognized in mesodermal lineage differentiation and development. However, the contribution of individual histone deacetylases (HDACs) to mesoderm specification remains poorly understood. In this report, we found that trichostatin A (TSA), an inhibitor of histone deacetylase (HDACi), could induce early differentiation of embryonic stem cells (ESCs) and promote mesodermal lineage differentiation. Further analysis showed that the expression levels of HDAC1 and 3 are decreased gradually during ESCs differentiation. Ectopic expression of HDAC1 or 3 significantly inhibited differentiation into the mesodermal lineage. By contrast, loss of either HDAC1 or 3 enhanced the mesodermal differentiation of ESCs. Additionally, we demonstrated that the activity of HDAC1 and 3 is indeed required for the regulation of mesoderm gene expression. Furthermore, HDAC1 and 3 were found to interact physically with the T-box transcription factor T/Bry, which is critical for mesodermal lineage commitment. These findings indicate a key mechanism for the specific role of HDAC1 and 3 in mammalian mesoderm specification. PMID:25412078

Lv, Weiying; Guo, Xudong; Wang, Guiying; Xu, Yanxin; Kang, Jiuhong

2014-01-01

80

gp-91 mediates histone deacetylase inhibition-induced cardioprotection  

PubMed Central

We have recently shown that the inhibition of histone deacetylases (HDAC) protects the heart against ischemia and reperfusion (I/R) injury. The mechanism by which HDAC inhibition induces cardioprotection remains unknown. We sought to investigate whether the genetic disruption of gp-91, a subunit of NADPH-oxidase, would mitigate cardioprotection of HDAC inhibition. Wild-type and gp-91?/? mice were treated with a potent inhibitor of HDACs, trichostatin A (TSA, 0.1mg/kg, i.p.). Twenty-four hours later, the perfused hearts were subjected to 30 min of ischemia and 30 min of reperfusion. HDAC inhibition in wild-type mice produced marked improvements in ventricular functional recovery and the reduction of infarct size. TSA-induced cardioprotection was eliminated with genetic deletion of gp91. Notably, Western blot and immunostaining displayed a significant increase in gp-91 in myocardium following HDAC inhibition, which resulted in a mildly subsequent increase in the production of reactive oxygen species (ROS). The pretreatment of H9c2 cardiomyoblasts with TSA (50 nmol/L) decreased cell necrosis and increased viability in response to simulated ischemia (SI), which was abrogated by the transfection of cells with gp-91 siRNA, but not by scrambled siRNA. Furthermore, treatment of PLB-985 gp91+/+cells with TSA increased the resistance to SI, which also diminished with genetic disruption of gp91 in gp91phox-deficient PLB-985 cells. TSA treatment inhibited the increased active caspase-3 in H9c2 cardiomyoblasts and PLB-985 gp91+/+cells exposed to SI, which were prevented by knockdown of gp-91 by siRNA. These results suggest that a cascade consisting of gp-91 and HDAC inhibition plays an essential role in orchestrating the cardioprotective effect. PMID:20433879

Zhao, Ting C; Zhang, Ling X; Cheng, Guangmao; Liu, Jun T

2010-01-01

81

Design and synthesis of mono and bicyclic tetrapeptides thioester as potent inhibitor of histone deacetylases.  

PubMed

Inhibitors of histone deacetylases (HDACs) are a promising class of anticancer agents that have an effect on gene regulation. The naturally occurring cyclic depsipeptide FK228 containing disulfide and Largazole possessing thioester functionalities act as pro-drugs and share the same HDAC inhibition mechanism in cell. Inspired from these facts, we have reported bicyclic tetrapeptide disulfide HDAC inhibitors resembling FK228 with potent activity and enhanced selectivity. In the present study, we report the design and synthesis of several mono and bicyclic tetrapeptide thioester HDAC inhibitors that share the inhibition mechanism similar to Largazole. Most of the compounds showed HDAC1 and HDAC4 inhibition and p21 promoting activity in nanomolar ranges. Among these the monocyclic peptides 1, 2 and bicyclic peptide, 4 are notable demanding more advanced research to be promising anticancer drug candidates. PMID:25048030

Hoque, Md Ashraful; Islam, Md Shahidul; Islam, Md Nurul; Kato, Tamaki; Nishino, Norikazu; Ito, Akihiro; Yoshida, Minoru

2014-10-01

82

Genomic targets, and histone acetylation and gene expression profiling of neural HDAC inhibition  

PubMed Central

Histone deacetylase inhibitors (HDACis) have been shown to potentiate hippocampal-dependent memory and synaptic plasticity and to ameliorate cognitive deficits and degeneration in animal models for different neuropsychiatric conditions. However, the impact of these drugs on hippocampal histone acetylation and gene expression profiles at the genomic level, and the molecular mechanisms that underlie their specificity and beneficial effects in neural tissue, remains obscure. Here, we mapped four relevant histone marks (H3K4me3, AcH3K9,14, AcH4K12 and pan-AcH2B) in hippocampal chromatin and investigated at the whole-genome level the impact of HDAC inhibition on acetylation profiles and basal and activity-driven gene expression. HDAC inhibition caused a dramatic histone hyperacetylation that was largely restricted to active loci pre-marked with H3K4me3 and AcH3K9,14. In addition, the comparison of Chromatin immunoprecipitation sequencing and gene expression profiles indicated that Trichostatin A-induced histone hyperacetylation, like histone hypoacetylation induced by histone acetyltransferase deficiency, had a modest impact on hippocampal gene expression and did not affect the transient transcriptional response to novelty exposure. However, HDAC inhibition caused the rapid induction of a homeostatic gene program related to chromatin deacetylation. These results illuminate both the relationship between hippocampal gene expression and histone acetylation and the mechanism of action of these important neuropsychiatric drugs. PMID:23821663

Lopez-Atalaya, Jose P.; Ito, Satomi; Valor, Luis M.; Benito, Eva; Barco, Angel

2013-01-01

83

Histone deacetylase 8 regulates cortactin deacetylation and contraction in smooth muscle tissues.  

PubMed

Histone deacetylases (HDACs) are a family of enzymes that mediate nucleosomal histone deacetylation and gene expression. Some members of the HDAC family have also been implicated in nonhistone protein deacetylation, which modulates cell-cycle control, differentiation, and cell migration. However, the role of HDACs in smooth muscle contraction is largely unknown. Here, HDAC8 was localized both in the cytoplasm and the nucleus of mouse and human smooth muscle cells. Knockdown of HDAC8 by lentivirus-encoding HDAC8 shRNA inhibited force development in response to acetylcholine. Treatment of smooth muscle tissues with HDAC8 inhibitor XXIV (OSU-HDAC-44) induced relaxation of precontracted smooth muscle tissues. In addition, cortactin is an actin-regulatory protein that undergoes deacetylation during migration of NIH 3T3 cells. In this study, acetylcholine stimulation induced cortactin deacetylation in mouse and human smooth muscle tissues, as evidenced by immunoblot analysis using antibody against acetylated lysine. Knockdown of HDAC8 by RNAi or treatment with the inhibitor attenuated cortactin deacetylation and actin polymerization without affecting myosin activation. Furthermore, expression of a charge-neutralizing cortactin mutant inhibited contraction and actin dynamics during contractile activation. These results suggest a novel mechanism for the regulation of smooth muscle contraction. In response to contractile stimulation, HDAC8 may mediate cortactin deacetylation, which subsequently promotes actin filament polymerization and smooth muscle contraction. PMID:24920679

Li, Jia; Chen, Shu; Cleary, Rachel A; Wang, Ruping; Gannon, Olivia J; Seto, Edward; Tang, Dale D

2014-08-01

84

Boric acid inhibits embryonic histone deacetylases: A suggested mechanism to explain boric acid-related teratogenicity  

SciTech Connect

Histone deacetylases (HDAC) control gene expression by changing histonic as well as non histonic protein conformation. HDAC inhibitors (HDACi) are considered to be among the most promising drugs for epigenetic treatment for cancer. Recently a strict relationship between histone hyperacetylation in specific tissues of mouse embryos exposed to two HDACi (valproic acid and trichostatin A) and specific axial skeleton malformations has been demonstrated. The aim of this study is to verify if boric acid (BA), that induces in rodents malformations similar to those valproic acid and trichostatin A-related, acts through similar mechanisms: HDAC inhibition and histone hyperacetylation. Pregnant mice were treated intraperitoneally with a teratogenic dose of BA (1000 mg/kg, day 8 of gestation). Western blot analysis and immunostaining were performed with anti hyperacetylated histone 4 (H4) antibody on embryos explanted 1, 3 or 4 h after treatment and revealed H4 hyperacetylation at the level of somites. HDAC enzyme assay was performed on embryonic nuclear extracts. A significant HDAC inhibition activity (compatible with a mixed type partial inhibition mechanism) was evident with BA. Kinetic analyses indicate that BA modifies substrate affinity by a factor {alpha} = 0.51 and maximum velocity by a factor {beta} = 0.70. This work provides the first evidence for HDAC inhibition by BA and suggests such a molecular mechanism for the induction of BA-related malformations.

Di Renzo, Francesca [Department of Biology, University of Milan, Via Celoria, 26. 20133 Milan (Italy); Cappelletti, Graziella [Department of Biology, University of Milan, Via Celoria, 26. 20133 Milan (Italy); Broccia, Maria L. [Department of Biology, University of Milan, Via Celoria, 26. 20133 Milan (Italy); Giavini, Erminio [Department of Biology, University of Milan, Via Celoria, 26. 20133 Milan (Italy); Menegola, Elena [Department of Biology, University of Milan, Via Celoria, 26. 20133 Milan (Italy)]. E-mail: elena.menegola@unimi.it

2007-04-15

85

The antileishmanial activity of isoforms 6- and 8-selective histone deacetylase inhibitors.  

PubMed

Histone deacetylase inhibitors (HDACi) pleiotropy is largely due to their nonselective inhibition of various cellular HDAC isoforms. Connecting inhibition of a specific isoform to biological responses and/or phenotypes is essential toward deconvoluting HDACi pleiotropy. The contribution of classes I and II HDACs to the antileishmanial activity of HDACi was investigated using the amastigote and promastigote forms of Leishmania donovani. We observed that the antileishmanial activities of HDACi are largely due to the inhibition of HDAC6-like activity. This observation could facilitate the development of HDACi as antileishmanial agents. PMID:25240614

Sodji, Quaovi; Patil, Vishal; Jain, Surendra; Kornacki, James R; Mrksich, Milan; Tekwani, Babu L; Oyelere, Adegboyega K

2014-10-15

86

Synthesis and Biological Evaluation of the First Example of NO-Donor Histone Deacetylase Inhibitor  

PubMed Central

The NO-donor histone deacetylase inhibitor 2, formally obtained by joining Entinostat 1, a moderately selective Class I histone deacetylases (HDACs) inhibitor, to a 4-(methylaminomethyl)furoxan-3-carbonitrile scaffold, is described and its preliminary biological profile discussed. This hybrid regulates Classes I and II HDACs. Nitric oxide (NO) released by the compound activates soluble guanylate cyclase (sGC), causing Class II nuclear shuttling and chromatin modifications, with consequences on gene expression. The hybrid affects a number of micro-RNAs not modulated by its individual components; it promotes myogenic differentiation, inducing the formation of larger myotubes with significantly more nuclei per fiber, in a more efficient manner than the 1:1 mixture of its two components. The hybrid is an example of a new class of NO-donor HDACs now being developed, which should be of interest for treating a number of diseases. PMID:24900596

2013-01-01

87

Histone Deacetylase Inhibitors Sensitize Prostate Cancer Cells to Agents that Produce DNA Double-Strand Breaks by Targeting Ku70Acetylation  

Microsoft Academic Search

This study reports a histone deacetylation-independent mechanism whereby histone deacetylase (HDAC) inhibitors sensitize prostate cancer cells to DNA-damaging agents by targeting Ku70acetylation. Ku70represents a crucial compo- nent of the nonhomologous end joining repair machinery for DNA double-strand breaks (DSB). Our data indicate that pretreatment of prostate cancer cells with HDAC inhibitors (trichostatin A, suberoylanilide hydroxamic acid, MS-275, and OSU-HDAC42) led

Chang-Shi Chen; Yu-Chieh Wang; Hsiao-Ching Yang; Po-Hsien Huang; Samuel K. Kulp; Chih-Cheng Yang; Yen-Shen Lu; Shigemi Matsuyama; Ching-Yu Chen; Ching-Shih Chen

2007-01-01

88

Sequence-Dependent Radiosensitization of Histone Deacetylase Inhibitors Trichostatin A and SK-7041  

PubMed Central

Purpose This preclinical study is to determine whether the capacity of histone deacetylase (HDAC) inhibitors to enhance radiation response depends on temporal sequences of HDAC inhibition and irradiation. Materials and Methods The effects of HDAC inhibitors trichostatin A (TSA) and SK-7041 on radiosensitivity in human lung cancer cells were examined using a clonogenic assay, exposing cells to HDAC inhibitors in various sequences of HDAC inhibition and radiation. We performed Western blot of acetylated histone H3 and flow cytometry to analyze cell cycle phase distribution. Results TSA and SK-7041 augmented radiation cell lethality in an exposure time-dependent manner when delivered before irradiation. The impact of TSA and SK-7041 on radiosensitivity rapidly diminished when HDAC inhibition was delayed after irradiation. Radiation induced the acetylation of histone H3 in cells exposed to TSA, while irradiation alone had no effect on the expression of acetylated histone H3 in TSA-naïve cells. Preirradiation exposure to TSA abrogated radiation-induced G2/M-phase arrest. When delivered after irradiation, TSA had no effect on the peak of radiation-induced G2/M-phase arrest. Conclusion TSA and SK-7041 enhances radiosensitivity only when delivered before irradiation. Unless proven otherwise, it seems prudent to apply scheduling including preirradiation HDAC inhibition so that maximal radiosensitization is obtained. PMID:24454006

Kim, Jin Ho; Shin, Jin Hee; Kim, Hak Jae; Kim, In Ah

2013-01-01

89

Activation and Inhibition of Histone Deacetylase 8 by Monovalent Cations*  

PubMed Central

The metal-dependent histone deacetylases (HDACs) catalyze hydrolysis of acetyl groups from acetyllysine side chains and are targets of cancer therapeutics. Two bound monovalent cations (MVCs) of unknown function have been previously observed in crystal structures of HDAC8; site 1 is near the active site, whereas site 2 is located >20 ? from the catalytic metal ion. Here we demonstrate that one bound MVC activates catalytic activity (K1/2 = 3.4 mm for K+), whereas the second, weaker-binding MVC (K1/2 = 26 mm for K+) decreases catalytic activity by 11-fold. The weaker binding MVC also enhances the affinity of the HDAC inhibitor suberoylanilide hydroxamic acid by 5-fold. The site 1 MVC is coordinated by the side chain of Asp-176 that also forms a hydrogen bond with His-142, one of two histidines important for catalytic activity. The D176A and H142A mutants each increase the K1/2 for potassium inhibition by ?40-fold, demonstrating that the inhibitory cation binds to site 1. Furthermore, the MVC inhibition is mediated by His-142, suggesting that this residue is protonated for maximal HDAC8 activity. Therefore, His-142 functions either as an electrostatic catalyst or a general acid. The activating MVC binds in the distal site and causes a time-dependent increase in activity, suggesting that the site 2 MVC stabilizes an active conformation of the enzyme. Sodium binds more weakly to both sites and activates HDAC8 to a lesser extent than potassium. Therefore, it is likely that potassium is the predominant MVC bound to HDAC8 in vivo. PMID:20029090

Gantt, Stephanie L.; Joseph, Caleb G.; Fierke, Carol A.

2010-01-01

90

A new role for histone deacetylase 5 in the maintenance of long telomeres.  

PubMed

Telomeres are major regulators of genome stability and cell proliferation. A detailed understanding of the mechanisms involved in their maintenance is of foremost importance. Of those, telomere chromatin remodeling is probably the least studied; thus, we intended to explore the role of a specific histone deacetylase on telomere maintenance. We uncovered a new role for histone deacetylase 5 (HDAC5) in telomere biology. We report that HDAC5 is recruited to the long telomeres of osteosarcoma- and fibrosarcoma-derived cell lines, where it ensures proper maintenance of these repetitive regions. Indeed, depletion of HDAC5 by RNAi resulted in the shortening of longer telomeres and homogenization of telomere length in cells that use either telomerase or an alternative mechanism of telomere maintenance. Furthermore, we present evidence for the activation of telomere recombination on depletion of HDAC5 in fibrosarcoma telomerase-positive cancer cells. Of potential importance, we also found that depletion of HDAC5 sensitizes cancer cells with long telomeres to chemotherapeutic drugs. Cells with shorter telomeres were used to control the specificity of HDAC5 role in the maintenance of long telomeres. HDAC5 is essential for the length maintenance of long telomeres and its depletion is required for sensitization of cancer cells with long telomeres to chemotherapy. PMID:23729589

Novo, Clara Lopes; Polese, Catherine; Matheus, Nicolas; Decottignies, Anabelle; Londono-Vallejo, Arturo; Castronovo, Vincent; Mottet, Denis

2013-09-01

91

Histone deacetylase 3 is required for maintenance of bone mass during aging  

PubMed Central

Histone deacetylase 3 (Hdac3) is a nuclear enzyme that removes acetyl groups from lysine residues in histones and other proteins to epigenetically regulate gene expression. Hdac3 interacts with bone-related transcription factors and co-factors such as Runx2 and Zfp521, and thus is poised to play a key role in the skeletal system. To understand the role of Hdac3 in osteoblasts and osteocytes, Hdac3 conditional knockout (CKO) mice were created with the Osteocalcin (OCN) promoter driving Cre expression. Hdac3 CKOOCN mice were of normal size and weight, but progressively lost trabecular and cortical bone mass with age. The Hdac3 CKOOCN mice exhibited reduced cortical bone mineralization and material properties and suffered frequent fractures. Bone resorption was lower, not higher, in the Hdac3 CKOOCN mice, suggesting that primary defects in osteoblasts caused the reduced bone mass. Indeed, reductions in bone formation were observed. Osteoblasts and osteocytes from Hdac3 CKOOCN mice showed increased DNA damage and reduced functional activity in vivo and in vitro. Thus, Hdac3 expression in osteoblasts and osteocytes is essential for bone maintenance during aging. PMID:23085085

McGee-Lawrence, Meghan E.; Bradley, Elizabeth W.; Dudakovic, Amel; Carlson, Samuel W.; Ryan, Zachary C.; Kumar, Rajiv; Dadsetan, Mahrokh; Yaszemski, Michael J.; Chen, Qingshan; An, Kai-Nan; Westendorf, Jennifer J.

2012-01-01

92

Toward isozyme-selective inhibitors of histone deacetylase as therapeutic agents for the treatment of cancer  

PubMed Central

Since post-translational modifications of proteins are key mechanisms for controlling cellular function, targeting the machinery involved in these modifications offers new opportunities for the development of therapeutic agents. The histone deacetylases (HDACs) represent an important family of enzymes that are involved in controlling the acetylation state of key lysine residues in histones and other proteins. The development of HDAC inhibitors for the treatment of several diseases, most notably cancer, has proceeded rapidly. Recent attention has turned towards the development of isozyme-specific inhibitors that will provide selective targeting. It is believed that the ability to target-specific HDACs rather than all family members will lead to superior therapeutics with better efficacy and lower toxicity. A review of recent patents shows that researchers are targeting a wide range of isozymes and that key advances in the structural biology of HDACs are providing important design information. PMID:24163736

Ononye, Sophia N; van Heyst, Michael; Falcone, Eric M; Anderson, Amy C; Wright, Dennis L

2013-01-01

93

Global Histone H4 Acetylation and HDAC2 Expression in Colon Adenoma and Carcinoma  

PubMed Central

Chromatin remodeling and activation of transcription are important aspects of gene regulation, but these often go awry in disease progression, including during colon cancer development. We investigated the status of global histone acetylation (by measuring H3, H4 acetylation of lysine residues, which also occur over large regions of chromatin including coding regions and non-promoter sequences) and expression of histone deacetylase 2 (HDAC2) in colorectal cancer (CRC) tissue microarrays using immunohistochemical staining. Specifically, HDAC2 and the acetylation of histones H4K12 and H3K18 were evaluated in 134 colonic adenomas, 55 moderate to well differentiated carcinomas, and 4 poorly differentiated carcinomas compared to matched normal tissue. In addition, the correlation between expression of these epigenetic biomarkers and various clinicopathological factors including, age, location, and stage of the disease were analyzed. HDAC2 nuclear expression was detected at high levels in 81.9%, 62.1%, and 53.1% of CRC, adenomas, and normal tissue, respectively (P = 0.002). The corresponding nuclear global expression levels in moderate to well differentiated tumors for H4K12 and H3K18 acetylation were increased while these levels were decreased in poorly differentiated tumors (P = 0.02). HDAC2 expression was correlated significantly with progression of adenoma to carcinoma (P = 0.002), with a discriminative power of 0.74, when comparing cancer and non-cancer cases. These results suggest HDAC2 expression is significantly associated with CRC progression. PMID:19057998

Ashktorab, Hassan; Belgrave, Kevin; Hosseinkhah, Fatemeh; Brim, Hassan; Nouraie, Mehdi; Takkikto, Mikiko; Hewitt, Steve; Lee, Edward L.; Dashwood, R. H.; Smoot, Duane

2009-01-01

94

4-Phenylbutyric acid protects against neuronal cell death by primarily acting as a chemical chaperone rather than histone deacetylase inhibitor.  

PubMed

This letter describes the mechanism behind the protective effect of 4-phenylbutyric acid (4-PBA) against endoplasmic reticulum (ER) stress-induced neuronal cell death using three simple 4-(p-substituted phenyl) butyric acids (4-PBA derivatives). Their relative human histone deacetylase (HDAC) inhibitory activities were consistent with a structural model of their binding to HDAC7, and their ability to suppress neuronal cell death and activity of chemical chaperone in vitro. These data suggest that 4-PBA protects against neuronal cell death mediated by the chemical chaperone activity rather than by inhibition of histone deacetylase. PMID:24044874

Mimori, Seisuke; Ohtaka, Hiroyasu; Koshikawa, Yukari; Kawada, Koichi; Kaneko, Masayuki; Okuma, Yasunobu; Nomura, Yasuyuki; Murakami, Yasuoki; Hamana, Hiroshi

2013-11-01

95

Specific targeting and constitutive association of histone deacetylase complexes during transcriptional repression.  

PubMed

Specific recruitment of corepressor complexes containing histone deacetylases (HDAC) by transcription factors is believed to play an essential role in transcriptional repression. Recent studies indicate that repression by unliganded nuclear hormone receptors and by the Mad family of repressors requires distinct HDAC-containing corepressor complexes. In this work, we show that unliganded TR specifically recruits only the closely related N-CoR and SMRT-HDAC3 complexes, whereas the Mad1 recruits only the Sin3-HDAC1/2 complex. Significantly, both the Sin3 and Mi-2/NURD complexes also exhibit constitutive association with chromatin and contribute to chromatin deacetylation in a nontargeted fashion. These results suggest that HDAC complexes can contribute to gene repression by two distinct mechanisms as follows: (1) specific targeting by repressors and (2) constitutive association with chromatin. PMID:11914274

Li, Jiwen; Lin, Qiushi; Wang, Weidong; Wade, Paul; Wong, Jiemin

2002-03-15

96

Reduced Histone Deacetylase 7 Activity Restores Function to Misfolded CFTR in Cystic Fibrosis  

PubMed Central

Chemical modulation of histone deacetylase (HDAC) activity by HDAC inhibitors (HDACi) is an increasingly important approach to modify the etiology of human disease. Loss-of-function diseases arise as a consequence of protein misfolding and degradation leading to system failures. The ?F508 mutation in cystic fibrosis transmembrane conductance regulator (CFTR) results in the absence of the cell surface chloride channel and a loss of airway hydration, leading to premature lung failure and reduced lifespan responsible for cystic fibrosis (CF). We now show that the HDACi suberoylanilide hydroxamic acid (SAHA) restores surface channel activity in human primary airway epithelia to levels that are 28% of wild-type CFTR. Biological silencing of all known class I and II HDACs reveals that HDAC7 plays a central role in restoration of ?F508 function. We suggest that the tunable capacity of HDACs can be manipulated by chemical biology to counter the onset of CF and other human misfolding disorders. PMID:19966789

Hutt, Darren M.; Herman, David; Rodrigues, Ana P. C.; Noel, Sabrina; Pilewski, Joseph M.; Matteson, Jeanne; Hoch, Ben; Kellner, Wendy; Kelly, Jeffery W.; Schmidt, Andre; Thomas, Philip J.; Matsumura, Yoshihiro; Skach, William R.; Gentzsch, Martina; Riordan, John R.; Sorscher, Eric J.; Okiyoneda, Tsukasa; Lukacs, Gergely L.; Frizzell, Raymond A.; Manning, Gerard; Gottesfeld, Joel M.; Balch, William E.

2010-01-01

97

Histone deacetylase inhibitors: molecular mechanisms of action and clinical trials as anti-cancer drugs  

PubMed Central

Histone deacetylase (HDAC) inhibitors are a relatively new class of anti-cancer agents that play important roles in epigenetic or non-epigenetic regulation, inducing death, apoptosis, and cell cycle arrest in cancer cells. Recently, their use has been clinically validated in cancer patients resulting in the approval of two HDAC inhibitors, vorinostat and depsipetide, by the FDA. Also, clinical trials of several HDAC inhibitors for use as anti-cancer drugs (alone or in combination with other anti-cancer therapeutics) are ongoing. However, the molecular mechanisms underlying the response to HDAC inhibitors in cancer patients are not fully understood. In this review, we summarize our understanding of the molecular and biological events that underpin the anticancer effects of HDAC inhibitors and the outcomes of recent clinical trials involving these drugs. PMID:21416059

Kim, Hyun-Jung; Bae, Suk-Chul

2011-01-01

98

Epigenetic Regulation of Vascular Smooth Muscle Cell Proliferation and Neointima Formation by Histone Deacetylase Inhibition  

PubMed Central

Objective Proliferation of smooth muscle cells (SMC) in response to vascular injury is central to neointimal vascular remodeling. There is accumulating evidence that histone acetylation constitutes a major epigenetic modification for the transcriptional control of proliferative gene expression; however, the physiological role of histone acetylation for proliferative vascular disease remains elusive. Methods and Results In the present study, we investigated the role of histone deacetylase (HDAC) inhibition in SMC proliferation and neointimal remodeling. We demonstrate that mitogens induce transcription of HDAC 1, 2 and 3 in SMC. siRNA-mediated knock-down of either HDAC 1, 2 or 3 and pharmacologic inhibition of HDAC prevented mitogen-induced SMC proliferation. The mechanisms underlying this reduction of SMC proliferation by HDAC inhibition involve a growth arrest in the G1-phase of the cell cycle due to an inhibition of retinoblastoma protein phosphorylation. HDAC inhibition resulted in a transcriptional and posttranscriptional regulation of the cyclin-dependent kinase inhibitors p21Cip1 and p27Kip. Furthermore, HDAC inhibition repressed mitogen-induced cyclin D1 mRNA expression and cyclin D1 promoter activity. As a result of this differential cell cycle-regulatory gene expression by HDAC inhibition, the retinoblastoma protein retains a transcriptional repression of its downstream target genes required for S phase entry. Finally, we provide evidence that these observations are applicable in vivo by demonstrating that HDAC inhibition decreased neointima formation and expression of cyclin D1 in a murine model of vascular injury. Conclusion These findings identify HDAC as a critical component of a transcriptional cascade regulating SMC proliferation and suggest that HDAC might play a pivotal role in the development of proliferative vascular diseases, including atherosclerosis and in-stent restenosis. PMID:21233448

Findeisen, Hannes M.; Gizard, Florence; Zhao, Yue; Qing, Hua; Heywood, Elizabeth B.; Jones, Karrie L.; Cohn, Dianne; Bruemmer, Dennis

2011-01-01

99

3,3'-Diindolylmethane, but not indole-3-carbinol, inhibits histone deacetylase activity in prostate cancer cells.  

PubMed

Increased consumption of cruciferous vegetables is associated with a reduced risk of developing prostate cancer. Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM) are phytochemicals derived from cruciferous vegetables that have shown promise in inhibiting prostate cancer in experimental models. Histone deacetylase (HDAC) inhibition is an emerging target for cancer prevention and therapy. We sought to examine the effects of I3C and DIM on HDACs in human prostate cancer cell lines: androgen insensitive PC-3 cells and androgen sensitive LNCaP cells. I3C modestly inhibited HDAC activity in LNCaP cells by 25% but no inhibition of HDAC activity was detected in PC-3 cells. In contrast, DIM significantly inhibited HDAC activity in both cell lines by as much as 66%. Decreases in HDAC activity correlated with increased expression of p21, a known target of HDAC inhibitors. DIM treatment caused a significant decrease in the expression of HDAC2 protein in both cancer cell lines but no significant change in the protein levels of HDAC1, HDAC3, HDAC4, HDAC6 or HDAC8 was detected. Taken together, these results show that inhibition of HDAC activity by DIM may contribute to the phytochemicals' anti-proliferative effects in the prostate. The ability of DIM to target aberrant epigenetic patterns, in addition to its effects on detoxification of carcinogens, may make it an effective chemopreventive agent by targeting multiple stages of prostate carcinogenesis. PMID:22800507

Beaver, Laura M; Yu, Tian-Wei; Sokolowski, Elizabeth I; Williams, David E; Dashwood, Roderick H; Ho, Emily

2012-09-15

100

3,3?-Diindolylmethane, but not indole-3-carbinol, inhibits histone deacetylase activity in prostate cancer cells  

SciTech Connect

Increased consumption of cruciferous vegetables is associated with a reduced risk of developing prostate cancer. Indole-3-carbinol (I3C) and 3,3?-diindolylmethane (DIM) are phytochemicals derived from cruciferous vegetables that have shown promise in inhibiting prostate cancer in experimental models. Histone deacetylase (HDAC) inhibition is an emerging target for cancer prevention and therapy. We sought to examine the effects of I3C and DIM on HDACs in human prostate cancer cell lines: androgen insensitive PC-3 cells and androgen sensitive LNCaP cells. I3C modestly inhibited HDAC activity in LNCaP cells by 25% but no inhibition of HDAC activity was detected in PC-3 cells. In contrast, DIM significantly inhibited HDAC activity in both cell lines by as much as 66%. Decreases in HDAC activity correlated with increased expression of p21, a known target of HDAC inhibitors. DIM treatment caused a significant decrease in the expression of HDAC2 protein in both cancer cell lines but no significant change in the protein levels of HDAC1, HDAC3, HDAC4, HDAC6 or HDAC8 was detected. Taken together, these results show that inhibition of HDAC activity by DIM may contribute to the phytochemicals' anti-proliferative effects in the prostate. The ability of DIM to target aberrant epigenetic patterns, in addition to its effects on detoxification of carcinogens, may make it an effective chemopreventive agent by targeting multiple stages of prostate carcinogenesis. -- Highlights: ? DIM inhibits HDAC activity and decreases HDAC2 expression in prostate cancer cells. ? DIM is significantly more effective than I3C at inhibiting HDAC activity. ? I3C has no effect on HDAC protein expression. ? Inhibition of HDAC activity by DIM is associated with increased p21 expression. ? HDAC inhibition may be a novel epigenetic mechanism for cancer prevention with DIM.

Beaver, Laura M., E-mail: beaverl@onid.orst.edu [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States); School of Biological and Population Health Sciences, Oregon State University, 103 Milam Hall, Corvallis, OR 97331 (United States); Yu, Tian-Wei, E-mail: david.yu@oregonstate.edu [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States)] [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States); Sokolowski, Elizabeth I., E-mail: sokolowe@onid.orst.edu [School of Biological and Population Health Sciences, Oregon State University, 103 Milam Hall, Corvallis, OR 97331 (United States); Williams, David E., E-mail: david.williams@oregonstate.edu [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States); Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture and Life Sciences Building, Corvallis, OR 97331 (United States); Dashwood, Roderick H., E-mail: rod.dashwood@oregonstate.edu [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States); Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture and Life Sciences Building, Corvallis, OR 97331 (United States); Ho, Emily, E-mail: Emily.Ho@oregonstate.edu [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States) [Linus Pauling Institute, Oregon State University, 307 Linus Pauling Science Center, Corvallis, OR 97331 (United States); School of Biological and Population Health Sciences, Oregon State University, 103 Milam Hall, Corvallis, OR 97331 (United States)

2012-09-15

101

Residues in the 11 ? Channel of Histone Deacetylase 1 Promote Catalytic Activity  

PubMed Central

Histone deacetylase 1 (HDAC1) has been linked to cell growth and cell cycle regulation, which makes it a widely recognized target for anticancer drugs. Whereas variations of the metal-binding and capping groups of HDAC inhibitors have been studied extensively, the role of the linker region is less well known, despite the potency of inhibitors with diverse linkers, such as MS-275. To facilitate a drug design that targets HDAC1, we assessed the influence of residues in the 11 Å channel of the HDAC1 active site on activity by using an alanine scan. The mutation of eight channel residues to alanine resulted in a substantial reduction in deacetylase activity. Molecular dynamics simulations indicated that alanine mutation results in significant movement of the active-site channel, which suggests that channel residues promote HDAC1 activity by influencing substrate interactions. With little characterization of HDAC1 available, the combined experimental and computational results define the active-site residues of HDAC1 that are critical for substrate/inhibitor binding and provide important insight into drug design. PMID:18729444

Weerasinghe, Sujith V. W.; Estiu, Guillermina; Wiest, Olaf; Pflum, Mary Kay H.

2008-01-01

102

Histone Deacetylase 5 Is Not a p53 Target Gene, But Its Overexpression Inhibits Tumor Cell Growth and Induces Apoptosis  

Microsoft Academic Search

p53 tumor suppressor is activated by phosphorylation and acetylation on DNA damage. One of unknown p53 early transcripts was identified to be histone deacetylase-5 (HDAC5). We tested a hypothesis that HDAC5 is a p53 down-stream target gene that on induction by p53 inactivates p53 by removal of acetyl group in p53 molecule, thus functioning as an auto- regulatory negative feedback

Yuanhui Huang; Mingjia Tan; Mark Gosink; Kevin K. W. Wang; Yi Sun

2002-01-01

103

Silencing histone deacetylase-specific isoforms enhances expression of pluripotency genes in bovine fibroblasts.  

PubMed

Histone deacetylases (HDACs) catalyze deacetylation of histones that results in altered transcriptional activity. Inhibitors of HDACs have been shown to induce transcriptional changes that contribute positively to reprogramming somatic cells either by nuclear transfer or inducing a pluripotent state. However, the exact molecular mechanisms whereby HDAC inhibitors function and the specificity of the HDAC isoforms in cell reprogramming are not yet fully understood. Herein, we report the ability of individual isoform-specific HDACs to modulate endogenous expression of pluripotency-associated genes in bovine somatic cells. This in vitro study showed that a transient selective depletion of HDACs resulted in elevated mRNA levels of Oct-4, Sox2, and Nanog. In particular, we found that inhibition of specific HDAC isoforms using small interfering (si) RNA significantly increased expression of Nanog, a key factor required for totipotency induced by somatic cell nuclear transfer and for maintaining pluripotency in embryonic and induced pluripotent stem cells. Our study suggests that this gene might be the most susceptible to HDAC activity inhibition. Moreover, a regulatory role of the class III HDAC, SIRT3, on an Oct4-Sox2-Nanog transcriptional network was revealed. We observed the upregulation of pluripotency-related genes by depletion of SIRT3. SIRT3 is localized to mitochondria and is associated with energy metabolism processes, suggesting metabolic changes may be linked to reprogramming in bovine fibroblasts. In conclusion, we show that targeting selective HDACs can potentially be useful to enhance reprogramming and that sirtuins may play a pivotal role in somatic cell reprogramming by upregulating an Oct4-Sox2-Nanog transcriptional network. Dedifferentiating donor somatic cells by upregulating developmentally important genes through specific knockdown of epigenetic targets, in particular HDACs, may provide a path to improving livestock cloning and the in vitro production of pluripotent cells. PMID:24020699

Staszkiewicz, Jaroslaw; Power, Rachel A; Harkins, Lettie L; Barnes, Christian W; Strickler, Karen L; Rim, Jong S; Bondioli, Kenneth R; Eilersten, Kenneth J

2013-10-01

104

Roles of histone deacetylases in epigenetic regulation: emerging paradigms from studies with inhibitors.  

PubMed

The zinc-dependent mammalian histone deacetylase (HDAC) family comprises 11 enzymes, which have specific and critical functions in development and tissue homeostasis. Mounting evidence points to a link between misregulated HDAC activity and many oncologic and nononcologic diseases. Thus the development of HDAC inhibitors for therapeutic treatment garners a lot of interest from academic researchers and biotechnology entrepreneurs. Numerous studies of HDAC inhibitor specificities and molecular mechanisms of action are ongoing. In one of these studies, mass spectrometry was used to characterize the affinities and selectivities of HDAC inhibitors toward native HDAC multiprotein complexes in cell extracts. Such a novel approach reproduces in vivo molecular interactions more accurately than standard studies using purified proteins or protein domains as targets and could be very useful in the isolation of inhibitors with superior clinical efficacy and decreased toxicity compared to the ones presently tested or approved. HDAC inhibitor induced-transcriptional reprogramming, believed to contribute largely to their therapeutic benefits, is achieved through various and complex mechanisms not fully understood, including histone deacetylation, transcription factor or regulator (including HDAC1) deacetylation followed by chromatin remodeling and positive or negative outcome regarding transcription initiation. Although only a very low percentage of protein-coding genes are affected by the action of HDAC inhibitors, about 40% of noncoding microRNAs are upregulated or downregulated. Moreover, a whole new world of long noncoding RNAs is emerging, revealing a new class of potential targets for HDAC inhibition. HDAC inhibitors might also regulate transcription elongation and have been shown to impinge on alternative splicing. PMID:22414492

Delcuve, Geneviève P; Khan, Dilshad H; Davie, James R

2012-01-01

105

The role of redox modulation of class II histone deacetylases in mediating pathological cardiac hypertrophy  

Microsoft Academic Search

Many biological functions in cells are regulated by the effects of the redox state on cellular signaling pathways. In the\\u000a heart, pathological hypertrophy caused by a wide variety of stimuli is commonly mediated by nucleo-cytoplasmic translocation\\u000a of class II histone deacetylases (HDACs) and subsequent de-suppression of transcription factors, including nuclear factor\\u000a of activated T-cells and MEF2. One of the primary

Shin-ichi Oka; Tetsuro Ago; Takanari Kitazono; Daniela Zablocki; Junichi Sadoshima

2009-01-01

106

Immune regulation by histone deacetylases: a focus on the alteration of FOXP3 activity  

Microsoft Academic Search

Several histone deacetylases (HDACs) are involved in the regulation of forkhead box protein P3 (FOXP3) expression and function by affecting features of FOXP3 protein stability. FOXP3, a forkhead family transcription factor specially expressed in regulatory T (Treg) cells, controls the expression of many key immune-regulatory genes. Treg cells are a population of T lymphocytes that have critical roles in the

Hongtao Zhang; Yan Xiao; Zhiqiang Zhu; Bin Li; Mark I Greene

2012-01-01

107

Histone deacetylase inhibitors in glioblastoma: pre-clinical and clinical experience.  

PubMed

Epigenetic mechanisms are increasingly recognized as a major factor contributing to pathogenesis of cancer including glioblastoma, the most common and most malignant primary brain tumour in adults. Enzymatic modifications of histone proteins regulating gene expression are being exploited for therapeutic drug targeting. Over the last decade, numerous studies have shown promising results with histone deacetylase (HDAC) inhibitors in various malignancies. This article provides a brief overview of mechanism of anti-cancer effect and pharmacology of HDAC inhibitors and summarizes results from pre-clinical and clinical studies in glioblastoma. It analyses experience with HDAC inhibitors as single agents as well as in combination with targeted agents, cytotoxic chemotherapy and radiotherapy. Hallmark features of glioblastoma, such as uncontrolled cellular proliferation, invasion, angiogenesis and resistance to apoptosis, have been shown to be targeted by HDAC inhibitors in experiments with glioblastoma cell lines. Vorinostat is the most advanced HDAC inhibitor that entered clinical trials in glioblastoma, showing activity in recurrent disease. Multiple phase II trials with vorinostat in combination with targeted agents, temozolomide and radiotherapy are currently recruiting. While the results from pre-clinical studies are encouraging, early clinical trials showed only modest benefit and the value of HDAC inhibitors for clinical practice will need to be confirmed in larger prospective trials. Further research in epigenetic mechanisms driving glioblastoma pathogenesis and identification of molecular subtypes of glioblastoma is needed. This will hopefully lead to better selection of patients who will benefit from treatment with HDAC inhibitors. PMID:24838514

Bezecny, Pavel

2014-06-01

108

Kinetic method for the large-scale analysis of the binding mechanism of histone deacetylase inhibitors.  

PubMed

Performing kinetic studies on protein ligand interactions provides important information on complex formation and dissociation. Beside kinetic parameters such as association rates and residence times, kinetic experiments also reveal insights into reaction mechanisms. Exploiting intrinsic tryptophan fluorescence a parallelized high-throughput Förster resonance energy transfer (FRET)-based reporter displacement assay with very low protein consumption was developed to enable the large-scale kinetic characterization of the binding of ligands to recombinant human histone deacetylases (HDACs) and a bacterial histone deacetylase-like amidohydrolase (HDAH) from Bordetella/Alcaligenes. For the binding of trichostatin A (TSA), suberoylanilide hydroxamic acid (SAHA), and two other SAHA derivatives to HDAH, two different modes of action, simple one-step binding and a two-step mechanism comprising initial binding and induced fit, were verified. In contrast to HDAH, all compounds bound to human HDAC1, HDAC6, and HDAC8 through a two-step mechanism. A quantitative view on the inhibitor-HDAC systems revealed two types of interaction, fast binding and slow dissociation. We provide arguments for the thesis that the relationship between quantitative kinetic and mechanistic information and chemical structures of compounds will serve as a valuable tool for drug optimization. PMID:24882269

Meyners, Christian; Baud, Matthias G J; Fuchter, Matthew J; Meyer-Almes, Franz-Josef

2014-09-01

109

Role of histone deacetylase 2 in epigenetics and cellular senescence: implications in lung inflammaging and COPD  

PubMed Central

Histone deacetylase 2 (HDAC2) is a class I histone deacetylase that regulates various cellular processes, such as cell cycle, senescence, proliferation, differentiation, development, apoptosis, and glucocorticoid function in inhibiting inflammatory response. HDAC2 has been shown to protect against DNA damage response and cellular senescence/premature aging via an epigenetic mechanism in response to oxidative stress. These phenomena are observed in patients with chronic obstructive pulmonary disease (COPD). HDAC2 is posttranslationally modified by oxidative/carbonyl stress imposed by cigarette smoke and oxidants, leading to its reduction via an ubiquitination-proteasome dependent degradation in lungs of patients with COPD. In this perspective, we have discussed the role of HDAC2 posttranslational modifications and its role in regulation of inflammation, histone/DNA epigenetic modifications, DNA damage response, and cellular senescence, particularly in inflammaging, and during the development of COPD. We have also discussed the potential directions for future translational research avenues in modulating lung inflammaging and cellular senescence based on epigenetic chromatin modifications in diseases associated with increased oxidative stress. PMID:22842217

Yao, Hongwei

2012-01-01

110

Endogenous Modulators and Pharmacological Inhibitors of Histone Deacetylases in Cancer Therapy  

PubMed Central

The class I histone deacetylases HDAC1 and HDAC2 belong to a family of 11 zinc-dependent human HDACs and are overexpressed in many cancers. Inhibitors of these HDACs now in clinical trials show activity against several types of cancers. This review is focuse on recent advances in both clinical and preclinical efforts to understand the basis for HDACi actions, with an emphasis on implications for rational combinations with conventional or other targeted agents. We will address new perspectives on the molecular mechanisms by which HDACs act and how these actions relate to cancer. We will also review new evidence demonstrating that HDACs are direct intracellular targets of the potent sphingolipid mediator sphingosine-1-phosphate (S1P), the first identified endogenous nuclear regulator of these enzymes, linking sphingolipid metabolism in the nucleus to remodeling of chromatin and epigenetic regulation of gene expression. Understanding how endogenous molecules regulate HDAC activity in vivo may facilitate the search for safer and more effective anti-cancer drugs capable of interfering with HDAC functions in a highly specific manner. PMID:21725353

Spiegel, Sarah; Milstien, Sheldon; Grant, Steven

2012-01-01

111

Entinostat is a histone deacetylase inhibitor selective for class 1 histone deacetylases and activates HIV production from latently infected primary T cells  

PubMed Central

Objectives To compare the potency, toxicity and mechanism of action of multiple histone deacetylase inhibitors (HDACi) in activating HIV production from latency. Design In-vitro analysis of HDACi in a primary T-cell model of HIV latency and latently infected cell lines. Methods Latently infected chemokine ligand 19 (CCL19)-treated CD4+ T cells and the latently infected cell lines ACH2 and J-Lat were treated with a panel of HDACi, including entinostat, vorinostat, panonbinostat and MCT3. Viral production and cell viability were compared. Expression of cellular HDACs was measured by western blot and PCR. Association of HDACs with the HIV long-terminal repeat (LTR) using latently infected CCL19-treated primary CD4+ T cells in the presence and absence of specific HDACi was determined by chromatin immunoprecipitation (ChIP). Results We demonstrated considerable variation in the potency and toxicity of HDACi in latently infected primary CD4+ T cells and cell lines. All HDACi tested activated HIV production in latently infected primary T cells with greatest potency demonstrated with entinostat and vorinostat and greatest toxicity with panobinostat. Following the addition of HDACi in vitro, there were no changes in markers of T-cell activation or expression of the HIV coreceptors chemokine (C-X-C motif) receptor 4 (CXCR4) or chemokine (C-C motif) receptor type 5 (CCR5). ChIP analysis of latently infected CCL19-treated primary CD4+ T cells showed binding by HDAC1, HDAC2 and HDAC3 to the LTR with removal of HDAC1 and HDAC2 following treatment with the HDACi vorinostat and HDAC1 only following treatment with entinostat. Conclusion The HDACi entinostat, selective for inhibition of class I HDACs, induced virus expression in latently infected primary CD4+ T cells making this compound an attractive novel option for future clinical trials. PMID:24189584

Wightman, Fiona; Lu, Hao K.; Solomon, Ajantha E.; Saleh, Suha; Harman, Andrew N.; Cunningham, Anthony L.; Gray, Lachlan; Churchill, Melissa; Cameron, Paul U.; Dear, Anthony E.; Lewin, Sharon R.

2014-01-01

112

Inhibition of histone deacetylase in utero causes sociability deficits in postnatal mice.  

PubMed

Exposure to sodium valproate (VPA) in utero increases the risk of language impairment and a diagnosis of autism spectrum disorder (ASD). Mice exposed to VPA while in utero have also shown postnatal social deficits. Inhibition of histone deacetylase (HDAC) is one of VPA's many biological effects. The main objective of this study was to test the hypothesis that HDAC inhibition causes these behavioral outcomes following prenatal VPA exposure in mice. We exposed embryonic mice to VPA, the HDAC inhibitor trichostatin A (TSA), or vehicle controls. TSA (1mg/kg) inhibited HDAC in embryonic tissue at a level comparable to 600 mg/kg VPA, resulting in significant increases in histone H3 and H4 acetylation, and histone H3 lysine 4 tri-methylation. Postnatally, decreases in ultrasonic vocalization, olfactory motivation and sociability were observed in TSA and VPA-exposed pups. Treated mice exhibited elevated digging and grooming suggestive of mild restrictive and repetitive behaviors. Olfactory social preference, social novelty and habituation were normal. Together, these data indicate that embryonic HDAC inhibition alone can cause abnormal social behaviors in mice. This result serves as a molecular understanding of infant outcomes following mild VPA exposure in utero. PMID:24103642

Moldrich, Randal X; Leanage, Gayeshika; She, David; Dolan-Evans, Elliot; Nelson, Michael; Reza, Nargis; Reutens, David C

2013-11-15

113

A novel histone deacetylase pathway regulates mitosis by modulating Aurora B kinase activity  

PubMed Central

Histone deacetylase (HDAC) inhibitors perturb the cell cycle and have great potential as anti-cancer agents, but their mechanism of action is not well established. HDACs classically function as repressors of gene expression, tethered to sequence-specific transcription factors. Here we report that HDAC3 is a critical, transcription-independent regulator of mitosis. HDAC3 forms a complex with A-Kinase-Anchoring Proteins AKAP95 and HA95, which are targeted to mitotic chromosomes. Deacetylation of H3 in mitosis requires AKAP95/HA95 and HDAC3 and provides a hypoacetylated H3 tail that is the preferred substrate for Aurora B kinase. Phosphorylation of H3S10 by Aurora B leads to dissociation of HP1 proteins from methylated H3K9 residues on mitotic heterochromatin. This transcription-independent pathway, involving interdependent changes in histone modification and protein association, is required for normal progression through mitosis and is an unexpected target of HDAC inhibitors, a class of drugs currently in clinical trials for treating cancer. PMID:16980585

Li, Yun; Kao, Gary D.; Garcia, Benjamin A.; Shabanowitz, Jeffrey; Hunt, Donald F.; Qin, Jun; Phelan, Caroline; Lazar, Mitchell A.

2006-01-01

114

Histone deacetylase 8 is deregulated in urothelial cancer but not a target for efficient treatment  

PubMed Central

Background Previous studies have shown that class-I histone deacetylase (HDAC) 8 mRNA is upregulated in urothelial cancer tissues and urothelial cancer cell lines compared to benign controls. Using urothelial cancer cell lines we evaluated whether specific targeting of HDAC8 might be a therapeutic option in bladder cancer treatment. Methods We conducted siRNA-mediated knockdown and specific pharmacological inhibition of HDAC8 with the three different inhibitors compound 2, compound 5, and compound 6 in several urothelial carcinoma cell lines with distinct HDAC8 expression profiles. Levels of HDAC and marker proteins were determined by western blot analysis and mRNA levels were measured by quantitative real-time PCR. Cellular effects of HDAC8 suppression were analyzed by ATP assay, flow cytometry, colony forming assay and migration assay. Results Efficient siRNA-mediated knockdown of HDAC8 reduced proliferation up to 45%. The HDAC8 specific inhibitors compound 5 and compound 6 significantly reduced viability of all urothelial cancer cell lines (IC50 9 – 21 ?M). Flow cytometry revealed only a slight increase in the sub-G1 fraction indicating a limited induction of apoptosis. Expression of thymidylate synthase was partly reduced; PARP-cleavage was not detected. The influence of the pharmacological inhibition on clonogenic growth and migration show a cell line- and inhibitor-dependent reduction with the strongest effects after treatment with compound 5 and compound 6. Conclusions Deregulation of HDAC8 is frequent in urothelial cancer, but neither specific pharmacological inhibition nor siRNA-mediated knockdown of HDAC8 impaired viability of urothelial cancer cell lines in a therapeutic useful manner. Accordingly, HDAC8 on its own is not a promising drug target in bladder cancer. PMID:25011684

2014-01-01

115

Activation of p53 Transcriptional Activity by SMRT: a Histone Deacetylase 3-Independent Function of a Transcriptional Corepressor  

PubMed Central

The silencing mediator of retinoic acid and thyroid hormone receptors (SMRT) is an established histone deacetylase 3 (HDAC3)-dependent transcriptional corepressor. Microarray analyses of MCF-7 cells transfected with control or SMRT small interfering RNA revealed SMRT regulation of genes involved in DNA damage responses, and the levels of the DNA damage marker ?H2AX as well as poly(ADP-ribose) polymerase cleavage were elevated in SMRT-depleted cells treated with doxorubicin. A number of these genes are established p53 targets. SMRT knockdown decreased the activity of two p53-dependent reporter genes as well as the expression of p53 target genes, such as CDKN1A (which encodes p21). SMRT bound directly to p53 and was recruited to p53 binding sites within the p21 promoter. Depletion of GPS2 and TBL1, components of the SMRT corepressor complex, but not histone deacetylase 3 (HDAC3) decreased p21-luciferase activity. p53 bound to the SMRT deacetylase activation domain (DAD), which mediates HDAC3 binding and activation, and HDAC3 could attenuate p53 binding to the DAD region of SMRT. Moreover, an HDAC3 binding-deficient SMRT DAD mutant coactivated p53 transcriptional activity. Collectively, these data highlight a biological role for SMRT in mediating DNA damage responses and suggest a model where p53 binding to the DAD limits HDAC3 interaction with this coregulator, thereby facilitating SMRT coactivation of p53-dependent gene expression. PMID:24449765

Adikesavan, Anbu Karani; Karmakar, Sudipan; Pardo, Patricia; Wang, Liguo; Liu, Shuang; Li, Wei

2014-01-01

116

A Conserved Gammaherpesvirus Protein Kinase Targets Histone Deacetylases 1 and 2 To Facilitate Viral Replication in Primary Macrophages  

PubMed Central

Gammaherpesviruses are ubiquitious pathogens that establish lifelong infection and are associated with several malignancies. All gammaherpesviruses encode a conserved protein kinase that facilitates viral replication and chronic infection and thus represents an attractive therapeutic target. In this study, we identify a novel function of gammaherpesvirus protein kinase as a regulator of class I histone deacetylases (HDAC). Mouse gammaherpesvirus 68 (MHV68)-encoded protein kinase orf36 interacted with HDAC1 and 2 and prevented association of these HDACs with the viral promoter driving expression of RTA, a critical immediate early transcriptional activator. Furthermore, the ability to interact with HDAC1 and 2 was not limited to the MHV68 orf36, as BGLF4, a related viral protein kinase encoded by Epstein-Barr virus, interacted with HDAC1 in vitro. Importantly, targeting of HDAC1 and 2 by orf36 was independent of the kinase's enzymatic activity. Additionally, orf36 expression, but not its enzymatic activity, induced changes in the global deacetylase activity observed in infected primary macrophages. Combined deficiency of HDAC1 and 2 rescued attenuated replication and viral DNA synthesis of the orf36 null MHV68 mutant, indicating that the regulation of HDAC1 and 2 by orf36 was relevant for viral replication. Understanding the mechanism by which orf36 facilitates viral replication, including through HDAC targeting, will facilitate the development of improved therapeutics against gammaherpesvirus kinases. PMID:23616648

Mounce, Bryan C.; Mboko, Wadzanai P.; Bigley, Tarin M.; Terhune, Scott S.

2013-01-01

117

Pressure overload-induced cardiac hypertrophy response requires janus kinase 2-histone deacetylase 2 signaling.  

PubMed

Pressure overload induces cardiac hypertrophy through activation of Janus kinase 2 (Jak2), however, the underlying mechanisms remain largely unknown. In the current study, we tested whether histone deacetylase 2 (HDAC2) was involved in the process. We found that angiotensin II (Ang-II)-induced re-expression of fetal genes (Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)) in cultured cardiomyocytes was prevented by the Jak2 inhibitor AG-490 and HDAC2 inhibitor Trichostatin-A (TSA), or by Jak2/HDAC2 siRNA knockdown. On the other hand, myocardial cells with Jak2 or HDAC2 over-expression were hyper-sensitive to Ang-II. In vivo, pressure overload by transverse aorta binding (AB) induced a significant cardiac hypertrophic response as well as re-expression of ANP and BNP in mice heart, which were markedly reduced by AG-490 and TSA. Significantly, AG-490, the Jak2 inhibitor, largely suppressed pressure overload-/Ang-II-induced HDAC2 nuclear exportation in vivo and in vitro. Meanwhile, TSA or HDAC2 siRNA knockdown reduced Ang-II-induced ANP/BNP expression in Jak2 over-expressed H9c2 cardiomyocytes. Together, these results suggest that HDAC2 might be a downstream effector of Jak2 to mediate cardiac hypertrophic response by pressure overload or Ang-II. PMID:25380525

Ying, Huang; Xu, Mao-Chun; Tan, Jing-Hua; Shen, Jing-Hua; Wang, Hao; Zhang, Dai-Fu

2014-01-01

118

Neural stem cell differentiation is dictated by distinct actions of nuclear receptor corepressors and histone deacetylases.  

PubMed

Signaling factors including retinoic acid (RA) and thyroid hormone (T3) promote neuronal, oligodendrocyte, and astrocyte differentiation of cortical neural stem cells (NSCs). However, the functional specificity of transcriptional repressor checkpoints controlling these differentiation programs remains unclear. Here, we show by genome-wide analysis that histone deacetylase (HDAC)2 and HDAC3 show overlapping and distinct promoter occupancy at neuronal and oligodendrocyte-related genes in NSCs. The absence of HDAC3, but not HDAC2, initiated a neuronal differentiation pathway in NSCs. The ablation of the corepressor NCOR or HDAC2, in conjunction with T3 treatment, resulted in increased expression of oligodendrocyte genes, revealing a direct HDAC2-mediated repression of Sox8 and Sox10 expression. Interestingly, Sox10 was required also for maintaining the more differentiated state by repression of stem cell programming factors such as Sox2 and Sox9. Distinct and nonredundant actions of NCORs and HDACs are thus critical for control of lineage progression and differentiation programs in neural progenitors. PMID:25241747

Castelo-Branco, Gonçalo; Lilja, Tobias; Wallenborg, Karolina; Falcão, Ana M; Marques, Sueli C; Gracias, Aileen; Solum, Derek; Paap, Ricardo; Walfridsson, Julian; Teixeira, Ana I; Rosenfeld, Michael G; Jepsen, Kristen; Hermanson, Ola

2014-09-01

119

Radionuclide labeling and evaluation of candidate radioligands for PET imaging of histone deacetylase in the brain.  

PubMed

Histone deacetylases (HDACs) regulate gene expression by inducing conformational changes in chromatin. Ever since the discovery of a naturally occurring HDAC inhibitor, trichostatin A (TSA) stimulated the recent development of suberoylanilide (SAHA, Zolinza®), HDAC has become an important molecular target for drug development. This has created the need to develop specific in vivo radioligands to study epigenetic regulation and HDAC engagement for drug development for diseases including cancer and psychiatric disorders. 6-([(18)F]Fluoroacetamido)-1-hexanoicanilide ([(18)F]FAHA) was recently developed as a HDAC substrate and shows moderate blood-brain barrier (BBB) permeability and specific signal (by metabolic trapping/or deacetylation) but rapid metabolism. Here, we report the radiosynthesis of two carbon-11 labeled candidate radiotracers (substrate- and inhibitor-based radioligand) for HDAC and their evaluation in non-human primate brain. PET studies showed very low brain uptake and rapid metabolism of both labeled compounds but revealed a surprising enhancement of brain penetration by F for H substitution when comparing one of these to [(18)F]FAHA. Further structural refinement is needed for the development of brain-penetrant, metabolically stable HDAC radiotracers and to understand the role of fluorine substitution on brain penetration. PMID:24210501

Seo, Young Jun; Muench, Lisa; Reid, Alicia; Chen, Jinzhu; Kang, Yeona; Hooker, Jacob M; Volkow, Nora D; Fowler, Joanna S; Kim, Sung Won

2013-12-15

120

Sulforaphane destabilizes the androgen receptor in prostate cancer cells by inactivating histone deacetylase 6  

PubMed Central

High consumption of cruciferous vegetables is associated with a reduced risk of prostate cancer in epidemiological studies. There is preliminary evidence that sulforaphane, derived from glucoraphanin found in a number of crucifers, may prevent and induce regression of prostate cancer and other malignancies in preclinical models, but the mechanisms that may explain these effects are not fully defined. Recent reports show that sulforaphane may impair prostate cancer growth through inhibition of histone deacetylases, which are up-regulated in cancer. Indeed, one of these enzymes, histone deacetylase 6 (HDAC6), influences the acetylation state of a key androgen receptor (AR) chaperone, HSP90. AR is the central signaling pathway in prostate cancer, and its inhibition is used for both prevention and treatment of this disease. However, it is not known whether the effects of sulforaphane involve suppression of AR. We hypothesized that sulforaphane treatment would lead to hyperacetylation of HSP90 and that this would destabilize AR and attenuate AR signaling. We confirmed this by demonstrating that sulforaphane enhances HSP90 acetylation, thereby inhibiting its association with AR. Moreover, AR is subsequently degraded in the proteasome, which leads to reduced AR target gene expression and reduced AR occupancy at its target genes. Finally, sulforaphane inhibits HDAC6 deacetylase activity, and the effects of sulforaphane on AR protein are abrogated by overexpression of HDAC6 and mimicked by HDAC6 siRNA. The inactivation by sulforaphane of HDAC6-mediated HSP90 deacetylation and consequent attenuation of AR signaling represents a newly defined mechanism that may help explain this agent's effects in prostate cancer. PMID:19805354

Gibbs, Angela; Schwartzman, Jacob; Deng, Vivianne; Alumkal, Joshi

2009-01-01

121

Histone deacetylase inhibition suppresses myogenin-dependent atrogene activation in spinal muscular atrophy mice  

PubMed Central

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease caused by mutations in the survival of motor neuron 1 (SMN1) gene and deficient expression of the ubiquitously expressed SMN protein. Pathologically, SMA is characterized by motor neuron loss and severe muscle atrophy. During muscle atrophy, the E3 ligase atrogenes, atrogin-1 and muscle ring finger 1 (MuRF1), mediate muscle protein breakdown through the ubiquitin proteasome system. Atrogene expression can be induced by various upstream regulators. During acute denervation, they are activated by myogenin, which is in turn regulated by histone deacetylases 4 and 5. Here we show that atrogenes are induced in SMA model mice and in SMA patient muscle in association with increased myogenin and histone deacetylase-4 (HDAC4) expression. This activation during both acute denervation and SMA disease progression is suppressed by treatment with a histone deacetylase inhibitor; however, this treatment has no effect when atrogene induction occurs independently of myogenin. These results indicate that myogenin-dependent atrogene induction is amenable to pharmacological intervention with histone deacetylase inhibitors and help to explain the beneficial effects of these agents on SMA and other denervating diseases. PMID:22798624

Bricceno, Katherine V.; Sampognaro, Paul J.; Van Meerbeke, James P.; Sumner, Charlotte J.; Fischbeck, Kenneth H.; Burnett, Barrington G.

2012-01-01

122

Decreased histone deacetylase 2 impairs Nrf2 activation by oxidative stress  

SciTech Connect

Research highlights: {yields} Nrf2 anti-oxidant function is impaired when HDAC activity is inhibited. {yields} HDAC inhibition decreases Nrf2 protein stability. {yields} HDAC2 is involved in reduced Nrf2 stability and both correlate in COPD samples. {yields} HDAC inhibition increases Nrf2 acetylation. -- Abstract: Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a crucial role in cellular defence against oxidative stress by inducing the expression of multiple anti-oxidant genes. However, where high levels of oxidative stress are observed, such as chronic obstructive pulmonary disease (COPD), Nrf2 activity is reduced, although the molecular mechanism for this defect is uncertain. Here, we show that down-regulation of histone deacetylase (HDAC) 2 causes Nrf2 instability, resulting in reduced anti-oxidant gene expression and increase sensitivity to oxidative stress. Although Nrf2 protein was clearly stabilized after hydrogen peroxide (H{sub 2}O{sub 2}) stimulation in a bronchial epithelial cell line (BEAS2B), Nrf2 stability was decreased and Nrf2 acetylation increased in the presence of an HDAC inhibitor, trichostatin A (TSA). TSA also reduced Nrf2-regulated heme-oxygenase-1 (HO-1) expression in these cells, and this was confirmed in acute cigarette-smoke exposed mice in vivo. HDAC2 knock-down by RNA interference resulted in reduced H{sub 2}O{sub 2}-induced Nrf2 protein stability and activity in BEAS2B cells, whereas HDAC1 knockdown had no effect. Furthermore, monocyte-derived macrophages obtained from healthy volunteers (non-smokers and smokers) and COPD patients showed a significant correlation between HDAC2 expression and Nrf2 expression (r = 0.92, p < 0.0001). Thus, reduced HDAC2 activity in COPD may account for increased Nrf2 acetylation, reduced Nrf2 stability and impaired anti oxidant defences.

Mercado, Nicolas [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom)] [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom); Thimmulappa, Rajesh [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States)] [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States); Thomas, Catherine M.R.; Fenwick, Peter S.; Chana, Kirandeep K.; Donnelly, Louise E. [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom)] [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom); Biswal, Shyam [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States)] [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States); Ito, Kazuhiro [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom)] [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom); Barnes, Peter J., E-mail: p.j.barnes@imperial.ac.uk [Airway Disease Section, National Heart and Lung Institute, Imperial College, London SW3 6LY (United Kingdom)

2011-03-11

123

Histone deacetylase 3 modulates Tbx5 activity to regulate early cardiogenesis.  

PubMed

Congenital heart defects often result from improper differentiation of cardiac progenitor cells. Although transcription factors involved in cardiac progenitor cell differentiation have been described, the associated chromatin modifiers in this process remain largely unknown. Here we show that mouse embryos lacking the chromatin-modifying enzyme histone deacetylase 3 (Hdac3) in cardiac progenitor cells exhibit precocious cardiomyocyte differentiation, severe cardiac developmental defects, upregulation of Tbx5 target genes and embryonic lethality. Hdac3 physically interacts with Tbx5 and modulates its acetylation to repress Tbx5-dependent activation of cardiomyocyte lineage-specific genes. These findings reveal that Hdac3 plays a critical role in cardiac progenitor cells to regulate early cardiogenesis. PMID:24565863

Lewandowski, Sara L; Janardhan, Harish P; Smee, Kevin M; Bachman, Marcos; Sun, Zheng; Lazar, Mitchell A; Trivedi, Chinmay M

2014-07-15

124

Functional analysis of histone deacetylase and its role in stress response, drug resistance and solid-state cultivation in Aspergillus oryzae.  

PubMed

In the eukaryotic cell, histone deacetylases (HDACs) play key roles in the regulation of fundamental cellular process such as development regulation, stress response, secondary metabolism and genome integrity. Here, we provide a comprehensive phenotypic analysis using HDAC disruptants in Aspergillus oryzae. Our study revealed that four HDACs, hdaA/Aohda1, hdaB/Aorpd3, hdaD/Aohos2 and hst4/AohstD were involved in stress response, cell wall synthesis and chromatin integrity in A. oryzae. Osmotic stress sensitivity of HDAC disruptants differed between plate cultures and liquid cultures, suggesting that HDACs adapt to the difference environmental conditions. Using a common A. oryzae fermentation medium, rice-koji, we also characterized HDACs related to growth and enzyme production to investigate which HDACs will be required for adaptation to environmental conditions and stress resistances. Because HDACs are widely conserved, our study has broad applications and may inform work with filamentous fungi and other eukaryote. PMID:24613105

Kawauchi, Moriyuki; Iwashita, Kazuhiro

2014-08-01

125

Histone deacetylases are required for amphibian tail and limb regeneration but not development.  

PubMed

Amphibians such as Xenopus laevis and Ambystoma mexicanum are capable of whole structure regeneration. However, transcriptional control over these events is not well understood. Here, we investigate the role of histone deacetylase (HDAC) enzymes in regeneration using HDAC inhibitors. The class I/II HDAC inhibitor valproic acid (VPA) inhibits tail regeneration in embryos of the anuran amphibian Xenopus laevis, confirming a recent report by others (Tseng et al., 2011). This inhibition correlates with a sixfold reduction in endogenous HDAC activity. VPA also inhibited tail regeneration in post-refractory stage Xenopus larvae and larvae of the urodele A. mexicanum (axolotl). Furthermore, Xenopus limb regeneration was also significantly impaired by post-amputation treatment with VPA, suggesting a general requirement for HDAC activity in the process of appendage regeneration in amphibians. The most potent inhibition of tail regeneration was observed following treatment with VPA during the wound healing, pre-blastema phase. A second HDAC inhibitor, sodium butyrate, was also shown to inhibit tail regeneration. While both VPA and sodium butyrate are reported to block sodium channel function as well as HDACs, regeneration was not inhibited by valpromide, an analogue of VPA that lacks HDAC inhibition but retains sodium channel blocking activity. Finally, although VPA is a known teratogen, we show that neither tailbud nor limb bud development are affected by exposure to this compound. We conclude that histone deacetylation is specifically required for the earliest events in appendage regeneration in amphibians, and suggest that this may act as a switch to trigger re-expression of developmental genes. PMID:22947425

Taylor, Amy J; Beck, Caroline W

2012-01-01

126

The histone deacetylase inhibitor trichostatin a promotes totipotency in the male gametophyte.  

PubMed

The haploid male gametophyte, the pollen grain, is a terminally differentiated structure whose function ends at fertilization. Plant breeding and propagation widely use haploid embryo production from in vitro-cultured male gametophytes, but this technique remains poorly understood at the mechanistic level. Here, we show that histone deacetylases (HDACs) regulate the switch to haploid embryogenesis. Blocking HDAC activity with trichostatin A (TSA) in cultured male gametophytes of Brassica napus leads to a large increase in the proportion of cells that switch from pollen to embryogenic growth. Embryogenic growth is enhanced by, but not dependent on, the high-temperature stress that is normally used to induce haploid embryogenesis in B. napus. The male gametophyte of Arabidopsis thaliana, which is recalcitrant to haploid embryo development in culture, also forms embryogenic cell clusters after TSA treatment. Genetic analysis suggests that the HDAC protein HDA17 plays a role in this process. TSA treatment of male gametophytes is associated with the hyperacetylation of histones H3 and H4. We propose that the totipotency of the male gametophyte is kept in check by an HDAC-dependent mechanism and that the stress treatments used to induce haploid embryo development in culture impinge on this HDAC-dependent pathway. PMID:24464291

Li, Hui; Soriano, Mercedes; Cordewener, Jan; Muiño, Jose M; Riksen, Tjitske; Fukuoka, Hiroyuki; Angenent, Gerco C; Boutilier, Kim

2014-01-01

127

A novel histone deacetylase inhibitor Chidamide induces apoptosis of human colon cancer cells  

SciTech Connect

Many studies have demonstrated that histone deacetylase (HDAC) inhibitors induce various tumor cells to undergo apoptosis, and such inhibitors have been used in different clinical trials against different human cancers. In this study, we designed and synthesized a novel HDAC inhibitor, Chidamide. We showed that Chidamide was able to increase the acetylation levels of histone H3 and to inhibit the PI3K/Akt and MAPK/Ras signaling pathways, which resulted in arresting colon cancer cells at the G1 phase of the cell cycle and promoting apoptosis. As a result, the proliferation of colon cancer cells was suppressed in vitro. Our data support the potential application of Chidamide as an anticancer agent in treating colon cancer. Future studies are needed to demonstrate its in vivo efficacy.

Liu, Lin [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China)] [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China); Chen, Baoan, E-mail: wenyu811@126.com [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China)] [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China); Qin, Shukui [Chinese PLA Cancer Center, The 81st PLA Hospital, Nanjing 210002, Jiangsu (China)] [Chinese PLA Cancer Center, The 81st PLA Hospital, Nanjing 210002, Jiangsu (China); Li, Suyi; He, Xiangming [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China)] [Department of Oncology, Zhong-Da Hospital of Southeast University, Nanjing 210009, Jiangsu (China); Qiu, Shaomin; Zhao, Wei; Zhao, Hong [Department of Internal Medicine, Nanjing Municipal Cancer Hospital, Nanjing 210003, Jiangsu (China)] [Department of Internal Medicine, Nanjing Municipal Cancer Hospital, Nanjing 210003, Jiangsu (China)

2010-02-05

128

Histone Deacetylase Inhibitor Enhances Recovery after AKI  

PubMed Central

At present, there are no effective therapies to ameliorate injury, accelerate recovery, or prevent postinjury fibrosis after AKI. Here, we sought to identify candidate compounds that accelerate recovery after AKI by screening for small molecules that increase proliferation of renal progenitor cells in zebrafish embryos. One compound identified from this screen was the histone deacetylase inhibitor methyl-4-(phenylthio)butanoate, which we subsequently administered to zebrafish larvae and mice 24–48 hours after inducing AKI. In zebrafish, treatment with the compound increased larval survival and proliferation of renal tubular epithelial cells. In mice, treatment accelerated recovery, reduced postinjury tubular atrophy and interstitial fibrosis, and increased the regenerative capacity of actively cycling renal tubular cells by decreasing the number of cells in G2/M arrest. These data suggest that accelerating recovery may be a viable approach to treating AKI and provide proof of concept that a screen in zebrafish embryos can identify therapeutic candidates for kidney injury. PMID:23620402

Cianciolo Cosentino, Chiara; Skrypnyk, Nataliya I.; Brilli, Lauren L.; Chiba, Takuto; Novitskaya, Tatiana; Woods, Clara; West, James; Korotchenko, Vasiliy N.; McDermott, Lee; Day, Billy W.; Davidson, Alan J.; Harris, Raymond C.; de Caestecker, Mark P.

2013-01-01

129

HISTONE DEACETYLASE 9 represses seedling traits in Arabidopsis thaliana dry seeds.  

PubMed

Plant life is characterized by major phase changes. We studied the role of histone deacetylase (HDAC) activity in the transition from seed to seedling in Arabidopsis. Pharmacological inhibition of HDAC stimulated germination of freshly harvested seeds. Subsequent analysis revealed that histone deacetylase 9 (hda9) mutant alleles displayed reduced seed dormancy and faster germination than wild-type plants. Transcriptome meta-analysis comparisons between the hda9 dry seed transcriptome and published datasets demonstrated that transcripts of genes that are induced during imbibition in wild-type prematurely accumulated in hda9-1 dry seeds. This included several genes associated with photosynthesis and photoautotrophic growth such as RuBisCO and RuBisCO activase (RCA). Chromatin immunoprecipitation experiments demonstrated enhanced histone acetylation levels at their loci in young hda9-1 seedlings. Our observations suggest that HDA9 negatively influences germination and is involved in the suppression of seedling traits in dry seeds, probably by transcriptional repression via histone deacetylation. Accordingly, HDA9 transcript is abundant in dry seeds and becomes reduced during imbibition in wild-type seeds. The proposed function of HDA9 is opposite to that of its homologous genes HDA6 and HDA19, which have been reported to repress embryonic properties in germinated seedlings. PMID:25146719

van Zanten, Martijn; Zöll, Christian; Wang, Zhi; Philipp, Christina; Carles, Annaick; Li, Yong; Kornet, Noortje G; Liu, Yongxiu; Soppe, Wim J J

2014-11-01

130

Optimization of the in vitro cardiac safety of hydroxamate-based histone deacetylase inhibitors.  

PubMed

Histone deacetylase (HDAC) inhibitors have shown promise in treating various forms of cancer. However, many HDAC inhibitors from diverse structural classes have been associated with QT prolongation in humans. Inhibition of the human ether a-go-go related gene (hERG) channel has been associated with QT prolongation and fatal arrhythmias. To determine if the observed cardiac effects of HDAC inhibitors in humans is due to hERG blockade, a highly potent HDAC inhibitor devoid of hERG activity was required. Starting with dacinostat (LAQ824), a highly potent HDAC inhibitor, we explored the SAR to determine the pharmacophores required for HDAC and hERG inhibition. We disclose here the results of these efforts where a high degree of pharmacophore homology between these two targets was discovered. This similarity prevented traditional strategies for mitigating hERG binding/modulation from being successful and novel approaches for reducing hERG inhibition were required. Using a hERG homology model, two compounds, 11r and 25i, were discovered to be highly efficacious with weak affinity for the hERG and other ion channels. PMID:21650221

Shultz, Michael D; Cao, Xueying; Chen, Christine H; Cho, Young Shin; Davis, Nicole R; Eckman, Joe; Fan, Jianmei; Fekete, Alex; Firestone, Brant; Flynn, Julie; Green, Jack; Growney, Joseph D; Holmqvist, Mats; Hsu, Meier; Jansson, Daniel; Jiang, Lei; Kwon, Paul; Liu, Gang; Lombardo, Franco; Lu, Qiang; Majumdar, Dyuti; Meta, Christopher; Perez, Lawrence; Pu, Minying; Ramsey, Tim; Remiszewski, Stacy; Skolnik, Suzanne; Traebert, Martin; Urban, Laszlo; Uttamsingh, Vinita; Wang, Ping; Whitebread, Steven; Whitehead, Lewis; Yan-Neale, Yan; Yao, Yung-Mae; Zhou, Liping; Atadja, Peter

2011-07-14

131

Histone Deacetylase Inhibitors Improve the Replication of Oncolytic Herpes Simplex Virus in Breast Cancer Cells  

PubMed Central

New therapies are needed for metastatic breast cancer patients. Oncolytic herpes simplex virus (oHSV) is an exciting therapy being developed for use against aggressive tumors and established metastases. Although oHSV have been demonstrated safe in clinical trials, a lack of sufficient potency has slowed the clinical application of this approach. We utilized histone deacetylase (HDAC) inhibitors, which have been noted to impair the innate antiviral response and improve gene transcription from viral vectors, to enhance the replication of oHSV in breast cancer cells. A panel of chemically diverse HDAC inhibitors were tested at three different doses (<, ?=?, and >LD50) for their ability to modulate the replication of oHSV in breast cancer cells. Several of the tested HDAC inhibitors enhanced oHSV replication at low multiplicity of infection (MOI) following pre-treatment of the metastatic breast cancer cell line MDA-MB-231 and the oHSV-resistant cell line 4T1, but not in the normal breast epithelial cell line MCF10A. Inhibitors of class I HDACs, including pan-selective compounds, were more effective for increasing oHSV replication compared to inhibitors that selectively target class II HDACs. These studies demonstrate that select HDAC inhibitors increase oHSV replication in breast cancer cells and provides support for pre-clinical evaluation of this combination strategy. PMID:24651853

Cody, James J.; Markert, James M.; Hurst, Douglas R.

2014-01-01

132

Targeted deletion of NF-?B p50 diminishes the cardioprotection of histone deacetylase inhibition  

PubMed Central

We have recently demonstrated that the inhibition of histone deacetylases (HDAC) protects the heart against ischemia-reperfusion (I/R) injury. The mechanism by which HDAC inhibition confers myocardial protection remains unknown. The purpose of this study is to investigate whether the disruption of NF-?B p50 would eliminate the protective effects of HDAC inhibition. Wild-type and NF-?B p50-deficient mice were treated with trichostatin A (TSA; 0.1 mg/kg ip), a potent inhibitor of HDACs. Twenty-four hours later, the hearts were perfused in Langendorff model and subjected to 30 min of ischemia and 30 min of reperfusion. Inhibition of HDACs by TSA in wild-type mice produced marked improvements in left ventricular end-diastolic pressure, left ventricular rate pressure product, and the reduction of infarct size compared with non-TSA-treated group. TSA-induced cardioprotection in wild-type animals was absent with genetic deletion of NF-?B p50 subunit. Notably, Western blot displayed a significant increase in nuclear NF-?B p50 and the immunoprecipitation demonstrated a remarkable acetylation of NF-?B p50 at lysine residues following HDAC inhibition. EMSA exhibited a subsequent increase in NF-?B DNA binding activity. Luciferase assay demonstrated an activation of NF-?B by HDAC inhibition. The pretreatment of H9c2 cardiomyoblasts with TSA (50 nmol/l) decreased cell necrosis and increased in cell viability in simulated ischemia. The resistance of H9c2 cardiomyoblasts to simulated ischemia by HDAC inhibition was eliminated by genetic knockdown of NF-?B p50 with transfection of NF-?B p50 short interfering RNA but not scrambled short interfering RNA. These results suggest that NF-?B p50 acetylation and activation play a pivotal role in HDAC inhibition-induced cardioprotection. PMID:20382965

Zhang, L. X.; Zhao, Y.; Cheng, G.; Guo, T. L.; Chin, Y. E.; Liu, P. Y.

2010-01-01

133

Crebinostat: A Novel Cognitive Enhancer that Inhibits Histone Deacetylase Activity and Modulates Chromatin-Mediated Neuroplasticity  

PubMed Central

Long-term memory formation is known to be critically dependent upon de novo gene expression in the brain. As a consequence, pharmacological enhancement of the transcriptional processes mediating long-term memory formation provides a potential therapeutic strategy for cognitive disorders involving aberrant neuroplasticity. Here we focus on the identification and characterization of small molecule inhibitors of histone deacetylases (HDACs) as enhancers of CREB (cAMP response element-binding protein)-regulated transcription and modulators of chromatin-mediated neuroplasticity. Using a CREB reporter gene cell line, we screened a library of small molecules structurally related to known HDAC inhibitors leading to the identification of a probe we termed crebinostat that produced robust activation of CREB-mediated transcription. Further characterization of crebinostat revealed its potent inhibition of the deacetylase activity of recombinant class I HDACs 1, 2, 3, and class IIb HDAC6, with weaker inhibition of the class I HDAC8 and no significant inhibition of the class IIa HDACs 4, 5, 7, and 9. In cultured mouse primary neurons, crebinostat potently induced acetylation of both histone H3 and histone H4 as well as enhanced the expression of the CREB target gene Egr1 (early growth response 1). Using a hippocampus-dependent, contextual fear conditioning paradigm, mice systemically administered crebinostat for a ten day time period exhibited enhanced memory. To gain insight into the molecular mechanisms of memory enhancement by HDAC inhibitors, whole genome transcriptome profiling of cultured mouse primary neurons treated with crebinostat, combined with bioinformatic analyses of CREB-target genes, was performed revealing a highly connected protein-protein interaction network reflecting modules of genes important to synaptic structure and plasticity. Consistent with these findings, crebinostat treatment increased the density of synapsin-1 punctae along dendrites in cultured neurons. Finally, crebinostat treatment of cultured mouse primary neurons was found to upregulate Bdnf (brain-derived neurotrophic factor) and Grn (granulin) and downregulate Mapt (tau) gene expression—genes implicated in aging-related cognitive decline and cognitive disorders. Taken together, these results demonstrate that crebinostat provides a novel probe to modulate chromatin-mediated neuroplasticity and further suggests that pharmacological optimization of selective of HDAC inhibitors may provide an effective therapeutic approach for human cognitive disorders. PMID:22771460

Fass, Daniel M.; Reis, Surya A.; Ghosh, Balaram; Hennig, Krista M.; Joseph, Nadine F.; Zhao, Wen-Ning; Nieland, Thomas J.F.; Guan, Ji-Song; Kuhnle, Chelsea E. Groves; Tang, Weiping; Barker, Douglas D.; Mazitschek, Ralph; Schreiber, Stuart L.; Tsai, Li-Huei; Haggarty, Stephen J.

2012-01-01

134

Histone Deacetylase Inhibitors Equipped with Estrogen Receptor Modulation Activity  

PubMed Central

We described a set of novel histone deacetylase inhibitors (HDACi) equipped with either an antagonist or an agonist of the estrogen receptor (ER) to confer selective activity against breast cancers. These bifunctional compounds potently inhibit HDAC at nanomolar concentrations, and either agonize or antagonize ER? and ER?. The ER antagonist activities of tamoxifen-HDACi conjugates (Tam-HDACi) are nearly identical to those of tamoxifen. Conversely, ethynyl-estradiol HDACi conjugates (EED-HDACi) have attenuated ER agonist activities relative to the parent ethynyl-estradiol. In silico docking analysis provides structural basis for the trends of ER agonism/antagonism and ER subtype selectivity. Excitingly, lead Tam-HDACi conjugates show anticancer activity that is selectively more potent against MCF-7 (ER? positive breast) compared to MDA-MB-231 (triple negative breast cancer), DU145 (prostate cancer) or Vero (non-cancerous cell line). This dual-targeting approach illustrates the utility of designing small molecules with an emphasis on cell-type selectivity, not merely improved potency, working towards a higher therapeutic index at the earliest stages of drug development. PMID:23786452

Gryder, Berkley E.; Rood, Michael K.; Johnson, Kenyetta A.; Patil, Vishal; Raftery, Eric D.; Yao, Li-Pan D.; Rice, Marcie; Azizi, Bahareh; Doyle, Donald F.; Oyelere, Adegboyega K.

2013-01-01

135

Sin3a-associated Hdac1 and Hdac2 are essential for hematopoietic stem cell homeostasis and contribute differentially to hematopoiesis.  

PubMed

Class I histone deacetylases are critical regulators of gene transcription by erasing lysine acetylation. Targeting histone deacetylases using relative non-specific small molecule inhibitors is of major interest in the treatment of cancer, neurological disorders and acquired immune deficiency syndrome. Harnessing the therapeutic potential of histone deacetylase inhibitors requires full knowledge of individual histone deacetylases in vivo. As hematologic malignancies show increased sensitivity towards histone deacetylase inhibitors we targeted deletion of class I Hdac1 and Hdac2 to hematopoietic cell lineages. Here, we show that Hdac1 and Hdac2 together control hematopoietic stem cell homeostasis, in a cell-autonomous fashion. Simultaneous loss of Hdac1 and Hdac2 resulted in loss of hematopoietic stem cells and consequently bone marrow failure. Bone-marrow-specific deletion of Sin3a, a major Hdac1/2 co-repressor, phenocopied loss of Hdac1 and Hdac2 indicating that Sin3a-associated HDAC1/2-activity is essential for hematopoietic stem cell homeostasis. Although Hdac1 and Hdac2 show compensatory and overlapping functions in hematopoiesis, mice expressing mono-allelic Hdac1 or Hdac2 revealed that Hdac1 and Hdac2 contribute differently to the development of specific hematopoietic lineages. PMID:24763403

Heideman, Marinus R; Lancini, Cesare; Proost, Natalie; Yanover, Eva; Jacobs, Heinz; Dannenberg, Jan-Hermen

2014-08-01

136

PET Imaging Demonstrates Histone Deacetylase Target Engagement and Clarifies Brain Penetrance of Known and Novel Small Molecule Inhibitors in Rat.  

PubMed

Histone deacetylase (HDAC) enzymes have been demonstrated as critical components in maintaining chromatin homeostasis, CNS development, and normal brain function. Evidence in mouse models links HDAC expression to learning, memory, and mood-related behaviors; small molecule HDAC inhibitor tool compounds have been used to demonstrate the importance of specific HDAC subtypes in modulating CNS-disease-related behaviors in rodents. So far, no direct evidence exists to understand the quantitative changes in HDAC target engagement that are necessary to alter biochemistry and behavior in a living animal. Understanding the relationship between target engagement and in vivo effect is essential in refining new ways to alleviate disease. We describe here, using positron emission tomography (PET) imaging of rat brain, the in vivo target engagement of a subset of class I/IIb HDAC enzymes implicated in CNS-disease (HDAC subtypes 1, 2, 3, and 6). We found marked differences in the brain penetrance of tool compounds from the hydroxamate and benzamide HDAC inhibitor classes and resolved a novel, highly brain penetrant benzamide, CN147, chronic treatment with which resulted in an antidepressant-like effect in a rat behavioral test. Our work highlights a new translational path for understanding the molecular and behavioral consequences of HDAC target engagement. PMID:25188794

Schroeder, F A; Wang, C; Van de Bittner, G C; Neelamegam, R; Takakura, W R; Karunakaran, A; Wey, H Y; Reis, S A; Gale, J; Zhang, Y L; Holson, E B; Haggarty, S J; Hooker, J M

2014-10-15

137

Regulation of Neuronal Gene Expression and Survival by Basal NMDA Receptor Activity: A Role for Histone Deacetylase 4  

PubMed Central

Neuronal gene expression is modulated by activity via calcium-permeable receptors such as NMDA receptors (NMDARs). While gene expression changes downstream of evoked NMDAR activity have been well studied, much less is known about gene expression changes that occur under conditions of basal neuronal activity. In mouse dissociated hippocampal neuronal cultures, we found that a broad NMDAR antagonist, AP5, induced robust gene expression changes under basal activity, but subtype-specific antagonists did not. While some of the gene expression changes are also known to be downstream of stimulated NMDAR activity, others appear specific to basal NMDAR activity. The genes altered by AP5 treatment of basal cultures were enriched for pathways related to class IIa histone deacetylases (HDACs), apoptosis, and synapse-related signaling. Specifically, AP5 altered the expression of all three class IIa HDACs that are highly expressed in the brain, HDAC4, HDAC5, and HDAC9, and also induced nuclear accumulation of HDAC4. HDAC4 knockdown abolished a subset of the gene expression changes induced by AP5, and led to neuronal death under long-term tetrodotoxin or AP5 treatment in rat hippocampal organotypic slice cultures. These data suggest that basal, but not evoked, NMDAR activity regulates gene expression in part through HDAC4, and, that HDAC4 has neuroprotective functions under conditions of low NMDAR activity. PMID:25392500

Chen, Yelin; Wang, Yuanyuan; Modrusan, Zora

2014-01-01

138

Histone Deacetylase 6 and Heat Shock Protein 90 Control the Functions of Foxp3+ T-Regulatory Cells?  

PubMed Central

Foxp3+ T-regulatory cells (Tregs) are key to immune homeostasis such that their diminished numbers or function can cause autoimmunity and allograft rejection. Foxp3+ Tregs express multiple histone/protein deacetylases (HDACs) that regulate chromatin remodeling, gene expression, and protein function. Pan-HDAC inhibitors developed for oncologic applications enhance Treg production and Treg suppression function but have limited nononcologic utility given their broad actions and various side effects. We show, using HDAC6-deficient mice and wild-type (WT) mice treated with HDAC6-specific inhibitors, that HDAC6 inhibition promotes Treg suppressive activity in models of inflammation and autoimmunity, including multiple forms of experimental colitis and fully major histocompatibility complex (MHC)-incompatible cardiac allograft rejection. Many of the beneficial effects of HDAC6 targeting are also achieved by inhibition of the HDAC6-regulated protein heat shock protein 90 (HSP90). Hence, selective targeting of a single HDAC isoform, HDAC6, or its downstream target, HSP90, can promote Treg-dependent suppression of autoimmunity and transplant rejection. PMID:21444725

de Zoeten, Edwin F.; Wang, Liqing; Butler, Kyle; Beier, Ulf H.; Akimova, Tatiana; Sai, Hong; Bradner, James E.; Mazitschek, Ralph; Kozikowski, Alan P.; Matthias, Patrick; Hancock, Wayne W.

2011-01-01

139

Identification of Highly Selective and Potent Histone Deacetylase 3 Inhibitors Using Click Chemistry-Based Combinatorial Fragment Assembly  

PubMed Central

To find histone deacetylase 3 (HDAC3)-selective inhibitors, a series of 504 candidates was assembled using “click chemistry”, by reacting nine alkynes bearing a zinc-binding group with 56 azide building blocks in the presence of Cu(I) catalyst. Screening of the 504-member triazole library against HDAC3 and other HDAC isozymes led to the identification of potent and selective HDAC3 inhibitors T247 and T326. These compounds showed potent HDAC3 inhibition with submicromolar IC50s, whereas they did not strongly inhibit other isozymes. Compounds T247 and T326 also induced a dose-dependent selective increase of NF-?B acetylation in human colon cancer HCT116 cells, indicating selective inhibition of HDAC3 in the cells. In addition, these HDAC3-selective inhibitors induced growth inhibition of cancer cells, and activated HIV gene expression in latent HIV-infected cells. These findings indicate that HDAC3-selective inhibitors are promising candidates for anticancer drugs and antiviral agents. This work also suggests the usefulness of the click chemistry approach to find isozyme-selective HDAC inhibitors. PMID:23874714

Suzuki, Takayoshi; Kasuya, Yuki; Itoh, Yukihiro; Ota, Yosuke; Zhan, Peng; Asamitsu, Kaori; Nakagawa, Hidehiko; Okamoto, Takashi; Miyata, Naoki

2013-01-01

140

Noninvasive Magnetic Resonance Spectroscopic Pharmacodynamic Markers of a Novel Histone Deacetylase Inhibitor, LAQ824, in Human Colon Carcinoma Cells and Xenografts1  

Microsoft Academic Search

The aim of this work was to use phosphorus magnetic resonance spectroscopy (31P MRS) to investigate the phar- macodynamic effects of LAQ824, a histone deacetylase (HDAC) inhibitor. Human HT29 colon carcinoma cells were examined by 31P MRS after treatment with LAQ824 and another HDAC inhibitor, suberoylanilide hydroxamic acid. HT29 xenografts and tumor extracts were also examined using 31P MRS, pre-

Yuen-Li Chung; Helen Troy; Rebecca Kristeleit; Wynne Aherne; L. Elizabeth Jackson; Peter Atadja; John R. Griffiths; Ian R. Judson; Paul Workman; Martin O. Leach; Mounia Beloueche-Babari

141

Passive Smoking Impairs Histone Deacetylase-2 in Children With Severe Asthma  

PubMed Central

Background: Parental smoking is known to worsen asthma symptoms in children and to make them refractory to asthma treatment, but the molecular mechanism is unclear. Oxidative stress from tobacco smoke has been reported to impair histone deacetylase-2 (HDAC2) via phosphoinositide-3-kinase (PI3K)/Akt activation and, thus, to reduce corticosteroid sensitivity. The aim of this study was to investigate passive smoking-dependent molecular abnormalities in alveolar macrophages (AMs) by comparing passive smoke-exposed children and non-passive smoke-exposed children with uncontrolled severe asthma. Methods: BAL fluid (BALF) was obtained from 19 children with uncontrolled severe asthma (10 non-passive smoking-exposed subjects and nine passive smoking-exposed subjects), and HDAC2 expression/activity, Akt/HDAC2 phosphorylation levels, and corticosteroid responsiveness in AMs were evaluated. Results: Parental smoking reduced HDAC2 protein expression by 54% and activity by 47%, with concomitant enhancement of phosphorylation of Akt1 and HDAC2. In addition, phosphorylation levels of Akt1 correlated positively with HDAC2 phosphorylation levels and negatively with HDAC2 activity. Furthermore, passive smoke exposure reduced the inhibitory effects of dexamethasone on tumor necrosis factor-?-induced CXCL8 release in AMs. There were relatively higher neutrophil counts and CXCL8 concentrations in BALF and lower Asthma Control Test scores compared with non-passive smoke-exposed children with uncontrolled severe asthma. Conclusions: Passive smoking impairs HDAC2 function via PI3K signaling activation, which could contribute to corticosteroid-insensitive inflammation in children with severe asthma. This novel mechanism will be a treatment target in children with severe asthma and stresses the need for a smoke-free environment for asthmatic children. PMID:24030221

Kobayashi, Yoshiki; Bossley, Cara; Gupta, Atul; Akashi, Kenichi; Tsartsali, Lemonia; Mercado, Nicolas; Barnes, Peter J.; Bush, Andrew

2014-01-01

142

Inhibition of histone deacetylases preserves myocardial performance and prevents cardiac remodeling through stimulation of endogenous angiomyogenesis.  

PubMed

We have previously shown that the inhibition of histone deacetylases (HDACs) protects the heart against acute myocardial ischemia and reperfusion injury. We also demonstrated that HDAC inhibition stimulates myogenesis and angiogenesis in a cultured embryonic stem cell model. We investigate whether in vivo inhibition of HDAC preserves cardiac performance and prevents cardiac remodeling in mouse myocardial infarction (MI) through the stimulation of endogenous regeneration. MI was created by ligation of the left descending artery. Animals were divided into three groups: 1) sham group, animals that underwent thoracotomy without MI; 2) MI, animals that underwent MI; and 3) MI + trichostatin A (TSA), MI animals that received a daily intraperitoneal injection of TSA. In addition, infarcted mice received a daily intraperitoneal injection of TSA (0.1 mg/kg), a selective HDAC inhibitor. 5-Bromo-2-deoxyuridine (50 mg/kg) was delivered every other day to pulse-chase label in vivo endogenous cardiac replication. Eight weeks later, the MI hearts showed a reduction in ventricular contractility. HDAC inhibition increased the improvement of myocardial functional recovery after MI, which was associated with the prevention of myocardial remodeling and reduction of myocardial and serum tumor necrosis factor ?. HDAC inhibition enhanced the formation of new myocytes and microvessels, which was consistent with the robust increase in proliferation and cytokinesis in the MI hearts. An increase in angiogenic response was demonstrated in MI hearts receiving TSA treatment. It is noteworthy that TSA treatment significantly inhibited HDAC activity and increased phosphorylation of Akt-1, but decreased active caspase 3. Taken together, our results indicate that HDAC inhibition preserves cardiac performance and mitigates myocardial remodeling through stimulating cardiac endogenous regeneration. PMID:22271820

Zhang, Ling; Qin, Xin; Zhao, Yu; Fast, Loren; Zhuang, Shougang; Liu, Paul; Cheng, Guangmao; Zhao, Ting C

2012-04-01

143

Targeted cancer therapy: giving histone deacetylase inhibitors all they need to succeed  

PubMed Central

Histone deacetylase inhibitors (HDACis) have now emerged as a powerful new class of small-molecule therapeutics acting through the regulation of the acetylation states of histone proteins (a form of epigenetic modulation) and other non-histone protein targets. Over 490 clinical trials have been initiated in the last 10 years, culminating in the approval of two structurally distinct HDACis – SAHA (vorinostat, Zolinza™) and FK228 (romidepsin, Istodax™). However, the current HDACis have serious limitations, including ineffectively low concentrations in solid tumors and cardiac toxicity, which is hindering their progress in the clinic. Herein, we review the primary paradigms being pursued to overcome these hindrances, including HDAC isoform selectivity, localized administration, and targeting cap groups to achieve selective tissue and cell type distribution. PMID:22416777

Gryder, Berkley E; Sodji, Quaovi H; Oyelere, Adegboyega K

2012-01-01

144

Inhibition of Plasmodium falciparum proliferation in vitro by double-stranded RNA directed against malaria histone deacetylase  

SciTech Connect

Acetylation and deacetylation of histones play important roles in transcription regulation, cell cycle progression and development events. The steady state status of histone acetylation is controlled by a dynamic equilibrium between competing histone acetylase and deacetylase (HDAC). We have used long PfHDAC-1 double-stranded (ds)RNA to interfere with its cognate mRNA expression and determined the effect on malaria parasite growth and development. Chloroquine- and pyrimethamine-resistant Plasmodium falciparum K1 strain was exposed to 1-25 {mu}g of dsRNA/ml of culture for 48 h and growth was determined by [{sup 3}H]-hypoxanthine incorporation and microscopic examination. Parasite culture treated with 10 {mu}g/ml pfHDAC-1 dsRNA exhibited 47% growth inhibition when compared with either untreated control or culture treated with an unrelated dsRNA. PfHDAC-1 dsRNA specifically blocked maturation of trophozoite to schizont stages and decreased PfHDAC-1 transcript 44% in treated trophozoites. These results indicate the potential of HDAC-1 as a target for development of novel antimalarials.

Sriwilaijaroen, N. [Faculty of Medicine, Thammasat University (Rangsit Campus), Pathumthani 12120 (Thailand); Boonma, S. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Attasart, P. [Institute of Molecular Biology and Genetics, Mahidol University, Salaya, Nakornpathom 73170 (Thailand); Pothikasikorn, J. [Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Panyim, S. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Institute of Molecular Biology and Genetics, Mahidol University, Salaya, Nakornpathom 73170 (Thailand); Noonpakdee, W. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand)], E-mail: scwnp@mahidol.ac.th

2009-04-03

145

Valproic acid and other histone deacetylase inhibitors induce microglial apoptosis and attenuate lipopolysaccharide-induced dopaminergic neurotoxicity  

Microsoft Academic Search

Valproic acid (VPA), a widely prescribed drug for seizures and bipolar disorder, has been shown to be an inhibitor of histone deacetylase (HDAC). Our previous study has demonstrated that VPA pretreatment reduces lipopolysaccharide (LPS)-induced dopaminergic (DA) neurotoxicity through the inhibition of microglia over-activation. The aim of this study was to determine the mechanism underlying VPA-induced attenuation of microglia over-activation using

P. S. Chen; C.-C. Wang; C. D. Bortner; G.-S. Peng; X. Wu; H. Pang; R.-B. Lu; P.-W. Gean; D.-M. Chuang; J.-S. Hong

2007-01-01

146

Effects of histone deacetylase inhibitor oxamflatin on in vitro porcine somatic cell nuclear transfer embryos.  

PubMed

Low cloning efficiency is considered to be caused by the incomplete or aberrant epigenetic reprogramming of differentiated donor cells in somatic cell nuclear transfer (SCNT) embryos. Oxamflatin, a novel class of histone deacetylase inhibitor (HDACi), has been found to improve the in vitro and full-term developmental potential of SCNT embryos. In the present study, we studied the effects of oxamflatin treatment on in vitro porcine SCNT embryos. Our results indicated that the rate of in vitro blastocyst formation of SCNT embryos treated with 1 ?M oxamflatin for 15 h postactivation was significantly higher than all other treatments. Treatment of oxamflatin decreased the relative histone deacetylase (HDAC) activity in cloned embryos and resulted in hyperacetylation levels of histone H3 at lysine 9 (AcH3K9) and histone H4 at lysine 5 (AcH4K5) at pronuclear, two-cell, and four-cell stages partly through downregulating HDAC1. The suppression of HDAC6 through oxamflatin increased the nonhistone acetylation level of ?-tubulin during the mitotic cell cycle of early SCNT embryos. In addition, we demonstrated that oxamflatin downregulated DNA methyltransferase 1 (DNMT1) expression and global DNA methylation level (5-methylcytosine) in two-cell-stage porcine SCNT embryos. The pluripotency-related gene POU5F1 was found to be upregulated in the oxamflatin-treated group with a decreased DNA methylation tendency in its promoter regions. Treatment of oxamflatin did not change the locus-specific DNA methylation levels of Sus scrofa heterochromatic satellite DNA sequences at the blastocyst stage. Meanwhile, our findings suggest that treatment with HDACi may contribute to maintaining the stable status of cytoskeleton-associated elements, such as acetylated ?-tubulin, which may be the crucial determinants of donor nuclear reprogramming in early SCNT embryos. In summary, oxamflatin treatment improves the developmental potential of porcine SCNT embryos in vitro. PMID:24960409

Hou, Liming; Ma, Fanhua; Yang, Jinzeng; Riaz, Hasan; Wang, Yongliang; Wu, Wangjun; Xia, Xiaoliang; Ma, Zhiyuan; Zhou, Ying; Zhang, Lin; Ying, Wenqin; Xu, Dequan; Zuo, Bo; Ren, Zhuqing; Xiong, Yuanzhu

2014-08-01

147

Protein Aggregates Are Recruited to Aggresome by Histone Deacetylase 6 via Unanchored Ubiquitin C Termini*  

PubMed Central

The aggresome pathway is activated when proteasomal clearance of misfolded proteins is hindered. Misfolded polyubiquitinated protein aggregates are recruited and transported to the aggresome via the microtubule network by a protein complex consisting of histone deacetylase 6 (HDAC6) and the dynein motor complex. The current model suggests that HDAC6 recognizes protein aggregates by binding directly to polyubiquitinated proteins. Here, we show that there are substantial amounts of unanchored ubiquitin in protein aggregates with solvent-accessible C termini. The ubiquitin-binding domain (ZnF-UBP) of HDAC6 binds exclusively to the unanchored C-terminal diglycine motif of ubiquitin instead of conjugated polyubiquitin. The unanchored ubiquitin C termini in the aggregates are generated in situ by aggregate-associated deubiquitinase ataxin-3. These results provide structural and mechanistic bases for the role of HDAC6 in aggresome formation and further suggest a novel ubiquitin-mediated signaling pathway, where the exposure of ubiquitin C termini within protein aggregates enables HDAC6 recognition and transport to the aggresome. PMID:22069321

Ouyang, Hui; Ali, Yousuf O.; Ravichandran, Mani; Dong, Aiping; Qiu, Wei; MacKenzie, Farrell; Dhe-Paganon, Sirano; Arrowsmith, Cheryl H.; Zhai, R. Grace

2012-01-01

148

Structural Basis of the Antiproliferative Activity of Largazole a Depsipeptide Inhibitor of the Histone Deacetylases  

SciTech Connect

Largazole is a macrocyclic depsipeptide originally isolated from the marine cyanobacterium Symploca sp., which is indigenous to the warm, blue-green waters of Key Largo, Florida (whence largazole derives its name). Largazole contains an unusual thiazoline-thiazole ring system that rigidifies its macrocyclic skeleton, and it also contains a lipophilic thioester side chain. Hydrolysis of the thioester in vivo yields largazole thiol, which exhibits remarkable antiproliferative effects and is believed to be the most potent inhibitor of the metal-dependent histone deacetylases (HDACs). Here, the 2.14 {angstrom}-resolution crystal structure of the HDAC8-largazole thiol complex is the first of an HDAC complexed with a macrocyclic inhibitor and reveals that ideal thiolate-zinc coordination geometry is the key chemical feature responsible for its exceptional affinity and biological activity. Notably, the core structure of largazole is conserved in romidepsin, a depsipeptide natural product formulated as the drug Istodax recently approved for cancer chemotherapy. Accordingly, the structure of the HDAC8-largazole thiol complex is the first to illustrate the mode of action of a new class of therapeutically important HDAC inhibitors.

K Cole; D Dowling; M Boone; A Phillips; D Christianson

2011-12-31

149

Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity.  

PubMed

Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9-Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity. PMID:24747564

Herr, Michael J; Longhurst, Celia M; Baker, Benjamin; Homayouni, Ramin; Speich, Henry E; Kotha, Jayaprakash; Jennings, Lisa K

2014-05-16

150

The effect of combined treatment with cisplatin and histone deacetylase inhibitors on HeLa cells  

PubMed Central

Objective To investigate the combined effects of cisplatin and the histone deacetylase (HDAC) inhibitors suberoylanilide hydroxamic acid (SAHA) or sirtinol on HeLa cells and assess the mechanism underlying HDAC inhibitor-cisplatin synergy. Methods The antineoplastic actions of cisplatin, SAHA and sirtinol, alone and in combination, were evaluated using the tetrazolium dye-based MTT cell proliferation assay, DAPI nuclear staining and cytotoxicity analysis. Results Exposure to cisplatin, SAHA or sirtinol alone induced a dose-dependent reduction in HeLa cell viability. Combined treatment with cisplatin and SAHA or sirtinol was significantly more cytotoxic than cisplatin alone. Individually, cisplatin, SAHA and sirtinol activated caspase-3 and induced apoptosis, but the effects of combined treatment were greater. Importantly, both HDAC inhibitors dose-dependently inhibited the expression of the antiapoptotic proteins Bcl-2 and x-linked inhibitor of apoptosis protein (XIAP). Conclusion The combination of cisplatin and SAHA or sirtinol had synergistic effect on the HeLa cell viability. This potentiation of cisplatin activity was associated with HDAC inhibitor-mediated down-regulation of Bcl-2 and XIAP. These may result from the relaxation of chromatin by these HDAC inhibitors that increase cisplatin sensitivity by enhancing the accessibility of DNA to cisplatin and transcriptional regulators. PMID:21278889

Jin, Ke Long; Park, Jeong-Yeol; Noh, Eun Joo; Hoe, Kwang Lae; Lee, Joo Hak; Kim, Jong-Hyeok

2010-01-01

151

Nuclear export of histone deacetylase 7 during thymic selection is required for immune self-tolerance  

PubMed Central

Histone deacetylase 7 (HDAC7) is a T-cell receptor (TCR) signal-dependent regulator of differentiation that is highly expressed in CD4/CD8 double-positive (DP) thymocytes. Here, we examine the effect of blocking TCR-dependent nuclear export of HDAC7 during thymic selection, through expression of a signal-resistant mutant of HDAC7 (HDAC7-?P) in thymocytes. We find that HDAC7-?P transgenic thymocytes exhibit a profound block in negative thymic selection, but can still undergo positive selection, resulting in the escape of autoreactive T cells into the periphery. Gene expression profiling reveals a comprehensive suppression of the negative selection-associated gene expression programme in DP thymocytes, associated with a defect in the activation of MAP kinase pathways by TCR signals. The consequence of this block in vivo is a lethal autoimmune syndrome involving the exocrine pancreas and other abdominal organs. These experiments establish a novel molecular model of autoimmunity and cast new light on the relationship between thymic selection and immune self-tolerance. PMID:23103766

Kasler, Herbert G; Lim, Hyung W; Mottet, Denis; Collins, Amy M; Lee, Intelly S; Verdin, Eric

2012-01-01

152

Quinazolin-4-one derivatives as selective histone deacetylase-6 inhibitors for the treatment of Alzheimer's disease.  

PubMed

Novel quinazolin-4-one derivatives containing a hydroxamic acid moiety were designed and synthesized. All compounds were subjected to histone deacetylase (HDAC) enzymatic assays to identify selective HDAC6 inhibitors with nanomolar IC50 values. (E)-3-(2-Ethyl-7-fluoro-4-oxo-3-phenethyl-3,4-dihydroquinazolin-6-yl)-N-hydroxyacrylamide, 4b, is the most potent HDAC6 inhibitor (IC50, 8 nM). In vitro, these compounds induced neurite outgrowth accompanied by growth-associated protein 43 expression, and they enhanced the synaptic activities of PC12 and SH-SY5Y neuronal cells without producing toxic or mitogenic effects. Several of the compounds dramatically increased nonhistone protein acetylation, specifically of ?-tubulin. Some of the more potent HDAC6 inhibitors decreased zinc-mediated ?-amyloid aggregation in vitro. N-Hydroxy-3-(2-methyl-4-oxo-3-phenethyl-3,4-dihydro-quinazolin-7-yl)-acrylamide, 3f, the most promising drug candidate, selectively inhibits HDAC6 (IC50, 29 nM), practically does not affect human ether-a-go-go-related membrane channel activity (IC50 >10 ?M) or cytochrome P450 activity (IC50 >6.5 ?M) in vitro, and significantly improves learning-based performances of mice with ?-amyloid-induced hippocampal lesions. PMID:23905680

Yu, Chao-Wu; Chang, Pei-Teh; Hsin, Ling-Wei; Chern, Ji-Wang

2013-09-12

153

Development of a fluorogenic probe based on a DNA staining dye for continuous monitoring of the histone deacetylase reaction.  

PubMed

We designed a simple, rapid, and continuous method for the detection of the activity of histone deacetylases (HDACs), which are key enzymes involved in epigenetic gene regulation, using a DNA-based fluorogenic probe. We designed and synthesized a fluorogenic probe, BOXTO-GK(Ac)G, which is a DNA staining dye-peptide conjugate containing an acetylated lysine. The DNA-dependent fluorescence of BOXTO-GK(Ac)G was greatly enhanced upon deacetylation of the acetylated lysine moiety, owing to the increased DNA binding ability of the probe. The HDAC reaction was detected through a simple procedure that combined this probe with DNA. Our detection system monitored the enzymatic reaction in real time and could be applied to the inhibition assay. These findings demonstrated that our system might be a useful tool for the analysis of HDAC function and for the evaluation of the inhibitor potencies of drug candidates that target HDACs. PMID:25004201

Minoshima, Masafumi; Matsumoto, Tetsuaki; Kikuchi, Kazuya

2014-08-01

154

Histone Deacetylase 2 in the Mouse Hippocampus: Attenuation of Age-Related Increase by Caloric Restriction  

PubMed Central

The aging process in the hippocampus is associated with aberrant epigenetic marks, such as DNA methylation and histone tail alterations. Recent evidence suggests that caloric restriction (CR) can potentially delay the aging process, while upregulation of antioxidants may also have a beneficial effect in this respect. We have recently observed that CR attenuates age-related changes in the levels of the epigenetic molecules DNA methyltransferase 3a, 5-methylcytidine (5-mC) and 5-hydroxymethylcytosine in the mouse hippocampus while overexpression of the antioxidant Cu/Zn superoxide dismutase 1 (SOD1) does not. However, the impact of aging on the levels of histone-modifying enzymes such as histone deacetylase 2 (HDAC2) in the hippocampus has not been studied in much detail. Here, we investigated immunoreactivity (IR) of HDAC2 in three subregions of the hippocampus (dentate gyrus, CA3 and CA1-2) of mice taken from large cohorts of aging wild-type and transgenic mice overexpressing normal human SOD1, which were kept under normal diet or CR from weaning onwards. Independent from the genotype, aging (between 12 and 24 months) increased levels of HDAC2 IR in the hippocampus. Moreover, CR prevented this age-related increase, particularly in the CA3 and CA1-2 subregions, while SOD1 overexpression did not. Quantitative image analyses showed that HDAC2 IR correlated positively with 5-mC IR while these markers were shown to colocalize in the nucleus of hippocampal cells. Together with recent literature reports, these findings suggest that altered levels of epigenetic regulatory proteins including HDAC2 regulate age-related changes in the mouse hippocampus and that CR may prevent these age-related changes. PMID:24093534

Chouliaras, Leonidas; van den Hove, Daniel L.A.; Kenis, Gunter; van Draanen, Michael; Hof, Patrick R.; van Os, Jim; Steinbusch, Harry W.M.; Schmitz, Christoph; Rutten, Bart P.F.

2014-01-01

155

Histone Deacetylase Inhibitors as Therapeutic Agents for Acute Central Nervous System Injuries  

PubMed Central

Histone deacetylase (HDAC) inhibitors are emerging as a novel class of potentially therapeutic agents for treating acute injuries of the central nervous system (CNS). In this review, we summarize data regarding the effects of HDAC inhibitor administration in models of acute CNS injury and discuss issues warranting clinical trials. We have previously shown that the pan-HDAC inhibitor ITF2357, a compound shown to be safe and effective in humans, improves functional recovery and attenuates tissue damage when administered as late as 24 h after injury. Using a well-characterized, clinically relevant mouse model of closed head injury, we demonstrated that a single dose of ITF2357 administered 24 h after injury improves neurobehavioral recovery and reduces tissue damage. ITF2357-induced functional improvement was found to be sustained up to 14 d after trauma and was associated with augmented histone acetylation. Single postinjury administration of ITF2357 also attenuated injury-induced inflammatory responses, as indicated by reduced glial accumulation and activation as well as enhanced caspase-3 expression within microglia/macrophages after treatment. Because no specific therapeutic intervention is currently available for treating brain trauma patients, the ability to affect functional outcome by postinjury administration of HDAC inhibitors within a clinically feasible timeframe may be of great importance. Furthermore, a growing body of evidence indicates that HDAC inhibitors are beneficial for treating various forms of acute CNS injury including ischemic and hemorrhagic stroke. Because HDAC inhibitors are currently approved for other use, they represent a promising new avenue of treatment, and their use in the setting of CNS injury warrants clinical evaluation. PMID:21274503

Shein, Na’ama A; Shohami, Esther

2011-01-01

156

The histone deacetylase inhibitor SAHA acts in synergism with fenretinide and doxorubicin to control growth of rhabdoid tumor cells  

PubMed Central

Background Rhabdoid tumors are highly aggressive malignancies affecting infants and very young children. In many instances these tumors are resistant to conventional type chemotherapy necessitating alternative approaches. Methods Proliferation assays (MTT), apoptosis (propidium iodide/annexin V) and cell cycle analysis (DAPI), RNA expression microarrays and western blots were used to identify synergism of the HDAC (histone deacetylase) inhibitor SAHA with fenretinide, tamoxifen and doxorubicin in rhabdoidtumor cell lines. Results HDAC1 and HDAC2 are overexpressed in primary rhabdoid tumors and rhabdoid tumor cell lines. Targeting HDACs in rhabdoid tumors induces cell cycle arrest and apoptosis. On the other hand HDAC inhibition induces deregulated gene programs (MYCC-, RB program and the stem cell program) in rhabdoid tumors. These programs are in general associated with cell cycle progression. Targeting these activated pro-proliferative genes by combined approaches of HDAC-inhibitors plus fenretinide, which inhibits cyclinD1, exhibit strong synergistic effects on induction of apoptosis. Furthermore, HDAC inhibition sensitizes rhabdoid tumor cell lines to cell death induced by chemotherapy. Conclusion Our data demonstrate that HDAC inhibitor treatment in combination with fenretinide or conventional chemotherapy is a promising tool for the treatment of chemoresistant rhabdoid tumors. PMID:23764045

2013-01-01

157

Image-guided synthesis reveals potent blood-brain barrier permeable histone deacetylase inhibitors.  

PubMed

Recent studies have revealed that several histone deacetylase (HDAC) inhibitors, which are used to study/treat brain diseases, show low blood-brain barrier (BBB) penetration. In addition to low HDAC potency and selectivity observed, poor brain penetrance may account for the high doses needed to achieve therapeutic efficacy. Here we report the development and evaluation of highly potent and blood-brain barrier permeable HDAC inhibitors for CNS applications based on an image-guided approach involving the parallel synthesis and radiolabeling of a series of compounds based on the benzamide HDAC inhibitor, MS-275 as a template. BBB penetration was optimized by rapid carbon-11 labeling and PET imaging in the baboon model and using the imaging derived data on BBB penetration from each compound to feed back into the design process. A total of 17 compounds were evaluated, revealing molecules with both high binding affinity and BBB permeability. A key element conferring BBB penetration in this benzamide series was a basic benzylic amine. These derivatives exhibited 1-100 nM inhibitory activity against recombinant human HDAC1 and HDAC2. Three of the carbon-11 labeled aminomethyl benzamide derivatives showed high BBB penetration (?0.015%ID/cc) and regional binding heterogeneity in the brain (high in thalamus and cerebellum). Taken together this approach has afforded a strategy and a predictive model for developing highly potent and BBB permeable HDAC inhibitors for CNS applications and for the discovery of novel candidate molecules for small molecule probes and drugs. PMID:24780082

Seo, Young Jun; Kang, Yeona; Muench, Lisa; Reid, Alicia; Caesar, Shannon; Jean, Logan; Wagner, Florence; Holson, Edward; Haggarty, Stephen J; Weiss, Philipp; King, Payton; Carter, Pauline; Volkow, Nora D; Fowler, Joanna S; Hooker, Jacob M; Kim, Sung Won

2014-07-16

158

INI1/hSNF5/BAF47 represses c-fos transcription via a histone deacetylase-dependent manner.  

PubMed

INI1/hSNF5/BAF47 is a core component of the hSWI/SNF ATP-dependent chromatin-remodeling complex. It has been suggested that INI1/hSNF5/BAF47 contributes to the regulation of many genes. In this report, we showed that the overexpression of INI1/hSNF5/BAF47 repressed c-fos promoter activity and endogenous c-fos transcription in 293T cells, and the siRNA targeting INI1/hSNF5/BAF47 (siINI1) reversed the inhibitory effect. Histone deacetylation by histone deacetylases (HDACs) was necessary for the repression of c-fos transcription by INI1/hSNF5/BAF47. HDAC and INI1/hSNF5/BAF47 functioned together to suppress c-fos transcription. ChIP experiments demonstrated that INI1/hSNF5/BAF47 could be recruited to the region of c-fos promoter to reduce histone acetylation. Altogether, these data show that INI1/hSNF5/BAF47 represses c-fos transcription via a histone deacetylase (HDAC)-dependent manner. PMID:16219292

Pan, Xuefang; Zhai, Lei; Sun, Ru; Li, Xiaoyun; Zeng, Xianlu

2005-12-01

159

Histone deacetylase 1 reduces NO production in endothelial cells via lysine deacetylation of NO synthase 3.  

PubMed

The lysine acetylation state of nonhistone proteins may be regulated through histone deacetylases (HDACs). Evidence suggests that nitric oxide (NO) synthase 3 (NOS3; endothelial NOS) is posttranslationally lysine acetylated, leading to increased NO production in the endothelium. We tested the hypothesis that NOS3 is lysine acetylated and that upregulated HDAC1-mediated deacetylation leads to reduced NO production in endothelial cells. We determined that NOS3 is basally lysine acetylated in cultured bovine aortic endothelial cells (BAECs). In BAECs, HDAC1 is expressed in the nucleus and cytosol and forms a novel protein-protein interaction with NOS3. Overexpression of HDAC1 in BAECs resulted in a significant reduction in NOS3 lysine acetylation (control = 1.0 ± 0.1 and HDAC1 = 0.59 ± 0.08 arbitrary units, P < 0.01) and significantly blunted basal nitrite production (control 287.7 ± 29.1 and HDAC1 172.4 ± 31.7 pmol·mg(-1)·h(-1), P < 0.05) as well as attenuating endothelin-1-stimulated nitrite production (control = 481.8 ± 50.3 and HDAC1 243.1 ± 48.2 pmol·mg(-1)·h(-1), P < 0.05). While HDAC1 knockdown with small-interfering RNA resulted in no change in NOS3 acetylation level, yet increased basal nitrite production (730.6 ± 99.1 pmol·mg(-1)·h(-1)) and further exaggerated increases in endothelin-1 stimulated nitrite production (1276.9 ± 288.2 pmol·mg(-1)·h(-1)) was observed. Moreover, overexpression or knockdown of HDAC1 resulted in no significant effect on NOS3 protein expression or NOS3 phosphorylation sites T497, S635, or S1179. Thus these data indicate that upregulated HDAC1 decreases NOS3 activity, most likely through direct lysine deacetylation of NOS3. We propose that HDAC1-mediated deacetylation of NOS3 may represent a novel target for endothelial dysfunction. PMID:25015965

Hyndman, Kelly A; Ho, Dao H; Sega, Martiana F; Pollock, Jennifer S

2014-09-01

160

Effect of C7-substitution of 1-arylsulfonyl-5-(N-hydroxyacrylamide)indolines on the selectivity towards a subclass of histone deacetylases.  

PubMed

This study focused on the substitution effect at position C7 of 1-arylsulfonyl-5-(N-hydroxyacrylamide)indolines. Compound , (E)-3-(7-amino-1-(4-methoxyphenylsulfonyl)indolin-5-yl)-N-hydroxyacrylamide, displayed 4- to 14-fold more potent antiproliferative activity than vorinostat (SAHA, ). Notably, possessed specific histone deacetylase (HDAC) inhibitory activity toward HDAC1 and HDAC2, but had no effect on HDAC6, indicating that has the potential to be developed as a class I HDAC inhibitor. In a xenograft tumor model, suppressed the growth of HCT116 cells at 100 mg kg(-1), which led to a TGI (tumor growth inhibition) of 40.3%. Taken together, the C7 substitutions have a crucial effect on class I HDACs, which is beneficial for synthesizing efficient anticancer agents. PMID:25277250

Lee, Hsueh-Yun; Wang, Li-Ting; Li, Yu-Hsuan; Pan, Shiow-Lin; Chen, Yi-Lin; Teng, Che-Ming; Liou, Jing-Ping

2014-10-21

161

An atlas of histone deacetylase expression in breast cancer: fluorescence methodology for comparative semi-quantitative analysis  

PubMed Central

The histone deacetylase inhibitors, suberoylanilide hydroxamic acid (Vorinostat, Zolinza™) and depsipeptide (Romidepsin, Istodax™) have been approved by the US Food and Drug Administration for the treatment of refractory cutaneous T-cell lymphoma. Numerous histone deacetylase inhibitors are currently undergoing clinical trials, predominantly in combination with other cancer modalities, for the treatment of various haematological and solid malignancies. Most of the traditional compounds are known as broad-spectrum or pan-histone deacetylase inhibitors, possessing activity against a number of the 11 metal-dependent enzymes. One of the main questions in the field is whether class- or isoform-specific compounds would offer a therapeutic benefit compared to broad-spectrum inhibitors. Therefore, analysis of the relative expression of the different histone deacetylase enzymes in cancer cells and tissues is important to determine whether there are specific targets. We used a panel of antibodies directed against the 11 known mammalian histone deacetylases to determine expression levels in MCF7 breast cancer cells and in tissue representative of invasive ductal cell carcinoma and ductal carcinoma in situ. Firstly, we utilized a semi-quantitative method based on immunofluorescence staining to examine expression of the different histone deacetylases in MCF7 cells. Our findings indicate high expression levels of HDAC1, 3 and 6 in accordance with findings from others using RT-PCR and immunoblotting. Following validation of our approach we examined the expression of the different isoforms in representative control and breast cancer tissue. In general, our findings indicate higher expression of class I histone deacetylases compared to class II enzymes in breast cancer tissue. Analysis of individual cancer cells in the same tissue indicated marked heterogeneity in the expression of most class I enzymes indicating potential complications with the use of class- or isoform-specific compounds. Overall, our approach can be utilized to rapidly compare, in an unbiased semi-quantitative manner, the differential levels of expression of histone deacetylase enzymes in cells and tissues using widely available imaging software. It is anticipated that such analysis will become increasingly important as class- or isoform-specific histone deacetylase inhibitors become more readily available. PMID:22347520

Ververis, Katherine; Karagiannis, Tom C

2012-01-01

162

Hyposensitivity to Gamma-Aminobutyric Acid in the Ventral Tegmental Area During Alcohol Withdrawal: Reversal by Histone Deacetylase Inhibitors  

PubMed Central

Putative dopaminergic (pDAergic) ventral tegmental area (VTA) neurons have an important role in alcohol addiction. Acute ethanol increases the activity of pDAergic neurons, and withdrawal from repeated ethanol administration produces a decreased sensitivity of pDAergic VTA neurons to GABA. Recent studies show that behavioral changes induced by chronic alcohol are reversed by inhibitors of histone deacetylases (HDACs). Whether HDAC-induced histone modifications regulate changes in GABA sensitivity of VTA pDAergic neurons during withdrawal is unknown. Here, we investigated modulation of withdrawal-induced changes in GABA sensitivity of pDAergic VTA neurons by HDAC inhibitors (HDACi), and also measured the levels of HDAC2, histone (H3-K9) acetylation, and GABA-A?1 receptor (GABA (A-?1) R) subunit in VTA during ethanol withdrawal. Mice were injected intraperitoneally (ip) with either ethanol (3.5?g/kg) or saline twice daily for 3 weeks. In recordings from pDAergic VTA neurons in brain slices from ethanol-withdrawn mice, sensitivity to GABA (50–500??M) was reduced. In brain slices from ethanol-withdrawn mice incubated with the HDACi SAHA (vorinostat) or trichostatin A (TSA) for 2 h, the hyposensitivity of pDAergic VTA neurons to GABA was significantly attenuated. There was no effect of TSA or SAHA on GABA sensitivity of pDAergic VTA neurons from saline-treated mice. In addition, ethanol withdrawal was associated with an increase in levels of HDAC2 and a decrease in histone (H3-K9) acetylation and levels of GABA (A-?1) R subunits in the VTA. Therefore, blockade of upregulation of HDAC2 by HDACi normalizes GABA hyposensitivity of pDAergic neurons developed during withdrawal after chronic ethanol treatment, which suggests the possibility that inhibition of HDACs can reverse ethanol-induced neuroadaptational changes in reward circuitry. PMID:23474591

Arora, Devinder S; Nimitvilai, Sudarat; Teppen, Tara L; McElvain, Maureen A; Sakharkar, Amul J; You, Chang; Pandey, Subhash C; Brodie, Mark S

2013-01-01

163

Inhibition of Histone Deacetylases 1 and 6 Enhances Cytarabine-Induced Apoptosis in Pediatric Acute Myeloid Leukemia Cells  

PubMed Central

Background Pediatric acute myeloid leukemia (AML) remains a challenging disease to treat even with intensified cytarabine-based chemotherapy. Histone deacetylases (HDACs) have been reported to be promising therapeutic targets for treating AML. However, HDAC family members that are involved in chemotherapy sensitivities remain unknown. In this study, we sought to identify members of the HDAC family that are involved in cytarabine sensitivities, and to select the optimal HDACI that is most efficacious when combined with cytarabine for treating children with AML. Methodology Expression profiles of classes I, II, and IV HDACs in 4 pediatric AML cell lines were determined by Western blotting. Inhibition of class I HDACs by different HDACIs was measured post immnunoprecipitation. Individual down-regulation of HDACs in pediatric AML cells was performed with lentiviral shRNA. The effects of cytarabine and HDACIs on apoptosis were determined by flow cytometry analysis. Results Treatments with structurally diverse HDACIs and HDAC shRNA knockdown experiments revealed that down-regulation of both HDACs 1 and 6 is critical in enhancing cytarabine-induced apoptosis in pediatric AML, at least partly mediated by Bim. However, down-regulation of HDAC2 may negatively impact cytarabine sensitivities in the disease. At clinically achievable concentrations, HDACIs that simultaneously inhibited both HDACs 1 and 6 showed the best anti-leukemic activities and significantly enhanced cytarabine-induced apoptosis. Conclusion Our results further confirm that HDACs are bona fide therapeutic targets for treating pediatric AML and suggest that pan-HDACIs may be more beneficial than isoform-specific drugs. PMID:21359182

Xu, Xuelian; Xie, Chengzhi; Edwards, Holly; Zhou, Hui; Buck, Steven A.; Ge, Yubin

2011-01-01

164

Suberoylanilide hydroxamic acid, a histone deacetylase inhibitor, protects dopaminergic neurons from neurotoxin-induced damage  

PubMed Central

BACKGROUND AND PURPOSE Prevention or disease-modifying therapies are critical for the treatment of neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and Huntington's disease. However, no such intervention is currently available. Growing evidence has demonstrated that administration of histone deacetylase (HDAC) inhibitors ameliorates a wide range of neurologic and psychiatric disorders in experimental models. Suberoylanilide hydroxamic acid (SAHA) was the first HDAC inhibitor approved by the Food and Drug Administration for the sole use of cancer therapy. The purpose of this study was to explore the potential new indications of SAHA for therapy of neurodegenerative diseases in in vitro Parkinson's disease models. EXPERIMENTAL APPROACH Mesencephalic neuron–glia cultures and reconstituted cultures were used to investigate neurotrophic and neuroprotective effects of SAHA. We measured toxicity in dopaminergic neurons, using dopamine uptake assay and morphological analysis and expression of neurotrophic substances by enzyme-linked immunosorbent assay and real-time RT PCR. KEY RESULTS In mesencephalic neuron–glia cultures, SAHA displayed dose- and time-dependent prolongation of the survival and protection against neurotoxin-induced neuronal death of dopaminergic neurons. Mechanistic studies revealed that the neuroprotective effects of SAHA were mediated in part by promoting release of neurotrophic factors from astroglia through inhibition of histone deacetylation. CONCLUSION AND IMPLICATIONS The novel neurotrophic and neuroprotective effects of SAHA demonstrated in this study suggest that further study of this HDAC inhibitor could provide a new therapeutic approach to the treatment of neurodegenerative diseases. PMID:21726209

Chen, SH; Wu, HM; Ossola, B; Schendzielorz, N; Wilson, BC; Chu, CH; Chen, SL; Wang, Q; Zhang, D; Qian, L; Li, X; Hong, JS; Lu, RB

2012-01-01

165

Antitumor Action of a Novel Histone Deacetylase Inhibitor, YF479, in Breast Cancer1  

PubMed Central

Accumulating evidence demonstrates important roles for histone deacetylase in tumorigenesis (HDACs), highlighting them as attractive targets for antitumor drug development. Histone deactylase inhibitors (HDACIs), which have shown favorable anti-tumor activity with low toxicity in clinical investigations, are a promising class of anticancer therapeutics. Here, we screened our compound library to explore small molecules that possess anti-HDAC activity and identified a novel HDACI, YF479. Suberoylanilide hydroxamic acid (SAHA), which was the first approved HDAC inhibitor for clinical treatment by the FDA, was as positive control in our experiments. We further demonstrated YF479 abated cell viability, suppressed colony formation and tumor cell motility in vitro. To investigate YF479 with superior pharmacodynamic properties, we developed spontaneous and experimental breast cancer animal models. Our results showed YF479 significantly inhibited breast tumor growth and metastasis in vivo. Further study indicated YF479 suppressed both early and end stages of metastatic progression. Subsequent adjuvant chemotherapy animal experiment revealed the elimination of local-regional recurrence (LRR) and distant metastasis by YF479. More important, YF479 remarkably prolonged the survival of tumor-bearing mice. Intriguingly, YF479 displayed more potent anti-tumor activity in vitro and in vivo compared with SAHA. Together, our results suggest that YF479, a novel HDACI, inhibits breast tumor growth, metastasis and recurrence. In light of these results, YF479 may be an effective therapeutic option in clinical trials for patients burdened by breast cancer. PMID:25220594

Zhang, Tao; Chen, Yihua; Li, Jingjie; Yang, Feifei; Wu, Haigang; Dai, Fujun; Hu, Meichun; Lu, Xiaoling; Peng, Yi; Liu, Mingyao; Zhao, Yongxiang; Yi, Zhengfang

2014-01-01

166

The extinction of morphine-induced conditioned place preference by histone deacetylase inhibition.  

PubMed

Recent evidence suggests that epigenetic mechanisms have an important role in the development of addictive behavior. However, little is known about the role of epigenetic mechanisms in the extinction of morphine-induced behavioral changes. In this study, we will examine the effect of histone deacetylase (HDAC) inhibitors on extinction of morphine-induced conditioned place preference (CPP). To facilitate extinction, rats will be administered an HDAC inhibitor (HDACi) following nonreinforced exposure to the conditioned context. To measure persistence, rats were subject to a reinstatement test using 3 mg/kg dose of morphine. To exclude the effect of repeated NaBut injections themselves on morphine-CPP in the absence of extinction session, rats received injection of either NaBut or vehicle for 8 days. We found that HDAC inhibition during nonconfined extinction or confined extinction consolidation can facilitate extinction of morphine-induced CPP. We also showed that the extinction of drug seeking via HDAC inhibition modulates extinction learning such that reinstatement behavior is significantly attenuated. There is no effect of repeated NaBut injections themselves on morphine-CPP in the absence of extinction session. In conclusion, our results extend earlier reports on the ability of HDACi to modify the behavioral effects of drugs of abuse. Our increasing understanding of these epigenetic mechanisms will provide key answers to basic processes in drug addiction and hopefully provide insight into designing improved treatments for drug addiction. PMID:20691756

Wang, Ru; Zhang, Yan; Qing, Hua; Liu, Mei; Yang, Peng

2010-10-11

167

HDAC6 Deacetylase Activity Is Critical for Lipopolysaccharide-Induced Activation of Macrophages  

PubMed Central

Activated macrophages play an important role in both innate and adaptive immune responses, and aberrant activation of macrophages often leads to inflammatory and immune disorders. However, the molecular mechanisms of how macrophages are activated are not fully understood. In this study, we identify a novel role for histone deacetylse 6 (HDAC6) in lipopolysaccharide (LPS)-induced macrophage activation. Our data show that suppression of HDAC6 activity significantly restrains LPS-induced activation of macrophages and production of pro-inflammatory cytokines. Further study reveals that the regulation of macrophage activation by HDAC6 is independent of F-actin polymerization and filopodium formation; instead, it is mediated by the effects of HDAC6 on cell adhesion and microtubule acetylation. These data thus suggest that HDAC6 is an important regulator of LPS-induced macrophage activation and might be a potential target for the management of inflammatory disorders. PMID:25330030

Liu, Zhu; Ran, Jie; Li, Yuanyuan; Wang, Jian; Yang, Yang; Zhou, Jun; Li, Dengwen; Liu, Min

2014-01-01

168

Development of histone deacetylase inhibitors as therapeutics for neurological disease  

PubMed Central

Postsynthetic modifications of histone and other chromosomal proteins by reversible acetylation and/or methylation regulate many aspects of chromatin dynamics, such as transcription, replication and DNA repair. Aberrant modification states are associated with several neurological and neuromotor diseases. Thus, small molecules that inhibit or activate the enzymes responsible for these chromatin modifications have received considerable attention as potential human therapeutics. This paper summarizes the current state of development of histone deacetylase inhibitors in a variety of neurological diseases. PMID:20177429

Gottesfeld, Joel M; Pandolfo, Massimo

2010-01-01

169

Repeated treatment with electroconvulsive seizures induces HDAC2 expression and down-regulation of NMDA receptor-related genes through histone deacetylation in the rat frontal cortex.  

PubMed

The enzymatic activity of histone deacetylases (HDACs) leads to a histone deacetylation-mediated condensed chromatic structure, resulting in transcriptional repression, which has been implicated in the modifications of neural circuits and behaviors. Repeated treatment with electroconvulsive seizure (ECS) induces changes in histone acetylation, expression of various genes, and intrabrain cellular changes, including neurogenesis. In this study, we examined the effects of repeated ECS on the expression of class I HDACs and related changes in histone modifications and gene expression in the rat frontal cortex. Ten days of repeated ECS treatments (E10X) up-regulated HDAC2 expression at the mRNA and protein levels in the rat frontal cortex compared with sham-treated controls; this was evident in the nuclei of neuronal cells in the prefrontal, cingulate, orbital, and insular cortices. Among the known HDAC2 target genes, mRNA expression of N-methyl-d-aspartate (NMDA) receptor signaling-related genes, including early growth response-1 (Egr1), c-Fos, glutamate receptor, ionotropic, N-methyl d-aspartate 2A (Nr2a), Nr2b, neuritin1 (Nrn1), and calcium/calmodulin-dependent protein kinase II alpha (Camk2?), were decreased, and the histone acetylation of H3 and/or H4 proteins was also reduced by E10X. Chromatin immunoprecipitation analysis revealed that HDAC2 occupancy in the promoters of down-regulated genes was increased significantly. Moreover, administration of sodium butyrate, a HDAC inhibitor, during the course of E10X ameliorated the ECS-induced down-regulation of genes in the rat frontal cortex. These findings suggest that induction of HDAC2 by repeated ECS treatment could play an important role in the down-regulation of NMDA receptor signaling-related genes in the rat frontal cortex through histone modification. PMID:24606669

Park, Hong Geun; Yu, Hyun Sook; Park, Soyoung; Ahn, Yong Min; Kim, Yong Sik; Kim, Se Hyun

2014-09-01

170

Santacruzamate A, a potent and selective histone deacetylase inhibitor from the Panamanian marine cyanobacterium cf. Symploca sp.  

PubMed

A dark brown tuft-forming cyanobacterium, morphologically resembling the genus Symploca, was collected during an expedition to the Coiba National Park, a UNESCO World Heritage Site on the Pacific coast of Panama. Phylogenetic analysis of its 16S rRNA gene sequence indicated that it is 4.5% divergent from the type strain for Symploca and thus is likely a new genus. Fractionation of the crude extract led to the isolation of a new cytotoxin, designated santacruzamate A (1), which has several structural features in common with suberoylanilide hydroxamic acid [(2), SAHA, trade name Vorinostat], a clinically approved histone deacetylase (HDAC) inhibitor used to treat refractory cutaneous T-cell lymphoma. Recognition of the structural similarly of 1 and SAHA led to the characterization of santacruzamate A as a picomolar level selective inhibitor of HDAC2, a Class I HDAC, with relatively little inhibition of HDAC4 or HDAC6, both Class II HDACs. As a result, chemical syntheses of santacruzamate A as well as a structurally intriguing hybrid molecule, which blends aspects of both agents (1 and 2), were achieved and evaluated for their HDAC activity and specificity. PMID:24164245

Pavlik, Christopher M; Wong, Christina Y B; Ononye, Sophia; Lopez, Dioxelis D; Engene, Niclas; McPhail, Kerry L; Gerwick, William H; Balunas, Marcy J

2013-11-22

171

Inhibitors of class 1 histone deacetylases reverse contextual memory deficits in a mouse model of Alzheimer's disease.  

PubMed

Alzheimer's disease (AD) is a neurodegenerative disorder characterized clinically by cognitive impairments that progress to dementia and death. The earliest symptoms of AD present as a relatively pure deficit in memory retrieval. Therefore, drug treatments that intervene in the early stages of AD by rescuing memory deficits could be promising therapies to slow, or even reverse progression of the disease. In this study, we tested the potential of systemic histone deacetylase inhibitor (HDACi) treatment to rescue cognitive deficits in a mouse model of AD. APPswe/PS1dE9 mice showed pronounced contextual memory impairments beginning at 6 months of age. Chronic HDACi injections (2-3 weeks) did not alter contextual memory formation in normal mice, but had profound effects in transgenic animals. Injections of sodium valproate, sodium butyrate, or vorinostat (suberoylanilide hydroxamic acid; Zolinza) completely restored contextual memory in these mutant mice. Further behavioral testing of the HDACi-treated transgenic mice showed that the newly consolidated memories were stably maintained over a 2-week period. Measurement of the HDAC isoform selectivity profile of sodium valproate, sodium butyrate, and vorinostat revealed the common inhibition of class I HDACs (HDAC1, 2, 3, 8) with little effect on the class IIa HDAC family members (HDAC4, 5, 7, 9) and inhibition of HDAC6 only by vorinostat. These preclinical results indicate that targeted inhibition of class I HDAC isoforms is a promising avenue for treating the cognitive deficits associated with early stage AD. PMID:20010553

Kilgore, Mark; Miller, Courtney A; Fass, Daniel M; Hennig, Krista M; Haggarty, Stephen J; Sweatt, J David; Rumbaugh, Gavin

2010-03-01

172

Biochemical Analysis of Histone Deacetylase-independent Transcriptional Repression by MeCP2*  

PubMed Central

MeCP2 is an abundant methyl-cytosine-guanine (CG)-binding protein and transcriptional repressor. We developed a biochemical system that exhibits CG methylation-specific transcriptional repression by purified human MeCP2. MeCP2 represses transcription by histone deacetylase (HDAC)-dependent and HDAC-independent mechanisms. Our system appears to recreate the HDAC-independent component of MeCP2-mediated repression and occurs via inhibition of the assembly of transcription preinitiation complexes. At a ratio of approximately one molecule of MeCP2 per two methyl-CG dinucleotides, as found in mammalian neurons, the magnitude of methylation-specific repression was greater than 10-fold. Notably, the HDAC inhibitor trichostatin A had no effect on MeCP2-mediated repression with either naked DNA or chromatin templates. We designed a CG-deficient core promoter that is resistant to MeCP2-mediated repression when placed in a plasmid lacking CG dinucleotides. By using this CG-deficient reporter as a reference, we found that eight CG dinucleotides in the core promoter region are sufficient for strong methylation-specific repression by MeCP2. In contrast, MeCP2 does not repress a construct with 13 CG dinucleotides located ?1.7 kbp upstream of the promoter. Furthermore, by analysis of C-terminally truncated MeCP2 proteins, we found that binding of MeCP2 to methyl-CG dinucleotides is not sufficient for transcriptional repression. Hence, MeCP2-mediated repression is not due to the simple steric blockage of the transcriptional machinery. These experiments suggest that MeCP2 can function as a global methyl-CG-specific, HDAC-independent repressor. This HDAC-independent mechanism of MeCP2-mediated repression may be important in cells, such as mammalian neurons, that have high levels of CG methylation and MeCP2. PMID:23349465

Theisen, Joshua W. M.; Gucwa, James S.; Yusufzai, Timur; Khuong, Mai T.; Kadonaga, James T.

2013-01-01

173

The tumor suppressor kinase LKB1 activates the downstream kinases SIK2 and SIK3 to stimulate nuclear export of class IIa histone deacetylases.  

PubMed

Histone deacetylases 4 (HDAC4), -5, -7, and -9 form class IIa within the HDAC superfamily and regulate diverse physiological and pathological cellular programs. With conserved motifs for phosphorylation-dependent 14-3-3 binding, these deacetylases serve as novel signal transducers that are able to modulate histone acetylation and gene expression in response to extracellular cues. Here, we report that in a PKA-sensitive manner the tumor suppressor kinase LKB1 acts through salt-inducible kinase 2 (SIK2) and SIK3 to promote nucleocytoplasmic trafficking of class IIa HDACs. Both SIK2 and SIK3 phosphorylate the deacetylases at the conserved motifs and stimulate 14-3-3 binding. SIK2 activates MEF2-dependent transcription and relieves repression of myogenesis by the deacetylases. Distinct from SIK2, SIK3 induces nuclear export of the deacetylases independent of kinase activity and 14-3-3 binding. These findings highlight the difference among members of the SIK family and indicate that LKB1-dependent SIK activation constitutes an important signaling module upstream from class IIa deacetylases for regulating cellular programs controlled by MEF2 and other transcription factors. PMID:23393134

Walkinshaw, Donald R; Weist, Ryan; Kim, Go-Woon; You, Linya; Xiao, Lin; Nie, Jianyun; Li, Cathy S; Zhao, Songping; Xu, Minghong; Yang, Xiang-Jiao

2013-03-29

174

[Histone deacetylases: a new class of efficient anti-tumor drugs].  

PubMed

Circa twenty-five years ago, cancer research was dominated by the concept that the origin of cancer was genetic. Thousands of genetic alterations have indeed been identified involving more than hundred different genes in cancer development. Today, the model has evolved: it has been demonstrated that malignancies can be initiated not only through genetic alterations but also through epigenetic deregulations. By altering the expression of gene involved in cell regulation, epigenetic alterations, such as histone acetylation, play a key role in the initiation and progression of neoplasm. It has been shown that an imbalance between the acelylated and deacetylated status of chromatin is significantly involved in the acquisition of a malignant phenotype. Thus, the modulation of the histone acetylation level by histone deacetylase (HDAC) inhibitors could lead to a genetic re-programmation in cancer cells that would favor apoptosis and prevent proliferation. The potential therapeutic value of several HDAC inhibitors for cancer patients has been evaluated in clinical assays with very promising outcome. Indeed, the first inhibitors available for patients has been recently approved for cancer patients tracing the way for a new class of promising anti-cancer therapy modalities. PMID:18789222

Mottet, Denis; Castronovo, Vincent

2008-01-01

175

Rationale for the Development of 2-Aminobenzamide Histone Deacetylase Inhibitors as Therapeutics for Friedreich Ataxia  

PubMed Central

Numerous studies have pointed to histone deacetylase inhibitors as potential therapeutics for various neurodegenerative diseases, and clinical trials with several histone deacetylase inhibitors have been performed or are underway. However, histone deacetylase inhibitors tested to date are either highly cytotoxic or have very low specificities for different histone deacetylase enzymes. Our laboratories have identified a novel class of histone deacetylase inhibitors (2-aminobenzamides) that reverses heterochromatin-mediated silencing of the frataxin (FXN) gene in Friedreich ataxia. We have identified the histone deacetylase enzyme isotype target of these compounds and present evidence that compounds that target this enzyme selectively increase FXN expression from pathogenic alleles. Studies with model compounds show that these histone deacetylase inhibitors increase FXN messenger RNA levels in the brain in mouse models for Friedreich ataxia, relieve neurological symptoms observed in one mouse model, and support the notion that this class of molecules may serve as therapeutics for the human disease. PMID:22764181

Soragni, Elisabetta; Xu, Chunping; Plasterer, Heather L.; Jacques, Vincent; Rusche, James R.; Gottesfeld, Joel M.

2013-01-01

176

In Silico Investigation of Traditional Chinese Medicine Compounds to Inhibit Human Histone Deacetylase 2 for Patients with Alzheimer's Disease  

PubMed Central

Human histone deacetylase 2 (HDAC2) has been identified as being associated with Alzheimer's disease (AD), a neuropathic degenerative disease. In this study, we screen the world's largest Traditional Chinese Medicine (TCM) database for natural compounds that may be useful as lead compounds in the search for inhibitors of HDAC2 function. The technique of molecular docking was employed to select the ten top TCM candidates. We used three prediction models, multiple linear regression (MLR), support vector machine (SVM), and the Bayes network toolbox (BNT), to predict the bioactivity of the TCM candidates. Molecular dynamics simulation provides the protein-ligand interactions of compounds. The bioactivity predictions of pIC50 values suggest that the TCM candidatesm, (?)-Bontl ferulate, monomethylcurcumin, and ningposides C, have a greater effect on HDAC2 inhibition. The structure variation caused by the hydrogen bonds and hydrophobic interactions between protein-ligand interactions indicates that these compounds have an inhibitory effect on the protein. PMID:25045700

Hung, Tzu-Chieh; Lee, Wen-Yuan; Chen, Kuen-Bao; Chan, Yueh-Chiu; Lee, Cheng-Chun

2014-01-01

177

Anti-inflammatory effects of budesonide in human lung fibroblast are independent of histone deacetylase 2  

PubMed Central

Objective and design Reduced expression of histone deacetylase 2 (HDAC2) in alveolar macrophages and epithelial cells may account for reduced response of chronic obstructive pulmonary disease (COPD) patients to glucocorticoids. HDAC2 expression and its role in mediating glucocorticoid effects on fibroblast functions, however, has not been fully studied. This study was designed to investigate whether HDAC2 mediates glucocorticoid effects on release of inflammatory cytokines and matrix metalloproteinases (MMPs) from human lung fibroblasts. Methods Human lung fibroblasts (HFL-1 cells) were stimulated with interleukin (IL)-1 ? plus tumor necrosis factor (TNF)-? in the presence or absence of the glucocorticoid budesonide. Cytokines (IL-6 and IL-8) were quantified by enzyme linked immunosorbent assay (ELISA) and MMPs (MMP-1 and MMP-3) by immunoblotting in culture medium. The role of HDAC2 was investigated using a pharmacologic inhibitor as well as a small interfering ribonucleic acid (siRNA) targeting HDAC2. Results We have demonstrated that budesonide concentration-dependently (10?10–10?7 M) inhibited IL-6, IL-8, MMP-1, and MMP-3 release by HFL-1 cells in response to IL-1? plus TNF-?. While an HDAC inhibitor significantly blocked the inhibitory effect of budesonide on human bronchial epithelial cells (HBECs) and monocytes (THP-1 cells), it did not block the inhibitory effect of budesonide on release of cytokines and MMPs from HFL-1 cells. Similarly, an HDAC2-siRNA blocked budesonide inhibition of cytokine release in HBECs, but it did not block the inhibitory effect of budesonide on HFL-1 cytokine and MMP release. Furthermore, budesonide significantly blocked release of cytokines and MMPs to a similar degree in normal and COPD lung fibroblasts as well as in HFL-1 cells exposed or not exposed to cigarette smoke extract. Conclusion These findings suggest that, in contrast to airway epithelial cells and monocytes/macrophages, HDAC2 is not required for budesonide to inhibit MMP and cytokine release by lung fibroblasts and this inhibitory pathway appears to be intact in cultured fibroblasts from COPD patients. These results also suggest that budesonide has the potential to modulate fibroblast-mediated tissue remodeling following airway inflammation in COPD, which is mediated via an HDAC2 independent pathway. PMID:24062615

Wang, Xingqi; Nelson, Amy; Weiler, Zachary M; Patil, Amol; Sato, Tadashi; Kanaji, Nobuhiro; Nakanishi, Masanori; Michalski, Joel; Farid, Maha; Basma, Hesham; LeVan, Tricia D; Miller-Larsson, Anna; Wieslander, Elisabet; Muller, Kai-Christian; Holz, Olaf; Magnussen, Helgo; Rabe, Klaus F; Liu, Xiangde; Rennard, Stephen I

2013-01-01

178

miR-155 targets histone deacetylase 4 (HDAC4) and impairs transcriptional activity of B-cell lymphoma 6 (BCL6) in the Eu-miR-155 transgenic mouse model  

PubMed Central

Multiple studies have established that microRNAs (miRNAs) are involved in the initiation and progression of cancer. Notably, miR-155 is one of the most overexpressed miRNAs in several solid and hematological malignancies. Ectopic miR-155 expression in mice B cells (E?-miR-155 transgenic mice) has been shown to induce pre–B-cell proliferation followed by high-grade lymphoma/leukemia. Loss of miR-155 in mice resulted in impaired immunity due to defective T-cell–mediated immune response. Here we provide a mechanistic insight into miR-155–induced leukemogenesis in the E?-miR-155 mouse model through genome-wide transcriptome analysis of naïve B cells and target studies. We found that a key transcriptional repressor and proto-oncogene, Bcl6 is significantly down-regulated in E?-miR-155 mice. The reduction of Bcl6 subsequently leads to de-repression of some of the known Bcl6 targets like inhibitor of differentiation (Id2), interleukin-6 (IL6), cMyc, Cyclin D1, and Mip1?/ccl3, all of which promote cell survival and proliferation. We show that Bcl6 is indirectly regulated by miR-155 through Mxd1/Mad1 up-regulation. Interestingly, we found that miR-155 directly targets HDAC4, a corepressor partner of BCL6. Furthermore, ectopic expression of HDAC4 in human-activated B-cell–type diffuse large B-cell lymphoma (DLBCL) cells results in reduced miR-155–induced proliferation, clonogenic potential, and increased apoptosis. Meta-analysis of the diffuse large B-cell lymphoma patient microarray data showed that miR-155 expression is inversely correlated with Bcl6 and Hdac4. Hence this study provides a better understanding of how miR-155 causes disruption of the BCL6 transcriptional machinery that leads to up-regulation of the survival and proliferation genes in miR-155–induced leukemias. PMID:23169640

Sandhu, Sukhinder K.; Volinia, Stefano; Costinean, Stefan; Galasso, Marco; Neinast, Reid; Santhanam, Ramasamy; Parthun, Mark R.; Perrotti, Danilo; Marcucci, Guido; Garzon, Ramiro; Croce, Carlo M.

2012-01-01

179

A novel series of l-2-benzyloxycarbonylamino-8-(2-pyridyl)-disulfidyloctanoic acid derivatives as histone deacetylase inhibitors: design, synthesis and molecular modeling study.  

PubMed

Histone deacetylases inhibitors (HDACIs) have become an attractive class of anticancer agents. In order to find some novel potent HDACIs, we designed and synthesized a series of l-2-benzyloxycarbonylamino-8-(2-pyridyl)-disulfidyloctanoic acid derivatives. All compounds exhibited potent HDAC-inhibitory activity, and two of them had similar potency to TSA. The introduction of 2-amino-4-phenylthiazole or 9-methyleneoxy-fluorenyl group at the surface recognize domain of these HDACIs could greatly increase their HDAC-inhibitory activity. Molecular modeling studies indicated that coordination of the zinc ion by these inhibitors, and formation of hydrogen bond and hydrophobic interaction between inhibitors and HDACs were essential for the HDAC-inhibitory activities of these inhibitors. Asp181, Asp269, Leu276 and Tyr308 in the active site of HDAC2 gave favorable contributions for binding with all compounds. PMID:22465091

Huang, Dawei; Li, Xiaohui; Wei, Yingdong; Xiu, Zhilong

2012-06-01

180

Identification of selective class II histone deacetylase inhibitors using a novel dual-parameter binding assay based on fluorescence anisotropy and lifetime.  

PubMed

Histone deacetylases (HDACs) are important epigenetic factors regulating a variety of vital cellular functions such as cell cycle progression, differentiation, cell migration, and apoptosis. Consequently, HDACs have emerged as promising targets for cancer therapy. The drugability of HDACs has been shown by the discovery of several structural classes of inhibitors (HDACis), particularly by the recent approval of two HDACis, vorinostat (ZOLINZA) and romidepsin (Istodax), for the treatment of cutaneous T-cell lymphoma by the US Food and Drug Administration. The outstanding potential of HDACis, with a defined isoform selectivity profile as drugs against a plurality of diseases, vindicates increased effort in developing high-throughput capable assays for screening campaigns. In this study, a dual-competition assay exploiting changes in fluorescence anisotropy and lifetime was used to screen the LOPAC (Sigma-Aldrich, St Louis, MO) library against the bacterial histone deacetylase homologue HDAH from Bordetella, which shares 35% identity with the second deacetylase domain of HDAC6. The binding assay proved to be highly suitable for high-throughput screening campaigns. Several LOPAC compounds have been identified to inhibit HDAH in the lower micromolar range. Most interestingly, some of the hit compounds turned out to be weak but selective inhibitors of human class IIa and IIb HDACs. PMID:22027638

Haus, Patricia; Korbus, Michael; Schröder, Michael; Meyer-Almes, Franz-Josef

2011-12-01

181

Inhibition of Class I Histone Deacetylases Unveils a Mitochondrial Signature and Enhances Oxidative Metabolism in Skeletal Muscle and Adipose Tissue  

PubMed Central

Chromatin modifications are sensitive to environmental and nutritional stimuli. Abnormalities in epigenetic regulation are associated with metabolic disorders such as obesity and diabetes that are often linked with defects in oxidative metabolism. Here, we evaluated the potential of class-specific synthetic inhibitors of histone deacetylases (HDACs), central chromatin-remodeling enzymes, to ameliorate metabolic dysfunction. Cultured myotubes and primary brown adipocytes treated with a class I–specific HDAC inhibitor showed higher expression of Pgc-1?, increased mitochondrial biogenesis, and augmented oxygen consumption. Treatment of obese diabetic mice with a class I– but not a class II–selective HDAC inhibitor enhanced oxidative metabolism in skeletal muscle and adipose tissue and promoted energy expenditure, thus reducing body weight and glucose and insulin levels. These effects can be ascribed to increased Pgc-1? action in skeletal muscle and enhanced PPAR?/PGC-1? signaling in adipose tissue. In vivo ChIP experiments indicated that inhibition of HDAC3 may account for the beneficial effect of the class I–selective HDAC inhibitor. These results suggest that class I HDAC inhibitors may provide a pharmacologic approach to treating type 2 diabetes. PMID:23069623

Galmozzi, Andrea; Mitro, Nico; Ferrari, Alessandra; Gers, Elise; Gilardi, Federica; Godio, Cristina; Cermenati, Gaia; Gualerzi, Alice; Donetti, Elena; Rotili, Dante; Valente, Sergio; Guerrini, Uliano; Caruso, Donatella; Mai, Antonello; Saez, Enrique; De Fabiani, Emma; Crestani, Maurizio

2013-01-01

182

Histone deacetylase 3 regulates smooth muscle differentiation in neural crest cells and development of the cardiac outflow tract  

PubMed Central

Rationale The development of the cardiac outflow tract (OFT) and great vessels is a complex process that involves coordinated regulation of multiple progenitor cell populations. Among these populations, neural crest cells make important contributions to OFT formation and aortic arch remodeling. While numerous signaling pathways, including Notch, have been implicated in this process, the role of epigenetics in OFT development remains largely unexplored. Objective As histone deacetylases (Hdacs) play important roles in the epigenetic regulation of mammalian development, we have investigated the function of Hdac3, a class I Hdac, during cardiac neural crest development. Methods and Results Using two neural crest drivers, Wnt1-Cre and Pax3Cre, we show that loss of Hdac3 in neural crest results in perinatal lethality and cardiovascular abnormalities, including interrupted aortic arch type B, aortic arch hypoplasia, double outlet right ventricle and ventricular septal defect. Affected embryos are deficient in aortic arch artery smooth muscle during mid-gestation, despite intact neural crest cell migration and preserved development of other cardiac and truncal neural crest derivatives. The Hdac3-dependent block in smooth muscle differentiation is cell autonomous and is associated with downregulation of the Notch ligand Jagged1, a key driver of smooth muscle differentiation in the aortic arch arteries. Conclusions These results indicate that Hdac3 plays a critical and specific regulatory role in the neural crest-derived smooth muscle lineage and in formation of the OFT. PMID:21959220

Singh, Nikhil; Trivedi, Chinmay M.; Lu, MinMin; Mullican, Shannon E.; Lazar, Mitchell A.; Epstein, Jonathan A.

2011-01-01

183

Histone deacetylase inhibitor AR42 regulates telomerase activity in human glioma cells via an Akt-dependent mechanism.  

PubMed

Epigenetic regulation via abnormal activation of histone deacetylases (HDACs) is a mechanism that leads to cancer initiation and promotion. Activation of HDACs results in transcriptional upregulation of human telomerase reverse transcriptase (hTERT) and increases telomerase activity during cellular immortalization and tumorigenesis. However, the effects of HDAC inhibitors on the transcription of hTERT vary in different cancer cells. Here, we studied the effects of a novel HDAC inhibitor, AR42, on telomerase activity in a PTEN-null U87MG glioma cell line. AR42 increased hTERT mRNA in U87MG glioma cells, but suppressed total telomerase activity in a dose-dependent manner. Further analyses suggested that AR42 decreases the phosphorylation of hTERT via an Akt-dependent mechanism. Suppression of Akt phosphorylation and telomerase activity was also observed with PI3K inhibitor LY294002 further supporting the hypothesis that Akt signaling is involved in suppression of AR42-induced inhibition of telomerase activity. Finally, ectopic expression of a constitutive active form of Akt restored telomerase activity in AR42-treated cells. Taken together, our results demonstrate that the novel HDAC inhibitor AR42 can suppress telomerase activity by inhibiting Akt-mediated hTERT phosphorylation, indicating that the PI3K/Akt pathway plays an important role in the regulation of telomerase activity in response to this HDAC inhibitor. PMID:23624506

Yang, Ya-Luen; Huang, Po-Hsien; Chiu, Hao-Chieh; Kulp, Samuel K; Chen, Ching-Shih; Kuo, Cheng-Ju; Chen, Huan-Da; Chen, Chang-Shi

2013-05-24

184

Treadmill exercise alters histone acetyltransferases and histone deacetylases activities in frontal cortices from wistar rats.  

PubMed

Studies have pointed out the relationship between neuroprotective exercise effects and epigenetic mechanisms on the hippocampus. Considering the role of frontal cortex on brain functions, we investigated the impact of different exercise protocols on enzymatic system involved with histone acetylation status, histone acetyltransferases (HATs), and histone desacetylases (HDACs) in frontal cortices from Wistar rats. Male Wistar rats aged 3 months were submitted to a single session or a daily running protocol during 2 weeks. The single session enhanced HAT activity, while the moderate daily exercise protocol reduced the HDAC activity. Our results indicate that frontal cortex is susceptible to epigenetic modulation following exercise and that both exercise protocols seem to induce a histone hyperacetylation condition in this brain area. PMID:25149076

Spindler, Christiano; Cechinel, Laura Reck; Basso, Carla; Moysés, Felipe; Bertoldi, Karine; Roesler, Rafael; Lovatel, Gisele Agustini; Rostirola Elsner, Viviane; Siqueira, Ionara Rodrigues

2014-11-01

185

Acute ?-Adrenergic Activation Triggers Nuclear Import of Histone Deacetylase 5 and Delays Gq-induced Transcriptional Activation*  

PubMed Central

During hemodynamic stress, catecholamines and neurohumoral stimuli may induce co-activation of Gq-coupled receptors and ?-adrenergic receptors (?-AR), leading to cardiac remodeling. Dynamic regulation of histone deacetylase 5 (HDAC5), a transcriptional repressor, is crucial during stress signaling due to its role in epigenetic control of fetal gene markers. Little is known about its regulation during acute and chronic ?-AR stimulation and its cross-interaction with Gq signaling in adult cardiac myocytes. Here, we evaluate the potential cross-talk between Gq-driven and ?-AR mediated signaling at the level of nucleocytoplasmic shuttling of HDAC5. We show the translocation of GFP-tagged wild type HDAC5 or mutants (S279A and S279D) in response to ?-AR or Gq agonists. Isoproterenol (ISO) or PKA activation results in strong nuclear accumulation of HDAC5 in contrast to nuclear export driven by Ca2+-calmodulin protein kinase II and protein kinase D. Moreover, nuclear accumulation of HDAC5 under acute ISO/PKA signaling is dependent on phosphorylation of Ser-279 and can block subsequent Gq-mediated nuclear HDAC5 export. Intriguingly, the attenuation of Gq-induced export is abolished after chronic PKA activation, yet nuclear HDAC5 remains elevated. Last, the effect of chronic ?-AR signaling on HDAC5 translocation was examined in adult myocytes from a rabbit model of heart failure, where ISO-induced nuclear import is ablated, but Gq-agonist mediated export is preserved. Acute ?-AR/PKA activation protects against hypertrophic signaling by delaying Gq-mediated transcriptional activation. This serves as a key physiological control switch before allowing genetic reprogramming via HDAC5 nuclear export during more severe stress, such as heart failure. PMID:23161540

Chang, Chia-Wei Jenny; Lee, Linda; Yu, David; Dao, Khanha; Bossuyt, Julie; Bers, Donald M.

2013-01-01

186

Gene expression profiling in response to the histone deacetylase inhibitor BL1521 in neuroblastoma  

SciTech Connect

Neuroblastoma is a childhood tumor with a poor survival in advanced stage disease despite intensive chemotherapeutic regimes. The new histone deacetylase (HDAC) inhibitor BL1521 has shown promising results in neuroblastoma. Inhibition of HDAC resulted in a decrease in proliferation and metabolic activity, induction of apoptosis and differentiation of neuroblastoma cells. In order to elucidate the mechanism mediating the effects of BL1521 on neuroblastoma cells, we investigated the gene expression profile of an MYCN single copy (SKNAS) and an MYCN amplified (IMR32) neuroblastoma cell line after treatment with BL1521 using the Affymetrix oligonucleotide array U133A. An altered expression of 255 genes was observed in both neuroblastoma cell lines. The majority of these genes were involved in gene expression, cellular metabolism, and cell signaling. We observed changes in the expression of vital genes belonging to the cell cycle (cyclin D1 and CDK4) and apoptosis (BNIP3, BID, and BCL2) pathway in response to BL1521. The expression of 37 genes was altered by both BL1521 and Trichostatin A, which could indicate a common gene set regulated by different HDAC inhibitors. BL1521 treatment changed the expression of a number of MYCN-associated genes. Several genes in the Wnt and the Delta/Notch pathways were changed in response to BL1521 treatment, suggesting that BL1521 is able to induce the differentiation of neuroblastoma cells into a more mature phenotype.

Ruijter, Annemieke J.M. de [Academic Medical Centre, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, PO Box 22700, 1100 DE Amsterdam (Netherlands); Meinsma, Rutger J. [Academic Medical Centre, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, PO Box 22700, 1100 DE Amsterdam (Netherlands); Bosma, Peter [Leiden Genome Technology Centre, Leiden University Medical Centre, Leiden (Netherlands); Kemp, Stephan [Academic Medical Centre, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, PO Box 22700, 1100 DE Amsterdam (Netherlands); Caron, Huib N. [Academic Medical Centre, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, PO Box 22700, 1100 DE Amsterdam (Netherlands); Kuilenburg, Andre B.P. van [Academic Medical Centre, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, PO Box 22700, 1100 DE Amsterdam (Netherlands)]. E-mail: a.b.vankuilenburg@amc.uva.nl

2005-10-01

187

Histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA)-mediated correction of ?1-antitrypsin deficiency.  

PubMed

?1-Antitrypsin (?1AT) deficiency (?1ATD) is a consequence of defective folding, trafficking, and secretion of ?1AT in response to a defect in its interaction with the endoplasmic reticulum proteostasis machineries. The most common and severe form of ?1ATD is caused by the Z-variant and is characterized by the accumulation of ?1AT polymers in the endoplasmic reticulum of the liver leading to a severe reduction (>85%) of ?1AT in the serum and its anti-protease activity in the lung. In this organ ?1AT is critical for ensuring tissue integrity by inhibiting neutrophil elastase, a protease that degrades elastin. Given the limited therapeutic options in ?1ATD, a more detailed understanding of the folding and trafficking biology governing ?1AT biogenesis and its response to small molecule regulators is required. Herein we report the correction of Z-?1AT secretion in response to treatment with the histone deacetylase (HDAC) inhibitor suberoylanilide hydroxamic acid (SAHA), acting in part through HDAC7 silencing and involving a calnexin-sensitive mechanism. SAHA-mediated correction restores Z-?1AT secretion and serpin activity to a level 50% that observed for wild-type ?1AT. These data suggest that HDAC activity can influence Z-?1AT protein traffic and that SAHA may represent a potential therapeutic approach for ?1ATD and other protein misfolding diseases. PMID:22995909

Bouchecareilh, Marion; Hutt, Darren M; Szajner, Patricia; Flotte, Terence R; Balch, William E

2012-11-01

188

Expression of histone deacetylase-1 and p300 in aristolochic acid nephropathy models.  

PubMed

Aristolochic acid nephropathy (AAN) is mainly caused by aristolochic acid I (AAI), but the actual mechanism is still uncertain. The current study explored the correlation among the expression of Smad7, p300, histone deacetylase-1 (HDAC1) and the development of AAN using transmission electron microscopy (TEM), RT-PCR, and western blotting in the AAN mouse model and in the AAN cell model. TEM revealed that the renal tubular epithelial cells from the AAI-treated mice presented organelle damages and nuclear deformation. We found that a certain dose of AAI caused renal fibrosis and induced renal tubular epithelial cells to differentiate into myofibroblasts. There was a gradual increase in the expression of HDAC1 mRNA and protein observed using RT-PCR and western blotting in the AAN cell model compared with the control group. Gradual decrease in the expression of Smad7 and p300 mRNA and protein was revealed in the AAN mouse and cell models compared with the control group. These results suggest that AAI dose dependently contributed to the development of AAN, and HDAC1 and p300 participate in the modulation of TGF-?/Smad pathway-mediated renal interstitial fibrosis. PMID:24796935

Tian, Yahui; Yang, Yaohui; Gao, Lei; Zhao, Haijiao; Peng, Xiaolan; Zhang, Zhongwen; Wu, Guojuan

2014-09-01

189

Inhibition of Histone Deacetylase Impacts Cancer Stem Cells and Induces Epithelial-Mesenchyme Transition of Head and Neck Cancer  

PubMed Central

The genome is organized and packed into the nucleus through interactions with core histone proteins. Emerging evidence suggests that tumors are highly responsive to epigenetic alterations that induce chromatin-based events and dynamically influence tumor behavior. We examined chromatin organization in head and neck squamous cell carcinoma (HNSCC) using acetylation levels of histone 3 as a marker of chromatin compaction. Compared to control oral keratinocytes, we found that HNSCC cells are hypoacetylated and that microenvironmental cues (e.g., microvasculature endothelial cells) induce tumor acetylation. Furthermore, we found that chemical inhibition of histone deacetylases (HDAC) reduces the number of cancer stem cells (CSC) and inhibits clonogenic sphere formation. Paradoxically, inhibition of HDAC also induced epithelial-mesenchymal transition (EMT) in HNSCC cells, accumulation of BMI-1, an oncogene associated with tumor aggressiveness, and expression of the vimentin mesenchymal marker. Importantly, we observed co-expression of vimentin and acetylated histone 3 at the invasion front of human HNSCC tumor tissues. Collectively, these findings suggest that environmental cues, such as endothelial cell-secreted factors, modulate tumor plasticity by limiting the population of CSC and inducing EMT. Therefore, inhibition of HDAC may constitute a novel strategy to disrupt the population of CSC in head and neck tumors to create a homogeneous population of cancer cells with biologically defined signatures and predictable behavior. PMID:23527004

Giudice, Fernanda S.; Pinto, Decio S.; Nör, Jacques E.; Squarize, Cristiane H.; Castilho, Rogerio M.

2013-01-01

190

Pitx2-dependent Occupancy by Histone Deacetylases Is Associated with T-box Gene Regulation in Mammalian Abdominal Tissue*?  

PubMed Central

The homeodomain transcription factor Pitx2 and the T-box transcription factors are essential for organogenesis. Pitx2 and T-box genes are induced by growth factors and function as transcriptional activators or repressors. Gene expression analyses on abdominal tissue were used to identify seven of the T-box genes of the genome as Pitx2 target genes in the abdomen at embryonic day.10.5. Pitx2 activated Tbx4, Tbx15, and Mga and repressed Tbx1, Tbx2, Tbx5, and Tbx6 expression. As expected, activated genes showed reduced expression patterns, and repressed T-box genes showed increased expression patterns in the abdomen of Pitx2 mutants. Pitx2 occupied chromatin sites near all of these T-box genes. Co-occupancy by coactivators, corepressors, and histone acetylation at these sites was frequently Pitx2-dependent. Genes repressed by Pitx2 generally showed increased histone acetylation and decreased histone deacetylase (HDAC)/corepressor occupancy in Pitx2 mutants. The lower N-CoR, HDAC1, and HDAC3 occupancy observed at multiple sites along Tbx1 chromatin in mutants is consistent with the model that increased histone acetylation and gene expression of Tbx1 may result from a loss of recruitment of corepressors by Pitx2. Genes activated by Pitx2 showed less consistent patterns in chromatin analyses. Reduced H4 acetylation and increased HDAC1/nuclear receptor corepressor (N-CoR) occupancy at some Tbx4 sites were accompanied by increased H3 acetylation and reduced HDAC3 occupancy at the same or other more distal chromatin sites in mutants. Pitx2-dependent occupancy by corepressors resulted in alteration of the acetylation levels of several T-box genes, whereas Pitx2-dependent occupancy by coactivators was more site-localized. These studies will provide the basic scientific underpinning to understand abdominal wall syndromes. PMID:20129917

Hilton, Traci; Gross, Michael K.; Kioussi, Chrissa

2010-01-01

191

Development of novel ferulic acid derivatives as potent histone deacetylase inhibitors.  

PubMed

Histone deacetylase inhibitors (HDACIs) offer a promising strategy for cancer therapy. The discovery of potent ferulic acid-based HDACIs with hydroxamic acid or 2-aminobenzamide group as zinc binding group was reported. The halogeno-acetanilide was introduced as novel surface recognition moiety (SRM). The majority of title compounds displayed potent HDAC inhibitory activity. In particular, FA6 and FA16 exhibited significant enzymatic inhibitory activities, with IC50 values of 3.94 and 2.82 ?M, respectively. Furthermore, these compounds showed moderate antiproliferative activity against a panel of human cancer cells. FA17 displayed promising profile as an antitumor candidate. The results indicated that these ferulic acid derivatives could serve as promising lead compounds for further optimization. PMID:24095016

Wang, Fang; Lu, Wen; Zhang, Tao; Dong, Jinyun; Gao, Hongping; Li, Pengfei; Wang, Sicen; Zhang, Jie

2013-11-15

192

Search for novel histone deacetylase inhibitors. Part II: design and synthesis of novel isoferulic acid derivatives.  

PubMed

Previously, we described the discovery of potent ferulic acid-based histone deacetylase inhibitors (HDACIs) with halogeno-acetanilide as novel surface recognition moiety (SRM). In order to improve the affinity and activity of these HDACIs, twenty seven isoferulic acid derivatives were described herein. The majority of title compounds displayed potent HDAC inhibitory activity. In particular, IF5 and IF6 exhibited significant enzymatic inhibitory activities, with IC50 values of 0.73 ± 0.08 and 0.57 ± 0.16 ?M, respectively. Furthermore, these compounds showed moderate antiproliferative activity against human cancer cells. Especially, IF6 displayed promising profile as an antitumor candidate with IC50 value of 3.91 ± 0.97 ?M against HeLa cells. The results indicated that these isoferulic acid derivatives could serve as promising lead compounds for further optimization. PMID:24702857

Lu, Wen; Wang, Fang; Zhang, Tao; Dong, Jinyun; Gao, Hongping; Su, Ping; Shi, Yaling; Zhang, Jie

2014-05-01

193

Mechanisms of G1 cell cycle arrest and apoptosis in myeloma cells induced by hybrid-compound histone deacetylase inhibitor  

SciTech Connect

Highlights: •Novel histone deacetylase inhibitor Ky-2, remarkably inhibits myeloma cell growth. •Ky-2 demonstrates no cytotoxicity against normal lymphocytic cells. •Ky-2 induces cell cycle arrest through the cell cycle-associated proteins. •Ky-2 induces Bcl-2-inhibitable apoptosis through a caspase-dependent cascade. -- Abstract: Objectives: Histone deacetylase (HDAC) inhibitors are new therapeutic agents, used to treat various types of malignant cancers. In the present study, we investigated the effects of Ky-2, a hybrid-compound HDAC inhibitor, on the growth of mouse myeloma cells. Materials and methods: Myeloma cells, HS-72, P3U1, and mouse normal cells were used in this study. Effect of HDAC inhibitors on cell viability was determined by WST-assay and trypan blue assay. Cell cycle was analyzed using flow cytometer. The expression of cell cycle regulatory and the apoptosis associated proteins were examined by Western blot analysis. Hoechst’s staining was used to detect apoptotic cells. Results: Our findings showed that Ky-2 decreased the levels of HDACs, while it enhanced acetylation of histone H3. Myeloma cell proliferation was inhibited by Ky-2 treatment. Interestingly, Ky-2 had no cytotoxic effects on mouse normal cells. Ky-2 treatment induced G1-phase cell cycle arrest and accumulation of a sub-G1 phase population, while Western blotting analysis revealed that expressions of the cell cycle-associated proteins were up-regulated. Also, Ky-2 enhanced the cleavage of caspase-9 and -3 in myeloma cells, followed by DNA fragmentation. In addition, Ky-2 was not found to induce apoptosis in bcl-2 overexpressing myeloma cells. Conclusion: These findings suggest that Ky-2 induces apoptosis via a caspase-dependent cascade and Bcl-2-inhibitable mechanism in myeloma cells.

Fujii, Seiko [Division of Infections and Molecular Biology, Kyushu Dental University (Japan) [Division of Infections and Molecular Biology, Kyushu Dental University (Japan); Division of Maxillofacial Surgery, Kyushu Dental University (Japan); Okinaga, Toshinori; Ariyoshi, Wataru [Division of Infections and Molecular Biology, Kyushu Dental University (Japan) [Division of Infections and Molecular Biology, Kyushu Dental University (Japan); Oral Biology Research Center, Kyushu Dental University (Japan); Takahashi, Osamu; Iwanaga, Kenjiro [Division of Maxillofacial Surgery, Kyushu Dental University (Japan)] [Division of Maxillofacial Surgery, Kyushu Dental University (Japan); Nishino, Norikazu [Oral Biology Research Center, Kyushu Dental University (Japan)] [Oral Biology Research Center, Kyushu Dental University (Japan); Tominaga, Kazuhiro [Division of Maxillofacial Surgery, Kyushu Dental University (Japan)] [Division of Maxillofacial Surgery, Kyushu Dental University (Japan); Nishihara, Tatsuji, E-mail: tatsujin@kyu-dent.ac.jp [Division of Infections and Molecular Biology, Kyushu Dental University (Japan) [Division of Infections and Molecular Biology, Kyushu Dental University (Japan); Oral Biology Research Center, Kyushu Dental University (Japan)

2013-05-10

194

Histone deacetylase 3 represses p15{sup INK4b} and p21{sup WAF1/cip1} transcription by interacting with Sp1  

SciTech Connect

Histone deacetylase 3 (HDAC3) has been implicated to play roles in governing cell proliferation. Here we demonstrated that the overexpression of HDAC3 repressed transcription of p15{sup INK4b} and p21{sup WAF1/cip1} genes in 293T cells, and that the recruitment of HDAC3 to the promoter regions of these genes was critical to this repression. We also showed that HDAC3 repressed GAL4-Sp1 transcriptional activity, and that Sp1 was co-immunoprecipitated with FLAG-tagged HDAC3. We conclude that HDAC3 can repress p15{sup INK4b} and p21{sup WAF1/cip1} transcription by interacting with Sp1. Furthermore, knockdown of HDAC3 by RNAi up-regulated the transcriptional expression of p15{sup INK4b}, but not that of p21{sup WAF1/cip1}, implicating the different roles of HDAC3 in repression of p15{sup INK4b} and p21{sup WAF1/cip1} transcription. Data from this study indicate that the inhibition of p15{sup INK4b} and p21{sup WAF1/cip1} may be one of the mechanisms by which HDAC3 participates in cell cycle regulation and oncogenesis.

Huang Weifeng [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Tan Dapeng [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Wang Xiuli [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Han Songyan [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Tan Jiang [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Zhao Yanmei [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Lu Jun [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China)]. E-mail: ycsuo@nenu.edu.cn; Huang Baiqu [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China)

2006-01-06

195

Inhibition of histone deacetylase-induced myocardial repair is mediated by c-kit in infarcted hearts.  

PubMed

Histone deacetylases (HDACs) play a critical role in the regulation of gene transcription, cardiac development, and diseases. The aim of this study was to test whether inhibition of HDACs induces myocardial repair and cardiac function restoration through c-kit signaling in mouse myocardial infarction models. Myocardial infarction in wild type Kit(+/+) and Kit(W)/Kit(W-v) mice was created following thoracotomy by applying permanent ligation to the left anterior descending artery. The HDAC inhibitor, trichostatin A (TSA, 0.1 mg/kg), was intraperitoneally injected daily for a consecutive 8 weeks after myocardial infarction. 5-Bromo-2-deoxyuridine (BrdU, 50 mg/kg) was intraperitoneally delivered every other day to pulse-chase label in vivo endogenous cardiac replication. Eight weeks later, inhibition of HDACs in vivo resulted in an improvement in ventricular functional recovery and the prevention of myocardial remodeling in Kit(+/+) mice, which was eliminated in Kit(W)/Kit(W-v) mice. HDAC inhibition promoted cardiac repairs and neovascularization in the infarcted myocardium, which were absent in Kit(W)/Kit(W-v) mice. Re-introduction of TSA-treated wild type c-kit(+) CSCs into Kit(W)/Kit(W-v) myocardial infarction heart restored myocardial functional improvement and cardiac repair. To further validate that HDAC inhibition stimulates c-kit(+) cardiac stem cells (CSCs) to facilitate myocardial repair, GFP(+) c-kit(+) CSCs were preconditioned with TSA (50 nmol/liter) for 24 h and re-introduced into infarcted hearts for 2 weeks. Preconditioning of c-kit(+) CSCs via HDAC inhibition with trichostatin A significantly increased c-kit(+) CSC-derived myocytes and microvessels and enhanced functional recovery in myocardial infarction hearts in vivo. Our results provide evidence that HDAC inhibition promotes myocardial repair and prevents cardiac remodeling, which is dependent upon c-kit signaling. PMID:23024362

Zhang, Ling; Chen, Bing; Zhao, Yu; Dubielecka, Patrycja M; Wei, Lei; Qin, Gang J; Chin, Y Eugene; Wang, Yigang; Zhao, Ting C

2012-11-16

196

Activating Transcription Factor 3 regulates in part the enhanced tumour cell cytotoxicity of the histone deacetylase inhibitor M344 and cisplatin in combination  

Microsoft Academic Search

BACKGROUND: Activating Transcription Factor (ATF) 3 is a key regulator of the cellular integrated stress response whose expression has also been correlated with pro-apoptotic activities in tumour cell models. Combination treatments with chemotherapeutic drugs, such as cisplatin, and histone deacetylase (HDAC) inhibitors have been demonstrated to enhance tumour cell cytotoxicity. We recently demonstrated a role for ATF3 in regulating cisplatin-induced

Carly St Germain; Anna O'Brien; Jim Dimitroulakos

2010-01-01

197

Analysis of the genomic response of human prostate cancer cells to histone deacetylase inhibitors  

PubMed Central

Histone deacetylases (HDACs) have emerged as important targets for cancer treatment. HDAC-inhibitors (HDACis) are well tolerated in patients and have been approved for the treatment of patients with cutaneous T-cell lymphoma (CTCL). To improve the clinical benefit of HDACis in solid tumors, combination strategies with HDACis could be employed. In this study, we applied Analysis of Functional Annotation (AFA) to provide a comprehensive list of genes and pathways affected upon HDACi-treatment in prostate cancer cells. This approach provides an unbiased and objective approach to high throughput data mining. By performing AFA on gene expression data from prostate cancer cell lines DU-145 (an HDACi-sensitive cell line) and PC3 (a relatively HDACi-resistant cell line) treated with HDACis valproic acid or vorinostat, we identified biological processes that are affected by HDACis and are therefore potential treatment targets for combination therapy. Our analysis revealed that HDAC-inhibition resulted among others in upregulation of major histocompatibility complex (MHC) genes and deregulation of the mitotic spindle checkpoint by downregulation of genes involved in mitosis. These findings were confirmed by AFA on publicly available data sets from HDACi-treated prostate cancer cells. In total, we analyzed 375 microarrays with HDACi treated and non-treated (control) prostate cancer cells. All results from this extensive analysis are provided as an online research source (available at the journal’s website and at http://luigimarchionni.org/HDACIs.html). By publishing this data, we aim to enhance our understanding of the cellular changes after HDAC-inhibition, and to identify novel potential combination strategies with HDACis for the treatment of prostate cancer patients. PMID:23880963

Kortenhorst, Madeleine SQ; Wissing, Michel D; Rodriguez, Ronald; Kachhap, Sushant K; Jans, Judith JM; Van der Groep, Petra; Verheul, Henk MW; Gupta, Anuj; Aiyetan, Paul O; van der Wall, Elsken; Carducci, Michael A; Van Diest, Paul J; Marchionni, Luigi

2013-01-01

198

SLC5A8 triggers tumor cell apoptosis through pyruvate-dependent inhibition of histone deacetylases.  

PubMed

Tumor cells up-regulate glycolysis but convert pyruvate into lactate instead of oxidizing it. Here, we show that pyruvate, but not lactate, is an inhibitor of histone deacetylases (HDAC) and an inducer of apoptosis in tumor cells and that SLC5A8, a Na(+)/monocarboxylate cotransporter, is obligatory for this process. We found that SLC5A8 is expressed in nontransformed breast epithelial cell lines but silenced by DNA methylation in tumor cell lines. The down-regulation of the gene is also evident in primary breast tumors. When MCF7 breast tumor cells are transfected with SLC5A8 cDNA, the cells undergo pyruvate-dependent apoptosis. Butyrate and propionate also induce apoptosis in SLC5A8-expressing cells, whereas lactate does not. The differential ability of these monocarboxylates to cause apoptosis in SLC5A8-expressing MCF7 cells correlates with their ability to inhibit HDACs. Apoptosis induced by SLC5A8/pyruvate in MCF7 cells is associated with up-regulation of p53, Bax, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), TRAIL receptor (TRAILR) 1, and TRAILR2 and down-regulation of Bcl2 and survivin. Lactate dehydrogenase isozymes are differentially expressed in nontransformed cells and tumor cells such that the latter convert pyruvate into lactate. Silencing of SLC5A8 coupled with conversion of pyruvate into lactate in tumor cells correlates with increased HDAC activity in these cells compared with nontransformed cells. Our studies thus identify pyruvate as a HDAC inhibitor and indicate that the Na(+)-coupled pyruvate transport underlies the tumor-suppressive role of SLC5A8. We propose that tumor cells silence SLC5A8 and convert pyruvate into lactate as complementary mechanisms to avoid pyruvate-induced cell death. PMID:17178845

Thangaraju, Muthusamy; Gopal, Elangovan; Martin, Pamela M; Ananth, Sudha; Smith, Sylvia B; Prasad, Puttur D; Sterneck, Esta; Ganapathy, Vadivel

2006-12-15

199

Histone deacetylase inhibition increases levels of choline kinase alpha and phosphocholine facilitating non-invasive imaging in human cancers  

PubMed Central

Histone deacetylase (HDAC) inhibitors are currently approved for cutaneous T-cell lymphoma and are in mid-late stage trials for other cancers. The HDAC inhibitors LAQ824 and SAHA increase phosphocholine (PC) levels in human colon cancer cells and tumor xenografts as observed by magnetic resonance spectroscopy (MRS). In this study, we show that belinostat, an HDAC inhibitor with an alternative chemical scaffold, also caused a rise in cellular PC content that was detectable by 1H and 31P MRS in prostate and colon carcinoma cells. In addition, 1H MRS showed an increase in branched chain amino acid and alanine concentrations. 13C-choline labeling indicated that the rise in PC resulted from increased de novo synthesis and correlated with an induction of choline kinase ? (ChoK?) expression. Furthermore, metabolic labeling experiments with 13C-glucose showed that differential glucose routing favored alanine formation at the expense of lactate production. Additional analysis revealed increases in the choline/water and phosphomonoester (including PC)/total phosphate ratios in vivo. Together, our findings provide mechanistic insights into the impact of HDAC inhibition on cancer cell metabolism and highlight PC as a candidate non-invasive imaging biomarker for monitoring the action of HDAC inhibitors. PMID:22194463

Beloueche-Babari, Mounia; Arunan, Vaitha; Troy, Helen; te Poele, Robert H; Fong, Anne-Christine Wong Te; Jackson, L Elizabeth; Payne, Geoffrey S; Griffiths, John R; Judson, Ian R; Workman, Paul; Leach, Martin O; Chung, Yuen-Li

2012-01-01

200

Highly active combination of BRD4 antagonist and histone deacetylase inhibitor against human acute myelogenous leukemia cells.  

PubMed

The bromodomain and extra-terminal (BET) protein family members, including BRD4, bind to acetylated lysines on histones and regulate the expression of important oncogenes, for example, c-MYC and BCL2. Here, we demonstrate the sensitizing effects of the histone hyperacetylation-inducing pan-histone deacetylase (HDAC) inhibitor panobinostat on human acute myelogenous leukemia (AML) blast progenitor cells (BPC) to the BET protein antagonist JQ1. Treatment with JQ1, but not its inactive enantiomer (R-JQ1), was highly lethal against AML BPCs expressing mutant NPM1c+ with or without coexpression of FLT3-ITD or AML expressing mixed lineage leukemia fusion oncoprotein. JQ1 treatment reduced binding of BRD4 and RNA polymerase II to the DNA of c-MYC and BCL2 and reduced their levels in the AML cells. Cotreatment with JQ1 and the HDAC inhibitor panobinostat synergistically induced apoptosis of the AML BPCs, but not of normal CD34(+) hematopoietic progenitor cells. This was associated with greater attenuation of c-MYC and BCL2, while increasing p21, BIM, and cleaved PARP levels in the AML BPCs. Cotreatment with JQ1 and panobinostat significantly improved the survival of the NOD/SCID mice engrafted with OCI-AML3 or MOLM13 cells (P < 0.01). These findings highlight cotreatment with a BRD4 antagonist and an HDAC inhibitor as a potentially efficacious therapy of AML. PMID:24435446

Fiskus, Warren; Sharma, Sunil; Qi, Jun; Valenta, John A; Schaub, Leasha J; Shah, Bhavin; Peth, Karissa; Portier, Bryce P; Rodriguez, Melissa; Devaraj, Santhana G T; Zhan, Ming; Sheng, Jianting; Iyer, Swaminathan P; Bradner, James E; Bhalla, Kapil N

2014-05-01

201

Effect of histone deacetylase inhibitors trichostatin A and valproic acid on hair cell regeneration in zebrafish lateral line neuromasts  

PubMed Central

In humans, auditory hair cells are not replaced when injured. Thus, cochlear hair cell loss causes progressive and permanent hearing loss. Conversely, non-mammalian vertebrates are capable of regenerating lost sensory hair cells. The zebrafish lateral line has numerous qualities that make it well-suited for studying hair cell development and regeneration. Histone deacetylase (HDAC) activity has been shown to have an important role in regenerative processes in vertebrates, but its function in hair cell regeneration in vivo is not fully understood. Here, we have examined the role of HDAC activity in hair cell regeneration in the zebrafish lateral line. We eliminated lateral line hair cells of 5-day post-fertilization larvae using neomycin and then treated the larvae with HDAC inhibitors. To assess hair cell regeneration, we used 5-bromo-2-deoxyuridine (BrdU) incorporation in zebrafish larvae to label mitotic cells after hair cell loss. We found that pharmacological inhibition of HDACs using trichostatin A (TSA) or valproic acid (VPA) increased histone acetylation in the regenerated neuromasts following neomycin-induced damage. We also showed that treatment with TSA or VPA decreased the number of supporting cells and regenerated hair cells in response to hair cell damage. Additionally, BrdU immunostaining and western blot analysis showed that TSA or VPA treatment caused a significant decrease in the percentage of S-phase cells and induced p21Cip1 and p27Kip1 expression, both of which are likely to explain the decrease in the amount of newly regenerated hair cells in treated embryos. Finally, we showed that HDAC inhibitors induced no observable cell death in neuromasts as measured by cleaved caspase-3 immunohistochemistry and western blot analysis. Taken together, our results demonstrate that HDAC activity has an important role in the regeneration of hair cells in the lateral line.

He, Yingzi; Cai, Chengfu; Tang, Dongmei; Sun, Shan; Li, Huawei

2014-01-01

202

New histone deacetylase inhibitors improve cisplatin antitumor properties against thoracic cancer cells  

PubMed Central

Histone deacetylase inhibitors (HDACi) have shown promising antitumor effects on numerous cancer cells including malignant pleural mesothelioma (MPM) and lung adenocarcinoma (ADCA) cells. However, clinical trials using these compounds alone have shown limited efficacy against solid tumors. Therefore, new molecules are being developed and combinations with classical chemotherapeutic drugs are being tested. Here, we have evaluated on three MPM and three lung ADCA cell lines the antitumor potential of four new HDACi compounds, either alone or in combination with cisplatin. These effects were compared with those of vorinostat, an HDACi approved for cancer treatments. First, we characterized the HDAC mRNA expression profiles of tumor cells and showed an increase of the classI/classII HDAC ratio. We then treated cancer cells with these new HDACi and observed a cell-death induction and an increase of HDACi target genes and proteins expression. This was particularly evident for NODH compound (pan-HDACi) which had similar effects at nanomolar concentrations as micromolar concentrations of vorinostat. Interestingly, we observed that the HDACi/cisplatin combination strongly increased cell-death and limited resistance-phenotype emergence as compared with results obtained when the drugs were used alone. These results could be exploited to develop MPM and lung ADCA treatments combining chemotherapeutic approaches. PMID:24980825

Gueugnon, Fabien; Cartron, Pierre-François; Charrier, Cedric; Bertrand, Philippe; Fonteneau, Jean-François; Gregoire, Marc; Blanquart, Christophe

2014-01-01

203

Histone deacetylase inhibitors induce apoptosis in myeloid leukemia by suppressing autophagy  

PubMed Central

Histone deacetylase (HDAC)-inhibitors (HDACis) are well characterized anti-cancer agents with promising results in clinical trials. However, mechanistically little is known regarding their selectivity in killing malignant cells while sparing normal cells. Gene expression-based chemical genomics identified HDACis as being particularly potent against Down syndrome associated myeloid leukemia (DS-AMKL) blasts. Investigating the anti-leukemic function of HDACis revealed their transcriptional and posttranslational regulation of key autophagic proteins, including ATG7. This leads to suppression of autophagy, a lysosomal degradation process that can protect cells against damaged or unnecessary organelles and protein aggregates. DS-AMKL cells exhibit low baseline autophagy due to mTOR activation. Consequently, HDAC inhibition repressed autophagy below a critical threshold, which resulted in accumulation of mitochondria, production of reactive oxygen species, DNA-damage and apoptosis. Those HDACi-mediated effects could be reverted upon autophagy activation or aggravated upon further pharmacological or genetic inhibition. Our findings were further extended to other major acute myeloid leukemia subgroups with low basal level autophagy. The constitutive suppression of autophagy due to mTOR activation represents an inherent difference between cancer and normal cells. Thus, via autophagy suppression, HDACis deprive cells of an essential pro-survival mechanism, which translates into an attractive strategy to specifically target cancer cells. PMID:24080946

Stankov, Metodi V.; Khatib, Mona El; Thakur, Basant Kumar; Heitmann, Kirsten; Panayotova-Dimitrova, Diana; Schoening, Jennifer; Bourquin, Jean-Pierre; Schweitzer, Nora; Leverkus, Martin; Welte, Karl; Reinhardt, Dirk; Li, Zhe; Orkin, Stuart H.; Behrens, Georg M.N.; Klusmann, Jan-Henning

2014-01-01

204

Histone deacetylase inhibitors and pancreatic cancer: Are there any promising clinical trials?  

PubMed Central

Pancreatic cancer, although not very frequent, has an exceptionally high mortality rate, making it one of the most common causes of cancer mortality in developed countries. Pancreatic cancer is difficult to diagnose, allowing few patients to have the necessary treatment at a relatively early stage. Despite a marginal benefit in survival, the overall response of pancreatic cancer to current systemic therapy continues to be poor, and new therapies are desperately needed. Histone deacetylase (HDAC) enzymes play an important role in the development and progression of cancer and HDAC inhibitors (HDACIs) have been shown to induce differentiation and cell cycle arrest, activate the extrinsic or intrinsic pathways of apoptosis, and inhibit invasion, migration and angiogenesis in different cancer cell lines. As a result of promising preclinical data, various HDACIs are being tested as either monotherapeutic agents or in combination regimens for both solid and hematological malignancies. Vorinostat was the first HDACI approved by the Food and Drug Administration for patients with cutaneous T-cell lymphoma. The use of HDACIs in clinical trials, in pretreated and relapsed patients suffering from advanced pancreatic cancer is discussed. Unfortunately, clinical data for HDACIs in patients with pancreatic cancer are inadequate, because only a few studies have included patients suffering from this type of neoplasm and the number of pancreatic cancer patients that entered HDACIs phase II/III trials, among others with advanced solid tumors, is very limited. More studies recruiting patients with pancreatic cancer remain to determine the efficiency of these therapies. PMID:23482354

Koutsounas, Ioannis; Giaginis, Constantinos; Theocharis, Stamatios

2013-01-01

205

Indole-3-ethylsulfamoylphenylacrylamides: potent histone deacetylase inhibitors with anti-inflammatory activity.  

PubMed

A series of 2-methyl-1H-indol-3-ethylsulfamoylphenylacrylamides based on LBH589-PXD101 core have been synthesized and evaluated for their histone deacetylase (HDAC) inhibitory and anti-inflammatory activity. In vitro, compounds 9-12 show 2.6-fold better HDAC inhibition and 3-fold better IL-6 suppression compared to LBH589·HCl (1·HCl). Furthermore, these compounds did not show apparent cell viability suppression on macrophages while in contrast, treatment with 1·HCl resulted in significant reduction in cell viability as demonstrated by an MTT assay. Repressed expression of iNOS, COX-2 and reduced phosphorylation of p65 revealed the inhibitory effect of these analogues on inflammatory mediator release which is related to inhibited NF-?B signals. (N-Hydroxy-3-{3-[2-(2-methyl-1H-indol-3-yl)-ethylsulfamoyl]-phenyl}-acrylamide) (9), exhibited ability superior to that of 1·HCl, was able to reduce carrageenan-induced acute inflammation in an animal model. Compounds 9-12 have potential anti-inflammatory activity and compound 9 can serve as lead compound for further development. PMID:25113875

Mehndiratta, Samir; Hsieh, Yi-Ling; Liu, Yi-Min; Wang, Amber Weiching; Lee, Hsueh-Yun; Liang, Lung-Yu; Kumar, Sunil; Teng, Che-Ming; Yang, Chia-Ron; Liou, Jing-Ping

2014-10-01

206

The Histone Deacetylase Inhibitor Trichostatin A Has Genotoxic Effects in Human Lymphoblasts In Vitro  

E-print Network

The Histone Deacetylase Inhibitor Trichostatin A Has Genotoxic Effects in Human Lymphoblasts not been fully identified. To explore the possibility that HDACi are genotoxic, human TK6 lymphoblastoid partially be due to this genotoxicity. Key Words: histone deacetylase inhibitor (HDACi); trichostatin A (TSA

California at Berkeley, University of

207

Combined DNA Methyltransferase and Histone Deacetylase Inhibition in the Treatment of Myeloid Neoplasms  

Microsoft Academic Search

Optimal reexpression of most genes silenced through pro- moter methylation requires the sequential application of DNA methyltransferase inhibitors followed by histone deacetylase inhibitors in tumor cell cultures. Patients with myelodys- plastic syndrome or acute myeloid leukemia (AML) were treated with the methyltransferase inhibitor 5-azacitidine (aza-CR) followed by the histone deacetylase inhibitor sodium phenylbutyrate. Major responses associated with cytogenetic complete response

Steven D. Gore; Stephen Baylin; Elizabeth Sugar; Carole B. Miller; Michael Carducci; Michael Grever; Oliver Galm; Tianna Dauses; Judith E. Karp; Michelle A. Rudek; Ming Zhao; B. Douglas Smith; Jasper Manning; Anchalee Jiemjit; George Dover; Abbie Mays; James Zwiebel; Anthony Murgo; Li-Jun Weng; James G. Herman; Medizinische Klinik; Universitaetsklinikum Aachen; Hochschule Aachen

208

Histone deacetylase inhibitors modulate the transcriptional regulation of guanylyl cyclase/natriuretic peptide receptor-a gene: interactive roles of modified histones, histone acetyltransferase, p300, AND Sp1.  

PubMed

Atrial natriuretic peptide (ANP) binds guanylyl cyclase-A/natriuretic peptide receptor-A (GC-A/NPRA) and produces the intracellular second messenger, cGMP, which regulates cardiovascular homeostasis. We sought to determine the function of histone deacetylases (HDACs) in regulating Npr1 (coding for GC-A/NPRA) gene transcription, using primary mouse mesangial cells treated with class-specific HDAC inhibitors (HDACi). Trichostatin A, a pan inhibitor, and mocetinostat (MGCD0103), a class I HDAC inhibitor, significantly enhanced Npr1 promoter activity (by 8- and 10-fold, respectively), mRNA levels (4- and 5.3-fold, respectively), and NPRA protein (2.7- and 3.5-fold, respectively). However, MC1568 (class II HDAC inhibitor) had no discernible effect. Overexpression of HDAC1 and HDAC2 significantly attenuated Npr1 promoter activity, whereas HDAC3 and HDAC8 had no effect. HDACi-treated cultured cells in vitro and intact animals in vivo showed significantly reduced binding of HDAC1 and -2 and increased accumulation of acetylated H3-K9/14 and H4-K12 at the Npr1 promoter. Deletional analyses of the Npr1 promoter along with ectopic overexpression and inhibition of Sp1 confirmed that HDACi-induced Npr1 gene transcription is accomplished by Sp1 activation. Furthermore, HDACi attenuated the interaction of Sp1 with HDAC1/2 and promoted Sp1 association with p300 and p300/cAMP-binding protein-associated factor; it also promoted the recruitment of p300 and p300/cAMP-binding protein-associated factor to the Npr1 promoter. Our results demonstrate that trichostatin A and MGCD0103 enhanced Npr1 gene expression through inhibition of HDAC1/2 and increased both acetylation of histones (H3-K9/14, H4-K12) and Sp1 by p300, and their recruitment to Npr1 promoter. Our findings define a novel epigenetic regulatory mechanism that governs Npr1 gene transcription. PMID:24451378

Kumar, Prerna; Tripathi, Satyabha; Pandey, Kailash N

2014-03-01

209

miR-326-Histone Deacetylase-3 Feedback Loop Regulates the Invasion and Tumorigenic and Angiogenic Response to Anti-cancer Drugs.  

PubMed

Histone modification is known to be associated with multidrug resistance phenotypes. Cancer cell lines that are resistant or have been made resistant to anti-cancer drugs showed lower expression levels of histone deacetylase-3 (HDAC3), among the histone deacetylase(s), than cancer cell lines that were sensitive to anti-cancer drugs. Celastrol and Taxol decreased the expression of HDAC3 in cancer cell lines sensitive to anti-cancer drugs. HDAC3 negatively regulated the invasion, migration, and anchorage-independent growth of cancer cells. HDAC3 conferred sensitivity to anti-cancer drugs in vitro and in vivo. TargetScan analysis predicted miR-326 as a negative regulator of HDAC3. ChIP assays and luciferase assays showed a negative feedback loop between HDAC3 and miR-326. miR-326 decreased the apoptotic effect of anti-cancer drugs, and the miR-326 inhibitor increased the apoptotic effect of anti-cancer drugs. miR-326 enhanced the invasion and migration potential of cancer cells. The miR-326 inhibitor negatively regulated the tumorigenic, metastatic, and angiogenic potential of anti-cancer drug-resistant cancer cells. HDAC3 showed a positive feedback loop with miRNAs such as miR-200b, miR-217, and miR-335. miR-200b, miR-217, and miR-335 negatively regulated the expression of miR-326 and the invasion and migration potential of cancer cells while enhancing the apoptotic effect of anti-cancer drugs. TargetScan analysis predicted miR-200b and miR-217 as negative regulators of cancer-associated gene, a cancer/testis antigen, which is known to regulate the response to anti-cancer drugs. HDAC3 and miR-326 acted upstream of the cancer-associated gene. Thus, we show that the miR-326-HDAC3 feedback loop can be employed as a target for the development of anti-cancer therapeutics. PMID:25138213

Kim, Youngmi; Kim, Hyuna; Park, Hyunmi; Park, Deokbum; Lee, Hansoo; Lee, Yun Sil; Choe, Jongseon; Kim, Young Myeong; Jeoung, Dooil

2014-10-01

210

Histone deacetylase 6 inhibition improves memory and reduces total tau levels in a mouse model of tau deposition  

PubMed Central

Introduction Tau pathology is associated with a number of age-related neurodegenerative disorders. Few treatments have been demonstrated to diminish the impact of tau pathology in mouse models and none are yet effective in humans. Histone deacetylase 6 (HDAC6) is an enzyme that removes acetyl groups from cytoplasmic proteins, rather than nuclear histones. Its substrates include tubulin, heat shock protein 90 and cortactin. Tubastatin A is a selective inhibitor of HDAC6. Modification of tau pathology by specific inhibition of HDAC6 presents a potential therapeutic approach in tauopathy. Methods We treated rTg4510 mouse models of tau deposition and non-transgenic mice with tubastatin (25 mg/kg) or saline (0.9%) from 5 to 7 months of age. Cognitive behavior analysis, histology and biochemical analysis were applied to access the effect of tubastatin on memory, tau pathology and neurodegeneration (hippocampal volume). Results We present data showing that tubastatin restored memory function in rTg4510 mice and reversed a hyperactivity phenotype. We further found that tubastatin reduced the levels of total tau, both histologically and by western analysis. Reduction in total tau levels was positively correlated with memory improvement in these mice. However, there was no impact on phosphorylated forms of tau, either by histology or western analysis, nor was there an impact on silver positive inclusions histologically. Conclusion Potential mechanisms by which HDAC6 inhibitors might benefit the rTg4510 mouse include stabilization of microtubules secondary to increased tubulin acetylation, increased degradation of tau secondary to increased acetylation of HSP90 or both. These data support the use of HDAC6 inhibitors as potential therapeutic agents against tau pathology. PMID:24576665

2014-01-01

211

Radiosensitizing Effect of a Phenylbutyrate-Derived Histone Deacetylase Inhibitor in Hepatocellular Carcinoma  

SciTech Connect

Purpose: Radiotherapy is integrated into the multimodal treatment of localized hepatocellular carcinoma (HCC) refractory to conventional treatment. Tumor control remains unsatisfactory and the sublethal effect associates with secondary spread. The use of an effective molecularly targeted agent in combination with radiotherapy is a potential therapeutic approach. Our aim was to assess the effect of combining a phenylbutyrate-derived histone deacetylase (HDAC) inhibitor, AR-42, with radiotherapy in in vitro and in vivo models of human HCC. Methods and Materials: Human HCC cell lines (Huh-7 and PLC-5) were used to evaluate the in vitro synergism of combining AR-42 with irradiation. Flow cytometry analyzed the cell cycle changes, whereas Western blot investigated the protein expressions after the combined treatment. Severe combined immunodeficient (SCID) mice bearing ectopic and orthotopic HCC xenografts were treated with AR-42 and/or radiotherapy for the in vivo response. Results: AR-42 significantly enhanced radiation-induced cell death by the inhibition of the DNA end-binding activity of Ku70, a highly versatile regulatory protein for DNA repair, telomere maintenance, and apoptosis. In ectopic xenografts of Huh-7 and PLC-5, pretreatment with AR-42 significantly enhanced the tumor-suppressive effect of radiotherapy by 48% and 66%, respectively. A similar combinatorial effect of AR-42 (10 and 25 mg/kg) and radiotherapy was observed in Huh-7 orthotopic model of tumor growth by 52% and 82%, respectively. This tumor suppression was associated with inhibition of intratumoral Ku70 activity as well as reductions in markers of HDAC activity and proliferation, and increased apoptosis. Conclusion: AR-42 is a potent, orally bioavailable inhibitor of HDAC with therapeutic value as a radiosensitizer of HCC.

Lu, Yen-Shen [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Department of Internal Medicine, National Taiwan University College of Medicine, Taipei, Taiwan (China); Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan (China); Chou, Chia-Hung [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Tzen, Kai-Yuan [Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan (China); Gao, Ming [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Cheng, Ann-Lii [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Department of Internal Medicine, National Taiwan University College of Medicine, Taipei, Taiwan (China); Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan (China); Graduate Institutes of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan (China); Kulp, Samuel K. [Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH (United States); Cheng, Jason Chia-Hsien, E-mail: jasoncheng@ntu.edu.tw [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan (China); Graduate Institutes of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan (China)

2012-06-01

212

The histone deacetylase inhibitor Trichostatin A modulates CD4+ T cell responses  

PubMed Central

Background Histone deacetylase inhibitors (HDACIs) induce hyperacetylation of core histones modulating chromatin structure and affecting gene expression. These compounds are also able to induce growth arrest, cell differentiation, and apoptotic cell death of tumor cells in vitro as well as in vivo. Even though several genes modulated by HDAC inhibition have been identified, those genes clearly responsible for the biological effects of these drugs have remained elusive. We investigated the pharmacological effect of the HDACI and potential anti-cancer agent Trichostatin A (TSA) on primary T cells. Methods To ascertain the effect of TSA on resting and activated T cells we used a model system where an enriched cell population consisting of primary T-cells was stimulated in vitro with immobilized anti-CD3/anti-CD28 antibodies whilst exposed to pharmacological concentrations of Trichostatin A. Results We found that this drug causes a rapid decline in cytokine expression, accumulation of cells in the G1 phase of the cell cycle, and induces apoptotic cell death. The mitochondrial respiratory chain (MRC) plays a critical role in the apoptotic response to TSA, as dissipation of mitochondrial membrane potential and reactive oxygen species (ROS) scavengers block TSA-induced T-cell death. Treatment of T cells with TSA results in the altered expression of a subset of genes involved in T cell responses, as assessed by microarray gene expression profiling. We also observed up- as well as down-regulation of various costimulatory/adhesion molecules, such as CD28 and CD154, important for T-cell function. Conclusions Taken together, our findings indicate that HDAC inhibitors have an immunomodulatory potential that may contribute to the potency and specificity of these antineoplastic compounds and might be useful in the treatment of autoimmune disorders. PMID:14606959

Moreira, Jose Manuel Afonso; Scheipers, Peter; S?rensen, Poul

2003-01-01

213

The epigenetic modifier trichostatin A, a histone deacetylase inhibitor, suppresses proliferation and epithelial-mesenchymal transition of lens epithelial cells.  

PubMed

Proliferation and epithelial-mesenchymal transition (EMT) of lens epithelium cells (LECs) may contribute to anterior subcapsular cataract (ASC) and posterior capsule opacification (PCO), which are important causes of visual impairment. Histone deacetylases (HDACs)-mediated epigenetic mechanism has a central role in controlling cell cycle regulation, cell proliferation and differentiation in a variety of cells and the pathogenesis of some diseases. However, whether HDACs are involved in the regulation of proliferation and EMT in LECs remain unknown. In this study, we evaluated the expression profile of HDAC family (18 genes) and found that class I and II HDACs were upregulated in transforming growth factor ?2 (TGF?2)-induced EMT in human LEC lines SRA01/04 and HLEB3. Tricostatin A (TSA), a class I and II HDAC inhibitor, suppressed the proliferation of LECs by G1 phase cell cycle arrest not only through inhibition of cyclin/CDK complexes and induction of p21 and p27, but also inactivation of the phosphatidylinositol-3-kinase/Akt, p38MAPK and ERK1/2 pathways. Meanwhile, TSA strongly prevented TGF?2-induced upregulation of fibronectin, collagen type I, collagen type IV, N-cadherin, Snail and Slug. We also demonstrated that the underlying mechanism of TSA affects EMT in LECs through inhibiting the canonical TGF?/Smad2 and the Jagged/Notch signaling pathways. Finally, we found that TSA completely prevented TGF?2-induced ASC in the whole lens culture semi-in vivo model. Therefore, this study may provide a new insight into the pathogenesis of ASC and PCO, and suggests that epigenetic treatment with HDAC inhibitors may be a novel therapeutic approach for the prevention and treatment of ASC, PCO and other fibrotic diseases. PMID:24157878

Chen, X; Xiao, W; Chen, W; Luo, L; Ye, S; Liu, Y

2013-01-01

214

Histone deacetylase inhibitors valproic acid and sodium butyrate enhance prostaglandins release in lipopolysaccharide-activated primary microglia.  

PubMed

Modifications of histone deacetylases (HDACs) may be involved in microglia-driven neuroinflammatory responses. Recent studies suggest that several inflammatory molecules can regulate the extent of neurodegeneration and regeneration in the central nervous system (CNS). In the present study, we investigated the effects of HDAC inhibitors (HDACi) valproic acid (VPA) and sodium butyrate (NaBut) on the release of prostaglandins (PGs) in lipopolysaccharide (LPS)-activated microglia. We found that VPA and NaBut significantly enhanced LPS-induced release of PGE2, PGD2 and 8-iso-PGF2?. In addition, both compounds increased cyclooxygenase-2 and microsomal prostaglandin E synthase immunoreactivity and gene expression in LPS-stimulated microglia. Interestingly, treatment of activated microglia with HDACi also enhanced the gene expression and the release of different pro-inflammatory cytokines. Microglia activation with LPS leads to I?B-? degradation, as well as p38, ERK1/2 and JNK MAPKs phosphorylation and thus activation, which is not affected by treatment with VPA and NaBut. Furthermore, VPA and NaBut treatment induced histone acetylation at H3-K18 in microglia. We suggest that VPA and NaBut-driven increase in PGs release in LPS-activated microglia might be regulated at the transcriptional level and involves histone hyperacetylation. Our data demonstrate that VPA and NaBut are able to modulate microglia responses to inflammatory insults and thus possibly can regulate the CNS degenerative and regenerative processes. PMID:24480366

Singh, V; Bhatia, H S; Kumar, A; de Oliveira, A C P; Fiebich, B L

2014-04-18

215

Histone deacetylase inhibitors: a novel target of anticancer therapy (review).  

PubMed

Accumulating evidence suggests that the acetylation and deacetylation of histones play significant roles in transcriptional regulation of eukaryotic cells. The balance between acetylation and deacetylation is an important factor in regulating gene expression and is thus linked to the control of cell fate. The histone deacetylase inhibitors (HDIs) including the hydroxamic acids, such as suberoylanilide hydroxamic acid and pyroxamide, the benzamides MS-275 and CI-994 and the butyrate derivative 4-PBA are a new class of anti-neoplastic agents currently being evaluated in clinical trials. Moreover, new synthetic HDIs have been used recently in phase I and II clinical trials. Over the next few years experts believe that as first generation HDIs produce clinical benefits and second generation inhibitors are rationally designed with improved specificity, this class of drugs will emerge as a new way of cancer treatment. The first clinical studies have shown that histone hyperacetylation can be achieved safely in humans and that treatment of cancer with such agents seems to become possible. The use of HDIs, probably in association with classical chemotherapy drugs or in combination with DNA-demethylating agents, could be promising for cancer patients. Further evaluation is needed to establish the clinical activity of combination therapy using HDIs with cytotoxic drugs or differentiation induced agents. PMID:16391874

Kouraklis, Gregory; Theocharis, Stamos

2006-02-01

216

Current evidence for histone deacetylase inhibitors in pancreatic cancer  

PubMed Central

Pancreatic cancer is one of the most aggressive human cancers, with more than 200?000 deaths worldwide every year. Despite recent efforts, conventional treatment approaches, such as surgery and classic chemotherapy, have only slightly improved patient outcomes. More effective and well-tolerated therapies are required to reverse the current poor prognosis of this type of neoplasm. Among new agents, histone deacetylase inhibitors (HDACIs) are now being tested. HDACIs have multiple biological effects related to acetylation of histones and many non-histone proteins that are involved in regulation of gene expression, apoptosis, cell cycle progression and angiogenesis. HDACIs induce cell cycle arrest and can activate the extrinsic and intrinsic pathways of apoptosis in different cancer cell lines. In the present review, the main mechanisms by which HDACIs act in pancreatic cancer cells in vitro, as well as their antiproliferative effects in animal models are presented. HDACIs constitute a promising treatment for pancreatic cancer with encouraging anti-tumor effects, at well-tolerated doses. PMID:23430136

Koutsounas, Ioannis; Giaginis, Constantinos; Patsouris, Efstratios; Theocharis, Stamatios

2013-01-01

217

Design and synthesis of a tetrahydroisoquinoline-based hydroxamate derivative (ZYJ-34v), an oral active histone deacetylase inhibitor with potent antitumor activity  

PubMed Central

In our previous study we developed a novel series of tetrahydroisoquinoline-based hydroxamic acid derivatives as histone deacetylase (HDAC) inhibitors (Bioorg. Med. Chem., 2010, 18, 1761–1772., J. Med. Chem., 2011, 54, 2823–2838.), among which compound ZYJ-34c (1) was identified and validated as the most potent one with marked in vitro and in vivo antitumor potency (J. Med. Chem., 2011, 54, 5532–5539.). Herein further modification of 1 afforded another oral active analogue ZYJ-34v (2) with simplified structure and lower molecular weight. Biological evaluation of compound 2 showed efficacious inhibition against HDAC1, 2, 3 and 6, which was confirmed by western blot analysis results. Most importantly, compound 2 exhibited similar even more potent in vitro and in vivo antitumor activities relative to the approved HDAC inhibitor SAHA. PMID:23581848

Zhang, Yingjie; Liu, Chunxi; Chou, C. James; Wang, Xuejian; Jia, Yuping; Xu, Wenfang

2013-01-01

218

Valproic acid and other histone deacetylase inhibitors induce microglial apoptosis and attenuate lipopolysaccharide-induced dopaminergic neurotoxicity.  

PubMed

Valproic acid (VPA), a widely prescribed drug for seizures and bipolar disorder, has been shown to be an inhibitor of histone deacetylase (HDAC). Our previous study has demonstrated that VPA pretreatment reduces lipopolysaccharide (LPS)-induced dopaminergic (DA) neurotoxicity through the inhibition of microglia over-activation. The aim of this study was to determine the mechanism underlying VPA-induced attenuation of microglia over-activation using rodent primary neuron/glia or enriched glia cultures. Other histone deacetylase inhibitors (HDACIs) were compared with VPA for their effects on microglial activity. We found that VPA induced apoptosis of microglia cells in a time- and concentration-dependent manner. VPA-treated microglial cells showed typical apoptotic hallmarks including phosphatidylserine externalization, chromatin condensation and DNA fragmentation. Further studies revealed that trichostatin A (TSA) and sodium butyrate (SB), two structurally dissimilar HDACIs, also induced microglial apoptosis. The apoptosis of microglia was accompanied by the disruption of mitochondrial membrane potential and the enhancement of acetylation levels of the histone H3 protein. Moreover, pretreatment with SB or TSA caused a robust decrease in LPS-induced pro-inflammatory responses and protected DA neurons from damage in mesencephalic neuron-glia cultures. Taken together, our results shed light on a novel mechanism whereby HDACIs induce neuroprotection and underscore the potential utility of HDACIs in preventing inflammation-related neurodegenerative disorders such as Parkinson's disease. PMID:17850978

Chen, P S; Wang, C-C; Bortner, C D; Peng, G-S; Wu, X; Pang, H; Lu, R-B; Gean, P-W; Chuang, D-M; Hong, J-S

2007-10-12

219

In vivo effects of Trichostatin A - A histone deacetylase inhibitor - On chromatin remodeling during Triturus cristatus spermatogenesis.  

PubMed

A major challenge in developmental biology field is to decipher the molecular mechanisms involved in cellular differentiation and to understand the processes that control and regulate genes expression. The study of nuclear molecular architecture during gametogenesis represents one approach toward deciphering the molecular organization and function of the eukaryotic chromatin. As spermatogenesis progresses, there is a widespread reorganization of the haploid genome followed by extensive DNA compaction. It is becoming increasingly evident that the dynamic composition of chromatin plays an important role in the activities of enzymes and in the processes that act upon it. As the information in the existing literature regarding the epigenetic modifications occurring in the advanced stages of spermatogenesis of crested newt is still scarce, we have investigated the effect of a Histone Deacetylase (HDAC) inhibitor, Trichostatin A (TSA), at the cytological level (by transmission electron microscopy - TEM, immunohistochemistry technique, fluorescence microscopy) and at the molecular level (AUT-PAGE and ChIP assay) on Triturus cristatus spermatogenesis. Our results have revealed an important role for regulation of histone deacetylase activity in controlling histone hyperacetylation and the replacement with sperm nuclear basic proteins during spermiogenesis. PMID:24100069

Burliba?a, Liliana; Zarnescu, Otilia

2013-11-01

220

Gene profile analysis of osteoblast genes differentially regulated by histone deacetylase inhibitors  

PubMed Central

Background Osteoblast differentiation requires the coordinated stepwise expression of multiple genes. Histone deacetylase inhibitors (HDIs) accelerate the osteoblast differentiation process by blocking the activity of histone deacetylases (HDACs), which alter gene expression by modifying chromatin structure. We previously demonstrated that HDIs and HDAC3 shRNAs accelerate matrix mineralization and the expression of osteoblast maturation genes (e.g. alkaline phosphatase, osteocalcin). Identifying other genes that are differentially regulated by HDIs might identify new pathways that contribute to osteoblast differentiation. Results To identify other osteoblast genes that are altered early by HDIs, we incubated MC3T3-E1 preosteoblasts with HDIs (trichostatin A, MS-275, or valproic acid) for 18 hours in osteogenic conditions. The promotion of osteoblast differentiation by HDIs in this experiment was confirmed by osteogenic assays. Gene expression profiles relative to vehicle-treated cells were assessed by microarray analysis with Affymetrix GeneChip 430 2.0 arrays. The regulation of several genes by HDIs in MC3T3-E1 cells and primary osteoblasts was verified by quantitative real-time PCR. Nine genes were differentially regulated by at least two-fold after exposure to each of the three HDIs and six were verified by PCR in osteoblasts. Four of the verified genes (solute carrier family 9 isoform 3 regulator 1 (Slc9a3r1), sorbitol dehydrogenase 1, a kinase anchor protein, and glutathione S-transferase alpha 4) were induced. Two genes (proteasome subunit, beta type 10 and adaptor-related protein complex AP-4 sigma 1) were suppressed. We also identified eight growth factors and growth factor receptor genes that are significantly altered by each of the HDIs, including Frizzled related proteins 1 and 4, which modulate the Wnt signaling pathway. Conclusion This study identifies osteoblast genes that are regulated early by HDIs and indicates pathways that might promote osteoblast maturation following HDI exposure. One gene whose upregulation following HDI treatment is consistent with this notion is Slc9a3r1. Also known as NHERF1, Slc9a3r1 is required for optimal bone density. Similarly, the regulation of Wnt receptor genes indicates that this crucial pathway in osteoblast development is also affected by HDIs. These data support the hypothesis that HDIs regulate the expression of genes that promote osteoblast differentiation and maturation. PMID:17925016

Schroeder, Tania M; Nair, Aswathy K; Staggs, Rodney; Lamblin, Anne-Francoise; Westendorf, Jennifer J

2007-01-01

221

Synergistic enhancement of NK cell-mediated cytotoxicity by combination of histone deacetylase inhibitor and ionizing radiation  

PubMed Central

Background The overexpression of histone deacetylase (HDAC) and a subsequent decrease in the acetylation levels of nuclear histones are frequently observed in cancer cells. Generally it was accepted that the deacetylation of histones suppressed expression of the attached genes. Therefore, it has been suggested that HDAC might contribute to the survival of cancer cells by altering the NKG2D ligands transcripts. By the way, the translational regulation of NKG2D ligands remaines unclear in cancer cells. It appears the modulation of this unclear mechanism could enhance NKG2D ligand expressions and the susceptibility of cancer cells to NK cells. Previously, it was reported that irradiation can increase the surface expressions of NKG2D ligands on several cancer cell types without increasing the levels of NKG2D ligand transcripts via ataxia telangiectasia mutated and ataxia telangiectasia and Rad3 related (ATM-ATR) pathway, and suggested that radiation therapy might be used to increase the translation of NKG2D ligands. Methods Two NSCLC cell lines, that is, A549 and NCI-H23 cells, were used to investigate the combined effects of ionizing radiation and HDAC inhibitors on the expressions of five NKG2D ligands. The mRNA expressions of the NKG2D ligands were quantitated by multiplex reverse transcription-PCR. Surface protein expressions were measured by flow cytometry, and the susceptibilities of cancer cells to NK cells were assayed by time-resolved fluorometry using the DELFIA® EuTDA cytotoxicity kit and by flow cytometry. Results The expressions of NKG2D ligands were found to be regulated at the transcription and translation levels. Ionizing radiation and HDAC inhibitors in combination synergistically increased the expressions of NKG2D ligands. Furthermore, treatment with ATM-ATR inhibitors efficiently blocked the increased translations of NKG2D ligands induced by ionizing radiation but did not block the increased ligand translations induced by HDAC inhibitors. The study confirms that increased NKG2D ligand levels by ionizing radiation and HDAC inhibitors could synergistically enhance the susceptibilities of cancer cells to NK-92 cells. Conclusions This study suggests that the expressions of NKG2D ligands are regulated in a complex manner at the multilevel of gene expression, and that their expressions can be induced by combinatorial treatments in lung cancer cells. PMID:24512718

2014-01-01

222

Brazilin induces apoptosis and G2/M arrest via inactivation of histone deacetylase in multiple myeloma U266 cells.  

PubMed

Although brazilin [7,11b-dihydrobenz(b)indeno[1,2-d]pyran-3,6a,9,10(6H)-tetrol] isolated from Caesalpinia sappan was known to have various biological activities, including anti-inflammation, antibacteria, and antiplatelet aggregation, there is no report yet on its anticancer activity. In the present study, the anticancer mechanism of brazilin was elucidated in human multiple myeloma U266 cells. We found that brazilin significantly inhibited the activity of histone deacetylases (HDACs), transcription factors involved in the regulation of apoptosis and cell cycle arrest in U266 cells. Consistently, brazilin enhanced acetylation of histone H3 at Lys 23, indicating activation of histone acetyltransferase (HAT), and also suppressed the expressions of HDAC1 and HDAC2 at both protein and mRNA levels. Additionally, brazilin significantly increased the number of sub-G1 cell population and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells undergoing apoptosis and also activated caspase-3 and regulated the expression of Bcl-2 family proteins, including Bax, Bcl-x(L), and Bcl-2 in U266 cells, indicating that brazilin induces apoptosis through the mitochondria-dependent pathway. Interestingly, cell cycle analysis revealed that brazilin induced G2/M phase arrest along with apoptosis induction. Consistently, brazilin attenuated the expression of cyclin-dependent kinases (CDKs), such as cyclin D1, cyclin B1, and cyclin E, and also activated p21 and p27 in U266 cells. Furthermore, HAT inhibitor anacardic acid reversed activation of acetyl-histone H3 and cleavage of PARP induced by brazilin, while pan-caspase inhibitor Z-VAD-FMK001 did not affect the expression of HDAC induced by brazilin that brazilin mediates apoptosis via inactivation of HDAC in U266 cells. Notably, brazilin significantly potentiated the cytotoxic effect of standard chemotherapeutic agents, such as bortezomib or doxorubicin, in U266 cells. When our findings are taken together, they suggest that brazilin has potential as a chemotherapeutic agent alone or in combination with an anticancer agent for multiple myeloma treatment. PMID:22967175

Kim, Bonglee; Kim, Sun-Hee; Jeong, Soo-Jin; Sohn, Eun Jung; Jung, Ji Hoon; Lee, Min Ho; Kim, Sung-Hoon

2012-10-01

223

The histone deacetylase inhibitor sodium butyrate modulates acquisition and extinction of cocaine-induced conditioned place preference  

PubMed Central

Despite decades of research on treatments for cocaine dependence, relapse rates following many behavioral and drug-based therapies remain high. This may be in part because cocaine-associated cues and contexts can invoke powerful drug cravings years after quitting. Recent studies suggest that drugs that promote cognitive function can enhance the formation of memories involving cocaine and other substances. One target of these drugs is facilitating histone acetylation to promote learning by increasing gene transcription that supports memory formation. Here, we investigate the effects of the histone deacetylase (HDAC) inhibitor sodium butyrate (NaBut) on cocaine-induced conditioned place preference (CPP) in C57BL/6 mice. After establishing a graded dose-response curve (2, 5, & 20 mg/kg) for cocaine-induced CPP, we examined the effects of different doses of NaBut (0, 0.3, 0.6, & 1.2 g/kg) on conditioning, extinction, and post-extinction reconditioning of CPP. A high dose of NaBut (1.2 g/kg) enhanced initial acquisition of cocaine CPP, but there were no effects of NaBut on reconditioning of extinguished CPP. Effects of NaBut on extinction were more complex, with a low-dose (0.3 g/kg) facilitating extinction and a high dose (1.2 g/kg) weakening extinction evident by preference at a retention test. These findings suggest that HDAC inhibition may have dose dependent effects on different components of cocaine CPP, with implications for (1) involvement of histone acetylation in context-drug learning, (2) interpretation of acute and chronic drug effects, and (3) the targeting of different types of learning in therapeutic application of HDAC inhibitors. PMID:23454534

Raybuck, Jonathan D.; McCleery, Ellen J.; Cunningham, Christopher L.; Wood, Marcelo A.; Lattal, K. Matthew

2013-01-01

224

HDAC3 acts as a negative regulator of angiogenesis  

PubMed Central

Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis. [BMB Reports 2014; 47(4): 227-232] PMID:24286308

Park, Deokbum; Park, Hyunmi; Kim, Youngmi; Kim, Hyuna; Jeoung, Dooil

2014-01-01

225

Histone Deacetylase Inhibitors Impair the Elimination of HIV-Infected Cells by Cytotoxic T-Lymphocytes  

E-print Network

Resting memory CD4[superscript +] T-cells harboring latent HIV proviruses represent a critical barrier to viral eradication. Histone deacetylase inhibitors (HDACis), such as suberanilohydroxamic acid (SAHA), romidepsin, ...

Jones, Richard Bradley

226

Histone deacetylase inhibitor induces the expression of select epithelial genes in mouse utricle sensory epithelia-derived progenitor cells.  

PubMed

Mouse utricle sensory epithelial cell-derived progenitor cells (MUCs), which have hair cell progenitor and mesenchymal features via epithelial-to-mesenchymal transition (EMT) as previously described, provide a potential approach for hair cell regeneration via cell transplantation. In this study, we treated MUCs with trichostatin A (TSA) to determine whether histone deacetylase inhibitor is able to stimulate the expression of epithelial genes in MUCs, an essential step for guiding mesenchymal-like MUCs to become sensory epithelial cells. After 72 h of TSA treatment, MUCs acquired epithelial-like features, which were indicated by increased expression of epithelial markers such as Cdh1, Krt18, and Dsp. Additionally, TSA decreased the expression of mesenchymal markers, including Zeb1, Zeb2, Snai1, and Snai2, and prosensory genes Lfng, Six1, and Dlx5. Moreover, the expression of the hair cell genes Atoh1 and Myo6 was increased in TSA-treated MUCs. We also observed significantly decreased expression of Hdac2 and Hdac3 in TSA-treated MUCs. However, no remarkable change was detected in protein expression using immunofluorescence, indicating that TSA-induced HDAC inhibition may contribute to the initial stage of the mesenchymal-to-epithelial phenotypic change. In the future, more work is needed to induce hair cell regeneration using inner ear tissue-derived progenitors to achieve an entire mesenchymal-to-epithelial transition. PMID:24945595

Hu, Zhengqing; Wang, Jue

2014-08-01

227

The effects of the histone deacetylase inhibitor 4-phenylbutyrate on gap junction conductance and permeability.  

PubMed

Longitudinal resistance is a key factor in determining cardiac action potential propagation. Action potential conduction velocity has been shown to be proportional to the square root of longitudinal resistance. A major determinant of longitudinal resistance in myocardium is the gap junction channel, comprised connexin proteins. Within the ventricular myocardium connexin43 (Cx43) is the dominantly expressed connexin. Reduced numbers of gap junction channels will result in an increase in longitudinal resistance creating the possibility of slowed conduction velocity while increased numbers of channels would potentially result in an increase in conduction velocity. We sought to determine if inhibition of histone deacetylase (HDAC) by 4-phenylbutyrate (4-PB), a known inhibitor of HDAC resulted in an increase in junctional conductance and permeability, which is not the result of changes in single channel unitary conductance. These experiments were performed using HEK-293 cells and HeLa cells stably transfected with Cx43. Following treatment with increasing concentrations of 4-PB up-regulation of Cx43 was observed via Western blot analysis. Junctional (g j) conductance and unitary single channel conductance were measured via whole-cell patch clamp. In addition intercellular transfer of lucifer yellow (LY) was determined by fluorescence microscopy. The data in this study indicate that 4-PB is able to enhance functional Cx43 gap junction coupling as indicated by LY dye transfer and multichannel and single channel data along with Western blot analysis. As a corollary, pharmacological agents such as 4-PB have the potential, by increasing intercellular coupling, to reduce the effect of ischemia. It remains to be seen whether drugs like 4-PB will be effective in preventing cardiac maladies. PMID:24027526

Kaufman, Joshua; Gordon, Chris; Bergamaschi, Roberto; Wang, Hong Z; Cohen, Ira S; Valiunas, Virginijus; Brink, Peter R

2013-01-01

228

Histone deacetylase inhibitors control the transcription and alternative splicing of prohibitin in thyroid tumor cells.  

PubMed

Prohibitin (PHB) is a ubiquitous protein with a number of different molecular functions. PHB is involved in tumorigenesis by exerting either a permissive or blocking action on tumor growth, depending on the cell context. In the present study, we investigated the effects of the histone deacetylase inhibitors (HDACis), trichostatin A (TSA) and sodium butyrate (NaB), on PHB expression in the thyroid tumor cell lines, TPC-1 and FRO. Both TSA and NaB increased PHB mRNA levels. Transfection experiments showed that the overexpression of HDAC1 or 2, but not 3, inhibited PHB promoter activity. The effects of TSA and NaB on the two major PHB mRNA splicing isoforms, were also investigated. Both TSA and NaB decreased the mRNA levels of the shorter isoform, but increased those of the longer isoform. Only the latter isoform contains a 3'UTR, which has been reported to exert a growth suppressive action. Thus, our data demonstrate that HDACis control both PHB transcription and alternative splicing. The effect of HDACis on PHB alternative splicing was not due to the modification of the expression of the ASF/SF2 splicing factor. PMID:21152868

Puppin, Cinzia; Passon, Nadia; Franzoni, Alessandra; Russo, Diego; Damante, Giuseppe

2011-02-01

229

A single allele of Hdac2 but not Hdac1 is sufficient for normal mouse brain development in the absence of its paralog.  

PubMed

The histone deacetylases HDAC1 and HDAC2 are crucial regulators of chromatin structure and gene expression, thereby controlling important developmental processes. In the mouse brain, HDAC1 and HDAC2 exhibit different developmental stage- and lineage-specific expression patterns. To examine the individual contribution of these deacetylases during brain development, we deleted different combinations of Hdac1 and Hdac2 alleles in neural cells. Ablation of Hdac1 or Hdac2 by Nestin-Cre had no obvious consequences on brain development and architecture owing to compensation by the paralog. By contrast, combined deletion of Hdac1 and Hdac2 resulted in impaired chromatin structure, DNA damage, apoptosis and embryonic lethality. To dissect the individual roles of HDAC1 and HDAC2, we expressed single alleles of either Hdac1 or Hdac2 in the absence of the respective paralog in neural cells. The DNA-damage phenotype observed in double knockout brains was prevented by expression of a single allele of either Hdac1 or Hdac2. Strikingly, Hdac1(-/-)Hdac2(+/-) brains showed normal development and no obvious phenotype, whereas Hdac1(+/-)Hdac2(-/-) mice displayed impaired brain development and perinatal lethality. Hdac1(+/-)Hdac2(-/-) neural precursor cells showed reduced proliferation and premature differentiation mediated by overexpression of protein kinase C, delta, which is a direct target of HDAC2. Importantly, chemical inhibition or knockdown of protein kinase C delta was sufficient to rescue the phenotype of neural progenitor cells in vitro. Our data indicate that HDAC1 and HDAC2 have a common function in maintaining proper chromatin structures and show that HDAC2 has a unique role by controlling the fate of neural progenitors during normal brain development. PMID:24449838

Hagelkruys, Astrid; Lagger, Sabine; Krahmer, Julia; Leopoldi, Alexandra; Artaker, Matthias; Pusch, Oliver; Zezula, Jürgen; Weissmann, Simon; Xie, Yunli; Schöfer, Christian; Schlederer, Michaela; Brosch, Gerald; Matthias, Patrick; Selfridge, Jim; Lassmann, Hans; Knoblich, Jürgen A; Seiser, Christian

2014-02-01

230

HDAC inhibitors in cancer biology: emerging mechanisms and clinical applications  

Microsoft Academic Search

Reversible acetylation mediated by histone deacetylases (HDACs) influences a broad repertoire of physiological processes, many of which are aberrantly controlled in tumor cells. As HDAC inhibition prompts tumor cells to enter apoptosis, small-molecule HDAC inhibitors have been developed as a new class of mechanism-based anti-cancer agent, many of which have entered clinical trials. Although the clinical picture is evolving and

Omar Khan; Nicholas B La Thangue; NB La Thangue

2012-01-01

231

Evaluation of novel histone deacetylase inhibitors as therapeutic agents for colorectal adenocarcinomas compared to established regimens with the histoculture drug response assay  

Microsoft Academic Search

Background and aims  This study was to evaluate the efficacy of histone deacetylase (HDAC) inhibitors in colorectal cancer together with other\\u000a established regimens.\\u000a \\u000a \\u000a \\u000a Materials and methods  Chemosensitivities of 114 colorectal cancer patients to established regimens (fluorouracil (5-FU with leucovorin (FL), capecitabine,\\u000a FL with irinotecan (FLIRI), and FL with oxaliplatin (FLOX)) as well as five hydroxamic acid derivatives (suberoylanilide hydroxamic\\u000a acid, PXD101, and

Jin C. Kim; Dae D. Kim; Yoo M. Lee; Tae W. Kim; Dong H. Cho; Moon B. Kim; Seong G. Ro; Seon Y. Kim; Yong S. Kim; Jung S. Lee

2009-01-01

232

Low-level laser therapy suppresses the oxidative stress-induced glucocorticoids resistance in U937 cells: relevance to cytokine secretion and histone deacetylase in alveolar macrophages.  

PubMed

Oxidative stress is present in severe asthma and contributes to the low response to corticoids through the downregulation of histone deacetylase (HDAC) and the increase of cytokines. Low-level laser therapy (LLLT) has been proven to be an anti-inflammatory. Thus, we investigated the laser effect on lipopolysaccharide (LPS)-induced cytokine secretion and HDAC activity in U937 cells under oxidative stress. U937 cells activated with oxidative stress were treated with dexamethasone (dexa) or laser. Cytokines and phosphoinositide 3-kinase (PI3K) were measured by ELISA whilst the HDAC was detected through colorimetric assay. LPS activated- U937 cells cytokines secretion increased with H2O2 (hydrogen peroxide) as well as with TSA (trichostatin). The HDAC activity in activated U937 cells was decreased. LLLT and dexa inhibited the LPS-stimulated U937 cells cytokines, but dexa effect disappeared with H2O2. With TSA, the LLLT was less effective on H2O2/LPS stimulated- U937 cells cytokines. Dexa failed on H2O2/LPS- induced HDAC, while LLLT restored the HDAC and the dexa effect. LLLT plus prostaglandin E2 (PGE2) increased cyclic adenosine monophosphate (cAMP) and potentiated the laser action on oxidative stress-induced cytokine. LLLT reduced the PI3K and its effects on cytokine and HDAC was suppressed with LY294002. In situations of corticoid resistance, LLLT acts decreasing the cytokines and HDAC through the activation of the protein kinase A via the inhibition of PI3K. PMID:24419178

Souza, N H C; Marcondes, P T; Albertini, R; Mesquita-Ferrari, R A; Fernandes, K P S; Aimbire, F

2014-01-01

233

Downregulation of Ca2+-Activated Cl- Channel TMEM16A by the Inhibition of Histone Deacetylase in TMEM16A-Expressing Cancer Cells.  

PubMed

The Ca(2+)-activated Cl(-) channel transmembrane proteins with unknown function 16 A (TMEM16A; also known as anoctamin 1 or discovered on gastrointestinal stromal tumor 1) plays an important role in facilitating the cell growth and metastasis of TMEM16A-expressing cancer cells. Histone deacetylase (HDAC) inhibitors (HDACi) are useful agents for cancer therapy, but it remains unclear whether ion channels are epigenetically regulated by them. Using real-time polymerase chain reaction, Western blot analysis, and whole-cell patch-clamp assays, we found a significant decrease in TMEM16A expression and its functional activity was induced by the vorinostat, a pan-HDACi in TMEM16A-expressing human cancer cell lines, the prostatic cancer cell line PC-3, and the breast cancer cell line YMB-1. TMEM16A downregulation was not induced by the chemotherapy drug paclitaxel in either cell type. Pharmacologic blockade of HDAC3 by 1 ?M T247 [N-(2-aminophenyl)-4-[1-(2-thiophen-3-ylethyl)-1H-[1],[2],[3]triazol-4-yl]benzamide], a HDAC3-selective HDACi, elicited a large decrease in TMEM16A expression and functional activity in both cell types, and pharmacologic blockade of HDAC2 by AATB [4-(acetylamino)-N-[2-amino-5-(2-thienyl)phenyl]-benzamide; 300 nM] elicited partial inhibition of TMEM16A expression (?40%) in both. Pharmacologic blockade of HDAC1 or HDAC6 did not elicit any significant change in TMEM16A expression, respectively. In addition, inhibition of HDAC3 induced by small interfering RNA elicited a large decrease in TMEM16A transcripts in both cell types. Taken together, in malignancies with a frequent gene amplification of TMEM16A, HDAC3 inhibition may exert suppressive effects on cancer cell viability via downregulation of TMEM16A. PMID:25232193

Matsuba, Sayo; Niwa, Satomi; Muraki, Katsuhiko; Kanatsuka, Saki; Nakazono, Yurika; Hatano, Noriyuki; Fujii, Masanori; Zhan, Peng; Suzuki, Takayoshi; Ohya, Susumu

2014-12-01

234

RBP1 Recruits the mSIN3Histone Deacetylase Complex to the Pocket of Retinoblastoma Tumor Suppressor Family Proteins Found in Limited Discrete Regions of the Nucleus at Growth Arrest  

Microsoft Academic Search

Retinoblastoma (RB) tumor suppressor family pocket proteins induce cell cycle arrest by repressing tran- scription of E2F-regulated genes through both histone deacetylase (HDAC)-dependent and -independent mechanisms. In this study we have identified a stable complex that accounts for the recruitment of both repression activities to the pocket. One component of this complex is RBP1, a known pocket-binding protein that exhibits

ALBERT LAI; BRIAN K. KENNEDY; DAVID A. BARBIE; NICHOLAS R. BERTOS; XIANG JIAO YANG; MARIE-CHRISTINE THEBERGE; SHIH-CHANG TSAI; EDWARD SETO; YI ZHANG; ANDREI KUZMICHEV; DANNY REINBERG; ED HARLOW; PHILIP E. BRANTON

2001-01-01

235

Histone deacetylase inhibitor valproic acid inhibits cancer cell proliferation via down-regulation of the alzheimer amyloid precursor protein.  

PubMed

The beta-amyloid precursor protein (APP) represents a type I transmembrane glycoprotein that is ubiquitously expressed. In the brain, it is a key player in the molecular pathogenesis of Alzheimer disease. Its physiological function is however less well understood. Previous studies showed that APP is up-regulated in prostate, colon, pancreatic tumor, and oral squamous cell carcinoma. In this study, we show that APP has an essential role in growth control of pancreatic and colon cancer. Abundant APP staining was found in human pancreatic adenocarcinoma and colon cancer tissue. Interestingly, treating pancreatic and colon cancer cells with valproic acid (VPA, 2-propylpentanoic acid), a known histone deacetylase (HDAC) inhibitor, leads to up-regulation of GRP78, an endoplasmic reticulum chaperone immunoglobulin-binding protein. GRP78 is involved in APP maturation and inhibition of tumor cell growth by down-regulation of APP and secreted soluble APPalpha. Trichostatin A, a pan-HDAC inhibitor, also lowered APP and increased GRP78 levels. In contrast, treating cells with valpromide, a VPA derivative lacking HDAC inhibitory properties, had no effect on APP levels. VPA did not modify the level of epidermal growth factor receptor, another type I transmembrane protein, and APLP2, a member of the APP family, demonstrating the specificity of the VPA effect on APP. Small interfering RNA-mediated knockdown of APP also resulted in significantly decreased cell growth. Based on these observations, the data suggest that APP down-regulation via HDAC inhibition provides a novel mechanism for pancreatic and colon cancer therapy. PMID:20145244

Venkataramani, Vivek; Rossner, Christian; Iffland, Lara; Schweyer, Stefan; Tamboli, Irfan Y; Walter, Jochen; Wirths, Oliver; Bayer, Thomas A

2010-04-01

236

Targeting of N-CoR and histone deacetylase 3 by the oncoprotein v-erbA yields a chromatin infrastructure-dependent transcriptional repression pathway.  

PubMed

Transcriptional repression by nuclear hormone receptors is thought to result from a unison of targeting chromatin modification and disabling the basal transcriptional machinery. We used Xenopus oocytes to compare silencing effected by the thyroid hormone receptor (TR) and its mutated version, the oncoprotein v-ErbA, on partly and fully chromatinized TR-responsive templates in vivo. Repression by v-ErbA was not as efficient as that mediated by TR, was significantly more sensitive to histone deacetylase (HDAC) inhibitor treatment and, unlike TR, v-ErbA required mature chromatin to effect repression. We find that both v-ErbA and TR can recruit the corepressor N-CoR, but, in contrast to existing models, show a concomitant enrichment for HDAC3 that occurs without an association with Sin3, HDAC1/RPD3, Mi-2 or HDAC5. We propose a requirement for chromatin infrastructure in N-CoR/HDAC3-effected repression and suggest that the inability of v-ErbA to silence on partly chromatinized templates may stem from its impaired capacity to interfere with basal transcriptional machinery function. In support of this notion, we find v-ErbA to be less competent than TR for binding to TFIIB in vitro and in vivo. PMID:10921888

Urnov, F D; Yee, J; Sachs, L; Collingwood, T N; Bauer, A; Beug, H; Shi, Y B; Wolffe, A P

2000-08-01

237

Noninvasive Magnetic Resonance Spectroscopic Pharmacodynamic Markers of a Novel Histone Deacetylase Inhibitor, LAQ824, in Human Colon Carcinoma Cells and Xenografts1  

PubMed Central

The aim of this work was to use phosphorus magnetic resonance spectroscopy (31P MRS) to investigate the pharmacodynamic effects of LAQ824, a histone deacetylase (HDAC) inhibitor. Human HT29 colon carcinoma cells were examined by 31P MRS after treatment with LAQ824 and another HDAC inhibitor, suberoylanilide hydroxamic acid. HT29 xenografts and tumor extracts were also examined using 31P MRS, pre- and post-LAQ824 treatment. Histone H3 acetylation was determined using Western blot analysis, and tumor microvessel density by immunohistochemical staining of CD31. Phosphocholine showed a significant increase in HT29 cells after treatment with LAQ824 and suberoylanilide hydroxamic acid. In vivo, the ratio of phosphomonoester/total phosphorus (TotP) signal was significantly increased in LAQ824-treated HT29 xenografts, and this ratio was inversely correlated with changes in tumor volume. Statistically significant decreases in intracellular pH, ?-nucleoside triphosphate (?-NTP)/TotP, and ?-NTP/inorganic phosphate (Pi) and an increase in Pi/TotP were also seen in LAQ824-treated tumors. Tumor extracts showed many significant metabolic changes after LAQ824 treatment, in parallel with increased histone acetylation and decreased microvessel density. Treatment with LAQ824 resulted in altered phospholipid metabolism and compromised tumor bioenergetics. The phosphocholine and phosphomonoester increases may have the potential to act as pharmacodynamic markers for noninvasively monitoring tumor response after treatment with LAQ824 or other HDAC inhibitors. PMID:18392140

Chung, Yuen-Li; Troy, Helen; Kristeleit, Rebecca; Aherne, Wynne; Jackson, L Elizabeth; Atadja, Peter; Griffiths, John R; Judson, Ian R; Workman, Paul; Leach, Martin O; Beloueche-Babari, Mounia

2008-01-01

238

Histone deacetylase inhibitors as a potential therapeutic agent for human cancer treatment  

Microsoft Academic Search

Recent evidence pointed that remodeling of the chromatin template by inhibition of the enzyme histone deacetylase could be\\u000a a promising approach for the treatment of human cancer. Alterations in histone acetylation may lead to changes in chromatin\\u000a structure and transcriptional dysregulation of genes that are implicated in controlling cell cycle progression or pathways\\u000a regulating cell differentiation and apoptosis. The histone

G. Kouraklis; E. P. Misiakos; S. Theocharis

2006-01-01

239

Unspliced X-box-binding Protein 1 (XBP1) Protects Endothelial Cells from Oxidative Stress through Interaction with Histone Deacetylase 3*  

PubMed Central

It is well known that atherosclerosis occurs geographically at branch points where disturbed flow predisposes to the development of plaque via triggering of oxidative stress and inflammatory reactions. In this study, we found that disturbed flow activated anti-oxidative reactions via up-regulating heme oxygenase 1 (HO-1) in an X-box-binding protein 1 (XBP1) and histone deacetylase 3 (HDAC3)-dependent manner. Disturbed flow concomitantly up-regulated the unspliced XBP1 (XBP1u) and HDAC3 in a VEGF receptor and PI3K/Akt-dependent manner. The presence of XBP1 was essential for the up-regulation of HDAC3 protein. Overexpression of XBP1u and/or HDAC3 activated Akt1 phosphorylation, Nrf2 protein stabilization and nuclear translocation, and HO-1 expression. Knockdown of XBP1u decreased the basal level and disturbed flow-induced Akt1 phosphorylation, Nrf2 stabilization, and HO-1 expression. Knockdown of HDAC3 ablated XBP1u-mediated effects. The mammalian target of rapamycin complex 2 (mTORC2) inhibitor, AZD2014, ablated XBP1u or HDAC3 or disturbed flow-mediated Akt1 phosphorylation, Nrf2 nuclear translocation, and HO-1 expression. Neither actinomycin D nor cycloheximide affected disturbed flow-induced up-regulation of Nrf2 protein. Knockdown of Nrf2 abolished XBP1u or HDAC3 or disturbed flow-induced HO-1 up-regulation. Co-immunoprecipitation assays demonstrated that XBP1u physically bound to HDAC3 and Akt1. The region of amino acids 201 to 323 of the HDAC3 protein was responsible for the binding to XBP1u. Double immunofluorescence staining revealed that the interactions between Akt1 and mTORC2, Akt1 and HDAC3, Akt1 and XBP1u, HDAC3, and XBP1u occurred in the cytosol. Thus, we demonstrate that XBP1u and HDAC3 exert a protective effect on disturbed flow-induced oxidative stress via up-regulation of mTORC2-dependent Akt1 phosphorylation and Nrf2-mediated HO-1 expression. PMID:25190803

Martin, Daniel; Li, Yi; Yang, Junyao; Wang, Gang; Margariti, Andriana; Jiang, Zhixin; Yu, Hui; Zampetaki, Anna; Hu, Yanhua; Xu, Qingbo; Zeng, Lingfang

2014-01-01

240

Induction of DARPP-32 by Brain-Derived Neurotrophic Factor in Striatal Neurons In Vitro Is Modified by Histone Deacetylase Inhibitors and Nab2  

PubMed Central

Neurotrophins and modifiers of chromatin acetylation and deacetylation participate in regulation of transcription during neuronal maturation and maintenance. The striatal medium spiny neuron is supported by cortically-derived brain derived neurotrophic factor and is the most vulnerable neuron in Huntington’s disease, in which growth factor and histone deacetylase activity are both disrupted. We examined the ability of three histone deacetylase inhibitors, trichostatin A, valproic acid and Compound 4 b, alone and combined with brain derived neurotrophic factor (BDNF), to promote phenotypic maturation of striatal medium spiny neurons in vitro. Exposure of these neurons to each of the three compounds led to an increase in overall histone H3 and H4 acetylation, dopamine and cyclic AMP-regulated phosphoprotein, 32 kDa (DARPP-32) mRNA and protein, and mRNA levels of other markers of medium spiny neuron maturation. We were, however, unable to prove that HDAC inhibitors directly lead to remodeling of Ppp1r1b chromatin. In addition, induction of DARPP-32 by brain-derived neurotrophic factor was inhibited by histone deacetylase inhibitors. Although BDNF-induced increases in pTrkB, pAkt, pERK and Egr-1 were unchanged by combined application with VPA, the increase in DARPP-32 was relatively diminished. Strikingly, the NGF1A-binding protein, Nab2, was induced by BDNF, but not in the presence of VPA or TSA. Gel shift analysis showed that ?-Nab2 super-shifted a band that is more prominent with extract derived from BDNF-treated neurons than with extracts from cultures treated with VPA alone or VPA plus BDNF. In addition, overexpression of Nab2 induced DARPP-32. We conclude that histone deacetylase inhibitors inhibit the induction of Nab2 by BDNF, and thereby the relative induction of DARPP-32. PMID:24204683

Morant, Andrika; Bezdecny, Steve; Ehrlich, Michelle E.

2013-01-01

241

The deacetylase HDAC6 is a novel critical component of stress granules involved in the stress response  

PubMed Central

An essential part of the cellular response to environmental stress is a reversible translational suppression, taking place in dynamic cytoplasmic structures called stress granules (SGs). We discovered that HDAC6, a cytoplasmic deacetylase that acts on tubulin and HSP90 and also binds ubiquitinated proteins with high affinity, is a novel critical SG component. We found that HDAC6 interacts with another SG protein, G3BP (Ras-GTPase-activating protein SH3 domain-binding protein 1), and localizes to SGs under all stress conditions tested. We show that pharmacological inhibition or genetic ablation of HDAC6 abolishes SG formation. Intriguingly, we found that the ubiquitin-binding domain of HDAC6 is essential and that SGs are strongly positive for ubiquitin. Moreover, disruption of microtubule arrays or impairment of motor proteins also prevents formation of SGs. These findings identify HDAC6 as a central component of the stress response, and suggest that it coordinates the formation of SGs by mediating the motor-protein-driven movement of individual SG components along microtubules. PMID:18079183

Kwon, SoHee; Zhang, Yu; Matthias, Patrick

2007-01-01

242

HDAC6 and Ovarian Cancer  

PubMed Central

The special class IIb histone deacetylase, HDAC6, plays a prominent role in many cellular processes related to cancer, including oncogenesis, the cell stress response, motility, and myriad signaling pathways. Many of the lessons learned from other cancers can be applied to ovarian cancer as well. HDAC6 interacts with diverse proteins such as HSP90, cortactin, tubulin, dynein, p300, Bax, and GRK2 in both the nucleus and cytoplasm to carry out these cancerous functions. Not all pro-cancer interactions of HDAC6 involve deacetylation. The idea of using HDAC6 as a target for cancer treatment continues to expand in recent years, and more potent and specific HDAC6 inhibitors are required to effectively down-regulate the tumor-prone cell signaling pathways responsible for ovarian cancer. PMID:23644884

Haakenson, Joshua; Zhang, Xiaohong

2013-01-01

243

Vorinostat, a histone deacetylase inhibitor, facilitates fear extinction and enhances expression of the hippocampal NR2B-containing NMDA receptor gene.  

PubMed

Histone acetylation, which alters the compact chromatin structure and changes the accessibility of DNA to regulatory proteins, is emerging as a fundamental mechanism for regulating gene expression. Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance fear extinction. In this study, we examined whether vorinostat, an HDAC inhibitor, facilitates fear extinction, using a contextual fear conditioning (FC) paradigm, in Sprague-Dawley rats. We found that vorinostat facilitated fear extinction. Next, the levels of global acetylated histone H3 and H4 were measured by Western blotting. We also assessed the effect of vorinostat on the hippocampal levels of NMDA receptor mRNA by real-time quantitative PCR (RT-PCR) and protein by Western blotting. 2 h after vorinostat administration, the levels acetylated histones and NR2B mRNA, but not NR1 or NR2A mRNA, were elevated in the hippocampus. The NR2B protein level was elevated 4 h after vorinostat administration. Last, we investigated the levels of acetylated histones and phospho-CREB (p-CREB) binding at the promoter of the NR2B gene using the chromatin immunoprecipitation (ChIP) assay followed by RT-PCR. The ChIP assay revealed increases in the levels of acetylated histones and they were accompanied by enhanced binding of p-CREB to its binding site at the promoter of the NR2B gene 2 h after vorinostat administration. These findings suggest that vorinostat increases the expression of NR2B in the hippocampus by enhancing histone acetylation, and this process may be implicated in fear extinction. PMID:22364833

Fujita, Yosuke; Morinobu, Shigeru; Takei, Shiro; Fuchikami, Manabu; Matsumoto, Tomoya; Yamamoto, Shigeto; Yamawaki, Shigeto

2012-05-01

244

Role of histone deacetylase activity in the developing lateral line neuromast of zebrafish larvae  

PubMed Central

Histone deacetylases are involved in many biological processes and have roles in regulating cell behaviors such as cell cycle entry, cell proliferation and apoptosis. However, the effect of histone deacetylases on the development of hair cells (HCs) has not been fully elucidated. In this study, we examined the influence of histone deacetylases on the early development of neuromasts in the lateral line of zebrafish. Hair cell development was evaluated by fluorescent immunostaining in the absence or presence of histone deacetylase inhibitors. Our results suggested that pharmacological inhibition of histone deacetylases with inhibitors, including trichostatin A, valproic acid and MS-275, reduced the numbers of both HCs and supporting cells in neuromasts. We also found that the treatment of zebrafish larvae with inhibitors caused accumulation of histone acetylation and suppressed proliferation of neuromast cells. Real-time PCR results showed that the expression of both p21 and p27 mRNA was increased following trichostatin A treatment and the increase in p53 mRNA was modest under the same conditions. However, the expression of p53 mRNA was significantly increased by treatment with a high concentration of trichostatin A. A high concentration of trichostatin A also led to increased cell death in neuromasts as detected in a TUNEL assay. Moreover, the nuclei of most of these pyknotic cells were immunohistochemically positive for cleaved caspase-3. These results suggest that histone deacetylase activity is involved in lateral line development in the zebrafish and might have a role in neuromast formation by altering cell proliferation through the expression of cell cycle regulatory proteins. PMID:24810423

He, Yingzi; Mei, Honglin; Yu, Huiqian; Sun, Shan; Ni, Wenli; Li, Huawei

2014-01-01

245

Role of histone deacetylase activity in the developing lateral line neuromast of zebrafish larvae.  

PubMed

Histone deacetylases are involved in many biological processes and have roles in regulating cell behaviors such as cell cycle entry, cell proliferation and apoptosis. However, the effect of histone deacetylases on the development of hair cells (HCs) has not been fully elucidated. In this study, we examined the influence of histone deacetylases on the early development of neuromasts in the lateral line of zebrafish. Hair cell development was evaluated by fluorescent immunostaining in the absence or presence of histone deacetylase inhibitors. Our results suggested that pharmacological inhibition of histone deacetylases with inhibitors, including trichostatin A, valproic acid and MS-275, reduced the numbers of both HCs and supporting cells in neuromasts. We also found that the treatment of zebrafish larvae with inhibitors caused accumulation of histone acetylation and suppressed proliferation of neuromast cells. Real-time PCR results showed that the expression of both p21 and p27 mRNA was increased following trichostatin A treatment and the increase in p53 mRNA was modest under the same conditions. However, the expression of p53 mRNA was significantly increased by treatment with a high concentration of trichostatin A. A high concentration of trichostatin A also led to increased cell death in neuromasts as detected in a TUNEL assay. Moreover, the nuclei of most of these pyknotic cells were immunohistochemically positive for cleaved caspase-3. These results suggest that histone deacetylase activity is involved in lateral line development in the zebrafish and might have a role in neuromast formation by altering cell proliferation through the expression of cell cycle regulatory proteins. PMID:24810423

He, Yingzi; Mei, Honglin; Yu, Huiqian; Sun, Shan; Ni, Wenli; Li, Huawei

2014-01-01

246

Targeting prostate cancer cell lines with polo-like kinase 1 inhibitors as a single agent and in combination with histone deacetylase inhibitors  

PubMed Central

Combinations of anticancer therapies with high efficacy and low toxicities are highly sought after. Therefore, we studied the effect of polo-like kinase 1 (Plk1) inhibitors on prostate cancer cells as a single agent and in combination with histone deacetylase (HDAC) inhibitors valproic acid and vorinostat. IC50s of Plk1 inhibitors BI 2536 and BI 6727 were determined in prostate cancer cells by MTS assays. Morphological and molecular changes were assessed by immunoblotting, immunofluorescence, flow cytometry, real-time RT-PCR, and pulldown assays. Efficacy of combination therapy was assessed by MTS and clonogenic assays. IC50 values in DU145, LNCaP, and PC3 cells were 50, 75, and 175 nM, respectively, for BI 2536 and 2.5, 5, and 600 nM, respectively, for BI 6727. Human prostate fibroblasts and normal prostate epithelial cells were unaffected at these concentrations. While DU145 and LNCaP cells were solely arrested in mitosis on treatment, PC3 cells accumulated in G2 phase and mitosis, suggesting a weak spindle assembly checkpoint. Combining Plk1 inhibitors with HDAC inhibitors had synergistic antitumor effects in vitro. DMSO-treated prostate cancer cells were used as controls to study the effect of Plk1 and HDAC inhibition. Plk1 inhibitors decreased proliferation and clonogenic potential of prostate cancer cells. Hence, Plk1 may serve as an important molecular target for inhibiting prostate cancer. Combining HDAC inhibitors with BI 2536 or BI 6727 may be an effective treatment strategy against prostate cancer.—Wissing, M. D., Mendonca, J., Kortenhorst, M. S. Q., Kaelber, N. S., Gonzalez, M., Kim E., Hammers, H., van Diest, P. J., Carducci, M. A., Kachhap, S. K. Targeting prostate cancer cell lines with polo-like kinase 1 inhibitors as a single agent and in combination with histone deacetylase inhibitors. PMID:23884428

Wissing, Michel D.; Mendonca, Janet; Kortenhorst, Madeleine S. Q.; Kaelber, Nadine S.; Gonzalez, Matthew; Kim, Eunice; Hammers, Hans; van Diest, Paul J.; Carducci, Michael A.; Kachhap, Sushant K.

2013-01-01

247

Differentiation therapy for the treatment of t(8;21) acute myeloid leukemia using histone deacetylase inhibitors.  

PubMed

Epigenetic modifying enzymes such as histone deacetylases (HDACs), p300, and PRMT1 are recruited by AML1/ETO, the pathogenic protein for t(8;21) acute myeloid leukemia (AML), providing a strong molecular rationale for targeting these enzymes to treat this disease. Although early phase clinical assessment indicated that treatment with HDAC inhibitors (HDACis) may be effective in t(8;21) AML patients, rigorous preclinical studies to identify the molecular and biological events that may determine therapeutic responses have not been performed. Using an AML mouse model driven by expression of AML1/ETO9a (A/E9a), we demonstrated that treatment of mice bearing t(8;21) AML with the HDACi panobinostat caused a robust antileukemic response that did not require functional p53 nor activation of conventional apoptotic pathways. Panobinostat triggered terminal myeloid differentiation via proteasomal degradation of A/E9a. Importantly, conditional A/E9a deletion phenocopied the effects of panobinostat and other HDACis, indicating that destabilization of A/E9a is critical for the antileukemic activity of these agents. PMID:24415537

Bots, Michael; Verbrugge, Inge; Martin, Benjamin P; Salmon, Jessica M; Ghisi, Margherita; Baker, Adele; Stanley, Kym; Shortt, Jake; Ossenkoppele, Gert J; Zuber, Johannes; Rappaport, Amy R; Atadja, Peter; Lowe, Scott W; Johnstone, Ricky W

2014-02-27

248

Arsenic toxicity induced endothelial dysfunction and dementia: pharmacological interdiction by histone deacetylase and inducible nitric oxide synthase inhibitors.  

PubMed

Arsenic toxicity has been reported to damage all the major organs including the brain and vasculature. Dementia including Alzheimer's disease (AD) and vascular dementia (VaD) are posing greater risk to the world population as it is now increasing at a faster rate. We have investigated the role of sodium butyrate, a selective histone deacetylase (HDAC) inhibitor and aminoguanidine, a selective inducible nitric oxide synthase (iNOS) inhibitor in pharmacological interdiction of arsenic toxicity induced vascular endothelial dysfunction and dementia in rats. Arsenic toxicity was done by administering arsenic drinking water to rats. Morris water-maze (MWM) test was used for assessment of learning and memory. Endothelial function was assessed using student physiograph. Oxidative stress (aortic superoxide anion, serum and brain thiobarbituric acid reactive species, brain glutathione) and nitric oxide levels (serum nitrite/nitrate) were also measured. Arsenic treated rats have shown impairment of endothelial function, learning and memory, reduction in serum nitrite/nitrate & brain GSH levels along with increase in serum & brain TBARS. Sodium butyrate as well as aminoguanidine significantly convalesce arsenic induced impairment of learning, memory, endothelial function, and alterations in various biochemical parameters. It may be concluded that arsenic induces endothelial dysfunction and dementia, whereas, sodium butyrate, a HDAC inhibitor as well as aminoguanidine, a selective iNOS inhibitor may be considered as potential agents for the management of arsenic induced endothelial dysfunction and dementia. PMID:23921152

Sharma, Bhupesh; Sharma, P M

2013-11-15

249

Differentiation therapy for the treatment of t(8;21) acute myeloid leukemia using histone deacetylase inhibitors  

PubMed Central

Epigenetic modifying enzymes such as histone deacetylases (HDACs), p300, and PRMT1 are recruited by AML1/ETO, the pathogenic protein for t(8;21) acute myeloid leukemia (AML), providing a strong molecular rationale for targeting these enzymes to treat this disease. Although early phase clinical assessment indicated that treatment with HDAC inhibitors (HDACis) may be effective in t(8;21) AML patients, rigorous preclinical studies to identify the molecular and biological events that may determine therapeutic responses have not been performed. Using an AML mouse model driven by expression of AML1/ETO9a (A/E9a), we demonstrated that treatment of mice bearing t(8;21) AML with the HDACi panobinostat caused a robust antileukemic response that did not require functional p53 nor activation of conventional apoptotic pathways. Panobinostat triggered terminal myeloid differentiation via proteasomal degradation of A/E9a. Importantly, conditional A/E9a deletion phenocopied the effects of panobinostat and other HDACis, indicating that destabilization of A/E9a is critical for the antileukemic activity of these agents. PMID:24415537

Bots, Michael; Verbrugge, Inge; Martin, Benjamin P.; Salmon, Jessica M.; Ghisi, Margherita; Baker, Adele; Stanley, Kym; Shortt, Jake; Ossenkoppele, Gert J.; Zuber, Johannes; Rappaport, Amy R.; Atadja, Peter; Lowe, Scott W.

2014-01-01

250

The histone deacetylase inhibitor, LBH589, promotes the systemic cytokine and effector responses of adoptively transferred CD8+ T cells  

PubMed Central

Background Histone deacetylase (HDAC) inhibitors are a class of agents that have potent antitumor activity with a reported ability to upregulate MHC and costimulatory molecule expression. We hypothesized that epigenetic pharmacological immunomodulation could sensitize tumors to immune mediated cell death with an adoptive T cell therapy. Methods The pan-HDAC inhibitor, LBH589, was combined with gp100 specific T cell immunotherapy in an in vivo B16 melanoma model and in an in vivo non-tumor bearing model. Tumor regression, tumor specific T cell function and phenotype, and serum cytokine levels were evaluated. Results Addition of LBH589 to an adoptive cell transfer therapy significantly decreased tumor burden while sustaining systemic pro-inflammatory levels. Furthermore, LBH589 was able to enhance gp100 specific T cell survival and significantly decrease T regulatory cell populations systemically and intratumorally. Even in the absence of tumor, LBH589 was able to enhance the proliferation, retention, and polyfunctional status of tumor specific T cells, suggesting its effects were T cell specific. In addition, LBH589 induced significantly higher levels of the IL-2 receptor (CD25) and the co-stimulatory molecule OX-40 in T cells. Conclusion These results demonstrate that immunomodulation of adoptively transferred T cells by LBH589 provides a novel mechanism to increase in vivo antitumor efficacy of effector CD8 T cells. PMID:25054063

2014-01-01

251

Compound K, a metabolite of ginseng saponin, inhibits colorectal cancer cell growth and induces apoptosis through inhibition of histone deacetylase activity.  

PubMed

In this study, we investigated the molecular mechanisms underlying the anti-proliferative effects of Compound K, with specific reference to histone modification. Exposure of HT-29 human colon cancer cells to Compound K resulted in time-dependent inhibition of histone deacetylase (HDAC) activity, mRNA and protein expression. Compound K treatment induced unmethylation of the RUNX3 promoter region such as TSA treatment and an accumulation of acetylated histones H3 and H4 within the total cellular chromatin, resulting in an enhanced ability of these histones to bind to the promoter sequences of the tumor suppressor gene Runt-related transcription factor 3 (RUNX3). Treatment of cells with Compound K increased the mRNA and protein expression of RUNX3, as well as p21, a downstream target of RUNX3. These alterations were consistent with cell cycle arrest at the G0/G1 phases and induction of apoptosis. Our results provide new insights into the mechanisms of Compound K action in human colorectal cancer cells and suggest that HDAC inhibition presents a novel approach to prevent or treat colorectal cancer. PMID:24100442

Kang, Kyoung Ah; Piao, Mei Jing; Kim, Ki Cheon; Zheng, Jian; Yao, Cheng Wen; Cha, Ji Won; Kim, Hye Sun; Kim, Dong Hyun; Bae, Suk Chul; Hyun, Jin Won

2013-12-01

252

Histone deacetylase inhibitors repress macrophage migration inhibitory factor (MIF) expression by targeting MIF gene transcription through a local chromatin deacetylation  

Microsoft Academic Search

The cytokine macrophage migration inhibitory factor plays a central role in inflammation, cell proliferation and tumorigenesis. Moreover, macrophage migration inhibitory factor levels correlate with tumor aggressiveness and metastatic potential. Histone deacetylase inhibitors are potent antitumor agents recently introduced in the clinic. Therefore, we hypothesized that macrophage migration inhibitory factor would represent a target of histone deacetylase inhibitors. Confirming our hypothesis,

Jérôme Lugrin; Xavier C. Ding; Didier Le Roy; Anne-Laure Chanson; Fred C. G. J. Sweep; Thierry Calandra; Thierry Roger

2009-01-01

253

The acetylome regulators Hdac1 and Hdac2 differently modulate intestinal epithelial cell dependent homeostatic responses in experimental colitis.  

PubMed

Histone deacetylases (Hdac) remove acetyl groups from proteins, influencing global and specific gene expression. Hdacs control inflammation, as shown by Hdac inhibitor-dependent protection from dextran sulfate sodium (DSS)-induced murine colitis. Although tissue-specific Hdac knockouts show redundant and specific functions, little is known of their intestinal epithelial cell (IEC) role. We have shown previously that dual Hdac1/Hdac2 IEC-specific loss disrupts cell proliferation and determination, with decreased secretory cell numbers and altered barrier function. We thus investigated how compound Hdac1/Hdac2 or Hdac2 IEC-specific deficiency alters the inflammatory response. Floxed Hdac1 and Hdac2 and villin-Cre mice were interbred. Compound Hdac1/Hdac2 IEC-deficient mice showed chronic basal inflammation, with increased basal disease activity index (DAI) and deregulated Reg gene colonic expression. DSS-treated dual Hdac1/Hdac2 IEC-deficient mice displayed increased DAI, histological score, intestinal permeability, and inflammatory gene expression. In contrast to double knockouts, Hdac2 IEC-specific loss did not affect IEC determination and growth, nor result in chronic inflammation. However, Hdac2 disruption protected against DSS colitis, as shown by decreased DAI, intestinal permeability and caspase-3 cleavage. Hdac2 IEC-specific deficient mice displayed increased expression of IEC gene subsets, such as colonic antimicrobial Reg3b and Reg3g mRNAs, and decreased expression of immune cell function-related genes. Our data show that Hdac1 and Hdac2 are essential IEC homeostasis regulators. IEC-specific Hdac1 and Hdac2 may act as epigenetic sensors and transmitters of environmental cues and regulate IEC-mediated mucosal homeostatic and inflammatory responses. Different levels of IEC Hdac activity may lead to positive or negative outcomes on intestinal homeostasis during inflammation. PMID:24525021

Turgeon, Naomie; Gagné, Julie Moore; Blais, Mylène; Gendron, Fernand-Pierre; Boudreau, François; Asselin, Claude

2014-04-01

254

Histone deacetylase inhibitors prevent the degradation and restore the activity of glucocerebrosidase in Gaucher disease  

PubMed Central

Gaucher disease (GD) is caused by a spectrum of genetic mutations within the gene encoding the lysosomal enzyme glucocerebrosidase (GCase). These mutations often lead to misfolded proteins that are recognized by the unfolded protein response system and are degraded through the ubiquitin–proteasome pathway. Modulating this pathway with histone deacetylase inhibitors (HDACis) has been shown to improve protein stability in other disease settings. To identify the mechanisms involved in the regulation of GCase and determine the effects of HDACis on protein stability, we investigated the most prevalent mutations for nonneuronopathic (N370S) and neuronopathic (L444P) GD in cultured fibroblasts derived from GD patients and HeLa cells transfected with these mutations. The half-lives of mutant GCase proteins correspond to decreases in protein levels and enzymatic activity. GCase was found to bind to Hsp70, which directed the protein to TCP1 for proper folding, and to Hsp90, which directed the protein to the ubiquitin–proteasome pathway. Using a known HDACi (SAHA) and a unique small-molecule HDACi (LB-205), GCase levels increased rescuing enzymatic activity in mutant cells. The increase in the quantity of protein can be attributed to increases in protein half-life that correspond primarily with a decrease in degradation rather than an increase in chaperoned folding. HDACis reduce binding to Hsp90 and prevent subsequent ubiquitination and proteasomal degradation without affecting binding to Hsp70 or TCP1. These findings provide insight into the pathogenesis of GD and indicate a potent therapeutic potential of HDAC inhibitors for the treatment of GD and other human protein misfolding disorders. PMID:22160715

Lu, Jie; Yang, Chunzhang; Chen, Masako; Ye, Donald Y.; Lonser, Russell R.; Brady, Roscoe O.; Zhuang, Zhengping

2011-01-01

255

Histone deacetylase inhibition reduces cardiac connexin43 expression and gap junction communication  

PubMed Central

Histone deacetylase inhibitors (HDACIs) are being investigated as novel therapies for cancer, inflammation, neurodegeneration, and heart failure. The effects of HDACIs on the functional expression of cardiac gap junctions (GJs) are essentially unknown. The purpose of this study was to determine the effects of trichostatin A (TSA) and vorinostat (VOR) on functional GJ expression in ventricular cardiomyocytes. The effects of HDAC inhibition on connexin43 (Cx43) expression and functional GJ assembly were examined in primary cultured neonatal mouse ventricular myocytes. TSA and VOR reduced Cx43 mRNA, protein expression, and immunolocalized Cx43 GJ plaque area within ventricular myocyte monolayer cultures in a dose-dependent manner. Chromatin immunoprecipitation experiments revealed altered protein interactions with the Cx43 promoter. VOR also altered the phosphorylation state of several key regulatory Cx43 phospho-serine sites. Patch clamp analysis revealed reduced electrical coupling between isolated ventricular myocyte pairs, altered transjunctional voltage-dependent inactivation kinetics, and steady state junctional conductance inactivation and recovery relationships. Single GJ channel conductance was reduced to 54 pS only by maximum inhibitory doses of TSA (? 100 nM). These two hydroxamate pan-HDACIs exert multiple levels of regulation on ventricular GJ communication by altering Cx43 expression, GJ area, post-translational modifications (e.g., phosphorylation, acetylation), gating, and channel conductance. Although a 50% downregulation of Cx43 GJ communication alone may not be sufficient to slow ventricular conduction or induce arrhythmias, the development of class-selective HDACIs may help avoid the potential negative cardiovascular effects of pan-HDACI. PMID:23596417

Xu, Qin; Lin, Xianming; Andrews, Laura; Patel, Dakshesh; Lampe, Paul D.; Veenstra, Richard D.

2013-01-01

256

Two Histone Deacetylases, FfHda1 and FfHda2, Are Important for Fusarium fujikuroi Secondary Metabolism and Virulence  

PubMed Central

Histone modifications are crucial for the regulation of secondary metabolism in various filamentous fungi. Here we studied the involvement of histone deacetylases (HDACs) in secondary metabolism in the phytopathogenic fungus Fusarium fujikuroi, a known producer of several secondary metabolites, including phytohormones, pigments, and mycotoxins. Deletion of three Zn2+-dependent HDAC-encoding genes, ffhda1, ffhda2, and ffhda4, indicated that FfHda1 and FfHda2 regulate secondary metabolism, whereas FfHda4 is involved in developmental processes but is dispensable for secondary-metabolite production in F. fujikuroi. Single deletions of ffhda1 and ffhda2 resulted not only in an increase or decrease but also in derepression of metabolite biosynthesis under normally repressing conditions. Moreover, double deletion of both the ffhda1 and ffhda2 genes showed additive but also distinct phenotypes with regard to secondary-metabolite biosynthesis, and both genes are required for gibberellic acid (GA)-induced bakanae disease on the preferred host plant rice, as ?ffhda1 ?ffhda2 mutants resemble the uninfected control plant. Microarray analysis with a ?ffhda1 mutant that has lost the major HDAC revealed differential expression of secondary-metabolite gene clusters, which was subsequently verified by a combination of chemical and biological approaches. These results indicate that HDACs are involved not only in gene silencing but also in the activation of some genes. Chromatin immunoprecipitation with the ?ffhda1 mutant revealed significant alterations in the acetylation state of secondary-metabolite gene clusters compared to the wild type, thereby providing insights into the regulatory mechanism at the chromatin level. Altogether, manipulation of HDAC-encoding genes constitutes a powerful tool to control secondary metabolism in filamentous fungi. PMID:24096420

Studt, L.; Schmidt, F. J.; Jahn, L.; Sieber, C. M. K.; Connolly, L. R.; Niehaus, E.-M.; Freitag, M.

2013-01-01

257

Deep brain stimulation, histone deacetylase inhibitors and glutamatergic drugs rescue resistance to fear extinction in a genetic mouse model.  

PubMed

Anxiety disorders are characterized by persistent, excessive fear. Therapeutic interventions that reverse deficits in fear extinction represent a tractable approach to treating these disorders. We previously reported that 129S1/SvImJ (S1) mice show no extinction learning following normal fear conditioning. We now demonstrate that weak fear conditioning does permit fear reduction during massed extinction training in S1 mice, but reveals specific deficiency in extinction memory consolidation/retrieval. Rescue of this impaired extinction consolidation/retrieval was achieved with d-cycloserine (N-methly-d-aspartate partial agonist) or MS-275 (histone deacetylase (HDAC) inhibitor), applied after extinction training. We next examined the ability of different drugs and non-pharmacological manipulations to rescue the extreme fear extinction deficit in S1 following normal fear conditioning with the ultimate aim to produce low fear levels in extinction retrieval tests. Results showed that deep brain stimulation (DBS) by applying high frequency stimulation to the nucleus accumbens (ventral striatum) during extinction training, indeed significantly reduced fear during extinction retrieval compared to sham stimulation controls. Rescue of both impaired extinction acquisition and deficient extinction consolidation/retrieval was achieved with prior extinction training administration of valproic acid (a GABAergic enhancer and HDAC inhibitor) or AMN082 [metabotropic glutamate receptor 7 (mGlu7) agonist], while MS-275 or PEPA (AMPA receptor potentiator) failed to affect extinction acquisition in S1 mice. Collectively, these data identify potential beneficial effects of DBS and various drug treatments, including those with HDAC inhibiting or mGlu7 agonism properties, as adjuncts to overcome treatment resistance in exposure-based therapies. This article is part of a Special Issue entitled 'Cognitive Enhancers'. PMID:22722028

Whittle, Nigel; Schmuckermair, Claudia; Gunduz Cinar, Ozge; Hauschild, Markus; Ferraguti, Francesco; Holmes, Andrew; Singewald, Nicolas

2013-01-01

258

Ab initio study of the binding of Trichostatin A (TSA) in the active site of histone deacetylase like protein (HDLP).  

PubMed

Histone deacetylase (HDAC) inhibitors have recently attracted considerable interest because of their therapeutic potential for the treatment of cell proliferative diseases. An X-ray structure of a very potent inhibitor, Trichostatin A (TSA), bound to HDLP (an HDAC analogue isolated from Aquifex aeolicus), is available. From this structure, an active site model (322 atoms), relevant for the binding of TSA and structural analogues, has been derived, and TSA has been minimized in this active site at HF 3-21G* level. The resulting conformation is in excellent accordance with the X-ray structure, and indicates a deprotonation of the hydroxamic acid in TSA by His 131. Also, a water molecule was minimized in the active site. In addition to a similar deprotonation, in accordance with a possible catalytic mechanism of HDAC as proposed by Finnin et al. (M. S. Finnin, J. R. Donigian, A. Cohen, V. M. Richon, R. A. Rifkind and P. A. Marks, Nature, 1999, 401, 188-193), a displacement of the resulting OH- ion in the active site was observed. Based on these results, the difference in energy of binding between TSA and water was calculated. The resulting value is realistic in respect to experimental binding affinities. Furthermore, the mechanism of action of the His 131-Asp 166 charge relay system was investigated. Although the Asp residue in this motif is known to substantially increase the basicity of the His residue, no proton transfer from His 131 to Asp 166 was observed on binding of TSA or water. However, in the empty protonated active site, this proton transfer does occur. PMID:12968347

Vanommeslaeghe, Kenno; Van Alsenoy, Christian; De Proft, Frank; Martins, José C; Tourwé, Dirk; Geerlings, Paul

2003-08-21

259

Design and Optimization of Novel Hydroxamate-Based Histone Deacetylase Inhibitors of Bis-Substituted Aromatic Amides Bearing Potent Activities against Tumor Growth and Metastasis.  

PubMed

Histone deacetylases (HDACs) are one of the most promising drug targets for cancer therapy, and since more than 90% of all cancer-related deaths are associated with tumor metastasis, developing strategies to inhibit tumor metastasis while retaining anti-tumor growth activity are of great interest. Herein we demonstrated the design and identification of a series of novel hydroxamate-based HDAC inhibitors bearing potent activities against tumor growth and metastasis. Optimization of the initial hit resulted in the discovery of new HDAC inhibitors through studying the structure-activity relationship. Among them, compound 11b, one of the most potent leads, exhibited nanomolar IC50 values toward inhibition of class I and IIb HDACs as well as sub-micromolar activity against proliferation and migration of breast cancer cells in vitro. More importantly, it also significantly suppressed tumor growth in a breast tumor xenograft mouse model and dose-dependently blocked in vivo tumor metastasis in a mouse pulmonary metastasis model. PMID:25360834

Yang, Feifei; Zhang, Tao; Wu, Haigang; Yang, Yang; Liu, Ning; Chen, Ang; Li, Qiang; Li, Jingjie; Qin, Liwen; Jiang, Beier; Wang, Xin; Pang, Xiufeng; Yi, Zhengfang; Liu, Mingyao; Chen, Yihua

2014-11-26

260

Synthesis, bioevaluation and docking study of 5-substitutedphenyl-1,3,4-thiadiazole-based hydroxamic acids as histone deacetylase inhibitors and antitumor agents.  

PubMed

Abstract Since the first histone deacetylase (HDAC) inhibitor (Zolinza®, widely known as suberoylanilide hydroxamic acid; SAHA) was approved by the Food and Drug Administration for the treatment of T-cell lymphoma in 2006, the search for newer HDAC inhibitors has attracted a great deal of interest of medicinal chemists worldwide. As a continuity of our ongoing research in this area, we designed and synthesized a series of 5-substitutedphenyl-1,3,4-thiadiazole-based hydroxamic acids as analogues of SAHA and evaluated their biological activities. A number of compounds in this series, for example, N(1)-hydroxy-N(8)-(5-(2-chlorophenyl)-1,3,4-thiadiazol-2-yl)octandiamide (5b), N(1)-hydroxy-N(8)-(5-(3-chlorophenyl-1,3,4-thiadiazol-2-yl)octandiamide (5c) and N(1)-hydroxy-N(8)-(5-(4-chlorophenyl)-1,3,4-thiadiazol-2-yl)octandiamide (5d), were found to possess potent anticancer cytotoxicity and HDAC inhibition effects. Compounds 5b-d were generally two- to five-fold more potent in terms of cytotoxicity compared to SAHA against five cancer cell lines tested. Docking studies revealed that these hydroxamic acid displayed higher affinities than SAHA toward HDAC8. PMID:24020585

Nam, Nguyen-Hai; Huong, Tran Lan; Dung, Do Thi Mai; Dung, Phan Thi Phuong; Oanh, Dao Thi Kim; Park, Sang Ho; Kim, Kyungrok; Han, Byung Woo; Yun, Jieun; Kang, Jong Soon; Kim, Youngsoo; Han, Sang-Bae

2014-10-01

261

Effect of Quanzhenyiqitang on apoptosis of alveolar macrophages and expression of histone deacetylase 2 in rats with chronic obstructive pulmonary disease  

PubMed Central

This study aimed to investigate the effect of Quanzhenyiqitang on alveolar macrophages (AMs) in a rat model of chronic obstructive pulmonary disease (COPD). In addition, the induction of apoptosis and regulation of histone deacetylase 2 (HDAC2) was studied to elucidate the underlying mechanisms of Quanzhenyiqitang treatment of COPD. Quanzhenyiqitang-treated serum was applied to AMs obtained from rats with COPD. A blank (control) group, an untreated serum group and an aminophylline group were also observed to evaluate the differences in AM apoptosis status, as well as the expression levels of caspase-9, caspase-8 and HDAC2. Compared with the control group, Quanzhenyiqitang-treated serum resulted in higher levels of caspase-9 and caspase-8 expression, increased apoptosis of AMs and increased expression of HDAC2 by AMs. In conclusion, Quanzhenyiqitang is capable of inducing apoptosis of AMs, which are the primary inflammatory cells in COPD, and modulating the expression of the important inflammatory factor HDAC2, producing an overall anti-inflammatory effect. PMID:24940433

LI, DA-ZHI; RUAN, SHI-WEI; CHEN, ZHI-BIN; WANG, CHUN-E.

2014-01-01

262

Hypoxia-inducible factor-1? mediates up-regulation of neprilysin by histone deacetylase-1 under hypoxia condition in neuroblastoma cells.  

PubMed

Hypoxia-inducible factor (HIF)-1 is the key transcriptional activator mediating both adaptive and pathological responses to hypoxia. The purpose of this study was to find the role of HIF-1 in regulating neprilysin (NEP) at the early stage of hypoxia and explore the underlying mechanism. In this study, we demonstrated that both NEP mRNA and protein levels in neuroblastoma cells were elevated in early stages of hypoxia. Over-expression of HIF-1? gene increased NEP mRNA/protein levels, as well as enzyme activity while knockdown of HIF-1? decreased them. Meanwhile, HIF-1? was shown to bind to histone deacetylase (HDAC)-1 and reduced the association of HDAC-1 with NEP promoter, thus activating NEP gene transcription in a de-repression way. In summary, our results indicated that hypoxia in the early stages would up-regulate NEP expression, in which interaction of HIF-1? and HDAC-1 may play a role. This study suggested that NEP up-regulation might be an adaptive response to hypoxia, which was mediated by HIF-1? binding to HDAC-1 at the early stage of hypoxia. PMID:24947680

Wang, Hecheng; Sun, Miao; Yang, Huan; Tian, Xiaosheng; Tong, Yawei; Zhou, Ting; Zhang, Tao; Fu, Yaoyun; Guo, Xiangyang; Fan, Dongsheng; Yu, Albert; Fan, Ming; Wu, Xuefei; Xiao, Weizhong; Chui, Dehua

2014-10-01

263

Histone deacetylase inhibitors activate CIITA and MHC class II antigen expression in diffuse large B-cell lymphoma  

PubMed Central

Diffuse large B-cell lymphoma (DLBCL), the most common form of non-Hodgkin's lymphoma (NHL) diagnosed in the USA, consists of at least two distinct subtypes: germinal centre B (GCB) and activated B-cell (ABC). Decreased MHC class II (MHCII) expression on the tumours in both DLBCL subtypes directly correlates with significant decreases in patient survival. One common mechanism accounting for MHCII down-regulation in DLBCL is reduced expression of the MHC class II transactivator (CIITA), the master regulator of MHCII transcription. Furthermore, reduced CIITA expression in ABC DLBCL correlates with the presence of the transcriptional repressor positive regulatory domain-I-binding factor-1 (PRDI-BF1). However, the mechanisms underlying down-regulation of CIITA in GCB DLBCL are currently unclear. In this study, we demonstrate that neither PRDI-BF1 nor CpG hypermethylation at the CIITA promoters are responsible for decreased CIITA in GCB DLBCL. In contrast, histone modifications associated with an open chromatin conformation and active transcription were significantly lower at the CIITA promoters in CIITA? GCB cells compared with CIITA+ B cells, which suggests that epigenetic mechanisms contribute to repression of CIITA transcription. Treatment of CIITA? or CIITAlow GCB cells with several different histone deacetylase inhibitors (HDACi) activated modest CIITA and MHCII expression. However, CIITA and MHCII levels were significantly higher in these cells after exposure to the HDAC-1-specific inhibitor MS-275. These results suggest that CIITA transcription is repressed in GCB DLBCL cells through epigenetic mechanisms involving HDACs, and that HDACi treatment can alleviate repression. These observations may have important implications for patient therapy. PMID:23789844

Cycon, Kelly A; Mulvaney, Kathleen; Rimsza, Lisa M; Persky, Daniel; Murphy, Shawn P

2013-01-01

264

Basolateral amygdala activity is required for enhancement of memory consolidation produced by histone deacetylase inhibition in the hippocampus.  

PubMed

Histone acetylation, a type of chromatin modification that allows increased gene transcription and can be pharmacologically promoted by histone deacetylase (HDAC) inhibitors (HDACis), has been consistently associated with promoting memory formation in the hippocampus. The basolateral nucleus of the amygdala (BLA) is a brain area crucially involved in enabling hormones and drugs to influence memory formation. Here, we show that BLA activity is required for memory enhancement by intrahippocampal administration of an HDACi. Two different HDACis, sodium butyrate (NaB) and trichostatin A (TSA), differentially enhanced the retention of memory for inhibitory avoidance (IA) when administered to the dorsal hippocampus after training. TSA showed a biphasic pattern of response during consolidation, in which infusions given immediately or 3h after training produced memory enhancement, whereas no effect was observed when it was infused 1.5 or 6h posttraining. Muscimol (MUS)-induced unilateral functional inactivation of the BLA prevented the enhancement of memory retention produced by posttraining infusion of TSA into the ipsilateral hippocampus. TSA did not affect IA extinction or reconsolidation. These results indicate that HDACis can increase IA memory retention when given into the hippocampus, and, most importantly, BLA activity is necessary for enabling HDACi-induced influences on memory formation. PMID:24583371

Blank, Martina; Dornelles, Arethuza S; Werenicz, Aline; Velho, Luciana A; Pinto, Diana F; Fedi, Ana Cláudia; Schröder, Nadja; Roesler, Rafael

2014-05-01

265

Oxidative Stress, Histone Deacetylase and Corticosteroid Resistance in Severe Asthma and COPD  

Microsoft Academic Search

Cigarette smoke-mediated oxidative stress enhances inflammation through the activation of stress kinases (JNK, ERK, p38) and redox-sensitive transcription factors such as NF-? B and AP-1 resulting in increased expression of distinct pro-inflammatory mediators. Cigarette smoke and oxidants alter chromatin remodelling by targeted acetylation of histones and inhibition of histone deacetylase activity and in so doing further enhances inflammatory gene expression.

David Adenuga; Irfan Rahman

2007-01-01

266

RBP1 recruits the mSIN3-histone deacetylase complex to the pocket of retinoblastoma tumor suppressor family proteins found in limited discrete regions of the nucleus at growth arrest.  

PubMed

Retinoblastoma (RB) tumor suppressor family pocket proteins induce cell cycle arrest by repressing transcription of E2F-regulated genes through both histone deacetylase (HDAC)-dependent and -independent mechanisms. In this study we have identified a stable complex that accounts for the recruitment of both repression activities to the pocket. One component of this complex is RBP1, a known pocket-binding protein that exhibits both HDAC-dependent and -independent repression functions. RB family proteins were shown to associate via the pocket with previously identified mSIN3-SAP30-HDAC complexes containing exclusively class I HDACs. Such enzymes do not interact directly with RB family proteins but rather utilize RBP1 to target the pocket. This mechanism was shown to account for the majority of RB-associated HDAC activity. We also show that in quiescent normal human cells this entire RBP1-mSIN3-SAP30-HDAC complex colocalizes with both RB family members and E2F4 in a limited number of discrete regions of the nucleus that in other studies have been shown to represent the initial origins of DNA replication following growth stimulation. These results suggest that RB family members, at least in part, drive exit from the cell cycle by recruitment of this HDAC complex via RBP1 to repress transcription from E2F-dependent promoters and possibly to alter chromatin structure at DNA origins. PMID:11283269

Lai, A; Kennedy, B K; Barbie, D A; Bertos, N R; Yang, X J; Theberge, M C; Tsai, S C; Seto, E; Zhang, Y; Kuzmichev, A; Lane, W S; Reinberg, D; Harlow, E; Branton, P E

2001-04-01

267

RBP1 Recruits the mSIN3-Histone Deacetylase Complex to the Pocket of Retinoblastoma Tumor Suppressor Family Proteins Found in Limited Discrete Regions of the Nucleus at Growth Arrest  

PubMed Central

Retinoblastoma (RB) tumor suppressor family pocket proteins induce cell cycle arrest by repressing transcription of E2F-regulated genes through both histone deacetylase (HDAC)-dependent and -independent mechanisms. In this study we have identified a stable complex that accounts for the recruitment of both repression activities to the pocket. One component of this complex is RBP1, a known pocket-binding protein that exhibits both HDAC-dependent and -independent repression functions. RB family proteins were shown to associate via the pocket with previously identified mSIN3-SAP30-HDAC complexes containing exclusively class I HDACs. Such enzymes do not interact directly with RB family proteins but rather utilize RBP1 to target the pocket. This mechanism was shown to account for the majority of RB-associated HDAC activity. We also show that in quiescent normal human cells this entire RBP1-mSIN3-SAP30-HDAC complex colocalizes with both RB family members and E2F4 in a limited number of discrete regions of the nucleus that in other studies have been shown to represent the initial origins of DNA replication following growth stimulation. These results suggest that RB family members, at least in part, drive exit from the cell cycle by recruitment of this HDAC complex via RBP1 to repress transcription from E2F-dependent promoters and possibly to alter chromatin structure at DNA origins. PMID:11283269

Lai, Albert; Kennedy, Brian K.; Barbie, David A.; Bertos, Nicholas R.; Yang, Xiang Jiao; Theberge, Marie-Christine; Tsai, Shih-Chang; Seto, Edward; Zhang, Yi; Kuzmichev, Andrei; Lane, William S.; Reinberg, Danny; Harlow, Ed; Branton, Philip E.

2001-01-01

268

HDAC inhibitors and immunotherapy; a double edged sword?  

PubMed Central

Epigenetic modifications, like histone acetylation, are essential for regulating gene expression within cells. Cancer cells acquire pathological epigenetic modifications resulting in gene expression patterns that facilitate and sustain tumorigenesis. Epigenetic manipulation therefore is emerging as a novel targeted therapy for cancer. Histone Acetylases (HATs) and Histone Deacetylases (HDACs) regulate histone acetylation and hence gene expression. Histone deacetylase (HDAC) inhibitors are well known to affect cancer cell viability and biology and are already in use for the treatment of cancer patients. Immunotherapy can lead to clinical benefit in selected cancer patients, especially in patients with limited disease after tumor debulking. HDAC inhibitors can potentially synergize with immunotherapy by elimination of tumor cells. The direct effects of HDAC inhibitors on immune cell function, however, remain largely unexplored. Initial data have suggested HDAC inhibitors to be predominantly immunosuppressive, but more recent reports have challenged this view. In this review we will discuss the effects of HDAC inhibitors on tumor cells and different immune cell subsets, synergistic interactions and possible mechanisms. Finally, we will address future challenges and potential application of HDAC inhibitors in immunocombination therapy of cancer. PMID:25115382

Kroesen, Michiel; Armandari, Inna; Hoogerbrugge, Peter M.; Adema, Gosse J.

2014-01-01

269

A phase I-II study of the histone deacetylase inhibitor vorinostat plus sequential weekly paclitaxel and doxorubicin-cyclophosphamide in locally advanced breast cancer.  

PubMed

Histone deacetylases (HDACs) are a family of enzymes that regulate chromatin remodeling and gene transcription. Vorinostat is a panHDAC inhibitor that sensitizes breast cancer cells to taxanes and trastuzumab by suppressing HDAC6 and Hsp90 client proteins. Fifty-five patients with clinical stage IIA-IIIC breast cancer received 12 weekly doses of paclitaxel (80 mg/m(2)) plus vorinostat (200-300 mg PO BID) on days 1-3 of each paclitaxel dose plus trastuzumab (for Her2/neu positive disease only), followed by doxorubicin/cyclophosphamide (60/600 mg/m(2) every 2 weeks plus pegfilgrastim). The primary study endpoint was pathologic complete response (pCR). pCR occurred in 13 of 24 evaluable patients with Her2-positive disease (54, 95 % confidence intervals [CI] 35-72 %), which met the prespecified study endpoint. pCR occurred in 4 of 15 patients with triple negative disease (27, 95 % CI 11-52 %) and none of 12 patients with ER-positive, Her2/neu negative disease (0, 95 % CI 0-24 %), which did not meet the prespecified endpoint. ER-positive tumors exhibited lower Ki67 and higher Hsp70 expression, and HDAC6, Hsp70, p21, and p27 expression were not predictive of response. Vorinostat increased acetylation of Hsp90 and alpha tubulin, and reduced expression of Hsp90 client proteins and HDAC6 in the primary tumor. Combination of vorinostat with weekly paclitaxel plus trastuzumab followed by doxorubicin-cyclophosphamide is associated with a high pCR rate in locally advanced Her2/neu positive breast cancer. Consistent with cell line and xenograft data, vorinostat increased acetylation of Hsp90 and alpha tubulin, and decreased Hsp90 client protein and HDAC6 expression in human breast cancers in vivo. PMID:24903226

Tu, Yifan; Hershman, Dawn L; Bhalla, Kapil; Fiskus, Warren; Pellegrino, Christine M; Andreopoulou, Eleni; Makower, Della; Kalinsky, Kevin; Fehn, Karen; Fineberg, Susan; Negassa, Abdissa; Montgomery, Leslie L; Wiechmann, Lisa S; Alpaugh, R Katherine; Huang, Min; Sparano, Joseph A

2014-07-01

270

Cigarette smoke impairs phagocytosis of apoptotic neutrophils by alveolar macrophages via inhibition of the histone deacetylase/Rac/CD9 pathways.  

PubMed

Efferocytosis, which is the homeostatic phagocytosis of apoptotic cells, prevents the release of toxic intracellular contents and subsequent tissue damage. Impairment of efferocytosis was reported in alveolar macrophages (AMs) of patients with chronic obstructive pulmonary disease (COPD), a common disease caused by smoking. In COPD, histone deacetylase (HDAC) activity is reduced in AMs. We investigated whether the reduction of HDAC activity is associated with the impairment of efferocytosis. Murine AMs were collected by bronchoalveolar lavage and their ability to efferocytose apoptotic human polymorphonuclear leukocytes was assessed. Pre-treatment of AMs with cigarette smoke extract (CSE) or trichostatin A (TSA), an HDAC inhibitor, suppressed efferocytosis and CSE reduced HDAC activity. TSA inhibited the activity of Rac, a key mediator of efferocytosis. These TSA-induced impairments were restored by treatment of AMs with aminophylline, a potent activator of HDAC. To further elucidate the underlying mechanism, we explored a role of CD9 in TSA-induced impairment of efferocytosis. CD9 is a transmembrane protein of the tetraspanin family that facilitates the uptake of several pathogens and other material. TSA profoundly down-regulated the expression of CD9 on AMs. The expression of CD9 was partly down-regulated by the Rac inhibitor. Pretreatment with an anti-CD9 mAb or CD9 small interfering RNA inhibited efferocytosis, which was attributable to the reduced binding of AMs to apoptotic cells. These results suggest that smoking impairs efferocytosis via inhibition of HDAC/Rac/CD9 pathways. Aminophylline/theophylline is effective in restoring the impairment of efferocytosis and might have benefit for the treatment of patients with COPD. PMID:23988617

Noda, Naotaka; Matsumoto, Koichiro; Fukuyama, Satoru; Asai, Yukari; Kitajima, Hiroko; Seki, Nanae; Matsunaga, Yuko; Kan-O, Keiko; Moriwaki, Atsushi; Morimoto, Konosuke; Inoue, Hiromasa; Nakanishi, Yoichi

2013-11-01

271

The E7 oncoprotein associates with Mi2 and histone deacetylase activity to promote cell growth.  

PubMed Central

E7 is the main transforming protein of human papilloma virus type 16 (HPV16) which is implicated in the formation of cervical cancer. The transforming activity of E7 has been attributed to its interaction with the retinoblastoma (Rb) tumour suppressor. However, Rb binding is not sufficient for transformation by E7. Mutations within a zinc finger domain, which is dispensable for Rb binding, also abolish E7 transformation functions. Here we show that HPV16 E7 associates with histone deacetylase in vitro and in vivo, via its zinc finger domain. Using a genetic screen, we identify Mi2beta, a component of the recently identified NURD histone deacetylase complex, as a protein that binds directly to the E7 zinc finger. A zinc finger point mutant which is unable to bind Mi2beta and histone deacetylase but is still able to bind Rb fails to overcome cell cycle arrest in osteosarcoma cells. Our results suggest that the binding to a histone deacetylase complex is an important parameter for the growthpromoting activity of the human papilloma virus E7 protein. This provides the first indication that viral oncoproteins control cell proliferation by targeting deacetylation pathways. PMID:10228159

Brehm, A; Nielsen, S J; Miska, E A; McCance, D J; Reid, J L; Bannister, A J; Kouzarides, T

1999-01-01

272

Phenylbutyrate, a histone deacetylase inhibitor, protects against Adriamycin-induced cardiac injury  

Microsoft Academic Search

Cardiac injury is a major complication for oxidative-stress-generating anticancer agents exemplified by Adriamycin (ADR). Recently, several histone deacetylase inhibitors (HDACIs) including phenylbutyrate (PBA) have shown promise in the treatment of cancer with little known toxicity to normal tissues. PBA has been shown to protect against oxidative stress in normal tissues. Here, we examined whether PBA might protect heart against ADR

Chotiros Daosukho; Yumin Chen; Teresa Noel; Pradoldej Sompol; Ramaneeya Nithipongvanitch; Joyce M. Velez; Terry D. Oberley; Daret K. St. Clair

2007-01-01

273

Histone Deacetylase-3 antagonizes Aspirin-stimulated Endothelial Nitric Oxide production by reversing Aspirin-induced lysine acetylation of Endothelial Nitric Oxide Synthase  

PubMed Central

Rationale Low-dose acetylsalicylic acid (aspirin) is widely used in the treatment and prevention of vascular atherothrombosis. Cardiovascular doses of aspirin also reduce systemic blood pressure and improve endothelium-dependent vasorelaxation in patients with atherosclerosis or risk factors for atherosclerosis. Aspirin can acetylate proteins, other than its pharmacological target cyclooxygenase (COX), at lysine residues. The role of lysine acetylation in mediating the effects of low-dose aspirin on the endothelium is not known. Objective To determine the role of lysine acetylation of eNOS in the regulation of endothelial NO production by low-dose aspirin, and to examine whether the lysine deacetylase Histone Deacetylase-3 (HDAC3) antagonizes the effect of low-dose aspirin on endothelial NO production by reversing acetylation of functionally critical eNOS lysine residues. Methods and results Low concentrations of aspirin induce lysine acetylation of eNOS, stimulating eNOS enzymatic activity and endothelial NO production in a cyclooxygenase-1 (COX-1)-independent fashion. Low-dose aspirin in vivo also increases bioavailable vascular NO in an eNOS-dependent and COX-1-independent manner. Low-dose aspirin promotes the binding of eNOS to calmodulin. Lysine 609 in the calmodulin autoinhibitory domain of bovine eNOS mediates aspirin-stimulated binding of eNOS to calmodulin and eNOS-derived NO production. Overexpression of HDAC3 inhibits aspirin-stimulated lysine acetylation of eNOS, increase in eNOS enzymatic activity, eNOS-derived NO, and binding of eNOS to calmodulin. Similarly, downregulation of HDAC3 promotes lysine acetylation of eNOS, and endothelial NO generation. Conclusions Lysine acetylation of eNOS is a post-translational protein modification supporting low-dose aspirin-induced vasoprotection. HDAC3, by deacetylating aspirin-acetylated eNOS, antagonizes aspirin-stimulated endothelial production of NO. PMID:20705923

Jung, Saet-Byel; Kim, Cuk-Seong; Naqvi, Asma; Yamamori, Tohru; Mattagajasingh, Ilwola; Hoffman, Timothy A; Cole, Marsha P; Kumar, Ajay; DeRicco, Jeremy S.; Jeon, Byeong Hwa; Irani, Kaikobad

2010-01-01

274

HATs and HDACs in neurodegeneration: a tale of disconcerted acetylation homeostasis  

Microsoft Academic Search

Gradual disclosure of the molecular basis of selective neuronal apoptosis during neurodegenerative diseases reveals active participation of acetylating and deacetylating agents during the process. Several studies have now successfully manipulated neuronal vulnerability by influencing the dose and enzymatic activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs), enzymes regulating acetylation homeostasis within the nucleus, thus focusing on the importance of

R N Saha; K Pahan

2006-01-01

275

HDAC1 nuclear export induced by pathological conditions is essential for the onset of axonal damage.  

PubMed

Histone deacetylase 1 (HDAC1) is a nuclear enzyme involved in transcriptional repression. We detected cytosolic HDAC1 in damaged axons in brains of humans with multiple sclerosis and of mice with cuprizone-induced demyelination, in ex vivo models of demyelination and in cultured neurons exposed to glutamate and tumor necrosis factor-alpha. Nuclear export of HDAC1 was mediated by the interaction with the nuclear receptor CRM-1 and led to impaired mitochondrial transport. The formation of complexes between exported HDAC1 and members of the kinesin family of motor proteins hindered the interaction with cargo molecules, thereby inhibiting mitochondrial movement and inducing localized beading. This effect was prevented by inhibiting HDAC1 nuclear export with leptomycin B, treating neurons with pharmacological inhibitors of HDAC activity or silencing HDAC1 but not other HDAC isoforms. Together these data identify nuclear export of HDAC1 as a critical event for impaired mitochondrial transport in damaged neurons. PMID:20037577

Kim, Jin Young; Shen, Siming; Dietz, Karen; He, Ye; Howell, Owain; Reynolds, Richard; Casaccia, Patrizia

2010-02-01

276

Histone post-translational modifications induced by histone deacetylase inhibition in transcriptional control units of NIS gene.  

PubMed

Histone post-translational modifications (HPTMs) play a major role in control of gene transcription. Among them, histone acetylation and methylation have been extensively investigated. Histone acetylation at different residues is generally associated to active gene transcription. In contrast, histone methylation can be associated either to transcriptional activation or repression, depending primarily on the histone residue that is subjected to the modification. Herein, effects of the histone deacetylase inhibitor SAHA on the sodium-iodide symporter (NIS) gene expression were investigated in breast cancer cells (MDA157 and MDA468). SAHA treatment induces high increase of NIS mRNA levels in MDA468 cells (300-fold), but moderate increase in MDA157 cells (fivefold). Histone H3 HPTMs (acetylation and methylations) on transcriptional units of NIS gene were investigated in these cell lines upon SAHA treatment. Our data indicate that HPTMs, particularly the H3 lysine 27 trimethylation, may operate in contrast to current models that relate epigenetic modifications with transcriptional activity. PMID:24844212

Baldan, Federica; Lavarone, Elisa; Di Loreto, Carla; Filetti, Sebastiano; Russo, Diego; Damante, Giuseppe; Puppin, Cinzia

2014-08-01

277

Histone Deacetylase 1/Sp1/MicroRNA-200b Signaling Accounts for Maintenance of Cancer Stem-Like Cells in Human Lung Adenocarcinoma  

PubMed Central

The presence of cancer stem-like cells (CSCs) is one of the mechanisms responsible for chemoresistance that has been a major hindrance towards lung adenocarcinoma (LAD) treatment. Recently, we have identified microRNA (miR)-200b as a key regulator of chemoresistance in human docetaxel-resistant LAD cells. However, whether miR-200b has effects on regulating CSCs remains largely unclear and needs to be further elucidated. Here, we showed that miR-200b was significantly downregulated in CD133+/CD326+ cells that exhibited properties of CSCs derived from docetaxel-resistant LAD cells. Also, restoration of miR-200b could inhibit maintenance and reverse chemoresistance of CSCs. Furthermore, suppressor of zeste-12 (Suz-12) was identified as a direct and functional target of miR-200b, and silencing of Suz-12 phenocopied the effects of miR-200b on CSCs. Additionally, overexpression of histone deacetylase (HDAC) 1 was identified as a pivotal mechanism responsible for miR-200b repression in CSCs through a specificity protein (Sp) 1-dependent mechanism, and restoration of miR-200b by HDAC1 repression significantly suppressed CSCs formation and reversed chemoresistance of CSCs by regulating Suz-12-E-cadherin signaling. Also, downregulation of HDAC1 or upregulation of miR-200b reduced the in vivo tumorigenicity of CSCs. Finally, Suz-12 was inversely correlated with miR-200b, positively correlated with HDAC1 and up-regulated in docetaxel-resistant LAD tissues compared with docetaxel-sensitive tissues. Taken together, the HDAC1/miR-200b/Suz-12-E-cadherin signaling might account for maintenance of CSCs and formation of chemoresistant phenotype in docetaxel-resistant LAD cells. PMID:25279705

Pan, Ban-Zhou; De, Wei; Wang, Rui; Chen, Long-Bang

2014-01-01

278

mSin3A/Histone Deacetylase 2- and PRMT5-Containing Brg1 Complex Is Involved in Transcriptional Repression of the Myc Target Gene cad  

PubMed Central

The role of hSWI/SNF complexes in transcriptional activation is well characterized; however, little is known about their function in transcriptional repression. We have previously shown that subunits of the mSin3A/histone deacetylase 2 (HDAC2) corepressor complex copurify with hSWI/SNF complexes. Here we show that the type II arginine-specific methyltransferase PRMT5, which is involved in cyclin E repression, can be found in association with Brg1 and hBrm-based hSWI/SNF complexes. We also show that hSWI/SNF-associated PRMT5 can methylate hypoacetylated histones H3 and H4 more efficiently than hyperacetylated histones H3 and H4. Protein-protein interaction studies indicate that PRMT5 and mSin3A interact with the same hSWI/SNF subunits as those targeted by c-Myc. These observations prompted us to examine the expression profile of the c-Myc target genes, carbamoyl-phosphate synthase-aspartate carbamoyltransferase-dihydroorotase (cad) and nucleolin (nuc). We found that cad repression is altered in cells that express inactive Brg1 and in cells treated with the HDAC inhibitor depsipeptide. Using chromatin immunoprecipitation assays, we found that Brg1, mSin3A, HDAC2, and PRMT5 are directly recruited to the cad promoter. These results suggest that hSWI/SNF complexes, through their ability to interact with activator and repressor proteins, control expression of genes involved in cell growth and proliferation. PMID:14559996

Pal, Sharmistha; Yun, Romy; Datta, Antara; Lacomis, Lynne; Erdjument-Bromage, Hediye; Kumar, Jitendra; Tempst, Paul; Sif, Said

2003-01-01

279

HDAC3 is a negative regulator of cocaine-context associated memory formation  

PubMed Central

Cocaine-induced neuroplasticity mediated by histone acetylating and deacetylating enzymes may contribute to addiction-like behaviors. For example, over expression of histone deacetylases (HDACs) 4 or 5 in the nucleus accumbens (NAc) suppresses cocaine-induced conditioned place preference (CPP) acquisition in mice. HDAC4 and HDAC5 are known to interact with HDAC3, but the role of HDAC3 in cocaine-induced behaviors has never been examined. In this study, we address the hypothesis that HDAC3 is a negative regulator of cocaine-context associated memory formation in mice. We examined the role of HDAC3 during the conditioning phase of CPP, when the mouse has the opportunity to form an associative memory between the cocaine-paired context and the subjective effects of cocaine. To address this hypothesis, Hdac3flox/flox and Hdac3+/+ mice (generated from a C57B/L6 background) were infused intra-NAc with AAV-Cre recombinase to create focal, homozygous Hdac3 deletions. Hdac3flox/flox mice exhibit significantly enhanced CPP acquisition, which correlates with increased gene expression during the consolidation phase of acquisition. Increased gene expression of c-Fos and Nr4a2 correlated with decreased HDAC3 occupancy and increased histone H4 lysine 8 (H4K8) acetylation at their promoters. Together, results from this study demonstrate that HDAC3 negatively regulates cocaine-induced CPP acquisition. PMID:23575859

Rogge, George A.; Singh, Harsimran; Dang, Richard; Wood, Marcelo A.

2013-01-01

280

Blockade of the ERK pathway enhances the therapeutic efficacy of the histone deacetylase inhibitor MS-275 in human tumor xenograft models.  

PubMed

The ERK pathway is up-regulated in various human cancers and represents a prime target for mechanism-based approaches to cancer treatment. Specific blockade of the ERK pathway alone induces mostly cytostatic rather than pro-apoptotic effects, however, resulting in a limited therapeutic efficacy of the ERK kinase (MEK) inhibitors. We previously showed that MEK inhibitors markedly enhance the ability of histone deacetylase (HDAC) inhibitors to induce apoptosis in tumor cells with constitutive ERK pathway activation in vitro. To evaluate the therapeutic efficacy of such drug combinations, we administered the MEK inhibitor PD184352 or AZD6244 together with the HDAC inhibitor MS-275 in nude mice harboring HT-29 or H1650 xenografts. Co-administration of the MEK inhibitor markedly sensitized the human xenografts to MS-275 cytotoxicity. A dose of MS-275 that alone showed only moderate cytotoxicity thus suppressed the growth of tumor xenografts almost completely as well as induced a marked reduction in tumor cellularity when administered with PD184352 or AZD6244. The combination of the two types of inhibitor also induced marked oxidative stress, which appeared to result in DNA damage and massive cell death, specifically in the tumor xenografts. The enhanced therapeutic efficacy of the drug combination was achieved by a relatively transient blockade of the ERK pathway. Administration of both MEK and HDAC inhibitors represents a promising chemotherapeutic strategy with improved safety for cancer patients. PMID:23501104

Sakamoto, Toshiaki; Ozaki, Kei-ichi; Fujio, Kohsuke; Kajikawa, Shu-hei; Uesato, Shin-ichi; Watanabe, Kazushi; Tanimura, Susumu; Koji, Takehiko; Kohno, Michiaki

2013-04-19

281

Anti-Tumor Effect in Human Lung Cancer by a Combination Treatment of Novel Histone Deacetylase Inhibitors: SL142 or SL325 and Retinoic Acids  

PubMed Central

Histone deacetylase (HDAC) inhibitors arrest cancer cell growth and cause apoptosis with low toxicity thereby constituting a promising treatment for cancer. In this study, we investigated the anti-tumor activity in lung cancer cells of the novel cyclic amide-bearing hydroxamic acid based HDAC inhibitors SL142 and SL325. In A549 and H441 lung cancer cells both SL142 and SL325 induced more cell growth inhibition and cell death than the hydroxamic acid-based HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). Moreover, the combination treatment using retinoid drugs ATRA or 9-cis RA along with SL142 or SL325 significantly induced more apoptosis and suppressed colony formation than the single use of either. The expression of the retinoic acid receptors RAR?, RAR?, RXR? and RXR? were unchanged with the treatment. However a luciferase reporter construct (pGL4. RARE 7x) containing seven tandem repeats of the retinoic acid responsible element (RARE) generated significant transcriptional activity after the combination treatment of retinoic acids and SL142 or SL325 in H441 lung cancer cells. Moreover, apoptosis-promoting Bax expression and caspase-3 activity was increased after the combination treatment. These results suggest that the combination treatment of SL142 or SL325 with retinoic acids exerts significant anti-tumor activity and is a promising therapeutic candidate to treat human lung cancer. PMID:21079797

Han, Shaoteng; Fukazawa, Takuya; Yamatsuji, Tomoki; Matsuoka, Junji; Miyachi, Hiroyuki; Maeda, Yutaka; Durbin, Mary; Naomoto, Yoshio

2010-01-01

282

Inhibition of cell survival, invasion, tumor growth and histone deacetylase activity by the dietary flavonoid luteolin in human epithelioid cancer cells.  

PubMed

Phytochemical compounds and histone deacetylase (HDAC) inhibitors are emerging as a new generation of anticancer agents with limited toxicity in cancer patients. We investigated the impact of luteolin, a dietary flavonoid, on survival, migration, invasion of cancer cells in vitro, and tumor growth in vivo. Luteolin (25-200?M) decreased the viability of human cancer cell lines originating from the lung (LNM35), colon (HT29), liver (HepG2) and breast (MCF7/6 and MDA-MB231-1833). Luteolin effectively increased the sub-G1 (apoptotic) fraction of cells through caspase-3 and -7 dependent pathways. We provide evidence that luteolin at sub-lethal/non-toxic concentrations inhibited the invasive potential of LNM35, MCF-7/6 and MDA-MB231-1833 cancer cells using Matrigel as well as the chick heart and Oris invasion assays. Moreover, we demonstrate for the first time that luteolin is a potent HDAC inhibitor that potentiates the cytotoxicity of cisplatin in LNM35 cells and decreases the growth of LNM35 tumor xenografts in athymic mice after intraperitoneal injection (20mg/kg/day for 18days) Thus, luteolin, in combination with standard anticancer drugs such as cisplatin, may be a promising HDAC inhibitor for the treatment of lung cancer. PMID:21074525

Attoub, Samir; Hassan, Ahmed H; Vanhoecke, Barbara; Iratni, Rabah; Takahashi, Takashi; Gaben, Anne-Marie; Bracke, Marc; Awad, Salma; John, Anne; Kamalboor, Hamda Ahmed; Al Sultan, Mahmood Ahmed; Arafat, Kholoud; Gespach, Christian; Petroianu, Georg

2011-01-25

283

Dissecting the mechanism of histone deacetylase inhibitors to enhance the activity of zinc finger nucleases delivered by integrase-defective lentiviral vectors.  

PubMed

Integrase-defective lentiviral vectors (IDLVs) have been of limited success in the delivery of zinc finger nucleases (ZFNs) to human cells, due to low expression. A reason for reduced gene expression has been proposed to involve the epigenetic silencing of vector genomes, carried out primarily by histone deacetylases (HDACs). In this study, we tested valproic acid (VPA), a known HDAC inhibitor (HDACi), for its ability to increase transgene expression from IDLVs, especially in the context of ZFN delivery. Using ZFNs targeting the human adenosine deaminase (ADA) gene in K562 cells, we demonstrated that treatment with VPA enhanced ZFN expression by up to 3-fold, resulting in improved allelic disruption at the ADA locus. Furthermore, three other U.S. Food and Drug Administration-approved HDACis (vorinostat, givinostat, and trichostatin-A) exhibited a similar effect on the activity of ZFN-IDLVs in K562 cells. In primary human CD34(+) cells, VPA- and vorinostat-treated cells showed higher levels of expression of both green fluorescent protein (GFP) as well as ZFNs from IDLVs. A major mechanism for the effects of HDAC inhibitors on improving expression was from their modulation of the cell cycle, and the influence of heterochromatinization was determined to be a lesser contributing factor. PMID:24568341

Joglekar, Alok V; Stein, Libby; Ho, Michelle; Hoban, Megan D; Hollis, Roger P; Kohn, Donald B

2014-07-01

284

A selective histone deacetylase-6 inhibitor improves BDNF trafficking in hippocampal neurons from Mecp2 knockout mice: implications for Rett syndrome.  

PubMed

Rett syndrome (RTT) is a neurodevelopmental disorder caused by loss-of-function mutations in the transcriptional modulator methyl-CpG-binding protein 2 (MECP2). One of the most prominent gene targets of MeCP2 is brain-derived neurotrophic factor (Bdnf), a potent modulator of activity-dependent synaptic development, function and plasticity. Dysfunctional BDNF signaling has been demonstrated in several pathophysiological mechanisms of RTT disease progression. To evaluate whether the dynamics of BDNF trafficking is affected by Mecp2 deletion, we analyzed movements of BDNF tagged with yellow fluorescent protein (YFP) in cultured hippocampal neurons by time-lapse fluorescence imaging. We found that both anterograde and retrograde vesicular trafficking of BDNF-YFP are significantly impaired in Mecp2 knockout hippocampal neurons. Selective inhibitors of histone deacetylase 6 (HDAC6) show neuroprotective effects in neurodegenerative diseases and stimulate microtubule-dependent vesicular trafficking of BDNF-containing dense core vesicles. Here, we show that the selective HDAC6 inhibitor Tubastatin-A increased the velocity of BDNF-YFP vesicles in Mecp2 knockout neurons in both directions by increasing ?-tubulin acetylation. Tubastatin-A also restored activity-dependent BDNF release from Mecp2 knockout neurons to levels comparable to those shown by wildtype neurons. These findings demonstrate that a selective HDAC6 inhibitor is a potential pharmacological strategy to reverse cellular and synaptic impairments in RTT resulting from impaired BDNF signaling. PMID:24639629

Xu, Xin; Kozikowski, Alan P; Pozzo-Miller, Lucas

2014-01-01

285

Metformin synergistically enhances antitumor activity of histone deacetylase inhibitor trichostatin a against osteosarcoma cell line.  

PubMed

Oral hypoglycemic agent metformin is commonly used for treating type II diabetes; however, initial reports demonstrated that it could be used for suppressing tumor growth in vitro and in vivo. Moreover, novel potential anticancer drug histone deacetylase (HDAC) and inhibitor trichostatin A (TSA) have been extensively studied for inducing various malignancies growth inhibition, cell cycle arrest, and apoptosis. The object of the present study was to investigate the anti-proliferation and apoptosis induction effects of metformin and TSA in osteosarcoma cell line, and to explore the mechanism of metformin and TSA in combination to inhibit the proliferation of osteosarcoma cells. After treating with metformin and TSA, the viability of osteosarcoma cell lines (MG-63 and LM8) was analyzed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) at various concentrations, cell cycle analysis of MG-63 and LM8 cell was performed by flow cytometry. Real-time polymerase chain reaction and Western Blotting were performed to determine the expression of apoptosis-related genes and proteins such as Caspase-3, Bcl-2/Bax, Cyclin D1, and p21. Protein expression of the molecules involved in 5'-adenosine monophosphate-activated protein kinase (AMPK) signaling pathway after treatment with combination was determined by Western blotting. Moreover, orthotopic xenograft tumors were challenged in nude mice to establish the murine model; tumor weight and tumor volume were monitored after drug administration separately or combined via the intraperitoneal (i.p.) route. MTT assays showed that the viability of osteosarcoma cell lines in the combination group (10 mM metformin, 0.3 ?M TSA) decreased in a concentration- and time-dependent manner; moreover, the cell cycle of MG-63 and LM8 in the combination group could be arrested in G1/G2 phase higher number compared with drug use separately. Furthermore, a combination of these drugs does not act via the AMPK signaling pathway to induce MG-63 osteosarcoma cell line growth inhibition and apoptosis. As data have showed here, metformin cotreatment increased TSA antitumor effects and have a synergistic effect on osteosarcoma cell line proliferation and apoptosis. PMID:23451817

Duo, Jian; Ma, Yulin; Wang, Guowen; Han, Xiuxin; Zhang, Chao

2013-04-01

286

Human Fibroblast Commitment to a Senescence-Like State in Response to Histone Deacetylase Inhibitors Is Cell Cycle Dependent  

Microsoft Academic Search

Humandiploidfibroblasts(HDF)completealimitednumberofcelldivisionsbeforeenteringagrowtharrest state that is termed replicative senescence. Two histone deacetylase inhibitors, sodium butyrate and trichos- tatin A, dramatically reduce the HDF proliferative life span in a manner that is dependent on one or more cell doublings in the presence of these agents. Cells arrested and subsequently released from histone deacetylase inhibitors display markers of senescence and exhibit a persistent G1block

VASILY V. OGRYZKO; TAZUKO H. HIRAI; VALYA R. RUSSANOVA; DAVID A. BARBIE; ANDBRUCE H. HOWARD

1996-01-01

287

JDP2, a Repressor of AP-1, Recruits a Histone Deacetylase 3 Complex To Inhibit the Retinoic Acid-Induced Differentiation of F9 Cells  

PubMed Central

Up-regulation of the c-jun gene is a critical event in the retinoic acid (RA)-mediated differentiation of embryonal carcinoma F9 cells. Activating transcription factor 2 (ATF-2) and p300 cooperate in the activation of transcription of the c-jun gene during the differentiation of F9 cells. We show here that the overexpression of Jun dimerization protein 2 (JDP2), a repressor of AP-1, inhibits the transactivation of the c-jun gene by ATF-2 and p300 by recruitment of the histone deacetylase 3 (HDAC3) complex, thereby repressing the RA-induced transcription of the c-jun gene and inhibiting the RA-mediated differentiation of F9 cells. Moreover, chromatin immunoprecipitation assays showed that the JDP2/HDAC3 complex, which binds to the differentiation response element within the c-jun promoter in undifferentiated F9 cells, was replaced by the p300 complex in response to RA, with an accompanying change in the histone acetylation status of the chromatin, the initiation of transcription of the c-jun gene, and the subsequent differentiation of F9 cells. These results suggest that JDP2 may be a key factor that controls the commitment of F9 cells to differentiation and shed new light on the mechanism by which an AP-1 repressor functions. PMID:12052888

Jin, Chunyuan; Li, Hongjie; Murata, Takehide; Sun, Kailai; Horikoshi, Masami; Chiu, Robert; Yokoyama, Kazunari K.

2002-01-01

288

Genomic organization and localization of the NAD-dependent histone deacetylase gene sirtuin 3 (Sirt3) in the mouse.  

PubMed

Sirtuin 3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase, which belongs to the Silent information regulator 2 (Sir2) family of histone deacetylases (sirtuin HDACs). The yeast Sir2 protein and its mammalian derivatives play a central role in epigenetic gene silencing, DNA repair and recombination, cell-cycle, microtubule organization, and in the regulation of aging. We have isolated and characterized the murine Sirt3 genomic sequence, which spans a region of 18,646 bp and which has one single genomic locus. Determination of the exon-intron splice junctions identified murine SIRT3 to be encoded by 7 exons ranging in size from 101 (exon 4) to 420 bp (exon 7). Characterization of the 5' flanking genomic region, which precedes the murine Sirt3 open reading frame, revealed a number of STATx, GATA and SP1 transcription factor binding sites. A CpG island was not detected. The 1,473-bp murine Sirt3 transcript has an open reading frame of 774 bp and encodes a 257-aa protein (cytoplasmic SIRT3) with a predictive molecular weight of 28.8 kDa and an isoelectric point of 5.82. Recently, a 1,406-bp murine SIRT3 splice variant that encodes a 334-aa mitochondrial precursor protein with a molecular weight of 36.6 kDa and an isoelectric point of 7.19 has been described. Fluorescence in situ hybridization analysis identified a single genomic locus for murine Sirt3 gene on chromosome 7F4 and which is neighbored by the Ric8 and PSMD13 genes. Our study brings light and a number of corrections and additions to previous reports on the genomic organization and the genomic sequence of murine Sirt3, which may be of importance in view of studies on potential genetic polymorphisms in relation to cellular respiration, metabolism, aging-related disease and cancer. PMID:21165558

Mahlknecht, Ulrich; Voelter-Mahlknecht, Susanne

2011-03-01

289

Nanoparticles for urothelium penetration and delivery of the histone deacetylase inhibitor belinostat for treatment of bladder cancer  

PubMed Central

Nearly 40% of patients with non-invasive bladder cancer will progress to invasive disease despite locally-directed therapy. Overcoming the bladder permeability barrier (BPB) is a challenge for intravesical drug delivery. Using the fluorophore coumarin (C6), we synthesized C6-loaded poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs), which were surface modified with a novel cell penetrating polymer, poly(guanidinium oxanorbornene) (PGON). Addition of PGON to the NP surface improved tissue penetration by 10-fold in intravesically-treated mouse bladder and ex vivo human ureter. In addition, NP-C6-PGON significantly enhanced intracellular uptake of NPs compared to NPs without PGON. To examine biological activity, we synthesized NPs that were loaded with the histone deacetylase (HDAC) inhibitor belinostat (NP-Bel-PGON). NP-Bel-PGON exhibited a significantly lower IC50 in cultured bladder cancer cells, and sustained hyperacetylation, when compared to unencapsulated belinostat. Xenograft tumors treated with NP-Bel-PGON showed a 70% reduction in volume, and a 2.5-fold higher intratumoral acetyl-H4, when compared to tumors treated with unloaded NP-PGON. PMID:23764660

Martin, Darryl T.; Hoimes, Christopher J.; Kaimakliotis, Hristos Z.; Cheng, Christopher J.; Zhang, Ke; Liu, Jingchun; Wheeler, Marcia A.; Kelly, W. Kevin; Tew, Greg N.; Saltzman, W. Mark; Weiss, Robert M.

2013-01-01

290

Pretreatment with valproic acid, a histone deacetylase inhibitor, enhances the sensitivity of the peripheral blood micronucleus assay in rodents.  

PubMed

Micronucleus (MN) assay is widely used for the determination of the genotoxic potential of new chemical entities. Improvement in the sensitivity of MN assay will be advantageous for the successful detection of marginally active genotoxins. In the past, several improvements have been made in the automated scoring of micronuclei, while very few attempts have been taken to improve the sensitivity of manual micronuclei detection. The present study aims to validate the effect of valproic acid (VPA) pretreatment on the sensitivity of peripheral blood micronucleus (PBMN) assay using cyclophosphamide (CP, 50mg/kg), methotrexate (MTX, 20mg/kg) and zidovudine (AZT, 400mg/kg) in rodents. However, to find out the optimum VPA pretreatment time as well as to detect the effect of species and age difference, separate experiments were conducted on young Swiss albino mice (24-28 days) and Sprague-Dawley rats (21-24 days), in which significant increase in MN induction was observed with 3-day VPA pretreatment in both the species. Based on these results, studies on adult mice were conducted with 3-day VPA pretreatment along with CP or MTX or AZT. The results of the present study clearly demonstrate that the 3-day VPA pretreatment significantly enhances the sensitivity of PBMN assay in peripheral blood (PB) in adult mice. After validation with other standard genotoxins as well as other HDAC (histone deacetylase) inhibitors, this model may be useful for the detection of marginally active DNA damaging agents. PMID:23142536

Ahmad, T; Shekh, K; Khan, S; Vikram, A; Yadav, L; Parekh, C V; Jena, G B

2013-02-18

291

The Histone Deacetylase Inhibitor LBH589 (Panobinostat) Modulates the Crosstalk of Lymphocytes with Hodgkin Lymphoma Cell Lines  

PubMed Central

Epigenetic changes have been implicated in the malignant phenotype of Hodgkin Reed Sternberg (HRS) cells in Hodgkin lymphoma (HL), where HRS survival and proliferation depends on the microenvironment. The histone-deacetylase (HDAC) inhibitor LBH589 (panobinostat) showed clinical efficacy but its impact on the HRS microenvironment is unclear. Hence, we analysed the effects of LBH589 on lymphocytes and also potential combination therapies. In lymphocyte-target cell killing assays, LBH589-treatment triggered an enhanced lymphocyte-dependent lysis of HL cells despite of mild lymphocytopenic effects. In co-culture experiments of lymphocytes with HL cells, LBH589 suppressed the IFNgamma-release but increased the TNFalpha secretion. Recombinant TNFalpha boosted the lymphocyte-dependent lysis of HL target cells. In HL cell lines, LBH589 induced cell death, autophagy, and an increase of MICA/B that are ligands to natural killer cell receptors. The combination of LBH589 with Brentuximab Vedotin was inefficient due to down-regulation of CD30 as a target. Combination with gemcitabine revealed highly significant effects, suggesting a potential combination for future therapy. Based on these data we suggest that LBH589 favourably modulates the cytokine network and lymphocyte activity in the HL microenvironment. PMID:24278143

Klein, Jan M.; Henke, Alexander; Sauer, Maike; Bessler, Martina; Reiners, Katrin S.; Engert, Andreas; Hansen, Hinrich P.; von Strandmann, Elke Pogge

2013-01-01

292

The histone deacetylase inhibitor trichostatin A alters microRNA expression profiles in apoptosis-resistant breast cancer cells  

PubMed Central

The development of drug resistance represents a major complication in the effective treatment of breast cancer. Epigenetic therapy, through the use of histone deacetylase inhibitors (HDACi) or demethylation agents, is an emerging area of therapeutic targeting in a number of ontological entities, particularly in the setting of aggressive therapy-resistant disease. Using the well-described HDAC inhibitor trichostatin A (TSA) we demonstrate the suppression of in vitro clonogenicity in the previously described apoptosis-resistant MCF-7TN-R breast carcinoma cell line. Additionally, recent work has demonstrated that these agents can alter the expression profile of microRNA signatures in malignant cells. Using an unbiased microRNA microarray analysis, changes in miRNA expression of MCF-7TN-R cells treated with TSA for 24 h were analyzed. We observed significant up-regulation of 22 miRNAs and down-regulation of 10 miRNAs in response to TSA treatment. Our results demonstrate that the HDACi, TSA, exerts anticancer activity in the apoptosis-resistant MCF-7TN-R breast carcinoma cell line. This activity is correlated with TSA alteration of microRNA expression profiles indicative of a less aggressive phenotype. PMID:21971930

RHODES, LYNDSAY V.; NITSCHKE, ASHLEY M.; SEGAR, H. CHRIS; MARTIN, ELIZABETH C.; DRIVER, JENNIFER L.; ELLIOTT, STEVEN; NAM, SEUNG YOON; LI, MENG; NEPHEW, KENNETH P.; BUROW, MATTHEW E.; COLLINS-BUROW, BRIDGETTE M.

2012-01-01

293

Histone Deacetylases as Transcriptional Activators? Role Reversal in Inducible Gene Regulation  

NSDL National Science Digital Library

Posttranslational modifications regulate the activity, stability, and localization of proteins that can confer both positive and negative regulation to diverse biological systems. Acetylation is a protein modification that regulates eukaryotic gene expression. The addition of acetyl groups to nuclear proteins (such as histones and transcription factors) by histone acetyltransferase enzymes is frequently associated with activation of gene expression, whereas removal of acetyl groups by deacetylase enzymes is commonly associated with transcriptional repression. This article describes a number of exceptions to this general paradigm, indicating a previously unrecognized dynamic complexity in gene regulation by reversible acetylation.

Inna Nusinzon (Northwestern University and Evanston Northwestern Healthcare;Department of Medicine and Department of Biochemistry, Molecular Biology, and Cell Biology and Department of Medicine REV); Curt M. Horvath (Northwestern University and Evanston Northwestern Healthcare;Department of Medicine and Department of Biochemistry, Molecular Biology, and Cell Biology and Department of Medicine REV)

2005-08-09

294

Synthesis and Biological Evaluation of 1-Arylsulfonyl-5-(N-hydroxyacrylamide)indoles as Potent Histone Deacetylase Inhibitors with Antitumor Activity in Vivo  

PubMed Central

A series of 1-arylsulfonyl-5-(N-hydroxyacrylamide)indoles has been identified as a new class of histone deacetylase inhibitors. Compounds 8, 11, 12, 13, and 14 demonstrated stronger antiproliferative activities than 1 (SAHA) with GI50 values ranging from 0.36 to 1.21 ?M against Hep3B, MDA-MB-231, PC-3, and A549 human cancer cell lines. Lead compound 8 showed remarkable HDAC 1, 2, and 6 isoenzymes inhibitory activities with IC50 values of 12.3, 4.0, 1.0 nM, respectively, which are comparable to 1. In in vivo efficacy evaluation against lung A549 xenograft model, 8 displayed better antitumor activity than compound 1. PMID:22439863

Lai, Mei-Jung; Huang, Han-Li; Pan, Shiow-Lin; Liu, Yi-Min; Peng, Chieh-Yu; Lee, Hsueh-Yun; Yeh, Teng-Kuang; Huang, Po-Hsien; Teng, Che-Ming; Chen, Ching-Shih; Chuang, Hsun-Yueh; Liou, Jing-Ping

2014-01-01

295

Epigenetic modifications and p21-cyclin B1 nexus in anticancer effect of histone deacetylase inhibitors in combination with silibinin on non-small cell lung cancer cells.  

PubMed

There is a renewed focus on targeted therapy against epigenetic events that are altered during the pathogenesis of lung cancer. However, the use of epigenomic modifiers as monotherapy lacks efficacy; thus, there is a need to develop safe and effective drug combinatorial regimens, which reverse epigenetic modifications and exhibit profound anticancer activity. Based on these perspectives, we evaluated, for the first time, the efficacy and associated mechanisms of a novel combinatorial regimen of histone deacetylase inhibitors (HDACi)-trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA)-with silibinin (a flavonolignan with established pre-clinical anti-lung cancer efficacy) against non-small cell lung cancer (NSCLC). Silibinin inhibited HDAC activity and decreased HDAC1-3 levels in NSCLC cells, leading to an overall increase in global histone acetylation states of histones H3 and H4. Combinations of HDCAi with silibinin synergistically augmented the cytotoxic effects of these single agents, which was associated with a dramatic increase in p21 (Cdkn1a). Subsequent ChIP assay indicated increased acetylated histone H3 and H4 levels on p21 promoter region, resulting in its increased transcription. The enhanced p21 levels promoted proteasomal degradation of cyclin B1, the limited supply of which halts the progression of cells into mitosis. Indeed, the resultant biological effect was a significant G 2/M arrest by the combination treatment, followed by apoptotic cell death. Similar epigenetic modulations were observed in vivo, together with a marked reduction in xenograft growth. These findings are both novel and highly significant in establishing that HDACi with silibinin would be safe and effective to suppress NSCLC growth. PMID:22965008

Mateen, Samiha; Raina, Komal; Jain, Anil K; Agarwal, Chapla; Chan, Daniel; Agarwal, Rajesh

2012-10-01

296

Structure–activity relationships of aryloxyalkanoic acid hydroxyamides as potent inhibitors of histone deacetylase  

Microsoft Academic Search

Syntheses of aryloxyalkanoic acid hydroxyamides are described, all of which are potent inhibitors of histone deacetylase, some being more potent in vitro than trichostatin A (IC50=3nM). Variation of the substituents on the benzene ring as well as fusion of a second ring have marked effects on potency, in vitro IC50 values down to 1nM being obtained.

Charles M. Marson; Thevaki Mahadevan; Jon Dines; Stéphane Sengmany; James M. Morrell; John P. Alao; Simon P. Joel; David M. Vigushin; R. Charles Coombes

2007-01-01

297

Histone Deacetylases and Phosphorylated Polymerase II C-Terminal Domain Recruit Spt6 for Cotranscriptional Histone Reassembly.  

PubMed

Spt6 is a multifunctional histone chaperone involved in the maintenance of chromatin structure during elongation by RNA polymerase II (Pol II). Spt6 has a tandem SH2 (tSH2) domain within its C terminus that recognizes Pol II C-terminal domain (CTD) peptides phosphorylated on Ser2, Ser5, or Try1 in vitro. Deleting the tSH2 domain, however, only has a partial effect on Spt6 occupancy in vivo, suggesting that more complex mechanisms are involved in the Spt6 recruitment. Our results show that the Ser2 kinases Bur1 and Ctk1, but not the Ser5 kinase Kin28, cooperate in recruiting Spt6, genome-wide. Interestingly, the Ser2 kinases promote the association of Spt6 in early transcribed regions and not toward the 3' ends of genes, where phosphorylated Ser2 reaches its maximum level. In addition, our results uncover an unexpected role for histone deacetylases (Rpd3 and Hos2) in promoting Spt6 interaction with elongating Pol II. Finally, our data suggest that phosphorylation of the Pol II CTD on Tyr1 promotes the association of Spt6 with the 3' ends of transcribed genes, independently of Ser2 phosphorylation. Collectively, our results show that a complex network of interactions, involving the Spt6 tSH2 domain, CTD phosphorylation, and histone deacetylases, coordinate the recruitment of Spt6 to transcribed genes in vivo. PMID:25182531

Burugula, Bala Bharathi; Jeronimo, Célia; Pathak, Rakesh; Jones, Jeffery W; Robert, François; Govind, Chhabi K

2014-11-15

298

Ribosome-inactivating proteins isolated from dietary bitter melon induce apoptosis and inhibit histone deacetylase-1 selectively in premalignant and malignant prostate cancer cells  

PubMed Central

Epidemiologic evidence suggests that a diet rich in fruits and vegetables is associated with a reduced risk of prostate cancer (PCa) development. Although several dietary compounds have been tested in preclinical PCa prevention models, no agents have been identified that either prevent the progression of premalignant lesions or treat advanced disease. Momordica charantia, known as bitter melon in English, is a plant that grows in tropical areas worldwide and is both eaten as a vegetable and used for medicinal purposes. We have isolated a protein, designated as MCP30, from bitter melon seeds. The purified fraction was verified by SDS-PAGE and mass spectrometry to contain only 2 highly related single chain Type I ribosome-inactivating proteins (RIPs), ?-momorcharin and ?-momorcharin. MCP30 induces apoptosis in PIN and PCa cell lines in vitro and suppresses PC-3 growth in vivo with no effect on normal prostate cells. Mechanistically, MCP30 inhibits histone deacetylase-1 (HDAC-1) activity and promotes histone-3 and -4 protein acetylation. Treatment with MCP30 induces PTEN expression in a prostatic intraepithelial neoplasia (PIN) and PCa cell lines resulting in inhibition of Akt phosphorylation. In addition, MCP30 inhibits Wnt signaling activity through reduction of nuclear accumulation of ?-catenin and decreased levels of c-Myc and Cyclin-D1. Our data indicate that MCP30 selectively induces PIN and PCa apoptosis and inhibits HDAC-1 activity. These results suggest that Type I RIPs derived from plants are HDAC inhibitors that can be utilized in the prevention and treatment of prostate cancer. PMID:19384952

Xiong, Su Dao; Yu, Kang; Liu, Xin Hua; Yin, Li Hui; Kirschenbaum, Alexander; Yao, Shen; Narla, Goutham; DiFeo, Analisa; Wu, Jian Buo; Yuan, Yong; Ho, Shuk-Mei; Lam, Ying Wai; Levine, Alice C.

2013-01-01

299

Effects of downregulated HDAC6 expression on the proliferation of lung cancer cells  

SciTech Connect

Histone deacetylase 6 (HDAC6) is a multifunctional, cytosolic protein deacetylase that primarily acts on {alpha}-tubulin. Here we report that stable knockdown of HDAC6 expression causes a decrease in the steady-state level of receptor tyrosine kinases, such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor {alpha}, in A549 lung cancer cells. The decreased levels of in EGFR in HDAC6-knockdown cells, which correlated with increased acetylation of microtubules, were due to increased turnover of EGFR protein. Despite the decrease in EGFR levels, A549 cells lacking functional HDAC6 appeared to grow normally, probably due to increased expression of extracellular signal-regulated kinases 1 and 2. Indeed, HDAC6-knockdown cells were more sensitive than control cells to the MEK inhibitor U0126. These results suggest that HDAC6 inhibitors combined with inhibitors of growth factor signaling may be useful as cancer therapy.

Kamemura, Kazuo [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Japan Science and Technology Corporation, CREST Research Project, Kawaguchi, Saitama 332-0012 (Japan); Ito, Akihiro [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Chemical Genomics Research Group, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan)], E-mail: akihiro-i@riken.jp; Shimazu, Tadahiro [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Matsuyama, Akihisa [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Chemical Genomics Research Group, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Japan Science and Technology Corporation, CREST Research Project, Kawaguchi, Saitama 332-0012 (Japan); Maeda, Satoko [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Yao, Tso-Pang [Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710 (United States); Horinouchi, Sueharu [Department of Biotechnology, University of Tokyo, Tokyo 113-8657 (Japan); Khochbin, Saadi [INSERM U309, Institut Albert Bonniot, Faculte de Medecine, Domaine de la Merci, 38706 La Tronche Cedex (France); Yoshida, Minoru [Chemical Genetics Laboratory, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Chemical Genomics Research Group, RIKEN Advanced Science Institute, Wako, Saitama 351-0198 (Japan); Japan Science and Technology Corporation, CREST Research Project, Kawaguchi, Saitama 332-0012 (Japan); Department of Biotechnology, University of Tokyo, Tokyo 113-8657 (Japan)

2008-09-12

300

Chidamide, a histone deacetylase inhibitor, functions as a tumor inhibitor by modulating the ratio of Bax/Bcl-2 and P21 in pancreatic cancer.  

PubMed

Chidamide is a newly designed histone deacetylase (HDAC) inhibitor that has been applied in clinical trials. This study aimed to test the effect of Chidamide on proliferation and apoptosis in pancreatic cancer cell lines and in vivo tumors, as well as to determine the underlying mechanism. The PaTu8988 pancreatic tumor cell line either in culture or inoculated in nude mice were used to evaluate the antitumor characteristics of Chidamide. Proliferation and apoptosis of cultured PaTu8988 cells were examined by CCK-8 assay and Annexin V-FITC/PI double staining assay, respectively. Alterations in protein expression, including Caspase-3, Bcl-2?like protein 4 (Bax), B-cell lymphoma 2 (Bcl-2) and p21, were tested by western blot analysis. The mRNA of different HDACs was examined by quantitative polymerase chain reaction (qPCR) experiments. Chidamide suppressed cell proliferation and induced early apoptosis of pancreatic tumor cells in a dose?dependent manner after 48 h of treatment. Similarly, the in vivo study using pancreatic tumor murine model showed that Chidamide administration significantly inhibited the growth of pancreatic tumor and induced tumor cell apoptosis. The in vitro and in vivo studies found that Chidamide treatment significantly decreased the expression of type I HDACs, uncleaved Caspase-3 and p21 and increased the ratio of Bax/Bcl-2 expression. The results from the in vitro and in vivo studies suggested Chidamide might suppress the proliferation of pancreatic tumor cells by downregulating the expression of type I HDACs and p21, and promoting mitochondrial apoptosis pathway-dependent cell apoptosis in a dose-dependent manner. The study provided more evidence for clinical administration of Chidamide that targets pancreatic tumor cells and identified potential molecular targets for the development of potent anticancer drugs. PMID:25384499

Zhao, Bin; He, Tianlin

2015-01-01

301

The Role of HDAC6 in Cancer  

PubMed Central

Histone deacetylase 6 (HDAC6), a member of the HDAC family whose major substrate is ?-tubulin, has become a target for drug development to treat cancer due to its major contribution in oncogenic cell transformation. Overexpression of HDAC6 correlates with tumorigenesis and improved survival; therefore, HDAC6 may be used as a marker for prognosis. Previous work demonstrated that in multiple myeloma cells, inhibition of HDAC6 results in apoptosis. Furthermore, HDAC6 is required for the activation of heat-shock factor 1 (HSF1), an activator of heat-shock protein encoding genes (HSPs) and CYLD, a cylindromatosis tumor suppressor gene. HDAC6 contributes to cancer metastasis since its upregulation increases cell motility in breast cancer MCF-7 cells and its interaction with cortactin regulates motility. HDAC6 also affects transcription and translation by regulating the heat-shock protein 90 (Hsp90) and stress granules (SGs), respectively. This review will discuss the role of HDAC6 in the pathogenesis and treatment of cancer. PMID:21076528

Aldana-Masangkay, Grace I.; Sakamoto, Kathleen M.

2011-01-01

302

Immunomodulatory effects of deacetylase inhibitors: therapeutic targeting of FOXP3+ regulatory T cells  

PubMed Central

Classical zinc-dependent histone deacetylases (HDACs) catalyse the removal of acetyl groups from histone tails and also from many non-histone proteins, including the transcription factor FOXP3, a key regulator of the development and function of regulatory T cells. Many HDAC inhibitors are in cancer clinical trials, but a subset of HDAC inhibitors has important anti-inflammatory or immunosuppressive effects that might be of therapeutic benefit in immuno-inflammatory disorders or post-transplantation. At least some of these effects result from the ability of HDAC inhibitors to enhance the production and suppressive functions of FOXP3+ regulatory T cells. Understanding which HDACs contribute to the regulation of the functions of regulatory T cells may further stimulate the development of new class- or subclass-specific HDAC inhibitors with applications beyond oncology. PMID:19855427

Wang, Liqing; de Zoeten, Edwin F.; Greene, Mark I.; Hancock, Wayne W.

2010-01-01

303

Inhibition of Histone Deacetylases Induces Bovine Leukemia Virus Expression In Vitro and In Vivo  

PubMed Central

Packaging into nucleosomes results in a global transcriptional repression as a consequence of exclusion of sequence-specific factors. This inhibition can be relieved by using inhibitors of histone deacetylases, acetylation being a major characteristic of transcriptionally active chromatin. Paradoxically, the expression of only ?2% of the total cellular genes is modulated by histone hyperacetylation. To unravel the potential role of this transcriptional control on BLV expression, we tested the effect of two highly specific inhibitors of deacetylases, trichostatin A (TSA) and trapoxin (TPX). Our results demonstrate that treatment with TSA efficiently enhanced long terminal repeat-directed gene expression of integrated reporter constructs in heterologous D17 stable cell lines. To further examine the biological relevance of these observations made in vitro, we analyzed ex vivo-isolated peripheral blood mononuclear cells (PBMCs) from bovine leukemia virus (BLV)-infected sheep. TSA deacetylase inhibitor induced a drastic increase in viral expression at levels comparable to those induced by treatment with phorbol-12-myristate 13-acetate and ionomycin, the most efficient activators of BLV expression known to date. TSA acted directly on BLV-infected B lymphocytes to increase viral expression and does not seem to require T-cell cooperation. Inhibition of deacetylation after treatment with TSA or TPX also significantly increased viral expression in PBMCs from cattle, the natural host for BLV. Together, our results show that BLV gene expression is, like that of a very small fraction of cellular genes, also regulated by deacetylation. PMID:11967319

Merezak, C.; Reichert, M.; Van Lint, C.; Kerkhofs, P.; Portetelle, D.; Willems, L.; Kettmann, R.

2002-01-01

304

Selective HDAC1/HDAC2 Inhibitors Induce Neuroblastoma Differentiation  

PubMed Central

Summary While cytotoxic chemotherapy remains the hallmark of cancer treatment, intensive regimens fall short in many malignancies, including high-risk neuroblastoma. One alternative strategy is to therapeutically promote tumor differentiation. We created a gene expression signature to measure neuroblast maturation, adapted it to a high-throughput platform, and screened a diversity oriented synthesis-generated small-molecule library for differentiation inducers. We identified BRD8430, containing a nine-membered lactam, an ortho-amino anilide functionality, and three chiral centers, as a selective Class I histone deacetylase (HDAC) inhibitor (HDAC1>2>3). Further investigation demonstrated that selective HDAC1/HDAC2 inhibition using compounds or RNA interference induced differentiation and decreased viability in neuroblastoma cell lines. Combined treatment with 13-cis retinoic acid augmented these effects and enhanced activation of retinoic acid signaling. Therefore, by applying a chemical genomic screening approach we identified selective HDAC1/HDAC2 inhibition as a strategy to induce neuroblastoma differentiation. PMID:23706636

Frumm, Stacey M.; Fan, Zi Peng; Ross, Kenneth N.; Duvall, Jeremy R.; Gupta, Supriya; VerPlank, Lynn; Suh, Byung-Chul; Holson, Edward; Wagner, Florence F.; Smith, William B.; Paranal, Ronald M.; Bassil, Christopher F.; Qi, Jun; Roti, Giovanni; Kung, Andrew L.; Bradner, James E.; Tolliday, Nicola; Stegmaier, Kimberly

2013-01-01

305

Valproic acid defines a novel class of HDAC inhibitors inducing differentiation of transformed cells  

PubMed Central

Histone deacetylases (HDACs) play important roles in transcriptional regulation and pathogenesis of cancer. Thus, HDAC inhibitors are candidate drugs for differentiation therapy of cancer. Here, we show that the well-tolerated antiepileptic drug valproic acid is a powerful HDAC inhibitor. Valproic acid relieves HDAC-dependent transcriptional repression and causes hyperacetylation of histones in cultured cells and in vivo. Valproic acid inhibits HDAC activity in vitro, most probably by binding to the catalytic center of HDACs. Most importantly, valproic acid induces differentiation of carcinoma cells, transformed hematopoietic progenitor cells and leukemic blasts from acute myeloid leukemia patients. More over, tumor growth and metastasis formation are significantly reduced in animal experiments. Therefore, valproic acid might serve as an effective drug for cancer therapy. PMID:11742974

Gottlicher, Martin; Minucci, Saverio; Zhu, Ping; Kramer, Oliver H.; Schimpf, Annemarie; Giavara, Sabrina; Sleeman, Jonathan P.; Lo Coco, Francesco; Nervi, Clara; Pelicci, Pier Giuseppe; Heinzel, Thorsten

2001-01-01

306

Histone deacetylase 4 promotes ubiquitin-dependent proteasomal degradation of Sp3 in SH-SY5Y cells treated with di(2-ethylhexyl)phthalate (DEHP), determining neuronal death.  

PubMed

Phthalates, phthalic acid esters, are widely used as plasticizers to produce polymeric materials in industrial production of plastics and daily consumable products. Animal studies have shown that di(2-ethylhexyl)phthalate (DEHP) may cause toxic effects in the rat brain. In the present study, chronic exposure to DEHP (0.1-100?M) caused dose-dependent cell death via the activation of caspase-3 in neuroblastoma cells. Intriguingly, this harmful effect was prevented by the pan-histone deacetylase (HDAC) inhibitor trichostatin A, by the class II HDAC inhibitor MC-1568, but not by the class I HDAC inhibitor MS-275. Furthermore, DEHP reduced specificity protein 3 (Sp3) gene expression, but not Sp3 mRNA, after 24 and 48h exposures. However, Sp3 protein reduction was prevented by pre-treatment with MC-1568, suggesting the involvement of class II HDACs in causing this effect. Then, we investigated the possible relationship between DEHP-induced neuronal death and the post-translational mechanisms responsible for the down-regulation of Sp3. Interestingly, DEHP-induced Sp3 reduction was associated to its deacetylation and polyubiquitination. Co-immunoprecipitation studies showed that Sp3 physically interacted with HDAC4 after DEHP exposure, while HDAC4 inhibition by antisense oligodeoxynucleotide reverted the DEHP-induced degradation of Sp3. Notably, Sp3 overexpression was able to counteract the detrimental effect induced by DEHP. Taken together, these results suggest that DEHP exerts its toxic effect by inducing deacetylation of Sp3 via HDAC4, and afterwards, Sp3-polyubiquitination. PMID:25068794

Guida, Natascia; Laudati, Giusy; Galgani, Mario; Santopaolo, Marianna; Montuori, Paolo; Triassi, Maria; Di Renzo, Gianfranco; Canzoniero, Lorella M T; Formisano, Luigi

2014-10-01

307

The histone deacetylase inhibitor valproic acid sensitizes diffuse large B-cell lymphoma cell lines to CHOP-induced cell death  

PubMed Central

Epigenetic code modifications by histone deacetylase inhibitors (HDACis) have recently been proposed as potential new therapies for hematological malignancies. Diffuse large B-cell lymphoma (DLBCL) is the most common form of aggressive lymphoma. At present, standard first line treatment for DLBCL patients is the antracycline-based chemotherapy regimen CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) combined with the monoclonal anti-CD20 antibody rituximab (R-CHOP). Since only 50-60% of patients reach a long-time cure by this treatment, there is an urgent need for novel treatment strategies to increase the response and long-term remission to initial R-CHOP therapy. In this study, we investigated the effect of the HDAC inhibitor valproic acid (VPA) on DLBCL cell lines. To elucidate the effects of VPA on chemo-sensitivity, we used a cell-line based model of CHOP-refractory DLBCL. All five DLBCL cell lines treated with VPA alone or in combination with CHOP showed decreased viability and proliferation. The VPA-induced sensitization of DLBCL cells to cytotoxic treatment resulted in increased number of apoptotic cell as judged by annexin V-positivity and the presence of cleaved caspase-3. In addition, pretreatment with VPA resulted in a significantly increased DNA-damage as compared to CHOP alone. In summary, HDAC inhibitors such as VPA, are promising therapeutic agents in combination with R-CHOP for patients with DLBCL. PMID:23573362

Ageberg, Malin; Rydstrom, Karin; Relander, Thomas; Drott, Kristina

2013-01-01

308

Androgen receptor regulates nuclear trafficking and nuclear domain residency of corepressor HDAC7 in a ligand-dependent fashion  

SciTech Connect

In addition to chromosomal proteins, histone deacetylases (HDACs) target transcription factors in transcriptional repression. Here, we show that the class II HDAC family member HDAC7 is an efficient corepressor of the androgen receptor (AR). HDAC7 resided in the cytoplasm in the absence of AR or a cognate ligand, but hormone-occupancy of AR induced nuclear transfer of HDAC7. Nuclear colocalization pattern of AR and HDAC7 was dependent on the nature of the ligand. In the presence of testosterone, a portion of HDAC7 localized to pearl-like nuclear domains, whereas AR occupied with antagonistic ligands cyproterone acetate- or casodex (bicalutamide) recruited HDAC7 from these domains to colocalize with the receptor in speckles and nucleoplasm in a more complete fashion. Ectopic expression of PML-3 relieved the repressive effect of HDAC7 on AR function by sequestering HDAC7 to PML-3 domains. AR acetylation at Lys630/632/633 was not the target of HDAC7 repression, since repression of AR function was independent of these acetylation sites. Moreover, the deacetylase activity of HDAC7 was in part dispensable in the repression of AR function. In sum, our results identify HDAC7 as a novel AR corepressor whose subcellular and subnuclear compartmentalization can be regulated in an androgen-selective manner.

Karvonen, Ulla [Biomedicum Helsinki, Institute of Biomedicine, University of Helsinki, PO Box 63, FI-00014 Helsinki (Finland); Jaenne, Olli A. [Biomedicum Helsinki, Institute of Biomedicine, University of Helsinki, PO Box 63, FI-00014 Helsinki (Finland); Department of Clinical Chemistry, Helsinki University Central Hospital, FI-00290 Helsinki (Finland); Palvimo, Jorma J. [Biomedicum Helsinki, Institute of Biomedicine, University of Helsinki, PO Box 63, FI-00014 Helsinki (Finland) and Institute of Biomedicine/Medical Biochemistry, University of Kuopio, PO Box 1627, FI-70211 Kuopio (Finland)]. E-mail: jorma.palvimo@uku.fi

2006-10-01

309

Transcriptional modulation of monoaminergic neurotransmission genes by the histone deacetylase inhibitor trichostatin A in neuroblastoma cells.  

PubMed

Histone deacetylase inhibitors are promising anti-tumor agents partly due to their ability to disrupt the hypoxic signaling pathway in human malignancies. However, little is known about any effects of these drugs on the central nervous system. The aim of the present study was to analyze the effects of trichostatin A (TSA)--a broad-spectrum histone deacetylase inhibitor--on the transcriptional regulation of several genes involved in dopamine- and serotonergic neurotransmission. To this end, short-term parallel cultures of SK-NF-I neuroblastoma cells were treated with TSA either alone or in combination with hypoxia, and mRNA levels of dopamine receptor D3 (DRD3) and D4 (DRD4), dopamine transporter (DAT), dopamine hydroxylase (DBH), dopamine receptor regulating factor (DRRF), catechol-O-methyltransferase (COMT), serotonin receptor 1A (HTR1A), monoamino oxidase A (MAO-A), serotonin transporter (SLC6A4) and tryptophan hydroxylase 2 (TPH2) were determined by quantitative PCR. We found that TSA did not antagonize the hypoxia-induced activation of D3 and D4 dopamine receptor genes, implying that induction of these genes is not mediated directly by hypoxia inducible factor-1alpha. On the other hand, TSA dramatically upregulated the expression of DAT and SLC6A4 (45-fold and 15-fold, respectively), while transcript levels of MAO-A and COMT were significantly reduced (by 70% and by more than 90%, respectively). Induction of DAT protein expression was detected by western blotting. These results suggest that inhibition of histone deacetylases might help restore presynaptic monoamine pools via suppression of catecholamine breakdown and facilitation of monoamine reuptake in neurons. PMID:21785940

Bence, Melinda; Koller, Julia; Sasvari-Szekely, Maria; Keszler, Gergely

2012-01-01

310

Histone deacetylase inhibitor treatment induces 'BRCAness' and synergistic lethality with PARP inhibitor and cisplatin against human triple negative breast cancer cells.  

PubMed

There is an unmet need to develop new, more effective and safe therapies for the aggressive forms of triple negative breast cancers (TNBCs). While up to 20% of women under 50 years of age with TNBC harbor germline mutations in BRCA1, and these tumors are sensitive to treatment with poly(ADP) ribose polymerase inhibitors, a majority of TNBCs lack BRCA1 mutations or loss of expression. Findings presented here demonstrate that by attenuating the levels of DNA damage response and homologous recombination proteins, pan-histone deacetylase inhibitor (HDI) treatment induces 'BRCAness' and sensitizes TNBC cells lacking BRCA1 to lethal effects of PARP inhibitor or cisplatin. Treatment with HDI also induced hyperacetylation of nuclear hsp90. Similar effects were observed following shRNA-mediated depletion of HDAC3, confirming its role as the deacetylase for nuclear HSP90. Furthermore, cotreatment with HDI and ABT-888 induced significantly more DNA strand breaks than either agent alone, and synergistically induced apoptosis of TNBC cells. Notably, co-treatment with HDI and ABT-888 significantly reduced in vivo tumor growth and markedly improved the survival of mice bearing TNBC cell xenografts. These findings support the rationale to interrogate the clinical activity of this novel combination against human TNBC, irrespective of its expression of mutant BRCA1. PMID:25026298

Ha, Kyungsoo; Fiskus, Warren; Choi, Dong Soon; Bhaskara, Srividya; Cerchietti, Leandro; Devaraj, Santhana G T; Shah, Bhavin; Sharma, Sunil; Chang, Jenny C; Melnick, Ari M; Hiebert, Scott; Bhalla, Kapil N

2014-07-30

311

Histone deacetylase inhibitor, Trichostatin A induces ubiquitin-dependent cyclin D1 degradation in MCF-7 breast cancer cells  

PubMed Central

Background Cyclin D1 is an important regulator of G1-S phase cell cycle transition and has been shown to be important for breast cancer development. GSK3? phosphorylates cyclin D1 on Thr-286, resulting in enhanced ubiquitylation, nuclear export and degradation of the cyclin in the cytoplasm. Recent findings suggest that the development of small-molecule cyclin D1 ablative agents is of clinical relevance. We have previously shown that the histone deacetylase inhibitor trichostatin A (TSA) induces the rapid ubiquitin-dependent degradation of cyclin D1 in MCF-7 breast cancer cells prior to repression of cyclin D1 gene (CCND1) transcription. TSA treatment also resulted in accumulation of polyubiquitylated GFP-cyclin D1 species and reduced levels of the recombinant protein within the nucleus. Results Here we provide further evidence for TSA-induced ubiquitin-dependent degradation of cyclin D1 and demonstrate that GSK3?-mediated nuclear export facilitates this activity. Our observations suggest that TSA treatment results in enhanced cyclin D1 degradation via the GSK3?/CRM1-dependent nuclear export/26S proteasomal degradation pathway in MCF-7 cells. Conclusion We have demonstrated that rapid TSA-induced cyclin D1 degradation in MCF-7 cells requires GSK3?-mediated Thr-286 phosphorylation and the ubiquitin-dependent 26S proteasome pathway. Drug induced cyclin D1 repression contributes to the inhibition of breast cancer cell proliferation and can sensitize cells to CDK and Akt inhibitors. In addition, anti-cyclin D1 therapy may be highly specific for treating human breast cancer. The development of potent and effective cyclin D1 ablative agents is therefore of clinical relevance. Our findings suggest that HDAC inhibitors may have therapeutic potential as small-molecule cyclin D1 ablative agents. PMID:16504004

Alao, John P; Stavropoulou, Alexandra V; Lam, Eric W-F; Charles Coombes, R; Vigushin, David M

2006-01-01

312

3-Methylcholanthrene, an AhR Agonist, Caused Cell-Cycle Arrest by Histone Deacetylation through a RhoA-Dependent Recruitment of HDAC1 and pRb2 to E2F1 Complex  

PubMed Central

We previously showed that treating vascular endothelial cells with 3-methylcholanthrene (3MC) caused cell-cycle arrest in the Go/G1 phase; this resulted from the induction of p21 and p27 and a decreased level and activity of the cyclin-dependent kinase, Cdk2. We further investigated the molecular mechanisms that modulate cell-cycle regulatory proteins through the aryl-hydrocarbon receptor (AhR)/Ras homolog gene family, member A (RhoA) dependent epigenetic modification of histone. AhR/RhoA activation mediated by 3MC was essential for the upregulation of retinoblastoma 2 (pRb2) and histone deacetylase 1 (HDAC1), whereas their nuclear translocation was primarily modulated by RhoA activation. The combination of increased phosphatase and tensin homolog (PTEN) activity and decreased phosphatidylinositide 3-kinase (PI3K) activation by 3MC led to the inactivation of the Ras-cRaf pathway, which contributed to pRb2 hypophosphorylation. Increased HDAC1/pRb2 recruitment to the E2F1 complex decreased E2F1-transactivational activity and H3/H4 deacetylation, resulting in the downregulation of cell-cycle regulatory proteins (Cdk2/4 and Cyclin D3/E). Co-immunoprecipitation and electrophoretic mobility shift assay (EMSA) results showed that simvastatin prevented the 3MC-increased binding activities of E2F1 proteins in their promoter regions. Additionally, RhoA inhibitors (statins) reversed the effect of 3MC in inhibiting DNA synthesis by decreasing the nuclear translocation of pRb2/HDAC1, leading to a recovery of the levels of cell-cycle regulatory proteins. In summary, 3MC decreased cell proliferation by the epigenetic modification of histone through an AhR/RhoA-dependent mechanism that can be rescued by statins. PMID:24658119

Yang, Nian-Jie; Lee, Yi-Hsuan; Juan, Shu-Hui

2014-01-01

313

Myelodysplastic Syndrome and Histone Deacetylase Inhibitors: "To Be or Not to Be Acetylated"?  

PubMed Central

Myelodysplastic syndrome (MDS) represents a heterogeneous group of diseases with clonal proliferation, bone marrow failure and increasing risk of transformation into an acute myeloid leukaemia. Structured guidelines are developed for selective therapy based on prognostic subgroups, age, and performance status. Although many driving forces of disease phenotype and biology are described, the complete and possibly interacting pathogenetic pathways still remain unclear. Epigenetic investigations of cancer and haematologic diseases like MDS give new insights into the pathogenesis of this complex disease. Modifications of DNA or histones via methylation or acetylation lead to gene silencing and altered physiology relevant for MDS. First clinical trials give evidence that patients with MDS could benefit from epigenetic treatment with, for example, DNA methyl transferase inhibitors (DNMTi) or histone deacetylase inhibitors (HDACi). Nevertheless, many issues of HDACi remain incompletely understood and pose clinical and translational challenges. In this paper, major aspects of MDS, MDS-associated epigenetics and the potential use of HDACi are discussed. PMID:21629744

Stintzing, Sebastian; Kemmerling, Ralf; Kiesslich, Tobias; Alinger, Beate; Ocker, Matthias; Neureiter, Daniel

2011-01-01

314

?2-Adrenoceptor agonist dexmedetomidine protects septic acute kidney injury through increasing BMP-7 and inhibiting HDAC2 and HDAC5.  

PubMed

Bone morphogenetic protein (BMP)-7 protects sepsis-induced acute kidney injury (AKI). Dexmedetomidine (DEX), an ?(2)-adrenoceptor (?(2)-AR) agonist, has anti-inflammatory effects. We investigated the protective effects of DEX on sepsis-induced AKI and the expression of BMP-7 and histone deacetylases (HDACs). In vitro, the effects of DEX or trichostatin A (TSA, an HDAC inhibitor) on TNF-?, monocyte chemotactic protein (MCP-1), BMP-7, and HDAC mRNA expression in LPS-stimulated rat renal tubular epithelial NRK52E cells, was determined using real-time PCR. In vivo, mice were intraperitoneally injected with DEX (25 ?g/kg) or saline immediately and 12 h after cecal ligation and puncture (CLP) surgery. Twenty-four hours after CLP, we examined kidney injury and renal TNF-?, MCP-1, BMP-7, and HDAC expression. Survival was monitored for 120 h. LPS increased HDAC2, HDAC5, TNF-?, and MCP-1 expression, but decreased BMP-7 expression in NRK52E cells. DEX treatment decreased the HDAC2, HDAC5, TNF-?, and MCP-1 expression, but increased BMP-7 and acetyl histone H3 expression, whose effects were blocked by yohimbine, an ?(2)-AR antagonist. With DEX treatment, the LPS-induced TNF-? expression and cell death were attenuated in scRNAi-NRK52E but not BMP-7 RNAi-NRK52E cells. In CLP mice, DEX treatment increased survival and attenuated AKI. The expression of HDAC2, HDAC5, TNF-?, and MCP-1 mRNA in the kidneys of CLP mice was increased, but BMP-7 was decreased. However, DEX treatment reduced those changes. DEX reduces sepsis-induced AKI by decreasing TNF-? and MCP-1 and increasing BMP-7, which is associated with decreasing HDAC2 and HDAC5, as well as increasing acetyl histone H3. PMID:22933299

Hsing, Chung-Hsi; Lin, Chiou-Feng; So, Edmund; Sun, Ding-Ping; Chen, Tai-Chi; Li, Chien-Feng; Yeh, Ching-Hua

2012-11-15

315

Ubiquitin-dependent degradation of HDAC4, a new regulator of random cell motility  

PubMed Central

HDAC4 (histone deacetylase 4) belongs to class IIa of histone deacetylases, which groups important regulators of gene expression, controlling pleiotropic cellular functions. Here we show that, in addition to the well-defined nuclear/cytoplasmic shuttling, HDAC4 activity is modulated by the ubiquitin–proteasome system. Serum starvation elicits the poly-ubiquitination and degradation of HDAC4 in nontransformed cells. Phosphorylation of serine 298 within the PEST1 sequence plays an important role in the control of HDAC4 stability. Serine 298 lies within a glycogen synthase kinase 3? consensus sequence, and removal of growth factors fails to trigger HDAC4 degradation in cells deficient in this kinase. GSK3? can phosphorylate HDAC4 in vitro, and phosphorylation of serine 302 seems to play the role of priming phosphate. We have also found that HDAC4 modulates random cell motility possibly through the regulation of KLF2 transcription. Apoptosis, autophagy, cell proliferation, and growth arrest were unaffected by HDAC4. Our data suggest a link between regulation of HDAC4 degradation and the control of cell motility as operated by growth factors. PMID:21118993

Cernotta, Nadia; Clocchiatti, Andrea; Florean, Cristina; Brancolini, Claudio

2011-01-01

316

Reassessing the effects of histone deacetylase inhibitors on hippocampal memory and cognitive aging.  

PubMed

Converging results link histone acetylation dynamics to hippocampus-dependent memory, including evidence that histone deacetylase inhibitor (HDACi) administration enhances long-term memory. Previously, we demonstrated that aging disrupts the coordinated epigenetic response to recent experience observed in the young adult hippocampus. Here, we extended that work to test the cognitive effects of a novel, brain-penetrant HDACi (EVX001688; EVX) that we confirmed yields robust, relatively long lasting dose-dependent increases in histone acetylation in the hippocampus. In young rats, acute systemic EVX administration, scheduled to yield elevated histone acetylation levels during training in a contextual fear conditioning (CFC) task, had no effect on memory retention at 24 h at any dose examined (10, 30, or 60 mg/kg). Pretraining injection of another HDACi, sodium butyrate, also failed to affect fear memory, and CFC training itself had no influence on hippocampal histone acetylation at 1 hour in mice or two strains of rats. EVX administration before water maze training in young rats yielded a modest effect such that the middle dose produced marginally better 24-h retention than either the low or high dose, but only a small numerical benefit relative to vehicle. Guided by those findings, a final experiment tested the influence of pretraining EVX treatment on age-related spatial memory impairment. The results, revealing no effect on performance, are consistent with the idea that effective procognitive HDACi treatments in aging may require intervention aimed at restoring coordinated epigenetic regulation rather than bulk increases in hippocampal histone acetylation. PMID:24753063

Castellano, James F; Fletcher, Bonnie R; Patzke, Holger; Long, Jeffrey M; Sewal, Angila; Kim, David H; Kelley-Bell, Bennett; Rapp, Peter R

2014-08-01

317

Histone deacetylase inhibitors induce thymidine phosphorylase expression in cultured breast cancer cell lines.  

PubMed

Thymidine phosphorylase (TP) is an enzyme involved in thymidine synthesis and degradation. The expression of this enzyme has been proposed as a predictive factor for the therapeutic benefit of capecitabine, which is a precursor of the drug 5'-fluorouracil. In fact, TP is the rate-limiting enzyme in the activation of capecitabine. Therefore, higher levels of TP are expected to sensitize cancer cells to capecitabine treatment. In the present study, using breast cancer cell lines, we found a correlation between TP mRNA and protein levels, suggesting that compounds able to increase TP gene expression also increase protein levels. Accordingly, we demonstrated that treatment of breast cancer MCF7 and MDA231 cell lines with histone deacetylase inhibitors, tricostatin A and suberoylanilide hydroxamic acid, increased TP both at the mRNA and protein level. The effects of histone deacetylase inhibitors were not found to occur via the cytokine TNF?, a known inducer of TP expression. Our findings suggest a strategy to sensitize breast cancer cells to capecitabine treatment. PMID:21617864

Puppin, Cinzia; Puglisi, Fabio; Pandolfi, Maura; Di Loreto, Carla; Damante, Giuseppe

2011-08-01

318

Short-Chain Fatty Acids from Periodontal Pathogens Suppress Histone Deacetylases, EZH2, and SUV39H1 To Promote Kaposi's Sarcoma-Associated Herpesvirus Replication  

PubMed Central

ABSTRACT Periodontal pathogens such as Porphyromonas gingivalis and Fusobacterium nucleatum produce five different short-chain fatty acids (SCFAs) as metabolic by-products. We detect significantly higher levels of SCFAs in the saliva of patients with severe periodontal disease. The different SCFAs stimulate lytic gene expression of Kaposi's sarcoma-associated herpesvirus (KSHV) dose dependently and synergistically. SCFAs inhibit class-1/2 histone deacetylases (HDACs) and downregulate expression of silent information regulator-1 (SIRT1). SCFAs also downregulate expression of enhancer of zeste homolog2 (EZH2) and suppressor of variegation 3-9 homolog1 (SUV39H1), which are two histone N-lysine methyltransferases (HLMTs). By suppressing the different components of host epigenetic regulatory machinery, SCFAs increase histone acetylation and decrease repressive histone trimethylations to transactivate the viral chromatin. These new findings provide mechanistic support that SCFAs from periodontal pathogens stimulate KSHV replication and infection in the oral cavity and are potential risk factors for development of oral Kaposi's sarcoma (KS). IMPORTANCE About 20% of KS patients develop KS lesions first in the oral cavity, while other patients never develop oral KS. It is not known if the oral microenvironment plays a role in oral KS tumor development. In this work, we demonstrate that a group of metabolic by-products, namely, short-chain fatty acids, from bacteria that cause periodontal disease promote lytic replication of KSHV, the etiological agent associated with KS. These new findings provide mechanistic support that periodontal pathogens create a unique microenvironment in the oral cavity that contributes to KSHV replication and development of oral KS. PMID:24501407

Yu, Xiaolan; Shahir, Abdel-Malek; Sha, Jingfeng; Feng, Zhimin; Eapen, Betty; Nithianantham, Stanley; Das, Biswajit; Karn, Jonathan; Weinberg, Aaron; Bissada, Nabil F.

2014-01-01

319

The Synthesis and Evaluation of N1-(4-(2-[18F]-fluoroethyl)phenyl)-N8-hydroxyoctanediamide ([18F]-FESAHA), A PET Radiotracer Designed for the Delineation of Histone Deacetylase Expression in Cancer  

PubMed Central

Introduction Given the significant utility of suberoylanilide hydroxamic acid (SAHA) in chemotherapeutic protocols, a PET tracer that mimics the histone deacetylase (HDAC) inhibition of SAHA could be a valuable tool in the diagnosis, treatment planning, and treatment monitoring of cancer. Here, we describe the synthesis, characterization, and evaluation of N1-(4-(2-[18F]-fluoroethyl)phenyl)-N8-hydroxyoctanediamide ([18F]-FESAHA), a PET tracer designed for the delineation of HDAC expression in cancer. Methods FESAHA was synthesized and biologically characterized in vivo and in vitro. [18F]-FESAHA was then synthesized in high radiochemical purity, and the logP and serum stability of the radiotracer were determined. In vitro cellular uptake experiments and acute biodistribution and small animal PET studies were performed with [18F]-FESAHA in mice bearing LNCaP xenografts. Results [18F]-FESAHA was synthesized in high radiochemical purity via an innovative one-pot procedure. Enzymatic inhibition assays illustrated that FESAHA is a potent HDAC inhibitor, with IC50 values from 3 nM to 1.7 ?M against the eleven HDAC subtypes. Cell proliferation experiments revealed that the cytostatic properties of FESAHA very closely resemble those of SAHA in both LNCaP cells and PC-3 cells. Acute biodistribution and PET imaging experiments revealed tumor uptake of [18F]-FESAHA and substantially higher values in the small intestine, kidneys, liver, and bone. Conclusion The significant non-tumor background uptake of [18F]-FESAHA presents a substantial obstacle to the use of the radiotracer as an HDAC expression imaging agent. The study at hand, however, does present a number of lessons critical to both the synthesis of hydroxamic acid containing PET radiotracers and imaging agents aimed at delineating HDAC expression. PMID:21718944

Zeglis, Brian M.; Pillarsetty, NagaVara Kishore; Divilov, Vadim; Blasberg, Ronald A.; Lewis, Jason S.

2011-01-01

320

SMRT-mediated co-shuttling enables export of class IIa HDACs independent of their CaM kinase phosphorylation sites.  

PubMed

The Class IIa histone deacetylases (HDAC)4 and HDAC5 play a role in neuronal survival and behavioral adaptation in the CNS. Phosphorylation at 2/3 N-terminal sites promote their nuclear export. We investigated whether non-canonical signaling routes to Class IIa HDAC export exist because of their association with the co-repressor Silencing Mediator Of Retinoic And Thyroid Hormone Receptors (SMRT). We found that, while HDAC5 and HDAC4 mutants lacking their N-terminal phosphorylation sites (HDAC4(MUT), HDAC5(MUT)) are constitutively nuclear, co-expression with SMRT renders them exportable by signals that trigger SMRT export, such as synaptic activity, HDAC inhibition, and Brain Derived Neurotrophic Factor (BDNF) signaling. We found that SMRT's repression domain 3 (RD3) is critical for co-shuttling of HDAC5(MUT), consistent with the role for this domain in Class IIa HDAC association. In the context of BDNF signaling, we found that HDAC5(WT), which was more cytoplasmic than HDAC5(MUT), accumulated in the nucleus after BDNF treatment. However, co-expression of SMRT blocked BDNF-induced HDAC5(WT) import in a RD3-dependent manner. In effect, SMRT-mediated HDAC5(WT) export was opposing the BDNF-induced HDAC5 nuclear accumulation observed in SMRT's absence. Thus, SMRT's presence may render Class IIa HDACs exportable by a wider range of signals than those which simply promote direct phosphorylation. PMID:23083128

Soriano, Francesc X; Chawla, Sangeeta; Skehel, Paul; Hardingham, Giles E

2013-01-01

321

SMRT-mediated co-shuttling enables export of class IIa HDACs independent of their CaM kinase phosphorylation sites  

PubMed Central

The Class IIa histone deacetylases (HDAC)4 and HDAC5 play a role in neuronal survival and behavioral adaptation in the CNS. Phosphorylation at 2/3 N-terminal sites promote their nuclear export. We investigated whether non-canonical signaling routes to Class IIa HDAC export exist because of their association with the co-repressor Silencing Mediator Of Retinoic And Thyroid Hormone Receptors (SMRT). We found that, while HDAC5 and HDAC4 mutants lacking their N-terminal phosphorylation sites (HDAC4MUT, HDAC5MUT) are constitutively nuclear, co-expression with SMRT renders them exportable by signals that trigger SMRT export, such as synaptic activity, HDAC inhibition, and Brain Derived Neurotrophic Factor (BDNF) signaling. We found that SMRT's repression domain 3 (RD3) is critical for co-shuttling of HDAC5MUT, consistent with the role for this domain in Class IIa HDAC association. In the context of BDNF signaling, we found that HDAC5WT, which was more cytoplasmic than HDAC5MUT, accumulated in the nucleus after BDNF treatment. However, co-expression of SMRT blocked BDNF-induced HDAC5WT import in a RD3-dependent manner. In effect, SMRT-mediated HDAC5WT export was opposing the BDNF-induced HDAC5 nuclear accumulation observed in SMRT's absence. Thus, SMRT's presence may render Class IIa HDACs exportable by a wider range of signals than those which simply promote direct phosphorylation. PMID:23083128

Soriano, Francesc X; Chawla, Sangeeta; Skehel, Paul; Hardingham, Giles E

2013-01-01

322

Structure of HDAC3 bound to corepressor and inositol tetraphosphate  

PubMed Central

Summary Histone deacetylase enzymes (HDACs) are emerging cancer drug targets. They regulate gene expression by removing acetyl groups from lysine residues in histone tails resulting in chromatin condensation. The enzymatic activity of most class I HDACs requires recruitment to corepressor complexes. We report the first structure of an HDAC:corepressor complex - HDAC3 with the deacetylase-activation-domain (DAD) from the SMRT corepressor. The structure reveals two remarkable features. First the SMRT-DAD undergoes a large structural rearrangement on forming the complex. Second there is an essential inositol tetraphosphate molecule, Ins(1,4,5,6)P4, acting as an ‘intermolecular glue’ between the two proteins. Assembly of the complex is clearly dependent on the Ins(1,4,5,6)P4, which may act as a regulator – potentially explaining why inositol phosphates and their kinases have been found to act as transcriptional regulators. This mechanism for the activation of HDAC3 appears to be conserved in class I HDACs from yeast to man and opens novel therapeutic opportunities. PMID:22230954

Watson, Peter J.; Fairall, Louise; Santos, Guilherme M.; Schwabe, John W.R.

2011-01-01

323

Histone deacetylase inhibition rescues structural and functional brain deficits in a mouse model of Kabuki syndrome.  

PubMed

Kabuki syndrome is caused by haploinsufficiency for either of two genes that promote the opening of chromatin. If an imbalance between open and closed chromatin is central to the pathogenesis of Kabuki syndrome, agents that promote chromatin opening might have therapeutic potential. We have characterized a mouse model of Kabuki syndrome with a heterozygous deletion in the gene encoding the lysine-specific methyltransferase 2D (Kmt2d), leading to impairment of methyltransferase function. In vitro reporter alleles demonstrated a reduction in histone 4 acetylation and histone 3 lysine 4 trimethylation (H3K4me3) activity in mouse embryonic fibroblasts from Kmt2d(+/?Geo) mice. These activities were normalized in response to AR-42, a histone deacetylase inhibitor. In vivo, deficiency of H3K4me3 in the dentate gyrus granule cell layer of Kmt2d(+/?Geo) mice correlated with reduced neurogenesis and hippocampal memory defects. These abnormalities improved upon postnatal treatment with AR-42. Our work suggests that a reversible deficiency in postnatal neurogenesis underlies intellectual disability in Kabuki syndrome. PMID:25273096

Bjornsson, Hans T; Benjamin, Joel S; Zhang, Li; Weissman, Jacqueline; Gerber, Elizabeth E; Chen, Yi-Chun; Vaurio, Rebecca G; Potter, Michelle C; Hansen, Kasper D; Dietz, Harry C

2014-10-01

324

Copper induces histone hypoacetylation through directly inhibiting histone acetyltransferase activity.  

PubMed

The abnormal accumulation of Cu2+ is closely correlated with the incidence of different diseases, such as Alzheimer's disease and Wilson disease. To study in vivo functions of Cu2+ will lead to a better understanding of the nature of these diseases. In the present study, effect of Cu2+ on histone acetylation was investigated in human hepatoma cells. Exposure of cells to Cu2+ resulted in a significant decrease of histone acetylation, as indicated by the decrease of the overall histone acetylation and the decrease of histone H3 and H4 acetylation. Since histone acetyltransferase (HAT) and histone deacetylase (HDAC) are the enzymes controlled the state of histone acetylation in vivo, we tested their contribution to the inhibition of Cu2+ on histone acetylation. One hundred nanomolar trichostatin A, the specific inhibitor of HDAC, did not attenuate the inhibitory effect of Cu2+ on histone acetylation. Combined with that Cu2+ showed no effect on the in vitro activity of HDAC, these results led to the conclusion that it is HAT, but not HDAC that is involved in Cu2+ -induced histone hypoacetylation. This conclusion was confirmed by the facts that (1) Cu2+ significantly inhibited the in vitro activity of HAT, (2) Cu2+ -treated cells possessed a lower HAT activity than control cells, and (3) 50 or 100 microM bathocuproine disulfonate, a chelator of Cu2+, significantly attenuated the inhibition of Cu2+ on HAT activity and histone acetylation in the similar pattern. Combined with that Cu2+ showed no or obvious cytotoxicity at 100 or 200 microM in human hepatoma cells, and the previous study that Cu2+ inhibits the histone H4 acetylation of yeast cells at nontoxic or toxic levels, the data presented here suggest that inhibiting histone acetylation is probably one general in vivo function of Cu2+, where HAT is its molecular target. PMID:15276868

Kang, Jiuhong; Lin, Changjun; Chen, Jie; Liu, Qing

2004-07-20

325

Histone Deacetylase Inhibition Elicits an Evolutionarily Conserved Self-Renewal Program in Embryonic Stem Cells  

PubMed Central

SUMMARY Recent evidence indicates that mouse and human embryonic stem (ES) cells are fixed at different developmental stages, with the former positioned earlier. We show that a narrow concentration of the naturally occurring short chain fatty acid, sodium butyrate, supports the extensive self-renewal of mouse and human ES cells, while promoting their convergence toward an intermediate stem cell state. In response to butyrate human ES cells regress to an earlier developmental stage characterized by a gene expression profile resembling that of mouse ES cells, preventing precocious Xist expression, while retaining the ability to form complex teratomas in vivo. Other histone deacetylase inhibitors (HDACi) also support human ES cell self-renewal. Our results indicate that HDACi can promote ES cell self-renewal across species, and demonstrate that ES cells can toggle between alternative states in response to environmental factors. PMID:19341625

Ware, Carol B.; Wang, Linlin; Mecham, Brigham H.; Shen, Lanlan; Nelson, Angelique M.; Bar, Merav; Lamba, Deepak A.; Dauphin, Derek S.; Buckingham, Brian; Askari, Bardia; Lim, Raymond; Tewari, Muneesh; Gartler, Stanley M.; Issa, Jean-Pierre; Pavlidis, Paul; Duan, Zhijun; Blau, C. Anthony

2009-01-01

326

Histone deacetylase inhibitor sodium butyrate promotes the osteogenic differentiation of rat adipose-derived stem cells.  

PubMed

Adult stem cells hold great promise for use in tissue repair and regeneration. Recently, adipose tissue-derived stem cells (ADSCs) were found to be an appealing alternative to bone marrow stem cells (BMSCs) for bone tissue engineering. The main benefit of ADSCs is that they can be easily and abundantly available from adipose tissue. However, our prior study discovered an important phenomenon that BMSCs have greater osteogenic potential than ADSCs in vitro and epigenetic regulation plays a critical role in runt-related transcription factor 2 (Runx2) expression and thus osteogenesis. In this study, we aimed to improve the osteogenic potential of ADSCs by histone deacetylase inhibitor sodium butyrate (NaBu). We found that NaBu promoted rat ADSC osteogenic differentiation by altering the epigenetic modifications on the Runx2 promoter. PMID:24494796

Hu, Xiaoqing; Fu, Yutuo; Zhang, Xin; Dai, Linghui; Zhu, Jingxian; Bi, Zhenggang; Ao, Yingfang; Zhou, Chunyan

2014-04-01

327

USP22 transcriptional activity is negatively regulated by the histone deacetylase inhibitor trichostatin A.  

PubMed

The ubiquitin?specific protease 22 (USP22) gene is overexpressed in the majority of types of cancer cells, and has been implicated in tumorigenesis. However, the mechanisms that regulate its expression remain unclear. The results of the present study demonstrated that the expression of USP22 is negatively regulated by trichostatin A (TSA), a classical histone deacetylase inhibitor. Furthermore, TSA was revealed to interfere with the binding of RNA polymerase II to the USP22 promoter, directly suppressing its transcription. In addition, the overexpression of USP22 was observed to attenuate TSA?induced apoptosis in HeLa cells. To the best of our knowledge, these results provide the first insight into the regulation of the USP22 gene by antitumor drugs and into the mechanisms underlying the anticancer activity of TSA. PMID:25323692

Xiong, Jianjun; Xu, Xiaoyuan; Zhou, Xiaou; Liu, Jianyun; Gong, Zhen; Wu, Ping; Li, Weidong

2014-12-01

328

Up-Regulation of HDAC4 is Associated with Schwann Cell Proliferation After Sciatic Nerve Crush.  

PubMed

Histone deacetylase 4 (HDAC4), a member of the class IIa HDACs subfamily, has emerged as a critical regulator of cell growth, differentiation, and migration in various cell types. It was reported that HDAC4 stimulated colon cell proliferation via repression of p21. Also, HDAC4 contributes to platelet-derived growth factor-BB-induced proliferation and migration of vascular smooth muscle cells. Furthermore, HDAC4 may play an important role in the regulation of neuronal differentiation and survival. However, the role of HDAC4 in the process of peripheral nervous system regeneration after injury remains virtually unknown. Herein, we investigated the spatiotemporal expression of HDAC4 in a rat sciatic nerve crush model. We found that sciatic nerve crush induced up-regulated expression of HDAC4 in Schwann cells. Moreover, the expression of the proliferation marker Ki-67 exhibited a similar tendency with that of HDAC4. In cell cultures, we observed increased expression of HDAC4 during the process of TNF-?-induced Schwann cell proliferation, whereas the protein level of p21 was down-regulated. Interference of HDAC4 led to enhanced expression of p21 and impaired proliferation of Schwan cells. Taken together, our findings implicated that HDAC4 was up-regulated in the sciatic nerve after crush, which was associated with proliferation of Schwann cells. PMID:25103231

Liu, Yonghua; Liu, Yang; Nie, Xiaoke; Cao, Jianhua; Zhu, Xiaojian; Zhang, Weidong; Liu, Zhongbing; Mao, Xingxing; Yan, Shixian; Ni, Yingjie; Wang, Youhua

2014-11-01

329

HDAC4 protects cells from ER stress induced apoptosis through interaction with ATF4.  

PubMed

Histone deacetylase 4 (HDAC4) is involved in the regulation of many fundamental cell processes such as proliferation, differentiation, and survival via the modification of their substrates or protein-protein interactions. In this study, we found that HDAC4 could be upregulated under ER stress. There exists a direct interaction between HDAC4 and activating transcription factor 4 (ATF4). In vitro, overexpression of HDAC4 caused the retention of ATF4 in cytoplasm and inhibition of ATF4 transcriptional activity. ER stress could promote cell apoptosis through the upregulation of ATF4 levels and its target genes such as CHOP and TRB3. This effect was exacerbated by downregulation of HDAC4 levels. These results demonstrated that HDAC4 played an important role in the regulation of ER stress-induced apoptosis through interacting with ATF4 and inhibiting its transcriptional activity. PMID:24308964

Zhang, Pengfei; Sun, Qiao; Zhao, Chenyang; Ling, Shukuan; Li, Qi; Chang, Yan-Zhong; Li, Yingxian

2014-03-01

330

Histone Deacetylase Inhibitors for Treating a Spectrum of Diseases Not Related to Cancer  

PubMed Central

This issue of Molecular Medicine contains 14 original research reports and state-of-the-art reviews on histone deacetylase inhibitors (HDACi’s), which are being studied in models of a broad range of diseases not related to the proapoptotic properties used to treat cancer. The spectrum of these diseases responsive to HDACi’s is for the most part due to several antiinflammatory properties, often observed in vitro but importantly also in animal models. One unifying property is a reduction in cytokine production as well as inhibition of cytokine postreceptor signaling. Distinct from their use in cancer, the reduction in inflammation by HDACi’s is consistently observed at low concentrations compared with the higher concentrations required for killing tumor cells. This characteristic makes HDACi’s attractive candidates for treating chronic diseases, since low doses are well tolerated. For example, low oral doses of the HDACi givinostat have been used in children to reduce arthritis and are well tolerated. In addition to the antiinflammatory properties, HDACi’s have shown promise in models of neurodegenerative disorders, and HDACi’s also hold promise to drive HIV-1 out of latently infected cells. No one molecular mechanism accounts for the non–cancer-related properties of HDACi’s, since there are 18 genes coding for histone deacetylases. Rather, there are mechanisms unique for the pathological process of specific cell types. In this overview, we summarize the preclinical data on HDACi’s for therapy in a wide spectrum of diseases unrelated to the treatment of cancer. The data suggest the use of HDACi’s in treating autoimmune as well as chronic inflammatory diseases. PMID:21556484

Dinarello, Charles A; Fossati, Gianluca; Mascagni, Paolo

2011-01-01

331

Genetic control of developmental changes induced by disruption of Arabidopsis histone deacetylase 1 (AtHD1) expression.  

PubMed Central

Little is known about the role of genetic and epigenetic control in the spatial and temporal regulation of plant development. Overexpressing antisense Arabidopsis thaliana HD1 (AtHD1) encoding a putative major histone deacetylase induces pleiotropic effects on plant growth and development. It is unclear whether the developmental abnormalities are caused by a defective AtHD1 or related homologs and are heritable in selfing progeny. We isolated a stable antisense AtHD1 (CASH) transgenic line and a T-DNA insertion line in exon 2 of AtHD1, resulting in a null allele (athd1-t1). Both athd1-t1 and CASH lines display increased levels of histone acetylation and similar developmental abnormalities, which are heritable in the presence of antisense AtHD1 or in the progeny of homozygous (athd1-t1/athd1-t1) plants. Furthermore, when the athd1-t1/athd1-t1 plants are crossed to wild-type plants, the pleiotropic developmental abnormalities are immediately restored in the F(1) hybrids, which correlates with AtHD1 expression and reduction of histone H4 Lys12 acetylation. Unlike the situation with the stable code of DNA and histone methylation, developmental changes induced by histone deacetylase defects are immediately reversible, probably through the restoration of a reversible histone acetylation code needed for the normal control of gene regulation and development. PMID:14504245

Tian, Lu; Wang, Jianlin; Fong, M Paulus; Chen, Meng; Cao, Hongbin; Gelvin, Stanton B; Chen, Z Jeffrey

2003-01-01

332

Inhibition of HDAC2 Protects the Retina From Ischemic Injury  

PubMed Central

Purpose. Protein acetylation is an essential mechanism in regulating transcriptional and inflammatory events. Studies have shown that nonselective histone deacetylase (HDAC) inhibitors can protect the retina from ischemic injury in rats. However, the role of specific HDAC isoforms in retinal degenerative processes remains obscure. The purpose of this study was to investigate the role of HDAC2 isoform in a mouse model of ischemic retinal injury. Methods. Localization of HDAC2 in mice retinas was evaluated by immunohistochemical analyses. To investigate whether selective reduction in HDAC2 activity can protect the retina from ischemic injury, Hdac2+/? mice were utilized. Electroretinographic (ERG) and morphometric analyses were used to assess retinal function and morphology. Results. Our results demonstrated that HDAC2 is primarily localized in nuclei in inner nuclear and retinal ganglion cell layers, and HDAC2 activity accounted for approximately 35% of the total activities of HDAC1, 2, 3, and 6 in the retina. In wild-type mice, ERG a- and b-waves from ischemic eyes were significantly reduced when compared to pre-ischemia baseline values. Morphometric examination of these eyes revealed significant degeneration of inner retinal layers. In Hdac2+/? mice, ERG a- and b-waves from ischemic eyes were significantly greater than those measured in ischemic eyes from wild-type mice. Morphologic measurements demonstrated that Hdac2+/? mice exhibit significantly less retinal degeneration than wild-type mice. Conclusions. This study demonstrated that suppressing HDAC2 expression can effectively reduce ischemic retinal injury. Our results support the idea that the development of selective HDAC2 inhibitors may provide an efficacious treatment for ischemic retinal injury. PMID:23696608

Fan, Jie; Alsarraf, Oday; Dahrouj, Mohammad; Platt, Kenneth A.; Chou, C. James; Rice, Dennis S.; Crosson, Craig E.

2013-01-01

333

Class I-specific histone deacetylase inhibitor MS-275 overrides TRAIL-resistance in melanoma cells by downregulating c-FLIP.  

PubMed

Tumor-necrosis factor-related apoptosis-inducing ligand (TRAIL) has selective killing effect toward malignant cells; however some human melanomas are intrinsically resistant. In this study, we have shown that class I-specific histone deacetylase inhibitor (HDACi) MS-275 can synergize with TRAIL to induce apoptosis in TRAIL-resistant cell lines and to enhance susceptibility of sensitive cells. Conversely, class II-selective HDACi MC1575 has shown no effect on the resistance of melanoma cells and was able exclusively to increase TRAIL-induced cell death in responsive cells. Both the HDACis variably increased DR4, DR5, and procaspase 8 expression, regardless whether cells were TRAIL-sensitive or TRAIL-resistant. However, only MS-275 markedly decreased the expression levels of both the long and short c-FLIP isoforms. RNAi-mediated c-FLIP silencing resulted in caspase 8-dependent apoptosis in survivor cells which was comparable to that observed following MS-275 treatment. Accordingly, enforced expression of ectopic c-FLIP has abolished the cooperative induction of apoptosis by the combination of MS-275 and TRAIL. These data indicate that c-FLIP is a critical regulator of death ligand sensitivity in melanoma. Inhibition of class I HDAC isoenzymes 1, 2 and 3 has resulted to be functionally important for c-FLIP downregulation by MS-275. In contrast, knockdown of class II HDACs has had no effect on c-FLIP expression, thus explaining the dual incapacity of MC1575 to inhibit c-FLIP expression and sensitize cells resistant to TRAIL. The data reported here suggest that MS-275 represents a promising therapeutic approach in combination with TRAIL for treatment of cutaneous and uveal melanoma due to its ability to reduce c-FLIP expression. PMID:24946096

Venza, Isabella; Visalli, Maria; Oteri, Rosaria; Teti, Diana; Venza, Mario

2014-08-01

334

The anti-tumor histone deacetylase inhibitor SAHA and the natural flavonoid curcumin exhibit synergistic neuroprotection against amyloid-beta toxicity.  

PubMed

With the trend of an increasing aged population worldwide, Alzheimer's disease (AD), an age-related neurodegenerative disorder, as one of the major causes of dementia in elderly people is of growing concern. Despite the many hard efforts attempted during the past several decades in trying to elucidate the pathological mechanisms underlying AD and putting forward potential therapeutic strategies, there is still a lack of effective treatments for AD. The efficacy of many potential therapeutic drugs for AD is of main concern in clinical practice. For example, large bodies of evidence show that the anti-tumor histone deacetylase (HDAC) inhibitor, suberoylanilidehydroxamic acid (SAHA), may be of benefit for the treatment of AD; however, its extensive inhibition of HDACs makes it a poor therapeutic. Moreover, the natural flavonoid, curcumin, may also have a potential therapeutic benefit against AD; however, it is plagued by low bioavailability. Therefore, the integrative effects of SAHA and curcumin were investigated as a protection against amyloid-beta neurotoxicity in vitro. We hypothesized that at low doses their synergistic effect would improve therapeutic selectivity, based on experiments that showed that at low concentrations SAHA and curcumin could provide comprehensive protection against A?25-35-induced neuronal damage in PC12 cells, strongly implying potent synergism. Furthermore, network analysis suggested that the possible mechanism underlying their synergistic action might be derived from restoration of the damaged functional link between Akt and the CBP/p300 pathway, which plays a crucial role in the pathological development of AD. Thus, our findings provided a feasible avenue for the application of a synergistic drug combination, SAHA and curcumin, in the treatment of AD. PMID:24409332

Meng, Jia; Li, Yan; Camarillo, Cynthia; Yao, Yue; Zhang, Yina; Xu, Chun; Jiang, Lihong

2014-01-01

335

The Anti-Tumor Histone Deacetylase Inhibitor SAHA and the Natural Flavonoid Curcumin Exhibit Synergistic Neuroprotection against Amyloid-Beta Toxicity  

PubMed Central

With the trend of an increasing aged population worldwide, Alzheimer's disease (AD), an age-related neurodegenerative disorder, as one of the major causes of dementia in elderly people is of growing concern. Despite the many hard efforts attempted during the past several decades in trying to elucidate the pathological mechanisms underlying AD and putting forward potential therapeutic strategies, there is still a lack of effective treatments for AD. The efficacy of many potential therapeutic drugs for AD is of main concern in clinical practice. For example, large bodies of evidence show that the anti-tumor histone deacetylase (HDAC) inhibitor, suberoylanilidehydroxamic acid (SAHA), may be of benefit for the treatment of AD; however, its extensive inhibition of HDACs makes it a poor therapeutic. Moreover, the natural flavonoid, curcumin, may also have a potential therapeutic benefit against AD; however, it is plagued by low bioavailability. Therefore, the integrative effects of SAHA and curcumin were investigated as a protection against amyloid-beta neurotoxicity in vitro. We hypothesized that at low doses their synergistic effect would improve therapeutic selectivity, based on experiments that showed that at low concentrations SAHA and curcumin could provide comprehensive protection against A?25–35-induced neuronal damage in PC12 cells, strongly implying potent synergism. Furthermore, network analysis suggested that the possible mechanism underlying their synergistic action might be derived from restoration of the damaged functional link between Akt and the CBP/p300 pathway, which plays a crucial role in the pathological development of AD. Thus, our findings provided a feasible avenue for the application of a synergistic drug combination, SAHA and curcumin, in the treatment of AD. PMID:24409332

Camarillo, Cynthia; Yao, Yue; Zhang, Yina; Xu, Chun; Jiang, Lihong

2014-01-01

336

Histone Deacetylase Inhibition Downregulates Collagen 3A1 in Fibrotic Lung Fibroblasts  

PubMed Central

Idiopathic pulmonary fibrosis (IPF) is a deadly disease characterized by chronic inflammation and excessive collagen accumulation in the lung. Myofibroblasts are the primary collagen-producing cells in pulmonary fibrosis. Histone deacetylase inhibitor (HDACi) can affect gene expression, and some, such as suberoylanilide hydroxamic acid (SAHA), are US FDA approved for cancer treatment. In this study, we investigated SAHA’s effects on the expression of collagen III alpha 1 (COL3A1) in primary human IPF fibroblasts and in a murine model of pulmonary fibrosis. We observed that increased COL3A1 expression in IPF fibroblasts can be substantially reduced by SAHA treatment at the level of transcription as detected by RT-PCR; collagen III protein level was also reduced, as detected by Western blots and immunofluorescence. The deacetylation inhibitor effect of SAHA was verified by observing higher acetylation levels of both histone H3 and H4 in treated IPF cells. Chromatin immunoprecipitation (ChIP) experiments demonstrated that the reduced expression of COL3A1 by SAHA is with increased association of the repressive chromatin marker, H3K27Me3, and decreased association of the active chromatin marker, H3K9Ac. In our murine model of bleomycin-induced pulmonary fibrosis, the SAHA treated group demonstrated significantly less collagen III, as detected by immunohistochemistry. Our data indicate that the HDACi SAHA alters the chromatin associated with COL3A1, resulting in its decreased expression. PMID:24084714

Zhang, Xiangyu; Liu, Hui; Hock, Thomas; Thannickal, Victor J.; Sanders, Yan Y.

2013-01-01

337

Histone deacetylase inhibitors facilitate partner preference formation in female prairie voles  

PubMed Central

In the socially monogamous prairie vole (Microtus ochrogaster), mating induces enduring pair-bonds initiated by partner preference formation and regulated by a variety of neurotransmitters including oxytocin, vasopressin, and dopamine. Here we examined potential epigenetic mechanisms mediating pair-bond regulation. We show that the histone deacetylase inhibitors sodium butyrate and TrichoStatin A (TSA) facilitate partner preference formation in female prairie voles in the absence of mating. This was associated with a specific up-regulation of oxytocin (OTR) and vasopressin V1a receptors (V1aR) in the nucleus accumbens, through an increase in histone acetylation at their respective promoter. Furthermore, TSA-facilitated partner preference was prevented by OTR or V1aR blockade in the nucleus accumbens. Importantly, mating-induced partner preference triggered the same epigenetic regulation of OTR and V1aR gene promoters as TSA. These observations thus indicate that TSA and mating facilitate partner preference through epigenetic events, providing the first direct evidence for an epigenetic regulation of pair-bonding. PMID:23727821

Wang, Hui; Duclot, Florian; Liu, Yan; Wang, Zuoxin; Kabbaj, Mohamed

2013-01-01

338

Histone deacetylase inhibitors facilitate partner preference formation in female prairie voles.  

PubMed

In the socially monogamous prairie vole (Microtus ochrogaster), mating induces enduring pair-bonds that are initiated by partner preference formation and regulated by a variety of neurotransmitters, including oxytocin, vasopressin and dopamine. We examined potential epigenetic mechanisms mediating pair-bond regulation and found that the histone deacetylase inhibitors sodium butyrate and trichostatin A (TSA) facilitated partner preference formation in female prairie voles in the absence of mating. This was associated with a specific upregulation of oxytocin receptor (OTR, oxtr) and vasopressin V1a receptor (V1aR, avpr1a) in the nucleus accumbens (NAcc), through an increase in histone acetylation at their respective promoters. Furthermore, TSA-facilitated partner preference was prevented by OTR or V1aR blockade in the NAcc. Notably, mating-induced partner preference triggered the same epigenetic regulation of oxtr and avpr1a gene promoters as TSA. These observations indicate that TSA and mating facilitate partner preference through epigenetic events, providing, to the best of our knowledge, the first direct evidence for epigenetic regulation of pair-bonding. PMID:23727821

Wang, Hui; Duclot, Florian; Liu, Yan; Wang, Zuoxin; Kabbaj, Mohamed

2013-07-01

339

Mule determines the apoptotic response to HDAC inhibitors by targeted ubiquitination and destruction of HDAC2  

PubMed Central

Histone deacetylases (HDACs) are major epigenetic modulators involved in a broad spectrum of human diseases including cancers. Administration of HDAC inhibitors (HDACis) leads to growth inhibition, differentiation, and apoptosis of cancer cells. Understanding the regulatory mechanism of HDACs is imperative to harness the therapeutic potentials of HDACis. Here we show that HDACi- and DNA damage-induced apoptosis are severely compromised in mouse embryonic fibroblasts lacking a HECT domain ubiquitin ligase, Mule (Mcl-1 ubiquitin ligase E3). Mule specifically targets HDAC2 for ubiquitination and degradation. Accumulation of HDAC2 in Mule-deficient cells leads to compromised p53 acetylation as well as crippled p53 transcriptional activation, accumulation, and apoptotic response upon DNA damage and Nutlin-3 treatments. These defects in Mule-null cells can be partially reversed by HDACis and fully rescued by lowering the elevated HDAC2 in Mule-null cells to the normal levels as in wild-type cells. Taken together, our results reveal a critical regulatory mechanism of HDAC2 by Mule and suggest this pathway determines the cellular response to HDACis and DNA damage. PMID:22016339

Zhang, Jing; Kan, Shu; Huang, Brian; Hao, Zhenyue; Mak, Tak W.; Zhong, Qing

2011-01-01

340

Inhibition of phosphatidylinositol 3-kinase\\/Akt and histone deacetylase activity induces apoptosis in non-small cell lung cancer in vitro and in vivo  

Microsoft Academic Search

Objective: Resistance to histone deacetylase inhibitors in non-small cell lung cancer is mediated in part through activation of nuclear factor-B through a phosphatidyl- inositol 3-kinase\\/Akt- dependent pathway. We hypothesize that inhibition of phos- phatidylinositol 3-kinase\\/Akt will sensitize non-small cell lung cancer cells to histone deacetylase inhibitor-induced apoptosis. Methods: Tumorigenic non-small cell lung cancer cell lines H157, H358, H460, and A549

Chadrick E. Denlinger; Brian K. Rundall; David R. Jones

2010-01-01

341

Utility of a Histone Deacetylase Inhibitor (PXD101) for Thyroid Cancer Treatment  

PubMed Central

Background We evaluated the therapeutic effects of the histone deacetylase inhibitor PXD101 alone and in combination with conventional chemotherapy in treating thyroid cancer. Methodology/Principal Findings We studied eight cell lines from four types of thyroid cancer (papillary, follicular, anaplastic and medullary). The cytotoxicity of PXD101 alone and in combination with three conventional chemotherapeutic agents (doxorubicin, paclitaxel and docetaxel) was measured using LDH assay. Western blot assessed express