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Sample records for hdac histone deacetylase

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

    PubMed Central

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

    2003-01-01

    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

  2. Induction of histone deacetylases (HDACs) in human abdominal aortic aneurysm: therapeutic potential of HDAC inhibitors

    PubMed Central

    Galán, María; Varona, Saray; Orriols, Mar; Rodríguez, José Antonio; Aguiló, Silvia; Dilmé, Jaume; Camacho, Mercedes; Martínez-González, José; Rodriguez, Cristina

    2016-01-01

    ABSTRACT Clinical management of abdominal aortic aneurysm (AAA) is currently limited to elective surgical repair because an effective pharmacotherapy is still awaited. Inhibition of histone deacetylase (HDAC) activity could be a promising therapeutic option in cardiovascular diseases. We aimed to characterise HDAC expression in human AAA and to evaluate the therapeutic potential of class I and IIa HDAC inhibitors in the AAA model of angiotensin II (Ang II)-infused apolipoprotein-E-deficient (ApoE−/−) mice. Real-time PCR, western blot and immunohistochemistry evidenced an increased expression of HDACs 1, 2 (both class I), 4 and 7 (both class IIa) in abdominal aorta samples from patients undergoing AAA open repair (n=22) compared with those from donors (n=14). Aortic aneurysms from Ang-II-infused ApoE−/− mice exhibited a similar HDAC expression profile. In these animals, treatment with a class I HDAC inhibitor (MS-275) or a class IIa inhibitor (MC-1568) improved survival, reduced the incidence and severity of AAA and limited aneurysmal expansion evaluated by Doppler ultrasonography. These beneficial effects were more potent in MC-1568-treated mice. The disorganisation of elastin and collagen fibres and lymphocyte and macrophage infiltration were effectively reduced by both inhibitors. Additionally, HDAC inhibition attenuated the exacerbated expression of pro-inflammatory markers and the increase in metalloproteinase-2 and -9 activity induced by Ang II in this model. Therefore, our data evidence that HDAC expression is deregulated in human AAA and that class-selective HDAC inhibitors limit aneurysm expansion in an AAA mouse model. New-generation HDAC inhibitors represent a promising therapeutic approach to overcome human aneurysm progression. PMID:26989193

  3. Histone Deacetylase (HDAC) Inhibitors - Emerging Roles in Neuronal Memory, Learning, Synaptic Plasticity and Neural Regeneration

    PubMed Central

    Ahmad Ganai, Shabir; Ramadoss, Mahalakshmi; Mahadevan, Vijayalakshmi

    2016-01-01

    Epigenetic regulation of neuronal signalling through histone acetylation dictates transcription programs that govern neuronal memory, plasticity and learning paradigms. Histone Acetyl Transferases (HATs) and Histone Deacetylases (HDACs) are antagonistic enzymes that regulate gene expression through acetylation and deacetylation of histone proteins around which DNA is wrapped inside a eukaryotic cell nucleus. The epigenetic control of HDACs and the cellular imbalance between HATs and HDACs dictate disease states and have been implicated in muscular dystrophy, loss of memory, neurodegeneration and autistic disorders. Altering gene expression profiles through inhibition of HDACs is now emerging as a powerful technique in therapy. This review presents evolving applications of HDAC inhibitors as potential drugs in neurological research and therapy. Mechanisms that govern their expression profiles in neuronal signalling, plasticity and learning will be covered. Promising and exciting possibilities of HDAC inhibitors in memory formation, fear conditioning, ischemic stroke and neural regeneration have been detailed. PMID:26487502

  4. Histone deacetylase 3 (HDAC 3) as emerging drug target in NF-κB-mediated inflammation

    PubMed Central

    Leus, Niek G.J.; Zwinderman, Martijn R.H.; Dekker, Frank J.

    2016-01-01

    Activation of inflammatory gene expression is regulated, among other factors, by post-translational modifications of histone proteins. The most investigated type of histone modifications are lysine acetylations. Histone deacetylases (HDACs) remove acetylations from lysines, thereby influencing (inflammatory) gene expression. Intriguingly, apart from histones, HDACs also target non-histone proteins. The nuclear factor κB (NF-κB) pathway is an important regulator in the expression of numerous inflammatory genes, and acetylation plays a crucial role in regulating its responses. Several studies have shed more light on the role of HDAC 1-3 in inflammation with a particular pro-inflammatory role for HDAC 3. Nevertheless, the HDAC-NF-κB interactions in inflammatory signalling have not been fully understood. An important challenge in targeting the regulatory role of HDACs in the NF-κB pathway is the development of highly potent small molecules that selectively target HDAC iso-enzymes. This review focuses on the role of HDAC 3 in (NF-κB-mediated) inflammation and NF-κB lysine acetylation. In addition, we address the application of frequently used small molecule HDAC inhibitors as an approach to attenuate inflammatory responses, and their potential as novel therapeutics. Finally, recent progress and future directions in medicinal chemistry efforts aimed at HDAC 3-selective inhibitors are discussed. PMID:27371876

  5. Histone Deacetylases

    PubMed Central

    Parbin, Sabnam; Kar, Swayamsiddha; Shilpi, Arunima; Sengupta, Dipta; Deb, Moonmoon; Rath, Sandip Kumar

    2014-01-01

    In the current era of genomic medicine, diseases are identified as manifestations of anomalous patterns of gene expression. Cancer is the principal example among such maladies. Although remarkable progress has been achieved in the understanding of the molecular mechanisms involved in the genesis and progression of cancer, its epigenetic regulation, particularly histone deacetylation, demands further studies. Histone deacetylases (HDACs) are one of the key players in the gene expression regulation network in cancer because of their repressive role on tumor suppressor genes. Higher expression and function of deacetylases disrupt the finely tuned acetylation homeostasis in both histone and non-histone target proteins. This brings about alterations in the genes implicated in the regulation of cell proliferation, differentiation, apoptosis and other cellular processes. Moreover, the reversible nature of epigenetic modulation by HDACs makes them attractive targets for cancer remedy. This review summarizes the current knowledge of HDACs in tumorigenesis and tumor progression as well as their contribution to the hallmarks of cancer. The present report also describes briefly various assays to detect histone deacetylase activity and discusses the potential role of histone deacetylase inhibitors as emerging epigenetic drugs to cure cancer. PMID:24051359

  6. Histone deacetylase 3 (HDAC3) as a novel therapeutic target in multiple myeloma

    PubMed Central

    Minami, Jiro; Suzuki, Rikio; Mazitschek, Ralph; Gorgun, Gullu; Ghosh, Balaram; Cirstea, Diana; Hu, Yiguo; Mimura, Naoya; Ohguchi, Hiroto; Cottini, Francesca; Jakubikova, Jana; Munshi, Nikhil C.; Haggarty, Stephen J.; Richardson, Paul G.; Hideshima, Teru; Anderson, Kenneth C.

    2014-01-01

    Histone deacetylases (HDACs) represent novel molecular targets for the treatment of various types of cancers, including multiple myeloma (MM). Many HDAC inhibitors have already shown remarkable anti-tumor activities in the preclinical setting; however, their clinical utility is limited due to unfavorable toxicities associated with their broad range HDAC inhibitory effects. Isoform-selective HDAC inhibition may allow for MM cytotoxicity without attendant side effects. In this study, we demonstrated that HDAC3 knockdown and a small molecule HDAC3 inhibitor BG45 trigger significant MM cell growth inhibition via apoptosis, evidenced by caspase and PARP cleavage. Importantly, HDAC3 inhibition downregulates phosphorylation (tyrosine 705 and serine 727) of STAT3. Neither IL-6 nor bone marrow stromal cells overcome this inhibitory effect of HDAC3 inhibition on p-STAT3 and MM cell growth. Moreover, HDAC3 inhibition also triggers hyperacetylation of STAT3, suggesting crosstalk signaling between phosphorylation and acetylation of STAT3. Importantly, inhibition of HDAC3, but not HDAC1 or HDAC2, significantly enhances bortezomib-induced cytotoxicity. Finally, we confirm that BG45 alone and in combination with bortezomib trigger significant tumor growth inhibition in vivo in a murine xenograft model of human MM. Our results indicate that HDAC3 represents a promising therapeutic target, and validate a prototype novel HDAC3 inhibitor BG45 in MM. PMID:23913134

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

    PubMed Central

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

    2014-01-01

    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

  8. Synthesis and Biological Investigation of Oxazole Hydroxamates as Highly Selective Histone Deacetylase 6 (HDAC6) Inhibitors.

    PubMed

    Senger, Johanna; Melesina, Jelena; Marek, Martin; Romier, Christophe; Oehme, Ina; Witt, Olaf; Sippl, Wolfgang; Jung, Manfred

    2016-02-25

    Histone deacetylase 6 (HDAC6) catalyzes the removal of an acetyl group from lysine residues of several non-histone proteins. Here we report the preparation of thiazole-, oxazole-, and oxadiazole-containing biarylhydroxamic acids by a short synthetic procedure. We identified them as selective HDAC6 inhibitors by investigating the inhibition of recombinant HDAC enzymes and the protein acetylation in cells by Western blotting (tubulin vs histone acetylation). The most active compounds exhibited nanomolar potency and high selectivity for HDAC6. For example, an oxazole hydroxamate inhibits HDAC6 with an IC50 of 59 nM and has a selectivity index of >200 against HDAC1 and HDAC8. This is the first report showing that the nature of a heterocycle directly connected to a zinc binding group (ZBG) can be used to modulate subtype selectivity and potency for HDAC6 inhibitors to such an extent. We rationalize the high potency and selectivity of the oxazoles by molecular modeling and docking.

  9. In Vivo Imaging of Histone Deacetylases (HDACs) in the Central Nervous System and Major Peripheral Organs

    PubMed Central

    2015-01-01

    Epigenetic enzymes are now targeted to treat the underlying gene expression dysregulation that contribute to disease pathogenesis. Histone deacetylases (HDACs) have shown broad potential in treatments against cancer and emerging data supports their targeting in the context of cardiovascular disease and central nervous system dysfunction. Development of a molecular agent for non-invasive imaging to elucidate the distribution and functional roles of HDACs in humans will accelerate medical research and drug discovery in this domain. Herein, we describe the synthesis and validation of an HDAC imaging agent, [11C]6. Our imaging results demonstrate that this probe has high specificity, good selectivity, and appropriate kinetics and distribution for imaging HDACs in the brain, heart, kidney, pancreas, and spleen. Our findings support the translational potential for [11C]6 for human epigenetic imaging. PMID:25203558

  10. Inhibitors of histone deacetylase (HDAC) restore the p53 pathway in neuroblastoma cells

    PubMed Central

    Condorelli, F; Gnemmi, I; Vallario, A; Genazzani, A A; Canonico, P L

    2007-01-01

    Background and purpose: Inhibitors of histone deacetylase (HDAC) are emerging as a promising class of anti-cancer drugs, but a generic deregulation of transcription in neoplastic cells cannot fully explain their therapeutic effects. In this study we evaluated alternative molecular mechanisms by which HDAC inhibitors could affect neuroblastoma viability. Experimental approach: Effects of HDAC inhibitors on survival of the I-type SK-N-BE and the N-type NB SH-SY5Y neuroblastoma cell lines were assessed by the MTT assay. Molecular pathways leading to this were examined by western blot, confocal microscopy and cytofluorometry. The mRNA levels of apoptotic mediators were assessed semi-quantitatively by RT-PCR. Tumour-suppressor p53 trans activity was assessed in EMSA experiments. HDAC inhibitors were also studied in cells subjected to plasmid-based p53 interference (p53i). Key results: HDAC inhibitors induced cell death via the mitochondrial pathway of apoptosis with recruitment of Bcl-2 family members. Bcl-2 overexpression rendered neuroblastoma cells resistant to HDAC inhibitor treatment. Low concentrations of HDAC inhibitors (0.9 mM) caused a G2 cell-cycle arrest and a marked upregulation of the p21/Waf1/Cip1 protein. HDAC inhibitors also activate the p53 protein via hyper-acetylation and nuclear re-localization, without affecting its protein expression. Accordingly, HDAC inhibitor-induced cell-killing and p21/Waf1/Cip1 upregulation is impaired in p53i-cells. Conclusions and implications: In neuroblastoma cells, HDAC inhibitors may overcome the resistance to classical chemotherapeutic drugs by restoring the p53 tumour-repressor function via its hyper-acetylation and nuclear migration, events usually impaired in such tumours. In neuroblastoma cells, HDAC inhibitors are not able to induce p21/Waf1/Cip1 in the absence of a functional p53. PMID:18059320

  11. The role of class I histone deacetylase (HDAC) on gluconeogenesis in liver

    SciTech Connect

    Oiso, Hiroshi; Furukawa, Noboru; Suefuji, Mihoshi; Shimoda, Seiya; Ito, Akihiro; Furumai, Ryohei; Nakagawa, Junichi; Yoshida, Minoru; Nishino, Norikazu; Araki, Eiichi

    2011-01-07

    Research highlights: {yields} A novel class I HDAC inhibitor decreased hepatic PEPCK mRNA and gluconeogenesis. {yields} Inhibition of HDAC decreased PEPCK by reducing HNF4{alpha} expression and FoxO1 activity. {yields} siRNA knockdown of HDAC1 in HepG2 cells reduced the expression of PEPCK and HNF4{alpha}. {yields} Inhibition of class I HDAC improves glucose homeostasis in HFD mice. -- Abstract: Hepatic gluconeogenesis is crucial for glucose homeostasis. Although sirtuin 1 (Sirt1) is implicated in the regulation of gluconeogenesis in the liver, the effects of other histone deacetylases (HDAC) on gluconeogenesis are unclear. The aim of this study was to identify the role of class I HDACs in hepatic gluconeogenesis. In HepG2 cells and the liver of mice, the expressions of phosphoenol pyruvate carboxykinase (PEPCK) and hepatocyte nuclear factor 4{alpha} (HNF4{alpha}) were significantly decreased by treatment with a newly designed class I HDAC inhibitor, Ky-2. SiRNA knockdown of HDAC1 expression, but not of HDAC2 or HDAC3, in HepG2 cells decreased PEPCK and HNF4{alpha} expression. In HepG2 cells, insulin-stimulated phosphorylation of Akt and forkhead box O 1 (FoxO1) was increased by Ky-2. Pyruvate tolerance tests in Ky-2-treated high-fat-diet (HFD)-fed mice showed a marked reduction in blood glucose compared with vehicle-treated HFD mice. These data suggest that class I HDACs increase HNF4{alpha} protein expression and the transcriptional activity of FoxO1, followed by the induction of PEPCK mRNA expression and gluconeogenesis in liver.

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

    PubMed Central

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

    2013-01-01

    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

  13. HDAC2 blockade by nitric oxide and histone deacetylase inhibitors reveals a common target in Duchenne muscular dystrophy treatment

    PubMed Central

    Colussi, Claudia; Mozzetta, Chiara; Gurtner, Aymone; Illi, Barbara; Rosati, Jessica; Straino, Stefania; Ragone, Gianluca; Pescatori, Mario; Zaccagnini, Germana; Antonini, Annalisa; Minetti, Giulia; Martelli, Fabio; Piaggio, Giulia; Gallinari, Paola; Steinkuhler, Christian; Clementi, Emilio; Dell'Aversana, Carmela; Altucci, Lucia; Mai, Antonello; Capogrossi, Maurizio C.; Puri, Pier Lorenzo; Gaetano, Carlo

    2008-01-01

    The overlapping histological and biochemical features underlying the beneficial effect of deacetylase inhibitors and NO donors in dystrophic muscles suggest an unanticipated molecular link among dystrophin, NO signaling, and the histone deacetylases (HDACs). Higher global deacetylase activity and selective increased expression of the class I histone deacetylase HDAC2 were detected in muscles of dystrophin-deficient MDX mice. In vitro and in vivo siRNA-mediated down-regulation of HDAC2 in dystrophic muscles was sufficient to replicate the morphological and functional benefits observed with deacetylase inhibitors and NO donors. We found that restoration of NO signaling in vivo, by adenoviral-mediated expression of a constitutively active endothelial NOS mutant in MDX muscles, and in vitro, by exposing MDX-derived satellite cells to NO donors, resulted in HDAC2 blockade by cysteine S-nitrosylation. These data reveal a special contribution of HDAC2 in the pathogenesis of Duchenne muscular dystrophy and indicate that HDAC2 inhibition by NO-dependent S-nitrosylation is important for the therapeutic response to NO donors in MDX mice. They also define a common target for independent pharmacological interventions in the treatment of Duchenne muscular dystrophy. PMID:19047631

  14. HDAC2 blockade by nitric oxide and histone deacetylase inhibitors reveals a common target in Duchenne muscular dystrophy treatment.

    PubMed

    Colussi, Claudia; Mozzetta, Chiara; Gurtner, Aymone; Illi, Barbara; Rosati, Jessica; Straino, Stefania; Ragone, Gianluca; Pescatori, Mario; Zaccagnini, Germana; Antonini, Annalisa; Minetti, Giulia; Martelli, Fabio; Piaggio, Giulia; Gallinari, Paola; Steinkuhler, Christian; Steinkulher, Christian; Clementi, Emilio; Dell'Aversana, Carmela; Altucci, Lucia; Mai, Antonello; Capogrossi, Maurizio C; Puri, Pier Lorenzo; Gaetano, Carlo

    2008-12-09

    The overlapping histological and biochemical features underlying the beneficial effect of deacetylase inhibitors and NO donors in dystrophic muscles suggest an unanticipated molecular link among dystrophin, NO signaling, and the histone deacetylases (HDACs). Higher global deacetylase activity and selective increased expression of the class I histone deacetylase HDAC2 were detected in muscles of dystrophin-deficient MDX mice. In vitro and in vivo siRNA-mediated down-regulation of HDAC2 in dystrophic muscles was sufficient to replicate the morphological and functional benefits observed with deacetylase inhibitors and NO donors. We found that restoration of NO signaling in vivo, by adenoviral-mediated expression of a constitutively active endothelial NOS mutant in MDX muscles, and in vitro, by exposing MDX-derived satellite cells to NO donors, resulted in HDAC2 blockade by cysteine S-nitrosylation. These data reveal a special contribution of HDAC2 in the pathogenesis of Duchenne muscular dystrophy and indicate that HDAC2 inhibition by NO-dependent S-nitrosylation is important for the therapeutic response to NO donors in MDX mice. They also define a common target for independent pharmacological interventions in the treatment of Duchenne muscular dystrophy.

  15. Differential effects of binge methamphetamine injections on the mRNA expression of histone deacetylases (HDACs) in the rat striatum

    PubMed Central

    Omonijo, Oluwaseyi; Wongprayoon, Pawaris; Ladenheim, Bruce; McCoy, Michael T.; Govitrapong, Piyarat; Jayanthi, Subramaniam; Cadet, Jean Lud

    2014-01-01

    Methamphetamine use disorder is characterized by recurrent binge episodes. Humans addicted to methamphetamine experience various degrees of cognitive deficits and show evidence of neurodegenerative processes in the brain. Binge injections of METH to rodents also cause significant toxic changes in the brain. In addition, this pattern of METH injections can alter gene expression in the dorsal striatum. Gene expression is regulated, in part, by histone deacetylation. We thus tested the possibility that METH toxic doses might cause changes in the mRNA levels of histone deacetylases (HDACs). We found that METH did produce significant decreases in the mRNA expression of HDAC8, which is a class I HDAC. METH also decreased expression of HDAC6, HDAC9, and HDAC10 that are class II HDACs. The expression of the class IV HDAC, HDAC11, was also suppressed by METH. The expression of Sirt2, Sirt5, and Sirt6 that are members of class III HDACs was also downregulated by METH injections. Our findings implicate changes in HDAC expression may be an early indicator of impending METH-induced neurotoxicity in the striatum. This idea is consistent with the accumulated evidence that some HDACs are involved in neurodegenerative processes in the brain. PMID:25452209

  16. Histone deacetylase 6 (HDAC6) deacetylates survivin for its nuclear export in breast cancer.

    PubMed

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

    2012-03-30

    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.

  17. The Effects of Pharmacological Inhibition of Histone Deacetylase 3 (HDAC3) in Huntington’s Disease Mice

    PubMed Central

    Jia, Haiqun; Wang, Ying; Morris, Charles D.; Jacques, Vincent; Gottesfeld, Joel M.; Rusche, James R.; Thomas, Elizabeth A.

    2016-01-01

    An important epigenetic modification in Huntington’s disease (HD) research is histone acetylation, which is regulated by histone acetyltransferase and histone deacetylase (HDAC) enzymes. HDAC inhibitors have proven effective in HD model systems, and recent work is now focused on functional dissection of the individual HDAC enzymes in these effects. Histone deacetylase 3 (HDAC3), a member of the class I subfamily of HDACs, has previously been implicated in neuronal toxicity and huntingtin-induced cell death. Hence, we tested the effects of RGFP966 ((E)-N-(2-amino-4-fluorophenyl)-3-(1-cinnamyl-1H-pyrazol-4-yl)acrylamide), a benzamide-type HDAC inhibitor that selectively targets HDAC3, in the N171-82Q transgenic mouse model of HD. We found that RGFP966 at doses of 10 and 25 mg/kg improves motor deficits on rotarod and in open field exploration, accompanied by neuroprotective effects on striatal volume. In light of previous studies implicating HDAC3 in immune function, we measured gene expression changes for 84 immune-related genes elicited by RGFP966 using quantitative PCR arrays. RGFP966 treatment did not cause widespread changes in cytokine/chemokine gene expression patterns, but did significantly alter the striatal expression of macrophage migration inhibitory factor (Mif), a hormone immune modulator associated with glial cell activation, in N171-82Q transgenic mice, but not WT mice. Accordingly, RGFP966-treated mice showed decreased glial fibrillary acidic protein (GFAP) immunoreactivity, a marker of astrocyte activation, in the striatum of N171-82Q transgenic mice compared to vehicle-treated mice. These findings suggest that the beneficial actions of HDAC3 inhibition could be related, in part, with lowered Mif levels and its associated downstream effects. PMID:27031333

  18. Type-specific roles of histone deacetylase (HDAC) overexpression in ovarian carcinoma: HDAC1 enhances cell proliferation and HDAC3 stimulates cell migration with downregulation of E-cadherin.

    PubMed

    Hayashi, Akiko; Horiuchi, Akiko; Kikuchi, Norihiko; Hayashi, Takuma; Fuseya, Chiho; Suzuki, Akihisa; Konishi, Ikuo; Shiozawa, Tanri

    2010-09-01

    Histone acetylation/deacetylation controls chromatin activity and subsequent gene transcription. Recent studies demonstrated the activation of histone deacetylases (HDACs) in various human malignancies; however, the expression and function of HDACs in ovarian tumors are not fully understood. In this study, we examined the immunohistochemical expression of HDAC1, HDAC2 and HDAC3 using tissues obtained from 115 cases of ovarian tumors and compared it with that of Ki-67 (a growth marker), p21, and E-cadherin and clinicopathological parameters. In addition, we analyzed the effect of specific siRNA for HDAC1, HDAC2 and HDAC3 on the expression of cell cycle-related molecules and E-cadherin to clarify the functional difference among the 3 HDACs. The results indicated that the immunohistochemical expression of nuclear HDAC1, HDAC2 and HDAC3 proteins increased stepwise in benign, borderline and malignant tumors. The expression of HDAC1 and HDAC2 was correlated with Ki-67 expression and that of HDAC3 was inversely correlated with E-cadherin expression. Among the HDACs examined, only HDAC1 was associated with a poor outcome, when overexpressed. Treatment with HDAC inhibitors suppressed the proliferation of ovarian cancer cells in association with apoptosis. A specific siRNA for HDAC1 significantly reduced the proliferation of ovarian carcinoma cells via downregulation of cyclin A expression, but siRNA for HDAC3 reduced the cell migration with elevated E-cadherin expression. Our results suggested that HDAC1 plays an important role in the proliferation of ovarian cancer cells, whereas HDAC3 functions in cell adhesion and migration. Therefore, specific therapeutic approaches should be considered according to the HDAC subtypes.

  19. Inhibition of Histone Deacetylase 3 (HDAC3) Mediates Ischemic Preconditioning and Protects Cortical Neurons against Ischemia in Rats

    PubMed Central

    Wu, Qimei; Zhang, Lei; Feng, Linyin

    2016-01-01

    Brain ischemic preconditioning (PC) provides vital insights into the endogenous protection against stroke. Genomic and epigenetic responses to PC condition the brain into a state of ischemic tolerance. Notably, PC induces the elevation of histone acetylation, consistent with evidence that histone deacetylase (HDAC) inhibitors protect the brain from ischemic injury. However, less is known about the specific roles of HDACs in this process. HDAC3 has been implicated in several neurodegenerative conditions. Deletion of HDAC3 confers protection against neurotoxicity and neuronal injury. Here, we hypothesized that inhibition of HDAC3 may contribute to the neuronal survival elicited by PC. To address this notion, PC and transient middle cerebral artery occlusion (MCAO) were conducted in Sprague-Dawley rats. Additionally, primary cultured cortical neurons were used to identify the modulators and effectors of HDAC3 involved in PC. We found that nuclear localization of HDAC3 was significantly reduced following PC in vivo and in vitro. Treatment with the HDAC3-specific inhibitor, RGFP966, mimicked the neuroprotective effects of PC 24 h and 7 days after MCAO, causing a reduced infarct volume and less Fluoro-Jade C staining. Improved functional outcomes were observed in the neurological score and rotarod test. We further showed that attenuated recruitment of HDAC3 to promoter regions following PC potentiates transcriptional initiation of genes including Hspa1a, Bcl2l1, and Prdx2, which may underlie the mechanism of protection. In addition, PC-activated calpains were implicated in the cleavage of HDAC3. Pretreatment with calpeptin blockaded the attenuated nuclear distribution of HDAC3 and the protective effect of PC in vivo. Collectively, these results demonstrate that the inhibition of HDAC3 preconditions the brain against ischemic insults, indicating a new approach to evoke endogenous protection against stroke. PMID:27965534

  20. Histone deacetylase (HDAC) inhibitor kinetic rate constants correlate with cellular histone acetylation but not transcription and cell viability.

    PubMed

    Lauffer, Benjamin E L; Mintzer, Robert; Fong, Rina; Mukund, Susmith; Tam, Christine; Zilberleyb, Inna; Flicke, Birgit; Ritscher, Allegra; Fedorowicz, Grazyna; Vallero, Roxanne; Ortwine, Daniel F; Gunzner, Janet; Modrusan, Zora; Neumann, Lars; Koth, Christopher M; Lupardus, Patrick J; Kaminker, Joshua S; Heise, Christopher E; Steiner, Pascal

    2013-09-13

    Histone deacetylases (HDACs) are critical in the control of gene expression, and dysregulation of their activity has been implicated in a broad range of diseases, including cancer, cardiovascular, and neurological diseases. HDAC inhibitors (HDACi) employing different zinc chelating functionalities such as hydroxamic acids and benzamides have shown promising results in cancer therapy. Although it has also been suggested that HDACi with increased isozyme selectivity and potency may broaden their clinical utility and minimize side effects, the translation of this idea to the clinic remains to be investigated. Moreover, a detailed understanding of how HDACi with different pharmacological properties affect biological functions in vitro and in vivo is still missing. Here, we show that a panel of benzamide-containing HDACi are slow tight-binding inhibitors with long residence times unlike the hydroxamate-containing HDACi vorinostat and trichostatin-A. Characterization of changes in H2BK5 and H4K14 acetylation following HDACi treatment in the neuroblastoma cell line SH-SY5Y revealed that the timing and magnitude of histone acetylation mirrored both the association and dissociation kinetic rates of the inhibitors. In contrast, cell viability and microarray gene expression analysis indicated that cell death induction and changes in transcriptional regulation do not correlate with the dissociation kinetic rates of the HDACi. Therefore, our study suggests that determining how the selective and kinetic inhibition properties of HDACi affect cell function will help to evaluate their therapeutic utility.

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

    PubMed

    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

    2014-07-08

    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.

  2. Histone Deacetylase Inhibitor Phenylbutyrate Exaggerates Heart Failure in Pressure Overloaded Mice independently of HDAC inhibition

    PubMed Central

    Ma, Jing; Luo, Tao; Zeng, Zhi; Fu, Haiying; Asano, Yoshihiro; Liao, Yulin; Minamino, Tetsuo; Kitakaze, Masafumi

    2016-01-01

    4-Sodium phenylbutyrate (PBA) has been reported to inhibit endoplasmic reticulum stress and histone deacetylation (HDAC), both of which are novel therapeutic targets for cardiac hypertrophy and heart failure. However, it is unclear whether PBA can improve heart function. Here, we tested the effects of PBA and some other HDAC inhibitors on cardiac dysfunction induced by pressure overload. Transverse aortic constriction (TAC) was performed on male C57BL/6 mice. PBA treatment (100 mg/kg, 6 weeks) unexpectedly led to a higher mortality, exacerbated cardiac remodelling and dysfunction. Similar results were noted in TAC mice treated with butyrate sodium (BS), a PBA analogue. In contrast, other HDAC inhibitors, valproic acid (VAL) and trichostatin A (TSA), improved the survival. All four HDAC inhibitors induced histone H3 acetylation and inhibited HDAC total activity. An individual HDAC activity assay showed that rather than class IIa members (HDAC4 and 7), PBA and BS predominantly inhibited class I members (HDAC2 and 8), whereas VAL and TSA inhibited all of them. These findings indicate that PBA and BS accelerate cardiac hypertrophy and dysfunction, whereas VAL and TSA have opposing effects. PMID:27667442

  3. Histone deacetylases and atherosclerosis.

    PubMed

    Zheng, Xia-xia; Zhou, Tian; Wang, Xin-An; Tong, Xiao-hong; Ding, Jia-wang

    2015-06-01

    Atherosclerosis is the most common pathological process that leads to cardiovascular diseases, a disease of large- and medium-sized arteries that is characterized by a formation of atherosclerotic plaques consisting of necrotic cores, calcified regions, accumulated modified lipids, smooth muscle cells (SMCs), endothelial cells, leukocytes, and foam cells. Recently, the question about how to suppress the occurrence of atherosclerosis and alleviate the progress of cardiovascular disease becomes the hot topic. Accumulating evidence suggests that histone deacetylases(HDACs) play crucial roles in arteriosclerosis. This review summarizes the effect of HDACs and HDAC inhibitors(HDACi) on the progress of atherosclerosis.

  4. Ketamine produces antidepressant-like effects through phosphorylation-dependent nuclear export of histone deacetylase 5 (HDAC5) in rats

    PubMed Central

    Choi, Miyeon; Lee, Seung Hoon; Wang, Sung Eun; Ko, Seung Yeon; Song, Mihee; Choi, June-Seek; Duman, Ronald S.; Son, Hyeon

    2015-01-01

    Ketamine produces rapid antidepressant-like effects in animal assays for depression, although the molecular mechanisms underlying these behavioral actions remain incomplete. Here, we demonstrate that ketamine rapidly stimulates histone deacetylase 5 (HDAC5) phosphorylation and nuclear export in rat hippocampal neurons through calcium/calmodulin kinase II- and protein kinase D-dependent pathways. Consequently, ketamine enhanced the transcriptional activity of myocyte enhancer factor 2 (MEF2), which leads to regulation of MEF2 target genes. Transfection of a HDAC5 phosphorylation-defective mutant (Ser259/Ser498 replaced by Ala259/Ala498, HDAC5-S/A), resulted in resistance to ketamine-induced nuclear export, suppression of ketamine-mediated MEF2 transcriptional activity, and decreased expression of MEF2 target genes. Behaviorally, viral-mediated hippocampal knockdown of HDAC5 blocked or occluded the antidepressant effects of ketamine both in unstressed and stressed animals. Taken together, our results reveal a novel role of HDAC5 in the actions of ketamine and suggest that HDAC5 could be a potential mechanism contributing to the therapeutic actions of ketamine. PMID:26647181

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

    PubMed Central

    2011-01-01

    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

  6. The interplay between G protein-coupled receptor kinase 2 (GRK2) and histone deacetylase 6 (HDAC6) at the crossroads of epithelial cell motility

    PubMed Central

    Lafarga, Vanesa; Mayor, Jr, Federico; Penela, Petronila

    2012-01-01

    G protein-coupled receptor kinase 2 (GRK2) is emerging as a key integrative node in cell migration control. In addition to its canonical role in the desensitization of G protein-coupled receptors involved in chemotaxis, novel recently identified GRK2 substrates and interacting partners appear to mediate the GRK2-dependent modulation of diverse molecular processes involved in motility, such as gradient sensing, cell polarity or cytoskeletal reorganization. We have recently identified an interaction between GRK2 and histone deacetylase 6 (HDAC6), a major cytoplasmic α-tubulin deacetylase involved in cell motility and adhesion. GRK2 dynamically associates with and phosphorylates HDAC6 to stimulate its α-tubulin deacetylase activity at specific cellular localizations such as the leading edge of migrating cells, thus promoting local tubulin deacetylation and enhanced motility. This GRK2-HDAC6 functional interaction may have important implications in pathological contexts related to aberrant epithelial cell migration. PMID:23076141

  7. Histone Deacetylases and Cardiometabolic Diseases

    PubMed Central

    Yiew, Kan Hui; Chatterjee, Tapan K.; Hui, David Y.; Weintraub, Neal L.

    2015-01-01

    Cardiometabolic disease, emerging as a worldwide epidemic, is a combination of metabolic derangements leading to type 2 diabetes and cardiovascular disease. Genetic and environmental factors are linked through epigenetic mechanisms to the pathogenesis of cardiometabolic disease. Post-translational modifications of histone tails, including acetylation and deacetylation, epigenetically alter chromatin structure and dictate cell-specific gene expression patterns. The histone deacetylase (HDAC) family is comprised of 18 members that regulate gene expression by altering the acetylation status of nucleosomal histones and by functioning as nuclear transcriptional co-repressors. HDACs regulate key aspects of metabolism, inflammation, and vascular function pertinent to cardiometabolic disease in a cell- and tissue-specific manner. HDACs also likely play a role in the “metabolic memory” of diabetes, an important clinical aspect of the disease. Understanding the molecular, cellular, and physiological functions of HDACs in cardiometabolic disease is expected to provide insight into disease pathogenesis, risk factor control, and therapeutic development. PMID:26183616

  8. Acetylation of retinal histones in diabetes increases inflammatory proteins: effects of minocycline and manipulation of histone acetyltransferase (HAT) and histone deacetylase (HDAC).

    PubMed

    Kadiyala, Chandra Sekhar Rao; Zheng, Ling; Du, Yunpeng; Yohannes, Elizabeth; Kao, Hung-Ying; Miyagi, Masaru; Kern, Timothy S

    2012-07-27

    Histone acetylation was significantly increased in retinas from diabetic rats, and this acetylation was inhibited in diabetics treated with minocycline, a drug known to inhibit early diabetic retinopathy in animals. Histone acetylation and expression of inflammatory proteins that have been implicated in the pathogenesis of diabetic retinopathy were increased likewise in cultured retinal Müller glia grown in a diabetes-like concentration of glucose. Both the acetylation and induction of the inflammatory proteins in elevated glucose levels were significantly inhibited by inhibitors of histone acetyltransferase (garcinol and antisense against the histone acetylase, p300) or activators of histone deacetylase (theophylline and resveratrol) and were increased by the histone deacetylase inhibitor, suberolylanilide hydroxamic acid. We conclude that hyperglycemia causes acetylation of retinal histones (and probably other proteins) and that the acetylation contributes to the hyperglycemia-induced up-regulation of proinflammatory proteins and thereby to the development of diabetic retinopathy.

  9. Large-Scale Overproduction and Purification of Recombinant Histone Deacetylase 8 (HDAC8) from the Human-Pathogenic Flatworm Schistosoma mansoni.

    PubMed

    Marek, Martin; Shaik, Tajith B; Duclaud, Sylvie; Pierce, Raymond J; Romier, Christophe

    2016-01-01

    Epigenetic mechanisms underlie the morphological transformations and shifts in virulence of eukaryotic pathogens. The targeting of epigenetics-driven cellular programs thus represents an Achilles' heel of human parasites. Today, zinc-dependent histone deacetylases (HDACs) belong to the most explored epigenetic drug targets in eukaryotic parasites. Here, we describe an optimized protocol for the large-scale overproduction and purification of recombinant smHDAC8, an emerging epigenetic drug target in the multicellular human-pathogenic flatworm Schistosoma mansoni. The strategy employs the robustness of recombinant expression in Escherichia coli together with initial purification through a poly-histidine affinity tag that can be removed by the thrombin protease. This protocol is divided into two steps: (1) large-scale production of smHDAC8 in E. coli, and (2) purification of the target smHDAC8 protein through multiple purification steps.

  10. Inactivation of histone deacetylase 1 (HDAC1) but not HDAC2 is required for the glucocorticoid-dependent CCAAT/enhancer-binding protein α (C/EBPα) expression and preadipocyte differentiation.

    PubMed

    Kuzmochka, Claire; Abdou, Houssein-Salem; Haché, Robert J G; Atlas, Ella

    2014-12-01

    Several drugs currently used in the management of mood disorders, epilepsy (ie, valproic acid), or the control of inflammation (ie, corticosteroids) have been shown to promote visceral obesity in humans by increasing the number of newly formed adipocytes. Valproic acid is classified as a nonspecific histone deacetylase (HDAC) inhibitor, along with trichostatin A and butyric acid. In vitro experiments have demonstrated that such molecules greatly enhance the rate of preadipocyte differentiation, similarly to the effect of corticosteroids. The glucocorticoid receptor stimulates adipogenesis in part by enhancing the transcription of C/ebpa through the titration, and subsequent degradation, of HDAC1 from the C/ebpα promoter. There is, however, controversy in the literature as to the role of HDACs during adipogenesis. In this study, we sought to demonstrate, using 2 different strategies, the definite role of HDAC1 in adipogenesis. By using small interference RNA-mediated knockdown of HDAC1 and by generating an enzymatically inactive HDAC1D181A by site-directed mutagenesis, we were able to show that HDAC1, but not HDAC2, suppresses glucocorticoid receptor-potentiated preadipocyte differentiation by decreasing CCAAT/enhancer-binding protein (C/ebp)α and Pparγ expression levels at the onset of differentiation. Finally, we demonstrate that HDAC1D181A acts as a dominant negative mutant of HDAC1 during adipogenesis by modulating C/EBPβ transcriptional activity on the C/ebpα promoter.

  11. Potent, Selective, and CNS-Penetrant Tetrasubstituted Cyclopropane Class IIa Histone Deacetylase (HDAC) Inhibitors

    PubMed Central

    2015-01-01

    Potent and selective class IIa HDAC tetrasubstituted cyclopropane hydroxamic acid inhibitors were identified with high oral bioavailability that exhibited good brain and muscle exposure. Compound 14 displayed suitable properties for assessment of the impact of class IIa HDAC catalytic site inhibition in preclinical disease models. PMID:26819662

  12. The histone deacetylase inhibitor valproic acid inhibits NKG2D expression in natural killer cells through suppression of STAT3 and HDAC3

    PubMed Central

    Ni, Lulu; Wang, Lixin; Yao, Chao; Ni, Zhongya; Liu, Fei; Gong, Chenyuan; Zhu, Xiaowen; Yan, Xuewei; Watowich, Stephanie S.; Lee, Dean A.; Zhu, Shiguo

    2017-01-01

    NKG2D is a major activating receptor of NK cells and plays a critical role in tumor immunosurveillance. NKG2D expression in NK cells is inhibited by the histone deacetylase (HDAC) inhibitor valproic acid (VPA) and enhanced by the narrow-spectrum HDAC inhibitor entinostat. We previously demonstrated that entinostat enhanced NKG2D transcription by increasing acetylation of Histones H3 and H4. However, the mechanism by which VPA reduces NKG2D expression in NK cells is not known. We have also shown that NKG2D transcription is regulated by STAT3 phosphorylation. In this study, we investigated regulation of NKG2D expression in NK cells by VPA and entinostat by assessing protein expression, phosphorylation, and interaction of HDACs and STAT3. We find that VPA selectively inhibits STAT3 tyrosine705 phosphorylation, but entinostat does not. STAT3 complexes with HDAC3, and HDAC3 inhibition represses STAT3 phosphorylation and therefore NKG2D expression. NK cells from STAT3 wild-type mice downregulate NKG2D in response to VPA, but not NK cells from STAT3 knockout mice. These results show that VPA is a potent inhibitor of STAT3 phosphorylation and demonstrate that histone acetylation and STAT3 tyrosine705 phosphorylation cooperate in regulating NKG2D expression in NK cells. PMID:28338101

  13. Liver-enriched inhibitory protein (LIP) actively inhibits preadipocyte differentiation through histone deacetylase 1 (HDAC1).

    PubMed

    Abdou, Houssein-Salem; Atlas, Ella; Haché, Robert J G

    2011-06-17

    The CCAAT/enhancer-binding protein β (C/EBPβ) is expressed as three isoforms (LAP*, liver-enriched activating protein (LAP), and liver-enriched inhibitory protein (LIP)) that differentially regulate gene expression. The interplay between LAP*, LAP, and LIP in regulating cellular processes is largely unknown, and LIP has been largely regarded to repress transcription through a passive heterodimerization-dependent mechanism. Recently, we have shown that p300/GCN5 and mSin3A/HDAC1 differentially regulate the ability of C/EBPβ to stimulate preadipocyte differentiation through activation of C/ebpα transcription. Here, we have mapped requirements for binding of mSin3A/HDAC1 to LAP/LAP* and LIP to a 4-amino acid motif in the central region of LAP/LAP* (residues 153-156) and the N terminus of LIP. Reducing mSin3A/HDAC1 binding to LAP/LAP* and LIP through deletion of this motif reduced the recruitment of HDAC1 to the C/ebpα promoter and increased preadipocyte differentiation stimulated by insulin and 1-methyl-3-isobutylxanthine. Additional studies showed that the interaction of HDAC1 with LIP provides for active repression of C/ebpα transcription and is largely responsible for the ability of LIP and HDAC1 to repress preadipocyte differentiation. Thus, although mSin3A/HDAC1 interacted readily with LAP/LAP* in addition to LIP and that expression of LAP/LAP* was sufficient to recruit HDAC1 to the C/ebpα promoter, mutations in C/ebpβ that abrogated HDAC1 association to LAP/LAP* in the absence of LIP provided no additional stimulation of differentiation or transcription beyond the deletion of LIP alone. The implication of these results for the interaction between p300/GCN5 and mSin3A/HDAC1 in regulating C/EBPα transcription and preadipocyte differentiation are discussed.

  14. A NOVEL ROLE FOR HISTONE DEACETYLASE 6 (HDAC6) IN THE REGULATION OF THE TOLEROGENIC STAT3/IL-10 PATHWAY IN ANTIGEN PRESENTING CELLS

    PubMed Central

    Cheng, Fengdong; Lienlaf, Maritza; Wang, Hong-Wei; Perez-Villarroel, Patricio; Lee, Calvin; Woan, Karrune; Rock-Klotz, Jennifer; Sahakian, Eva; Woods, David; Pinilla-Ibarz, Javier; Kalin, Jay; Tao, Jianguo; Hancock, Wayne; Kozikowski, Alan; Seto, Edward; Villagra, Alejandro; Sotomayor, Eduardo M.

    2014-01-01

    Antigen-presenting cells (APCs) are critical in T-cell activation and in the induction of T-cell tolerance. Epigenetic modifications of specific genes in the APC play a key role in this process, and among them, histone deacetylases (HDACs) have emerged as key participants. HDAC6, one of the members of this family of enzymes, has been shown to be involved in regulation of inflammatory and immune responses. Here we show for the first time, that genetic or pharmacologic disruption of HDAC6 in macrophages and dendritic cells resulted in diminished production of the immunosuppressive cytokine IL-10, and induction of inflammatory APCs that effectively activate antigen-specific naïve T-cells and restore the responsiveness of anergic CD4+ T-cells. Mechanistically, we have found that HDAC6 forms a previously unknown molecular complex with STAT3, association that was detected in both the cytoplasmic and nuclear compartments of the APC. By using HDAC6 recombinant mutants we identified the domain comprising aminoacids 503-840 as being required for HDAC6 interaction with STAT3. Furthermore, by re-chromatin immunoprecipitation we confirmed that HDAC6 and STAT3 are both recruited to the same DNA sequence within the Il10 gene promoter. Of note, disruption of this complex by knocking down HDAC6 resulted in decreased STAT3 phosphorylation -but no changes in STAT3 acetylation- as well as diminished recruitment of STAT3 to the Il10 gene promoter region. The additional demonstration that a selective HDAC6 inhibitor disrupts this STAT3/IL-10 tolerogenic axis points to HDAC6 as a novel molecular target in APCs to overcome immune tolerance and tips the balance towards T-cell immunity. PMID:25108026

  15. Studies of benzamide- and thiol-based histone deacetylase inhibitors in models of oxidative-stress-induced neuronal death: identification of some HDAC3-selective inhibitors.

    PubMed

    Chen, Yufeng; He, Rong; Chen, Yihua; D'Annibale, Melissa A; Langley, Brett; Kozikowski, Alan P

    2009-05-01

    We compare three structurally different classes of histone deacetylase (HDAC) inhibitors that contain benzamide, hydroxamate, or thiol groups as the zinc binding group (ZBG) for their ability to protect cortical neurons in culture from cell death induced by oxidative stress. This study reveals that none of the benzamide-based HDAC inhibitors (HDACIs) provides any neuroprotection whatsoever, in distinct contrast to HDACIs that contain other ZBGs. Some of the sulfur-containing HDACIs, namely the thiols, thioesters, and disulfides present modest neuroprotective activity but show toxicity at higher concentrations. Taken together, these data demonstrate that the HDAC6-selective mercaptoacetamides that were reported previously provide the best protection in the homocysteic acid model of oxidative stress, thus further supporting their study in animal models of neurodegenerative diseases.

  16. Design, synthesis and biological evaluation of thienopyrimidine hydroxamic acid based derivatives as structurally novel histone deacetylase (HDAC) inhibitors.

    PubMed

    Wang, Jiang; Su, Mingbo; Li, Tingting; Gao, Anhui; Yang, Wei; Sheng, Li; Zang, Yi; Li, Jia; Liu, Hong

    2017-03-10

    New thienopyrimidine hydroxamic acid derivatives as HDACs inhibitors were designed, synthesized and evaluated. All compounds were evaluated for their ability to inhibit recombinant human HDAC1, HDAC3, and HDAC6 isoforms and in vitro anti-proliferative activity on tumor cell lines RMPI 8226 and HCT 116. Most of these compounds displayed good to excellent inhibitory activities against HDACs. The IC50 values of compound 9m against HDAC1, HDAC3, and HDAC6 was 29.81 ± 0.52 nM, 24.71 ± 1.16 nM, and 21.29 ± 0.32 nM. Most of these compounds showed strong anti-proliferative activity against human cancer cell lines including RMPI 8226 and HCT 116. The IC50 values of compound 9m against RPMI 8226 and HCT 116 proliferation were 0.97 ± 0.072 μM and 1.01 ± 0.033 μM, respectively. In addition, compound 9m noticeably up-regulated the level of histone H3 acetylation at the low concentration of 0.3 μM.

  17. Erasers of Histone Acetylation: The Histone Deacetylase Enzymes

    PubMed Central

    Seto, Edward; Yoshida, Minoru

    2014-01-01

    Histone deacetylases (HDACs) are enzymes that catalyze the removal of acetyl functional groups from the lysine residues of both histone and nonhistone proteins. In humans, there are 18 HDAC enzymes that use either zinc- or NAD+-dependent mechanisms to deacetylate acetyl lysine substrates. Although removal of histone acetyl epigenetic modification by HDACs regulates chromatin structure and transcription, deacetylation of nonhistones controls diverse cellular processes. HDAC inhibitors are already known potential anticancer agents and show promise for the treatment of many diseases. PMID:24691964

  18. Histone Deacetylase 3 (HDAC3)-dependent Reversible Lysine Acetylation of Cardiac Myosin Heavy Chain Isoforms Modulates Their Enzymatic and Motor Activity*

    PubMed Central

    Samant, Sadhana A.; Pillai, Vinodkumar B.; Sundaresan, Nagalingam R.; Shroff, Sanjeev G.; Gupta, Mahesh P.

    2015-01-01

    Reversible lysine acetylation is a widespread post-translational modification controlling the activity of proteins in different subcellular compartments. We previously demonstrated that a class II histone deacetylase (HDAC), HDAC4, and a histone acetyltransferase, p300/CREB-binding protein-associated factor, associate with cardiac sarcomeres and that a class I and II HDAC inhibitor, trichostatin A, enhances contractile activity of myofilaments. In this study we show that a class I HDAC, HDAC3, is also present at cardiac sarcomeres. By immunohistochemical and electron microscopic analyses, we found that HDAC3 was localized to A-band of sarcomeres and capable of deacetylating myosin heavy chain (MHC) isoforms. The motor domains of both cardiac α- and β-MHC isoforms were found to be reversibly acetylated. Biomechanical studies revealed that lysine acetylation significantly decreased the Km for the actin-activated ATPase activity of MHC isoforms. By in vitro motility assay, we found that lysine acetylation increased the actin-sliding velocity of α-myosin by 20% and β-myosin by 36% compared with their respective non-acetylated isoforms. Moreover, myosin acetylation was found to be sensitive to cardiac stress. During induction of hypertrophy, myosin isoform acetylation increased progressively with duration of stress stimuli independently of isoform shift, suggesting that lysine acetylation of myosin could be an early response of myofilaments to increase contractile performance of the heart. These studies provide the first evidence for localization of HDAC3 at myofilaments and uncover a novel mechanism modulating the motor activity of cardiac MHC isoforms. PMID:25911107

  19. Histone Deacetylase 3 (HDAC3)-dependent Reversible Lysine Acetylation of Cardiac Myosin Heavy Chain Isoforms Modulates Their Enzymatic and Motor Activity.

    PubMed

    Samant, Sadhana A; Pillai, Vinodkumar B; Sundaresan, Nagalingam R; Shroff, Sanjeev G; Gupta, Mahesh P

    2015-06-19

    Reversible lysine acetylation is a widespread post-translational modification controlling the activity of proteins in different subcellular compartments. We previously demonstrated that a class II histone deacetylase (HDAC), HDAC4, and a histone acetyltransferase, p300/CREB-binding protein-associated factor, associate with cardiac sarcomeres and that a class I and II HDAC inhibitor, trichostatin A, enhances contractile activity of myofilaments. In this study we show that a class I HDAC, HDAC3, is also present at cardiac sarcomeres. By immunohistochemical and electron microscopic analyses, we found that HDAC3 was localized to A-band of sarcomeres and capable of deacetylating myosin heavy chain (MHC) isoforms. The motor domains of both cardiac α- and β-MHC isoforms were found to be reversibly acetylated. Biomechanical studies revealed that lysine acetylation significantly decreased the Km for the actin-activated ATPase activity of MHC isoforms. By in vitro motility assay, we found that lysine acetylation increased the actin-sliding velocity of α-myosin by 20% and β-myosin by 36% compared with their respective non-acetylated isoforms. Moreover, myosin acetylation was found to be sensitive to cardiac stress. During induction of hypertrophy, myosin isoform acetylation increased progressively with duration of stress stimuli independently of isoform shift, suggesting that lysine acetylation of myosin could be an early response of myofilaments to increase contractile performance of the heart. These studies provide the first evidence for localization of HDAC3 at myofilaments and uncover a novel mechanism modulating the motor activity of cardiac MHC isoforms.

  20. Histone deacetylase inhibitor BML-210 induces growth inhibition and apoptosis and regulates HDAC and DAPC complex expression levels in cervical cancer cells.

    PubMed

    Borutinskaite, Veronika V; Magnusson, Karl-Eric; Navakauskiene, Ruta

    2012-12-01

    Histone deacetylase inhibitors (HDACIs) represent a new class of targeted anti-cancer agents and different other diseases, like muscular disorders. A number of studies have shown that extracellular signal-activated kinases can target chromatin-modifying complexes directly and regulate their function. The molecular connection between the dystrophin-associated protein complex (DAPC) and chromatin has been described, by showing that NO signaling regulates histone deacetylase (HDAC) activity and influences gene expression in different cell types. In present study, we investigated HDACs changes in HeLa cells undergoing growth inhibition and apoptosis, caused by HDACI BML-210 and retinoic acid (ATRA). Cell cycle analysis indicated that HeLa cell treatment with 20 and 30 μM concentration of BML-210 increased the proportion of cells in G0/G1 phase, and caused accumulation in subG1, indicating that the cells are undergoing apoptosis. We determined down-regulation of HDAC 1-5 and 7 after treatment with BML-210. Also, we demonstrated expression of different isoforms of alpha-dystrobrevin (α-DB) and other components of DAPC such as syntrophin, dystrophin, beta-dystrobrevin (β-DB) and NOS in HeLa cells after treatments. We determined changes in protein expression level of dystrophin, NOS1, α- and β-DB and in subcellular localization of α-DB after treatments with BML-210 and ATRA. In conclusion, these results suggest that HDACI BML-210 can inhibit cell growth and induce apoptosis in cervical cancer cells, what correlates with down-regulation of HDAC class I and II and changes in the DAPC expression levels. This can be important for identifying target proteins in DAPC signaling to HDACs, as a target of pharmacological intervention for treatment of muscular dystrophies and other diseases.

  1. Butyrate Histone Deacetylase Inhibitors

    PubMed Central

    Boosalis, Michael S.; Perrine, Susan P.; Sangerman, José

    2012-01-01

    Abstract In addition to being a part of the metabolic fatty acid fuel cycle, butyrate is also capable of inducing growth arrest in a variety of normal cell types and senescence-like phenotypes in gynecological cancer cells, inhibiting DNA synthesis and cell growth in colonic tumor cell lines, suppressing hTERT mRNA expression and telomerase activity in human prostate cancer cells, and inducing stem cell differentiation and apoptosis by DNA fragmentation. It regulates gene expression by inhibiting histone deacetylases (HDACs), enhances memory recovery and formation in mice, stimulates neurogenesis in the ischemic brain, promotes osteoblast formation, selectively blocks cell replication in transformed cells (compared to healthy cells), and can prevent and treat diet-induced obesity and insulin resistance in mouse models of obesity, as well as stimulate fetal hemoglobin expression in individuals with hematologic diseases such as the thalassemias and sickle-cell disease, in addition to a multitude of other biochemical effects in vivo. However, efforts to exploit the potential of butyrate in the clinical treatment of cancer and other medical disorders are thwarted by its poor pharmacological properties (short half-life and first-pass hepatic clearance) and the multigram doses needed to achieve therapeutic concentrations in vivo. Herein, we review some of the methods used to overcome these difficulties with an emphasis on HDAC inhibition. PMID:23514803

  2. Inhibition of Histone Deacetylases (HDACs) and mTOR Signaling: Novel Strategies Toward the Treatment of Prostate Cancer

    DTIC Science & Technology

    2011-04-01

    protein and vessel density in xenograft models with constitutive mTOR activity, either through loss of PTEN (PC3 cells) or VHL (C2 cells) [19]. Myc-CaP/AS...et al. (2006) Class II histone deacetylases are associated with VHL -independent regulation of hypoxia- inducible factor 1 alpha. Cancer Res 66: 8814

  3. Rho-kinase signaling controls nucleocytoplasmic shuttling of class IIa Histone Deacetylase (HDAC7) and transcriptional activation of orphan nuclear receptor NR4A1

    SciTech Connect

    Compagnucci, Claudia; Barresi, Sabina; Petrini, Stefania; Bertini, Enrico; Zanni, Ginevra

    2015-04-03

    Rho-kinase (ROCK) has been well documented to play a key role in RhoA-induced actin remodeling. ROCK activation results in myosin light chain (MLC) phosphorylation either by direct action on MLC kinase (MLCK) or by inhibition of MLC phosphatase (MLCP), modulating actin–myosin contraction. We found that inhibition of the ROCK pathway in induced pluripotent stem cells, leads to nuclear export of HDAC7 and transcriptional activation of the orphan nuclear receptor NR4A1 while in cells with constitutive ROCK hyperactivity due to loss of function of the RhoGTPase activating protein Oligophrenin-1 (OPHN1), the orphan nuclear receptor NR4A1 is downregulated. Our study identify a new target of ROCK signaling via myosin phosphatase subunit (MYPT1) and Histone Deacetylase (HDAC7) at the nuclear level and provide new insights in the cellular functions of ROCK. - Highlights: • ROCK regulates nucleocytoplasmic shuttling of HDAC7 via phosphorylation of MYPT1. • Nuclear export of HDAC7 and upregulation of NR4A1 occurs with low ROCK activity. • High levels of ROCK activity due to OPHN1 loss of function downregulate NR4A1.

  4. Profile of Class I Histone Deacetylases (HDAC) by Human Dendritic Cells after Alcohol Consumption and In Vitro Alcohol Treatment and Their Implication in Oxidative Stress: Role of HDAC Inhibitors Trichostatin A and Mocetinostat.

    PubMed

    Agudelo, Marisela; Figueroa, Gloria; Parira, Tiyash; Yndart, Adriana; Muñoz, Karla; Atluri, Venkata; Samikkannu, Thangavel; Nair, Madhavan P

    2016-01-01

    Epigenetic mechanisms have been shown to play a role in alcohol use disorders (AUDs) and may prove to be valuable therapeutic targets. However, the involvement of histone deacetylases (HDACs) on alcohol-induced oxidative stress of human primary monocyte-derived dendritic cells (MDDCs) has not been elucidated. In the current study, we took a novel approach combining ex vivo, in vitro and in silico analyses to elucidate the mechanisms of alcohol-induced oxidative stress and role of HDACs in the periphery. ex vivo and in vitro analyses of alcohol-modulation of class I HDACs and activity by MDDCs from self-reported alcohol users and non-alcohol users was performed. Additionally, MDDCs treated with alcohol were assessed using qRT-PCR, western blot, and fluorometric assay. The functional effects of alcohol-induce oxidative stress were measured in vitro using PCR array and in silico using gene expression network analysis. Our findings show, for the first time, that MDDCs from self-reported alcohol users have higher levels of class I HDACs compare to controls and alcohol treatment in vitro differentially modulates HDACs expression. Further, HDAC inhibitors (HDACi) blocked alcohol-induction of class I HDACs and modulated alcohol-induced oxidative stress related genes expressed by MDDCs. In silico analysis revealed new target genes and pathways on the mode of action of alcohol and HDACi. Findings elucidating the ability of alcohol to modulate class I HDACs may be useful for the treatment of alcohol-induced oxidative damage and may delineate new potential immune-modulatory mechanisms.

  5. Nonpeptide Macrocyclic Histone Deacetylase Inhibitors

    PubMed Central

    Oyelere, Adegboyega K.; Chen, Po C.; Guerrant, William; Mwakwari, Sandra C.; Hood, Rebecca; Zhang, Yunzhe; Fan, Yuhong

    2009-01-01

    Inhibition of Histone Deacetylases inhibitors (HDACi) hold great promise in cancer therapy due to their demonstrated ability to arrest proliferation of nearly all transformed cell types. Of the several structurally distinct small molecules HDACi reported, macrocyclic depsipeptides have the most complex recognition cap-group moieties and present an excellent opportunity for the modulation of the biological activities of HDACi. Unfortunately, the structure–activity relationship (SAR) studies for this class of compounds have been impaired largely because most macrocyclic HDACi known to date are comprised of complex peptide macrocycles. In addition to retaining the pharmacologically disadvantaged peptidyl-backbone, they offer only limited opportunity for side-chain modifications. Here we report the discovery of a new class of macrocyclic HDACi based on the macrolide antibiotics skeletons. SAR studies revealed that these compounds displayed both linker-length and macrolide-type dependent HDAC inhibition activities with IC50 in low nanomolar range. In addition, these nonpeptide macrocyclic HDACi are more selective against HDAC 1 and 2 relative to HDAC 8, another class I HDAC isoform, hence have sub-class HDAC isoform selectivity. PMID:19093884

  6. The potential of histone deacetylase inhibitors in lung cancer.

    PubMed

    Aparicio, Ana

    2006-03-01

    In the nucleus, DNA is wrapped around octamers of histone proteins. Histones, like other proteins, are posttranslationally modified by the addition of an array of chemical groups that affect their interactions with surrounding structures. Histone acetyltransferases and histone deacetylases (HDACs) are the enzymes involved in the addition and removal, respectively, of acetyl groups from the aminoterminal tails of histones. A number of structurally diverse compounds are capable of inhibiting HDACs and exert a variety of biologic effects on cancer cells in preclinical models. Early clinical trials with the first generation of HDAC inhibitors (HDACIs) have demonstrated promising therapeutic activity, and HDACs have become one of the hottest targets in drug development today.

  7. Histone deacetylases in kidney development: implications for disease and therapy.

    PubMed

    Chen, Shaowei; El-Dahr, Samir S

    2013-05-01

    Histone deacetylases (HDACs) are an evolutionarily conserved group of enzymes that regulate a broad range of biological processes through removal of acetyl groups from histones as well as non-histone proteins. Recent studies using a variety of pharmacological inhibitors and genetic models of HDACs have revealed a central role of HDACs in control of kidney development. These findings provide new insights into the epigenetic mechanisms underlying congenital anomalies of the kidney and urinary tract (CAKUT) and implicate the potential of HDACs as therapeutic targets in kidney diseases, such as cystic kidney diseases and renal cell cancers. Determining the specific functions of individual HDAC members would be an important task of future research.

  8. Histone deacetylases: unique players in shaping the epigenetic histone code.

    PubMed

    Thiagalingam, Sam; Cheng, Kuang-Hung; Lee, Hyunjoo J; Mineva, Nora; Thiagalingam, Arunthathi; Ponte, Jose F

    2003-03-01

    The epigenome is defined by DNA methylation patterns and the associated posttranslational modifications of histones. This histone code determines the expression status of individual genes dependent upon their localization on the chromatin. The silencing of gene expression is associated with deacetylated histones, which are often found to be associated with regions of DNA methylation as well as methylation at the lysine 4 residue of histone 3. In contrast, the activation of gene expression is associated with acetylated histones and methylation at the lysine 9 residue of histone 3. The histone deactylases play a major role in keeping the balance between the acetylated and deacetylated states of chromatin. Histone deacetylases (HDACs) are divided into three classes: class I HDACs (HDACs 1, 2, 3, and 8) are similar to the yeast RPD3 protein and localize to the nucleus; class II HDACs (HDACs 4, 5, 6, 7, 9, and 10) are homologous to the yeast HDA1 protein and are found in both the nucleus and cytoplasm; and class III HDACs form a structurally distinct class of NAD-dependent enzymes that are similar to the yeast SIR2 proteins. Since inappropriate silencing of critical genes can result in one or both hits of tumor suppressor gene (TSG) inactivation in cancer, theoretically the reactivation of affected TSGs could have an enormous therapeutic value in preventing and treating cancer. Indeed, several HDAC inhibitors are currently being developed and tested for their potency in cancer chemotherapy. Importantly, these agents are also potentially applicable to chemoprevention if their toxicity can be minimized. Despite the toxic side effects and lack of specificity of some of the inhibitors, progress is being made. With the elucidation of the structures, functions and modes of action of HDACs, finding agents that may be targeted to specific HDACs and potentially reactivate expression of only a defined set of affected genes in cancer will be more attainable.

  9. Chemical origins of isoform selectivity in histone deacetylase inhibitors.

    PubMed

    Butler, Kyle V; Kozikowski, Alan P

    2008-01-01

    Histones undergo extensive posttranslational modifications that affect gene expression. Acetylation is a key histone modification that is primarily regulated by two enzymes, one of which is histone deacetylase (HDAC). The activity of HDAC causes transcriptional silencing of DNA. Eleven distinct zinc-dependent histone deacetylase isoforms have been identified in humans. Each isoform has a unique structure and function, and regulates a unique set of genes. HDAC is responsible for the regulation of many genes involved in cancer cell proliferation, and it has been implicated in the pathogenesis of many neurological conditions. HDAC inhibitors are known to be very effective anti-cancer agents, and research has shown them to be potential treatments for many other conditions. Histone deacetylase inhibitors modify the expression of many genes, and it is possible that inhibition of one isoform could cause epigenetic changes that are beneficial to treatment of a disease, while inhibition of another isoform could cause contradictory changes. Selective HDAC inhibitors will be better able to avoid these types of situations than non-specific inhibitors, and may also be less toxic than pan-HDAC inhibitors. Many potent pan-HDAC inhibitors have already been developed, leaving the development of selective inhibitors at the forefront of HDAC drug development. Certain structural moieties may be added to HDAC inhibitors to give isoform selectivity, and these will be discussed in this review. This review will focus on the applications of selective HDAC inhibitors, inhibitors reported to show selectivity, and the relationship between inhibitor structure and selectivity.

  10. Histone deacetylase inhibitors (HDACIs): multitargeted anticancer agents

    PubMed Central

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

    2013-01-01

    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

  11. Transcriptional Regulation of JARID1B/KDM5B Histone Demethylase by Ikaros, Histone Deacetylase 1 (HDAC1), and Casein Kinase 2 (CK2) in B-cell Acute Lymphoblastic Leukemia.

    PubMed

    Wang, Haijun; Song, Chunhua; Ding, Yali; Pan, Xiaokang; Ge, Zheng; Tan, Bi-Hua; Gowda, Chandrika; Sachdev, Mansi; Muthusami, Sunil; Ouyang, Hongsheng; Lai, Liangxue; Francis, Olivia L; Morris, Christopher L; Abdel-Azim, Hisham; Dorsam, Glenn; Xiang, Meixian; Payne, Kimberly J; Dovat, Sinisa

    2016-02-19

    Impaired function of the Ikaros (IKZF1) protein is associated with the development of high-risk B-cell precursor acute lymphoblastic leukemia (B-ALL). The mechanisms of Ikaros tumor suppressor activity in leukemia are unknown. Ikaros binds to the upstream regulatory elements of its target genes and regulates their transcription via chromatin remodeling. Here, we report that Ikaros represses transcription of the histone H3K4 demethylase, JARID1B (KDM5B). Transcriptional repression of JARID1B is associated with increased global levels of H3K4 trimethylation. Ikaros-mediated repression of JARID1B is dependent on the activity of the histone deacetylase, HDAC1, which binds to the upstream regulatory element of JARID1B in complex with Ikaros. In leukemia, JARID1B is overexpressed, and its inhibition results in cellular growth arrest. Ikaros-mediated repression of JARID1B in leukemia is impaired by pro-oncogenic casein kinase 2 (CK2). Inhibition of CK2 results in increased binding of the Ikaros-HDAC1 complex to the promoter of JARID1B, with increased formation of trimethylated histone H3 lysine 27 and decreased histone H3 Lys-9 acetylation. In cases of high-risk B-ALL that carry deletion of one Ikaros (IKZF1) allele, targeted inhibition of CK2 restores Ikaros binding to the JARID1B promoter and repression of JARID1B. In summary, the presented data suggest a mechanism through which Ikaros and HDAC1 regulate the epigenetic signature in leukemia: via regulation of JARID1B transcription. The presented data identify JARID1B as a novel therapeutic target in B-ALL and provide a rationale for the use of CK2 inhibitors in the treatment of high-risk B-ALL.

  12. Transcriptional Regulation of JARID1B/KDM5B Histone Demethylase by Ikaros, Histone Deacetylase 1 (HDAC1), and Casein Kinase 2 (CK2) in B-cell Acute Lymphoblastic Leukemia*

    PubMed Central

    Wang, Haijun; Song, Chunhua; Ding, Yali; Pan, Xiaokang; Ge, Zheng; Tan, Bi-Hua; Gowda, Chandrika; Sachdev, Mansi; Muthusami, Sunil; Ouyang, Hongsheng; Lai, Liangxue; Francis, Olivia L.; Morris, Christopher L.; Abdel-Azim, Hisham; Dorsam, Glenn; Xiang, Meixian; Payne, Kimberly J.; Dovat, Sinisa

    2016-01-01

    Impaired function of the Ikaros (IKZF1) protein is associated with the development of high-risk B-cell precursor acute lymphoblastic leukemia (B-ALL). The mechanisms of Ikaros tumor suppressor activity in leukemia are unknown. Ikaros binds to the upstream regulatory elements of its target genes and regulates their transcription via chromatin remodeling. Here, we report that Ikaros represses transcription of the histone H3K4 demethylase, JARID1B (KDM5B). Transcriptional repression of JARID1B is associated with increased global levels of H3K4 trimethylation. Ikaros-mediated repression of JARID1B is dependent on the activity of the histone deacetylase, HDAC1, which binds to the upstream regulatory element of JARID1B in complex with Ikaros. In leukemia, JARID1B is overexpressed, and its inhibition results in cellular growth arrest. Ikaros-mediated repression of JARID1B in leukemia is impaired by pro-oncogenic casein kinase 2 (CK2). Inhibition of CK2 results in increased binding of the Ikaros-HDAC1 complex to the promoter of JARID1B, with increased formation of trimethylated histone H3 lysine 27 and decreased histone H3 Lys-9 acetylation. In cases of high-risk B-ALL that carry deletion of one Ikaros (IKZF1) allele, targeted inhibition of CK2 restores Ikaros binding to the JARID1B promoter and repression of JARID1B. In summary, the presented data suggest a mechanism through which Ikaros and HDAC1 regulate the epigenetic signature in leukemia: via regulation of JARID1B transcription. The presented data identify JARID1B as a novel therapeutic target in B-ALL and provide a rationale for the use of CK2 inhibitors in the treatment of high-risk B-ALL. PMID:26655717

  13. Tau--an inhibitor of deacetylase HDAC6 function.

    PubMed

    Perez, Mar; Santa-Maria, Ismael; Gomez de Barreda, Elena; Zhu, Xiongwei; Cuadros, Raquel; Cabrero, Jose Roman; Sanchez-Madrid, Francisco; Dawson, Hana N; Vitek, Michael P; Perry, George; Smith, Mark A; Avila, Jesus

    2009-06-01

    Analysis of brain microtubule protein from patients with Alzheimer's disease showed decreased alpha tubulin levels along with increased acetylation of the alpha tubulin subunit, mainly in those microtubules from neurons containing neurofibrillary tau pathology. To determine the relationship of tau protein and increased tubulin acetylation, we studied the effect of tau on the acetylation-deacetylation of tubulin. Our results indicate that tau binds to the tubulin-deacetylase, histone deacetylase 6 (HDAC6), decreasing its activity with a consequent increase in tubulin acetylation. As expected, increased acetylation was also found in tubulin from wild-type mice compared with tubulin from mice lacking tau because of the tau-mediated inhibition of the deacetylase. In addition, we found that an excess of tau protein, as a HDAC6 inhibitor, prevents induction of autophagy by inhibiting proteasome function.

  14. Histone deacetylases 9 and 10 are required for homologous recombination.

    PubMed

    Kotian, Shweta; Liyanarachchi, Sandhya; Zelent, Arthur; Parvin, Jeffrey D

    2011-03-11

    We tested the role of histone deacetylases (HDACs) in the homologous recombination process. A tissue-culture based homology-directed repair assay was used in which repair of a double-stranded break by homologous recombination results in gene conversion of an inactive GFP allele to an active GFP gene. Our rationale was that hyperacetylation caused by HDAC inhibitor treatment would increase chromatin accessibility to repair factors, thereby increasing homologous recombination. Contrary to expectation, treatment of cells with the inhibitors significantly reduced homologous recombination activity. Using RNA interference to deplete each HDAC, we found that depletion of either HDAC9 or HDAC10 specifically inhibited homologous recombination. By assaying for sensitivity of cells to the interstrand cross-linker mitomycin C, we found that treatment of cells with HDAC inhibitors or depletion of HDAC9 or HDAC10 resulted in increased sensitivity to mitomycin C. Our data reveal an unanticipated function of HDAC9 and HDAC10 in the homologous recombination process.

  15. Cathepsin H-Mediated Degradation of HDAC4 for Matrix Metalloproteinase Expression in Hepatic Stellate Cells: Implications of Epigenetic Suppression of Matrix Metalloproteinases in Fibrosis through Stabilization of Class IIa Histone Deacetylases.

    PubMed

    Yang, Zemin; Liu, Yu; Qin, Lan; Wu, Pengfei; Xia, Zanxian; Luo, Mei; Zeng, Yilan; Tsukamoto, Hidekazu; Ju, Zongyun; Su, Danmei; Kang, Han; Xiao, Zhixiong; Zheng, Sujun; Duan, Zhongping; Hu, Richard; Wang, Qiang; Pandol, Stephen J; Han, Yuan-Ping

    2017-02-01

    In three-dimensional extracellular matrix, mesenchymal cells including hepatic stellate cells (HSCs) gain the ability to express matrix metalloproteinases (MMPs) on injury signals. In contrast, in myofibroblastic HSCs in fibrotic liver, many MMP genes are silenced into an epigenetically nonpermissive state. The mechanism by which the three-dimensional extracellular matrix confers the MMP genes into an epigenetically permissive state has not been well characterized. In continuation of previous work, we show here that the up-regulation of MMP genes is mediated through degradation of class IIa histone deacetylases (HDACs) by certain cysteine cathepsins (Cts). In three-dimensional extracellular matrix culture, CtsH, among other cysteine cathepsins, was up-regulated and localized as puncta in the nuclear and cytoplasmic compartments in a complex with HDAC4 for its degradation. Conversely, along with HSC trans-differentiation, CtsH and CtsL were progressively down-regulated, whereas HDAC4 was concurrently stabilized. The inhibition of cysteine cathepsins by specific proteinase inhibitors or chloroquine, which raises cellular pH, restored HDAC4. Recombinant CtsH could break down HDAC4 in the transfected cells and in vitro at acidic pH. In human cirrhotic liver, activated HSCs express high levels of class IIa HDACs but little CtsH. We propose that cysteine cathepsin-mediated degradation of class IIa HDACs plays a key role in the modulation of MMP expression/suppression and HSC functions in tissue injury and fibrosis.

  16. Discovery, synthesis, and pharmacological evaluation of spiropiperidine hydroxamic acid based derivatives as structurally novel histone deacetylase (HDAC) inhibitors.

    PubMed

    Varasi, Mario; Thaler, Florian; Abate, Agnese; Bigogno, Chiara; Boggio, Roberto; Carenzi, Giacomo; Cataudella, Tiziana; Dal Zuffo, Roberto; Fulco, Maria Carmela; Rozio, Marco Giulio; Mai, Antonello; Dondio, Giulio; Minucci, Saverio; Mercurio, Ciro

    2011-04-28

    New spiro[chromane-2,4'-piperidine] and spiro[benzofuran-2,4'-piperidine] hydroxamic acid derivatives as HDAC inhibitors have been identified by combining privileged structures with a hydroxamic acid moiety as zinc binding group. The compounds were evaluated for their ability to inhibit nuclear extract HDACs and for their in vitro antiproliferative activity on different tumor cell lines. This work resulted in the discovery of spirocycle 30d that shows good oral bioavailability and tumor growth inhibition in an HCT-116 murine xenograft model.

  17. Design and synthesis of a potent histone deacetylase inhibitor.

    PubMed

    Liu, Tao; Kapustin, Galina; Etzkorn, Felicia A

    2007-05-03

    Histone deacetylase (HDAC) inhibitors have potential for cancer therapy. An HDAC inhibitor based on a cyclic peptide mimic of known structure, linked by an aliphatic chain to a hydroxamic acid, was designed and synthesized. The chimeric compound showed potent competitive inhibition of nuclear HDACs, with an IC50 value of 46 nM and a Ki value of 13.7 nM. The designed inhibitor showed 4-fold selectivity for HDAC1 (57 nM) over HDAC8 (231 nM).

  18. Inhibition of Histone Deacetylases (HDACs) and mTOR Signaling: Novel Strategies Towards the Treatment of Prostate Cancer

    DTIC Science & Technology

    2012-04-01

    of the combination of the HDAC inhibitor panobinostat with the mTORC1 inhibitor everolimus . Panobinostat/ everolimus combination treatment resulted in...to single treatments. We identified that panobinostat/ everolimus combination resulted in enhanced anti-tumor activity mediated by decreased tumor...that low dose concurrent panobinostat/ everolimus combination therapy is well tolerated and results in greater anti-tumor activity and therapeutic

  19. Post-Training Intrahippocampal Inhibition of Class I Histone Deacetylases Enhances Long-Term Object-Location Memory

    ERIC Educational Resources Information Center

    Hawk, Joshua D.; Florian, Cedrick; Abel, Ted

    2011-01-01

    Long-term memory formation involves covalent modification of the histone proteins that package DNA. Reducing histone acetylation by mutating histone acetyltransferases impairs long-term memory, and enhancing histone acetylation by inhibiting histone deacetylases (HDACs) improves long-term memory. Previous studies using HDAC inhibitors to enhance…

  20. Suppression of caspase-11 expression by histone deacetylase inhibitors

    SciTech Connect

    Heo, Hyejung; Yoo, Lang; Shin, Ki Soon; Kang, Shin Jung

    2009-01-02

    It has been well documented that histone deacetylase inhibitors suppress inflammatory gene expression. Therefore, we investigated whether histone deacetylase inhibitors modulate the expression of caspase-11 that is known as an inducible caspase regulating both inflammation and apoptosis. In the present study, we show that sodium butyrate and trichostatin A, two structurally unrelated inhibitors of histone deacetylase (HDAC), effectively suppressed the induction of caspase-11 in mouse embryonic fibroblasts stimulated with lipopolysaccharides. Sodium butyrate inhibited the activation of upstream signaling events for the caspase-11 induction such as activation of p38 mitogen-activated protein kinase and c-Jun N-terminal kinase, degradation of inhibitor of {kappa}B, and activation of nuclear factor-{kappa}B. These results suggest that the HDAC inhibitor suppressed cytosolic signaling events for the induction of caspase-11 by inhibiting the deacetylation of non-histone proteins.

  1. Inhibitors of Histone Deacetylases Attenuate Noise-Induced Hearing Loss.

    PubMed

    Chen, Jun; Hill, Kayla; Sha, Su-Hua

    2016-08-01

    Loss of auditory sensory hair cells is the major pathological feature of noise-induced hearing loss (NIHL). Currently, no established clinical therapies for prevention or amelioration of NIHL are available. The absence of treatments is due to our lack of a comprehensive understanding of the molecular mechanisms underlying noise-induced damage. Our previous study indicates that epigenetic modification of histones alters hair cell survival. In this study, we investigated the effect of noise exposure on histone H3 lysine 9 acetylation (H3K9ac) in the inner ear of adult CBA/J mice and determined if inhibition of histone deacetylases by systemic administration of suberoylanilide hydroxamic acid (SAHA) could attenuate NIHL. Our results showed that H3K9ac was decreased in the nuclei of outer hair cells (OHCs) and marginal cells of the stria vascularis in the basal region after exposure to a traumatic noise paradigm known to induce permanent threshold shifts (PTS). Consistent with these results, levels of histone deacetylases 1, 2, and 3 (HDAC1, HDAC2 and HDAC3) were increased predominately in the nuclei of cochlear cells. Silencing of HDAC1, HDAC2, or HDAC3 with siRNA reduced the expression of the target HDAC in OHCs, but did not attenuate noise-induced PTS, whereas treatment with the pan-HDAC inhibitor SAHA, also named vorinostat, reduced OHC loss, and attenuated PTS. These findings suggest that histone acetylation is involved in the pathogenesis of noise-induced OHC death and hearing loss. Pharmacological targeting of histone deacetylases may afford a strategy for protection against NIHL.

  2. Novel Histone Deacetylase Inhibitors

    DTIC Science & Technology

    2003-07-01

    inhibit HDAC, promote differentiation and cell death in tissue culture lines of human breast cancer. Antimalarials, chloroquine and quinidine promote...breast tumor cell differentiation and cell death . A novel mechanism, regulation of HDAC1 by stimulating ubiguitination and proteasomal degradation of

  3. Histone deacetylase 9 is a negative regulator of adipogenic differentiation.

    PubMed

    Chatterjee, Tapan K; Idelman, Gila; Blanco, Victor; Blomkalns, Andra L; Piegore, Mark G; Weintraub, Daniel S; Kumar, Santosh; Rajsheker, Srinivas; Manka, David; Rudich, Steven M; Tang, Yaoliang; Hui, David Y; Bassel-Duby, Rhonda; Olson, Eric N; Lingrel, Jerry B; Ho, Shuk-Mei; Weintraub, Neal L

    2011-08-05

    Differentiation of preadipocytes into mature adipocytes capable of efficiently storing lipids is an important regulatory mechanism in obesity. Here, we examined the involvement of histone deacetylases (HDACs) and histone acetyltransferases (HATs) in the regulation of adipogenesis. We find that among the various members of the HDAC and HAT families, only HDAC9 exhibited dramatic down-regulation preceding adipogenic differentiation. Preadipocytes from HDAC9 gene knock-out mice exhibited accelerated adipogenic differentiation, whereas HDAC9 overexpression in 3T3-L1 preadipocytes suppressed adipogenic differentiation, demonstrating its direct role as a negative regulator of adipogenesis. HDAC9 expression was higher in visceral as compared with subcutaneous preadipocytes, negatively correlating with their potential to undergo adipogenic differentiation in vitro. HDAC9 localized in the nucleus, and its negative regulation of adipogenesis segregates with the N-terminal nuclear targeting domain, whereas the C-terminal deacetylase domain is dispensable for this function. HDAC9 co-precipitates with USF1 and is recruited with USF1 at the E-box region of the C/EBPα gene promoter in preadipocytes. Upon induction of adipogenic differentiation, HDAC9 is down-regulated, leading to its dissociation from the USF1 complex, whereas p300 HAT is up-regulated to allow its association with USF1 and accumulation at the E-box site of the C/EBPα promoter in differentiated adipocytes. This reciprocal regulation of HDAC9 and p300 HAT in the USF1 complex is associated with increased C/EBPα expression, a master regulator of adipogenic differentiation. These findings provide new insights into mechanisms of adipogenic differentiation and document a critical regulatory role for HDAC9 in adipogenic differentiation through a deacetylase-independent mechanism.

  4. Caspase-mediated specific cleavage of human histone deacetylase 4.

    PubMed

    Liu, Fang; Dowling, Melissa; Yang, Xiang-Jiao; Kao, Gary D

    2004-08-13

    Histone deacetylase 4 (HDAC4) is a class II HDAC implicated in controlling gene expression important for diverse cellular functions, but little is known about how its expression and stability are regulated. We report here that this deacetylase is unusually unstable, with a half-life of less than 8 h. Consistent with the instability of HDAC4 protein, its mRNA was also highly unstable (with a half-life of less than 4 h). The degradation of HDAC4 could be accelerated by exposure of cells to ultraviolet irradiation. HDAC4 degradation was not dependent on proteasome or CRM1-mediated export activity but instead was caspase-dependent and was detectable in diverse human cancer lines. Of two potential caspase consensus motifs in HDAC4, both lying within a region containing proline-, glutamic acid-, serine-, and threonine-rich (PEST) sequences, we identified, by site-directed mutagenesis, Asp-289 as the prime cleavage site. Notably, this residue is not conserved among other class IIa members, HDAC5, -7, and -9. Finally, the induced expression of caspase-cleavable HDAC4 led to markedly increased apoptosis. These results therefore unexpectedly link the regulation of HDAC4 protein stability to caspases, enzymes that are important for controlling cell death and differentiation.

  5. Phosphorus-based SAHA analogues as histone deacetylase inhibitors.

    PubMed

    Kapustin, Galina V; Fejér, György; Gronlund, Jennifer L; McCafferty, Dewey G; Seto, Edward; Etzkorn, Felicia A

    2003-08-21

    [structure: see text] Three analogues of suberoyl anilide hydroxamic acid (SAHA) with phosphorus metal-chelating functionalities were synthesized as inhibitors of histone deacetylases (HDACs). The compounds showed weak activity for HeLa nuclear extracts (IC(50) = 0.57-6.1 mM), HDAC8 (IC(50) = 0.28-0.41 mM), and histone-deacetylase-like protein (HDLP, IC(50) = 0.33-1.9 mM), suggesting that the transition state of HDAC is not analogous to zinc proteases. Antiproliferative activity against A2780 cancer cells (IC(50) = 0.11-0.12 mM), comparable to SAHA (0.15 mM), was observed.

  6. Histone deacetylases: salesmen and customers in the post-translational modification market.

    PubMed

    Brandl, André; Heinzel, Thorsten; Krämer, Oliver H

    2009-04-01

    HDACs (histone deacetylases) are enzymes that remove the acetyl moiety from N-epsilon-acetylated lysine residues in histones and non-histone proteins. In recent years, it has turned out that HDACs themselves are also subject to post-translational modification. Such structural alterations can determine the stability, localization, activity and protein-protein interactions of HDACs. This subsequently affects the modification of their substrates and the co-ordination of cellular signalling networks. Intriguingly, physiologically relevant non-histone proteins are increasingly found to be deacetylated by HDACs, and aberrant deacetylase activity contributes to several severe human diseases. Targeting the catalytic activity of these enzymes and their post-translational modifications are therefore attractive targets for therapeutical intervention strategies. To achieve this ambitious goal, details on the molecular mechanisms regulating post-translational modifications of HDACs are required. This review summarizes aspects of the current knowledge on the biological role and enzymology of the phosphorylation, acetylation, ubiquitylation and sumoylation of HDACs.

  7. Inhibition of histone deacetylase as a new mechanism of teratogenesis.

    PubMed

    Menegola, Elena; Di Renzo, Francesca; Broccia, Maria Luisa; Giavini, Erminio

    2006-12-01

    Histone deacetylases (HDACs) are nuclear and cytoplasmic enzymes that deacetylate a number of substrates, of which histones are the best known and described in the literature. HDACs are present in eukaryotic and bacteria cells, and are fundamental for a number of cellular functions, including correct gene expression. Surprisingly, only up to 20% of the whole genome is controlled by HDACs, but key processes for survival, proliferation, and differentiation have been strictly linked to HDAC enzyme functioning. The use of HDAC inhibitors (HDACi) has been proposed for the treatment of neoplastic diseases. Their effectiveness has been suggested for a number of liquid and solid tumors, particularly acute promyelocytic leukemia (APL). The role of HDACs in embryo development is currently under investigation. Published data indicate knockout phenotype analysis to be of particular interest, in which a number of HDACs play a key role during development. Little data have been published on the effects of HDACi on embryonic development, although for valproic acid (VPA), literature from the 1980s described its teratogenic effects in experimental animals and humans. To date, all tested HDACi have shown teratogenic effects similar to those described for VPA when tested in zebrafish, Xenopus laevis, and mice. HDACs were also able to alter embryo development in invertebrates and plants. A model, similar to that proposed in APL, involving retinoic acid receptors (RAR) and tissue specific Hox gene expression, is suggested to explain the HDAC effects on embryo development.

  8. Histone Deacetylase Inhibitors Preserve Function in Aging Axons

    PubMed Central

    Baltan, Selva

    2012-01-01

    Aging increases the vulnerability of aging white matter to ischemic injury. Histone deacetylase (HDAC) inhibitors preserve young adult white matter structure and function during ischemia by conserving ATP and reducing excitotoxicity. In isolated optic nerve from 12 month old mice, deprived of oxygen and glucose, we show that pan- and Class I specific HDAC inhibitors promote functional recovery of axons. This protection correlates with preservation of axonal mitochondria. The cellular expression of HDAC 3, in the central nervous system (CNS) and HDAC 2 in optic nerve considerably changed with age expanding to more cytoplasmic domains from nuclear compartments suggesting that changes in glial cell protein acetylation may confer protection to aging axons. Our results indicate manipulation of HDAC activities in glial cells may have a universal potential for stroke therapy across age groups. PMID:23050648

  9. SQSTM1/p62 interacts with HDAC6 and regulates deacetylase activity.

    PubMed

    Yan, Jin; Seibenhener, Michael Lamar; Calderilla-Barbosa, Luis; Diaz-Meco, Maria-Theresa; Moscat, Jorge; Jiang, Jianxiong; Wooten, Marie W; Wooten, Michael C

    2013-01-01

    Protein aggregates can form in the cytoplasm of the cell and are accumulated at aggresomes localized to the microtubule organizing center (MTOC) where they are subsequently degraded by autophagy. In this process, aggregates are engulfed into autophagosomes which subsequently fuse with lysosomes for protein degradation. A member of the class II histone deacetylase family, histone deacetylase 6(HDAC6) has been shown to be involved in both aggresome formation and the fusion of autophagosomes with lysosomes making it an attractive target to regulate protein aggregation. The scaffolding protein sequestosome 1(SQSTM1)/p62 has also been shown to regulate accumulation and autophagic clearance of protein aggregates. Recent studies have revealed colocalization of HDAC6 and p62 to ubiquitinated mitochondria, as well as, ubiquitinated protein aggregates associated with the E3 ubiquitin ligase TRIM50. HDAC6 deacetylase activity is required for aggresome formation and can be regulated by protein interaction with HDAC6. Due to their colocalization at ubiquitinated protein aggregates, we sought to examine if p62 specifically interacted with HDAC6 and if so, if this interaction had any effect on HDAC6 activity and/or the physiological function of cortactin-F-actin assembly. We succeeded in identifying and mapping the direct interaction between HDAC6 and p62. We further show that this interaction regulates HDAC6 deacetylase activity. Data are presented demonstrating that the absence of p62 results in hyperactivation of HDAC6 and deacetylation of α-tubulin and cortactin. Further, upon induction of protein misfolding we show that p62 is required for perinuclear co-localization of cortactin-F-actin assemblies. Thus, our findings indicate that p62 plays a key role in regulating the recruitment of F-actin network assemblies to the MTOC, a critical cellular function that is required for successful autophagic clearance of protein aggregates.

  10. Targeting Histone Deacetylases in Diseases: Where Are We?

    PubMed Central

    Benedetti, Rosaria; Conte, Mariarosaria

    2015-01-01

    Abstract Significance: Epigenetic inactivation of pivotal genes involved in cell growth is a hallmark of human pathologies, in particular cancer. Histone acetylation balance obtained through opposing actions of histone deacetylases (HDACs) and histone acetyltransferases is one epigenetic mechanism controlling gene expression and is, thus, associated with disease etiology and progression. Interfering pharmacologically with HDAC activity can correct abnormalities in cell proliferation, migration, vascularization, and death. Recent Advances: Histone deacetylase inhibitors (HDACi) represent a new class of cytostatic agents that interfere with the function of HDACs and are able to increase gene expression by indirectly inducing histone acetylation. Several HDACi, alone or in combination with DNA-demethylating agents, chemopreventive, or classical chemotherapeutic drugs, are currently being used in clinical trials for solid and hematological malignancies, and are, thus, promising candidates for cancer therapy. Critical Issues: (i) Non-specific (off-target) HDACi effects due to activities unassociated with HDAC inhibition. (ii) Advantages/disadvantages of non-selective or isoform-directed HDACi. (iii) Limited number of response-predictive biomarkers. (iv) Toxicity leading to dysfunction of critical biological processes. Future Directions: Selective HDACi could achieve enhanced clinical utility by reducing or eliminating the serious side effects associated with current first-generation non-selective HDACi. Isoform-selective and pan-HDACi candidates might benefit from the identification of biomarkers, enabling better patient stratification and prediction of response to treatment. Antioxid. Redox Signal. 23, 99–126. PMID:24382114

  11. Treatment of chronic kidney diseases with histone deacetylase inhibitors

    PubMed Central

    Liu, Na; Zhuang, Shougang

    2015-01-01

    Histone deacetylases (HDACs) induce deacetylation of both histone and non-histone proteins and play a critical role in the modulation of physiological and pathological gene expression. Pharmacological inhibition of HDAC has been reported to attenuate progression of renal fibrogenesis in obstructed kidney and reduce cyst formation in polycystic kidney disease. HDAC inhibitors (HDACis) are also able to ameliorate renal lesions in diabetes nephropathy, lupus nephritis, aristolochic acid nephropathy, and transplant nephropathy. The beneficial effects of HDACis are associated with their anti-fibrosis, anti-inflammation, and immunosuppressant effects. In this review, we summarize recent advances on the treatment of various chronic kidney diseases with HDACis in pre-clinical models. PMID:25972812

  12. Protein kinase CK2-mediated phosphorylation of HDAC2 regulates co-repressor formation, deacetylase activity and acetylation of HDAC2 by cigarette smoke and aldehydes.

    PubMed

    Adenuga, David; Rahman, Irfan

    2010-06-01

    Histone deacetylase 2 (HDAC2) mediates the repression of pro-inflammatory genes by deacetylating core histones, RelA/p65 and the glucocorticoid receptor. Reduced level of HDAC2 is associated with steroid resistant inflammation caused by cigarette smoke (CS)-derived oxidants and aldehydes. However, the molecular mechanisms regulating HDAC2 in response to CS and aldehydes is not known. Here, we report that CS extract, and aldehyde acrolein induced phosphorylation of HDAC2 which was abolished by mutations at serine sites S(394), S(411), S(422) and S(424). HDAC2 phosphorylation required direct interaction with serine-phosphorylated protein kinase CK2alpha and involved reduced HDAC2 deacetylase activity. Furthermore, HDAC2 phosphorylation was required for HDAC2 interaction with transcription factors, co-repressor complex formation, CBP recruitment, acetylation on lysine residues and modulates transrepression activity. Thus, phospho-acetylation of HDAC2 negatively regulates its deacetylase activity which has implications in steroid resistance in chronic inflammatory conditions.

  13. Class IIa Histone Deacetylases Are Conserved Regulators of Circadian Function*

    PubMed Central

    Fogg, Paul C. M.; O'Neill, John S.; Dobrzycki, Tomasz; Calvert, Shaun; Lord, Emma C.; McIntosh, Rebecca L. L.; Elliott, Christopher J. H.; Sweeney, Sean T.; Hastings, Michael H.; Chawla, Sangeeta

    2014-01-01

    Class IIa histone deacetylases (HDACs) regulate the activity of many transcription factors to influence liver gluconeogenesis and the development of specialized cells, including muscle, neurons, and lymphocytes. Here, we describe a conserved role for class IIa HDACs in sustaining robust circadian behavioral rhythms in Drosophila and cellular rhythms in mammalian cells. In mouse fibroblasts, overexpression of HDAC5 severely disrupts transcriptional rhythms of core clock genes. HDAC5 overexpression decreases BMAL1 acetylation on Lys-537 and pharmacological inhibition of class IIa HDACs increases BMAL1 acetylation. Furthermore, we observe cyclical nucleocytoplasmic shuttling of HDAC5 in mouse fibroblasts that is characteristically circadian. Mutation of the Drosophila homolog HDAC4 impairs locomotor activity rhythms of flies and decreases period mRNA levels. RNAi-mediated knockdown of HDAC4 in Drosophila clock cells also dampens circadian function. Given that the localization of class IIa HDACs is signal-regulated and influenced by Ca2+ and cAMP signals, our findings offer a mechanism by which extracellular stimuli that generate these signals can feed into the molecular clock machinery. PMID:25271152

  14. A positive regulatory domain in CCAAT/enhancer binding protein β (C/EBPΒ) is required for the glucocorticoid-mediated displacement of histone deacetylase 1 (HDAC1) from the C/ebpα promoter and maximum adipogenesis.

    PubMed

    Abdou, Houssein-Salem; Atlas, Ella; Haché, Robert J G

    2013-04-01

    Glucocorticoids promote adipogenesis and contribute to the metabolic syndrome through a number of mechanisms. One of the effectors of glucocorticoid action is the CCAAT/enhancer binding protein β (C/EBPβ). C/EBPβ is a basic leucine-zipper transcription factor involved in diverse processes including differentiation, cellular proliferation, and inflammation. C/EBPβ transcriptional activity is regulated, in part, by its acetylation profile resulting from its dynamic interaction with either acetylases general control nonrepressed protein 5/p300/CBP associated factor (GCN5/PCAF) or deacetylase complexes (mSin3A/histone deacetylase 1 [HDAC1]). Glucocorticoid treatment of preadipocytes promotes C/EBPβ acetylation, leading to mSin3A/HDAC1 dissociation from C/EBPβ and resulting in C/ebpα promoter activation at the onset of adipogenesis, thus increasing the differentiation rate. We recently showed that the regulatory domain 1 (RD1) of C/EBPβ contains four residues (153-156) required for its interaction with HDAC1, therefore supporting RD1 proposed inhibitory role. In an attempt to further elucidate the intrinsic regulatory property of RD1, we sought to characterize the regulatory potential of the N terminus region of RD1 (residues 141-149). In this study, we show that C/EBPβΔ141-149 transcriptional activity was compromised on the C/ebpα, but not on the Pparγ, promoter. Additionally, the ability of C/EBPβΔ141-149 to induce adipogenesis in NIH 3T3 cells was compromised when compared with C/EBPβwt owing to a delayed expression of C/ebpα at the onset of differentiation. Furthermore, the data suggest that the reduced expression of C/ebpα in cells expressing C/EBPβΔ141-149 was due to a persistent recruitment of HDAC1 to the C/ebpα promoter after glucocorticoid treatment. Together, these results suggest that amino acids 141-149 of C/EBPβ act as a positive regulatory domain required for maximum transcriptional activity.

  15. Identification and characterization of histone deacetylases in tomato (Solanum lycopersicum)

    PubMed Central

    Zhao, Linmao; Lu, Jingxia; Zhang, Jianxia; Wu, Pei-Ying; Yang, Songguang; Wu, Keqiang

    2015-01-01

    Histone acetylation and deacetylation at the N-terminus of histone tails play crucial roles in the regulation of eukaryotic gene activity. Histone acetylation and deacetylation are catalyzed by histone acetyltransferases and histone deacetylases (HDACs), respectively. A growing number of studies have demonstrated the importance of histone deacetylation/acetylation on genome stability, transcriptional regulation, development and response to stress in Arabidopsis. However, the biological functions of HDACs in tomato have not been investigated previously. Fifteen HDACs identified from tomato (Solanum lycopersicum) can be grouped into RPD3/HDA1, SIR2 and HD2 families based on phylogenetic analysis. Meanwhile, 10 members of the RPD3/HDA1 family can be further subdivided into four groups, namely Class I, Class II, Class III, and Class IV. High similarities of protein sequences and conserved domains were identified among SlHDACs and their homologs in Arabidopsis. Most SlHDACs were expressed in all tissues examined with different transcript abundance. Transient expression in Arabidopsis protoplasts showed that SlHDA8, SlHDA1, SlHDA5, SlSRT1 and members of the HD2 family were localized to the nucleus, whereas SlHDA3 and SlHDA4 were localized in both the cytoplasm and nucleus. The difference in the expression patterns and subcellular localization of SlHDACs suggest that they may play distinct functions in tomato. Furthermore, we found that three members of the RPD3/HDA1 family, SlHDA1, SIHDA3 and SlHDA4, interacted with TAG1 (TOMATO AGAMOUS1) and TM29 (TOMATO MADS BOX29), two MADS-box proteins associated with tomato reproductive development, indicating that these HDACs may be involved in gene regulation in reproductive development. PMID:25610445

  16. Aberrant Expression of Histone Deacetylases 4 in Cognitive Disorders: Molecular Mechanisms and a Potential Target

    PubMed Central

    Wu, Yili; Hou, Fei; Wang, Xin; Kong, Qingsheng; Han, Xiaolin; Bai, Bo

    2016-01-01

    Histone acetylation is a major mechanism of chromatin remodeling, contributing to epigenetic regulation of gene transcription. Histone deacetylases (HDACs) are involved in both physiological and pathological conditions by regulating the status of histone acetylation. Although histone deacetylase 4 (HDAC4), a member of the HDAC family, may lack HDAC activity, it is actively involved in regulating the transcription of genes involved in synaptic plasticity, neuronal survival, and neurodevelopment by interacting with transcription factors, signal transduction molecules and HDAC3, another member of the HDAC family. HDAC4 is highly expressed in brain and its homeostasis is crucial for the maintenance of cognitive function. Accumulated evidence shows that HDAC4 expression is dysregulated in several brain disorders, including neurodegenerative diseases and mental disorders. Moreover, cognitive impairment is a characteristic feature of these diseases. It indicates that aberrant HDAC4 expression plays a pivotal role in cognitive impairment of these disorders. This review aims to describe the current understanding of HDAC4’s role in the maintenance of cognitive function and its dysregulation in neurodegenerative diseases and mental disorders, discuss underlying molecular mechanisms, and provide an outlook into targeting HDAC4 as a potential therapeutic approach to rescue cognitive impairment in these diseases. PMID:27847464

  17. A circadian rhythm orchestrated by histone deacetylase 3 controls hepatic lipid metabolism.

    PubMed

    Feng, Dan; Liu, Tao; Sun, Zheng; Bugge, Anne; Mullican, Shannon E; Alenghat, Theresa; Liu, X Shirley; Lazar, Mitchell A

    2011-03-11

    Disruption of the circadian clock exacerbates metabolic diseases, including obesity and diabetes. We show that histone deacetylase 3 (HDAC3) recruitment to the genome displays a circadian rhythm in mouse liver. Histone acetylation is inversely related to HDAC3 binding, and this rhythm is lost when HDAC3 is absent. Although amounts of HDAC3 are constant, its genomic recruitment in liver corresponds to the expression pattern of the circadian nuclear receptor Rev-erbα. Rev-erbα colocalizes with HDAC3 near genes regulating lipid metabolism, and deletion of HDAC3 or Rev-erbα in mouse liver causes hepatic steatosis. Thus, genomic recruitment of HDAC3 by Rev-erbα directs a circadian rhythm of histone acetylation and gene expression required for normal hepatic lipid homeostasis.

  18. Properties of the yeast nuclear histone deacetylase.

    PubMed Central

    Sanchez del Pino, M M; Lopez-Rodas, G; Sendra, R; Tordera, V

    1994-01-01

    A nuclear histone deacetylase from yeast was partially purified and some of its characteristics were studied. Histone deacetylase activity was stimulated in vitro by high-mobility-group nonhistone chromatin proteins 1 and 2 and ubiquitin and inhibited by spermine and spermidine, whereas n-butyrate had no significant inhibitory effect. Like the mammalian enzyme, partially purified histone deacetylase from yeast was strongly inhibited by trichostatin A. However, in crude extract preparations the yeast enzyme was not inhibited and treatment with trichostatin in vivo did not show any effect, either on the histone acetylation level or on cell viability. At low ionic strength, the enzyme can be isolated as a complex of high molecular mass that is much less inhibited by trichostatin A than is partially purified histone deacetylase activity. Furthermore, radiolabelled oligonucleosomes were more efficiently deacetylated by the complex than by the low-molecular-mass form of the enzyme. The histone deacetylase activity was separated from a polyamine deacetylase activity and its specificity studied. Using h.p.l.c.-purified core histone species as substrate, histone deacetylase from yeast is able to deacetylate all core histones with a slight preference for H3. Our results support the idea that the yeast histone deacetylase may act as a high-molecular-mass complex in vivo. Images Figure 3 PMID:7980438

  19. Deacetylase inhibitors dissociate the histone-targeting ING2 subunit from the Sin3 complex

    PubMed Central

    Smith, Karen T.; Martin-Brown, Skylar A.; Florens, Laurence; Washburn, Michael P.; Workman, Jerry L.

    2010-01-01

    Summary Histone deacetylase (HDAC) inhibitors are in clinical development for several diseases, including cancers and neurodegenerative disorders. HDACs1 and 2 are among the targets of these inhibitors and are part of multisubunit protein complexes. HDAC inhibitors (HDACi) block the activity of HDACs by chelating a zinc molecule in their catalytic sites. It is not known if the inhibitors have any additional functional effects on the multisubunit HDAC complexes. Here, we find that suberoylanilide hydroxamic acid (SAHA), the recently FDA approved HDACi, causes the dissociation of the PHD-finger containing ING2 subunit from the Sin3 deacetylase complex. Loss of ING2 disrupts the in vivo binding of the Sin3 complex to the p21 promoter, an important target gene for cell growth inhibition by SAHA. Our findings reveal a new molecular mechanism by which HDAC inhibitors disrupt deacetylase function. PMID:20142042

  20. Deletion of histone deacetylase 3 reveals critical roles in S phase progression and DNA damage control.

    PubMed

    Bhaskara, Srividya; Chyla, Brenda J; Amann, Joseph M; Knutson, Sarah K; Cortez, David; Sun, Zu-Wen; Hiebert, Scott W

    2008-04-11

    Histone deacetylases (HDACs) are enzymes that modify key residues in histones to regulate chromatin architecture, and they play a vital role in cell survival, cell-cycle progression, and tumorigenesis. To understand the function of Hdac3, a critical component of the N-CoR/SMRT repression complex, a conditional allele of Hdac3 was engineered. Cre-recombinase-mediated inactivation of Hdac3 led to a delay in cell-cycle progression, cell-cycle-dependent DNA damage, and apoptosis in mouse embryonic fibroblasts (MEFs). While no overt defects in mitosis were observed in Hdac3-/- MEFs, including normal H3Ser10 phosphorylation, DNA damage was observed in Hdac3-/- interphase cells, which appears to be associated with defective DNA double-strand break repair. Moreover, we noted that Hdac3-/- MEFs were protected from DNA damage when quiescent, which may provide a mechanistic basis for the action of HDAC inhibitors on cycling tumor cells.

  1. Dynamic phosphorylation of Histone Deacetylase 1 by Aurora kinases during mitosis regulates zebrafish embryos development

    PubMed Central

    Loponte, Sara; Segré, Chiara V.; Senese, Silvia; Miccolo, Claudia; Santaguida, Stefano; Deflorian, Gianluca; Citro, Simona; Mattoscio, Domenico; Pisati, Federica; Moser, Mirjam A.; Visintin, Rosella; Seiser, Christian; Chiocca, Susanna

    2016-01-01

    Histone deacetylases (HDACs) catalyze the removal of acetyl molecules from histone and non-histone substrates playing important roles in chromatin remodeling and control of gene expression. Class I HDAC1 is a critical regulator of cell cycle progression, cellular proliferation and differentiation during development; it is also regulated by many post-translational modifications (PTMs). Herein we characterize a new mitosis-specific phosphorylation of HDAC1 driven by Aurora kinases A and B. We show that this phosphorylation affects HDAC1 enzymatic activity and it is critical for the maintenance of a proper proliferative and developmental plan in a complex organism. Notably, we find that Aurora-dependent phosphorylation of HDAC1 regulates histone acetylation by modulating the expression of genes directly involved in the developing zebrafish central nervous system. Our data represent a step towards the comprehension of HDAC1 regulation by its PTM code, with important implications in unravelling its roles both in physiology and pathology. PMID:27458029

  2. The multifaceted influence of histone deacetylases on DNA damage signalling and DNA repair

    PubMed Central

    Roos, Wynand Paul; Krumm, Andrea

    2016-01-01

    Histone/protein deacetylases play multiple roles in regulating gene expression and protein activation and stability. Their deregulation during cancer initiation and progression cause resistance to therapy. Here, we review the role of histone deacetylases (HDACs) and the NAD+ dependent sirtuins (SIRTs) in the DNA damage response (DDR). These lysine deacetylases contribute to DNA repair by base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), non-homologous end joining (NHEJ), homologous recombination (HR) and interstrand crosslink (ICL) repair. Furthermore, we discuss possible mechanisms whereby these histone/protein deacetylases facilitate the switch between DNA double-strand break (DSB) repair pathways, how SIRTs play a central role in the crosstalk between DNA repair and cell death pathways due to their dependence on NAD+, and the influence of small molecule HDAC inhibitors (HDACi) on cancer cell resistance to genotoxin based therapies. Throughout the review, we endeavor to identify the specific HDAC targeted by HDACi leading to therapy sensitization. PMID:27738139

  3. Targeting macrophage Histone deacetylase 3 stabilizes atherosclerotic lesions

    PubMed Central

    Hoeksema, Marten A; Gijbels, Marion JJ; Van den Bossche, Jan; van der Velden, Saskia; Sijm, Ayestha; Neele, Annette E; Seijkens, Tom; Stöger, J Lauran; Meiler, Svenja; Boshuizen, Marieke CS; Dallinga-Thie, Geesje M; Levels, Johannes HM; Boon, Louis; Mullican, Shannon E; Spann, Nathanael J; Cleutjens, Jack P; Glass, Chris K; Lazar, Mitchell A; de Vries, Carlie JM; Biessen, Erik AL; Daemen, Mat JAP; Lutgens, Esther; de Winther, Menno PJ

    2014-01-01

    Macrophages are key immune cells found in atherosclerotic plaques and critically shape atherosclerotic disease development. Targeting the functional repertoire of macrophages may hold novel approaches for future atherosclerosis management. Here, we describe a previously unrecognized role of the epigenomic enzyme Histone deacetylase 3 (Hdac3) in regulating the atherosclerotic phenotype of macrophages. Using conditional knockout mice, we found that myeloid Hdac3 deficiency promotes collagen deposition in atherosclerotic lesions and thus induces a stable plaque phenotype. Also, macrophages presented a switch to anti-inflammatory wound healing characteristics and showed improved lipid handling. The pro-fibrotic phenotype was directly linked to epigenetic regulation of the Tgfb1 locus upon Hdac3 deletion, driving smooth muscle cells to increased collagen production. Moreover, in humans, HDAC3 was the sole Hdac upregulated in ruptured atherosclerotic lesions, Hdac3 associated with inflammatory macrophages, and HDAC3 expression inversely correlated with pro-fibrotic TGFB1 expression. Collectively, we show that targeting the macrophage epigenome can improve atherosclerosis outcome and we identify Hdac3 as a potential novel therapeutic target in cardiovascular disease. PMID:25007801

  4. Nitric Oxide Modulates Histone Acetylation at Stress Genes by Inhibition of Histone Deacetylases1[OPEN

    PubMed Central

    Mengel, Alexander; Ageeva, Alexandra; Durner, Jörg

    2017-01-01

    Histone acetylation, which is an important mechanism to regulate gene expression, is controlled by the opposing action of histone acetyltransferases and histone deacetylases (HDACs). In animals, several HDACs are subjected to regulation by nitric oxide (NO); in plants, however, it is unknown whether NO affects histone acetylation. We found that treatment with the physiological NO donor S-nitrosoglutathione (GSNO) increased the abundance of several histone acetylation marks in Arabidopsis (Arabidopsis thaliana), which was strongly diminished in the presence of the NO scavenger 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide. This increase was likely triggered by NO-dependent inhibition of HDAC activity, since GSNO and S-nitroso-N-acetyl-dl-penicillamine significantly and reversibly reduced total HDAC activity in vitro (in nuclear extracts) and in vivo (in protoplasts). Next, genome-wide H3K9/14ac profiles in Arabidopsis seedlings were generated by chromatin immunoprecipitation sequencing, and changes induced by GSNO, GSNO/2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide or trichostatin A (an HDAC inhibitor) were quantified, thereby identifying genes that display putative NO-regulated histone acetylation. Functional classification of these genes revealed that many of them are involved in the plant defense response and the abiotic stress response. Furthermore, salicylic acid, which is the major plant defense hormone against biotrophic pathogens, inhibited HDAC activity and increased histone acetylation by inducing endogenous NO production. These data suggest that NO affects histone acetylation by targeting and inhibiting HDAC complexes, resulting in the hyperacetylation of specific genes. This mechanism might operate in the plant stress response by facilitating the stress-induced transcription of genes. PMID:27980017

  5. Use of the nitrile oxide cycloaddition (NOC) reaction for molecular probe generation: a new class of enzyme selective histone deacetylase inhibitors (HDACIs) showing picomolar activity at HDAC6.

    PubMed

    Kozikowski, Alan P; Tapadar, Subhasish; Luchini, Doris N; Kim, Ki Hwan; Billadeau, Daniel D

    2008-08-14

    A series of hydroxamate based HDAC inhibitors containing a phenylisoxazole as the CAP group has been synthesized using nitrile oxide cycloaddition chemistry. An HDAC6 selective inhibitor having a potency of approximately 2 picomolar was identified. Some of the compounds were examined for their ability to block pancreatic cancer cell growth and found to be about 10-fold more potent than SAHA. This research provides valuable, new molecular probes for use in exploring HDAC biology.

  6. O-GlcNAcylation of histone deacetylases 1 in hepatocellular carcinoma promotes cancer progression.

    PubMed

    Zhu, Guizhou; Tao, Tao; Zhang, Dongmei; Liu, Xiaojuan; Qiu, Huiyuan; Han, LiJian; Xu, Zhiwei; Xiao, Ying; Cheng, Chun; Shen, Aiguo

    2016-08-01

    Hepatocellular carcinoma (HCC) is a malignant tumor originating in the liver. Previous studies have indicated that O-GlcNAc transferase (OGT) and histone deacetylase-1 (HDAC1) play important roles in the pathogenesis of HCC. In the present study, we investigated the physical link between OGT and HDAC1. The O-GlcNAcylation of HDAC1 is overexpressed in HCC. We found that HDAC1 has two major sites of O-GlcNAcylation in its histone deacetylase domain. HDAC1 O-GlcNAcylation increases the activated phosphorylation of HDAC1, which enhances its enzyme activity. HDAC1 O-GlcNAc mutants promote the p21 transcription regulation through affecting the acetylation levels of histones from chromosome, and then influence the proliferation of HCC cells. We also found that mutants of O-GlcNAcylation site of HDAC1 affect invasion and migration of HepG2 cells. E-cadherin level is highly up-regulated in HDAC1 O-GlcNAc mutant-treated liver cancer cells, which inhibit the occurrence and development of HCC. Our findings suggest that OGT promotes the O-GlcNAc modification of HDAC1in the development of HCC. Therefore, inhibiting O-GlcNAcylation of HDAC1 may repress the progression of HCC.

  7. Histone deacetylase 6 promotes growth of glioblastoma through inhibition of SMAD2 signaling.

    PubMed

    Li, Shun; Liu, Xiao; Chen, Xiangrong; Zhang, Liu; Wang, Xiangyu

    2015-12-01

    Histone deacetylases (HDACs) play a role in the tumorigenesis of glioblastoma multiforme (GBM), whereas the underlying mechanism has not been elucidated. Here, we reported significantly higher HDAC6 levels in GBM from the patients. GBM cell growth was significantly inhibited by ACY-1215, a specific HDAC6 inhibitor. Further analyses show that HDAC6 may promote growth of GBM cells through inhibition of SMAD2 phosphorylation to downregulate p21. Thus, our data demonstrate a previously unrecognized regulation pathway in that HDAC6 increases GBM growth through attenuating transforming growth factor β (TGFβ) receptor signaling.

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

    PubMed

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

    2012-11-01

    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.

  9. Histone deacetylase inhibitors: understanding a new wave of anticancer agents.

    PubMed

    Villar-Garea, Ana; Esteller, Manel

    2004-11-01

    Cancer is as much an epigenetic disease as it is a genetic and cytogenetic disease. The discovery that drastic changes in DNA methylation and histone modifications are commonly found in human tumors has inspired various laboratories and pharmaceutical companies to develop and study epigenetic drugs. One of the most promising groups of agents is the inhibitors of histone deacetylases (HDACs), which have different biochemical and biologic properties but have a single common activity: induction of acetylation in histones, the key proteins in nucleosome and chromatin structure. One of the main mechanisms of action of HDAC inhibitors is the transcriptional reactivation of dormant tumor-suppressor genes, such as p21WAF1. However, their pleiotropic nature leaves open the possibility that their well-known differentiation, cell-cycle arrest and apoptotic properties are also involved in other functions associated with HDAC inhibition. Many phase I clinical trials indicate that HDAC inhibitors appear to be well-tolerated drugs. Thus, the field is ready for rigorous biologic and clinical scrutiny to validate the therapeutic potential of these drugs. Our current data indicate that the use of HDAC inhibitors, probably in association with classical chemotherapy drugs or in combination with DNA-demethylating agents, could be promising for cancer patients.

  10. Role of histone deacetylases in gene regulation at nuclear lamina.

    PubMed

    Milon, Beatrice C; Cheng, Haibo; Tselebrovsky, Mikhail V; Lavrov, Sergei A; Nenasheva, Valentina V; Mikhaleva, Elena A; Shevelyov, Yuri Y; Nurminsky, Dmitry I

    2012-01-01

    Theoretical models suggest that gene silencing at the nuclear periphery may involve "closing" of chromatin by transcriptional repressors, such as histone deacetylases (HDACs). Here we provide experimental evidence confirming these predictions. Histone acetylation, chromatin compactness, and gene repression in lamina-interacting multigenic chromatin domains were analyzed in Drosophila S2 cells in which B-type lamin, diverse HDACs, and lamina-associated proteins were downregulated by dsRNA. Lamin depletion resulted in decreased compactness of the repressed multigenic domain associated with its detachment from the lamina and enhanced histone acetylation. Our data reveal the major role for HDAC1 in mediating deacetylation, chromatin compaction, and gene silencing in the multigenic domain, and an auxiliary role for HDAC3 that is required for retention of the domain at the lamina. These findings demonstrate the manifold and central involvement of class I HDACs in regulation of lamina-associated genes, illuminating a mechanism by which these enzymes can orchestrate normal and pathological development.

  11. Role of Histone Deacetylases in Gene Regulation at Nuclear Lamina

    PubMed Central

    Milon, Beatrice C.; Cheng, Haibo; Tselebrovsky, Mikhail V.; Lavrov, Sergei A.; Nenasheva, Valentina V.; Mikhaleva, Elena A.; Shevelyov, Yuri Y.; Nurminsky, Dmitry I.

    2012-01-01

    Theoretical models suggest that gene silencing at the nuclear periphery may involve “closing” of chromatin by transcriptional repressors, such as histone deacetylases (HDACs). Here we provide experimental evidence confirming these predictions. Histone acetylation, chromatin compactness, and gene repression in lamina-interacting multigenic chromatin domains were analyzed in Drosophila S2 cells in which B-type lamin, diverse HDACs, and lamina-associated proteins were downregulated by dsRNA. Lamin depletion resulted in decreased compactness of the repressed multigenic domain associated with its detachment from the lamina and enhanced histone acetylation. Our data reveal the major role for HDAC1 in mediating deacetylation, chromatin compaction, and gene silencing in the multigenic domain, and an auxiliary role for HDAC3 that is required for retention of the domain at the lamina. These findings demonstrate the manifold and central involvement of class I HDACs in regulation of lamina-associated genes, illuminating a mechanism by which these enzymes can orchestrate normal and pathological development. PMID:23226217

  12. Histone Deacetylases and Their Inhibition in Candida Species

    PubMed Central

    Garnaud, Cécile; Champleboux, Morgane; Maubon, Danièle; Cornet, Muriel; Govin, Jérôme

    2016-01-01

    Fungi are generally benign members of the human mucosal flora or live as saprophytes in the environment. However, they can become pathogenic, leading to invasive and life threatening infections in vulnerable patients. These invasive fungal infections are regarded as a major public health problem on a similar scale to tuberculosis or malaria. Current treatment for these infections is based on only four available drug classes. This limited therapeutic arsenal and the emergence of drug-resistant strains are a matter of concern due to the growing number of patients to be treated, and new therapeutic strategies are urgently needed. Adaptation of fungi to drug pressure involves transcriptional regulation, in which chromatin dynamics and histone modifications play a major role. Histone deacetylases (HDACs) remove acetyl groups from histones and actively participate in controlling stress responses. HDAC inhibition has been shown to limit fungal development, virulence, biofilm formation, and dissemination in the infected host, while also improving the efficacy of existing antifungal drugs toward Candida spp. In this article, we review the functional roles of HDACs and the biological effects of HDAC inhibitors on Candida spp., highlighting the correlations between their pathogenic effects in vitro and in vivo. We focus on how HDAC inhibitors could be used to treat invasive candidiasis while also reviewing recent developments in their clinical evaluation. PMID:27547205

  13. Non-sirtuin histone deacetylases in the control of cardiac aging.

    PubMed

    Ferguson, Bradley S; McKinsey, Timothy A

    2015-06-01

    Histone deacetylases (HDACs) catalyze the removal of acetyl-groups from lysine residues within nucelosomal histone tails and thousands of non-histone proteins. The 18 mammalian HDACs are grouped into four classes. Classes I, II and IV HDACs employ zinc as a co-factor for catalytic activity, while class III HDACs (also known as sirtuins) require NAD+ for enzymatic function. Small molecule inhibitors of zinc-dependent HDACs are efficacious in multiple pre-clinical models of pressure overload and ischemic cardiomyopathy, reducing pathological hypertrophy and fibrosis, and improving contractile function. Emerging data have revealed numerous mechanisms by which HDAC inhibitors benefit the heart, including suppression of oxidative stress and inflammation, inhibition of MAP kinase signaling, and enhancement of cardiac protein aggregate clearance and autophagic flux. Here, we summarize recent findings with zinc-dependent HDACs and HDAC inhibitors in the heart, focusing on newly described functions for distinct HDAC isoforms (e.g. HDAC2, HDAC3 and HDAC6). Potential for pharmacological HDAC inhibition as a means of treating age-related cardiac dysfunction is also discussed. This article is part of a Special Issue entitled: CV Aging.

  14. Mice lacking histone deacetylase 6 have hyperacetylated tubulin but are viable and develop normally.

    PubMed

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

    2008-03-01

    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 multisubstrate protein deacetylase that can act on acetylated histone tails, alpha-tubulin and Hsp90. To investigate the in vivo functions of HDAC6 and the relevance of tubulin acetylation/deacetylation, we targeted the HDAC6 gene by homologous recombination in embryonic stem cells and generated knockout mice. HDAC6-deficient mice are viable and fertile and show hyperacetylated tubulin in most tissues. The highest level of expression of HDAC6 is seen in the testis, yet development and function of this organ are normal in the absence of HDAC6. Likewise, lymphoid development is normal, but the immune response is moderately affected. Furthermore, the lack of HDAC6 results in a small increase in cancellous bone mineral density, indicating that this deacetylase plays a minor role in bone biology. HDAC6-deficient mouse embryonic fibroblasts show apparently normal microtubule organization and stability and also show increased Hsp90 acetylation correlating with impaired Hsp90 function. Collectively, these data demonstrate that mice survive well without HDAC6 and that tubulin hyperacetylation is not detrimental to normal mammalian development.

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

    ERIC Educational Resources Information Center

    Mahgoub, Melissa; Monteggia, Lisa M.

    2014-01-01

    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…

  16. Ex vivo response to histone deacetylase (HDAC) inhibitors of the HIV long terminal repeat (LTR) derived from HIV-infected patients on antiretroviral therapy.

    PubMed

    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; Churchill, Melissa J; Lewin, Sharon R

    2014-01-01

    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.

  17. Hypothalamic leptin action is mediated by histone deacetylase 5

    PubMed Central

    Kabra, Dhiraj G.; Pfuhlmann, Katrin; García-Cáceres, Cristina; Schriever, Sonja C.; Casquero García, Veronica; Kebede, Adam Fiseha; Fuente-Martin, Esther; Trivedi, Chitrang; Heppner, Kristy; Uhlenhaut, N. Henriette; Legutko, Beata; Kabra, Uma D.; Gao, Yuanqing; Yi, Chun-Xia; Quarta, Carmelo; Clemmensen, Christoffer; Finan, Brian; Müller, Timo D.; Meyer, Carola W.; Paez-Pereda, Marcelo; Stemmer, Kerstin; Woods, Stephen C.; Perez-Tilve, Diego; Schneider, Robert; Olson, Eric N.; Tschöp, Matthias H.; Pfluger, Paul T.

    2016-01-01

    Hypothalamic leptin signalling has a key role in food intake and energy-balance control and is often impaired in obese individuals. Here we identify histone deacetylase 5 (HDAC5) as a regulator of leptin signalling and organismal energy balance. Global HDAC5 KO mice have increased food intake and greater diet-induced obesity when fed high-fat diet. Pharmacological and genetic inhibition of HDAC5 activity in the mediobasal hypothalamus increases food intake and modulates pathways implicated in leptin signalling. We show HDAC5 directly regulates STAT3 localization and transcriptional activity via reciprocal STAT3 deacetylation at Lys685 and phosphorylation at Tyr705. In vivo, leptin sensitivity is substantially impaired in HDAC5 loss-of-function mice. Hypothalamic HDAC5 overexpression improves leptin action and partially protects against HFD-induced leptin resistance and obesity. Overall, our data suggest that hypothalamic HDAC5 activity is a regulator of leptin signalling that adapts food intake and body weight to our dietary environment. PMID:26923837

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

    SciTech Connect

    Song, Young Mi; Kim, You Sun; Kim, Dooil; Lee, Dae Sil; Kwon, Ho Jeong . E-mail: kwonhj@yonsei.ac.kr

    2007-09-14

    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.

  19. Comparative modeling and benchmarking data sets for human histone deacetylases and sirtuin families.

    PubMed

    Xia, Jie; Tilahun, Ermias Lemma; Kebede, Eyob Hailu; Reid, Terry-Elinor; Zhang, Liangren; Wang, Xiang Simon

    2015-02-23

    Histone deacetylases (HDACs) are an important class of drug targets for the treatment of cancers, neurodegenerative diseases, and other types of diseases. Virtual screening (VS) has become fairly effective approaches for drug discovery of novel and highly selective histone deacetylase inhibitors (HDACIs). To facilitate the process, we constructed maximal unbiased benchmarking data sets for HDACs (MUBD-HDACs) using our recently published methods that were originally developed for building unbiased benchmarking sets for ligand-based virtual screening (LBVS). The MUBD-HDACs cover all four classes including Class III (Sirtuins family) and 14 HDAC isoforms, composed of 631 inhibitors and 24609 unbiased decoys. Its ligand sets have been validated extensively as chemically diverse, while the decoy sets were shown to be property-matching with ligands and maximal unbiased in terms of "artificial enrichment" and "analogue bias". We also conducted comparative studies with DUD-E and DEKOIS 2.0 sets against HDAC2 and HDAC8 targets and demonstrate that our MUBD-HDACs are unique in that they can be applied unbiasedly to both LBVS and SBVS approaches. In addition, we defined a novel metric, i.e. NLBScore, to detect the "2D bias" and "LBVS favorable" effect within the benchmarking sets. In summary, MUBD-HDACs are the only comprehensive and maximal-unbiased benchmark data sets for HDACs (including Sirtuins) that are available so far. MUBD-HDACs are freely available at http://www.xswlab.org/ .

  20. Novel Antiproliferative Chimeric Compounds with Marked Histone Deacetylase Inhibitory Activity

    PubMed Central

    2014-01-01

    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

  1. Histone Deacetylases in Bone Development and Skeletal Disorders

    PubMed Central

    Bradley, Elizabeth W.; Carpio, Lomeli R.; van Wijnen, Andre J.; McGee-Lawrence, Meghan E.; Westendorf, Jennifer J.

    2015-01-01

    Histone deacetylases (Hdacs) are conserved enzymes that remove acetyl groups from lysine side chains in histones and other proteins. Eleven of the 18 Hdacs encoded by the human and mouse genomes depend on Zn2+ for enzymatic activity, while the other 7, the sirtuins (Sirts), require NAD2+. Collectively, Hdacs and Sirts regulate numerous cellular and mitochondrial processes including gene transcription, DNA repair, protein stability, cytoskeletal dynamics, and signaling pathways to affect both development and aging. Of clinical relevance, Hdacs inhibitors are United States Food and Drug Administration-approved cancer therapeutics and are candidate therapies for other common diseases including arthritis, diabetes, epilepsy, heart disease, HIV infection, neurodegeneration, and numerous aging-related disorders. Hdacs and Sirts influence skeletal development, maintenance of mineral density and bone strength by affecting intramembranous and endochondral ossification, as well as bone resorption. With few exceptions, inhibition of Hdac or Sirt activity though either loss-of-function mutations or prolonged chemical inhibition has negative and/or toxic effects on skeletal development and bone mineral density. Specifically, Hdac/Sirt suppression causes abnormalities in physiological development such as craniofacial dimorphisms, short stature, and bone fragility that are associated with several human syndromes or diseases. In contrast, activation of Sirts may protect the skeleton from aging and immobilization-related bone loss. This knowledge may prolong healthspan and prevent adverse events caused by epigenetic therapies that are entering the clinical realm at an unprecedented rate. In this review, we summarize the general properties of Hdacs/Sirts and the research that has revealed their essential functions in bone forming cells (e.g., osteoblasts and chondrocytes) and bone resorbing osteoclasts. Finally, we offer predictions on future research in this area and the utility of

  2. Histone Deacetylase Inhibition Restores Retinal Pigment Epithelium Function in Hyperglycemia

    PubMed Central

    Desjardins, Danielle; Liu, Yueying; Crosson, Craig E.; Ablonczy, Zsolt

    2016-01-01

    In diabetic individuals, macular edema is a major cause of vision loss. This condition is refractory to insulin therapy and has been attributed to metabolic memory. The retinal pigment epithelium (RPE) is central to maintaining fluid balance in the retina, and this function is compromised by the activation of advanced glycation end-product receptors (RAGE). Here we provide evidence that acute administration of the RAGE agonist, glycated-albumin (gAlb) or vascular endothelial growth factor (VEGF), increased histone deacetylase (HDAC) activity in RPE cells. The administration of the class I/II HDAC inhibitor, trichostatin-A (TSA), suppressed gAlb-induced reductions in RPE transepithelial resistance (in vitro) and fluid transport (in vivo). Systemic TSA also restored normal RPE fluid transport in rats with subchronic hyperglycemia. Both gAlb and VEGF increased HDAC activity and reduced acetyl-α-tubulin levels. Tubastatin-A, a relatively specific antagonist of HDAC6, inhibited gAlb-induced changes in RPE cell resistance. These data are consistent with the idea that RPE dysfunction following exposure to gAlb, VEGF, or hyperglycemia is associated with increased HDAC6 activity and decreased acetyl-α-tubulin. Therefore, we propose inhibiting HDAC6 in the RPE as a potential therapy for preserving normal fluid homeostasis in the hyperglycemic retina. PMID:27617745

  3. Screening of selective histone deacetylase inhibitors by proteochemometric modeling

    PubMed Central

    2012-01-01

    Background Histone deacetylase (HDAC) is a novel target for the treatment of cancer and it can be classified into three classes, i.e., classes I, II, and IV. The inhibitors selectively targeting individual HDAC have been proved to be the better candidate antitumor drugs. To screen selective HDAC inhibitors, several proteochemometric (PCM) models based on different combinations of three kinds of protein descriptors, two kinds of ligand descriptors and multiplication cross-terms were constructed in our study. Results The results show that structure similarity descriptors are better than sequence similarity descriptors and geometry descriptors in the leftacterization of HDACs. Furthermore, the predictive ability was not improved by introducing the cross-terms in our models. Finally, a best PCM model based on protein structure similarity descriptors and 32-dimensional general descriptors was derived (R2 = 0.9897, Qtest2 = 0.7542), which shows a powerful ability to screen selective HDAC inhibitors. Conclusions Our best model not only predict the activities of inhibitors for each HDAC isoform, but also screen and distinguish class-selective inhibitors and even more isoform-selective inhibitors, thus it provides a potential way to discover or design novel candidate antitumor drugs with reduced side effect. PMID:22913517

  4. Histone Deacetylase 7 Promotes Toll-like Receptor 4-dependent Proinflammatory Gene Expression in Macrophages*

    PubMed Central

    Shakespear, Melanie R.; Hohenhaus, Daniel M.; Kelly, Greg M.; Kamal, Nabilah A.; Gupta, Praveer; Labzin, Larisa I.; Schroder, Kate; Garceau, Valerie; Barbero, Sheila; Iyer, Abishek; Hume, David A.; Reid, Robert C.; Irvine, Katharine M.; Fairlie, David P.; Sweet, Matthew J.

    2013-01-01

    Broad-spectrum inhibitors of histone deacetylases (HDACs) constrain Toll-like receptor (TLR)-inducible production of key proinflammatory mediators. Here we investigated HDAC-dependent inflammatory responses in mouse macrophages. Of the classical Hdacs, Hdac7 was expressed at elevated levels in inflammatory macrophages (thioglycollate-elicited peritoneal macrophages) as compared with bone marrow-derived macrophages and the RAW264 cell line. Overexpression of a specific, alternatively spliced isoform of Hdac7 lacking the N-terminal 22 amino acids (Hdac7-u), but not the Refseq Hdac7 (Hdac7-s), promoted LPS-inducible expression of Hdac-dependent genes (Edn1, Il-12p40, and Il-6) in RAW264 cells. A novel class IIa-selective HDAC inhibitor reduced recombinant human HDAC7 enzyme activity as well as TLR-induced production of inflammatory mediators in thioglycollate-elicited peritoneal macrophages. Both LPS and Hdac7-u up-regulated the activity of the Edn1 promoter in an HDAC-dependent fashion in RAW264 cells. A hypoxia-inducible factor (HIF) 1 binding site in this promoter was required for HDAC-dependent TLR-inducible promoter activity and for Hdac7- and HIF-1α-mediated trans-activation. Coimmunoprecipitation assays showed that both Hdac7-u and Hdac7-s interacted with HIF-1α, whereas only Hdac7-s interacted with the transcriptional repressor CtBP1. Thus, Hdac7-u positively regulates HIF-1α-dependent TLR signaling in macrophages, whereas an interaction with CtBP1 likely prevents Hdac7-s from exerting this effect. Hdac7 may represent a potential inflammatory disease target. PMID:23853092

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

    SciTech Connect

    Zhuang, Yan; Nguyen, Hong T.; Lasky, Joseph A.; Cao, Subing; Li, Cui; Hu, Jiyao; Guo, Xinyue; Burow, Matthew E.; Shan, Bin

    2010-02-19

    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.

  6. Histone Deacetylase 6 Regulates Bladder Architecture and Host Susceptibility to Uropathogenic Escherichia coli

    PubMed Central

    Lewis, Adam J.; Dhakal, Bijaya K.; Liu, Ting; Mulvey, Matthew A.

    2016-01-01

    Histone deacetylase 6 (HDAC6) is a non-canonical, mostly cytosolic histone deacetylase that has a variety of interacting partners and substrates. Previous work using cell-culture based assays coupled with pharmacological inhibitors and gene-silencing approaches indicated that HDAC6 promotes the actin- and microtubule-dependent invasion of host cells by uropathogenic Escherichia coli (UPEC). These facultative intracellular pathogens are the major cause of urinary tract infections. Here, we examined the involvement of HDAC6 in bladder colonization by UPEC using HDAC6 knockout mice. Though UPEC was unable to invade HDAC6−/− cells in culture, the bacteria had an enhanced ability to colonize the bladders of mice that lacked HDAC6. This effect was transient, and by six hours post-inoculation bacterial titers in the HDAC6−/− mice were reduced to levels seen in wild type control animals. Subsequent analyses revealed that the mutant mice had greater bladder volume capacity and fluid retention, along with much higher levels of acetylated α-tubulin. In addition, infiltrating neutrophils recovered from the HDAC6−/− bladder harbored significantly more viable bacteria than their wild type counterparts. Cumulatively, these changes may negate any inhibitory effects that the lack of HDAC6 has on UPEC entry into individual host cells, and suggest roles for HDAC6 in other urological disorders such as urinary retention. PMID:26907353

  7. Computational identification of novel histone deacetylase inhibitors by docking based QSAR.

    PubMed

    Nair, Syam B; Teli, Mahesh Kumar; Pradeep, H; Rajanikant, G K

    2012-06-01

    Histone deacetylases (HDACs) are enzymes that modify chromatin structure and contribute to aberrant gene expression in cancer. A series compounds with well-assigned HDAC inhibitory activity was used for docking based 3D-QSAR analysis. The 3D-QSAR acquired had excellent correlation coefficient value (q2=0.753) and high Fisher ratio (F=300.2). A validated pharmacophore model (AAAPR) was employed for virtual screening. After manual selection, molecular docking and further refinement, six compounds with good absorption, distribution, metabolism, and excretion (ADME) properties were selected as potential HDAC inhibitors. Further, the molecular interactions of these inhibitors with the HDAC active site residues were discussed in detail.

  8. Recruitment of CREB1 and Histone Deacetylase 2 (HDAC2) to the Mouse Ltbp-1 Promoter Regulates its Constitutive Expression in a Dioxin Receptor-dependent Manner

    PubMed Central

    Gomez-Duran, Aurea; Ballestar, Esteban; Carvajal-Gonzalez, Jose M.; Marlowe, Jennifer L.; Puga, Alvaro; Esteller, Manel; Fernandez-Salguero, Pedro M.

    2010-01-01

    Latent TGFβ-binding protein 1 (LTBP-1) is a key regulator of TGFβ targeting and activation in the extracellular matrix. LTBP-1 is recognized as a major docking molecule to localize, and possibly to activate, TGFβ in the extracellular matrix. Despite this relevant function, the molecular mechanisms regulating Ltbp-1 transcription remain largely unknown. Previous results from our laboratory revealed that mouse embryonic fibroblasts (MEF) lacking dioxin receptor (AhR) had increased Ltbp-1 mRNA expression and elevated TGFβ activity, suggesting that AhR repressed Ltbp-1 transcription. Here, we have cloned the mouse Ltbp-1 gene promoter and analysed its mechanism of transcriptional repression by AhR. Reporter gene assays, AhR over-expression and site-directed mutagenesis showed that basal Ltbp-1 transcription is AhR-dependent. Chromatin immunoprecipitation (ChIP) and RNA interference (RNAi) revealed that AhR regulates Ltbp-1 transcription by a mechanism involving recruitment of co-activators such as CREB1 and co-repressors such as HDAC2 to the Ltbp-1 promoter. In AhR-expressing (AhR+/+) MEF cells, the recruitment of HDAC1, 2 and 4 correlated with decreased K8H4 acetylation and impaired binding of pCREBSer133 to the Ltbp-1 promoter, likely maintaining a constitutive repressed state. AhR−/− MEF cells had the opposite pattern of HDACs and pCREB1Ser133 binding to Ltbp-1 promoter, and therefore, over-expressed Ltbp-1 mRNA. In agreement, siRNA for HDAC2 increased Ltbp-1 expression and K8H4 acetylation in AhR+/+ but not in AhR−/− MEF cells. We suggest that HDAC2 binding keeps Ltbp-1 promoter repressed in AhR+/+ MEF cells, whereas in AhR-null MEF cells the absence of HDAC2 and the binding of pCREBSer133 allow Ltbp-1 transcription. Thus, epigenetics can contribute to constitutive Ltbp-1 repression by a mechanism requiring AhR activity. PMID:18508077

  9. Histone deacetylase 1 plays a predominant pro-oncogenic role in Eμ-myc driven B cell lymphoma

    PubMed Central

    Pillonel, Vincent; Reichert, Nina; Cao, Chun; Heideman, Marinus R.; Yamaguchi, Teppei; Matthias, Gabriele; Tzankov, Alexandar; Matthias, Patrick

    2016-01-01

    The two histone deacetylases (Hdacs), Hdac1 and Hdac2, are erasers of acetylation marks on histone tails, and are important regulators of gene expression that were shown to play important roles in hematological malignancies. However, several recent studies reported opposing tumor-suppressive or tumor-promoting roles for Hdac1 and Hdac2. Here, we investigated the functional role of Hdac1 and Hdac2 using the Eμ-myc mouse model of B cell lymphoma. We demonstrate that Hdac1 and Hdac2 have a pro-oncogenic role in both Eμ-myc tumorigenesis and tumor maintenance. Hdac1 and Hdac2 promote tumorigenesis in a gene dose-dependent manner, with a predominant function of Hdac1. Our data show that Hdac1 and Hdac2 impact on Eμ-myc B cell proliferation and apoptosis and suggest that a critical level of Hdac activity may be required for Eμ-myc tumorigenesis and proper B cell development. This provides the rationale for utilization of selective Hdac1 and Hdac2 inhibitors in the treatment of hematological malignancies. PMID:27886239

  10. Histone deacetylases govern cellular mechanisms underlying behavioral and synaptic plasticity in the developing and adult brain

    PubMed Central

    Morris, Michael J.; Karra, Aroon S.; Monteggia, Lisa M.

    2010-01-01

    Histone deacetylases (HDACs) are a family of enzymes that alter gene expression patterns by modifying chromatin architecture. There are 11 mammalian HDACs that are classified by homology into four subfamilies, all with distinct expression patterns in brain. Through the use of pharmacological HDAC inhibitors, and more recently HDAC knockout mice, the role of these enzymes in the central nervous system are starting to be elucidated. We will discuss the latest findings on the specific or redundant roles of individual HDACs in brain as well as the impact of HDAC function on complex behavior, with a focus on learning, memory formation, and affective behavior. Potential HDAC-mediated cellular mechanisms underlying those behaviors are discussed. PMID:20555253

  11. Histone deacetylase 1 is required for the development of the zebrafish inner ear

    PubMed Central

    He, Yingzi; Tang, Dongmei; Li, Wenyan; Chai, Renjie; Li, Huawei

    2016-01-01

    Histone deacetylase 1 (HDAC1) has been reported to be important for multiple aspects of normal embryonic development, but little is known about its function in the development of mechanosensory organs. Here, we first confirmed that HDAC1 is expressed in the developing otic vesicles of zebrafish by whole-mount in situ hybridization. Knockdown of HDAC1 using antisense morpholino oligonucleotides in zebrafish embryos induced smaller otic vesicles, abnormal otoliths, malformed or absent semicircular canals, and fewer sensory hair cells. HDAC1 loss of function also caused attenuated expression of a subset of key genes required for otic vesicle formation during development. Morpholino-mediated knockdown of HDAC1 resulted in decreased expression of members of the Fgf family in the otic vesicles, suggesting that HDAC1 is involved in the development of the inner ear through regulation of Fgf signaling pathways. Taken together, our results indicate that HDAC1 plays an important role in otic vesicle formation. PMID:26832938

  12. Inhibitors of Histone Deacetylases Enhance Neurotoxicity of DNA Damage

    PubMed Central

    Vashishta, A.

    2014-01-01

    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

  13. HDACiDB: a database for histone deacetylase inhibitors.

    PubMed

    Murugan, Kasi; Sangeetha, Shanmugasamy; Ranjitha, Shanmugasamy; Vimala, Antony; Al-Sohaibani, Saleh; Rameshkumar, Gopal

    2015-01-01

    An histone deacetylase (HDAC) inhibitor database (HDACiDB) was constructed to enable rapid access to data relevant to the development of epigenetic modulators (HDAC inhibitors [HDACi]), helping bring precision cancer medicine a step closer. Thousands of HDACi targeting HDACs are in various stages of development and are being tested in clinical trials as monotherapy and in combination with other cancer agents. Despite the abundance of HDACi, information resources are limited. Tools for in silico experiments on specific HDACi prediction, for designing and analyzing the generated data, as well as custom-made specific tools and interactive databases, are needed. We have developed an HDACiDB that is a composite collection of HDACi and currently comprises 1,445 chemical compounds, including 419 natural and 1,026 synthetic ones having the potential to inhibit histone deacetylation. Most importantly, it will allow application of Lipinski's rule of five drug-likeness and other physicochemical property-based screening of the inhibitors. It also provides easy access to information on their source of origin, molecular properties, drug likeness, as well as bioavailability with relevant references cited. Being the first comprehensive database on HDACi that contains all known natural and synthetic HDACi, the HDACiDB may help to improve our knowledge concerning the mechanisms of actions of available HDACi and enable us to selectively target individual HDAC isoforms and establish a new paradigm for intelligent epigenetic cancer drug design. The database is freely available on the http://hdacidb.bioinfo.au-kbc.org.in/hdacidb/website.

  14. Histone deacetylases and their role in motor neuron degeneration

    PubMed Central

    Lazo-Gómez, Rafael; Ramírez-Jarquín, Uri N.; Tovar-y-Romo, Luis B.; Tapia, Ricardo

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease, characterized by the progressive loss of motor neurons. The cause of this selective neuronal death is unknown, but transcriptional dysregulation is recently emerging as an important factor. The physical substrate for the regulation of the transcriptional process is chromatin, a complex assembly of histones and DNA. Histones are subject to several post-translational modifications, like acetylation, that are a component of the transcriptional regulation process. Histone acetylation and deacetylation is performed by a group of enzymes (histone acetyltransferases (HATs) and deacetylases, respectively) whose modulation can alter the transcriptional state of many regions of the genome, and thus may be an important target in diseases that share this pathogenic process, as is the case for ALS. This review will discuss the present evidence of transcriptional dysregulation in ALS, the role of histone deacetylases (HDACs) in disease pathogenesis, and the novel pharmacologic strategies that are being comprehensively studied to prevent motor neuron death, with focus on sirtuins (SIRT) and their effectors. PMID:24367290

  15. Transcriptional analysis of histone deacetylase family members reveal similarities between differentiating and aging spermatogonial stem cells.

    PubMed

    Kofman, Amber E; Huszar, Jessica M; Payne, Christopher J

    2013-02-01

    The differentiation of adult stem cells involves extensive chromatin remodeling, mediated in part by the gene products of histone deacetylase (HDAC) family members. While the transcriptional downregulation of HDACs can impede stem cell self-renewal in certain contexts, it may also promote stem cell maintenance under other circumstances. In self-renewing, differentiating, and aging spermatogonial stem cells (SSCs), the gene expression dynamics of HDACs have not yet been characterized. To gain further insight with these studies, we analyzed the transcriptional profiles of six HDAC family members, previously identified to be the most highly expressed in self-renewing SSCs, during stem cell differentiation and aging. Here we discovered that in both differentiating and aging SSCs the expression of Sirt4 increases, while the expression of Hdac2, Hdac6, and Sirt1 decreases. When SSCs are exposed to the lifespan-enhancing drug rapamycin in vivo, the resultant HDAC gene expression patterns are opposite of those seen in the differentiating and aging SSCs, with increased Hdac2, Hdac6, and Sirt1 and decreased Hdac8, Hdac9, and Sirt4. Our findings suggest that HDACs important for stem cell maintenance and oxidative capacity are downregulated as adult stem cells differentiate or age. These results provide important insights into the epigenetic regulation of stem cell differentiation and aging in mammals.

  16. Complex structure of a bacterial class 2 histone deacetylase homologue with a trifluoromethylketone inhibitor

    SciTech Connect

    Nielsen, Tine Kragh; Hildmann, Christian; Riester, Daniel; Wegener, Dennis; Schwienhorst, Andreas; Ficner, Ralf

    2007-04-01

    The crystal structure of HDAH FB188 in complex with a trifluoromethylketone at 2.2 Å resolution is reported and compared to a previously determined inhibitor complex. Histone deacetylases (HDACs) have emerged as attractive targets in anticancer drug development. To date, a number of HDAC inhibitors have been developed and most of them are hydroxamic acid derivatives, typified by suberoylanilide hydroxamic acid (SAHA). Not surprisingly, structural information that can greatly enhance the design of novel HDAC inhibitors is so far only available for hydroxamic acids in complex with HDAC or HDAC-like enzymes. Here, the first structure of an enzyme complex with a nonhydroxamate HDAC inhibitor is presented. The structure of the trifluoromethyl ketone inhibitor 9,9,9-trifluoro-8-oxo-N-phenylnonanamide in complex with bacterial FB188 HDAH (histone deacetylase-like amidohydrolase from Bordetella/Alcaligenes strain FB188) has been determined. HDAH reveals high sequential and functional homology to human class 2 HDACs and a high structural homology to human class 1 HDACs. Comparison with the structure of HDAH in complex with SAHA reveals that the two inhibitors superimpose well. However, significant differences in binding to the active site of HDAH were observed. In the presented structure the O atom of the trifluoromethyl ketone moiety is within binding distance of the Zn atom of the enzyme and the F atoms participate in interactions with the enzyme, thereby involving more amino acids in enzyme–inhibitor binding.

  17. 3-Hydroxypyridin-2-thione as Novel Zinc Binding Group for Selective Histone Deacetylase Inhibition

    PubMed Central

    Patil, Vishal; Sodji, Quaovi H.; Kornacki, James R.; Mrksich, Milan; Oyelere, Adegboyega K.

    2013-01-01

    Small molecules bearing hydroxamic acid as the zinc binding group (ZBG) have been the most effective histone deacetylase inhibitor (HDACi) to date. However, concerns about the pharmacokinetic liabilities of the hydroxamic acid moiety have stimulated research efforts aimed at finding alternative non-hydroxamate ZBGs. We have identified 3-hydroxypyridin-2-thione (3-HPT) as a novel ZBG that is compatible with HDAC inhibition. 3-HPT inhibits HDAC 6 and HDAC 8 with an IC50 of 681 nM and 3675 nM respectively. Remarkably, 3-HPT gives no inhibition of HDAC 1. Subsequent optimization led to several novel 3HPT-based HDACi that are selective for HDAC 6 and HDAC 8. Furthermore, a subset of these inhibitors induces apoptosis in various cancer cell lines. PMID:23547652

  18. HISTONE DEACETYLASES AS TARGETS FOR THE TREATMENT OF HUMAN NEURODEGENERATIVE DISEASES

    PubMed Central

    D’Mello, Santosh R.

    2014-01-01

    SUMMARY Histone deacetylases (HDACs) are a family of proteins that play an important role in regulating transcription as well as the function of a variety of cellular proteins. While these proteins are expressed abundantly in the brain, little is known about their roles in brain function. A growing body of evidence suggests that HDACs regulate neuronal survival. Results from studies conducted in vertebrate and mammalian experimental systems indicate that while some of these proteins are involved in promoting neuronal death, a majority of the HDACs studied thus far protect against neurodegeneration. Here we review the research performed on the role played by individual members of the HDAC family in the regulation of neuronal death. Chemical inhibitors of HDACs have been used in a variety of models of neurodegenerative disorders. We summarize the results from these studies, which indicate that HDAC inhibitors show great promise as therapeutic agents for human neurodegenerative disorders. PMID:20072728

  19. 3-Hydroxypyridin-2-thione as novel zinc binding group for selective histone deacetylase inhibition.

    PubMed

    Patil, Vishal; Sodji, Quaovi H; Kornacki, James R; Mrksich, Milan; Oyelere, Adegboyega K

    2013-05-09

    Small molecules bearing hydroxamic acid as the zinc binding group (ZBG) have been the most effective histone deacetylase inhibitors (HDACi) to date. However, concerns about the pharmacokinetic liabilities of the hydroxamic acid moiety have stimulated research efforts aimed at finding alternative nonhydroxamate ZBGs. We have identified 3-hydroxypyridin-2-thione (3-HPT) as a novel ZBG that is compatible with HDAC inhibition. 3-HPT inhibits HDAC 6 and HDAC 8 with an IC50 of 681 and 3675 nM, respectively. Remarkably, 3-HPT gives no inhibition of HDAC 1. Subsequent optimization led to several novel 3HPT-based HDACi that are selective for HDAC 6 and HDAC 8. Furthermore, a subset of these inhibitors induces apoptosis in various cancer cell lines.

  20. Increased expression of histone deacetylases 2 in temporal lobe epilepsy: a study of epileptic patients and rat models.

    PubMed

    Huang, Yuanyuan; Zhao, Fenghua; Wang, Liang; Yin, Huan; Zhou, Chunlei; Wang, Xuefeng

    2012-02-01

    Histone deacetylases 2 (HDAC2) is expressed in the central nervous system; it has multiple functions in neural plasticity. However, we do not know if HDAC2 is also involved in the pathology of epilepsy. Here we report that HDAC2 was expressed in the brain tissues of both control and temporal lobe epilepsy (TLE) patients. Results from immunofluorescence and immunohistochemistry showed that HDAC2 was primarily located in the nucleus and that TLE patients exhibit significantly more HDAC2 positive cells than control. Western blotting showed that HDAC2 protein levels were significantly higher in TLE than in control brain. Moreover, in the rat model of TLE, there was a sustained enhancement of HDAC2 expression in rat models of TLE. HDAC2 was significantly increased in both the acute (1 day) and chronic (60 days) animals compared with control group. These results suggest that HDAC2 play an important role in the pathogenesis of human TLE.

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

    PubMed

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

    2014-08-01

    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.

  2. Phenotypic impact of deregulated expression of class I histone deacetylases in urothelial cell carcinoma of the bladder.

    PubMed

    Junqueira-Neto, Susana; Vieira, Filipa Q; Montezuma, Diana; Costa, Natália R; Antunes, Luís; Baptista, Tiago; Oliveira, Ana Isabel; Graça, Inês; Rodrigues, Ângelo; Magalhães, José S; Oliveira, Jorge; Henrique, Rui; Jerónimo, Carmen

    2015-07-01

    Deregulated expression of histone deacetylases (HDACs) has been implicated in tumorigenesis. Herein, we investigated class I HDACs expression in bladder urothelial cell carcinoma (BUCC), its prognostic value and biological significance. Significantly increased transcript levels of all HDACs were found in BUCC compared to 20 normal mucosas, and these were higher in lower grade and stage tumors. Increased HDAC3 levels were associated with improved patient survival. SiRNA experiments showed decrease cell viability and motility, and increased apoptosis. We concluded that class I HDACs play an important role in bladder carcinogenesis through deregulation of proliferation, migration and apoptosis, constituting putative therapeutic targets.

  3. Boric acid inhibits embryonic histone deacetylases: a suggested mechanism to explain boric acid-related teratogenicity.

    PubMed

    Di Renzo, Francesca; Cappelletti, Graziella; Broccia, Maria L; Giavini, Erminio; Menegola, Elena

    2007-04-15

    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.

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

    SciTech Connect

    Di Renzo, Francesca; Cappelletti, Graziella; Broccia, Maria L.; Giavini, Erminio; Menegola, Elena . E-mail: elena.menegola@unimi.it

    2007-04-15

    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.

  5. Overlapping and Divergent Actions of Structurally Distinct Histone Deacetylase Inhibitors in Cardiac Fibroblasts.

    PubMed

    Schuetze, Katherine B; Stratton, Matthew S; Blakeslee, Weston W; Wempe, Michael F; Wagner, Florence F; Holson, Edward B; Kuo, Yin-Ming; Andrews, Andrew J; Gilbert, Tonya M; Hooker, Jacob M; McKinsey, Timothy A

    2017-04-01

    Inhibitors of zinc-dependent histone deacetylases (HDACs) profoundly affect cellular function by altering gene expression via changes in nucleosomal histone tail acetylation. Historically, investigators have employed pan-HDAC inhibitors, such as the hydroxamate trichostatin A (TSA), which simultaneously targets members of each of the three zinc-dependent HDAC classes (classes I, II, and IV). More recently, class- and isoform-selective HDAC inhibitors have been developed, providing invaluable chemical biology probes for dissecting the roles of distinct HDACs in the control of various physiologic and pathophysiological processes. For example, the benzamide class I HDAC-selective inhibitor, MGCD0103 [N-(2-aminophenyl)-4-[[(4-pyridin-3-ylpyrimidin-2-yl)amino]methyl] benzamide], was shown to block cardiac fibrosis, a process involving excess extracellular matrix deposition, which often results in heart dysfunction. Here, we compare the mechanisms of action of structurally distinct HDAC inhibitors in isolated primary cardiac fibroblasts, which are the major extracellular matrix-producing cells of the heart. TSA, MGCD0103, and the cyclic peptide class I HDAC inhibitor, apicidin, exhibited a common ability to enhance histone acetylation, and all potently blocked cardiac fibroblast cell cycle progression. In contrast, MGCD0103, but not TSA or apicidin, paradoxically increased expression of a subset of fibrosis-associated genes. Using the cellular thermal shift assay, we provide evidence that the divergent effects of HDAC inhibitors on cardiac fibroblast gene expression relate to differential engagement of HDAC1- and HDAC2-containing complexes. These findings illustrate the importance of employing multiple compounds when pharmacologically assessing HDAC function in a cellular context and during HDAC inhibitor drug development.

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

    PubMed

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

    2013-09-01

    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.

  7. Emerging roles for histone deacetylases in age-related muscle atrophy

    PubMed Central

    Walsh, Michael E.; Van Remmen, Holly

    2016-01-01

    BACKGROUND: Skeletal muscle atrophy during aging, a process known as sarcopenia, is associated with muscle weakness, frailty, and the loss of independence in older adults. The mechanisms contributing to sarcopenia are not totally understood, but muscle fiber loss due to apoptosis, reduced stimulation of anabolic pathways, activation of catabolic pathways, denervation, and altered metabolism have been observed in muscle from old rodents and humans. OBJECTIVE: Recently, histone deacetylases (HDACs) have been implicated in muscle atrophy and dysfunction due to denervation, muscular dystrophy, and disuse, and HDACs play key roles in regulating metabolism in skeletal muscle. In this review, we will discuss the role of HDACs in muscle atrophy and the potential of HDAC inhibitors for the treatment of sarcopenia. CONCLUSIONS: Several HDAC isoforms are potential targets for intervention in sarcopenia. Inhibition of HDAC1 prevents muscle atrophy due to nutrient deprivation. HDAC3 regulates metabolism in skeletal muscle and may inhibit oxidative metabolism during aging. HDAC4 and HDAC5 have been implicated in muscle atrophy due to denervation, a process implicated in sarcopenia. HDAC inhibitors are already in use in the clinic, and there is promise in targeting HDACs for the treatment of sarcopenia. PMID:28035339

  8. Histone deacetylase 2 is phosphorylated, ubiquitinated, and degraded by cigarette smoke.

    PubMed

    Adenuga, David; Yao, Hongwei; March, Thomas H; Seagrave, Jeanclare; Rahman, Irfan

    2009-04-01

    Cigarette smoke (CS)-induced lung inflammation involves the reduction of histone deacetylase 2 (HDAC2) abundance, which is associated with steroid resistance in patients with chronic obstructive pulmonary disease and in individuals with severe asthma who smoke cigarettes. However, the molecular mechanism of CS-mediated reduction of HDAC2 is not clearly known. We hypothesized that HDAC2 is phosphorylated and subsequently degraded by the proteasome in vitro in macrophages (MonoMac6), human bronchial and primary small airway epithelial cells, and in vivo in mouse lungs in response to chronic CS exposure. Cigarette smoke extract (CSE) exposure in MonoMac6 and in bronchial and airway epithelial cells led to phosphorylation of HDAC2 on serine/threonine residues by a protein kinase CK2-mediated mechanism, decreased HDAC2 activity, and increased ubiquitin-proteasome-dependent HDAC2 degradation. CK2 and proteasome inhibitors reversed CSE-mediated HDAC2 degradation, whereas serine/threonine phosphatase inhibitor, okadaic acid, caused phosphorylation and subsequent ubiquitination of HDAC2. CS-induced HDAC2 phosphorylation was detected in mouse lungs from 2 weeks to 4 months of CS exposure, and mice showed significantly lower lung HDAC2 levels. Thus, CS-mediated down-regulation of HDAC2 in human macrophages and lung epithelial cells in vitro and in mouse lung in vivo involves the induction of serine/threonine phosphorylation and proteasomal degradation, which may have implications for steroid resistance and abnormal inflammation caused by cigarette smoke.

  9. Histone deacetylase enzyme silencing using shRNAs enhances radiosensitivity of SW579 thyroid cancer cells

    PubMed Central

    Wang, Ye; Jin, Tao; Dai, Xueming; Yan, Dongwang; Peng, Zhihai

    2016-01-01

    The aim of the present study was to screen the enzymes that are associated with the radiosensitivity of SW579 thyroid cancer cells, and investigate whether radiation, combined with specific RNA interference on the screened enzymes, enhances radiosensitivity of SW579 thyroid cancer cells. Quantitative polymerase chain reaction (qPCR) was used to analyze epigenetic enzyme expression changes before and after radiotherapy, and four enzymes, histone deacetylase 1 (HDAC1), HDAC2, HDAC4 and HDAC6 were screened. Western blot analysis was performed to analyze the change in HDAC1, HDAC2, HDAC4 and HDAC6 protein expression following radiotherapy. Short hairpin RNA (ShRNA)-HDAC1, shRNA-HDAC2, shRNA-HDAC4 and shRNA-HDAC6 plasmids were constructed and SW579 cells were transfected with corresponding shRNA-HDACs. Reverse transcription-qPCR was used to detect whether downregulation of HDAC mRNAs had been effective. In addition, shRNA and shRNA negative control (NC) pools were established and transfected into the SW579 cells. The samples were divided into four groups; control, trichostatin A, shRNA pool and shRNA NC pool, to analyze the effective enhancement of specific shRNA on radiosensitivity in thyroid cancer cells. The morphological changes were observed in the SW579 cells, and the number of tumor cells decreased markedly in the shRNA pool group compared with that of the other three groups. Therefore, it was concluded that HDACs present a potential target for increasing the sensitivity of thyroid cancer cells to radiotherapy, and shRNA-HDAC interference combined with radiotherapy promotes the radiosensitivity of tumors. PMID:27600599

  10. Inhibiting histone deacetylases suppresses glucose metabolism and hepatocellular carcinoma growth by restoring FBP1 expression

    PubMed Central

    Yang, Jing; Jin, Xin; Yan, Yuqian; Shao, Yingjie; Pan, Yunqian; Roberts, Lewis R.; Zhang, Jun; Huang, Haojie; Jiang, Jingting

    2017-01-01

    Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers in the world. Elevated glucose metabolism in the availability of oxygen, a phenomenon called the Warburg effect, is important for cancer cell growth. Fructose-1,6-bisphosphatase (FBP1) is a rate-limiting enzyme in gluconeogenesis and is frequently lost in various types of cancer. Here, we demonstrated that expression of FBP1 was downregulated in HCC patient specimens and decreased expression of FBP1 associated with poor prognosis. Low expression of FBP1 correlated with high levels of histone deacetylase 1 (HDAC1) and HDAC2 proteins in HCC patient tissues. Treatment of HCC cells with HDAC inhibitors or knockdown of HDAC1 and/or HDAC2 restored FBP1 expression and inhibited HCC cell growth. HDAC-mediated suppression of FBP1 expression correlated with decreased histone H3 lysine 27 acetylation (H3K27Ac) in the FBP1 enhancer. Restored expression of FBP1 decreased glucose reduction and lactate secretion and inhibited HCC cell growth in vitro and tumor growth in mice. Our data reveal that loss of FBP1 due to histone deacetylation associates with poor prognosis of HCC and restored FBP1 expression by HDAC inhibitors suppresses HCC growth. Our findings suggest that repression of FBP1 by HDACs has important implications for HCC prognosis and treatment. PMID:28262837

  11. Anti-Inflammatory Effects of Spirulina platensis Extract via the Modulation of Histone Deacetylases.

    PubMed

    Pham, Tho X; Park, Young-Ki; Lee, Ji-Young

    2016-06-21

    We previously demonstrated that the organic extract of Spirulina platensis (SPE), an edible blue-green alga, possesses potent anti-inflammatory effects. In this study, we investigated if the regulation of histone deacetylases (HDACs) play a role in the anti-inflammatory effect of SPE in macrophages. Treatment of macrophages with SPE rapidly and dose-dependently reduced HDAC2, 3, and 4 proteins which preceded decreases in their mRNA levels. Degradation of HDAC4 protein was attenuated in the presence of inhibitors of calpain proteases, lysosomal acidification, and Ca(2+)/calmodulin-dependent protein kinase II, respectively, but not a proteasome inhibitor. Acetylated histone H3 was increased in SPE-treated macrophages to a similar level as macrophages treated with a pan-HDAC inhibitor, with concomitant inhibition of inflammatory gene expression upon LPS stimulation. Knockdown of HDAC3 increased basal and LPS-induced pro-inflammatory gene expression, while HDAC4 knockdown increased basal expression of interleukin-1β (IL-1β), but attenuated LPS-induced inflammatory gene expression. Chromatin immunoprecipitation showed that SPE decreased p65 binding and H3K9/K14 acetylation at the Il-1β and tumor necrosis factor α (Tnfα) promoters. Our results suggest that SPE increased global histone H3 acetylation by facilitating HDAC protein degradation, but decreases histone H3K9/K14 acetylation and p65 binding at the promoters of Il-1β and Tnfα to exert its anti-inflammatory effect.

  12. Is There a Link Between Expression Levels of Histone Deacetylase/Acetyltransferase in Mouse Sperm and Subsequent Blastocyst Development?

    PubMed

    Kim, Jayeon; Kim, Ji-Hee; Jee, Byung-Chul; Suh, Chang-Suk; Kim, Seok-Hyun

    2015-11-01

    Histone acetylation has been known to be significant in spermatogenesis. Histone acetylation is regulated by the act of histone deacetylases (HDACs) and histone acetyltransferases (HATs). We investigated the link between expression levels of HDACs and HATs in mouse sperm and subsequent blastocyst formation rate. In the univariate analysis, expression levels of HDAC1 and HAT were generally not associated with the blastocyst formation rate. When divided by the mature oocyte number category, a significant positive association was observed between the expression levels of HDAC1 and the blastocyst-forming rate in the highest (> 75th) percentile group (a group with ≥34 mature oocytes). In conclusion, expression of sperm HDAC1 could be considered as a possible predictor of embryo development in mice with high ovarian response.

  13. Histone deacetylase inhibitors relieve morphine resistance in neuropathic pain after peripheral nerve injury.

    PubMed

    Uchida, Hitoshi; Matsushita, Yosuke; Araki, Kohei; Mukae, Takehiro; Ueda, Hiroshi

    2015-08-01

    Neuropathic pain is often insensitive to morphine. Our previous study has demonstrated that neuron-restrictive silencer factor represses mu opioid receptor (MOP) gene expression in the dorsal root ganglion (DRG) via histone hypoacetylation-mediated mechanisms after peripheral nerve injury, thereby causing loss of peripheral morphine analgesia. Here, we showed that histone deacetylase (HDAC) inhibitors, such as trichostatin A and valproic acid, restored peripheral and systemic morphine analgesia in neuropathic pain. Also, these agents blocked nerve injury-induced MOP down-regulation in the DRG. These results suggest that HDAC inhibitors could serve as adjuvant analgesics to morphine for the management of neuropathic pain.

  14. Discovery of a new class of histone deacetylase inhibitors with a novel zinc binding group

    PubMed Central

    Li, Youxuan; Woster, Patrick M.

    2015-01-01

    Small molecules featuring a hydroxamic acid or a benzamide zinc binding group (ZBG) are the most thoroughly studied histone deacetylase (HDAC) inhibitors. However, concerns about the pharmacokinetic liabilities of the hydroxamic acid moiety and potential metabolic toxicity of the aniline portion of benzamide HDAC inhibitors have stimulated research efforts aimed at discovering alternative ZBGs. Here we report the 2-(oxazol-2-yl)phenol moiety as a novel ZBG that can be used to produce compounds that are potent HDAC inhibitors. A series of analogues with this novel ZBG have been synthesized, and these analogues exhibit selective inhibition against HDAC1 as well as the class IIb HDACs (HDAC6 and HDAC10). Compound 10 possesses an IC50 value of 7.5 μM in the MV-4-11 leukemia cell line, and induces a comparable amount of acetylated histone 3 lysine 9 (H3K9) and p21Waf1/CIP1 as 0.5 μM of SAHA. Modeling of compound 10 in the active site of HDAC2 demonstrates that the 2-(oxazol-2-yl)phenol moiety has a zinc-binding pattern similar to benzamide HDAC inhibitors. PMID:26005563

  15. Unraveling Site-Specific and Combinatorial Histone Modifications Using High-Resolution Mass Spectrometry in Histone Deacetylase Mutants of Fission Yeast.

    PubMed

    Abshiru, Nebiyu; Rajan, Roshan Elizabeth; Verreault, Alain; Thibault, Pierre

    2016-07-01

    Histone deacetylases (HDACs) catalyze the removal of acetylation marks from lysine residues on histone and nonhistone substrates. Their activity is generally associated with essential cellular processes such as transcriptional repression and heterochromatin formation. Interestingly, abnormal activity of HDACs has been reported in various types of cancers, which makes them a promising therapeutic target for cancer treatment. In the current study, we aim to understand the mechanisms underlying the function of HDACs using an in-depth quantitative analysis of changes in histone acetylation levels in Schizosaccharomyces pombe (S. pombe) lacking major HDAC activities. We employed a targeted quantitative mass spectrometry approach to profile changes of acetylation and methylation at multiple lysine residues on the N-terminal tail of histones H3 and H4. Our analyses identified a number of histone acetylation sites that are significantly affected by S. pombe HDAC mutations. We discovered that mutation of the Class I HDAC known as Clr6 causes a major increase in the abundance of triacetylated H4 molecules at K5, K8, and K12. A clr6-1 hypomorphic mutation also increased the abundance of multiple acetyl-lysines in histone H3. In addition, our study uncovered a few crosstalks between histone acetylation and methylation upon deletion of HDACs Hos2 and Clr3. We anticipate that the results from this study will greatly improve our current understanding of the mechanisms involved in HDAC-mediated gene regulation and heterochromatin assembly.

  16. Single-Molecule Electronic Measurements of the Dynamic Flexibility of Histone Deacetylases

    NASA Astrophysics Data System (ADS)

    Froberg, James; You, Seungyong; Yu, Junru; Haldar, Manas; Sedigh, Abbas; Mallik, Sanku; Srivastava, D. K.; Choi, Yongki

    Due to their involvement in epigenetic regulation, histone deacetylases (HDACs) have gained considerable interest in designing drugs for treatment of a variety of human diseases including cancers. Recently, we applied a label-free, electronic single-molecule nano-circuit technique to gain insight into the contribution of the dynamic flexibility in HDACs structure during the course of substrates/ ligands binding and catalysis. We observed that HDAC8 has two major (dynamically interconvertible) conformational states, ``ground (catalytically unfavorable)'' and ``transition (catalytically favorable)''. In addition, we found that its cognate substrates/ligands reciprocally catalyze the transition of the ground to the transition state conformation of HDAC8. Thus, we propose that both enzymes and their substrates/ligands serve as ``catalysts'' in facilitating the structural changes of each other and promoting the overall chemical transformation reaction. Such new information provides the potential for designing a new class of mechanism-based inhibitors and activators of HDAC8 for treating human diseases.

  17. Silencing of Histone Deacetylase 9 Expression in Podocytes Attenuates Kidney Injury in Diabetic Nephropathy

    PubMed Central

    Liu, Feng; Zong, Ming; Wen, Xiaofei; Li, Xuezhu; Wang, Jun; Wang, Yi; Jiang, Wei; Li, Xiaojun; Guo, Zhongliang; Qi, Hualin

    2016-01-01

    Podocyte dysfunction is important in the onset and development of diabetic nephropathy (DN). Histone deacetylases (HDACs) have been recently proved to play critical roles in the pathogenesis of DN. As one subtype of the class IIa HDACs, HDAC9 is capable to repress/de-repress their target genes in tumor, inflammation, atherosclerosis and metabolic diseases. In the present study, we investigate whether HDAC9 is involved in the pathophysiologic process of DN, especially the podocyte injury. Firstly, we explored the expression patterns and localization of HDAC9 and found that HDAC9 expression was significantly up-regulated in high glucose (HG)-treated mouse podocytes, as well as kidney tissues from diabetic db/db mice and patients with DN. Secondly, knockdown of HDAC9 in mouse podocytes significantly suppressed HG-induced reactive oxygen species (ROS) generation, cell apoptosis and inflammation through JAK2/STAT3 pathway and reduced the podocytes injury by decreasing the expression levels of Nephrin and Podocin. Moreover, in diabetic db/db mice, silencing of HDAC9 attenuated the glomerulosclerosis, inflammatory cytokine release, podocyte apoptosis and renal injury. Collectively, these data indicate that HDAC9 may be involved in the process of DN, especially podocyte injury. Our study suggest that inhibition of HDAC9 may have a therapeutic potential in DN treatment. PMID:27633396

  18. Histone deacetylase 3 associates with MeCP2 to regulate FOXO and social behavior

    PubMed Central

    Nott, Alexi; Cheng, Jemmie; Gao, Fan; Lin, Yuan-Ta; Gjoneska, Elizabeta; Ko, Tak; Minhas, Paras; Zamudio, Alicia Viridiana; Meng, Jia; Zhang, Feiran; Jin, Peng; Tsai, Li-Huei

    2016-01-01

    Mutations in MECP2 cause the neurodevelopmental disorder Rett syndrome (RTT). The RTT missense MECP2R306C mutation prevents MeCP2 interaction with NCoR/Histone deacetylase 3 (HDAC3); however, the neuronal function of HDAC3 is incompletely understood. We report that neuronal deletion of Hdac3 in mice elicits abnormal locomotor coordination, sociability, and cognition. Transcriptional and chromatin profiling revealed HDAC3 positively regulates a subset of genes and is recruited to active gene promoters via MeCP2. HDAC3-associated promoters are enriched for the FOXO transcription factors, and FOXO acetylation is elevated in Hdac3 KO and Mecp2 KO neurons. Human RTT patient-derived MECP2R306C neural progenitor cells have deficits in HDAC3 and FOXO recruitment and gene expression. Gene editing of MECP2R306C cells to generate isogenic controls rescued HDAC3-FOXO-mediated impairments in gene expression. Our data suggests that HDAC3 interaction with MeCP2 positively regulates a subset of neuronal genes through FOXO deacetylation, and disruption of HDAC3 contributes to cognitive and social impairment. PMID:27428650

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

    PubMed Central

    Casper, Michelle E.; McGee-Lawrence, Meghan E.; Stensgard, Bridget A.; Li, Xiaodong; Secreto, Frank J.; Knutson, Sarah K.; Hiebert, Scott W.; Westendorf, Jennifer J.

    2010-01-01

    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 had severe deficits in intramembranous and endochondral bone formation. Calvarial bones were significantly thinner and trabecular bone volume in the distal femur was decreased 75% in the Hdac3 CKO mice due to a substantial reduction in trabecular number. Hdac3-CKO mice had fewer osteoblasts and more bone marrow adipocytes as a proportion of tissue area than their wildtype or heterozygous littermates. Bone formation rates were depressed in both the cortical and trabecular regions of Hdac3 CKO femurs. Microarray analyses revealed that numerous developmental signaling pathways were affected by Hdac3-deficiency. Thus, Hdac3 depletion in osterix-expressing progenitor cells interferes with bone formation and promotes bone marrow adipocyte differentiation. These results demonstrate that Hdac3 inhibition is detrimental to skeletal health. PMID:20628553

  20. Histone deacetylase 6 associates with ribosomes and regulates de novo protein translation during arsenite stress.

    PubMed

    Kappeler, Kyle V; Zhang, Jack; Dinh, Thai Nho; Strom, Joshua G; Chen, Qin M

    2012-05-01

    Histone deacetylase 6 (HDAC6) is known as a cytoplasmic enzyme that regulates cell migration, cell adhesion, and degradation of misfolded proteins by deacetylating substrates such as α-tubulin and Hsp90. When HaCaT keratinocytes were exposed to 1-200μM sodium arsenite, we observed perinuclear localization of HDAC6 within 30 min. Although the overall level of HDAC6 protein did not change, sodium arsenite caused an increase of HDAC6 in ribosomal fractions. Separation of ribosomal subunits versus intact ribosomes or polysomes indicated that HDAC6 was mainly detected in 40/43S fractions containing the small ribosomal subunit in untreated cells but was associated with 40/43S and 60/80S ribosomal fractions in arsenite-treated cells. Immunocytochemistry studies revealed that arsenite caused colocalization of HDAC6 with the ribosomal large and small subunit protein L36a and S6. Both L36a and S6 were detected in the immunocomplex of HDAC6 isolated from arsenite-treated cells. The observed physical interaction of HDAC6 with ribosomes pointed to a role of HDAC6 in stress-induced protein translation. Among arsenite stress-induced proteins, de novo Nrf2 protein translation was inhibited by Tubastatin A. These data demonstrate that HDAC6 was recruited to ribosomes, physically interacted with ribosomal proteins, and regulated de novo protein translation in keratinocytes responding to arsenite stress.

  1. A Limited Group of Class I Histone Deacetylases Acts To Repress Human Immunodeficiency Virus Type 1 Expression▿

    PubMed Central

    Keedy, Kara S.; Archin, Nancie M.; Gates, Adam T.; Espeseth, Amy; Hazuda, Daria J.; Margolis, David M.

    2009-01-01

    Silencing of the integrated human immunodeficiency virus type 1 (HIV-1) genome in resting CD4+ T cells is a significant contributor to the persistence of infection, allowing the virus to evade both immune detection and pharmaceutical attack. Nonselective histone deacetylase (HDAC) inhibitors are capable of inducing expression of quiescent HIV-1 in latently infected cells. However, potent global HDAC inhibition can induce host toxicity. To determine the specific HDACs that regulate HIV-1 transcription, we evaluated HDAC1 to HDAC11 RNA expression and protein expression and compartmentalization in the resting CD4+ T cells of HIV-1-positive, aviremic patients. HDAC1, -3, and -7 had the highest mRNA expression levels in these cells. Although all HDACs were detected in resting CD4+ T cells by Western blot analysis, HDAC5, -8, and -11 were primarily sequestered in the cytoplasm. Using chromatin immunoprecipitation assays, we detected HDAC1, -2, and -3 at the HIV-1 promoter in Jurkat J89GFP cells. Targeted inhibition of HDACs by small interfering RNA demonstrated that HDAC2 and HDAC3 contribute to repression of HIV-1 long terminal repeat expression in the HeLa P4/R5 cell line model of latency. Together, these results suggest that HDAC inhibitors specific for a limited number of class I HDACs may offer a targeted approach to the disruption of persistent HIV-1 infection. PMID:19279091

  2. Histone deacetylases: Targets for antifungal drug development

    PubMed Central

    Kmetzsch, Livia

    2015-01-01

    The interaction of pathogens and its hosts causes a drastic change in the transcriptional landscape in both cells. Among the several mechanisms of gene regulation, transcriptional initiation is probably the main point. In such scenario, the access of transcriptional machinery to promoter is highly regulated by post-translational modification of histones, such as acetylation, phosphorylation and others. Inhibition of histone deacetylases is able to reduce fungal pathogens fitness during infection and, therefore, is currently being considered for the development of new antifungal therapy strategies. PMID:26151486

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

    SciTech Connect

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

    2012-09-15

    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.

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

    SciTech Connect

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

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: 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.

  5. Histone deacetylases 1 and 2 regulate autophagy flux and skeletal muscle homeostasis in mice

    PubMed Central

    Moresi, Viviana; Carrer, Michele; Grueter, Chad E.; Rifki, Oktay F.; Shelton, John M.; Richardson, James A.; Bassel-Duby, Rhonda; Olson, Eric N.

    2012-01-01

    Maintenance of skeletal muscle structure and function requires efficient and precise metabolic control. Autophagy plays a key role in metabolic homeostasis of diverse tissues by recycling cellular constituents, particularly under conditions of caloric restriction, thereby normalizing cellular metabolism. Here we show that histone deacetylases (HDACs) 1 and 2 control skeletal muscle homeostasis and autophagy flux in mice. Skeletal muscle-specific deletion of both HDAC1 and HDAC2 results in perinatal lethality of a subset of mice, accompanied by mitochondrial abnormalities and sarcomere degeneration. Mutant mice that survive the first day of life develop a progressive myopathy characterized by muscle degeneration and regeneration, and abnormal metabolism resulting from a blockade to autophagy. HDAC1 and HDAC2 regulate skeletal muscle autophagy by mediating the induction of autophagic gene expression and the formation of autophagosomes, such that myofibers of mice lacking these HDACs accumulate toxic autophagic intermediates. Strikingly, feeding HDAC1/2 mutant mice a high-fat diet from the weaning age releases the block in autophagy and prevents myopathy in adult mice. These findings reveal an unprecedented and essential role for HDAC1 and HDAC2 in maintenance of skeletal muscle structure and function and show that, at least in some pathological conditions, myopathy may be mitigated by dietary modifications. PMID:22307625

  6. Histone deacetylase 5 promotes Wilms' tumor cell proliferation through the upregulation of c-Met.

    PubMed

    Cao, Xu; Liu, De-Hong; Zhou, Yun; Yan, Xiang-Ming; Yuan, Li-Qun; Pan, Jian; Fu, Ming-Cui; Zhang, Ting; Wang, Jian

    2016-03-01

    The histone deacetylase (HDAC) family is comprised of enzymes, which are involved in modulating the majority of critical cellular processes, including transcriptional regulation, apoptosis, proliferation and cell cycle progression. However, the biological function of HDAC5 in Wilms' tumor remains to be fully elucidated. The present study aimed to investigate the expression and function of HDAC5 in Wilm's tumor. It was demonstrated that the mRNA and protein levels of HDAC5 were upregulated in human Wilms' tumor tissues. Overexpression of HDAC5 in G401 cells was observed to significantly promote cellular proliferation, as demonstrated by the results of an MTT assay and bromodeoxyuridine incorporation assay. By contrast, HDAC5 knockdown using small interfering RNA suppressed the proliferation of the G401 cells. At the molecular level, the present study demonstrated that HDAC5 promoted the expression of c‑Met, which has been previously identified as an oncogene. In addition, downregulation of c‑Met inhibited the proliferative effects of HDAC5 in human Wilms' tumor cells. Taken together, these results suggested that HDAC5 promotes cellular proliferation through the upregulation of c‑Met, and may provide a novel therapeutic target for the treatment of patients with Wilms' tumor.

  7. Histone Deacetylase 3 Coordinates Deacetylase-independent Epigenetic Silencing of Transforming Growth Factor-β1 (TGF-β1) to Orchestrate Second Heart Field Development*

    PubMed Central

    Lewandowski, Sara L.; Janardhan, Harish P.; Trivedi, Chinmay M.

    2015-01-01

    About two-thirds of human congenital heart disease involves second heart field-derived structures. Histone-modifying enzymes, histone deacetylases (HDACs), regulate the epigenome; however, their functions within the second heart field remain elusive. Here we demonstrate that histone deacetylase 3 (HDAC3) orchestrates epigenetic silencing of Tgf-β1, a causative factor in congenital heart disease pathogenesis, in a deacetylase-independent manner to regulate development of second heart field-derived structures. In murine embryos lacking HDAC3 in the second heart field, increased TGF-β1 bioavailability is associated with ascending aortic dilatation, outflow tract malrotation, overriding aorta, double outlet right ventricle, aberrant semilunar valve development, bicuspid aortic valve, ventricular septal defects, and embryonic lethality. Activation of TGF-β signaling causes aberrant endothelial-to-mesenchymal transition and altered extracellular matrix homeostasis in HDAC3-null outflow tracts and semilunar valves, and pharmacological inhibition of TGF-β rescues these defects. HDAC3 recruits components of the PRC2 complex, methyltransferase EZH2, EED, and SUZ12, to the NCOR complex to enrich trimethylation of Lys-27 on histone H3 at the Tgf-β1 regulatory region and thereby maintains epigenetic silencing of Tgf-β1 specifically within the second heart field-derived mesenchyme. Wild-type HDAC3 or catalytically inactive HDAC3 expression rescues aberrant endothelial-to-mesenchymal transition and epigenetic silencing of Tgf-β1 in HDAC3-null outflow tracts and semilunar valves. These findings reveal that epigenetic dysregulation within the second heart field is a predisposing factor for congenital heart disease. PMID:26420484

  8. Histone Deacetylase 3 Coordinates Deacetylase-independent Epigenetic Silencing of Transforming Growth Factor-β1 (TGF-β1) to Orchestrate Second Heart Field Development.

    PubMed

    Lewandowski, Sara L; Janardhan, Harish P; Trivedi, Chinmay M

    2015-11-06

    About two-thirds of human congenital heart disease involves second heart field-derived structures. Histone-modifying enzymes, histone deacetylases (HDACs), regulate the epigenome; however, their functions within the second heart field remain elusive. Here we demonstrate that histone deacetylase 3 (HDAC3) orchestrates epigenetic silencing of Tgf-β1, a causative factor in congenital heart disease pathogenesis, in a deacetylase-independent manner to regulate development of second heart field-derived structures. In murine embryos lacking HDAC3 in the second heart field, increased TGF-β1 bioavailability is associated with ascending aortic dilatation, outflow tract malrotation, overriding aorta, double outlet right ventricle, aberrant semilunar valve development, bicuspid aortic valve, ventricular septal defects, and embryonic lethality. Activation of TGF-β signaling causes aberrant endothelial-to-mesenchymal transition and altered extracellular matrix homeostasis in HDAC3-null outflow tracts and semilunar valves, and pharmacological inhibition of TGF-β rescues these defects. HDAC3 recruits components of the PRC2 complex, methyltransferase EZH2, EED, and SUZ12, to the NCOR complex to enrich trimethylation of Lys-27 on histone H3 at the Tgf-β1 regulatory region and thereby maintains epigenetic silencing of Tgf-β1 specifically within the second heart field-derived mesenchyme. Wild-type HDAC3 or catalytically inactive HDAC3 expression rescues aberrant endothelial-to-mesenchymal transition and epigenetic silencing of Tgf-β1 in HDAC3-null outflow tracts and semilunar valves. These findings reveal that epigenetic dysregulation within the second heart field is a predisposing factor for congenital heart disease.

  9. In Vitro Targeting Reveals Intrinsic Histone Tail Specificity of the Sin3/Histone Deacetylase and N-CoR/SMRT Corepressor Complexes

    PubMed Central

    Vermeulen, Michiel; Carrozza, Michael J.; Lasonder, Edwin; Workman, Jerry L.; Logie, Colin; Stunnenberg, Hendrik G.

    2004-01-01

    The histone code is among others established via differential acetylation catalyzed by histone acetyltransferases (HATs) and histone deacetylases (HDACs). To unambiguously determine the histone tail specificity of HDAC-containing complexes, we have established an in vitro system consisting of nucleosomal templates reconstituted with hyperacetylated histones or recombinant histones followed by acetylation with native SAGA or NuA4. Selective targeting of the mammalian Sin3/HDAC and N-CoR/SMRT corepressor complexes by using specific chimeric repressors created a near physiological setting to assess their histone tail specificity. Recruitment of the Sin3/HDAC complex to nucleosomal templates preacetylated with SAGA or NuA4 resulted in deacetylation of histones H3 and H4, whereas recruitment of N-CoR/SMRT resulted in deacetylation of histone H3 only. These results provide solid evidence that HDAC-containing complexes display distinct, intrinsic histone tail specificities and hence may function differently to regulate chromatin structure and transcription. PMID:14993276

  10. Histone deacetylase inhibition and the regulation of cell growth with particular reference to liver pathobiology.

    PubMed

    Joanna, Fraczek; van Grunsven, Leo A; Mathieu, Vinken; Sarah, Snykers; Sarah, Deleu; Karin, Vanderkerken; Tamara, Vanhaecke; Vera, Rogiers

    2009-09-01

    The transcriptional activity of genes largely depends on the accessibility of specific chromatin regions to transcriptional regulators. This process is controlled by diverse post-transcriptional modifications of the histone amino termini of which reversible acetylation plays a vital role. Histone acetyltransferases (HATs) are responsible for the addition of acetyl groups and histone deacetylases (HDACs) catalyse the reverse reaction. In general, though not exclusively, histone acetylation is associated with a positive regulation of transcription, whereas histone deacetylation is correlated with transcriptional silencing. The elucidation of unequivocal links between aberrant action of HDACs and tumorigenesis lies at the base of key scientific importance of these enzymes. In particular, the potential benefit of HDAC inhibition has been confirmed in various tumour cell lines, demonstrating antiproliferative, differentiating and pro-apoptotic effects. Consequently, the dynamic quest for HDAC inhibitors (HDIs) as a new class of anticancer drugs was set off, resulting in a number of compounds that are currently evaluated in clinical trials. Ironically, the knowledge with respect to the expression pattern and function of individual HDAC isoenzymes remains largely elusive. In the present review, we provide an update of the current knowledge on the involvement of HDACs in the regulation of fundamental cellular processes in the liver, being the main site for drug metabolism within the body. Focus lies on the involvement of HDACs in the regulation of growth of normal and transformed hepatocytes and the transdifferentiation process of stellate cells. Furthermore, extrapolation of our present knowledge on HDAC functionality towards innovative treatment of malignant and non-malignant, hyperproliferative and inflammatory disorders is discussed.

  11. Histone Deacetylase Inhibitor Trichostatin a Promotes the Apoptosis of Osteosarcoma Cells through p53 Signaling Pathway Activation

    PubMed Central

    Deng, Zhantao; Liu, Xiaozhou; Jin, Jiewen; Xu, Haidong; Gao, Qian; Wang, Yong; Zhao, Jianning

    2016-01-01

    Purpose: The purpose of this study was to investigate the profile of histone deacetylase (HDAC) activity and expression in osteosarcoma cells and tissues from osteosarcoma patients and to examine the mechanism by which a histone deacetylase (HDAC) inhibitor, Trichostatin A (TSA), promotes the apoptosis of osteosarcoma cells. Methods: HDAC activity and histone acetyltransferase (HAT) activity were determined in nuclear extracts of MG63 cells, hFOB 1.19 cells and tissues from 6 patients with primary osteosarcoma. The protein expression of Class I HDACs (1, 2, 3 and 8) and the activation of the p53 signaling pathway were examined by Western blot. Cell growth and apoptosis were determined by 3-(4, 5-dimethyl-2-thiazolyl)-2H-tetrazolium bromide (MTT) assay and flow cytometry, respectively. Results: Nuclear HDAC activity and class I HDAC expression were significantly higher in MG63 cells than in hFOB 1.19 cells, and a similar trend was observed in the human osteosarcoma tissues compared with the paired adjacent non-cancerous tissues. TSA significantly inhibited the growth of MG63 cells and promoted apoptosis in a dose-dependent manner through p53 signaling pathway activation. Conclusion: Class I HDACs play a central role in the pathogenesis of osteosarcoma, and HDAC inhibitors may thus have promise as new therapeutic agents against osteosarcoma. PMID:27877082

  12. Inhibitors of Histone Deacetylases for Radiosensitization of Prostate Cancer

    DTIC Science & Technology

    2005-02-01

    AD Award Number: W81XWH-04-1-0170 TITLE: Inhibitors of Histone Deacetylases for Radiosensitization of Prostate Cancer PRINCIPAL INVESTIGATOR: Mira 0...of Histone Deacetylases for Radiosensitization W81XWH-04-1-0170 of Prostate Cancer 6. AUTHOR(S) Mira 0. Jung, Ph.D. 7. PERFORMING ORGANIZA TION NAME(S...cellular radiation sensitivity. 14. SUBJECT TERMS 15. NUMBER OF PA GES Radiation sensitivity, histone deacetylase , cytotoxicity 13 16. PRICE CODE 17

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

    PubMed

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

    2014-09-01

    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.

  14. Nitric oxide modulates chromatin folding in human endothelial cells via protein phosphatase 2A activation and class II histone deacetylases nuclear shuttling.

    PubMed

    Illi, Barbara; Dello Russo, Claudio; Colussi, Claudia; Rosati, Jessica; Pallaoro, Michele; Spallotta, Francesco; Rotili, Dante; Valente, Sergio; Ragone, Gianluca; Martelli, Fabio; Biglioli, Paolo; Steinkuhler, Christian; Gallinari, Paola; Mai, Antonello; Capogrossi, Maurizio C; Gaetano, Carlo

    2008-01-04

    Nitric oxide (NO) modulates important endothelial cell (EC) functions and gene expression by a molecular mechanism which is still poorly characterized. Here we show that in human umbilical vein ECs (HUVECs) NO inhibited serum-induced histone acetylation and enhanced histone deacetylase (HDAC) activity. By immunofluorescence and Western blot analyses it was found that NO induced class II HDAC4 and 5 nuclear shuttling and that class II HDACs selective inhibitor MC1568 rescued serum-dependent histone acetylation above control level in NO-treated HUVECs. In contrast, class I HDACs inhibitor MS27-275 had no effect, indicating a specific role for class II HDACs in NO-dependent histone deacetylation. In addition, it was found that NO ability to induce HDAC4 and HDAC5 nuclear shuttling involved the activation of the protein phosphatase 2A (PP2A). In fact, HDAC4 nuclear translocation was impaired in ECs expressing small-t antigen and exposed to NO. Finally, in cells engineered to express a HDAC4-Flag fusion protein, NO induced the formation of a macromolecular complex including HDAC4, HDAC3, HDAC5, and an active PP2A. The present results show that NO-dependent PP2A activation plays a key role in class II HDACs nuclear translocation.

  15. Mitotic Activation of a Novel Histone Deacetylase 3-Linker Histone H1.3 Protein Complex by Protein Kinase CK2.

    PubMed

    Patil, Hemangi; Wilks, Carrie; Gonzalez, Rhiannon W; Dhanireddy, Sudheer; Conrad-Webb, Heather; Bergel, Michael

    2016-02-12

    Histone deacetylase 3 (HDAC3) and linker histone H1 are involved in both chromatin compaction and the regulation of mitotic progression. However, the mechanisms by which HDAC3 and H1 regulate mitosis and the factors controlling HDAC3 and H1 activity during mitosis are unclear. Furthermore, as of now, no association between class I, II, or IV (non-sirtuin) HDACs and linker histones has been reported. Here we describe a novel HDAC3-H1.3 complex containing silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) and nuclear receptor corepressor 1 (N-CoR) that accumulated in synchronized HeLa cells in late G2 phase and mitosis. Nonetheless, the deacetylation activity by HDAC3 in the complex was evident only in mitotic complexes. HDAC3 associated with H1.3 was highly phosphorylated on Ser-424 only during mitosis. Isolation of inactive HDAC3-H1.3 complexes from late G2 phase cells, and phosphorylation of HDAC3 in the complexes at serine 424 by protein kinase CK2 (also known as casein kinase 2) activated the HDAC3 in vitro. In vivo, CK2α and CK2α' double knockdown cells demonstrated a significant decrease in HDAC3 Ser-424 phosphorylation during mitosis. HDAC3 and H1.3 co-localized in between the chromosomes, with polar microtubules and spindle poles during metaphase through telophase, and partially co-localized with chromatin during prophase and interphase. H1 has been reported previously to associate with microtubules and, therefore, could potentially function in targeting HDAC3 to the microtubules. We suggest that phosphorylation of HDAC3 in the complex by CK2 during mitosis activates the complex for a dual role: compaction of the mitotic chromatin and regulation of polar microtubules dynamic instability.

  16. Thermodynamics of ligand binding to histone deacetylase like amidohydrolase from Bordetella/Alcaligenes.

    PubMed

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

    2014-03-01

    Thermodynamic studies on ligand-protein binding have become increasingly important in the process of drug design. In combination with structural data and molecular dynamics simulations, thermodynamic studies provide relevant information about the mode of interaction between compounds and their target proteins and therefore build a sound basis for further drug optimization. Using the example of histone deacetylases (HDACs), particularly the histone deacetylase like amidohydrolase (HDAH) from Bordetella/Alcaligenes, a novel sensitive competitive fluorescence resonance energy transfer-based binding assay was developed and the thermodynamics of interaction of both fluorescent ligands and inhibitors to histone deacetylase like amidohydrolase were investigated. The assay consumes only small amounts of valuable target proteins and is suitable for fast kinetic and mechanistic studies as well as high throughput screening applications. Binding affinity increased with increasing length of aliphatic spacers (n = 4-7) between the hydroxamate moiety and the dansyl head group of ligand probes. Van't Hoff plots revealed an optimum in enthalpy contribution to the free energy of binding for the dansyl-ligand with hexyl spacer. The selectivity in the series of dansyl-ligands against human class I HDAC1 but not class II HDACs 4 and 6 increased with the ratio of ΔH(0)/ΔG(0). The data clearly emphasize the importance of thermodynamic signatures as useful general guidance for the optimization of ligands or rational drug design.

  17. Histone deacetylase 3 inhibits expression of PUMA in gastric cancer cells.

    PubMed

    Feng, Lifeng; Pan, Min; Sun, Jie; Lu, Haiqi; Shen, Qi; Zhang, Shengjie; Jiang, Tingting; Liu, Liangyi; Jin, Wei; Chen, Yan; Wang, Xian; Jin, Hongchuan

    2013-01-01

    During cancer development, tumor suppressor genes were silenced by promoter methylation or histone deacetylation. Histone deacetylases (HDACs) are important to maintain histone deacetylation. HDAC inhibitors (HDACis) were thus proposed as a new therapeutic approach to cancer. The current study aims to understand the effect and molecular mechanisms of HDACis on gastric cancer cells. Trichostatin A (TSA) significantly inhibited the growth of gastric cancer cells by inducing apoptosis. Gene profiling results showed PUMA (p53 upregulated modulator of apoptosis) as one of 122 genes upregulated in TSA-treated gastric cancer cells. PUMA was downregulated in gastric cancer cell lines and primary gastric carcinoma tissues. Patients with low PUMA expression had significant decreases in overall survival (HR, 2.04; p = 0.047). Ectopic PUMA expression inhibited the growth of gastric cancer cells while PUMA depletion promoted cellular growth. The knockdown of HDAC3 but not other HDACs upregulated PUMA expression. HDAC3 could bind to PUMA promoter, which was abrogated after TSA treatment. In contrast to TSA and SB, HDAC3 siRNA failed to upregulate p53 expression but promoted the interaction of p53 with PUMA promoter. In summary, proapoptotic PUMA was downregulated in gastric cancer and its mRNA expression level is a valuable prognosis factor for gastric cancer. HDAC3 is important to downregulate PUMA expression in gastric cancer and HDACis, like TSA, promoted PUMA expression through stabilizing p53 in addition to HDAC3 inhibition. In combination with chemotherapy, targeting HDAC3 might be a promising strategy to induce apoptosis of gastric cancer cells.

  18. Overexpression of Histone Deacetylase 6 Enhances Resistance to Porcine Reproductive and Respiratory Syndrome Virus in Pigs

    PubMed Central

    Li, Qiuyan; Li, Zhiguo; Wang, Meng; Liu, Lin; Tian, Kegong; Li, Ning

    2017-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically relevant viral pathogens in pigs and causes substantial losses in the pig industry worldwide each year. At present, PRRSV vaccines do not effectively prevent and control this disease. Consequently, it is necessary to develop new antiviral strategies to compensate for the inefficacy of the available vaccines. Histone deacetylase 6 (HDAC6) is an important member of the histone deacetylase family that is responsible for regulating many important biological processes. Studies have shown that HDAC6 has anti-viral activities during the viral life cycle. However, whether HDAC6 overexpression enhances resistance to PRRSV in pigs remains unknown. In this study, we used a somatic cell cloning method to produce transgenic (TG) pigs that constitutively overexpress porcine HDAC6. These TG pigs showed germ line transmission with continued overexpression of HDAC6. In vitro, virus-challenged porcine alveolar macrophages (PAMs) overexpressed HDAC6, which suppressed viral gene expression and PRRSV production. In vivo, resistance to PRRSV in TG pigs was evaluated by direct or cohabitation mediated infection with a highly pathogenic PRRSV (HP-PRRSV) strain. Compared with non-TG (NTG) siblings, TG pigs showed a significantly lower viral load in the lungs and an extended survival time after infection with HP-PRRSV via intramuscular injection. In the cohabitation study, NTG pigs housed with challenged NTG pigs exhibited significantly worse clinical symptoms than the other three in-contact groups. These results collectively suggest that HDAC6 overexpression enhances resistance to PRRSV infection both in vitro and in vivo. Our findings suggest the potential involvement of HDAC6 in the response to PRRSV, which will facilitate the development of novel therapies for PRRSV. PMID:28052127

  19. Glycolysis-dependent histone deacetylase 4 degradation regulates inflammatory cytokine production.

    PubMed

    Wang, Bin; Liu, Ting-Yu; Lai, Chun-Hsiang; Rao, Yan-hua; Choi, Moon-Chang; Chi, Jen-Tsan; Dai, Jian-wu; Rathmell, Jeffrey C; Yao, Tso-Pang

    2014-11-01

    Activation of the inflammatory response is accompanied by a metabolic shift to aerobic glycolysis. Here we identify histone deacetylase 4 (HDAC4) as a new component of the immunometabolic program. We show that HDAC4 is required for efficient inflammatory cytokine production activated by lipopolysaccharide (LPS). Surprisingly, prolonged LPS treatment leads to HDAC4 degradation. LPS-induced HDAC4 degradation requires active glycolysis controlled by GSK3β and inducible nitric oxide synthase (iNOS). Inhibition of GSK3β or iNOS suppresses nitric oxide (NO) production, glycolysis, and HDAC4 degradation. We present evidence that sustained glycolysis induced by LPS treatment activates caspase-3, which cleaves HDAC4 and triggers its degradation. Of importance, a caspase-3-resistant mutant HDAC4 escapes LPS-induced degradation and prolongs inflammatory cytokine production. Our findings identify the GSK3β-iNOS-NO axis as a critical signaling cascade that couples inflammation to metabolic reprogramming and a glycolysis-driven negative feedback mechanism that limits inflammatory response by triggering HDAC4 degradation.

  20. Heart failure: the pivotal role of histone deacetylases.

    PubMed

    Hewitson, Ruth; Dargan, James; Collis, David; Green, Aneta; Moorjani, Narain; Ohri, Sunil; Townsend, Paul A

    2013-02-01

    Heart failure, a state in which cardiac output is unable to meet the metabolic demands of the tissues, poses a significant health burden; following an initial hospital admission with heart failure, five-year mortality is close to 50%. Cardiac hypertrophy, characterised by increased cardiomyocyte size and protein synthesis, has deleterious effects when prolonged and contributes to heart failure. Cardiac hypertrophy itself increases risk of morbidity and mortality. Histone deacetylases are chromatin modifiers which deacetylate the N-terminal tails of histones and have been implicated in common cardiac pathologies associated with hypertrophy. There are 18 histone deacetylases separated into four classes. Class I histone deacetylases interact with heat shock proteins and are pro-hypertrophic, class IIa histone deacetylases repress hypertrophy by inhibiting the activity of transcription factors such as myocyte enhancer factor 2. Histone deacetylases present an exciting new target in combating cardiac hypertrophy and progression to heart failure.

  1. Cystathionine γ-lyase protects vascular endothelium: a role for inhibition of histone deacetylase 6.

    PubMed

    Leucker, Thorsten M; Nomura, Yohei; Kim, Jae Hyung; Bhatta, Anil; Wang, Victor; Wecker, Andrea; Jandu, Sandeep; Santhanam, Lakshmi; Berkowitz, Dan; Romer, Lewis; Pandey, Deepesh

    2017-04-01

    Endothelial cystathionine γ-lyase (CSEγ) contributes to cardiovascular homeostasis, mainly through production of H2S. However, the molecular mechanisms that control CSEγ gene expression in the endothelium during cardiovascular diseases are unclear. The aim of the current study is to determine the role of specific histone deacetylases (HDACs) in the regulation of endothelial CSEγ. Reduced CSEγ mRNA expression and protein abundance were observed in human aortic endothelial cells (HAEC) exposed to oxidized LDL (OxLDL) and in aortas from atherogenic apolipoprotein E knockout (ApoE(-/-)) mice fed a high-fat diet compared with controls. Intact murine aortic rings exposed to OxLDL (50 μg/ml) for 24 h exhibited impaired endothelium-dependent vasorelaxation that was blocked by CSEγ overexpression or the H2S donor NaHS. CSEγ expression was upregulated by pan-HDAC inhibitors and by class II-specific HDAC inhibitors, but not by other class-specific inhibitors. The HDAC6 selective inhibitor tubacin and HDAC6-specific siRNA increased CSEγ expression and blocked OxLDL-mediated reductions in endothelial CSEγ expression and CSEγ promoter activity, indicating that HDAC6 is a specific regulator of CSEγ expression. Consistent with this finding, HDAC6 mRNA, protein expression, and activity were upregulated in OxLDL-exposed HAEC, but not in human aortic smooth muscle cells. HDAC6 protein levels in aortas from high-fat diet-fed ApoE(-/-) mice were comparable to those in controls, whereas HDAC6 activity was robustly upregulated. Together, our findings indicate that HDAC6 is upregulated by atherogenic stimuli via posttranslational modifications and is a critical regulator of CSEγ expression in vascular endothelium. Inhibition of HDAC6 activity may improve endothelial function and prevent or reverse the development of atherosclerosis.NEW & NOTEWORTHY Oxidative injury to endothelial cells by oxidized LDL reduced cystathionine γ-lyase (CSEγ) expression and H2S production

  2. Effects of histone deacetylase inhibitors on amygdaloid histone acetylation and neuropeptide Y expression: a role in anxiety-like and alcohol-drinking behaviours.

    PubMed

    Sakharkar, Amul J; Zhang, Huaibo; Tang, Lei; Baxstrom, Kathryn; Shi, Guangbin; Moonat, Sachin; Pandey, Subhash C

    2014-08-01

    Recent studies have demonstrated the involvement of epigenetic mechanisms in psychiatric disorders, including alcoholism. Here, we investigated the effects of histone deacetylase (HDAC) inhibitor, trichostatin A (TSA) on amygdaloid HDAC-induced histone deacetylation and neuropeptide Y (NPY) expression and on anxiety-like and alcohol-drinking behaviours in alcohol-preferring (P) and -non-preferring (NP) rats. It was found that P rats displayed higher anxiety-like and alcohol-drinking behaviours, higher amygdaloid nuclear, but not cytosolic, HDAC activity, which was associated with increased HDAC2 protein levels and deficits in histone acetylation and NPY expression in the central (CeA) and medial nucleus of amygdala (MeA), as compared to NP rats. TSA treatment attenuated the anxiety-like and alcohol-drinking behaviours, with concomitant reductions in amygdaloid nuclear, but not cytosolic HDAC activity, and HDAC2, but not HDAC4, protein levels in the CeA and MeA of P rats, without effect in NP rats. TSA treatment also increased global histone acetylation (H3-K9 and H4-K8) and NPY expression in the CeA and MeA of P, but not in NP rats. Histone H3 acetylation within the NPY promoter was also innately lower in the amygdala of P rats compared with NP rats; which was normalized by TSA treatment. Voluntary ethanol intake in P, but not NP rats, produced anxiolytic effects and decreased the HDAC2 levels and increased histone acetylation in the CeA and MeA. These results suggest that higher HDAC2 expression-related deficits in histone acetylation may be involved in lower NPY expression in the amygdala of P rats, and operative in controlling anxiety-like and alcohol-drinking behaviours.

  3. Histone deacetylase 2 cell autonomously suppresses excitatory and enhances inhibitory synaptic function in CA1 pyramidal neurons.

    PubMed

    Hanson, Jesse E; Deng, Lunbin; Hackos, David H; Lo, Shih-Ching; Lauffer, Benjamin E; Steiner, Pascal; Zhou, Qiang

    2013-04-03

    Histone deacetylase 2 (HDAC2) negatively regulates excitatory synapse number and memory performance. However, whether HDAC2 regulation of excitatory synapses occurs in a cell-autonomous manner and whether HDAC2 regulates inhibitory synaptic functions are not well understood. To examine these aspects of HDAC2 function, we used sparse transfection of rat hippocampal slice cultures and whole-cell recordings in pyramidal neurons. HDAC2 knockdown (KD) in single postsynaptic pyramidal neurons enhanced, whereas HDAC2 overexpression (OE) reduced, excitatory synaptic transmission. Postsynaptic KD of HDAC2 also facilitated expression of long-term potentiation induced by subthreshold induction stimuli, without altering long-term depression. In contrast, HDAC2 KD reduced, whereas HDAC2 OE enhanced, inhibitory synaptic transmission. Alterations of postsynaptic GABA(A) receptors (GABA(A)Rs) likely underlie the impact of HDAC2 on inhibitory transmission. Consistent with this, we observed reduced transcript and protein levels of the GABA(A)R γ2 subunit and reduced surface expression of the α2 subunit after HDAC2 KD. Furthermore, we observed a reduction in synaptic but not tonic GABA(A)R currents by HDAC2 KD, suggesting that HDAC2 selectively affects synaptic abundance of functional GABA(A)Rs. Immunostaining for postsynaptic GABA(A)Rs confirmed that HDAC2 KD and OE can regulate the synaptic abundance of these receptors. Together, these results highlight a role for HDAC2 in suppressing synaptic excitation and enhancing synaptic inhibition of hippocampal neurons. Therefore, a shift in the balance of synaptic excitation versus inhibition favoring excitation could contribute to the beneficial effects of reducing HDAC2 function in wild-type mice or of inhibiting HDACs in models of cognitive impairment.

  4. Physical and functional interactions of histone deacetylase 3 with TFII-I family proteins and PIASxbeta.

    PubMed

    Tussié-Luna, María Isabel; Bayarsaihan, Dashzeveg; Seto, Edward; Ruddle, Frank H; Roy, Ananda L

    2002-10-01

    TFII-I family proteins are characterized structurally by the presence of multiple reiterated I-repeats, each containing a putative helix-loop-helix domain. Functionally, they behave as multifunctional transcription factors that are activated by a variety of extracellular signals. In studying their subcellular localization, we noticed that these transcription factors frequently reside in subnuclear domains/dots. Because nuclear dots are believed often to harbor components of histone deacetylase enzymes (HDACs), we investigated whether TFII-I family proteins colocalize and interact with HDACs. Here, we show that TFII-I and its related member hMusTRD1/BEN physically and functionally interact with HDAC3. The TFII-I family proteins and HDAC3 also show nearly identical expression patterns in early mouse development. Consistent with our earlier observation that TFII-I family proteins also interact with PIASxbeta, a member of the E3 ligase family involved in the small ubiquitin-like modifier (SUMO) pathway, we show further that PIASxbeta physically and functionally interacts with HDAC3 and relieves the transcriptional repression exerted by HDAC3 upon TFII-I-mediated gene activation. These results suggest a complex interplay between two posttranslational pathways-histone modification and SUMOylation-brokered in part by TFII-I family proteins.

  5. Structural and histone binding ability characterization of the ARB2 domain of a histone deacetylase Hda1 from Saccharomyces cerevisiae

    PubMed Central

    Shen, Hui; Zhu, Yuwei; Wang, Chongyuan; Yan, Hui; Teng, Maikun; Li, Xu

    2016-01-01

    Hda1 is the catalytic core component of the H2B- and H3- specific histone deacetylase (HDAC) complex from Saccharomyces cerevisiae, which is involved in the epigenetic repression and plays a crucial role in transcriptional regulation and developmental events. Though the N-terminal catalytic HDAC domain of Hda1 is well characterized, the function of the C-terminal ARB2 domain remains unknown. In this study, we determine the crystal structure of the ARB2 domain from S. cerevisiae Hda1 at a resolution of 2.7 Å. The ARB2 domain displays an α/β sandwich architecture with an arm protruding outside. Two ARB2 domain molecules form a compact homo-dimer via the arm elements, and assemble as an inverse “V” shape. The pull-down and ITC results reveal that the ARB2 domain possesses the histone binding ability, recognizing both the H2A-H2B dimer and H3-H4 tetramer. Perturbation of the dimer interface abolishes the histone binding ability of the ARB2 domain, indicating that the unique dimer architecture of the ARB2 domain coincides with the function for anchoring to histone. Collectively, our data report the first structure of the ARB2 domain and disclose its histone binding ability, which is of benefit for understanding the deacetylation reaction catalyzed by the class II Hda1 HDAC complex. PMID:27665728

  6. Enhanced Histone Deacetylase Activity in Malignant Melanoma Provokes RAD51 and FANCD2-Triggered Drug Resistance.

    PubMed

    Krumm, Andrea; Barckhausen, Christina; Kücük, Pelin; Tomaszowski, Karl-Heinz; Loquai, Carmen; Fahrer, Jörg; Krämer, Oliver Holger; Kaina, Bernd; Roos, Wynand Paul

    2016-05-15

    DNA-damaging anticancer drugs remain a part of metastatic melanoma therapy. Epigenetic reprogramming caused by increased histone deacetylase (HDAC) activity arising during tumor formation may contribute to resistance of melanomas to the alkylating drugs temozolomide, dacarbazine, and fotemustine. Here, we report on the impact of class I HDACs on the response of malignant melanoma cells treated with alkylating agents. The data show that malignant melanomas in situ contain a high level of HDAC1/2 and malignant melanoma cells overexpress HDAC1/2/3 compared with noncancer cells. Furthermore, pharmacologic inhibition of class I HDACs sensitizes malignant melanoma cells to apoptosis following exposure to alkylating agents, while not affecting primary melanocytes. Inhibition of HDAC1/2/3 caused sensitization of melanoma cells to temozolomide in vitro and in melanoma xenografts in vivo HDAC1/2/3 inhibition resulted in suppression of DNA double-strand break (DSB) repair by homologous recombination because of downregulation of RAD51 and FANCD2. This sensitized cells to the cytotoxic DNA lesion O(6)-methylguanine and caused a synthetic lethal interaction with the PARP-1 inhibitor olaparib. Furthermore, knockdown experiments identified HDAC2 as being responsible for the regulation of RAD51. The influence of class I HDACs on DSB repair by homologous recombination and the possible clinical implication on malignant melanoma therapy with temozolomide and other alkylating drugs suggests a combination approach where class I HDAC inhibitors such as valproic acid or MS-275 (entinostat) appear to counteract HDAC- and RAD51/FANCD2-mediated melanoma cell resistance. Cancer Res; 76(10); 3067-77. ©2016 AACR.

  7. Histone deacetylase enzymes as drug targets for the control of the sheep blowfly, Lucilia cuprina

    PubMed Central

    Kotze, Andrew C.; Hines, Barney M.; Bagnall, Neil H.; Anstead, Clare A.; Gupta, Praveer; Reid, Robert C.; Ruffell, Angela P.; Fairlie, David P.

    2015-01-01

    The Australian sheep blowfly, Lucilia cuprina, is an ecto-parasite that causes significant economic losses in the sheep industry. Emerging resistance to insecticides used to protect sheep from this parasite is driving the search for new drugs that act via different mechanisms. Inhibitors of histone deacetylases (HDACs), enzymes essential for regulating eukaryotic gene transcription, are prospective new insecticides based on their capacity to kill human parasites. The blowfly genome was found here to contain five HDAC genes corresponding to human HDACs 1, 3, 4, 6 and 11. The catalytic domains of blowfly HDACs 1 and 3 have high sequence identity with corresponding human and other Dipteran insect HDACs (Musca domestica and Drosophila melanogaster). On the other hand, HDACs 4, 6 and 11 from the blowfly and the other Dipteran species showed up to 53% difference in catalytic domain amino acids from corresponding human sequences, suggesting the possibility of developing HDAC inhibitors specific for insects as desired for a commercial insecticide. Differences in transcription patterns for different blowfly HDACs through the life cycle, and between the sexes of adult flies, suggest different functions in regulating gene transcription within this organism and possibly different vulnerabilities. Data that supports HDACs as possible new insecticide targets is the finding that trichostatin A and suberoylanilide hydroxamic acid retarded growth of early instar blowfly larvae in vitro, and reduced the pupation rate. Trichostatin A was 8-fold less potent than the commercial insecticide cyromazine in inhibiting larval growth. Our results support further development of inhibitors of blowfly HDACs with selectivity over human and other mammalian HDACs as a new class of prospective insecticides for sheep blowfly. PMID:27120067

  8. Histone deacetylase-3 mediates positive feedback relationship between anaphylaxis and tumor metastasis.

    PubMed

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

    2014-04-25

    Allergic inflammation has been known to enhance the metastatic potential of tumor cells. The role of histone deacetylase-3 (HDAC3) in allergic skin inflammation was reported. We investigated HDAC3 involvement in the allergic inflammation-promotion of metastatic potential of tumor cells. Passive systemic anaphylaxis (PSA) induced HDAC3 expression and FcεRI signaling in BALB/c mice. PSA enhanced the tumorigenic and metastatic potential of mouse melanoma cells in HDAC3- and monocyte chemoattractant protein 1-(MCP1)-dependent manner. The PSA-mediated enhancement of metastatic potential involved the induction of HDAC3, MCP1, and CD11b (a macrophage marker) expression in the lung tumor tissues. We examined an interaction between anaphylaxis and tumor growth and metastasis at the molecular level. Conditioned medium from antigen-stimulated bone marrow-derived mouse mast cell cultures induced the expression of HDAC3, MCP1, and CCR2, a receptor for MCP1, in B16F1 mouse melanoma cells and enhanced migration and invasion potential of B16F1 cells. The conditioned medium from B16F10 cultures induced the activation of FcεRI signaling in lung mast cells in an HDAC3-dependent manner. FcεRI signaling was observed in lung tumors derived from B16F10 cells. Target scan analysis predicted HDAC3 to be as a target of miR-384, and miR-384 and HDAC3 were found to form a feedback regulatory loop. miR-384, which is decreased by PSA, negatively regulated HDAC3 expression, allergic inflammation, and the positive feedback regulatory loop between anaphylaxis and tumor metastasis. We show the miR-384/HDAC3 feedback loop to be a novel regulator of the positive feedback relationship between anaphylaxis and tumor metastasis.

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

    PubMed

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

    2013-11-15

    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.

  10. The role dietary of bioactive compounds on the regulation of histone acetylases and deacetylases: a review.

    PubMed

    Vahid, F; Zand, H; Nosrat-Mirshekarlou, E; Najafi, R; Hekmatdoost, A

    2015-05-10

    Nutrigenomics is an area of epigenomics that explores and defines the rapidly evolving field of diet-genome interactions. Lifestyle and diet can significantly influence epigenetic mechanisms, which cause heritable changes in gene expression without changes in DNA sequence. Nutrient-dependent epigenetic variations can significantly affect genome stability, mRNA and protein expression, and metabolic changes, which in turn influence food absorption and the activity of its constituents. Dietary bioactive compounds can affect epigenetic alterations, which are accumulated over time and are shown to be involved in the pathogenesis of age-related diseases such as diabetes, cancer, and cardiovascular disease. Histone acetylation is an epigenetic modification mediated by histone acetyl transferases (HATs) and histone deacetylases (HDACs) critically involved in regulating affinity binding between the histones and DNA backbone. The HDAC-mediated increase in histone affinity to DNA causes DNA condensation, preventing transcription, whereas HAT-acetylated chromatin is transcriptionally active. HDAC and HAT activities are reported to be associated with signal transduction, cell growth and death, as well as with the pathogenesis of various diseases. The aim of this review was to evaluate the role of diet and dietary bioactive compounds on the regulation of HATs and HDACs in epigenetic diseases. Dietary bioactive compounds such as genistein, phenylisothiocyanate, curcumin, resveratrol, indole-3-carbinol, and epigallocatechin-3-gallate can regulate HDAC and HAT activities and acetylation of histones and non-histone chromatin proteins, and their health benefits are thought to be attributed to these epigenetic mechanisms. The intake of dietary compounds that regulate epigenetic modifications can provide significant health effects and may prevent various pathological processes involved in the development of cancer and other life-threatening diseases.

  11. Substance P induces CCN1 expression via histone deacetylase activity in human colonic epithelial cells.

    PubMed

    Koon, Hon Wai; Shih, David Q; Hing, Tressia C; Chen, Jeremy; Ho, Samantha; Zhao, Dezheng; Targan, Stephan R; Pothoulakis, Charalabos

    2011-11-01

    We have shown that substance P (SP) and its neurokinin-1 receptor (NK-1R) regulate intestinal angiogenesis by increasing expression of protein CYR61 (the cysteine-rich angiogenic inducer 61, or CCN1) in colonic epithelial cells. However, the mechanism involved in SP-induced CCN1 expression has not been studied, and the outcome of increased CCN1 expression in the development of colitis is not fully understood. Because histone deacetylase (HDAC) modulates transcription of several genes involved in inflammation, we investigated participation of HDAC in SP-induced CCN1 expression in human colonic epithelial NCM460 cells overexpressing NK-1R (NCM460-NK-1R) and in primary colonocytes. SP increased HDAC activity with deacetylation and dephosphorylation of nucleosome protein histone H3 in NCM460-NK-1R and/or primary colonocytes. Histone deacetylation and dephosphorylation was observed in colonic mucosa from irritable bowel disease patients. Similarly, colonic mucosal tissues from mice exposed to dextran sulfate sodium showed histone H3 deacetylation and dephosphorylation and increased HDAC activity that was reversed by the NK-1R antagonist CJ-12255. SP-induced increased CCN1 expression in NCM460-NK-1R cells was abolished by pharmacological HDAC inhibition. HDAC overexpression activated basal and SP-induced CCN1 promoter activity. Intracolonic CCN1 overexpression significantly ameliorated dextran sulfate sodium-induced colitis, with reduction of proinflammatory cytokine expression in mice. Thus, SP-mediated CCN1 expression in the inflamed human and mouse colon involves increased HDAC activity. Our results strongly suggest that increased CCN1 expression may be involved in mucosal healing during colitis.

  12. Anti-Inflammatory Effects of Spirulina platensis Extract via the Modulation of Histone Deacetylases

    PubMed Central

    Pham, Tho X.; Park, Young-Ki; Lee, Ji-Young

    2016-01-01

    We previously demonstrated that the organic extract of Spirulina platensis (SPE), an edible blue-green alga, possesses potent anti-inflammatory effects. In this study, we investigated if the regulation of histone deacetylases (HDACs) play a role in the anti-inflammatory effect of SPE in macrophages. Treatment of macrophages with SPE rapidly and dose-dependently reduced HDAC2, 3, and 4 proteins which preceded decreases in their mRNA levels. Degradation of HDAC4 protein was attenuated in the presence of inhibitors of calpain proteases, lysosomal acidification, and Ca2+/calmodulin-dependent protein kinase II, respectively, but not a proteasome inhibitor. Acetylated histone H3 was increased in SPE-treated macrophages to a similar level as macrophages treated with a pan-HDAC inhibitor, with concomitant inhibition of inflammatory gene expression upon LPS stimulation. Knockdown of HDAC3 increased basal and LPS-induced pro-inflammatory gene expression, while HDAC4 knockdown increased basal expression of interleukin-1β (IL-1β), but attenuated LPS-induced inflammatory gene expression. Chromatin immunoprecipitation showed that SPE decreased p65 binding and H3K9/K14 acetylation at the Il-1β and tumor necrosis factor α (Tnfα) promoters. Our results suggest that SPE increased global histone H3 acetylation by facilitating HDAC protein degradation, but decreases histone H3K9/K14 acetylation and p65 binding at the promoters of Il-1β and Tnfα to exert its anti-inflammatory effect. PMID:27338466

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

    PubMed Central

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

    2014-01-01

    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 γH2AX 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

  14. Expression and functional analysis of the plant-specific histone deacetylase HDT701 in rice

    PubMed Central

    Zhao, Jinhui; Zhang, Jianxia; Zhang, Wei; Wu, Kunlin; Zheng, Feng; Tian, Lining; Liu, Xuncheng; Duan, Jun

    2015-01-01

    Reversible histone acetylation and deacetylation at the N-terminus of histone tails play a crucial role in regulating eukaryotic gene activity. Acetylation of core histones is associated with gene activation, whereas deacetylation of histone is often correlated with gene repression. The level of histone acetylation is antagonistically catalyzed by histone acetyltransferases citation(HATs) and histone deacetylases (HDACs). In this work, we examined the subcellular localization, expression pattern and function of HDT701, a member of the plant-specific HD2-type histone deacetylase in rice. HDT701 is localized at the subcellular level in the nucleus. Histochemical GUS-staining analysis revealed that HDT701 is constitutively expressed throughout the life cycle of rice. Overexpression of HDT701 in rice decreases ABA, salt and osmotic stress resistance during seed germination. Delayed seed germination of HDT701 overexpression lines is associated with decreased histone H4 acetylation and down-regulated expression of GA biosynthetic genes. Moreover, overexpression of HDT701 in rice enhances salt and osmotic stress resistance during the seedling stage. Taken together, our findings suggested that HDT701 may play an important role in regulating seed germination in response to abiotic stresses in rice. PMID:25653654

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

    PubMed

    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

    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.

  16. Valproic Acid Limits Pancreatic Recovery after Pancreatitis by Inhibiting Histone Deacetylases and Preventing Acinar Redifferentiation Programs.

    PubMed

    Eisses, John F; Criscimanna, Angela; Dionise, Zachary R; Orabi, Abrahim I; Javed, Tanveer A; Sarwar, Sheharyar; Jin, Shunqian; Zhou, Lili; Singh, Sucha; Poddar, Minakshi; Davis, Amy W; Tosun, Akif Burak; Ozolek, John A; Lowe, Mark E; Monga, Satdarshan P; Rohde, Gustavo K; Esni, Farzad; Husain, Sohail Z

    2015-12-01

    The mechanisms by which drugs induce pancreatitis are unknown. A definite cause of pancreatitis is due to the antiepileptic drug valproic acid (VPA). On the basis of three crucial observations-that VPA inhibits histone deacetylases (HDACs), HDACs mediate pancreas development, and aspects of pancreas development are recapitulated during recovery of the pancreas after injury-we hypothesized that VPA does not cause injury on its own, but it predisposes patients to pancreatitis by inhibiting HDACs and provoking an imbalance in pancreatic recovery. In an experimental model of pancreatic injury, we found that VPA delayed recovery of the pancreas and reduced acinar cell proliferation. In addition, pancreatic expression of class I HDACs (which are the primary VPA targets) increased in the midphase of pancreatic recovery. VPA administration inhibited pancreatic HDAC activity and led to the persistence of acinar-to-ductal metaplastic complexes, with prolonged Sox9 expression and sustained β-catenin nuclear activation, findings that characterize a delay in regenerative reprogramming. These effects were not observed with valpromide, an analog of VPA that lacks HDAC inhibition. This is the first report, to our knowledge, that VPA shifts the balance toward pancreatic injury and pancreatitis through HDAC inhibition. The work also identifies a new paradigm for therapies that could exploit epigenetic reprogramming to enhance pancreatic recovery and disorders of pancreatic injury.

  17. Effects of the Histone Deacetylase Inhibitor Valproic Acid on Human Pericytes In Vitro

    PubMed Central

    Friman, Tomas; Dencker, Lennart; Sundberg, Christian; Scholz, Birger

    2011-01-01

    Microvascular pericytes are of key importance in neoformation of blood vessels, in stabilization of newly formed vessels as well as maintenance of angiostasis in resting tissues. Furthermore, pericytes are capable of differentiating into pro-fibrotic collagen type I producing fibroblasts. The present study investigates the effects of the histone deacetylase (HDAC) inhibitor valproic acid (VPA) on pericyte proliferation, cell viability, migration and differentiation. The results show that HDAC inhibition through exposure of pericytes to VPA in vitro causes the inhibition of pericyte proliferation and migration with no effect on cell viability. Pericyte exposure to the potent HDAC inhibitor Trichostatin A caused similar effects on pericyte proliferation, migration and cell viability. HDAC inhibition also inhibited pericyte differentiation into collagen type I producing fibroblasts. Given the importance of pericytes in blood vessel biology a qPCR array focusing on the expression of mRNAs coding for proteins that regulate angiogenesis was performed. The results showed that HDAC inhibition promoted transcription of genes involved in vessel stabilization/maturation in human microvascular pericytes. The present in vitro study demonstrates that VPA influences several aspects of microvascular pericyte biology and suggests an alternative mechanism by which HDAC inhibition affects blood vessels. The results raise the possibility that HDAC inhibition inhibits angiogenesis partly through promoting a pericyte phenotype associated with stabilization/maturation of blood vessels. PMID:21966390

  18. Histone deacetylase mediated silencing of AMWAP expression contributes to cisplatin nephrotoxicity

    PubMed Central

    Ranganathan, Punithavathi; Hamad, Rania; Mohamed, Riyaz; Jayakumar, Calpurnia; Muthusamy, Thangaraju; Ramesh, Ganesan

    2015-01-01

    Cisplatin-induced acute kidney injury is a serious problem in cancer patients during treatment of solid tumors. Currently, there are no therapies available to treat or prevent cisplatin nephrotoxicity. Since histone deacetylase (HDAC) inhibition augments cisplatin anti-tumor activity, we tested whether HDAC inhibitors can prevent cisplatin-induced nephrotoxicity and determined the underlying mechanism. Cisplatin up-regulated the expression of several HDACs in the kidney. Inhibition of HDAC with clinically used trichostatin A suppressed cisplatin-induced kidney injury, inflammation and epithelial cell apoptosis. Moreover, trichostatin A upregulated the novel anti-inflammatory protein, activated microglia/macrophage WAP domain protein (AMWAP), in epithelial cells which was enhanced with cisplatin treatment. Interestingly, HDAC1 and -2 specific inhibitors are sufficient to potently up-regulate AMWAP in epithelial cells. Administration of recombinant AMWAP or its epithelial cell-specific overexpression reduced cisplatin-induced kidney dysfunction. Moreover, AMWAP treatment suppressed epithelial cell apoptosis, and siRNA-based knockdown of AMWAP expression abolished trichostatin A-mediated suppression of epithelial cell apoptosis in vitro. Thus, HDAC-mediated silencing of AMWAP may contribute to cisplatin nephrotoxicity. Hence, HDAC1 and -2 specific inhibitors or AMWAP could be useful therapeutic agents for the prevention of cisplatin nephrotoxicity. PMID:26509586

  19. Valproic Acid Limits Pancreatic Recovery after Pancreatitis by Inhibiting Histone Deacetylases and Preventing Acinar Redifferentiation Programs

    PubMed Central

    Eisses, John F.; Criscimanna, Angela; Dionise, Zachary R.; Orabi, Abrahim I.; Javed, Tanveer A.; Sarwar, Sheharyar; Jin, Shunqian; Zhou, Lili; Singh, Sucha; Poddar, Minakshi; Davis, Amy W.; Tosun, Akif Burak; Ozolek, John A.; Lowe, Mark E.; Monga, Satdarshan P.; Rohde, Gustavo K.; Esni, Farzad; Husain, Sohail Z.

    2016-01-01

    The mechanisms by which drugs induce pancreatitis are unknown. A definite cause of pancreatitis is due to the antiepileptic drug valproic acid (VPA). On the basis of three crucial observations—that VPA inhibits histone deacetylases (HDACs), HDACs mediate pancreas development, and aspects of pancreas development are recapitulated during recovery of the pancreas after injury—we hypothesized that VPA does not cause injury on its own, but it predisposes patients to pancreatitis by inhibiting HDACs and provoking an imbalance in pancreatic recovery. In an experimental model of pancreatic injury, we found that VPA delayed recovery of the pancreas and reduced acinar cell proliferation. In addition, pancreatic expression of class I HDACs (which are the primary VPA targets) increased in the midphase of pancreatic recovery. VPA administration inhibited pancreatic HDAC activity and led to the persistence of acinar-to-ductal metaplastic complexes, with prolonged Sox9 expression and sustained β-catenin nuclear activation, findings that characterize a delay in regenerative reprogramming. These effects were not observed with valpromide, an analog of VPA that lacks HDAC inhibition. This is the first report, to our knowledge, that VPA shifts the balance toward pancreatic injury and pancreatitis through HDAC inhibition. The work also identifies a new paradigm for therapies that could exploit epigenetic reprogramming to enhance pancreatic recovery and disorders of pancreatic injury. PMID:26476347

  20. MeCP2 and Histone Deacetylases 1 and 2 in Dorsal Striatum Collectively Suppress Repetitive Behaviors

    PubMed Central

    Mahgoub, Melissa; Adachi, Megumi; Suzuki, Kanzo; Liu, Xihui; Kavalali, Ege T.; Chahrour, Maria H.; Monteggia, Lisa M.

    2016-01-01

    Class I histone deacetylases (HDACs), HDAC1 and HDAC2 often associate together in protein complexes with transcriptional factors such as methyl-CpG-binding protein 2 (MeCP2). Given their high degree of sequence identity, we examined the functional redundancy of HDAC1 and HDAC2 in mature brain. We demonstrate that postnatal forebrain-specific deletion of both HDAC1 and HDAC2 in mice impacts neuronal survival and results in an excessive grooming phenotype caused by dysregulation of the obsessive-compulsive disorder-implicated gene SAP90/PSD-95-associated protein 3 (SAPAP3) in striatum. Moreover, HDAC1- and HDAC2-dependent regulation of SAPAP3 expression requires Mecp2, the gene involved in the pathophysiology of Rett syndrome. We show that postnatal forebrain-specific deletion of Mecp2 causes excessive grooming, which is rescued by restoring striatal Sapap3 expression. Our results provide novel insight into the upstream regulation of SAPAP3, and establish the essential role of striatal HDAC1, HDAC2, and MeCP2 for suppression of repetitive behaviors. PMID:27668390

  1. Destabilization of ERBB2 transcripts by targeting 3' untranslated region messenger RNA associated HuR and histone deacetylase-6.

    PubMed

    Scott, Gary K; Marx, Corina; Berger, Crystal E; Saunders, Laura R; Verdin, Eric; Schäfer, Stefan; Jung, Manfred; Benz, Christopher C

    2008-07-01

    In addition to repressing ERBB2 promoter function, histone deacetylase (HDAC) inhibitors induce the accelerated decay of mature ERBB2 transcripts; the mechanism mediating this transcript destabilization is unknown but depends on the 3' untranslated region (UTR) of ERBB2 mRNA. Using ERBB2-overexpressing human breast cancer cells (SKBR3), the mRNA stability factor HuR was shown to support ERBB2 transcript integrity, bind and endogenously associate with a conserved U-rich element within the ERBB2 transcript 3' UTR, coimmunoprecipitate with RNA-associated HDAC activity, and colocalize with HDAC6. HDAC6 also coimmunoprecipitates with HuR in an RNA-dependent manner and within 6 hours of exposure to a pan-HDAC inhibitor dose, that does not significantly alter cytosolic HuR levels or HuR binding to ERBB2 mRNA. Cellular ERBB2 transcript levels decline while remaining physically associated with HDAC6. Knockdown of HDAC6 protein by small interfering RNA partially suppressed the ERBB2 transcript decay induced by either pan-HDAC or HDAC6-selective enzymatic inhibitors. Three novel hydroxamates, ST71, ST17, and ST80 were synthesized and shown to inhibit HDAC6 with 14-fold to 31-fold greater selectivity over their binding and inhibition of HDAC1. Unlike more potent pan-HDAC inhibitors, these HDAC6-selective inhibitors produced dose-dependent growth arrest of ERBB2-overexpressing breast cancer cells by accelerating the decay of mature ERBB2 mRNA without repressing ERBB2 promoter function. In sum, these findings point to the therapeutic potential of HuR and HDAC6-selective inhibitors, contrasting ERBB2 stability effects induced by HDAC6 enzymatic inhibition and HDAC6 protein knockdown, and show that ERBB2 transcript stability mechanisms include exploitable targets for the development of novel anticancer therapies.

  2. HDAC inhibition imparts beneficial transgenerational effects in Huntington's disease mice via altered DNA and histone methylation

    PubMed Central

    Jia, Haiqun; Morris, Charles D.; Williams, Roy M.; Loring, Jeanne F.; Thomas, Elizabeth A.

    2015-01-01

    Increasing evidence has demonstrated that epigenetic factors can profoundly influence gene expression and, in turn, influence resistance or susceptibility to disease. Epigenetic drugs, such as histone deacetylase (HDAC) inhibitors, are finding their way into clinical practice, although their exact mechanisms of action are unclear. To identify mechanisms associated with HDAC inhibition, we performed microarray analysis on brain and muscle samples treated with the HDAC1/3-targeting inhibitor, HDACi 4b. Pathways analyses of microarray datasets implicate DNA methylation as significantly associated with HDAC inhibition. Further assessment of DNA methylation changes elicited by HDACi 4b in human fibroblasts from normal controls and patients with Huntington’s disease (HD) using the Infinium HumanMethylation450 BeadChip revealed a limited, but overlapping, subset of methylated CpG sites that were altered by HDAC inhibition in both normal and HD cells. Among the altered loci of Y chromosome-linked genes, KDM5D, which encodes Lys (K)-specific demethylase 5D, showed increased methylation at several CpG sites in both normal and HD cells, as well as in DNA isolated from sperm from drug-treated male mice. Further, we demonstrate that first filial generation (F1) offspring from drug-treated male HD transgenic mice show significantly improved HD disease phenotypes compared with F1 offspring from vehicle-treated male HD transgenic mice, in association with increased Kdm5d expression, and decreased histone H3 Lys4 (K4) (H3K4) methylation in the CNS of male offspring. Additionally, we show that overexpression of Kdm5d in mutant HD striatal cells significantly improves metabolic deficits. These findings indicate that HDAC inhibitors can elicit transgenerational effects, via cross-talk between different epigenetic mechanisms, to have an impact on disease phenotypes in a beneficial manner. PMID:25535382

  3. Decreased histone deacetylase 2 impairs Nrf2 activation by oxidative stress

    SciTech Connect

    Mercado, Nicolas; Thimmulappa, Rajesh; Thomas, Catherine M.R.; Fenwick, Peter S.; Chana, Kirandeep K.; Donnelly, Louise E.; Biswal, Shyam; Ito, Kazuhiro; Barnes, Peter J.

    2011-03-11

    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.

  4. Selective Inhibitors of Histone Deacetylases 1 and 2 Synergize with Azacitidine in Acute Myeloid Leukemia

    PubMed Central

    Shearstone, Jeffrey R.; Quayle, Steven N.; Huang, Pengyu; van Duzer, John H.; Jarpe, Matthew B.; Jones, Simon S.; Yang, Min

    2017-01-01

    Acute myeloid leukemia (AML) is a heterogeneous group of hematopoietic stem cell disorders characterized by defects in myeloid differentiation and increased proliferation of neoplastic hematopoietic precursor cells. Outcomes for patients with AML remain poor, highlighting the need for novel treatment options. Aberrant epigenetic regulation plays an important role in the pathogenesis of AML, and inhibitors of DNA methyltransferase or histone deacetylase (HDAC) enzymes have exhibited activity in preclinical AML models. Combination studies with HDAC inhibitors plus DNA methyltransferase inhibitors have potential beneficial clinical activity in AML, however the toxicity profiles of non-selective HDAC inhibitors in the combination setting limit their clinical utility. In this work, we describe the preclinical development of selective inhibitors of HDAC1 and HDAC2, which are hypothesized to have improved safety profiles, for combination therapy in AML. We demonstrate that selective inhibition of HDAC1 and HDAC2 is sufficient to achieve efficacy both as a single agent and in combination with azacitidine in preclinical models of AML, including established AML cell lines, primary leukemia cells from AML patient bone marrow samples and in vivo xenograft models of human AML. Gene expression profiling of AML cells treated with either an HDAC1/2 inhibitor, azacitidine, or the combination of both have identified a list of genes involved in transcription and cell cycle regulation as potential mediators of the combinatorial effects of HDAC1/2 inhibition with azacitidine. Together, these findings support the clinical evaluation of selective HDAC1/2 inhibitors in combination with azacitidine in AML patients. PMID:28060870

  5. Autophagy potentiates the anti-cancer effects of the histone deacetylase inhibitors in hepatocellular carcinoma.

    PubMed

    Liu, Yuan-Ling; Yang, Pei-Ming; Shun, Chia-Tung; Wu, Ming-Shiang; Weng, Jing-Ru; Chen, Ching-Chow

    2010-11-01

    Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death worldwide. Drug treatments for HCC have been largely unsuccessful. Histone deacetylase inhibitors can reactivate tumor suppressor genes in cancer cells and serve as potential anti-cancer drugs. Two potent HDAC inhibitors OSU-HDAC42 and SAHA induced autophagy in HCC cells as revealed by transmission electron microscopy, immunofluorescence and LC3-II accumulation. We found that SAHA and OSU-HDAC42 induced autophagy through downregulation of Akt/mTOR signaling and induction of ER stress response. Inhibition of autophagy by 3-MA or Atg5 knockout reduced SAHA-induced cytotoxicity, indicating that SAHA-induced autophagy led to cell death. Our results show that the combination of autophagy inducers with SAHA might be attractive for the treatment of HCC and pharmacological targeting of autophagy provides promise for the management of cancer therapy.

  6. Chemical Inhibition of Histone Deacetylases 1 and 2 Induces Fetal Hemoglobin through Activation of GATA2.

    PubMed

    Shearstone, Jeffrey R; Golonzhka, Olga; Chonkar, Apurva; Tamang, David; van Duzer, John H; Jones, Simon S; Jarpe, Matthew B

    2016-01-01

    Therapeutic intervention aimed at reactivation of fetal hemoglobin protein (HbF) is a promising approach for ameliorating sickle cell disease (SCD) and β-thalassemia. Previous studies showed genetic knockdown of histone deacetylase (HDAC) 1 or 2 is sufficient to induce HbF. Here we show that ACY-957, a selective chemical inhibitor of HDAC1 and 2 (HDAC1/2), elicits a dose and time dependent induction of γ-globin mRNA (HBG) and HbF in cultured primary cells derived from healthy individuals and sickle cell patients. Gene expression profiling of erythroid progenitors treated with ACY-957 identified global changes in gene expression that were significantly enriched in genes previously shown to be affected by HDAC1 or 2 knockdown. These genes included GATA2, which was induced greater than 3-fold. Lentiviral overexpression of GATA2 in primary erythroid progenitors increased HBG, and reduced adult β-globin mRNA (HBB). Furthermore, knockdown of GATA2 attenuated HBG induction by ACY-957. Chromatin immunoprecipitation and sequencing (ChIP-Seq) of primary erythroid progenitors demonstrated that HDAC1 and 2 occupancy was highly correlated throughout the GATA2 locus and that HDAC1/2 inhibition led to elevated histone acetylation at well-known GATA2 autoregulatory regions. The GATA2 protein itself also showed increased binding at these regions in response to ACY-957 treatment. These data show that chemical inhibition of HDAC1/2 induces HBG and suggest that this effect is mediated, at least in part, by histone acetylation-induced activation of the GATA2 gene.

  7. Chemical Inhibition of Histone Deacetylases 1 and 2 Induces Fetal Hemoglobin through Activation of GATA2

    PubMed Central

    Golonzhka, Olga; Chonkar, Apurva; Tamang, David; van Duzer, John H.; Jones, Simon S.; Jarpe, Matthew B.

    2016-01-01

    Therapeutic intervention aimed at reactivation of fetal hemoglobin protein (HbF) is a promising approach for ameliorating sickle cell disease (SCD) and β-thalassemia. Previous studies showed genetic knockdown of histone deacetylase (HDAC) 1 or 2 is sufficient to induce HbF. Here we show that ACY-957, a selective chemical inhibitor of HDAC1 and 2 (HDAC1/2), elicits a dose and time dependent induction of γ-globin mRNA (HBG) and HbF in cultured primary cells derived from healthy individuals and sickle cell patients. Gene expression profiling of erythroid progenitors treated with ACY-957 identified global changes in gene expression that were significantly enriched in genes previously shown to be affected by HDAC1 or 2 knockdown. These genes included GATA2, which was induced greater than 3-fold. Lentiviral overexpression of GATA2 in primary erythroid progenitors increased HBG, and reduced adult β-globin mRNA (HBB). Furthermore, knockdown of GATA2 attenuated HBG induction by ACY-957. Chromatin immunoprecipitation and sequencing (ChIP-Seq) of primary erythroid progenitors demonstrated that HDAC1 and 2 occupancy was highly correlated throughout the GATA2 locus and that HDAC1/2 inhibition led to elevated histone acetylation at well-known GATA2 autoregulatory regions. The GATA2 protein itself also showed increased binding at these regions in response to ACY-957 treatment. These data show that chemical inhibition of HDAC1/2 induces HBG and suggest that this effect is mediated, at least in part, by histone acetylation-induced activation of the GATA2 gene. PMID:27073918

  8. Evaluation of histone deacetylase inhibitors (HDACi) as therapeutic leads for human African trypanosomiasis (HAT).

    PubMed

    Carrillo, Angela K; Guiguemde, W Armand; Guy, R Kiplin

    2015-08-15

    Two of the histone deacetylases, TbDAC1 and TbDAC3, have been reported to be essential genes in trypanosomes. Therefore, we tested the activity of a panel of human histone deacetylase inhibitors (HDACi) for their ability to block proliferation of Trypanosoma brucei brucei. Among the HDACi's, the hydroxamic acid derivatives panobinostat and belinostat exhibited potency that appeared to make them viable candidates for development due to their reported pharmacokinetic characteristics. However, cellular pharmacodynamic analysis demonstrated that these drugs were unable to kill cultured parasites at exposures seen in patients at their tolerated doses and additionally failed to show any synergistic effects in combination with pentamidine, suramin, melarsoprol, or nifurtimox. Analysis of the potency of the entire HDACi panel revealed no correlations between potency against any human HDAC isoform and inhibition of T. brucei proliferation, suggesting that the trypanosome histone deacetylases possess a unique specificity. These studies confirmed that HDAC inhibitors have potential as leads against human African trypanosomiasis but that none of the current clinical candidates can be directly repurposed. Therefore, development of HDACi's with appropriate specificity and potency may be a viable route to a new class of anti-trypanosomal drugs.

  9. Therapeutic Effect of Histone Deacetylase Inhibitor, Sodium Butyrate, on Allergic Rhinitis In Vivo.

    PubMed

    Wang, Jie; Wen, Liting; Wang, Ye; Chen, Fuquan

    2016-04-01

    Despite the well-documented therapeutic effects of histone deacetylase inhibitor (HDACi) on various diseases, including arthritis and asthma, the therapeutic effect of HDACi on allergic rhinitis remains unmentioned in the literature. This study investigated the therapeutic effect of sodium butyrate (SoB), a form of HDACi, on mice with allergic rhinitis. The results showed that the expression levels of histone deacetylase 1 (HDAC1), histone deacetylase 3 (HDAC3), and thymic stromal lymphopoietin (TSLP) were significantly upregulated in mice with allergic rhinitis, whereas H3 acetylation at lysine 9 (H3AcK9) was decreased. The intranasal application of SoB inhibited the expression levels of TSLP levels and upregulated the expression of H3AcK9 in a mouse model of allergic rhinitis. Furthermore, SoB treatment significantly decreased the increased levels of ovalbumin-specific IgE and improved clinical symptoms and nasal mucosa epithelial morphology in the mouse model of allergic rhinitis. In addition, we further demonstrated that SoB treatment significantly increased the serum levels of IL-2 and IFN-γ and decreased the serum levels of IL-4 and IL-10, correcting the Th1/Th2 imbalance in the mouse model of allergic rhinitis. Taken together, our study suggests that SoB has the potential to treat allergic rhinitis.

  10. Structure of the histone deacetylase SIRT2.

    PubMed

    Finnin, M S; Donigian, J R; Pavletich, N P

    2001-07-01

    Sir2 is an NAD-dependent histone deacetylase that mediates transcriptional silencing at mating-type loci, telomeres and ribosomal gene clusters, and has a critical role in the determination of life span in yeast and Caenorhabditis elegans. The 1.7 A crystal structure of the 323 amino acid catalytic core of human SIRT2, a homolog of yeast Sir2, reveals an NAD-binding domain, which is a variant of the Rossmann fold, and a smaller domain composed of a helical module and a zinc-binding module. A conserved large groove at the interface of the two domains is the likely site of catalysis based on mutagenesis. Intersecting this large groove, there is a pocket formed by the helical module. The pocket is lined with hydrophobic residues conserved within each of the five Sir2 classes, suggesting that it is a class-specific protein-binding site.

  11. Detrimental effect of class-selective histone deacetylase inhibitors during tissue regeneration following hindlimb ischemia.

    PubMed

    Spallotta, Francesco; Tardivo, Silvia; Nanni, Simona; Rosati, Jessica D; Straino, Stefania; Mai, Antonello; Vecellio, Matteo; Valente, Sergio; Capogrossi, Maurizio C; Farsetti, Antonella; Martone, Julie; Bozzoni, Irene; Pontecorvi, Alfredo; Gaetano, Carlo; Colussi, Claudia

    2013-08-09

    Histone deacetylase inhibitors (DIs) are promising drugs for the treatment of several pathologies including ischemic and failing heart where they demonstrated efficacy. However, adverse side effects and cardiotoxicity have also been reported. Remarkably, no information is available about the effect of DIs during tissue regeneration following acute peripheral ischemia. In this study, mice made ischemic by femoral artery excision were injected with the DIs MS275 and MC1568, selective for class I and IIa histone deacetylases (HDACs), respectively. In untreated mice, soon after damage, class IIa HDAC phosphorylation and nuclear export occurred, paralleled by dystrophin and neuronal nitric-oxide synthase (nNOS) down-regulation and decreased protein phosphatase 2A activity. Between 14 and 21 days after ischemia, dystrophin and nNOS levels recovered, and class IIa HDACs relocalized to the nucleus. In this condition, the MC1568 compound increased the number of newly formed muscle fibers but delayed their terminal differentiation, whereas MS275 abolished the early onset of the regeneration process determining atrophy and fibrosis. The selective DIs had differential effects on the vascular compartment: MC1568 increased arteriogenesis whereas MS275 inhibited it. Capillarogenesis did not change. Chromatin immunoprecipitations revealed that class IIa HDAC complexes bind promoters of proliferation-associated genes and of class I HDAC1 and 2, highlighting a hierarchical control between class II and I HDACs during tissue regeneration. Our findings indicate that class-selective DIs interfere with normal mouse ischemic hindlimb regeneration and suggest that their use could be limited by alteration of the regeneration process in peripheral ischemic tissues.

  12. [Design, synthesis, and biological activities of histone deacetylase inhibitors with diketo ester as zinc binding group].

    PubMed

    Lu, Hui; Su, Hong; Yang, Bo; You, Qi-Dong

    2011-03-01

    Histone deacetylases (HDACs) inhibition causes hyperacetylation of histones leading to growth arrest, differentiation and apoptosis of tumor cells, representing a new strategy in cancer therapy. Many of previously reported HDACs inhibitors are hydroxamic acid derivatives, which could chelate the zinc ion in the active site in a bidentate fashion. However, hydroxamic acids occasionally have produced problems such as poor pharmacokinetics, severe toxicity and low selectivity. Herein we describe the identification of a new series of non-hydroxamate HDACs inhibitors bearing diketo ester moieties as zinc binding group. HDACs inhibition assay and antiproliferation assays in vitro against multiple cancer cell lines were used for evaluation. These compounds displayed low antiproliferative activity against solid tumor cells, while good antiproliferative activity against human leukemic monocyte lymphoma cell line U937. Compound CPUYS707 is the best with GI50 value of 0.31 micromol x L(-1) against U937 cells, which is more potent than SAHA and MS-275. HDACs inhibition activity of these compounds is lower than that expected, further evaluation is needed.

  13. A novel histone deacetylase 1 and 2 isoform-specific inhibitor alleviates experimental Parkinson's disease.

    PubMed

    Choong, Chi-Jing; Sasaki, Tsutomu; Hayakawa, Hideki; Yasuda, Toru; Baba, Kousuke; Hirata, Yoshiyuki; Uesato, Shinichi; Mochizuki, Hideki

    2016-01-01

    With increased histone deacetylase (HDAC) activity and histone hypoacetylation being implicated in neurodegeneration, HDAC inhibitors have been reported to have considerable therapeutic potential. Yet, existing inhibitors lack specificity and may show substantial adverse effect. In this study, we identified a novel HDAC1/2 isoform-specific inhibitor, K560, with protective effects against 1-methyl-4-phenylpyridinium (MPP(+))- and/or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neuronal death in both in vitro and in vivo Parkinson's disease model. K560 attenuated cell death induced by MPP(+) in differentiated SH-SY5Y cells through the sustained expression of an antiapoptotic protein, X-linked inhibitor of apoptosis (XIAP). Inhibition of XIAP expression by locked nucleic acid antisense oligonucleotides abolished the protective effect of K560. Inactivation of mitogen-activated protein kinase cascades, reduced p53 phosphorylation, and down-regulation of p53-upregulated modulator of apoptosis on K560 treatment were also observed. Furthermore, pre- and post-oral administration of K560 to mice prevented MPTP-induced loss of dopaminergic neurons in substantia nigra, suggesting that selective inhibition of HDAC1 and HDAC2 by K560 may pave the way to new strategies for Parkinson's disease treatment.

  14. Klotho preservation via histone deacetylase inhibition attenuates chronic kidney disease-associated bone injury in mice

    PubMed Central

    Lin, Wenjun; Li, Yanning; chen, Fang; Yin, Shasha; Liu, Zhihong; Cao, Wangsen

    2017-01-01

    Bone loss and increased fracture are the devastating outcomes of chronic kidney disease-mineral and bone disorder (CKD-MBD) resulting from Klotho deficit-related mineral disturbance and hyperparathyroidism. Because Klotho down-regulation after renal injury is presumably affected by aberrant histone deacetylase (HDAC) activities, here we assess whether HDAC inhibition prevents Klotho loss and attenuates the CKD-associated bone complication in a mouse model of CKD-MBD. Mice fed adenine-containing diet developed the expected renal damage, a substantial Klotho loss and the deregulated key factors causally affecting bone remodeling, which were accompanied by a marked reduction of bone mineral density. Intriguingly, administration of a potent HDAC inhibitor trichostatin A (TSA) impressively alleviated the Klotho deficit and the observed alterations of serum, kidney and bone. TSA prevented Klotho loss by increasing the promoter-associated histone acetylation, therefore increasing Klotho transcription. More importantly the mice lacking Klotho by siRNA interference largely abolished the TSA protections against the serum and renal abnormalities, and the deranged bone micro-architectures. Thus, our study identified Klotho loss as a key event linking HDAC deregulation to the renal and bone injuries in CKD-MBD mice and demonstrated the therapeutic potentials of endogenous Klotho restoration by HDAC inhibition in treating CKD and the associated extrarenal complications. PMID:28387374

  15. Regulation of androgen receptor and histone deacetylase 1 by Mdm2-mediated ubiquitylation.

    PubMed

    Gaughan, Luke; Logan, Ian R; Neal, David E; Robson, Craig N

    2005-01-01

    The androgen receptor (AR) is a member of the nuclear hormone receptor family of transcription factors and plays a critical role in regulating the expression of genes involved in androgen-dependent and -independent tumour formation. Regulation of the AR is achieved by alternate binding of either histone acetyltransferase (HAT)-containing co-activator proteins, or histone deacetylase 1 (HDAC1). Factors that control AR stability may also constitute an important regulatory mechanism, a notion that has been confirmed with the finding that the AR is a direct target for Mdm2-mediated ubiquitylation and proteolysis. Using chromatin immunoprecipitation (ChIP) and re-ChIP analyses, we show that Mdm2 associates with AR and HDAC1 at the active androgen-responsive PSA promoter in LNCaP prostate cancer cells. Furthermore, we demonstrate that Mdm2-mediated modification of AR and HDAC1 catalyses protein destabilization and attenuates AR sactivity, suggesting that ubiquitylation of the AR and HDAC1 may constitute an additional mechanism for regulating AR function. We also show that HDAC1 and Mdm2 function co-operatively to reduce AR-mediated transcription that is attenuated by the HAT activity of the AR co-activator Tip60, suggesting interplay between acetylation status and receptor ubiquitylation in AR regulation. In all, our data indicates a novel role for Mdm2 in regulating components of the AR transcriptosome.

  16. Towards selective inhibition of histone deacetylase isoforms: what has been achieved, where we are and what will be next.

    PubMed

    Thaler, Florian; Mercurio, Ciro

    2014-03-01

    Histone deacetylases (HDACs) are widely studied targets for the treatment of cancer and other diseases. Up to now, over twenty HDAC inhibitors have entered clinical studies and two of them have already reached the market, namely the hydroxamic acid derivative SAHA (vorinostat, Zolinza) and the cyclic depsipeptide FK228 (romidepsin, Istodax) that have been approved for the treatment of cutaneous T-cell lymphoma (CTCL). A common aspect of the first HDAC inhibitors is the absence of any particular selectivity towards specific isozymes. Some of molecules resulted to be “pan”-HDAC inhibitors, while others are class I selective. In the meantime, the knowledge of HDAC biology has continuously progressed. Key advances in the structural biology of various isozymes, reliable molecular homology models as well as suitable biological assays have provided new tools for drug discovery activities. This Minireview aims at surveying these recent developments as well as the design, synthesis and biological characterization of isoform-selective derivatives.

  17. Second-generation histone deacetylase 6 inhibitors enhance the immunosuppressive effects of Foxp3+ T-regulatory cells.

    PubMed

    Kalin, Jay H; Butler, Kyle V; Akimova, Tatiana; Hancock, Wayne W; Kozikowski, Alan P

    2012-01-26

    Second-generation Tubastatin A analogues were synthesized and evaluated for their ability to inhibit selectively histone deacetylase 6 (HDAC6). Substitutions to the carboline cap group were well-tolerated with substitution at the 2-position of both β- and γ-carbolines being optimal for HDAC6 activity and selectivity. Some compounds in this series were determined to have subnanomolar activity at HDAC6 with more than 7000 fold selectivity for HDAC6 versus HDAC1. Selected compounds were then evaluated for their ability to augment the immunosuppressive effect of Foxp3+ regulatory T cells. All compounds tested were found to enhance the ability of regulatory T cells to inhibit the mitotic division of effector T cells both in vitro and in vivo, suggesting that further investigation into the use of these compounds for the treatment of autoimmune disorders is warranted.

  18. Interference of the Histone Deacetylase Inhibits Pollen Germination and Pollen Tube Growth in Picea wilsonii Mast.

    PubMed

    Cui, Yaning; Ling, Yu; Zhou, Junhui; Li, Xiaojuan

    2015-01-01

    Histone deacetylase (HDAC) is a crucial component in the regulation of gene expression in various cellular processes in animal and plant cells. HDAC has been reported to play a role in embryogenesis. However, the effect of HDAC on androgamete development remains unclear, especially in gymnosperms. In this study, we used the HDAC inhibitors trichostatin A (TSA) and sodium butyrate (NaB) to examine the role of HDAC in Picea wilsonii pollen germination and pollen tube elongation. Measurements of the tip-focused Ca2+ gradient revealed that TSA and NaB influenced this gradient. Immunofluorescence showed that actin filaments were disrupted into disorganized fragments. As a result, the vesicle trafficking was disturbed, as determined by FM4-64 labeling. Moreover, the distribution of pectins and callose in cell walls was significantly altered in response to TSA and NaB. Our results suggest that HDAC affects pollen germination and polarized pollen tube growth in Picea wilsonii by affecting the intracellular Ca2+ concentration gradient, actin organization patterns, vesicle trafficking, as well as the deposition and configuration of cell wall components.

  19. Histone deacetylase inhibition reduces hypothyroidism-induced neurodevelopmental defects in rats.

    PubMed

    Kumar, Praveen; Mohan, Vishwa; Sinha, Rohit Anthony; Chagtoo, Megha; Godbole, Madan M

    2015-11-01

    Thyroid hormone (TH) through its receptor (TRα/β) influences spatio-temporal regulation of its target gene repertoire during brain development. Though hypothyroidism in WT rodent models of perinatal hypothyroidism severely impairs neurodevelopment, its effect on TRα/β knockout mice is less severe. An explanation to this paradox is attributed to a possible repressive action of unliganded TRs during development. Since unliganded TRs suppress gene expression through the recruitment of histone deacetylase (HDACs) via co-repressor complexes, we tested whether pharmacological inhibition of HDACs may prevent the effects of hypothyroidism on brain development. Using valproate, an HDAC inhibitor, we show that HDAC inhibition significantly blocks the deleterious effects of hypothyroidism on rat cerebellum, evident by recovery of TH target genes like Bdnf, Pcp2 and Mbp as well as improved dendritic structure of cerebellar Purkinje neurons. Together with this, HDAC inhibition also rescues hypothyroidism-induced motor and cognitive defects. This study therefore provides an insight into the role of HDACs in TH insufficiency during neurodevelopment and their inhibition as a possible therapeutics for treatment.

  20. Histone Deacetylase Inhibitors Antagonize Distinct Pathways to Suppress Tumorigenesis of Embryonal Rhabdomyosarcoma

    PubMed Central

    Vleeshouwer-Neumann, Terra; Phelps, Michael; Bammler, Theo K.; MacDonald, James W.; Jenkins, Isaac; Chen, Eleanor Y.

    2015-01-01

    Embryonal rhabdomyosarcoma (ERMS) is the most common soft tissue cancer in children. The prognosis of patients with relapsed or metastatic disease remains poor. ERMS genomes show few recurrent mutations, suggesting that other molecular mechanisms such as epigenetic regulation might play a major role in driving ERMS tumor biology. In this study, we have demonstrated the diverse roles of histone deacetylases (HDACs) in the pathogenesis of ERMS by characterizing effects of HDAC inhibitors, trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA; also known as vorinostat) in vitro and in vivo. TSA and SAHA suppress ERMS tumor growth and progression by inducing myogenic differentiation as well as reducing the self-renewal and migratory capacity of ERMS cells. Differential expression profiling and pathway analysis revealed downregulation of key oncogenic pathways upon HDAC inhibitor treatment. By gain-of-function, loss-of-function, and chromatin immunoprecipitation (ChIP) studies, we show that Notch1- and EphrinB1-mediated pathways are regulated by HDACs to inhibit differentiation and enhance migratory capacity of ERMS cells, respectively. Our study demonstrates that aberrant HDAC activity plays a major role in ERMS pathogenesis. Druggable targets in the molecular pathways affected by HDAC inhibitors represent novel therapeutic options for ERMS patients. PMID:26636678

  1. Interference of the Histone Deacetylase Inhibits Pollen Germination and Pollen Tube Growth in Picea wilsonii Mast

    PubMed Central

    Zhou, Junhui; Li, Xiaojuan

    2015-01-01

    Histone deacetylase (HDAC) is a crucial component in the regulation of gene expression in various cellular processes in animal and plant cells. HDAC has been reported to play a role in embryogenesis. However, the effect of HDAC on androgamete development remains unclear, especially in gymnosperms. In this study, we used the HDAC inhibitors trichostatin A (TSA) and sodium butyrate (NaB) to examine the role of HDAC in Picea wilsonii pollen germination and pollen tube elongation. Measurements of the tip-focused Ca2+ gradient revealed that TSA and NaB influenced this gradient. Immunofluorescence showed that actin filaments were disrupted into disorganized fragments. As a result, the vesicle trafficking was disturbed, as determined by FM4-64 labeling. Moreover, the distribution of pectins and callose in cell walls was significantly altered in response to TSA and NaB. Our results suggest that HDAC affects pollen germination and polarized pollen tube growth in Picea wilsonii by affecting the intracellular Ca2+ concentration gradient, actin organization patterns, vesicle trafficking, as well as the deposition and configuration of cell wall components. PMID:26710276

  2. Pharmacological Selectivity Within Class I Histone Deacetylases Predicts Effects on Synaptic Function and Memory Rescue

    PubMed Central

    Rumbaugh, Gavin; Sillivan, Stephanie E; Ozkan, Emin D; Rojas, Camilo S; Hubbs, Christopher R; Aceti, Massimiliano; Kilgore, Mark; Kudugunti, Shashi; Puthanveettil, Sathyanarayanan V; Sweatt, J David; Rusche, James; Miller, Courtney A

    2015-01-01

    Histone deacetylases (HDACs) are promising therapeutic targets for neurological and psychiatric disorders that impact cognitive ability, but the relationship between various HDAC isoforms and cognitive improvement is poorly understood, particularly in mouse models of memory impairment. A goal shared by many is to develop HDAC inhibitors with increased isoform selectivity in order to reduce unwanted side effects, while retaining procognitive effects. However, studies addressing this tack at the molecular, cellular and behavioral level are limited. Therefore, we interrogated the biological effects of class I HDAC inhibitors with varying selectivity and assessed a subset of these compounds for their ability to regulate transcriptional activity, synaptic function and memory. The HDAC-1, -2, and -3 inhibitors, RGFP963 and RGFP968, were most effective at stimulating synaptogenesis, while the selective HDAC3 inhibitor, RGFP966, with known memory enhancing abilities, had minimal impact. Furthermore, RGFP963 increased hippocampal spine density, while HDAC3 inhibition was ineffective. Genome-wide gene expression analysis by RNA sequencing indicated that RGFP963 and RGFP966 induce largely distinct transcriptional profiles in the dorsal hippocampus of mature mice. The results of bioinformatic analyses were consistent with RGFP963 inducing a transcriptional program that enhances synaptic efficacy. Finally, RGFP963, but not RGFP966, rescued memory in a mouse model of Alzheimer's Disease. Together, these studies suggest that the specific memory promoting properties of class I HDAC inhibitors may depend on isoform selectivity and that certain pathological brain states may be more receptive to HDAC inhibitors that improve network function by enhancing synapse efficacy. PMID:25837283

  3. MicroRNA-1 regulates chondrocyte phenotype by repressing histone deacetylase 4 during growth plate development.

    PubMed

    Li, Pengcui; Wei, Xiaochun; Guan, Yingjie; Chen, Qian; Zhao, Tingcun; Sun, Changqi; Wei, Lei

    2014-09-01

    MicroRNAs (miRs) are noncoding RNAs (17-25 nt) that control translation and/or mRNA degradation. Using Northern blot analysis, we identified that miR-1 is specifically expressed in growth plate cartilage in addition to muscle tissue, but not in brain, intestine, liver, or lung. We obtained the first evidence that miR-1 is highly expressed in the hypertrophic zone of the growth plate, with an 8-fold increase compared with the proliferation zone; this location coincides with the Ihh and Col X expression regions in vivo. MiR-1 significantly induces chondrocyte proliferation and differentiation. We further identified histone deacetylase 4 (HDAC4) as a target of miR-1. HDAC4 negatively regulates chondrocyte hypertrophy by inhibiting Runx2, a critical transcription factor for chondrocyte hypertrophy. MiR-1 inhibits both endogenous HDAC4 protein by 2.2-fold and the activity of a reporter gene bearing the 3'-untranslated region (UTR) of HDAC4 by 3.3-fold. Conversely, knockdown of endogenous miR-1 relieves the repression of HDAC4. Deletion of the miR-1 binding site in HDAC4 3'-UTR or mutated miR-1 abolishes miR-1-mediated inhibition of the reporter gene activity. Overexpression of HDAC4 reverses miR-1 induction of chondrocyte differentiation markers Col X and Ihh. HDAC4 inhibits Runx2 promoter activity in a dosage-dependent manner. Thus, miR-1 plays an important role in the regulation of the chondrocyte phenotype during the growth plate development via direct targeting of HDAC4.

  4. Structures of Metal-Substituted Human Histone Deacetylase 8 Provide Mechanistic Inferences on Biological Function

    SciTech Connect

    Dowling, Daniel P.; Gattis, Samuel G.; Fierke, Carol A.; Christianson, David W.

    2010-08-23

    The metal-dependent histone deacetylases (HDACs) adopt an {alpha}/{beta} protein fold first identified in rat liver arginase. Despite insignificant overall amino acid sequence identity, these enzymes share a strictly conserved metal binding site with divergent metal specificity and stoichiometry. HDAC8, originally thought to be a Zn{sup 2+}-metallohydrolase, exhibits increased activity with Co{sup 2+} and Fe{sup 2+} cofactors based on k{sub cat}/K{sub M} (Gantt, S. L., Gattis, S. G., and Fierke, C. A. (2006) Biochemistry 45, 6170-6178). Here, we report the first X-ray crystal structures of metallo-substituted HDAC8, Co{sup 2+}-HDAC8, D101L Co{sup 2+}-HDAC8, D101L Mn{sup 2+}-HDAC8, and D101L Fe{sup 2+}-HDAC8, each complexed with the inhibitor M344. Metal content of protein samples in solution is confirmed by inductively coupled plasma mass spectrometry. For the crystalline enzymes, peaks in Bijvoet difference Fourier maps calculated from X-ray diffraction data collected near the respective elemental absorption edges confirm metal substitution. Additional solution studies confirm incorporation of Cu{sup 2+}; Fe{sup 3+} and Ni{sup 2+} do not bind under conditions tested. The metal dependence of the substrate K{sub M} values and the K{sub i} values of hydroxamate inhibitors that chelate the active site metal are consistent with substrate-metal coordination in the precatalytic Michaelis complex that enhances catalysis. Additionally, although HDAC8 binds Zn{sup 2+} nearly 106-fold more tightly than Fe{sup 2+}, the affinities for both metal ions are comparable to the readily exchangeable metal concentrations estimated in living cells, suggesting that HDAC8 could bind either or both Fe{sup 2+} or Zn{sup 2+} in vivo.

  5. Class II histone deacetylases are associated with VHL-independent regulation of hypoxia-inducible factor 1 alpha.

    PubMed

    Qian, David Z; Kachhap, Sushant K; Collis, Spencer J; Verheul, Henk M W; Carducci, Michael A; Atadja, Peter; Pili, Roberto

    2006-09-01

    Hypoxia-inducible factor 1 alpha (HIF-1 alpha) plays a critical role in transcriptional gene activation involved in tumor angiogenesis. A novel class of agents, the histone deacetylase (HDAC) inhibitors, has been shown to inhibit tumor angiogenesis and HIF-1 alpha protein expression. However, the molecular mechanism responsible for this inhibition remains to be elucidated. In the current study, we investigated the molecular link between HIF-1 alpha inhibition and HDAC inhibition. Treatment of the VHL-deficient human renal cell carcinoma cell line UMRC2 with the hydroxamic HDAC inhibitor LAQ824 resulted in a dose-dependent inhibition of HIF-1 alpha protein via a VHL-independent mechanism and reduction of HIF-1 alpha transcriptional activity. HIF-1 alpha inhibition by LAQ824 was associated with HIF-1 alpha acetylation and polyubiquitination. HIF-1 alpha immunoprecipitates contained HDAC activity. Then, we tested different classes of HDAC inhibitors with diverse inhibitory activity of class I versus class II HDACs and assessed their capability of targeting HIF-1 alpha. Hydroxamic acid derivatives with known activity against both class I and class II HDACs were effective in inhibiting HIF-1 alpha at low nanomolar concentrations. In contrast, valproic acid and trapoxin were able to inhibit HIF-1 alpha only at concentrations that are effective against class II HDACs. Coimmunoprecipitation studies showed that class II HDAC4 and HDAC6 were associated with HIF-1 alpha protein. Inhibition by small interfering RNA of HDAC4 and HDAC6 reduced HIF-1 alpha protein expression and transcriptional activity. Taken together, these results suggest that class II HDACs are associated with HIF-1 alpha stability and provide a rationale for targeting HIF-1 alpha with HDAC inhibitors against class II isozymes.

  6. Histone Deacetylase Inhibitors Equipped with Estrogen Receptor Modulation Activity

    PubMed Central

    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

    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 ERα and ERβ. 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 (ERα 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

  7. Active, phosphorylated fingolimod inhibits histone deacetylases and facilitates fear extinction memory

    PubMed Central

    Hait, Nitai C; Wise, Laura E; Allegood, Jeremy C; O’Brien, Megan; Avni, Dorit; Reeves, Thomas M; Knapp, Pamela E; Lu, Junyan; Luo, Cheng; Miles, Michael F; Milstien, Sheldon; Lichtman, Aron H; Spiegel, Sarah

    2014-01-01

    FTY720 (fingolimod), an FDA-approved drug for treatment of multiple sclerosis, has beneficial effects in the CNS that are not yet well understood, independent of its effects on immune cell trafficking. We show that FTY720 enters the nucleus, where it is phosphorylated by sphingosine kinase 2 (SphK2), and that nuclear FTY720-P binds and inhibits class I histone deacetylases (HDACs), enhancing specific histone acetylations. FTY720 is also phosphorylated in mice and accumulates in the brain, including the hippocampus, inhibits HDACs and enhances histone acetylation and gene expression programs associated with memory and learning, and rescues memory deficits independently of its immunosuppressive actions. Sphk2−/− mice have lower levels of hippocampal sphingosine-1-phosphate, an endogenous HDAC inhibitor, and reduced histone acetylation, and display deficits in spatial memory and impaired contextual fear extinction. Thus, sphingosine-1-phosphate and SphK2 play specific roles in memory functions and FTY720 may be a useful adjuvant therapy to facilitate extinction of aversive memories. PMID:24859201

  8. Active, phosphorylated fingolimod inhibits histone deacetylases and facilitates fear extinction memory.

    PubMed

    Hait, Nitai C; Wise, Laura E; Allegood, Jeremy C; O'Brien, Megan; Avni, Dorit; Reeves, Thomas M; Knapp, Pamela E; Lu, Junyan; Luo, Cheng; Miles, Michael F; Milstien, Sheldon; Lichtman, Aron H; Spiegel, Sarah

    2014-07-01

    FTY720 (fingolimod), an FDA-approved drug for treatment of multiple sclerosis, has beneficial effects in the CNS that are not yet well understood, independent of its effects on immune cell trafficking. We show that FTY720 enters the nucleus, where it is phosphorylated by sphingosine kinase 2 (SphK2), and that nuclear FTY720-P binds and inhibits class I histone deacetylases (HDACs), enhancing specific histone acetylations. FTY720 is also phosphorylated in mice and accumulates in the brain, including the hippocampus, inhibits HDACs and enhances histone acetylation and gene expression programs associated with memory and learning, and rescues memory deficits independently of its immunosuppressive actions. Sphk2(-/-) mice have lower levels of hippocampal sphingosine-1-phosphate, an endogenous HDAC inhibitor, and reduced histone acetylation, and display deficits in spatial memory and impaired contextual fear extinction. Thus, sphingosine-1-phosphate and SphK2 play specific roles in memory functions and FTY720 may be a useful adjuvant therapy to facilitate extinction of aversive memories.

  9. Crebinostat: a novel cognitive enhancer that inhibits histone deacetylase activity and modulates chromatin-mediated neuroplasticity.

    PubMed

    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

    2013-01-01

    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

  10. Histone deacetylase inhibitors upregulate Rap1GAP and inhibit Rap activity in thyroid tumor cells.

    PubMed

    Dong, Xiaoyun; Korch, Christopher; Meinkoth, Judy L

    2011-06-01

    Increases in Rap activity have been associated with tumor progression. Although activating mutations in Rap have not been described, downregulation of Rap1GAP is frequent in human tumors including thyroid carcinomas. In this study, we explored whether endogenous Rap1GAP expression could be restored to thyroid tumor cells. The effects of deacetylase inhibitors and a demethylating agent, individually and in combination, were examined in four differentiated and six anaplastic thyroid carcinoma (ATC) cell lines. Treatment with the structurally distinct histone deacetylase (HDAC) inhibitors, sodium butyrate and trichostatin A, increased Rap1GAP expression in all the differentiated thyroid carcinoma cell lines and in four of the six ATC cell lines. The demethylating agent, 5-aza-deoxycytidine, restored Rap1GAP expression in one anaplastic cell line and enhanced the effects of HDAC inhibitors in a second anaplastic cell line. Western blotting indicated that Rap2 was highly expressed in human thyroid cancer cells. Importantly, treatment with HDAC inhibitors impaired Rap2 activity in both differentiated and anaplastic tumor cell lines. The mechanism through which Rap activity is repressed appears to entail effects on the expression of multiple Rap regulators, including RapGEFs and RapGAPs. These results suggest that HDAC inhibitors may provide a tractable approach to impair Rap activity in human tumor cells.

  11. Histone Deacetylases 6 and 9 and Sirtuin-1 Control Foxp3+ Regulatory T Cell Function Through Shared and Isotype-Specific Mechanisms

    PubMed Central

    Beier, Ulf H.; Wang, Liqing; Han, Rongxiang; Akimova, Tatiana; Liu, Yujie; Hancock, Wayne W.

    2013-01-01

    Therapeutic targeting of histone/protein deacetylase 6 (HDAC6), HDAC9, or the sirtuin-1 (Sirt1) augments the suppressive functions of regulatory T cells (Tregs) that contain the transcription factor Foxp3. However, it is unclear whether distinct mechanisms are involved or whether combined inhibition of these targets would be more beneficial. We compared the suppressive functions of Tregs from wild-type C57BL/6 mice with those from mice with either global (HDAC6−/−, HDAC9−/−, and HDAC6−/−HDAC9−/−), or conditional (fl-Sirt1/CD4-Cre or fl-Sirt1/Foxp3-Cre) HDAC deletion, as well as treatment with isoform-selective HDAC inhibitors. We found that the heat shock response was important for the improvement of Treg suppressive function mediated by HDAC6 inhibition, but not Sirt1 inhibition. Furthermore, although HDAC6, HDAC9, and Sirt1 all deacetylated Foxp3, each protein had diverse effects on transcription factors controlling Foxp3 gene expression. For example, loss of HDAC9 was associated with stabilization of the acetylation of signal transducer and activator of transcription 5 (STAT5) and of its transcriptional activity. Hence, targeting different HDACs increased Treg function by multiple and additive mechanisms, which indicates the therapeutic potential for combinations of HDAC inhibitors in the management of autoimmunity and organ transplantation. PMID:22715468

  12. How to Distinguish Between the Activity of HDAC1-3 and HDAC6 with Western Blot.

    PubMed

    Beyer, Mandy; Kiweler, Nicole; Mahboobi, Siavosh; Krämer, Oliver H

    2017-01-01

    Histone deacetylases (HDACs) catalyze the deacetylation of lysine residues in their target proteins. This biochemical modification can have profound effects on the functions of these proteins and a dysregulation of HDAC activity contributes to severe diseases, including neoplastic transformation. In the following chapter, we present a strategy that allows to distinguish between the inhibition of the class I HDACs HDAC1, 2, and 3 and of the class IIb HDAC HDAC6. This method is based on Western blot and relies on the detection of hyperacetylated substrates of class I or class IIb HDACs in lysates from cells that were treated with histone deacetylase inhibitors (HDACi).

  13. Regulation of neuronal gene expression and survival by basal NMDA receptor activity: a role for histone deacetylase 4.

    PubMed

    Chen, Yelin; Wang, Yuanyuan; Modrusan, Zora; Sheng, Morgan; Kaminker, Joshua S

    2014-11-12

    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.

  14. Insecticidal activities of histone deacetylase inhibitors against a dipteran parasite of sheep, Lucilia cuprina.

    PubMed

    Bagnall, Neil H; Hines, Barney M; Lucke, Andrew J; Gupta, Praveer K; Reid, Robert C; Fairlie, David P; Kotze, Andrew C

    2017-04-01

    Histone deacetylase inhibitors (HDACi) are being investigated for the control of various human parasites. Here we investigate their potential as insecticides for the control of a major ecto-parasite of sheep, the Australian sheep blowfly, Lucilia cuprina. We assessed the ability of HDACi from various chemical classes to inhibit the development of blowfly larvae in vitro, and to inhibit HDAC activity in nuclear protein extracts prepared from blowfly eggs. The HDACi prodrug romidepsin, a cyclic depsipeptide that forms a thiolate, was the most potent inhibitor of larval growth, with equivalent or greater potency than three commercial blowfly insecticides. Other HDACi with potent activity were hydroxamic acids (trichostatin, CUDC-907, AR-42), a thioester (KD5170), a disulphide (Psammaplin A), and a cyclic tetrapeptide bearing a ketone (apicidin). On the other hand, no insecticidal activity was observed for certain other hydroxamic acids, fatty acids, and the sesquiterpene lactone parthenolide. The structural diversity of the 31 hydroxamic acids examined here revealed some structural requirements for insecticidal activity; for example, among compounds with flexible linear zinc-binding extensions, greater potency was observed in the presence of branched capping groups that likely make multiple interactions with the blowfly HDAC enzymes. The insecticidal activity correlated with inhibition of HDAC activity in blowfly nuclear protein extracts, indicating that the toxicity was most likely due to inhibition of HDAC enzymes in the blowfly larvae. The inhibitor potencies against blowfly larvae are different from inhibition of human HDACs, suggesting some selectivity for human over blowfly HDACs, and a potential for developing compounds with the inverse selectivity. In summary, these novel findings support blowfly HDAC enzymes as new targets for blowfly control, and point to development of HDAC inhibitors as a promising new class of insecticides.

  15. Class IIa histone deacetylases affect neuronal remodeling and functional outcome after stroke.

    PubMed

    Kassis, Haifa; Shehadah, Amjad; Li, Chao; Zhang, Yi; Cui, Yisheng; Roberts, Cynthia; Sadry, Neema; Liu, Xianshuang; Chopp, Michael; Zhang, Zheng Gang

    2016-06-01

    We have previously demonstrated that stroke induces nuclear shuttling of class IIa histone deacetylase 4 (HDAC4). Stroke-induced nuclear shuttling of HDAC4 is positively and significantly correlated with improved indices of neuronal remodeling in the peri-infarct cortex. In this study, using a rat model for middle cerebral artery occlusion (MCAO), we tested the effects of selective inhibition of class IIa HDACs on functional recovery and neuronal remodeling when administered 24hr after stroke. Adult male Wistar rats (n = 15-17/group) were subjected to 2 h MCAO and orally gavaged with MC1568 (a selective class IIa HDAC inhibitor), SAHA (a non-selective HDAC inhibitor), or vehicle-control for 7 days starting 24 h after MCAO. A battery of behavioral tests was performed. Lesion volume measurement and immunohistochemistry were performed 28 days after MCAO. We found that stroke increased total HDAC activity in the ipsilateral hemisphere compared to the contralateral hemisphere. Stroke-increased HDAC activity was significantly decreased by the administration of SAHA as well as by MC1568. However, SAHA significantly improved functional outcome compared to vehicle control, whereas selective class IIa inhibition with MC1568 increased mortality and lesion volume and did not improve functional outcome. In addition, MC1568 decreased microtubule associated protein 2 (MAP2, dendrites), phosphorylated neurofilament heavy chain (pNFH, axons) and myelin basic protein (MBP, myelination) immunoreactivity in the peri-infarct cortex. Quantitative RT-PCR of cortical neurons isolated by laser capture microdissection revealed that MC1568, but not SAHA, downregulated CREB and c-fos expression. Additionally, MC1568 decreased the expression of phosphorylated CREB (active) in neurons. Taken together, these findings demonstrate that selective inhibition of class IIa HDACs impairs neuronal remodeling and neurological outcome. Inactivation of CREB and c-fos by MC1568 likely contributes to

  16. Histone deacetylase inhibitors: Future therapeutics for insulin resistance and type 2 diabetes.

    PubMed

    Sharma, Sorabh; Taliyan, Rajeev

    2016-11-01

    Insulin resistance is a common feature of obesity and predisposes the affected individuals to a variety of pathologies, including type 2 diabetes mellitus (T2DM), dyslipidemias, hypertension, cardiovascular disease etc. Insulin resistance is the primary cause of T2DM and it occurs many years before the disease onset. Although Thiazolidinediones (TZDs) such as rosiglitazone and pioglitazone are outstanding insulin sensitizers and are in clinical use since 1990s, however, their serious side effects such as heart attack and bladder cancer have limited their utilization. Thus, there is an unmet need to identify a new class of drugs with insulin sensitizing activity and minimal side effects. In the recent years, Histone deacetylase (HDAC) has emerged as a new molecular target in the control of insulin resistance and T2DM. The level of histone acetylation/deacetylation has been found to be altered during insulin resistance and T2DM conditions. HDAC inhibitors have been found to effectively manage insulin resistance and T2DM in various preclinical models and clinical trials. In this review we will focus on various aspects related to regulation of insulin signalling by HDACs and the future scope of HDAC inhibitors as therapeutics for insulin resistance.

  17. A Photoactivatable Platinum(IV) Complex Targeting Genomic DNA and Histone Deacetylases.

    PubMed

    Kasparkova, Jana; Kostrhunova, Hana; Novakova, Olga; Křikavová, Radka; Vančo, Ján; Trávníček, Zdeněk; Brabec, Viktor

    2015-11-23

    We report toxic effects of a photoactivatable platinum(IV) complex conjugated with suberoyl-bis-hydroxamic acid in tumor cells. The conjugate exerts, after photoactivation, two functions: activity as both a platinum(II) anticancer drug and histone deacetylase (HDAC) inhibitor in cancer cells. This approach relies on the use of a Pt(IV) pro-drug, acting by two independent mechanisms of biological action in a cooperative manner, which can be selectively photoactivated to a cytotoxic species in and around a tumor, thereby increasing selectivity towards cancer cells. These results suggest that this strategy is a valuable route to design new platinum agents with higher efficacy for photodynamic anticancer chemotherapy.

  18. 1,3,4-Oxadiazole-containing histone deacetylase inhibitors: anticancer activities in cancer cells.

    PubMed

    Valente, Sergio; Trisciuoglio, Daniela; De Luca, Teresa; Nebbioso, Angela; Labella, Donatella; Lenoci, Alessia; Bigogno, Chiara; Dondio, Giulio; Miceli, Marco; Brosch, Gerald; Del Bufalo, Donatella; Altucci, Lucia; Mai, Antonello

    2014-07-24

    We describe 1,3,4-oxadiazole-containing hydroxamates (2) and 2-aminoanilides (3) as histone deacetylase inhibitors. Among them, 2t, 2x, and 3i were the most potent and selective against HDAC1. In U937 leukemia cells, 2t was more potent than SAHA in inducing apoptosis, and 3i displayed cell differentiation with a potency similar to MS-275. In several acute myeloid leukemia (AML) cell lines, as well as in U937 cells in combination with doxorubicin, 3i showed higher antiproliferative effects than SAHA.

  19. An apicomplexan ankyrin-repeat histone deacetylase with relatives in photosynthetic eukaryotes.

    PubMed

    Rider, S Dean; Zhu, Guan

    2009-06-01

    Cryptosporidium parvum is a member of the Apicomplexa that lacks a plastid and associated nuclear-encoded genes, which has hampered its use in evolutionary comparisons with algae and eliminated a pool of potentially useful drug targets. Here we show that apicomplexan parasites possess an unusual family of class II histone deacetylase (HDAC) proteins with orthologues that are present in other chromalveolates and primitive algae. A striking feature of these HDAC proteins is the presence of ankyrin repeats in the amino-terminus that appear to be required for enzyme activity. In vitro and in vivo analyses of the C. parvum orthologue indicate that this subclass of chromatin-remodelling proteins is targeted by the anti-cancer drug suberoylanilide hydroxamic acid and that these proteins are most likely involved in the essential process of H4 histone deacetylation that coincides with DNA replication. We propose that members of this novel class of histone deacetylase can serve as promising new targets for treatments against debilitating diseases such as cryptosporidosis, toxoplasmosis and malaria.

  20. Association of valproate-induced teratogenesis with histone deacetylase inhibition in vivo.

    PubMed

    Gurvich, Nadia; Berman, Melissa G; Wittner, Ben S; Gentleman, Robert C; Klein, Peter S; Green, Jeremy B A

    2005-07-01

    Chemically induced birth defects are an important public health and human problem. Here we use Xenopus and zebrafish as models to investigate the mechanism of action of a well-known teratogen, valproic acid (VPA). VPA is a drug used in treatment of epilepsy and bipolar disorder but causes spina bifida if taken during pregnancy. VPA has several biochemical activities, including inhibition of histone deacetylases (HDACs). To investigate the mechanism of action of VPA, we compared its effects in Xenopus and zebrafish embryos with those of known HDAC inhibitors and noninhibitory VPA analogs. We found that VPA and other HDAC inhibitors cause very similar and characteristic developmental defects whereas VPA analogs with poor inhibitory activity in vivo have little teratogenic effect. Unbiased microarray analysis revealed that the effects of VPA and trichostatin A (TSA), a structurally unrelated HDAC inhibitor, are strikingly concordant. The concordance is apparent both by en masse correlation of fold-changes and by detailed similarity of dose-response profiles of individual genes. Together, the results demonstrate that the teratogenic effects of VPA are very likely mediated specifically by inhibition of HDACs.

  1. The tobacco smoke component acrolein induces glucocorticoid resistant gene expression via inhibition of histone deacetylase

    PubMed Central

    Randall, Matthew J.; Haenen, Guido R.M.M.; Bouwman, Freek G.; van der Vliet, Albert; Bast, Aalt

    2016-01-01

    Chronic obstructive pulmonary disease (COPD) is the leading cause of cigarette smoke-related death worldwide. Acrolein, a crucial reactive electrophile found in cigarette smoke mimics many of the toxic effects of cigarette smoke-exposure in the lung. In macrophages, cigarette smoke is known to hinder histone deacetylases (HDACs), glucocorticoid-regulated enzymes that play an important role in the pathogenesis of glucocorticoid resistant inflammation, a common feature of COPD. Thus, we hypothesize that acrolein plays a role in COPD-associated glucocorticoid resistance. To examine the role of acrolein on glucocorticoid resistance, U937 monocytes, differentiated with PMA to macrophage-like cells were treated with acrolein for 0.5 h followed by stimulation with hydrocortisone for 8 h, or treated simultaneously with LPS and hydrocortisone for 8 h without acrolein. GSH and nuclear HDAC activity were measured, or gene expression was analyzed by qPCR. Acrolein-mediated TNFα gene expression was not suppressed by hydrocortisone whereas LPS-induced TNFα expression was suppressed. Acrolein also significantly inhibited nuclear HDAC activity in macrophage-like cells. Incubation of recombinant HDAC2 with acrolein led to the formation of an HDAC2-acrolein adduct identified by mass spectrometry. Therefore, these results suggest that acrolein-induced inflammatory gene expression is resistant to suppression by the endogenous glucocorticoid, hydrocortisone. PMID:26481333

  2. Histone Deacetylase 4 promotes cholestatic liver injury in the absence of Prohibitin-1

    PubMed Central

    Barbier-Torres, Lucía; Beraza, Naiara; Fernández-Tussy, Pablo; Lopitz-Otsoa, Fernando; Fernández-Ramos, David; Zubiete-Franco, Imanol; Varela-Rey, Marta; Delgado, Teresa C; Gutiérrez, Virginia; Anguita, Juan; Pares, Albert; Banales, Jesús M; Villa, Erica; Caballería, Juan; Alvarez, Luis; Lu, Shelly C; Mato, Jose M; Martínez-Chantar, María Luz

    2015-01-01

    Prohibitin 1 (PHB1) is an evolutionary conserved pleiotropic protein that participates in diverse processes depending on its subcellular localization and interactome. Recent data have indicated a diverse role for PHB1 in the pathogenesis of obesity, cancer and inflammatory bowel disease, among others. Data presented here suggest that PHB1 is also linked to cholestatic liver disease. PHB1 expression is markedly reduced in patients with primary billiary cirrhosis and biliary atresia and Alagille syndrome, two major pediatric cholestatic conditions. In the experimental model of bile duct ligation, silencing of PHB1 induced liver fibrosis, reduced animal survival and induced bile duct proliferation. Importantly, the modulatory effect of PHB1 is not dependent on its known mitochondrial function. Importantly, d PHB1 interacts with Histone Deacetylase 4 (HDAC4) in the presence of bile acids. Hence, PHB1 depletion leads to increased nuclear HDAC4 content and its associated epigenetic changes. Remarkably, HDAC4 silencing and the administration of the HDAC inhibitor parthenolide during obstructive cholestasis in vivo promote genomic reprogramming leading to the regression of the fibrotic phenotype in the liver-specific Phb1 KO mice. Conclusion Our data identify PHB1 as an important mediator of cholestatic liver injury regulating the activity of HDAC4, which controls specific epigenetic marks. These results identify potential novel strategies to treat liver injury and fibrosis, particularly as a consequence of chronic cholestasis. PMID:26109312

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

    SciTech Connect

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

    2012-07-11

    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.

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

    SciTech Connect

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

    2011-12-31

    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.

  5. The tobacco smoke component acrolein induces glucocorticoid resistant gene expression via inhibition of histone deacetylase.

    PubMed

    Randall, Matthew J; Haenen, Guido R M M; Bouwman, Freek G; van der Vliet, Albert; Bast, Aalt

    2016-01-05

    Chronic obstructive pulmonary disease (COPD) is the leading cause of cigarette smoke-related death worldwide. Acrolein, a crucial reactive electrophile found in cigarette smoke mimics many of the toxic effects of cigarette smoke-exposure in the lung. In macrophages, cigarette smoke is known to hinder histone deacetylases (HDACs), glucocorticoid-regulated enzymes that play an important role in the pathogenesis of glucocorticoid resistant inflammation, a common feature of COPD. Thus, we hypothesize that acrolein plays a role in COPD-associated glucocorticoid resistance. To examine the role of acrolein on glucocorticoid resistance, U937 monocytes, differentiated with PMA to macrophage-like cells were treated with acrolein for 0.5h followed by stimulation with hydrocortisone for 8h, or treated simultaneously with LPS and hydrocortisone for 8h without acrolein. GSH and nuclear HDAC activity were measured, or gene expression was analyzed by qPCR. Acrolein-mediated TNFα gene expression was not suppressed by hydrocortisone whereas LPS-induced TNFα expression was suppressed. Acrolein also significantly inhibited nuclear HDAC activity in macrophage-like cells. Incubation of recombinant HDAC2 with acrolein led to the formation of an HDAC2-acrolein adduct identified by mass spectrometry. Therefore, these results suggest that acrolein-induced inflammatory gene expression is resistant to suppression by the endogenous glucocorticoid, hydrocortisone.

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

    SciTech Connect

    Sriwilaijaroen, N.; Boonma, S.; Attasart, P.; Pothikasikorn, J.; Panyim, S.; Noonpakdee, W.

    2009-04-03

    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.

  7. Histone deacetylase inhibitors decrease Toll-like receptor-mediated activation of proinflammatory gene expression by impairing transcription factor recruitment

    PubMed Central

    Bode, Konrad A; Schroder, Kate; Hume, David A; Ravasi, Timothy; Heeg, Klaus; Sweet, Matthew J; Dalpke, Alexander H

    2007-01-01

    Post-translational modifications of histone proteins are major mechanisms that modify chromatin structure and regulate gene expression in eukaryotes. Activation of histone acetyltransferases or inhibition of histone deacetylases (HDACs) is generally believed to allow chromatin to assume a more open state, permitting transcriptional activity. We report here the surprising observation that treatment of murine dendritic cells with the HDAC inhibitors trichostatin A (TSA) or suberoylanilide hydroxamic acid (SAHA) in non-apoptotic concentrations strongly inhibited induction of both interleukin-12 protein p40 (IL-12p40) mRNA and protein upon stimulation of Toll-like receptors (TLRs). Moreover, TLR-mediated up-regulation of costimulatory molecules was also inhibited. Up-regulation of tumour necrosis factor-α mRNA and protein in response to TLR agonists was only affected upon prolonged exposure to HDAC inhibitors and regulation of IL-1β was not affected. Similar effects were apparent in murine and human macrophages. Regarding the mode of action, HDAC inhibition increased the acetylation status at the IL-12p40 locus. Nevertheless, IL-12p40 chromatin remodelling, binding of Rel-A and IRF1 to the IL-12p40 promoter and transcriptional activation were abrogated. In contrast, HDAC inhibitors had no effects on upstream nuclear factor-κB and mitogen-activated protein kinase activation. Thus HDACs positively regulate the expression of a subset of cytokine genes by enabling transcription factor recruitment. PMID:17635610

  8. Piceatannol Attenuates Renal Fibrosis Induced by Unilateral Ureteral Obstruction via Downregulation of Histone Deacetylase 4/5 or p38-MAPK Signaling

    PubMed Central

    Choi, Sin Young; Piao, Zhe Hao; Jin, Li; Kim, Jung Ha; Kim, Gwi Ran; Ryu, Yuhee; Lin, Ming Quan; Kim, Hyung-Seok; Kee, Hae Jin; Jeong, Myung Ho

    2016-01-01

    Piceatannol, a resveratrol metabolite, is a phenolic compound found in red wine and grapes. We investigated the effect of piceatannol on renal fibrosis and histone deacetylase (HDAC) expression in a mouse model of unilateral ureteral obstruction (UUO). Fibrosis was established by UUO and piceatannol was intraperitoneally injected for 2 weeks. Piceatannol suppressed extracellular matrix (ECM) protein deposition including collagen type I and fibronectin as well as connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA) in UUO kidneys. However, the expressions of epithelial-mesenchymal transition (EMT) marker genes, such as N-cadherin and E-cadherin, were not changed in the kidneys after UUO. Masson’s trichrome staining and fluorescence immunostaining showed that piceatannol administration attenuated collagen deposition in UUO kidneys. HDAC1, HDAC4, HDAC5, HDAC6, and HDAC10 protein expression was upregulated in UUO kidneys, whereas that of HDAC8 was downregulated. Piceatannol treatment significantly reduced HDAC4 and HDAC5 protein expression. Further, piceatannol attenuated phosphorylation of p38 mitogen-activated protein kinase (p38-MAPK) in UUO kidneys, but not that of transforming growth factor beta1-Smad2/3. These results suggest that class I HDACs and class IIa/b HDACs are involved in renal fibrosis development. Piceatannol may be a beneficial therapeutic agent for treating renal fibrosis via reduction of HDAC4 and HDAC5 protein expression or suppression of the p38-MAPK signaling pathway. PMID:27902771

  9. Exploring inhibitor release pathways in histone deacetylases using random acceleration molecular dynamics simulations.

    PubMed

    Kalyaanamoorthy, Subha; Chen, Yi-Ping Phoebe

    2012-02-27

    Molecular channel exploration perseveres to be the prominent solution for eliciting structure and accessibility of active site and other internal spaces of macromolecules. The volume and silhouette characterization of these channels provides answers for the issues of substrate access and ligand swapping between the obscured active site and the exterior of the protein. Histone deacetylases (HDACs) are metal-dependent enzymes that are involved in the cell growth, cell cycle regulation, and progression, and their deregulations have been linked with different types of cancers. Hence HDACs, especially the class I family, are widely recognized as the important cancer targets, and the characterizations of their structures and functions have been of special interest in cancer drug discovery. The class I HDACs are known to possess two different protein channels, an 11 Å and a 14 Å (named channels A and B1, respectively), of which the former is a ligand or substrate occupying tunnel that leads to the buried active site zinc ion and the latter is speculated to be involved in product release. In this work, we have carried out random acceleration molecular dynamics (RAMD) simulations coupled with the classical molecular dynamics to explore the release of the ligand, N-(2-aminophenyl) benzamide (LLX) from the active sites of the recently solved X-ray crystal structure of HDAC2 and the computationally modeled HDAC1 proteins. The RAMD simulations identified significant structural and dynamic features of the HDAC channels, especially the key 'gate-keeping' amino acid residues that control these channels and the ligand release events. Further, this study identified a novel and unique channel B2, a subchannel from channel B1, in the HDAC1 protein structure. The roles of water molecules in the LLX release from the HDAC1 and HDAC2 enzymes are also discussed. Such structural and dynamic properties of the HDAC protein channels that govern the ligand escape reactions will provide

  10. A Class 1 Histone Deacetylase with Potential as an Antifungal Target

    PubMed Central

    Bauer, Ingo; Varadarajan, Divyavaradhi; Pidroni, Angelo; Gross, Silke; Vergeiner, Stefan; Faber, Birgit; Hermann, Martin; Tribus, Martin; Brosch, Gerald

    2016-01-01

    ABSTRACT Histone deacetylases (HDACs) remove acetyl moieties from lysine residues at histone tails and nuclear regulatory proteins and thus significantly impact chromatin remodeling and transcriptional regulation in eukaryotes. In recent years, HDACs of filamentous fungi were found to be decisive regulators of genes involved in pathogenicity and the production of important fungal metabolites such as antibiotics and toxins. Here we present proof that one of these enzymes, the class 1 type HDAC RpdA, is of vital importance for the opportunistic human pathogen Aspergillus fumigatus. Recombinant expression of inactivated RpdA shows that loss of catalytic activity is responsible for the lethal phenotype of Aspergillus RpdA null mutants. Furthermore, we demonstrate that a fungus-specific C-terminal region of only a few acidic amino acids is required for both the nuclear localization and catalytic activity of the enzyme in the model organism Aspergillus nidulans. Since strains with single or multiple deletions of other classical HDACs revealed no or only moderate growth deficiencies, it is highly probable that the significant delay of germination and the growth defects observed in strains growing under the HDAC inhibitor trichostatin A are caused primarily by inhibition of catalytic RpdA activity. Indeed, even at low nanomolar concentrations of the inhibitor, the catalytic activity of purified RpdA is considerably diminished. Considering these results, RpdA with its fungus-specific motif represents a promising target for novel HDAC inhibitors that, in addition to their increasing impact as anticancer drugs, might gain in importance as antifungals against life-threatening invasive infections, apart from or in combination with classical antifungal therapy regimes. PMID:27803184

  11. Kaempferol, a new nutrition-derived pan-inhibitor of human histone deacetylases.

    PubMed

    Berger, Alexander; Venturelli, Sascha; Kallnischkies, Mascha; Böcker, Alexander; Busch, Christian; Weiland, Timo; Noor, Seema; Leischner, Christian; Weiss, Thomas S; Lauer, Ulrich M; Bischoff, Stephan C; Bitzer, Michael

    2013-06-01

    Kaempferol is a natural polyphenol belonging to the group of flavonoids. Different biological functions like inhibition of oxidative stress in plants or animal cells and apoptosis induction have been directly associated with kaempferol. The underlying mechanisms are only partially understood. Here we report for the first time that kaempferol has a distinct epigenetic activity by inhibition of histone deacetylases (HDACs). In silico docking analysis revealed that it fits into the binding pocket of HDAC2, 4, 7 or 8 and thereby binds to the zinc ion of the catalytic center. Further in vitro profiling of all conserved human HDACs of class I, II and IV showed that kaempferol inhibited all tested HDACs. In clinical oncology, HDAC inhibitors are currently under investigation as new anticancer compounds. Therefore, we studied the effect of kaempferol on human-derived hepatoma cell lines HepG2 and Hep3B as well as on HCT-116 colon cancer cells and found that it induces hyperacetylation of histone complex H3. Furthermore, kaempferol mediated a prominent reduction of cell viability and proliferation rate. Interestingly, toxicity assays revealed signs of relevant cellular toxicity in primary human hepatocytes only starting at 50 μM as well as in an in vivo chicken embryotoxicity assay at 200 μM. In conclusion, the identification of a novel broad inhibitory capacity of the natural compound kaempferol for human-derived HDAC enzymes opens up the perspective for clinical application in both tumor prevention and therapy. Moreover, kaempferol may serve as a novel lead structure for chemical optimization of pharmacokinetics, pharmacology or inhibitory activities.

  12. Delaying histone deacetylase response to injury accelerates conversion into repair Schwann cells and nerve regeneration

    PubMed Central

    Brügger, Valérie; Duman, Mert; Bochud, Maëlle; Münger, Emmanuelle; Heller, Manfred; Ruff, Sophie; Jacob, Claire

    2017-01-01

    The peripheral nervous system (PNS) regenerates after injury. However, regeneration is often compromised in the case of large lesions, and the speed of axon reconnection to their target is critical for successful functional recovery. After injury, mature Schwann cells (SCs) convert into repair cells that foster axonal regrowth, and redifferentiate to rebuild myelin. These processes require the regulation of several transcription factors, but the driving mechanisms remain partially understood. Here we identify an early response to nerve injury controlled by histone deacetylase 2 (HDAC2), which coordinates the action of other chromatin-remodelling enzymes to induce the upregulation of Oct6, a key transcription factor for SC development. Inactivating this mechanism using mouse genetics allows earlier conversion into repair cells and leads to faster axonal regrowth, but impairs remyelination. Consistently, short-term HDAC1/2 inhibitor treatment early after lesion accelerates functional recovery and enhances regeneration, thereby identifying a new therapeutic strategy to improve PNS regeneration after lesion. PMID:28139683

  13. Benzothiazole-containing hydroxamic acids as histone deacetylase inhibitors and antitumor agents.

    PubMed

    Oanh, Dao Thi Kim; Hai, Hoang Van; Park, Sang Ho; Kim, Hyun-Jung; Han, Byung-Woo; Kim, Hyung-Sook; Hong, Jin-Tae; Han, Sang-Bae; Hue, Van Thi My; Nam, Nguyen-Hai

    2011-12-15

    Data from clinical studies indicate that inhibitors of Class I and Class II histone deacetylase (HDAC) enzymes show great promise for the treatment of cancer. Zolinza (SAHA, Zolinza) was recently approved by the FDA for the treatment of the cutaneous manifestations of cutaneous T-cell lymphoma. As a part of our ongoing effort to identify novel small molecules to target these important enzymes, we have prepared two series of benzothiazole-containing analogues of SAHA. It was found that several compounds with 6C-bridge linking benzothiazole moiety and hydroxamic functional groups showed good inhibition against HDAC3 and 4 at as low as 1 μg/ml and exhibited potent cytotoxicity against five cancer cell lines with average IC(50) values of as low as 0.81 μg/ml, almost equipotent to SAHA.

  14. PC4 Coactivates MyoD by Relieving the Histone Deacetylase 4-Mediated Inhibition of Myocyte Enhancer Factor 2C

    PubMed Central

    Micheli, Laura; Leonardi, Luca; Conti, Filippo; Buanne, Pasquale; Canu, Nadia; Caruso, Maurizia; Tirone, Felice

    2005-01-01

    Histone deacetylase 4 (HDAC4) negatively regulates skeletal myogenesis by associating with the myocyte enhancer factor 2 (MEF2) transcription factors. Our data indicate that the gene PC4 (interferon-related developmental regulator 1 [IFRD1], Tis7), which we have previously shown to be required for myoblast differentiation, is both induced by MyoD and potentiates the transcriptional activity of MyoD, thus revealing a positive regulatory loop between these molecules. Enhancement by PC4 of MyoD-dependent activation of muscle gene promoters occurs selectively through MEF2 binding sites. Furthermore, PC4 localizes in the nucleus of differentiating myoblasts, associates with MEF2C, and is able to counteract the HDAC4-mediated inhibition of MEF2C. This latter action can be explained by the observed ability of PC4 to dose dependently displace HDAC4 from MEF2C. Consistently, we have observed that (i) the region of PC4 that binds MEF2C is sufficient to counteract the inhibition by HDAC4; (ii) PC4, although able to bind HDAC4, does not inhibit the enzymatic activity of HDAC4; and (iii) PC4 overcomes the inhibition mediated by the amino-terminal domain of HDAC4, which associates with MEF2C but not with PC4. Together, our findings strongly suggest that PC4 acts as a coactivator of MyoD and MEF2C by removing the inhibitory effect of HDAC4, thus exerting a pivotal function during myogenesis. PMID:15743821

  15. Plant Polyphenols and Oxidative Metabolites of the Herbal Alkenylbenzene Methyleugenol Suppress Histone Deacetylase Activity in Human Colon Carcinoma Cells

    PubMed Central

    Groh, Isabel Anna Maria; Chen, Chen; Lüske, Claudia; Cartus, Alexander Thomas; Esselen, Melanie

    2013-01-01

    Evidence has been provided that diet and environmental factors directly influence epigenetic mechanisms associated with cancer development in humans. The inhibition of histone deacetylase (HDAC) activity and the disruption of the HDAC complex have been recognized as a potent strategy for cancer therapy and chemoprevention. In the present study, we investigated whether selected plant constituents affect HDAC activity or HDAC1 protein status in the human colon carcinoma cell line HT29. The polyphenols (−)-epigallocatechin-3-gallate (EGCG) and genistein (GEN) as well as two oxidative methyleugenol (ME) metabolites were shown to inhibit HDAC activity in intact HT29 cells. Concomitantly, a significant decrease of the HDAC1 protein level was observed after incubation with EGCG and GEN, whereas the investigated ME metabolites did not affect HDAC1 protein status. In conclusion, dietary compounds were found to possess promising HDAC-inhibitory properties, contributing to epigenetic alterations in colon tumor cells, which should be taken into account in further risk/benefit assessments of polyphenols and alkenylbenzenes. PMID:23476753

  16. Image-Guided Synthesis Reveals Potent Blood-Brain Barrier Permeable Histone Deacetylase Inhibitors

    PubMed Central

    2014-01-01

    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

  17. Fluorescent Probes for Single-Step Detection and Proteomic Profiling of Histone Deacetylases.

    PubMed

    Xie, Yusheng; Ge, Jingyan; Lei, Haipeng; Peng, Bo; Zhang, Huatang; Wang, Danyang; Pan, Sijun; Chen, Ganchao; Chen, Lanfang; Wang, Yi; Hao, Quan; Yao, Shao Q; Sun, Hongyan

    2016-12-07

    Histone deacetylases (HDACs) play important roles in regulating various physiological and pathological processes. Developing fluorescent probes capable of detecting HDAC activity can help further elucidate the roles of HDACs in biology. In this study, we first developed a set of activity-based fluorescent probes by incorporating the Kac residue and the O-NBD group. Upon enzymatic removal of the acetyl group in the Kac residue, the released free amine reacted intramolecularly with the O-NBD moiety, resulting in turn-on fluorescence. These designed probes are capable of detecting HDAC activity in a continuous fashion, thereby eliminating the extra step of fluorescence development. Remarkably, the amount of turn-on fluorescence can be as high as 50-fold, which is superior to the existing one-step HDAC fluorescent probes. Inhibition experiments further proved that the probes can serve as useful tools for screening HDAC inhibitors. Building on these results, we moved on and designed a dual-purpose fluorescent probe by introducing a diazirine photo-cross-linker into the probe. The resulting probe was not only capable of reporting enzymatic activity but also able to directly identify and capture the protein targets from the complex cellular environment. By combining a fluorometric method and in-gel fluorescence scanning technique, we found that epigenetic readers and erasers can be readily identified and differentiated using a single probe. This is not achievable with traditional photoaffinity probes. In light of the prominent properties and the diverse functions of this newly developed probe, we envision that it can provide a robust tool for functional analysis of HDACs and facilitate future drug discovery in epigenetics.

  18. Cyclic phosphatidic acid inhibits alkyl-glycerophosphate-induced downregulation of histone deacetylase 2 expression and suppresses the inflammatory response in human coronary artery endothelial cells.

    PubMed

    Tsukahara, Tamotsu; Haniu, Hisao; Matsuda, Yoshikazu

    2014-01-01

    Activation of the endothelium by alkyl-glycerophosphate (AGP) has been implicated in the development of atherosclerosis. Our previous study suggested that cyclic phosphatidic acid (cPA) inhibits arterial wall remodeling in a rat model in vivo. However, the mechanisms through which specific target genes are regulated during this process remain unclear. Here, we examined whether cPA inhibited AGP-induced expression of class I histone deacetylases (HDACs, namely HDAC1, HDAC2, HDAC3, and HDAC8), which may affect subsequent transcriptional activity of target genes. Our experimental results showed that human coronary artery endothelial cells (HCAECs) expressed high levels of HDAC2 and low levels HDAC1, HDAC3, and HDAC8. Moreover, AGP treatment induced downregulation of HDAC2 expression in HCAECs. However, cotreatment with cPA inhibited this downregulation of HDAC2 expression. Interestingly, treatment with AGP increased the expression and secretion of endogenous interleukin (IL)-6 and IL-8; however, this effect was inhibited when HCAECs were cotreated with cPA or the synthetic peroxisome proliferator-activator receptor gamma (PPARγ) antagonist T0070907. Thus, our data suggested that cPA may have beneficial effects in inflammation-related cardiovascular disease by controlling HDAC2 regulation.

  19. Functional differences in epigenetic modulators-superiority of mercaptoacetamide-based histone deacetylase inhibitors relative to hydroxamates in cortical neuron neuroprotection studies.

    PubMed

    Kozikowski, Alan P; Chen, Yufeng; Gaysin, Arsen; Chen, Bin; D'Annibale, Melissa A; Suto, Carla M; Langley, Brett C

    2007-06-28

    We compare the ability of two structurally different classes of epigenetic modulators, namely, histone deacetylase (HDAC) inhibitors containing either a hydroxamate or a mercaptoacetamide as the zinc binding group, to protect cortical neurons in culture from oxidative stress-induced death. This study reveals that some of the mercaptoacetamide-based HDAC inhibitors are fully protective, whereas the hydroxamates show toxicity at higher concentrations. Our present results appear to be consistent with the possibility that the mercaptoacetamide-based HDAC inhibitors interact with a different subset of the HDAC isozymes [less activity at HDAC1 and 2 correlates with less inhibitor toxicity], or alternatively, are interacting selectively with only the cytoplasmic HDACs that are crucial for protection from oxidative stress.

  20. Droxinostat, a Histone Deacetylase Inhibitor, Induces Apoptosis in Hepatocellular Carcinoma Cell Lines via Activation of the Mitochondrial Pathway and Downregulation of FLIP1

    PubMed Central

    Liu, Jing; Li, Guangming; Wang, Xiang; Wang, Liang; Zhao, Rui; Wang, Juanxia; Kong, Yin; Ding, Jie; Li, Juan; Zhang, Lingyi

    2016-01-01

    Background: The current chemotherapeutic outcomes for hepatocellular carcinoma (HCC) are not encouraging, and long-term survival of this patient group remains poor. Recent studies have demonstrated the utility of histone deacetylase inhibitors that can disrupt cell proliferation and survival in HCC management. However, the effects of droxinostat, a type of histone deacetylase inhibitor, on HCC remain to be established. Methods: The effects of droxinostat on HCC cell lines SMMC-7721 and HepG2 were investigated. Histone acetylation and apoptosis-modulating proteins were assessed via Western blot. Proliferation was examined with 3-(4, 5 dimetyl-2-thiazolyl)-2, 5-diphenyl 2H-tetrazolium bromide, cell proliferation, and real-time cell viability assays, and apoptosis with flow cytometry. Results: Droxinostat inhibited proliferation and colony formation of the HCC cell lines examined. Hepatoma cell death was induced through activation of the mitochondrial apoptotic pathway and downregulation of FLIP expression. Droxinostat suppressed histone deacetylase (HDAC) 3 expression and promoted acetylation of histones H3 and H4. Knockdown of HDAC3 induced hepatoma cell apoptosis and histone H3 and H4 acetylation. Conclusions: Droxinostat suppresses HDAC3 expression and induces histone acetylation and HCC cell death through activation of the mitochondrial apoptotic pathway and downregulation of FLIP, supporting its potential application in the treatment of HCC. PMID:26947884

  1. Analysis of the interplay between all-trans retinoic acid and histone deacetylase inhibitors in leukemic cells.

    PubMed

    Noack, Katrin; Mahendrarajah, Nisintha; Hennig, Dorle; Schmidt, Luisa; Grebien, Florian; Hildebrand, Dagmar; Christmann, Markus; Kaina, Bernd; Sellmer, Andreas; Mahboobi, Siavosh; Kubatzky, Katharina; Heinzel, Thorsten; Krämer, Oliver H

    2016-11-02

    The treatment of acute promyelocytic leukemia (APL) with all-trans retinoic acid (ATRA) induces granulocytic differentiation. This process renders APL cells resistant to cytotoxic chemotherapies. Epigenetic regulators of the histone deacetylases (HDACs) family, which comprise four classes (I-IV), critically control the development and progression of APL. We set out to clarify the parameters that determine the interaction between ATRA and histone deacetylase inhibitors (HDACi). Our assays included drugs against class I HDACs (MS-275, VPA, and FK228), pan-HDACi (LBH589, SAHA), and the novel HDAC6-selective compound Marbostat-100. We demonstrate that ATRA protects APL cells from cytotoxic effects of SAHA, MS-275, and Marbostat-100. However, LBH589 and FK228, which have a superior substrate-inhibitor dissociation constant (Ki) for the class I deacetylases HDAC1, 2, 3, are resistant against ATRA-dependent cytoprotective effects. We further show that HDACi evoke DNA damage, measured as induction of phosphorylated histone H2AX and by the comet assay. The ability of ATRA to protect APL cells from the induction of p-H2AX by HDACi is a readout for the cytoprotective effects of ATRA. Moreover, ATRA increases the fraction of cells in the G1 phase, together with an accumulation of the cyclin-dependent kinase inhibitor p21 and a reduced expression of thymidylate synthase (TdS). In contrast, the ATRA-dependent activation of the transcription factors STAT1, NF-κB, and C/EBP hardly influences the responses of APL cells to HDACi. We conclude that the affinity of HDACi for class I HDACs determines whether such drugs can kill naïve and maturated APL cells.

  2. Nuclear levels and patterns of histone H3 modification and HP1 proteins after inhibition of histone deacetylases.

    PubMed

    Bártová, Eva; Pacherník, Jirí; Harnicarová, Andrea; Kovarík, Ales; Kovaríková, Martina; Hofmanová, Jirina; Skalníková, Magdalena; Kozubek, Michal; Kozubek, Stanislav

    2005-11-01

    The effects of the histone deacetylase inhibitors (HDACi) trichostatin A (TSA) and sodium butyrate (NaBt) were studied in A549, HT29 and FHC human cell lines. Global histone hyperacetylation, leading to decondensation of interphase chromatin, was characterized by an increase in H3(K9) and H3(K4) dimethylation and H3(K9) acetylation. The levels of all isoforms of heterochromatin protein, HP1, were reduced after HDAC inhibition. The observed changes in the protein levels were accompanied by changes in their interphase patterns. In control cells, H3(K9) acetylation and H3(K4) dimethylation were substantially reduced to a thin layer at the nuclear periphery, whereas TSA and NaBt caused the peripheral regions to become intensely acetylated at H3(K9) and dimethylated at H3(K4). The dispersed pattern of H3(K9) dimethylation was stable even at the nuclear periphery of HDACi-treated cells. After TSA and NaBt treatment, the HP1 proteins were repositioned more internally in the nucleus, being closely associated with interchromatin compartments, while centromeric heterochromatin was relocated closer to the nuclear periphery. These findings strongly suggest dissociation of HP1 proteins from peripherally located centromeres in a hyperacetylated and H3(K4) dimethylated environment. We conclude that inhibition of histone deacetylases caused dynamic reorganization of chromatin in parallel with changes in its epigenetic modifications.

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

    PubMed

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

    2008-08-15

    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 vitro and acted as a prodrug, requiring reduction for activity. Spiruchostatin A was a potent (low nM) inhibitor of the growth of various cancer cell lines. Spiruchostatin A-induced acetylation of specific lysine residues within histones H3 and H4, and increased the expression of p21(cip1/waf1), but did not induce acetylation of alpha-tubulin. Spiruchostatin A also induced cell cycle arrest, differentiation and cell death in MCF7 breast cancer cells. Like FK228, spiruchostatin A was both an inducer and substrate of the ABCB1 drug efflux pump. Whereas spiruchostatin A and FK228-induced protracted histone acetylation, hydroxamate HDI-induced short-lived histone acetylation. Using a subset of HDI-target genes identified by microarray analysis, we demonstrated that these differences in kinetics of histone acetylation between HDI correlated with differences in the kinetics of induction or repression of specific target genes. Our results demonstrate that spiruchostatin A is a potent inhibitor of class I HDACs and anti-cancer agent. Differences in the kinetics of action of HDI may be important for the clinical application of these compounds.

  4. Rational combination treatment with histone deacetylase inhibitors and immunomodulatory drugs in multiple myeloma

    PubMed Central

    Hideshima, T; Cottini, F; Ohguchi, H; Jakubikova, J; Gorgun, G; Mimura, N; Tai, Y-T; Munshi, N C; Richardson, P G; Anderson, K C

    2015-01-01

    Immunomodulatory drugs (IMiDs) thalidomide, lenalidomide (Len) and pomalidomide trigger anti-tumor activities in multiple myeloma (MM) by targetting cereblon and thereby impacting IZF1/3, c-Myc and IRF4. Histone deacetylase inhibitors (HDACi) also downregulate c-Myc. We therefore determined whether IMiDs with HDACi trigger significant MM cell growth inhibition by inhibiting or downregulating c-Myc. Combination treatment of Len with non-selective HDACi suberoylanilide hydroxamic acid or class-I HDAC-selective inhibitor MS275 induces synergic cytotoxicity, associated with downregulation of c-Myc. Unexpectedly, we observed that decreased levels of cereblon (CRBN), a primary target protein of IMiDs, was triggered by these agents. Indeed, sequential treatment of MM cells with MS275 followed by Len shows less efficacy than simultaneous treatment with this combination. Importantly ACY1215, an HDAC6 inhibitor with minimal effects on class-I HDACs, together with Len induces synergistic MM cytotoxicity without alteration of CRBN expression. Our results showed that only modest class-I HDAC inhibition is able to induce synergistic MM cytotoxicity in combination with Len. These studies may provide the framework for utilizing HDACi in combination with Len to both avoid CRBN downregulation and enhance anti-MM activities. PMID:25978432

  5. New benzothiazole/thiazole-containing hydroxamic acids as potent histone deacetylase inhibitors and antitumor agents.

    PubMed

    Tung, Truong Thanh; Oanh, Dao Thi Kim; Dung, Phan Thi Phuong; Hue, Van Thi My; Park, Sang Ho; Han, Byung Woo; Kim, Youngsoo; Hong, Jin-Tae; Han, Sang-Bae; Nam, Nguyen-Hai

    2013-12-01

    Results from clinical studies have demonstrated that inhibitors of histone deacetylase (HDAC) enzymes possess promise for the treatment of several types of cancer. Zolinza(®) (widely known as SAHA) has been approved by the FDA for the treatment of T-cell lymphoma. As a continuity of our ongoing research to find novel small molecules to target these important enzymes, we synthesized a series of benzothiazole-containing analogues of SAHA and found several compounds with very potent anticancer cytotoxicity. In this study, three more compounds of this type, including N(1)-(6-chlorobenzo[d]thiazol-2-yl)-N(8)-hydroxyoctanediamide (3a), N(1)-[6-(trifluoromethyl)benzo[d]thiazol-2-yl]-N(8)-hydroxyoctanediamide (3b) and N(1)-(thiazol-2-yl)-N(8)-hydroxyoctanediamide (6) were synthesized and evaluated for HDAC inhibition and cytotoxic activities. All three compounds showed very potent HDAC inhibitory effects. Docking revealed that both two compounds 3a, 3b showed higher affinities towards HDAC(8) compared to SAHA. In vitro, compound 3a exhibited cytotoxicity equipotent to SAHA against five human cancer cell lines. In term of in vivo activity, compound 3a demonstrated equivalent efficacy to SAHA in mouse xenograft model.

  6. Rational combination treatment with histone deacetylase inhibitors and immunomodulatory drugs in multiple myeloma.

    PubMed

    Hideshima, T; Cottini, F; Ohguchi, H; Jakubikova, J; Gorgun, G; Mimura, N; Tai, Y-T; Munshi, N C; Richardson, P G; Anderson, K C

    2015-05-15

    Immunomodulatory drugs (IMiDs) thalidomide, lenalidomide (Len) and pomalidomide trigger anti-tumor activities in multiple myeloma (MM) by targetting cereblon and thereby impacting IZF1/3, c-Myc and IRF4. Histone deacetylase inhibitors (HDACi) also downregulate c-Myc. We therefore determined whether IMiDs with HDACi trigger significant MM cell growth inhibition by inhibiting or downregulating c-Myc. Combination treatment of Len with non-selective HDACi suberoylanilide hydroxamic acid or class-I HDAC-selective inhibitor MS275 induces synergic cytotoxicity, associated with downregulation of c-Myc. Unexpectedly, we observed that decreased levels of cereblon (CRBN), a primary target protein of IMiDs, was triggered by these agents. Indeed, sequential treatment of MM cells with MS275 followed by Len shows less efficacy than simultaneous treatment with this combination. Importantly ACY1215, an HDAC6 inhibitor with minimal effects on class-I HDACs, together with Len induces synergistic MM cytotoxicity without alteration of CRBN expression. Our results showed that only modest class-I HDAC inhibition is able to induce synergistic MM cytotoxicity in combination with Len. These studies may provide the framework for utilizing HDACi in combination with Len to both avoid CRBN downregulation and enhance anti-MM activities.

  7. Histone deacetylase 3 inhibits new tumor suppressor gene DTWD1 in gastric cancer

    PubMed Central

    Ma, Yanning; Yue, Yongfang; Pan, Min; Sun, Jie; Chu, Jue; Lin, Xiaoying; Xu, Wenxia; Feng, Lifeng; Chen, Yan; Chen, Dingwei; Shin, Vivian Y; Wang, Xian; Jin, Hongchuan

    2015-01-01

    Cancer epigenetics plays an important role in the pathogenesis of many cancers including gastric cancer. Histone deacetylases (HDACs) emerge as exciting therapeutic targets for cancer treatment and prevention. In this study, we identified DTWD1 as one of the 122 genes upregulated after treatment of trichostatin A (TSA) in two gastric cancer cell lines. Moreover, DTWD1 was downregulated in gastric cancer cell lines and primary gastric carcinoma tissues. It was further identified as the new target of p53. Then we revealed that HDAC3 downregulated DTWD1 by disrupting the interaction of p53 with DTWD1 promoter. Furthermore, DTWD1 functioned as a tumor suppressor by downregulating cyclin B1 expression to inhibit proliferation. In summary, as the new p53 target gene, DTWD1 was downregulated in gastric cancer by HDAC3 and acted as a novel tumor suppressor gene. Specific inhibitors of HDAC3 might be a new approach for gastric cancer treatment by activating DTWD1 expression. PMID:25973305

  8. Selective transcription and cellular proliferation induced by PDGF require histone deacetylase activity

    SciTech Connect

    Catania, Annunziata; Iavarone, Carlo; Carlomagno, Stella M.; Chiariello, Mario . E-mail: chiariel@unina.it

    2006-05-05

    Histone deacetylases (HDACs) are key regulatory enzymes involved in the control of gene expression and their inhibition by specific drugs has been widely correlated to cell cycle arrest, terminal differentiation, and apoptosis. Here, we investigated whether HDAC activity was required for PDGF-dependent signal transduction and cellular proliferation. Exposure of PDGF-stimulated NIH3T3 fibroblasts to the HDAC inhibitor trichostatin A (TSA) potently repressed the expression of a group of genes correlated to PDGF-dependent cellular growth and pro-survival activity. Moreover, we show that TSA interfered with STAT3-dependent transcriptional activity induced by PDGF. Still, neither phosphorylation nor nuclear translocation and DNA-binding in vitro and in vivo of STAT3 were affected by using TSA to interfere with PDGF stimulation. Finally, TSA treatment resulted in the suppression of PDGF-dependent cellular proliferation without affecting cellular survival of NIH3T3 cells. Our data indicate that inhibition of HDAC activity antagonizes the mitogenic effect of PDGF, suggesting that these drugs may specifically act on the expression of STAT-dependent, PDGF-responsive genes.

  9. Histone deacetylases control module-specific phenotypic plasticity in beetle weapons

    PubMed Central

    Ozawa, Takane; Mizuhara, Tomoko; Arata, Masataka; Shimada, Masakazu; Niimi, Teruyuki; Okada, Kensuke; Okada, Yasukazu; Ohta, Kunihiro

    2016-01-01

    Nutritional conditions during early development influence the plastic expression of adult phenotypes. Among several body modules of animals, the development of sexually selected exaggerated traits exhibits striking nutrition sensitivity, resulting in positive allometry and hypervariability distinct from other traits. Using de novo RNA sequencing and comprehensive RNA interference (RNAi) for epigenetic modifying factors, we found that histone deacetylases (HDACs) and polycomb group (PcG) proteins preferentially influence the size of mandibles (exaggerated male weapon) and demonstrate nutrition-dependent hypervariability in the broad-horned flour beetle, Gnatocerus cornutus. RNAi-mediated HDAC1 knockdown (KD) in G. cornutus larvae caused specific curtailment of mandibles in adults, whereas HDAC3 KD led to hypertrophy. Notably, these KDs conferred opposite effects on wing size, but little effect on the size of the core body and genital modules. PcG RNAi also reduced adult mandible size. These results suggest that the plastic development of exaggerated traits is controlled in a module-specific manner by HDACs. PMID:27956627

  10. Suberoylanilide Hydroxamic Acid (SAHA)-Induced Dynamics of a Human Histone Deacetylase Protein Interaction Network*

    PubMed Central

    Sardiu, Mihaela E.; Smith, Karen T.; Groppe, Brad D.; Gilmore, Joshua M.; Saraf, Anita; Egidy, Rhonda; Peak, Allison; Seidel, Chris W.; Florens, Laurence; Workman, Jerry L.; Washburn, Michael P.

    2014-01-01

    Histone deacetylases (HDACs) are targets for cancer therapy. Suberoylanilide hydroxamic acid (SAHA) is an HDAC inhibitor approved by the U.S. Food and Drug Administration for the treatment of cutaneous T-cell lymphoma. To obtain a better mechanistic understanding of the Sin3/HDAC complex in cancer, we extended its protein–protein interaction network and identified a mutually exclusive pair within the complex. We then assessed the effects of SAHA on the disruption of the complex network through six homologous baits. SAHA perturbs multiple protein interactions and therefore compromises the composition of large parts of the Sin3/HDAC network. A comparison of the effect of SAHA treatment on gene expression in breast cancer cells to a knockdown of the ING2 subunit indicated that a portion of the anticancer effects of SAHA may be attributed to the disruption of ING2's association with the complex. Our dynamic protein interaction network resource provides novel insights into the molecular mechanism of SAHA action and demonstrates the potential for drugs to rewire networks. PMID:25073741

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

    PubMed Central

    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

    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

  12. Histone Deacetylases and Mood Disorders: Epigenetic Programming in Gene-Environment Interactions

    PubMed Central

    Machado-Vieira, Rodrigo; Ibrahim, Lobna; Zarate, Carlos A.

    2010-01-01

    Epigenetics involves molecular mechanisms related to gene expression independent of DNA sequence, mostly mediated by modification of chromatin histones. It has recently been suggested that these transcriptional changes may be implicated in the pathophysiology of mood disorders. In addition, histone deacetylase (HDAC) inhibitors have been shown to control epigenetic programming associated with the regulation of cognition and behavior, and may reverse dysfunctional epigenetic regulation associated with early life events in preclinical models. In this context, the active and continuous adaptation of chromatin, and the access of gene promoters to transcription factor mechanisms may represent a potential therapeutic target in the treatment of mood disorders such as bipolar disorder (BD) and major depressive disorder (MDD). Notably, the standard mood stabilizer valproate (VPA) has been shown to modulate the epigenome by inhibiting HDACs. However, several potential limitations are associated with this class of agents, including lack of selectivity for specific HDAC isoforms as well as risk of potentially serious side effects. Further studies regarding the potential role of chromatin remodeling in the mechanism of action of antidepressants and mood stabilizers are necessary to clarify the potential role of this class of agents as therapeutics for mood disorders. PMID:20961400

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

    PubMed Central

    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

    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

  14. Inhibition of histone deacetylases facilitates extinction and attenuates reinstatement of nicotine self-administration in rats.

    PubMed

    Castino, Matthew R; Cornish, Jennifer L; Clemens, Kelly J

    2015-01-01

    Chromatin remodelling is integral to the formation of long-term memories. Recent evidence suggests that histone modification may play a role in the persistence of memories associated with drug use. The present series of experiments aimed to examine the effect of histone deacetylase (HDAC) inhibition on the extinction and reinstatement of nicotine self-administration. Rats were trained to intravenously self-administer nicotine for 12 days on a fixed-ratio 1 schedule. In Experiment 1, responding was then extinguished through removal of nicotine and response-contingent cues. After each extinction session, the HDAC inhibitor, sodium butyrate (NaB), was administered immediately, or six hours after each session. In Experiment 2, response-contingent cues remained available across extinction to increase rates of responding during this phase, and NaB was administered immediately after the session. Finally, in Experiment 3, the effect of NaB treatment on extinction of responding for sucrose pellets was assessed. Across all experiments reinstatement to the cue and/or the reward itself was then tested. In the first experiment, treatment with NaB significantly attenuated nicotine and nicotine + cue reinstatement when administered immediately, but not six hours after each extinction session. When administered after cue-extinction (Expt. 2), NaB treatment specifically facilitated the rate of extinction across sessions, indicating that HDAC inhibition enhanced consolidation of the extinction memory. In contrast, there was no effect of NaB on the extinction and reinstatement of sucrose-seeking (Expt. 3), indicating that the observed effects are specific to a drug context. These results provide the first demonstration that HDAC inhibition facilitates the extinction of responding for an intravenously self-administered drug of abuse and further highlight the potential of HDAC inhibitors in the treatment of drug addiction.

  15. General Base-General Acid Catalysis in Human Histone Deacetylase 8.

    PubMed

    Gantt, Sister M Lucy; Decroos, Christophe; Lee, Matthew S; Gullett, Laura E; Bowman, Christine M; Christianson, David W; Fierke, Carol A

    2016-02-09

    Histone deacetylases (HDACs) regulate cellular processes such as differentiation and apoptosis and are targeted by anticancer therapeutics in development and in the clinic. HDAC8 is a metal-dependent class I HDAC and is proposed to use a general acid-base catalytic pair in the mechanism of amide bond hydrolysis. Here, we report site-directed mutagenesis and enzymological measurements to elucidate the catalytic mechanism of HDAC8. Specifically, we focus on the catalytic function of Y306 and the histidine-aspartate dyads H142-D176 and H143-D183. Additionally, we report X-ray crystal structures of four representative HDAC8 mutants: D176N, D176N/Y306F, D176A/Y306F, and H142A/Y306F. These structures provide a useful framework for understanding enzymological measurements. The pH dependence of kcat/KM for wild-type Co(II)-HDAC8 is bell-shaped with two pKa values of 7.4 and 10.0. The upper pKa reflects the ionization of the metal-bound water molecule and shifts to 9.1 in Zn(II)-HDAC8. The H142A mutant has activity 230-fold lower than that of wild-type HDAC8, but the pKa1 value is not altered. Y306F HDAC8 is 150-fold less active than the wild-type enzyme; crystal structures show that Y306 hydrogen bonds with the zinc-bound substrate carbonyl, poised for transition state stabilization. The H143A and H142A/H143A mutants exhibit activity that is >80000-fold lower than that of wild-type HDAC8; the buried D176N and D176A mutants have significant catalytic effects, with more subtle effects caused by D183N and D183A. These enzymological and structural studies strongly suggest that H143 functions as a single general base-general acid catalyst, while H142 remains positively charged and serves as an electrostatic catalyst for transition state stabilization.

  16. Contrasting Effects of Histone Deacetylase Inhibitors on Reward and Aversive Olfactory Memories in the Honey Bee.

    PubMed

    Lockett, Gabrielle A; Wilkes, Fiona; Helliwell, Paul; Maleszka, Ryszard

    2014-06-10

    Much of what we have learnt from rodent models about the essential role of epigenetic processes in brain plasticity has made use of aversive learning, yet the role of histone acetylation in aversive memory in the honey bee, a popular invertebrate model for both memory and epigenetics, was previously unknown. We examined the effects of histone deacetylase (HDAC) inhibition on both aversive and reward olfactory associative learning in a discrimination proboscis extension reflex (PER) assay. We report that treatment with the HDAC inhibitors APHA compound 8 (C8), phenylbutyrate (PB) or sodium butyrate (NaB) impaired discrimination memory due to impairment of aversive memory in a dose-dependent manner, while simultaneously having no effect on reward memory. Treatment with C8 1 h before training, 1 h after training or 1 h before testing, impaired aversive but not reward memory at test. C8 treatment 1 h before training also improved aversive but not reward learning during training. PB treatment only impaired aversive memory at test when administered 1 h after training, suggesting an effect on memory consolidation specifically. Specific impairment of aversive memory (but not reward memory) by HDAC inhibiting compounds was robust, reproducible, occurred following treatment with three drugs targeting the same mechanism, and is likely to be genuinely due to alterations to memory as sucrose sensitivity and locomotion were unaffected by HDAC inhibitor treatment. This pharmacological dissection of memory highlights the involvement of histone acetylation in aversive memory in the honey bee, and expands our knowledge of epigenetic control of neural plasticity in invertebrates.

  17. Histone Deacetylase Inhibitor Trichostatin A Ameliorated Endotoxin-Induced Neuroinflammation and Cognitive Dysfunction

    PubMed Central

    Hsing, Chung-Hsi; Hung, Shih-Kai; Chen, Yeong-Chang; Wei, Tsui-Shan; Sun, Ding-Ping; Wang, Jhi-Joung; Yeh, Ching-Hua

    2015-01-01

    Excessive production of cytokines by microglia may cause cognitive dysfunction and long-lasting behavioral changes. Activating the peripheral innate immune system stimulates cytokine secretion in the central nervous system, which modulates cognitive function. Histone deacetylases (HDACs) modulate cytokine synthesis and release. Trichostatin A (TSA), an HDAC inhibitor, is documented to be anti-inflammatory and neuroprotective. We investigated whether TSA reduces lipopolysaccharide- (LPS-) induced neuroinflammation and cognitive dysfunction. ICR mice were first intraperitoneally (i.p.) injected with vehicle or TSA (0.3 mg/kg). One hour later, they were injected (i.p.) with saline or Escherichia coli LPS (1 mg/kg). We analyzed the food and water intake, body weight loss, and sucrose preference of the injected mice and then determined the microglia activation and inflammatory cytokine expression in the brains of LPS-treated mice and LPS-treated BV-2 microglial cells. In the TSA-pretreated mice, microglial activation was lower, anhedonia did not occur, and LPS-induced cognitive dysfunction (anorexia, weight loss, and social withdrawal) was attenuated. Moreover, mRNA expression of HDAC2, HDAC5, indoleamine 2,3-dioxygenase (IDO), TNF-α, MCP-1, and IL-1β in the brain of LPS-challenged mice and in the LPS-treated BV-2 microglial cells was lower. TSA diminished LPS-induced inflammatory responses in the mouse brain and modulated the cytokine-associated changes in cognitive function, which might be specifically related to reducing HDAC2 and HDAC5 expression. PMID:26273133

  18. Histone Deacetylase Inhibitors Promote Mitochondrial Reactive Oxygen Species Production and Bacterial Clearance by Human Macrophages.

    PubMed

    Ariffin, Juliana K; das Gupta, Kaustav; Kapetanovic, Ronan; Iyer, Abishek; Reid, Robert C; Fairlie, David P; Sweet, Matthew J

    2015-12-28

    Broad-spectrum histone deacetylase inhibitors (HDACi) are used clinically as anticancer agents, and more isoform-selective HDACi have been sought to modulate other conditions, including chronic inflammatory diseases. Mouse studies suggest that HDACi downregulate immune responses and may compromise host defense. However, their effects on human macrophage antimicrobial responses are largely unknown. Here, we show that overnight pretreatment of human macrophages with HDACi prior to challenge with Salmonella enterica serovar Typhimurium or Escherichia coli results in significantly reduced intramacrophage bacterial loads, which likely reflect the fact that this treatment regime impairs phagocytosis. In contrast, cotreatment of human macrophages with HDACi at the time of bacterial challenge did not impair phagocytosis; instead, HDACi cotreatment actually promoted clearance of intracellular S. Typhimurium and E. coli. Mechanistically, treatment of human macrophages with HDACi at the time of bacterial infection enhanced mitochondrial reactive oxygen species generation by these cells. The capacity of HDACi to promote the clearance of intracellular bacteria from human macrophages was abrogated when cells were pretreated with MitoTracker Red CMXRos, which perturbs mitochondrial function. The HDAC6-selective inhibitor tubastatin A promoted bacterial clearance from human macrophages, whereas the class I HDAC inhibitor MS-275, which inhibits HDAC1 to -3, had no effect on intracellular bacterial loads. These data are consistent with HDAC6 and/or related HDACs constraining mitochondrial reactive oxygen species production from human macrophages during bacterial challenge. Our findings suggest that, whereas long-term HDACi treatment regimes may potentially compromise host defense, selective HDAC inhibitors may have applications in treating acute bacterial infections.

  19. Histone Deacetylase Inhibitors Promote Mitochondrial Reactive Oxygen Species Production and Bacterial Clearance by Human Macrophages

    PubMed Central

    Ariffin, Juliana K.; das Gupta, Kaustav; Kapetanovic, Ronan; Iyer, Abishek; Reid, Robert C.; Fairlie, David P.

    2015-01-01

    Broad-spectrum histone deacetylase inhibitors (HDACi) are used clinically as anticancer agents, and more isoform-selective HDACi have been sought to modulate other conditions, including chronic inflammatory diseases. Mouse studies suggest that HDACi downregulate immune responses and may compromise host defense. However, their effects on human macrophage antimicrobial responses are largely unknown. Here, we show that overnight pretreatment of human macrophages with HDACi prior to challenge with Salmonella enterica serovar Typhimurium or Escherichia coli results in significantly reduced intramacrophage bacterial loads, which likely reflect the fact that this treatment regime impairs phagocytosis. In contrast, cotreatment of human macrophages with HDACi at the time of bacterial challenge did not impair phagocytosis; instead, HDACi cotreatment actually promoted clearance of intracellular S. Typhimurium and E. coli. Mechanistically, treatment of human macrophages with HDACi at the time of bacterial infection enhanced mitochondrial reactive oxygen species generation by these cells. The capacity of HDACi to promote the clearance of intracellular bacteria from human macrophages was abrogated when cells were pretreated with MitoTracker Red CMXRos, which perturbs mitochondrial function. The HDAC6-selective inhibitor tubastatin A promoted bacterial clearance from human macrophages, whereas the class I HDAC inhibitor MS-275, which inhibits HDAC1 to -3, had no effect on intracellular bacterial loads. These data are consistent with HDAC6 and/or related HDACs constraining mitochondrial reactive oxygen species production from human macrophages during bacterial challenge. Our findings suggest that, whereas long-term HDACi treatment regimes may potentially compromise host defense, selective HDAC inhibitors may have applications in treating acute bacterial infections. PMID:26711769

  20. Functional interplay between cylindromatosis and histone deacetylase 6 in ciliary homeostasis revealed by phenotypic analysis of double knockout mice

    PubMed Central

    Ran, Jie; Yu, Fan; Qin, Juan; Zhang, Yijun; Yang, Yunfan; Li, Dengwen; Zhou, Jun; Liu, Min

    2016-01-01

    Cilia are present in most vertebrate tissues with a wide variety of functions, and abnormalities of cilia are linked to numerous human disorders. However, the molecular events underlying ciliary homeostasis are poorly understood. In this study, we generated double knockout (DKO) mice for the deubiquitinase cylindromatosis (CYLD) and histone deacetylase 6 (HDAC6), two critical ciliary regulators. The Cyld/Hdac6 DKO mice were phenotypically normal and showed no obvious variances in weight or behavior compared with their wild-type littermates. Strikingly, Cyld loss-induced ciliary defects in the testis, trachea, and kidney were abrogated in the Cyld/Hdac6 DKO mice. In addition, the diminished α-tubulin acetylation and impaired sonic hedgehog signaling caused by loss of Cyld were largely restored by simultaneous deletion of Hdac6. We further found by immunofluorescence microscopy a colocalization of CYLD and HDAC6 at the centrosome/basal body and, interestingly, loss of Cyld promoted the localization of HDAC6 at the centrosome/basal body. These findings provide physiological insight into the ciliary role of the CYLD/HDAC6 axis and suggest a functional interplay between these two proteins in ciliary homeostasis. PMID:27028867

  1. The Hos2 Histone Deacetylase Controls Ustilago maydis Virulence through Direct Regulation of Mating-Type Genes

    PubMed Central

    Elías-Villalobos, Alberto; Fernández-Álvarez, Alfonso; Moreno-Sánchez, Ismael; Helmlinger, Dominique; Ibeas, José I.

    2015-01-01

    Morphological changes are critical for host colonisation in plant pathogenic fungi. These changes occur at specific stages of their pathogenic cycle in response to environmental signals and are mediated by transcription factors, which act as master regulators. Histone deacetylases (HDACs) play crucial roles in regulating gene expression, for example by locally modulating the accessibility of chromatin to transcriptional regulators. It has been reported that HDACs play important roles in the virulence of plant fungi. However, the specific environment-sensing pathways that control fungal virulence via HDACs remain poorly characterised. Here we address this question using the maize pathogen Ustilago maydis. We find that the HDAC Hos2 is required for the dimorphic switch and pathogenic development in U. maydis. The deletion of hos2 abolishes the cAMP-dependent expression of mating type genes. Moreover, ChIP experiments detect Hos2 binding to the gene bodies of mating-type genes, which increases in proportion to their expression level following cAMP addition. These observations suggest that Hos2 acts as a downstream component of the cAMP-PKA pathway to control the expression of mating-type genes. Interestingly, we found that Clr3, another HDAC present in U. maydis, also contributes to the cAMP-dependent regulation of mating-type gene expression, demonstrating that Hos2 is not the only HDAC involved in this control system. Overall, our results provide new insights into the role of HDACs in fungal phytopathogenesis. PMID:26317403

  2. Identification of Components of the Murine Histone Deacetylase 6 Complex: Link between Acetylation and Ubiquitination Signaling Pathways

    PubMed Central

    Seigneurin-Berny, Daphné; Verdel, André; Curtet, Sandrine; Lemercier, Claudie; Garin, Jérôme; Rousseaux, Sophie; Khochbin, Saadi

    2001-01-01

    The immunopurification of the endogenous cytoplasmic murine histone deacetylase 6 (mHDAC6), a member of the class II HDACs, from mouse testis cytosolic extracts allowed the identification of two associated proteins. Both were mammalian homologues of yeast proteins known to interact with each other and involved in the ubiquitin signaling pathway: p97/VCP/Cdc48p, a homologue of yeast Cdc48p, and phospholipase A2-activating protein, a homologue of yeast UFD3 (ubiquitin fusion degradation protein 3). Moreover, in the C-terminal region of mHDAC6, a conserved zinc finger-containing domain named ZnF-UBP, also present in several ubiquitin-specific proteases, was discovered and was shown to mediate the specific binding of ubiquitin by mHDAC6. By using a ubiquitin pull-down approach, nine major ubiquitin-binding proteins were identified in mouse testis cytosolic extracts, and mHDAC6 was found to be one of them. All of these findings strongly suggest that mHDAC6 could be involved in the control of protein ubiquitination. The investigation of biochemical properties of the mHDAC6 complex in vitro further supported this hypothesis and clearly established a link between protein acetylation and protein ubiquitination. PMID:11689694

  3. Imaging Epigenetic Regulation by Histone Deacetylases in the Brain using PET/MRI with 18F-FAHA

    PubMed Central

    Yeh, Hsien-Hsien; Tian, Mei; Hinz, Rainer; Young, Daniel; Shavrin, Alexander; Mukhapadhyay, Uday; Flores, Leo G.; Balatoni, Julius; Soghomonyan, Suren; Jeong, Hwan J.; Pal, Ashutosh; Uthamanthil, Rajesh; Jackson, James N.; Nishii, Ryuichi; Mizuma, Hiroshi; Onoe, Hirotaka; Kagawa, Shinya; Higashi, Tatsuya; Fukumitsu, Nobuyoshi; Alauddin, Mian; Tong, William; Herholz, Karl; Gelovani, Juri G.

    2012-01-01

    Epigenetic modifications mediated by histone deacetylases (HDACs) play important roles in the mechanisms of different neurologic diseases and HDAC inhibitors (HDACIs) have shown promise in therapy. However, pharmacodynamic profiles of many HDACIs in the brain remain largely unknown due to the lack of validated methods for noninvasive imaging of HDACs expression-activity. In this study, dynamic PET/CT imaging was performed in 4 rhesus macaques using [18F]FAHA, a novel HDAC substrate, and [18F]fluoroacetate, the major radio-metabolite of [18F]FAHA, and fused with corresponding MR images of the brain. Quantification of [18F]FAHA accumulation in the brain was performed using a customized dual-tracer pharmacokinetic model. Immunohistochemical analyses of brain tissue revealed the heterogeneity of expression of individual HDACs in different brain structures and cell types and confirmed that PET/CT/MRI with [18F]FAHA reflects the level of expression-activity of HDAC class IIa enzymes. Furthermore, PET/CT/MRI with [18F]FAHA enabled non-invasive, quantitative assessment of pharmacodynamics of HDACs inhibitor SAHA in the brain. PMID:22995777

  4. Histone Deacetylase Inhibitors Trichostatin A and MCP30 Relieve Benzene-Induced Hematotoxicity via Restoring Topoisomerase IIα.

    PubMed

    Chen, Jingjing; Zheng, Zhouyi; Chen, Yi; Li, Jiaqi; Qian, Shanhu; Shi, Yifen; Sun, Lan; Han, Yixiang; Zhang, Shenghui; Yu, Kang

    2016-01-01

    Dysfunction of histone acetylation inhibits topoisomerase IIα (Topo IIα), which is implicated in benzene-induced hematotoxicity in patients with chronic benzene exposure. Whether histone deacetylase (HDAC) inhibitors can relieve benzene-induced hematotoxicity remains unclear. Here we showed that hydroquinone, a main metabolite of benzene, increased the HDAC activity, decreased the Topo IIα expression and induced apoptosis in human bone marrow mononuclear cells in vitro, and treatment with two HDAC inhibitors, namely trichostatin A (TSA) or a mixture of ribosome-inactivating proteins MCP30, almost completely reversed these effects. We further established a benzene poisoning murine model by inhaling benzene vapor in a container and found that benzene poisoning decreased the expression and activity of Topo IIα, and impaired acetylation of histone H4 and H3. The analysis of regulatory factors of Topo IIα promoter found that benzene poisoning decreased the mRNA levels of SP1 and C-MYB, and increased the mRNA level of SP3. Both TSA and MCP30 significantly enhanced the acetylation of histone H3 and H4 in Topo IIα promoter and increased the expression and activity of Topo IIα in benzene poisoning mice, which contributed to relieve the symptoms of hematotoxicity. Thus, treatment with HDAC inhibitors represents an attractive approach to reduce benzene-induced hematotoxicity.

  5. Epigenetic targeting of histone deacetylase: therapeutic potential in Parkinson's disease?

    PubMed

    Harrison, Ian F; Dexter, David T

    2013-10-01

    Parkinson's disease (PD) is the most common movement disorder affecting more than 4million people worldwide. The primary motor symptoms of the disease are due to degeneration of dopaminergic nigrostriatal neurons. Dopamine replacement therapies have therefore revolutionised disease management by partially controlling these symptoms. However these drugs can produce debilitating side effects when used long term and do not protect degenerating neurons against death. Recent evidence has highlighted a pathological imbalance in PD between the acetylation and deacetylation of the histone proteins around which deoxyribonucleic acid (DNA) is coiled, in favour of excessive histone deacetylation. This mechanism of adding/removing acetyl groups to histone lysine residues is one of many epigenetic regulatory processes which control the expression of genes, many of which will be essential for neuronal survival. Hence, such epigenetic modifications may have a pathogenic role in PD. It has therefore been hypothesised that if this pathological imbalance can be corrected with the use of histone deacetylase inhibiting agents then neurodegeneration observed in PD can be ameliorated. This article will review the current literature with regard to epigenetic changes in PD and the use of histone deacetylase inhibitors (HDACIs) in PD: examining the evidence of the neuroprotective effects of numerous HDACIs in cellular and animal models of Parkinsonian cell death. Ultimately answering the question: does epigenetic targeting of histone deacetylases hold therapeutic potential in PD?

  6. Global histone deacetylase enzymatic activity is an independent prognostic marker associated with a shorter overall survival in chronic lymphocytic leukemia patients.

    PubMed

    Van Damme, Michaël; Crompot, Emerence; Meuleman, Nathalie; Mineur, Philippe; Dessars, Barbara; El Housni, Hakim; Bron, Dominique; Lagneaux, Laurence; Stamatopoulos, Basile

    2014-10-01

    Histone deacetylases (HDAC) play a crucial role in transcriptional regulation and are often deregulated in many cancers. However, global HDAC enzymatic activity has never been investigated in Chronic Lymphocytic Leukemia (CLL). We measured HDAC activity in protein extracts from CD19+ B-cells purified from 114 CLL patients with a median follow-up of 91 months (range: 11-376). HDAC activity was equivalent in CLL and normal B-cells but higher in patients who died during the study than in living patients (152.1 vs. 65.04 pmol; P = 0.0060). Furthermore, HDAC activity correlated with treatment-free survival (TFS; P = 0.0156) and overall survival (OS; P < 0.0001): patients with low HDAC activity (n = 75) had a median TFS and OS of 101 and > 376 months, respectively, whereas patients with high HDAC activity (n = 39) had a median TFS and OS of 47 and 137 months, respectively. Multivariate analyses indicated that HDAC activity is an independent predictor of OS (hazard ratio = 7.68; P = 0.0017). Finally, HDAC activity increased after B-cell receptor stimulation using IgM, suggesting a role for microenvironment stimuli (n = 10; P = 0.0371). In conclusion, high HDAC activity in CLL B-cells is associated with shorter TFS and OS and is an independent marker of OS, refining the use of other prognostic factors. This work provides a biological base for the use of HDAC inhibitors in CLL treatment.

  7. LSD1 regulates pluripotency of embryonic stem/carcinoma cells through histone deacetylase 1-mediated deacetylation of histone H4 at lysine 16.

    PubMed

    Yin, Feng; Lan, Rongfeng; Zhang, Xiaoming; Zhu, Linyu; Chen, Fangfang; Xu, Zhengshuang; Liu, Yuqing; Ye, Tao; Sun, Hong; Lu, Fei; Zhang, Hui

    2014-01-01

    LSD1 is essential for the maintenance of pluripotency of embryonic stem (ES) or embryonic carcinoma/teratocarcinoma (EC) cells. We have previously developed novel LSD1 inhibitors that selectively inhibit ES/EC cells. However, the critical targets of LSD1 remain unclear. Here, we found that LSD1 interacts with histone deacetylase 1 (HDAC1) to regulate the proliferation of ES/EC cells through acetylation of histone H4 at lysine 16 (H4K16), which we show is a critical substrate of HDAC1. The LSD1 demethylase and HDAC1 deacetylase activities were both inactivated if one of them in the complex was chemically inhibited in ES/EC cells or in reconstituted protein complexes. Loss of HDAC1 phenocopied the selective growth-inhibitory effects and increased the levels of H3K4 methylation and H4K16 acetylation of LSD1 inactivation on ES/EC cells. Reduction of acetylated H4K16 by ablation of the acetyltransferase males absent on the first (MOF) is sufficient to rescue the growth inhibition induced by LSD1 inactivation. While LSD1 or HDAC1 inactivation caused the downregulation of Sox2 and Oct4 and induction of differentiation genes, such as FOXA2 or BMP2, depletion of MOF restored the levels of Sox2, Oct4, and FoxA2 in LSD1-deficient cells. Our studies reveal a novel mechanism by which LSD1 acts through the HDAC1- and MOF-mediated regulation of H4K16 acetylation to maintain the pluripotency of ES/EC cells.

  8. Cytoplasmic Localization of RUNX3 via Histone Deacetylase-Mediated SRC Expression in Oxidative-Stressed Colon Cancer Cells.

    PubMed

    Kang, Kyoung Ah; Piao, Mei Jing; Ryu, Yea Seong; Maeng, Young Hee; Hyun, Jin Won

    2016-12-19

    Runt domain transcription factor 3 (RUNX3) is a transcription factor that functions as a tumor suppressor. RUNX3 is frequently inactivated by epigenetic silencing or its protein mislocalization (cytoplasmic localization) in many cancer types. This study investigated whether oxidative stress induces redistribution of RUNX3 from the nucleus to the cytoplasm. The cytoplasmic localization of RUNX3 was associated with oxidative stress-induced RUNX3 phosphorylation at tyrosine residues via SRC activation. Moreover, oxidative stress increased expression of histone deacetylases (HDACs). RUNX3 phosphorylation and SRC expression induced by oxidative stress were inhibited by knockdown of HDAC1, restoring the nuclear localization of RUNX3 under oxidative stress. In conclusion, these results demonstrate that HDAC1- and SRC-mediated phosphorylation of RUNX3 induced by oxidative stress is associated with the cytoplasmic localization of RUNX3 and can lead to RUNX3 inactivation and carcinogenesis. J. Cell. Physiol. 9999: 1-8, 2016. © 2016 Wiley Periodicals, Inc.

  9. Histone Deacetylase Inhibitors (HDACi) Cause the Selective Depletion of Bromodomain Containing Proteins (BCPs).

    PubMed

    Mackmull, Marie-Therese; Iskar, Murat; Parca, Luca; Singer, Stephan; Bork, Peer; Ori, Alessandro; Beck, Martin

    2015-05-01

    Histone deacetylases (HDACs) and acetyltransferases control the epigenetic regulation of gene expression through modification of histone marks. Histone deacetylase inhibitors (HDACi) are small molecules that interfere with histone tail modification, thus altering chromatin structure and epigenetically controlled pathways. They promote apoptosis in proliferating cells and are promising anticancer drugs. While some HDACi have already been approved for therapy and others are in different phases of clinical trials, the exact mechanism of action of this drug class remains elusive. Previous studies have shown that HDACis cause massive changes in chromatin structure but only moderate changes in gene expression. To what extent these changes manifest at the protein level has never been investigated on a proteome-wide scale. Here, we have studied HDACi-treated cells by large-scale mass spectrometry based proteomics. We show that HDACi treatment affects primarily the nuclear proteome and induces a selective decrease of bromodomain-containing proteins (BCPs), the main readers of acetylated histone marks. By combining time-resolved proteome and transcriptome profiling, we show that BCPs are affected at the protein level as early as 12 h after HDACi treatment and that their abundance is regulated by a combination of transcriptional and post-transcriptional mechanisms. Using gene silencing, we demonstrate that the decreased abundance of BCPs is sufficient to mediate important transcriptional changes induced by HDACi. Our data reveal a new aspect of the mechanism of action of HDACi that is mediated by an interplay between histone acetylation and the abundance of BCPs. Data are available via ProteomeXchange with identifier PXD001660 and NCBI Gene Expression Omnibus with identifier GSE64689.

  10. Bicyclic-Capped Histone Deacetylase 6 Inhibitors with Improved Activity in a Model of Axonal Charcot-Marie-Tooth Disease.

    PubMed

    Shen, Sida; Benoy, Veronick; Bergman, Joel A; Kalin, Jay H; Frojuello, Mariana; Vistoli, Giulio; Haeck, Wanda; Van Den Bosch, Ludo; Kozikowski, Alan P

    2016-02-17

    Charcot-Marie-Tooth (CMT) disease is a disorder of the peripheral nervous system where progressive degeneration of motor and sensory nerves leads to motor problems and sensory loss and for which no pharmacological treatment is available. Recently, it has been shown in a model for the axonal form of CMT that histone deacetylase 6 (HDAC6) can serve as a target for the development of a pharmacological therapy. Therefore, we aimed at developing new selective and activity-specific HDAC6 inhibitors with improved biochemical properties. By utilizing a bicyclic cap as the structural scaffold from which to build upon, we developed several analogues that showed improved potency compared to tubastatin A while maintaining excellent selectivity compared to HDAC1. Further screening in N2a cells examining both the acetylation of α-tubulin and histones narrowed down the library of compounds to three potent and selective HDAC6 inhibitors. In mutant HSPB1-expressing DRG neurons, serving as an in vitro model for CMT2, these inhibitors were able to restore the mitochondrial axonal transport deficits. Combining structure-based development of HDAC6 inhibitors, screening in N2a cells and in a neuronal model for CMT2F, and preliminary ADMET and pharmacokinetic profiles, resulted in the selection of compound 23d that possesses improved biochemical, functional, and druglike properties compared to tubastatin A.

  11. Structure of Prokaryotic Polyamine Deacetylase Reveals Evolutionary Functional Relationships with Eukaryotic Histone Deacetylases

    PubMed Central

    Lombardi, Patrick M.; Angell, Heather D.; Whittington, Douglas A.; Flynn, Erin F.; Rajashankar, Kanagalaghatta R.; Christianson, David W.

    2011-01-01

    Polyamines are a ubiquitous class of polycationic small molecules that can influence gene expression by binding to nucleic acids. Reversible polyamine acetylation regulates nucleic acid binding and is required for normal cell cycle progression and proliferation. Here, we report the structures of Mycoplana ramosa acetylpolyamine amidohydrolase (APAH) complexed with a transition state analogue and a hydroxamate inhibitor, and an inactive mutant complexed with two acetylpolyamine substrates. The structure of APAH is the first of a histone deacetylase-like oligomer and reveals that an 18-residue insert in the L2 loop promotes dimerization and the formation of an 18-Å long “L”-shaped active site tunnel at the dimer interface, accessible only to narrow and flexible substrates. The importance of dimerization for polyamine deacetylase function leads to the suggestion that a comparable dimeric or double-domain histone deacetylase could catalyze polyamine deacetylation reactions in eukaryotes. PMID:21268586

  12. Structure of Prokaryotic Polyamine Deacetylase Reveals Evolutionary Functional Relationships with Eukaryotic Histone Deacetylases

    SciTech Connect

    P Lombardi; H Angell; D Whittington; E Flynn; K Rajashankar; D Christianson

    2011-12-31

    Polyamines are a ubiquitous class of polycationic small molecules that can influence gene expression by binding to nucleic acids. Reversible polyamine acetylation regulates nucleic acid binding and is required for normal cell cycle progression and proliferation. Here, we report the structures of Mycoplana ramosa acetylpolyamine amidohydrolase (APAH) complexed with a transition state analogue and a hydroxamate inhibitor and an inactive mutant complexed with two acetylpolyamine substrates. The structure of APAH is the first of a histone deacetylase-like oligomer and reveals that an 18-residue insert in the L2 loop promotes dimerization and the formation of an 18 {angstrom} long 'L'-shaped active site tunnel at the dimer interface, accessible only to narrow and flexible substrates. The importance of dimerization for polyamine deacetylase function leads to the suggestion that a comparable dimeric or double-domain histone deacetylase could catalyze polyamine deacetylation reactions in eukaryotes.

  13. Inhibition of histone deacetylases by chlamydocin induces apoptosis and proteasome-mediated degradation of survivin.

    PubMed

    De Schepper, Stefanie; Bruwiere, Hélène; Verhulst, Tinne; Steller, Ulf; Andries, Luc; Wouters, Walter; Janicot, Michel; Arts, Janine; Van Heusden, Jim

    2003-02-01

    The naturally occurring cyclic tetrapeptide chlamydocin is a very potent inhibitor of cell proliferation. Here we show that chlamydocin is a highly potent histone deacetylase (HDAC) inhibitor, inhibiting HDAC activity in vitro with an IC(50) of 1.3 nM. Like other HDAC inhibitors, chlamydocin induces the accumulation of hyperacetylated histones H3 and H4 in A2780 ovarian cancer cells, increases the expression of p21(cip1/waf1), and causes an accumulation of cells in G(2)/M phase of the cell cycle. In addition, chlamydocin induces apoptosis by activating caspase-3, which in turn leads to the cleavage of p21(cip1/waf1) into a 15-kDa breakdown product and drives cells from growth arrest into apoptosis. Concomitant with the activation of caspase-3 and cleavage of p21(cip1/waf1), chlamydocin decreases the protein level of survivin, a member of the inhibitor of apoptosis protein family that is selectively expressed in tumors. Although our data indicate a potential link between degradation of survivin and activation of the apoptotic pathway induced by HDAC inhibitors, stable overexpression of survivin does not suppress the activation of caspase-3 or cleavage of p21(cip1/waf1) induced by chlamydocin treatment. The decrease of survivin protein level is mediated by degradation via proteasomes since it can be inhibited by specific proteasome inhibitors. Taken together, our results show that induction of apoptosis by chlamydocin involves caspase-dependent cleavage of p21(cip1/waf1), which is strikingly associated with proteasome-mediated degradation of survivin.

  14. Novel thiol-based histone deacetylase inhibitors bearing 3-phenyl-1H-pyrazole-5-carboxamide scaffold as surface recognition motif: Design, synthesis and SAR study.

    PubMed

    Wen, Jiachen; Niu, Qun; Liu, Jiang; Bao, Yu; Yang, Jinyu; Luan, Shenglin; Fan, Yinbo; Liu, Dan; Zhao, Linxiang

    2016-01-15

    A series of novel thiol-based histone deacetylase (HDAC) inhibitors bearing 3-phenyl-1H-pyrazole-5-carboxamide scaffold as surface recognition motif was designed, synthesized, and evaluated for their HDAC inhibition activity. Among them, 15j (IC50=0.08μM) was identified as a better inhibitor than Vorinostat (IC50=0.25μM) against total HDACs. In addition, Structure-activity relationships (SAR) analyses indicated that (i) compounds with different substituents on pyrazole N-1 position exhibited superior activities than those on pyrazole N-2 position, (ii) variation of functional groups on N-1'-alkyl chain terminus followed the trends of carboxyl group>hydroxyl group≫alkyl group, and (iii) methylation on pyrazole C-4 position diminished the HDAC inhibition activity. The SAR will guide us to further refine compounds bearing 3-phenyl-1H-pyrazole-5-carboxamide scaffold to achieve better HDAC inhibitors.

  15. Carbocysteine restores steroid sensitivity by targeting histone deacetylase 2 in a thiol/GSH-dependent manner.

    PubMed

    Song, Yun; Lu, Hao-Zhong; Xu, Jian-Rong; Wang, Xiao-Lin; Zhou, Wei; Hou, Li-Na; Zhu, Liang; Yu, Zhi-Hua; Chen, Hong-Zhuan; Cui, Yong-Yao

    2015-01-01

    Steroid insensitivity is commonly observed in patients with chronic obstructive pulmonary disease. Here, we report the effects and mechanisms of carbocysteine (S-CMC), a mucolytic agent, in cellular and animal models of oxidative stress-mediated steroid insensitivity. The following results were obtained: oxidative stress induced higher levels of interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-α), which are insensitive to dexamethasone (DEX). The failure of DEX was improved by the addition of S-CMC by increasing histone deacetylase 2 (HDAC2) expression/activity. S-CMC also counteracted the oxidative stress-induced increase in reactive oxygen species (ROS) levels and decreases in glutathione (GSH) levels and superoxide dismutase (SOD) activity. Moreover, oxidative stress-induced events were decreased by the thiol-reducing agent dithiothreitol (DTT), enhanced by the thiol-oxidizing agent diamide, and the ability of DEX was strengthened by DTT. In addition, the oxidative stress-induced decrease in HDAC2 activity was counteracted by S-CMC by increasing thiol/GSH levels, which exhibited a direct interaction with HDAC2. S-CMC treatment increased HDAC2 recruitment and suppressed H4 acetylation of the IL-8 promoter, and this effect was further ablated by addition of buthionine sulfoximine, a specific inhibitor of GSH synthesis. Our results indicate that S-CMC restored steroid sensitivity by increasing HDAC2 expression/activity in a thiol/GSH-dependent manner and suggest that S-CMC may be useful in a combination therapy with glucocorticoids for treatment of steroid-insensitive pulmonary diseases.

  16. Inhibition of class I histone deacetylases unveils a mitochondrial signature and enhances oxidative metabolism in skeletal muscle and adipose tissue.

    PubMed

    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

    2013-03-01

    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-1α, 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-1α action in skeletal muscle and enhanced PPARγ/PGC-1α 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.

  17. An estrogen-responsive element-targeted histone deacetylase enzyme has an antiestrogen activity that differs from that of hydroxytamoxifen.

    PubMed

    Demirpence, Ediz; Semlali, Abdelhabib; Oliva, Joan; Balaguer, Patrick; Badia, Eric; Duchesne, Marie-Josèphe; Nicolas, Jean-Claude; Pons, Michel

    2002-11-15

    We showed previously that prolonged treatment of a MCF-7-derived cell line with hydroxytamoxifen (OHT) induces the irreversible silencing of some estrogen-responsive genes, whereas OHT-resistant cell growth appears simultaneously (E. Badia et al., Cancer Res., 60: 4130-4138, 2000). Based on the hypothesis that particular gene silencings could be involved in triggering the resistance phenomenon, we focused our study on the mechanism of OHT-induced silencing. More precisely, we wished to determine to what extent the recruited histone deacetylase (HDAC) activity, which is known to be involved in the repressive effect induced by antagonist ligands of nuclear receptors, could participate in various aspects of OHT effects, particularly in gene silencing. A fusion protein (HDAC-EG) of human HDAC1 fused with the estrogen receptor DNA-binding domain and the glucocorticoid receptor ligand-binding domain allowed targeting of chimeric HDAC1 activity on estrogen-responsive elements (EREs) in the presence of glucocorticoid ligands. When HDAC-EG was transiently expressed in HeLa cells together with estrogen receptor, an antiestrogen-like effect was obtained on an ERE-controlled luciferase reporter gene in the presence of agonist or antagonist glucocorticoids. In MCF-7-derived cells stably expressing HDAC-EG and an estrogen-regulated luciferase, liganded HDAC-EG again produced an antiestrogenic effect on expression of natural estrogen-regulated genes such as pS2, progesterone receptor, and cathepsin D and cell growth together with chimeric luciferase gene expression. However, a prolonged HDAC-EG-mediated antiestrogen effect did not lead to irreversible luciferase gene silencing, as OHT does. It nevertheless accelerated the OHT-driven phenomenon. The antiestrogen effect of OHT thus differs from that of an ERE-targeted HDAC1 activity that might participate in irreversible silencing but is not sufficient to trigger it.

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

    PubMed Central

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

    2013-01-01

    During hemodynamic stress, catecholamines and neurohumoral stimuli may induce co-activation of Gq-coupled receptors and β-adrenergic receptors (β-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 β-AR stimulation and its cross-interaction with Gq signaling in adult cardiac myocytes. Here, we evaluate the potential cross-talk between Gq-driven and β-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 β-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 β-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 β-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

  19. Design, synthesis, and antitumor evaluation of histone deacetylase inhibitors with l-phenylglycine scaffold

    PubMed Central

    Zhang, Yingjie; Li, Xiaoguang; Hou, Jinning; Huang, Yongxue; Xu, Wenfang

    2015-01-01

    In our previous research, a novel series of histone deacetylase (HDAC) inhibitors with l-phenylglycine scaffold were designed and synthesized, among which amides D3 and D7 and ureido D18 were far superior to the positive control (suberoylanilide hydroxamic acid [SAHA]) in HDAC inhibition, but were only comparable to SAHA in antiproliferation on tumor cell lines. Herein, further structural derivation of lead compounds D3, D7, and D18 was carried out to improve their cellular activities. Most of our newly synthesized compounds exhibited more potent HDAC inhibitory activities than the positive control SAHA, and several derivatives were even better than their parent compounds. However, compared with SAHA and our lead compounds, only secondary amine series compounds exhibited improved antiproliferative activities, likely due to their appropriate topological polar surface area values and cell permeabilities. In a human histiocytic lymphoma (U937) xenograft model, the most potent secondary amine 9d exhibited similar in vivo antitumor activity to that of SAHA. PMID:26504374

  20. Histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA)-mediated correction of α1-antitrypsin deficiency.

    PubMed

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

    2012-11-02

    α1-Antitrypsin (α1AT) deficiency (α1ATD) is a consequence of defective folding, trafficking, and secretion of α1AT in response to a defect in its interaction with the endoplasmic reticulum proteostasis machineries. The most common and severe form of α1ATD is caused by the Z-variant and is characterized by the accumulation of α1AT polymers in the endoplasmic reticulum of the liver leading to a severe reduction (>85%) of α1AT in the serum and its anti-protease activity in the lung. In this organ α1AT is critical for ensuring tissue integrity by inhibiting neutrophil elastase, a protease that degrades elastin. Given the limited therapeutic options in α1ATD, a more detailed understanding of the folding and trafficking biology governing α1AT biogenesis and its response to small molecule regulators is required. Herein we report the correction of Z-α1AT 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-α1AT secretion and serpin activity to a level 50% that observed for wild-type α1AT. These data suggest that HDAC activity can influence Z-α1AT protein traffic and that SAHA may represent a potential therapeutic approach for α1ATD and other protein misfolding diseases.

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

    SciTech Connect

    Ruijter, Annemieke J.M. de; Kemp, Stephan . E-mail: a.b.vankuilenburg@amc.uva.nl

    2005-10-01

    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.

  2. Curcumin and hydroxamate-derivative (PCI-34058) interfere with histone deacetylase I catalytic core Asp-His charge relay system: atomistic simulation studies.

    PubMed

    Omotuyi, I O; Abiodun, M O; Komolafe, K; Ejelonu, O C; Olusanya, O

    2015-05-01

    Histone deacetylases (HDACs) are representative targets for the natural and synthetic chemicals used to transform cells to confer antitumor properties. In the current study, curcumin and hydroxamate-derivative PCI-34058-bound HDAC1 were subjected to atomistic simulation. The results support the view that fitting of curcumin and PCI-34058 within the HDAC1 pocket depends on extensive interactions between the aromatic moieties of the inhibitors and the extensive network of aromatic amino acid side chains lining the pocket of HDAC1. The interaction forces a local perturbation of the coiled structures connecting the pocket residues resulting in ligand-induced tightening of the pocket. In addition to the competitive occupancy of the histone-acetyl-lysine binding pocket by the inhibitors, interference with the in-pocket aspartate-histidine (ASP-HIS) charge relay system was also observed in inhibitor-bound HDAC1 systems. In conclusion, curcumin and PCI-34058-mediated ligand-dependent HDAC1 tunnel closure interferes negatively with the ASP-HIS charge relay system in HDAC1. Future design of HDAC inhibitors may benefit from optimizing competitive interaction with the ligand site and interference with the charge relay system.

  3. cAMP signaling increases histone deacetylase 8 expression via the Epac2–Rap1A–Akt pathway in H1299 lung cancer cells

    PubMed Central

    Park, Ji-Yeon; Juhnn, Yong-Sung

    2017-01-01

    This study was performed to investigate the signaling pathway that mediates cyclic AMP (cAMP)-induced inhibition of histone deacetylase 8 (HDAC8) degradation, and the effect and underlying mechanisms of the resulting increase in HDAC8 expression on cisplatin-induced apoptosis in lung cancer cells. cAMP signaling increased HDAC8 expression via a protein kinase A (PKA)-independent pathway in H1299 non-small cell lung cancer cells. However, treatment with a selective activator of an exchange protein that was activated by cAMP (Epac) increased HDAC8 expression, and Epac2 inhibition abolished the isoproterenol (ISO)-induced increase in HDAC8 expression. ISO and the Epac activator activated Rap1, and Rap1A activation increased HDAC8 expression; moreover, inhibition of Rap1A with a dominant negative Rap1A or by shRNA-mediated knockdown abolished the ISO-induced increase in HDAC8 expression. Activation of cAMP signaling and Rap1A decreased the activating phosphorylation of Akt. Akt inhibition with a pharmacological inhibitor or expression of a dominant negative Akt inhibited the MKK4/JNK pathway and increased HDAC8 expression. The Akt inhibitor-induced increase in HDAC8 expression was abolished by pretreatment with proteasomal or lysosomal inhibitors. The ISO treatment increased cisplatin-induced apoptosis, which was abolished by HDAC8 knockdown. Exogenous HDAC8 expression increased cisplatin-induced apoptosis and decreased TIPRL expression, and the knockdown of TIPRL increased the apoptosis of cisplatin-treated cells. The ISO treatment decreased cisplatin-induced transcription of the TIPRL gene in a HDAC8-dependent manner. In conclusion, the Epac–Rap1–Akt pathway mediates cAMP signaling-induced inhibition of JNK-dependent HDAC8 degradation, and the resulting HDAC8 increase augments cisplatin-induced apoptosis by repressing TIPRL expression in H1299 lung cancer cells. PMID:28232663

  4. cAMP signaling increases histone deacetylase 8 expression via the Epac2-Rap1A-Akt pathway in H1299 lung cancer cells.

    PubMed

    Park, Ji-Yeon; Juhnn, Yong-Sung

    2017-02-24

    This study was performed to investigate the signaling pathway that mediates cyclic AMP (cAMP)-induced inhibition of histone deacetylase 8 (HDAC8) degradation, and the effect and underlying mechanisms of the resulting increase in HDAC8 expression on cisplatin-induced apoptosis in lung cancer cells. cAMP signaling increased HDAC8 expression via a protein kinase A (PKA)-independent pathway in H1299 non-small cell lung cancer cells. However, treatment with a selective activator of an exchange protein that was activated by cAMP (Epac) increased HDAC8 expression, and Epac2 inhibition abolished the isoproterenol (ISO)-induced increase in HDAC8 expression. ISO and the Epac activator activated Rap1, and Rap1A activation increased HDAC8 expression; moreover, inhibition of Rap1A with a dominant negative Rap1A or by shRNA-mediated knockdown abolished the ISO-induced increase in HDAC8 expression. Activation of cAMP signaling and Rap1A decreased the activating phosphorylation of Akt. Akt inhibition with a pharmacological inhibitor or expression of a dominant negative Akt inhibited the MKK4/JNK pathway and increased HDAC8 expression. The Akt inhibitor-induced increase in HDAC8 expression was abolished by pretreatment with proteasomal or lysosomal inhibitors. The ISO treatment increased cisplatin-induced apoptosis, which was abolished by HDAC8 knockdown. Exogenous HDAC8 expression increased cisplatin-induced apoptosis and decreased TIPRL expression, and the knockdown of TIPRL increased the apoptosis of cisplatin-treated cells. The ISO treatment decreased cisplatin-induced transcription of the TIPRL gene in a HDAC8-dependent manner. In conclusion, the Epac-Rap1-Akt pathway mediates cAMP signaling-induced inhibition of JNK-dependent HDAC8 degradation, and the resulting HDAC8 increase augments cisplatin-induced apoptosis by repressing TIPRL expression in H1299 lung cancer cells.

  5. Histone deacetylases: revealing the molecular base of dimorphism in pathogenic fungi

    PubMed Central

    Elías-Villalobos, Alberto; Helmlinger, Dominique; Ibeas, José I.

    2015-01-01

    Fungi, as every living organism, interact with the external world and have to adapt to its fluctuations. For pathogenic fungi, such interaction involves adapting to the hostile environment of their host. Survival depends on the capacity of fungi to detect and respond to external stimuli, which is achieved through a tight and efficient genetic control. Chromatin modifications represent a well-known layer of regulation that controls gene expression in response to environmental signals. However, less is known about the chromatin modifications that are involved in fungal virulence and the specific cues and signalling pathways that target chromatin modifications to specific genes. In a recently published study, our research group identified one such regulatory pathway. We demonstrated that the histone deacetylase (HDAC) Hos2 is involved in yeast-to-hyphal transition (dimorphism) and it is associated with the virulence of the maize pathogen Ustilago maydis, the causative agent of smut disease in corn. Hos2 activates mating-type genes by directly binding to their gene bodies. Furthermore, Hos2 acts downstream of the nutrient-sensing cyclic AMP-Protein Kinase A pathway. We also found that another HDAC, Clr3, contributes to this regulation, possibly in cooperation with Hos2. As a whole, our data suggest that there is a direct link between changes in the environment and acetylation of nucleosomes within certain genes. We propose that histone acetylation is critical to the proper timing and induction of transcription of the genes encoding factors that coordinate changes in morphology with pathogenesis.

  6. The histone deacetylase inhibitor valproic acid enhances acquisition, extinction, and reconsolidation of conditioned fear.

    PubMed

    Bredy, Timothy W; Barad, Mark

    2008-01-01

    Histone modifications contribute to the epigenetic regulation of gene expression, a process now recognized to be important for the consolidation of long-term memory. Valproic acid (VPA), used for many years as an anticonvulsant and a mood stabilizer, has effects on learning and memory and enhances the extinction of conditioned fear through its function as a histone deacetylase inhibitor (HDAC). Here we report that VPA enhances long-term memory for both acquisition and extinction of cued-fear. Interestingly, VPA enhances extinction, but also enhances renewal of the original conditioned fear when tested in a within-subjects design. This effect appears to be related to a reconsolidation-like process since a single CS reminder in the presence of VPA can enhance long-term memory for the original fear in the context in which fear conditioning takes place. We also show that by modifying the intertrial interval during extinction training, VPA can strengthen reconsolidation of the original fear memory or enhance long-term memory for extinction such that it becomes independent of context. These findings have important implications for the use of HDAC inhibitors as adjuncts to behavior therapy in the treatment of phobia and related anxiety disorders.

  7. Histone Deacetylases Exert Class-Specific Roles in Conditioning the Brain and Heart Against Acute Ischemic Injury

    PubMed Central

    Aune, Sverre E.; Herr, Daniel J.; Kutz, Craig J.; Menick, Donald R.

    2015-01-01

    Ischemia-reperfusion (IR) injury comprises a significant portion of morbidity and mortality from heart and brain diseases worldwide. This enduring clinical problem has inspired myriad reports in the scientific literature of experimental interventions seeking to elucidate the pathology of IR injury. Elective cardiac surgery presents perhaps the most viable scenario for protecting the heart and brain from IR injury due to the opportunity to condition the organs prior to insult. The physiological parameters for the preconditioning of vital organs prior to insult through mechanical and pharmacological maneuvers have been heavily examined. These investigations have revealed new insights into how preconditioning alters cellular responses to IR injury. However, the promise of preconditioning remains unfulfilled at the clinical level, and research seeking to implicate cell signals essential to this protection continues. Recent discoveries in molecular biology have revealed that gene expression can be controlled through posttranslational modifications, without altering the chemical structure of the genetic code. In this scenario, gene expression is repressed by enzymes that cause chromatin compaction through catalytic removal of acetyl moieties from lysine residues on histones. These enzymes, called histone deacetylases (HDACs), can be inhibited pharmacologically, leading to the de-repression of protective genes. The discovery that HDACs can also alter the function of non-histone proteins through posttranslational deacetylation has expanded the potential impact of HDAC inhibitors for the treatment of human disease. HDAC inhibitors have been applied in a very small number of experimental models of IR. However, the scientific literature contains an increasing number of reports demonstrating that HDACs converge on preconditioning signals in the cell. This review will describe the influence of HDACs on major preconditioning signaling pathways in the heart and brain. PMID

  8. A seasonal switch in histone deacetylase gene expression in the hypothalamus and their capacity to modulate nuclear signaling pathways.

    PubMed

    Stoney, Patrick N; Rodrigues, Diana; Helfer, Gisela; Khatib, Thabat; Ashton, Anna; Hay, Elizabeth A; Starr, Robert; Kociszewska, Dagmara; Morgan, Peter; McCaffery, Peter

    2017-03-01

    Seasonal animals undergo changes in physiology and behavior between summer and winter conditions. These changes are in part driven by a switch in a series of hypothalamic genes under transcriptional control by hormones and, of recent interest, inflammatory factors. Crucial to the control of transcription are histone deacetylases (HDACs), generally acting to repress transcription by local histone modification. Seasonal changes in hypothalamic HDAC transcripts were investigated in photoperiod-sensitive F344 rats by altering the day-length (photoperiod). HDAC4, 6 and 9 were found to change in expression. The potential influence of HDACs on two hypothalamic signaling pathways that regulate transcription, inflammatory and nuclear receptor signaling, was investigated. For inflammatory signaling the focus was on NF-κB because of the novel finding made that its expression is seasonally regulated in the rat hypothalamus. For nuclear receptor signaling it was discovered that expression of retinoic acid receptor beta was regulated seasonally. HDAC modulation of NF-κB-induced pathways was examined in a hypothalamic neuronal cell line and primary hypothalamic tanycytes. HDAC4/5/6 inhibition altered the control of gene expression (Fos, Prkca, Prkcd and Ptp1b) by inducers of NF-κB that activate inflammation. These inhibitors also modified the action of nuclear receptor ligands thyroid hormone and retinoic acid. Thus seasonal changes in HDAC4 and 6 have the potential to epigenetically modify multiple gene regulatory pathways in the hypothalamus that could act to limit inflammatory pathways in the hypothalamus during long-day summer-like conditions.

  9. Histone deacetylase inhibitors: an overview of the clinical studies in solid tumors.

    PubMed

    Slingerland, Marije; Guchelaar, Henk-Jan; Gelderblom, Hans

    2014-02-01

    The histone deacetylase inhibitors (HDACi) are a group of small molecules that target histone deacetylases (HDACs) by inhibiting their activity. HDACi have a long history of use in neurology and psychiatry as antiepileptics and mood stabilizers. More recently, they have been investigated as possible treatments for cancer. HDACi have undergone rapid clinical development in recent years, on the basis of their preclinical in-vitro and in-vivo antitumor activity in hematological malignancies and solid tumors. Many HDACi have entered phase I-III clinical trials. Among the HDACi, vorinostat and romidepsin are currently the most extensively studied. In 2006 and 2009, respectively, they received approval by the United States Food and Drug Administration for treatment of cutaneous T-cell lymphoma and romidepsin for the treatment of peripheral T-cell lymphoma. Other HDACi, such as panobinostat and valproic acid, also demonstrated activity as therapeutic anticancer agents. In this article we give an overview of the clinical studies of HDACi in solid tumors. We start with a short description of the working mechanism of HDACi in general.

  10. Anti-breast cancer effects of histone deacetylase inhibitors and calpain inhibitor.

    PubMed

    Mataga, Megan A; Rosenthal, Shoshana; Heerboth, Sarah; Devalapalli, Amrita; Kokolus, Shannon; Evans, Leah R; Longacre, McKenna; Housman, Genevieve; Sarkar, Sibaji

    2012-07-01

    Development of new breast cancer therapies is needed, particularly as cells become refractory or develop increased drug resistance. In an effort to develop such treatments, class I and II histone deacetylases (HDACs), alone and in combination with other cytotoxic agents, are currently in clinical trial. Herein, we discuss the effects of histone deacetylase inhibitors (HDACi) when used in combination with calpeptin, an inhibitor of the regulatory protease, calpain. We present results of study in two breast cancer cells lines with distinct characteristics: MDA-MB-231 and MCF-7. When used in combination with calpeptin, two chemically distinct HDACi significantly inhibited growth and increased cell death by inducing cell-cycle arrest and apoptosis. MCF-7 cells exhibited a greater proportion of arrest at the G(1) phase, whereas triple-negative MDA-MB-231 cells exhibited increased cell cycle arrest at the S phase. Methylation of the imprinted and silenced proapoptoic tumor suppressor gene aplasia Ras homolog member I (ARHI) was reduced in both cell lines after treatment with HDACi. However, it was only re-expressed on such treatment in MDA-MB-231 cells, suggesting that re-expression operates under differential mechanisms in these two cell lines. Collectively, these results showed that the combination of HDACi and calpeptin inhibited the growth of two distinctly different types of breast cancer cells and could have wide clinical applications, though the mechanisms of inhibition are possibly different.

  11. Largazole and Analogues with Modified Metal-Binding Motifs Targeting Histone Deacetylases: Synthesis and Biological Evaluation

    PubMed Central

    Bhansali, Pravin; Hanigan, Christin L.; Casero, Robert A.; Tillekeratne, L. M. Viranga

    2011-01-01

    The histone deacetylase inhibitor, largazole 1 was synthesized by a convergent approach which involved several efficient and high yielding single pot multistep protocols. Initial attempts using t-butyl as thiol protecting group proved problematic and synthesis was accomplished by switching to trityl protecting group. This synthetic protocol provides a convenient approach to many new largazole analogues. Three side chain analogues with multiple heteroatoms for chelation with Zn2+ were synthesized and their biological activities were evaluated. They were less potent than largazole 1 in growth inhibition of HCT116 colon carcinoma cell line and in inducing increases in global H3 acetylation. Largazole 1 and the three side chain analogues had no effect on HDAC6 as indicated by the lack of increased acetylation of α-tubulin. PMID:21936551

  12. Inhibitors of Histone Deacetylases for Radiosensitization of Prostate Cancer

    DTIC Science & Technology

    2006-04-01

    was used as a loading control. Effects of candidate HDACIs and siRNA HDAC isoforms on radiation clonogenic survivals: Previously, HDAC inhibitory...by candidate HDACIs , we focused on class I HDAC isoforms. In vitro HDAC activity assays were performed using immunoprecipitates (HDAC1, HDAC2, HDAC3

  13. Early life stress triggers sustained changes in histone deacetylase expression and histone H4 modifications that alter responsiveness to adolescent antidepressant treatment

    PubMed Central

    Levine, Amir; Worrell, Trent R.; Zimnisky, Ross; Schmauss, Claudia

    2011-01-01

    Early life stress can elicit long-lasting changes in gene expression and behavior. Recent studies on rodents suggest that these lasting effects depend on the genetic background. Whether epigenetic factors also play a role remains to be investigated. Here we exposed the stress-susceptible mouse strain Balb/c and the more resilient strain C57Bl/6 to a powerful early life stress paradigm, infant maternal separation. In Balb/c mice, infant maternal separation led to decreased expression of mRNA encoding the histone deacetylases (HDACs) 1, 3, 7, 8, and 10 in the forebrain neocortex in adulthood, an effect accompanied by increased expression of acetylated histone H4 proteins, especially acetylated H4K12 protein. These changes in HDAC expression and histone modifications were not detected in C57Bl/6 mice exposed to early life stress. Moreover, a reversal of the H4K12 hyperacetylation detected in infant maternally separated Balb/c mice (achieved with chronic adolescent treatment with a low dose of theophylline that only activates HDACs) worsened the abnormal emotional phenotype resulting from this early life stress exposure. In contrast, fluoxetine, a drug with potent antidepressant efficacy in infant maternally separated Balb/c mice, potentiated all histone modifications triggered by early life stress. Moreover, in non-stressed Balb/c mice, co-administration of an HDAC inhibitor and fluoxetine, but not fluoxetine alone, elicited antidepressant effects and also triggered changes in histone H4 expression that were similar to those provoked by fluoxetine treatment of mice exposed to early life stress. These results suggest that Balb/c mice develop epigenetic modifications after early life stress exposure that, in terms of the emotive phenotype, are of adaptive nature, and that enhance the efficacy of antidepressant drugs. PMID:21964251

  14. Chromium Cross-Links Histone Deacetylase 1-DNA Methyltransferase 1 Complexes to Chromatin, Inhibiting Histone-Remodeling Marks Critical for Transcriptional Activation▿

    PubMed Central

    Schnekenburger, Michael; Talaska, Glenn; Puga, Alvaro

    2007-01-01

    Transcriptional regulation of gene expression requires posttranslational modification of histone proteins, which, in concert with chromatin-remodeling factors, modulate chromatin structure. Exposure to environmental agents may interfere with specific histone modifications and derail normal patterns of gene expression. To test this hypothesis, we coexposed cells to binary mixtures of benzo[a]pyrene (B[a]P), an environmental procarcinogen that activates Cyp1a1 transcriptional responses mediated by the aryl hydrocarbon receptor (AHR), and chromium, a carcinogenic heavy metal that represses B[a]P-inducible AHR-mediated gene expression. We show that chromium cross-links histone deacetylase 1-DNA methyltransferase 1 (HDAC1-DNMT1) complexes to Cyp1a1 promoter chromatin and inhibits histone marks induced by AHR-mediated gene transactivation, including phosphorylation of histone H3 Ser-10, trimethylation of H3 Lys-4, and various acetylation marks in histones H3 and H4. These changes inhibit RNA polymerase II recruitment without affecting the kinetics of AHR DNA binding. HDAC1 and DNMT1 inhibitors or depletion of HDAC1 or DNMT1 with siRNAs blocks chromium-induced transcriptional repression by decreasing the interaction of these proteins with the Cyp1a1 promoter and allowing histone acetylation to proceed. By inhibiting Cyp1a1 expression, chromium stimulates the formation of B[a]P DNA adducts. Epigenetic modification of gene expression patterns may be a key element of the developmental and carcinogenic outcomes of exposure to chromium and to other environmental agents. PMID:17682057

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

    SciTech Connect

    Fujii, Seiko; Okinaga, Toshinori; Ariyoshi, Wataru; Takahashi, Osamu; Iwanaga, Kenjiro; Nishino, Norikazu; Tominaga, Kazuhiro; Nishihara, Tatsuji

    2013-05-10

    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.

  16. Histone deacetylase inhibitors promote the tumoricidal effect of HAMLET.

    PubMed

    Brest, Patrick; Gustafsson, Mattias; Mossberg, Ann-Kristin; Gustafsson, Lotta; Duringer, Caroline; Hamiche, Ali; Svanborg, Catharina

    2007-12-01

    Histone deacetylase inhibitors (HDIs) and HAMLET (human alpha-lactalbumin made lethal to tumor cells) interact with histones, modify the structure of chromatin, and trigger tumor cell death. This study investigated how the combination of HDIs and HAMLET influences cell viability, histone acetylation, and DNA integrity. The pretreatment of tumor cells with HDIs was shown to enhance the lethal effect of HAMLET and the histone hyperacetylation response to HDIs increased even further after HAMLET treatment. HDIs and HAMLET were shown to target different histone domains as HAMLET bound tailless core histones, whereas HDIs modify the acetylation of the histone tail. DNA damage in response to HAMLET was increased by HDIs. The DNA repair response (p21WAFI expression) was induced by both agonists but abolished when the two agonists were combined. The results suggest that the synergy of HDIs and HAMLET is based on different but converging death pathways, both involving chromatin alterations. We speculate that HAMLET and HDIs might be combined to promote tumor cell death in vivo.

  17. The Histone Deacetylase Inhibitor Suberoylanilide Hydroxamic Acid Alleviates Salinity Stress in Cassava

    PubMed Central

    Patanun, Onsaya; Ueda, Minoru; Itouga, Misao; Kato, Yukari; Utsumi, Yoshinori; Matsui, Akihiro; Tanaka, Maho; Utsumi, Chikako; Sakakibara, Hitoshi; Yoshida, Minoru; Narangajavana, Jarunya; Seki, Motoaki

    2017-01-01

    Cassava (Manihot esculenta Crantz) demand has been rising because of its various applications. High salinity stress is a major environmental factor that interferes with normal plant growth and limits crop productivity. As well as genetic engineering to enhance stress tolerance, the use of small molecules is considered as an alternative methodology to modify plants with desired traits. The effectiveness of histone deacetylase (HDAC) inhibitors for increasing tolerance to salinity stress has recently been reported. Here we use the HDAC inhibitor, suberoylanilide hydroxamic acid (SAHA), to enhance tolerance to high salinity in cassava. Immunoblotting analysis reveals that SAHA treatment induces strong hyper-acetylation of histones H3 and H4 in roots, suggesting that SAHA functions as the HDAC inhibitor in cassava. Consistent with increased tolerance to salt stress under SAHA treatment, reduced Na+ content and increased K+/Na+ ratio were detected in SAHA-treated plants. Transcriptome analysis to discover mechanisms underlying salinity stress tolerance mediated through SAHA treatment reveals that SAHA enhances the expression of 421 genes in roots under normal condition, and 745 genes at 2 h and 268 genes at 24 h under both SAHA and NaCl treatment. The mRNA expression of genes, involved in phytohormone [abscisic acid (ABA), jasmonic acid (JA), ethylene, and gibberellin] biosynthesis pathways, is up-regulated after high salinity treatment in SAHA-pretreated roots. Among them, an allene oxide cyclase (MeAOC4) involved in a crucial step of JA biosynthesis is strongly up-regulated by SAHA treatment under salinity stress conditions, implying that JA pathway might contribute to increasing salinity tolerance by SAHA treatment. Our results suggest that epigenetic manipulation might enhance tolerance to high salinity stress in cassava. PMID:28119717

  18. Nitric oxide determines mesodermic differentiation of mouse embryonic stem cells by activating class IIa histone deacetylases: potential therapeutic implications in a mouse model of hindlimb ischemia.

    PubMed

    Spallotta, Francesco; Rosati, Jessica; Straino, Stefania; Nanni, Simona; Grasselli, Annalisa; Ambrosino, Valeria; Rotili, Dante; Valente, Sergio; Farsetti, Antonella; Mai, Antonello; Capogrossi, Maurizio C; Gaetano, Carlo; Illi, Barbara

    2010-03-31

    In human endothelial cells, nitric oxide (NO) results in class IIa histone deacetylases (HDACs) activation and marked histone deacetylation. It is unknown whether similar epigenetic events occur in embryonic stem cells (ESC) exposed to NO and how this treatment could influence ESC therapeutic potential during tissue regeneration.This study reports that the NO-dependent class IIa HDACs subcellular localization and activity decreases the global acetylation level of H3 histones in ESC and that this phenomenon is associated with the inhibition of Oct4, Nanog, and KLF4 expression. Further, a NO-induced formation of macromolecular complexes including HDAC3, 4, 7, and protein phosphatase 2A (PP2A) have been detected. These processes correlated with the expression of the mesodermal-specific protein brachyury (Bry) and the appearance of several vascular and skeletal muscle differentiation markers. These events were abolished by the class IIa-specific inhibitor MC1568 and by HDAC4 or HDAC7 short interfering RNA (siRNA). The ability of NO to induce mesodermic/cardiovascular gene expression prompted us to evaluate the regenerative potential of these cells in a mouse model of hindlimb ischemia. We found that NO-treated ESCs injected into the cardiac left ventricle selectively localized in the ischemic hindlimb and contributed to the regeneration of muscular and vascular structures. These findings establish a key role for NO and class IIa HDACs modulation in ESC mesodermal commitment and enhanced regenerative potential in vivo.

  19. Inhibition of Histone Deacetylase Activity in Human Endometrial Stromal Cells Promotes Extracellular Matrix Remodelling and Limits Embryo Invasion

    PubMed Central

    Atkinson, Stuart P.; Quiñonero, Alicia; Martínez, Sebastián; Pellicer, Antonio; Simón, Carlos

    2012-01-01

    Invasion of the trophoblast into the maternal decidua is regulated by both the trophoectoderm and the endometrial stroma, and entails the action of tissue remodeling enzymes. Trophoblast invasion requires the action of metalloproteinases (MMPs) to degrade extracellular matrix (ECM) proteins and in turn, decidual cells express tissue inhibitors of MMPs (TIMPs). The balance between these promoting and restraining factors is a key event for the successful outcome of pregnancy. Gene expression is post-transcriptionally regulated by histone deacetylases (HDACs) that unpacks condensed chromatin activating gene expression. In this study we analyze the effect of histone acetylation on the expression of tissue remodeling enzymes and activity of human endometrial stromal cells (hESCs) related to trophoblast invasion control. Treatment of hESCs with the HDAC inhibitor trichostatin A (TSA) increased the expression of TIMP-1 and TIMP-3 while decreased MMP-2, MMP-9 and uPA and have an inhibitory effect on trophoblast invasion. Moreover, histone acetylation is detected at the promoters of TIMP-1 and TIMP-3 genes in TSA-treated. In addition, in an in vitro decidualized hESCs model, the increase of TIMP-1 and TIMP-3 expression is associated with histone acetylation at the promoters of these genes. Our results demonstrate that histone acetylation disrupt the balance of ECM modulators provoking a restrain of trophoblast invasion. These findings are important as an epigenetic mechanism that can be used to control trophoblast invasion. PMID:22291969

  20. Histone deacetylase inhibitors as a tool to up-regulate new fungal biosynthetic products: isolation of EGM-556, a cyclodepsipeptide, from Microascus sp.

    PubMed

    Vervoort, Hélène C; Drašković, Marija; Crews, Phillip

    2011-02-04

    The histone deacetylase (HDAC) inhibitor suberoylanilide hydroxamic acid (SAHA) was used to turn on the biosynthesis of EGM-556, a new cyclodepsipeptide of hybrid biosynthetic origin, isolated from the Floridian marine sediment-derived fungus Microascus sp. The absolute configurations of three chiral centers were determined by Marfey's derivatization. EGM-556 represents one of the few examples in which silent biosynthetic genes, encoding a new secondary metabolite, were activated by means of epigenetic manipulation of the fungal metabolome.

  1. HISTONE DEACETYLASE ACTIVITY AND REACTIVE OXYGEN SPECIES CONTENT IN THE TISSUE CULTURE OF Arabidopsis thaliana UNDER NORMAL CONDITIONS AND DEVELOPMENT OF ACUTE OSMOTIC STRESS.

    PubMed

    Jadko, S I

    2015-01-01

    The possible involvement of histone deacetylase (HDAC) in regulation of ROS content in the tissue culture of Arabidopsis thaliana under normal conditions and under development of acute osmotic stress was studied by using inhibition assay with application of trichostatin A (TSA). It was found that in the tissue culture grown under normal conditions a decrease in HDAC activity by means of TSA led to increase of the ROS content. Similar but more pronounced alterations occurred under stress. At the same time an increase in histone acetyltransferase (HAT) activity was also observed. The possible mechanisms of HDAC and HAT participation in regulation of ROS content by changes in expression of genes that are responsible for ROS production and antioxidant activity are discussed.

  2. A phase II study of the histone deacetylase inhibitor vorinostat combined with tamoxifen for the treatment of patients with hormone therapy-resistant breast cancer

    PubMed Central

    Munster, P N; Thurn, K T; Thomas, S; Raha, P; Lacevic, M; Miller, A; Melisko, M; Ismail-Khan, R; Rugo, H; Moasser, M; Minton, S E

    2011-01-01

    Background: Histone deacetylases (HDACs) are crucial components of the oestrogen receptor (ER) transcriptional complex. Preclinically, HDAC inhibitors can reverse tamoxifen/aromatase inhibitor resistance in hormone receptor-positive breast cancer. This concept was examined in a phase II combination trial with correlative end points. Methods: Patients with ER-positive metastatic breast cancer progressing on endocrine therapy were treated with 400 mg of vorinostat daily for 3 of 4 weeks and 20 mg tamoxifen daily, continuously. Histone acetylation and HDAC2 expression in peripheral blood mononuclear cells were also evaluated. Results: In all, 43 patients (median age 56 years (31–71)) were treated, 25 (58%) received prior adjuvant tamoxifen, 29 (67%) failed one prior chemotherapy regimen, 42 (98%) progressed after one, and 23 (54%) after two aromatase inhibitors. The objective response rate by Response Evaluation Criteria in Solid Tumours criteria was 19% and the clinical benefit rate (response or stable disease >24 weeks) was 40%. The median response duration was 10.3 months (confidence interval: 8.1–12.4). Histone hyperacetylation and higher baseline HDAC2 levels correlated with response. Conclusion: The combination of vorinostat and tamoxifen is well tolerated and exhibits encouraging activity in reversing hormone resistance. Correlative studies suggest that HDAC2 expression is a predictive marker and histone hyperacetylation is a useful pharmacodynamic marker for the efficacy of this combination. PMID:21559012

  3. Histone deacetylase inhibition enhances antimicrobial peptide but not inflammatory cytokine expression upon bacterial challenge

    PubMed Central

    Fischer, Natalie; Sechet, Emmanuel; Friedman, Robin; Amiot, Aurélien; Sobhani, Iradj; Nigro, Giulia; Sansonetti, Philippe J.; Sperandio, Brice

    2016-01-01

    Antimicrobial peptides (AMP) are defense effectors of the innate immunity playing a crucial role in the intestinal homeostasis with commensals and protection against pathogens. Herein we aimed to investigate AMP gene regulation by deciphering specific characteristics allowing their enhanced expression among innate immune genes, particularly those encoding proinflammatory mediators. Our emphasis was on epigenetic regulation of the gene encoding the AMP β-defensin 2 (HBD2), taken as a model of possibly specific induction, upon challenge with a commensal bacterium, compared with the proinflammatory cytokine IL-8. Using an in vitro model of colonic epithelial cells challenged with Escherichia coli K12, we showed that inhibition of histone deacetylases (HDAC) by trichostatin A dramatically enhanced induction of HBD2 expression, without affecting expression of IL-8. This mechanism was supported by an increased phosphorylation of histone H3 on serine S10, preferentially at the HBD2 promoter. This process occurred through activation of the IκB kinase complex, which also led to activation of NF-κB. Moreover, we demonstrated that NF-κB was modified by acetylation upon HDAC inhibition, partly by the histone acetyltransferase p300, and that both NF-κB and p300 supported enhanced induction of HBD2 expression. Furthermore, we identified additional genes belonging to antimicrobial defense and epithelial restitution pathways that showed a similar pattern of epigenetic control. Finally, we confirmed our finding in human colonic primary cells using an ex vivo organoid model. This work opens the way to use epigenetic pharmacology to achieve induction of epithelial antimicrobial defenses, while limiting the deleterious risk of an inflammatory response. PMID:27162363

  4. Spiro[chromane-2,4'-piperidine]-based histone deacetylase inhibitors with improved in vivo activity.

    PubMed

    Thaler, Florian; Varasi, Mario; Carenzi, Giacomo; Colombo, Andrea; Abate, Agnese; Bigogno, Chiara; Boggio, Roberto; Carrara, Simone; Cataudella, Tiziana; Dal Zuffo, Roberto; Reali, Veronica; Vultaggio, Stefania; Dondio, Giulio; Gagliardi, Stefania; Minucci, Saverio; Mercurio, Ciro

    2012-04-01

    A series of spiro[chromane-2,4'-piperidine] derivatives based on a previously published lead benzyl spirocycle 1 and bearing various N-aryl and N-alkylaryl substituents on the piperidine ring were prepared as novel histone deacetylase (HDAC) inhibitors. The compounds were evaluated for their abilities to inhibit nuclear HDACs, their in vitro antiproliferative activities, and in vitro ADME profiles. Based on these activities, 4-fluorobenzyl and 2-phenylethyl spirocycles were selected for further characterization. In vivo pharmacokinetic (PK) studies showed that both compounds exhibit an overall lower clearance rate, an increased half-life, and higher AUCs after intravenous and oral administration than spiropiperidine 1 under the conditions used. The improved PK behavior of these two compounds also correlated with superior in vivo antitumor activity in an HCT-116 xenograft model.

  5. Why Hydroxamates May Not Be the Best Histone Deacetylase Inhibitors--What Some May Have Forgotten or Would Rather Forget?

    PubMed

    Shen, Sida; Kozikowski, Alan P

    2016-01-05

    Hydroxamate-based histone deacetylase inhibitors (HDACIs) have been approved as therapeutic agents by the US Food and Drug Administration for use in oncology applications. While the potential utility of such HDACIs in other areas of medicinal chemistry is tremendous, there are significant concerns that "pan-HDAC inhibitors" may be too broadly acting and/or toxic for clinical use beyond oncology. In addition to the isozyme selectivity challenge, the potential mutagenicity of hydroxamate-containing HDAC inhibitors represents a major hindrance in their application to other therapeutic areas. Herein we report on the mutagenicity of known hydroxamates, discuss the mechanisms responsible for their genotoxicity, and review some of the current alternatives to hydroxamates. We conclude that the hydroxamate group, while providing high-potency HDACIs, is not necessarily the best zinc-binding group for HDACI drug discovery.

  6. Why Hydroxamates May Not Be the Best Histone Deacetylase Inhibitors—What Some May Have Forgotten or Would Rather Forget?

    PubMed Central

    Shen, Sida

    2016-01-01

    Hydroxamate-based histone deacetylase inhibitors (HDACIs) have been approved as therapeutic agents by the US Food and Drug Administration for use in oncology applications. While the potential utility of such HDACIs in other areas of medicinal chemistry is tremendous, there are significant concerns that “pan-HDAC inhibitors” may be too broadly acting and/or toxic for clinical use beyond oncology. In addition to the isozyme selectivity challenge, the potential mutagenicity of hydroxamate-containing HDAC inhibitors represents a major hindrance in their application to other therapeutic areas. Herein we report on the mutagenicity of known hydroxamates, discuss the mechanisms responsible for their genotoxicity, and review some of the current alternatives to hydroxamates. We conclude that the hydroxamate group, while providing high-potency HDACIs, is not necessarily the best zinc-binding group for HDACI drug discovery. PMID:26603496

  7. Neuronal Nitric Oxide Synthase in Neural Stem Cells Induces Neuronal Fate Commitment via the Inhibition of Histone Deacetylase 2

    PubMed Central

    Jin, Xing; Yu, Zhang-Feng; Chen, Fang; Lu, Guang-Xian; Ding, Xin-Yuan; Xie, Lin-Jun; Sun, Jian-Tong

    2017-01-01

    Active adult neurogenesis produces new functional neurons, which replace the lost ones and contribute to brain repair. Promoting neurogenesis may offer a therapeutic strategy for human diseases associated with neurodegeneration. Here, we report that endogenous neuronal nitric oxide synthase (nNOS) for neural stem cells (NSCs) or progenitors positively regulates neurogenesis. nNOS repression exhibits significantly decreased neuronal differentiation and nNOS upregulation promotes neurons production from NSCs. Using a quantitative approach, we show that instructive effect, that is instruction of NSCs to adopt a neuronal fate, contributes to the favorable effect of endogenous nNOS on neurogenesis. Furthermore, nNOS-mediated instruction of neuronal fate commitment is predominantly due to the reduction of histone deacetylase 2 (HDAC2) expression and enzymatic activity. Further investigation will be needed to test whether HDAC2 can serve as a new target for therapeutic intervention of neurodegenerative disorders. PMID:28326018

  8. Suppression of Excessive Histone Deacetylases Activity in Diabetic Hearts Attenuates Myocardial Ischemia/Reperfusion Injury via Mitochondria Apoptosis Pathway

    PubMed Central

    Wu, Yang; Leng, Yan; Meng, Qingtao; Xue, Rui; Zhao, Bo; Zhan, Liying

    2017-01-01

    Background. Histone deacetylases (HDACs) play a pivotal role in signaling modification and gene transcriptional regulation that are essential for cardiovascular pathophysiology. Diabetic hearts with higher HDACs activity were more vulnerable to myocardial ischemia/reperfusion (MI/R) injury compared with nondiabetic hearts. We are curious about whether suppression of excessive HDACs activity in diabetic heart protects against MI/R injury. Methods. Diabetic rats were subjected to 45 min of ischemia, followed by 3 h of reperfusion. H9C2 cardiomyocytes were exposed to high glucose for 24 h, followed by 4 h of hypoxia and 2 h of reoxygenation (H/R). Results. Both MI/R injury and diabetes mellitus elevated myocardium HDACs activity. MI/R induced apoptotic cell death was significantly decreased in diabetic rats treated with HDACs inhibitor trichostatin A (TSA). TSA administration markedly moderated dissipation of mitochondrial membrane potential, protected the integrity of mitochondrial permeability transition pore (mPTP), and decreased cell apoptosis. Notably, cotreatment with Akt inhibitor partly or absolutely inhibited the protective effect of TSA in vivo and in vitro. Furthermore, TSA administration activated Akt/Foxo3a pathway, leading to Foxo3a cytoplasm translocation and attenuation proapoptosis protein Bim expression. Conclusions. Both diabetes mellitus and MI/R injury increased cardiac HDACs activity. Suppression of HDACs activity triggered protective effects against MI/R and H/R injury under hyperglycemia conditions through Akt-modulated mitochondrial apoptotic pathways via Foxo3a/Bim. PMID:28191472

  9. Changes in cardiac Nav1.5 expression, function, and acetylation by pan-histone deacetylase inhibitors.

    PubMed

    Xu, Qin; Patel, Dakshesh; Zhang, Xian; Veenstra, Richard D

    2016-11-01

    Histone deacetylase (HDAC) inhibitors are small molecule anticancer therapeutics that exhibit limiting cardiotoxicities including QT interval prolongation and life-threatening cardiac arrhythmias. Because the molecular mechanisms for HDAC inhibitor-induced cardiotoxicity are poorly understood, we performed whole cell patch voltage-clamp experiments to measure cardiac sodium currents (INa) from wild-type neonatal mouse ventricular or human-induced pluripotent stem cell-derived cardiomyocytes treated with trichostatin A (TSA), vorinostat (VOR), or romidepsin (FK228). All three pan-HDAC inhibitors dose dependently decreased peak INa density and shifted the voltage activation curve 3- to 8-mV positive. Increases in late INa were not observed despite a moderate slowing of the inactivation rate at low activating potentials (<-40 mV). Scn5a mRNA levels were not significantly altered but NaV1.5 protein levels were significantly reduced. Immunoprecipitation with anti-NaV1.5 and Western blotting with anti-acetyl-lysine antibodies indicated that NaV1.5 acetylation is increased in vivo after HDAC inhibition. FK228 inhibited total cardiac HDAC activity with two apparent IC50s of 5 nM and 1.75 μM, consistent with previous findings with TSA and VOR. FK228 also decreased ventricular gap junction conductance (gj), again consistent with previous findings. We conclude that pan-HDAC inhibition reduces cardiac INa density and NaV1.5 protein levels without affecting late INa amplitude and, thus, probably does not contribute to the reported QT interval prolongation and arrhythmias associated with pan-HDAC inhibitor therapies. Conversely, reductions in gj may enhance the occurrence of triggered activity by limiting electrotonic inhibition and, combined with reduced INa, slow myocardial conduction and increase vulnerability to reentrant arrhythmias.

  10. Class I to III histone deacetylases differentially regulate inflammation-induced matrix metalloproteinase 9 expression in primary amnion cells.

    PubMed

    Poljak, Marin; Lim, Ratana; Barker, Gillian; Lappas, Martha

    2014-06-01

    Matrix metalloproteinase (MMP) 9 plays an important role in the degradation of the extracellular matrix in fetal membranes, and pathological activation of MMP-9 can lead to preterm birth. In nongestational tissues, modulation of histone deacetylases (HDACs) regulates MMP-9 expression. The aim of this study was to determine whether class I to III HDACs regulate MMP-9 expression and activity in primary amnion cells. Class I and II HDAC regulation of MMP-9 was assessed using the general class I and II HDAC inhibitors (HDACi) trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA), the class I HDACi MS-275, and the class II HDACi MC1568. Class III HDAC regulation of MMP-9 was assessed using the SIRT1 activators resveratrol and SRT1720 as well as SIRT1 small interfering RNA (siRNA). Primary amnion epithelial cells were incubated with 1 ng/mL interleukin (IL) 1β in the absence or presence of 0.3 μmol/L TSA, 5 μmol/L SAHA, 2.5 μmol/L MS-275, 2.5 μmol/L MC1568, 50 μmol/L resveratrol, or 10 μmol/L SRT1720 for 20 hours. We found that the class I and II HDACi TSA and SAHA and the class II HDACi MC1568 significantly decreased IL-β-induced MMP-9 gene and pro-MMP-9 expression in primary amnion cells. There was, however, no effect of the class I HDACi MS-275 on IL-β-induced MMP-9 expression. On the other hand, inhibition of class III HDAC SIRT1 using siRNA significantly augmented IL-1β-induced MMP-9, and SIRT1 activation using resveratrol and SRT1720 inhibited IL-1β-induced MMP-9 expression. In summary, class I to III HDACs differentially regulate inflammation-induced MMP-9 expression in primary amnion cells.

  11. Characterization and Expression Analysis of Common Bean Histone Deacetylase 6 during Development and Cold Stress Response

    PubMed Central

    Ligaba-Osena, Ayalew; Subramani, Mayavan; Brown, Adrianne; Melmaiee, Kalpalatha; Hossain, Khwaja

    2017-01-01

    Histone deacetylases (HDACs) are important regulators of gene transcription thus controlling multiple cellular processes. Despite its essential role in plants, HDA6 is yet to be validated in common bean. In this study, we show that HDA6 is involved in plant development and stress response. Differential expression of HDA6 was determined in various tissues and the expression was seen to be upregulated with plant age (seedling < flowering < maturity). Higher expression was observed in flowers and pods than in stem, leaf, and root. Upregulation of HDA6 gene during cold stress implies its prominent role in abiotic stress. Furthermore, the HDA6 gene was isolated from three common bean genotypes and sequence analyses revealed homology with functionally characterized homologs in model species. The 53 kDa translated product was detected using an HDA6 specific antibody and recombinant protein overexpressed in Escherichia coli showed HDAC activity in vitro. To our knowledge, this is the first report in the agriculturally important crop common bean describing the functional characterization and biological role of HDA6. PMID:28127547

  12. The histone deacetylase inhibiting drug Entinostat induces lipid accumulation in differentiated HepaRG cells

    PubMed Central

    Nunn, Abigail D. G.; Scopigno, Tullio; Pediconi, Natalia; Levrero, Massimo; Hagman, Henning; Kiskis, Juris; Enejder, Annika

    2016-01-01

    Dietary overload of toxic, free metabolic intermediates leads to disrupted insulin signalling and fatty liver disease. However, it was recently reported that this pathway might not be universal: depletion of histone deacetylase (HDAC) enhances insulin sensitivity alongside hepatic lipid accumulation in mice, but the mechanistic role of microscopic lipid structure in this effect remains unclear. Here we study the effect of Entinostat, a synthetic HDAC inhibitor undergoing clinical trials, on hepatic lipid metabolism in the paradigmatic HepaRG liver cell line. Specifically, we statistically quantify lipid droplet morphology at single cell level utilizing label-free microscopy, coherent anti-Stokes Raman scattering, supported by gene expression. We observe Entinostat efficiently rerouting carbohydrates and free-fatty acids into lipid droplets, upregulating lipid coat protein gene Plin4, and relocating droplets nearer to the nucleus. Our results demonstrate the power of Entinostat to promote lipid synthesis and storage, allowing reduced systemic sugar levels and sequestration of toxic metabolites within protected protein-coated droplets, suggesting a potential therapeutic strategy for diseases such as diabetes and metabolic syndrome. PMID:27320682

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

    PubMed

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

    2014-06-30

    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.

  14. Butyrate upregulates endogenous host defense peptides to enhance disease resistance in piglets via histone deacetylase inhibition

    PubMed Central

    Xiong, Haitao; Guo, Bingxiu; Gan, Zhenshun; Song, Deguang; Lu, Zeqing; Yi, Hongbo; Wu, Yueming; Wang, Yizhen; Du, Huahua

    2016-01-01

    Butyrate has been used to treat different inflammatory disease with positive outcomes, the mechanisms by which butyrate exerts its anti-inflammatory effects remain largely undefined. Here we proposed a new mechanism that butyrate manipulate endogenous host defense peptides (HDPs) which contributes to the elimination of Escherichia coli O157:H7, and thus affects the alleviation of inflammation. An experiment in piglets treated with butyrate (0.2% of diets) 2 days before E. coli O157:H7 challenge was designed to investigate porcine HDP expression, inflammation and E. coli O157:H7 load in feces. The mechanisms underlying butyrate-induced HDP gene expression and the antibacterial activity and bacterial clearance of macrophage 3D4/2 cells in vitro were examined. Butyrate treatment (i) alleviated the clinical symptoms of E. coli O157:H7-induced hemolytic uremic syndrome (HUS) and the severity of intestinal inflammation; (ii) reduced the E. coli O157:H7 load in feces; (iii) significantly upregulated multiple, but not all, HDPs in vitro and in vivo via histone deacetylase (HDAC) inhibition; and (iv) enhanced the antibacterial activity and bacterial clearance of 3D4/2 cells. Our findings indicate that butyrate enhances disease resistance, promotes the clearance of E. coli O157:H7, and alleviates the clinical symptoms of HUS and inflammation, partially, by affecting HDP expression via HDAC inhibition. PMID:27230284

  15. Histone Deacetylase Inhibition Rescues Maternal Deprivation-Induced GABAergic Metaplasticity through Restoration of AKAP Signaling.

    PubMed

    Authement, Michael E; Kodangattil, Jayaraj N; Gouty, Shawn; Rusnak, Milan; Symes, Aviva J; Cox, Brian M; Nugent, Fereshteh S

    2015-06-03

    Adverse early-life experiences such as child neglect and abuse increase the risk of developing addiction and stress-related disorders through alterations in motivational systems including the mesolimbic dopamine (DA) pathway. Here we investigated whether a severe early-life stress (i.e., maternal deprivation, MD) promotes DA dysregulation through an epigenetic impairment of synaptic plasticity within ventral tegmental area (VTA) DA neurons. Using a single 24-hr episode of MD and whole-cell patch clamp recording in rat midbrain slices, we show that MD selectively induces long-term depression (LTD) and shifts spike timing-dependent plasticity (STDP) toward LTD at GABAergic synapses onto VTA DA neurons through epigenetic modifications of postsynaptic scaffolding A-kinase anchoring protein 79/150 (AKAP79/150) signaling. Histone deacetylase (HDAC) inhibition rescues GABAergic metaplasticity and normalizes AKAP signaling in MD animals. MD-induced reversible HDAC-mediated GABAergic dysfunction within the VTA may be a mechanistic link for increased propensity to mental health disorders following MD.

  16. The histone deacetylase inhibiting drug Entinostat induces lipid accumulation in differentiated HepaRG cells

    NASA Astrophysics Data System (ADS)

    Nunn, Abigail D. G.; Scopigno, Tullio; Pediconi, Natalia; Levrero, Massimo; Hagman, Henning; Kiskis, Juris; Enejder, Annika

    2016-06-01

    Dietary overload of toxic, free metabolic intermediates leads to disrupted insulin signalling and fatty liver disease. However, it was recently reported that this pathway might not be universal: depletion of histone deacetylase (HDAC) enhances insulin sensitivity alongside hepatic lipid accumulation in mice, but the mechanistic role of microscopic lipid structure in this effect remains unclear. Here we study the effect of Entinostat, a synthetic HDAC inhibitor undergoing clinical trials, on hepatic lipid metabolism in the paradigmatic HepaRG liver cell line. Specifically, we statistically quantify lipid droplet morphology at single cell level utilizing label-free microscopy, coherent anti-Stokes Raman scattering, supported by gene expression. We observe Entinostat efficiently rerouting carbohydrates and free-fatty acids into lipid droplets, upregulating lipid coat protein gene Plin4, and relocating droplets nearer to the nucleus. Our results demonstrate the power of Entinostat to promote lipid synthesis and storage, allowing reduced systemic sugar levels and sequestration of toxic metabolites within protected protein-coated droplets, suggesting a potential therapeutic strategy for diseases such as diabetes and metabolic syndrome.

  17. Histone deacetylase inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats

    PubMed Central

    Lee, Eunjo; Song, Min-ji; Lee, Hae-Ahm; Kang, Seol-Hee; Kim, Mina; Yang, Eun Kyoung; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung

    2016-01-01

    CG200745 is a novel inhibitor of histone deacetylases (HDACs), initially developed for treatment of various hematological and solid cancers. Because it is water-soluble, it can be administered orally. We hypothesized that the HDAC inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in deoxycorticosterone acetate (DOCA)-induced hypertensive rats. For establishment of hypertension, 40 mg/kg of DOCA was subcutaneously injected four times weekly into Sprague-Dawley rats. All the rats used in this study including those in the sham group had been unilaterally nephrectomized and allowed free access to drinking water containing 1% NaCl. Systolic blood pressure was measured by the tail-cuff method. Blood chemistry including sodium, potassium, glucose, triglyceride, and cholesterol levels was analyzed. Sections of the heart were visualized after trichrome and hematoxylin and eosin stain. The expression of hypertrophic genes such as atrial natriuretic peptide A (Nppa) and atrial natriuretic peptide B (Nppb) in addition to fibrotic genes such as Collagen-1, Collagen-3, connective tissue growth factor (Ctgf), and Fibronectin were measured by quantitative real-time PCR (qRT-PCR). Injection of DOCA increased systolic blood pressure, heart weight, and cardiac fibrosis, which was attenuated by CG200745. Neither DOCA nor CG200745 affected body weight, vascular contraction and relaxation responses, and blood chemistry. Injection of DOCA increased expression of both hypertrophic and fibrotic genes, which was abrogated by CG200745. These results indicate that CG200745 attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats. PMID:27610034

  18. A non-isotopic assay for histone deacetylase activity.

    PubMed

    Hoffmann, K; Brosch, G; Loidl, P; Jung, M

    1999-05-01

    Inhibitors of histone deacetylase (HD) bear great potential as new drugs due to their ability to modulate transcription and to induce apoptosis or differentiation in cancer cells. To study the activity of HD and the effect of potential inhibitors in vitro so far only radio-active assays have existed. For the search of new inhibitors and for the use in HD identification and purification we established a simple, non-radioactive assay that allows screening of large numbers of compounds. The assay is based on an aminocoumarin derivative of an Omega-acetylated lysine as enzyme substrate.

  19. Histone deacetylase inhibitors suppress TF-kappaB-dependent agonist-driven tissue factor expression in endothelial cells and monocytes.

    PubMed

    Wang, Jianguo; Mahmud, Shawn A; Bitterman, Peter B; Huo, Yuqing; Slungaard, Arne

    2007-09-28

    Histone deacetylase inhibitors (HDACi), such as trichostatin A (TSA), can regulate gene expression by promoting acetylation of histones and transcription factors. Human tissue factor (TF) expression is partly governed by a unique, NF-kappaB-related "TF-kappaB" promoter binding site. We find that TSA and four other HDACi (apicidin, MS-275, sodium butyrate, and valproic acid) all inhibit by approximately 90% TF activity and protein level induction in human umbilical vein endothelial cells stimulated by the physiologic agonists tumor necrosis factor (TNF)-alpha, interleukin-1beta, lipopolysaccharide, and HOSCN without affecting expression of the NF-kappaB-regulated adhesion molecules ICAM-1 and E-selectin. TSA and butyrate also blunt TF induction approximately 50% in vitro in peripheral blood mononuclear cells and in vivo in thioglycolate-elicited murine peritoneal macrophages. In human umbilical vein endothelial cells, TSA attenuates by approximately 70% TNF-alpha stimulation of TF mRNA transcription without affecting that of ICAM-1. By electrophoretic mobility shift assay analyses, TNF-alpha and lipopolysaccharide induce strong p65/p50 and p65/c-Rel heterodimer binding to both NF-kappaB and TF-kappaB probes. TSA nearly abolishes TF-kappaB binding without affecting NF-kappaB binding. A chromatin immunoprecipitation assay and a promoter-luciferase reporter system confirm that TSA inhibits TF-kappaB but not NF-kappaB activation. Chromatin immunoprecipitation and small interfering RNA inhibitor studies demonstrate that HDAC3 plays a significant role in TNF-alpha-mediated TF induction. Thus, HDACi transcriptionally inhibit agonist-induced TF expression in endothelial cells and monocytes by a TF-kappaB- and HDAC3-dependent mechanism. We conclude that histone deacetylases, particularly HDAC3, play a hitherto unsuspected role in regulating TF expression and raise the possibility that HDACi might be a novel therapy for thrombotic disorders.

  20. A proton-shuttle reaction mechanism for histone deacetylase 8 and the catalytic role of metal ions.

    PubMed

    Wu, Ruibo; Wang, Shenglong; Zhou, Nengjie; Cao, Zexing; Zhang, Yingkai

    2010-07-14

    Zinc-dependent histone deacetylase 8 (HDAC8) catalyzes the removal of acetyl moieties from histone tails, and is critically involved in regulating chromatin structure and gene expression. The detailed knowledge of its catalytic process is of high importance since it has been established as a most promising target for the development of new antitumor drugs. By employing Born-Oppenheimer ab initio QM/MM molecular dynamics simulations and umbrella sampling, a state-of-the-art approach to simulate enzyme reactions, we have provided further evidence against the originally proposed general acid-base catalytic pair mechanism for Zinc-dependent histone deacetylases. Instead, our results indicated that HDAC8 employs a proton-shuttle catalytic mechanism, in which a neutral His143 first serves as the general base to accept a proton from the zinc-bound water molecule in the initial rate-determining nucleophilic attack step, and then shuttles it to the amide nitrogen atom to facilitate the cleavage of the amide bond. During the deacetylation process, the Zn(2+) ion changes its coordination mode and plays multiple catalytic roles. For the K(+) ion, which is located about 7 A from the catalytic Zn(2+) ion and conserved in class I and II HDACs, our simulations indicated that its removal would lead to the different transition state structure and a higher free energy reaction barrier for the rate-determining step. It is found that the existence of this conserved K(+) ion would enhance the substrate binding, increase the basicity of His143, strengthen the catalytic role of zinc ion, and improve the transition state stabilization by the enzyme environment.

  1. Synthesis and biological evaluation of histone deacetylase inhibitors that are based on FR235222

    PubMed Central

    Singh, Erinprit K.; Ravula, Suchitra; Pan, Chung-Mao; Pan, Po-Shen; Vasko, Robert C.; Lapera, Stephanie A.; Weerasinghe, Sujith V. W.; Pflum, Mary Kay H.; McAlpine, Shelli R.

    2008-01-01

    We outline the synthesis of six novel derivatives that are based on a recently discovered HDAC inhibitor FR235222. Our work is the first report utilizing a novel binding element, guanidine, as metal coordinators in HDAC inhibitors. Further, we demonstrate that these compounds show cytotoxicity that parallels their ability to inhibit deacetylase activity, and that the most potent compounds maintain an l-Phe at position 1, and a d-Pro at position 4. Both inhibition of HDAC activity and cytotoxicity against the pancreatic cancer cell line BxPC3 are exhibited by these compounds, establishing that a guanidine unit can be utilized successfully to inhibit HDAC activity. PMID:18381239

  2. Recruitment of Cln3 Cyclin to Promoters Controls Cell Cycle Entry via Histone Deacetylase and Other Targets

    PubMed Central

    Cai, Ying; Wijnen, Herman; Futcher, Bruce

    2009-01-01

    In yeast, the G1 cyclin Cln3 promotes cell cycle entry by activating the transcription factor SBF. In mammals, there is a parallel system for cell cycle entry in which cyclin dependent kinase (CDK) activates transcription factor E2F/Dp. Here we show that Cln3 regulates SBF by at least two different pathways, one involving the repressive protein Whi5, and the second involving Stb1. The Rpd3 histone deacetylase complex is also involved. Cln3 binds to SBF at the CLN2 promoter, and removes previously bound Whi5 and histone deacetylase. Adding extra copies of the SBF binding site to the cell delays Start, possibly by titrating Cln3. Since Rpd3 is the yeast ortholog of mammalian HDAC1, there is now a virtually complete analogy between the proteins regulating cell cycle entry in yeast (SBF, Cln3, Whi5 and Stb1, Rpd3) and mammals (E2F, Cyclin D, Rb, HDAC1). The cell may titrate Cln3 molecules against the number of SBF binding sites, and this could be the underlying basis of the size-control mechanism for Start. PMID:19823669

  3. 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

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

    2014-03-07

    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.

  4. Galectin-3, histone deacetylases, and Hedgehog signaling: Possible convergent targets in schistosomiasis-induced liver fibrosis.

    PubMed

    de Oliveira, Felipe Leite; Carneiro, Katia; Brito, José Marques; Cabanel, Mariana; Pereira, Jonathas Xavier; Paiva, Ligia de Almeida; Syn, Wingkin; Henderson, Neil C; El-Cheikh, Marcia Cury

    2017-02-01

    Schistosomiasis affects approximately 240 million people in the world. Schistosoma mansoni eggs in the liver induce periportal fibrosis and hepatic failure driven by monocyte recruitment and macrophage activation, resulting in robust Th2 response. Here, we suggested a possible involvement of Galectin-3 (Gal-3), histone deacetylases (HDACs), and Hedgehog (Hh) signaling with macrophage activation during Th1/Th2 immune responses, fibrogranuloma reaction, and tissue repair during schistosomiasis. Gal-3 is highly expressed by liver macrophages (Kupffer cells) around Schistosoma eggs. HDACs and Hh regulate macrophage polarization and hepatic stellate cell activation during schistosomiasis-associated fibrogenesis. Previously, we demonstrated an abnormal extracellular matrix distribution in the liver that correlated with atypical monocyte-macrophage differentiation in S. mansoni-infected, Gal-3-deficient (Lgals3-/-) mice. New findings explored in this review focus on the chronic phase, when wild-type (Lgals3+/+) and Lgals3-/- mice were analyzed 90 days after cercariae infection. In Lgals3-/- infected mice, there was significant inflammatory infiltration with myeloid cells associated with egg destruction (hematoxylin and eosin staining), phagocytes (specifically Kupffer cells), numerically reduced and diffuse matrix extracellular deposition in fibrotic areas (Gomori trichrome staining), and severe disorganization of collagen fibers surrounding the S. mansoni eggs (reticulin staining). Granuloma-derived stromal cells (GR cells) of Lgals3-/- infected mice expressed lower levels of alpha smooth muscle actin (α-SMA) and eotaxin and higher levels of IL-4 than Lgals3+/+ mice (real-time PCR). The relevant participation of macrophages in these events led us to suggest distinct mechanisms of activation that culminate in defective fibrosis in the liver of Lgals3-/- infected mice. These aspects were discussed in this review, as well as the possible interference between Gal-3, HDACs

  5. Galectin-3, histone deacetylases, and Hedgehog signaling: Possible convergent targets in schistosomiasis-induced liver fibrosis

    PubMed Central

    de Oliveira, Felipe Leite; Carneiro, Katia; Brito, José Marques; Cabanel, Mariana; Pereira, Jonathas Xavier; Paiva, Ligia de Almeida; Syn, Wingkin; Henderson, Neil C.; El-Cheikh, Marcia Cury

    2017-01-01

    Schistosomiasis affects approximately 240 million people in the world. Schistosoma mansoni eggs in the liver induce periportal fibrosis and hepatic failure driven by monocyte recruitment and macrophage activation, resulting in robust Th2 response. Here, we suggested a possible involvement of Galectin-3 (Gal-3), histone deacetylases (HDACs), and Hedgehog (Hh) signaling with macrophage activation during Th1/Th2 immune responses, fibrogranuloma reaction, and tissue repair during schistosomiasis. Gal-3 is highly expressed by liver macrophages (Kupffer cells) around Schistosoma eggs. HDACs and Hh regulate macrophage polarization and hepatic stellate cell activation during schistosomiasis-associated fibrogenesis. Previously, we demonstrated an abnormal extracellular matrix distribution in the liver that correlated with atypical monocyte–macrophage differentiation in S. mansoni-infected, Gal-3-deficient (Lgals3-/-) mice. New findings explored in this review focus on the chronic phase, when wild-type (Lgals3+/+) and Lgals3-/- mice were analyzed 90 days after cercariae infection. In Lgals3-/- infected mice, there was significant inflammatory infiltration with myeloid cells associated with egg destruction (hematoxylin and eosin staining), phagocytes (specifically Kupffer cells), numerically reduced and diffuse matrix extracellular deposition in fibrotic areas (Gomori trichrome staining), and severe disorganization of collagen fibers surrounding the S. mansoni eggs (reticulin staining). Granuloma-derived stromal cells (GR cells) of Lgals3-/- infected mice expressed lower levels of alpha smooth muscle actin (α-SMA) and eotaxin and higher levels of IL-4 than Lgals3+/+ mice (real-time PCR). The relevant participation of macrophages in these events led us to suggest distinct mechanisms of activation that culminate in defective fibrosis in the liver of Lgals3-/- infected mice. These aspects were discussed in this review, as well as the possible interference between Gal-3, HDACs

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

    SciTech Connect

    Lu, Yen-Shen; Chou, Chia-Hung; Tzen, Kai-Yuan; Gao, Ming; Cheng, Ann-Lii; Kulp, Samuel K.; Cheng, Jason Chia-Hsien

    2012-06-01

    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.

  7. Effects of histone deacetylase inhibitor Trichostatin A on epigenetic changes and transcriptional activation of Bdnf promoter 1 by rat hippocampal neurons.

    PubMed

    Tian, Feng; Marini, Ann M; Lipsky, Robert H

    2010-06-01

    Histone acetylation/deacetylation is a central mechanism for regulating transcription through chromatin remodeling. The brain-derived neurotrophic factor gene (Bdnf) is regulated in part through chromatin remodeling. An inhibitor of histone deacetylase (HDAC) activity, Trichostatin A (TSA), has differential effects on two activation dependent regions of the Bdnf gene physically linked to transcription sites for exons 1 and 4. We determined that TSA treatment of cultures of hippocampal neurons produced a stronger response at promoter 1. Transcriptional activation of promoter 1 correlated with increased occupancy of the promoter by acetylated histones (H3AcK9/K14). TSA treatment also produced a time-dependent increase in the level of H3AcK9 and H3AcK14 protein and Hdac1 mRNA levels and HDAC1 protein levels. Taken together, these findings suggest that inhibition of HDAC activity by TSA activates Bdnf transcription and a compensatory change in HDAC1 expression in neurons. This response may reflect a genome-wide change in gene expression.

  8. Glucocorticoid receptor and Histone deacetylase 6 mediate the differential effect of dexamethasone during osteogenesis of mesenchymal stromal cells (MSCs)

    PubMed Central

    Rimando, Marilyn G.; Wu, Hao-Hsiang; Liu, Yu-An; Lee, Chien-Wei; Kuo, Shu-Wen; Lo, Yin-Ping; Tseng, Kuo-Fung; Liu, Yi-Shiuan; Lee, Oscar Kuang-Sheng

    2016-01-01

    Lineage commitment and differentiation of mesenchymal stromal cells (MSCs) into osteoblasts in vitro is enhanced by a potent synthetic form of glucocorticoid (GC), dexamethasone (Dex). Paradoxically, when used chronically in patients, GCs exert negative effects on bone, a phenomenon known as glucocorticoid-induced osteoporosis in clinical practice. The mechanism on how GC differentially affects bone precursor cells to become mature osteoblasts during osteogenesis remains elusive. In this study, the dose and temporal regulation of Dex on MSC differentiation into osteoblasts were investigated. We found that continuous Dex treatment led to a net reduction of the maturation potential of differentiating osteoblasts. This phenomenon correlated with a decrease in glucocorticoid receptor (GR) expression, hastened degradation, and impaired sub cellular localization. Similarly, Histone Deacetylase 6 (HDAC6) expression was found to be regulated by Dex, co-localized with GR and this GR-HDAC6 complex occupied the promoter region of the osteoblast late marker osteocalcin (OCN). Combinatorial inhibition of HDAC6 and GR enhanced OCN expression. Together, the cross-talk between the Dex effector molecule GR and the inhibitory molecule HDAC6 provided mechanistic explanation of the bimodal effect of Dex during osteogenic differentiation of MSCs. These findings may provide new directions of research to combat glucocorticoid-induced osteoporosis. PMID:27901049

  9. Histone deacetylase inhibitors preserve white matter structure and function during ischemia by conserving ATP and reducing excitotoxicity.

    PubMed

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

    2011-03-16

    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 upregulation 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.

  10. Preclinical studies in the mdx mouse model of duchenne muscular dystrophy with the histone deacetylase inhibitor givinostat.

    PubMed

    Consalvi, Silvia; Mozzetta, Chiara; Bettica, Paolo; Germani, Massimiliano; Fiorentini, Francesco; Del Bene, Francesca; Rocchetti, Maurizio; Leoni, Flavio; Monzani, Valmen; Mascagni, Paolo; Puri, Pier Lorenzo; Saccone, Valentina

    2013-05-20

    Previous work has established the existence of dystrophin-nitric oxide (NO) signaling to histone deacetylases (HDACs) that is deregulated in dystrophic muscles. As such, pharmacological interventions that target HDACs (that is, HDAC inhibitors) are of potential therapeutic interest for the treatment of muscular dystrophies. In this study, we explored the effectiveness of long-term treatment with different doses of the HDAC inhibitor givinostat in mdx mice--the mouse model of Duchenne muscular dystrophy (DMD). This study identified an efficacy for recovering functional and histological parameters within a window between 5 and 10 mg/kg/d of givinostat, with evident reduction of the beneficial effects with 1 mg/kg/d dosage. The long-term (3.5 months) exposure of 1.5-month-old mdx mice to optimal concentrations of givinostat promoted the formation of muscles with increased cross-sectional area and reduced fibrotic scars and fatty infiltration, leading to an overall improvement of endurance performance in treadmill tests and increased membrane stability. Interestingly, a reduced inflammatory infiltrate was observed in muscles of mdx mice exposed to 5 and 10 mg/kg/d of givinostat. A parallel pharmacokinetic/pharmacodynamic analysis confirmed the relationship between the effective doses of givinostat and the drug distribution in muscles and blood of treated mice. These findings provide the preclinical basis for an immediate translation of givinostat into clinical studies with DMD patients.

  11. Dual influences of early-life maternal deprivation on histone deacetylase activity and recognition memory in rats.

    PubMed

    Albuquerque Filho, Manoel Osório; de Freitas, Betânia Souza; Garcia, Rebeca Carvalho Lacerda; Crivelaro, Pedro Castilhos de Freitas; Schröder, Nadja; de Lima, Maria Noêmia Martins

    2017-03-06

    Exposure to stress early in life may negatively impact nervous system functioning, including increasing the proneness to learning and memory impairments later in life. Maternal deprivation, a model of early-life stress, hinders memory in adult rats and lessens brain-derived neurotrophic factor (BDNF) levels in the hippocampus in a very heterogeneous way among individuals. The main goal of the present study was to investigate the possible epigenetic modulation underlying recognition memory impairment and reduced BDNF levels in the hippocampus of adult maternally deprived rats. We also evaluated the potential ameliorating properties of the histone deacetylase (HDAC) inhibitor, sodium butyrate, on memory deficits and BDNF changes related to maternal deprivation. Maternally deprived animals were categorized as 'inferior learners' and 'superior learners' according to their performance in object recognition memory task in comparison to controls. Results indicated that HDAC activity was higher in individuals submitted to maternal deprivation with the worst cognitive performance (inferior learners). Acute administration of sodium butyrate increased histone H3 acetylation and BDNF levels, and restored recognition memory in maternally deprived animals with the worst cognitive performance. Moreover, we also showed that there is a positive correlation between BDNF levels and memory performance. Taken together, the results indicated that HDAC inhibitors could be considered as a possible therapeutic agent to improve cognitive performance in inferior learners. Further studies need to be conducted for a better comprehension of the mechanisms related to persistent alterations observed in adult life induced by early stressful circumstances and those leading to resilience.

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

    PubMed Central

    2014-01-01

    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

  13. Histone Deacetylase Inhibition via RGFP966 Releases the Brakes on Sensory Cortical Plasticity and the Specificity of Memory Formation.

    PubMed

    Bieszczad, Kasia M; Bechay, Kiro; Rusche, James R; Jacques, Vincent; Kudugunti, Shashi; Miao, Wenyan; Weinberger, Norman M; McGaugh, James L; Wood, Marcelo A

    2015-09-23

    Research over the past decade indicates a novel role for epigenetic mechanisms in memory formation. Of particular interest is chromatin modification by histone deacetylases (HDACs), which, in general, negatively regulate transcription. HDAC deletion or inhibition facilitates transcription during memory consolidation and enhances long-lasting forms of synaptic plasticity and long-term memory. A key open question remains: How does blocking HDAC activity lead to memory enhancements? To address this question, we tested whether a normal function of HDACs is to gate information processing during memory formation. We used a class I HDAC inhibitor, RGFP966 (C21H19FN4O), to test the role of HDAC inhibition for information processing in an auditory memory model of learning-induced cortical plasticity. HDAC inhibition may act beyond memory enhancement per se to instead regulate information in ways that lead to encoding more vivid sensory details into memory. Indeed, we found that RGFP966 controls memory induction for acoustic details of sound-to-reward learning. Rats treated with RGFP966 while learning to associate sound with reward had stronger memory and additional information encoded into memory for highly specific features of sounds associated with reward. Moreover, behavioral effects occurred with unusually specific plasticity in primary auditory cortex (A1). Class I HDAC inhibition appears to engage A1 plasticity that enables additional acoustic features to become encoded in memory. Thus, epigenetic mechanisms act to regulate sensory cortical plasticity, which offers an information processing mechanism for gating what and how much is encoded to produce exceptionally persistent and vivid memories. Significance statement: Here we provide evidence of an epigenetic mechanism for information processing. The study reveals that a class I HDAC inhibitor (Malvaez et al., 2013; Rumbaugh et al., 2015; RGFP966, chemical formula C21H19FN4O) alters the formation of auditory memory by

  14. Antimalarial activity of phenylthiazolyl-bearing hydroxamate-based histone deacetylase inhibitors.

    PubMed

    Dow, Geoffrey S; Chen, Yufeng; Andrews, Katherine T; Caridha, Diana; Gerena, Lucia; Gettayacamin, Montip; Johnson, Jacob; Li, Qigui; Melendez, Victor; Obaldia, Nicanor; Tran, Thanh N; Kozikowski, Alan P

    2008-10-01

    The antimalarial activity and pharmacology of a series of phenylthiazolyl-bearing hydroxamate-based histone deacetylase inhibitors (HDACIs) was evaluated. In in vitro growth inhibition assays approximately 50 analogs were evaluated against four drug resistant strains of Plasmodium falciparum. The range of 50% inhibitory concentrations (IC(50)s) was 0.0005 to >1 microM. Five analogs exhibited IC(50)s of <3 nM, and three of these exhibited selectivity indices of >600. The most potent compound, WR301801 (YC-2-88) was shown to cause hyperacetylation of P. falciparum histones, which is a marker for HDAC inhibition in eukaryotic cells. The compound also inhibited malarial and mammalian HDAC activity in functional assays at low nanomolar concentrations. WR301801 did not exhibit cures in P. berghei-infected mice at oral doses as high as 640 mg/kg/day for 3 days or in P. falciparum-infected Aotus lemurinus lemurinus monkeys at oral doses of 32 mg/kg/day for 3 days, despite high relative bioavailability. The failure of monotherapy in mice may be due to a short half-life, since the compound was rapidly hydrolyzed to an inactive acid metabolite by loss of its hydroxamate group in vitro (half-life of 11 min in mouse microsomes) and in vivo (half-life in mice of 3.5 h after a single oral dose of 50 mg/kg). However, WR301801 exhibited cures in P. berghei-infected mice when combined at doses of 52 mg/kg/day orally with subcurative doses of chloroquine. Next-generation HDACIs with greater metabolic stability than WR301801 may be useful as antimalarials if combined appropriately with conventional antimalarial drugs.

  15. Histone deacetylase inhibitors as immunomodulators in cancer therapeutics.

    PubMed

    Shen, Li; Orillion, Ashley; Pili, Roberto

    2016-03-01

    HDAC inhibitors (HDACIs) are anticancer agents being developed in preclinical and clinical settings due to their capacity to modulate gene expression involved in cell growth, differentiation and apoptosis, through modification of both chromatin histone and nonhistone proteins. Most HDACIs in clinical development have cytotoxic or cytostatic properties and their direct inhibitory effects on tumor cells are well documented. Numerous studies have revealed that HDACIs have potent immunomodulatory activity in tumor-bearing animals and cancer patients, providing guidance to apply these agents in cancer immunotherapies. Here, we summarize recent reports addressing the effects of HDACIs on tumor cell immunogenicity, and on different components of the host immune system. In addition, we discuss the complexity of the immunomodulatory activity of these agents, which depends on the class specificity of the HDACIs, different experimental settings and the target immune cell populations.

  16. The Class I HDAC Inhibitor RGFP963 Enhances Consolidation of Cued Fear Extinction

    ERIC Educational Resources Information Center

    Bowers, Mallory E.; Xia, Bing; Carreiro, Samantha; Ressler, Kerry J.

    2015-01-01

    Evidence indicates that broad, nonspecific histone deacetylase (HDAC) inhibition enhances learning and memory, however, the contribution of the various HDACs to specific forms of learning is incompletely understood. Here, we show that the Class I HDAC inhibitor, RGFP963, enhances consolidation of cued fear extinction. However, RGFP966, a strong…

  17. Histone Deacetylase Inhibition Activates Transgene Expression from Integration-Defective Lentiviral Vectors in Dividing and Non-Dividing Cells

    PubMed Central

    Pelascini, Laetitia P.L.; Janssen, Josephine M.

    2013-01-01

    Abstract Integration-defective lentiviral vectors (IDLVs) are being increasingly deployed in both basic and preclinical gene transfer settings. Often, however, the IDLV transgene expression profile is muted when compared to that of their integration-proficient counterparts. We hypothesized that the episomal nature of IDLVs turns them into preferential targets for epigenetic silencing involving chromatin-remodeling histone deacetylation. Therefore, vectors carrying an array of cis-acting elements and transcriptional unit components were assembled with the aid of packaging constructs encoding either the wild-type or the class I mutant D116N integrase moieties. The transduction levels and transgene-product yields provided by each vector class were assessed in the presence and absence of the histone deacetylase (HDAC) inhibitors sodium butyrate and trichostatin A. To investigate the role of the target cell replication status, we performed experiments in growth-arrested human mesenchymal stem cells and in post-mitotic syncytial myotubes. We found that IDLVs are acutely affected by HDACs regardless of their genetic makeup or target cell replication rate. Interestingly, the magnitude of IDLV transgene expression rescue due to HDAC inhibition varied in a vector backbone– and cell type–dependent manner. Finally, investigation of histone modifications by chromatin immunoprecipitation followed by quantitative PCR (ChIP-qPCR) revealed a paucity of euchromatin marks distributed along IDLV genomes when compared to those measured on isogenic integration-competent vector templates. These findings support the view that IDLVs constitute preferential targets for epigenetic silencing involving histone deacetylation, which contributes to dampening their full transcriptional potential. Our data provide leads on how to most optimally titrate and deploy these promising episomal gene delivery vehicles. PMID:23140481

  18. Current evidence for histone deacetylase inhibitors in pancreatic cancer

    PubMed Central

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

    2013-01-01

    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

  19. Class IIa Histone Deacetylases and Myocyte Enhancer Factor 2 Proteins Regulate the Mesenchymal-to-Epithelial Transition of Somatic Cell Reprogramming*

    PubMed Central

    Zhuang, Qiang; Qing, Xiaobing; Ying, Yue; Wu, Haitao; Benda, Christina; Lin, Jiao; Huang, Zhijian; Liu, Longqi; Xu, Yan; Bao, Xichen; Qin, Baoming; Pei, Duanqing; Esteban, Miguel A.

    2013-01-01

    Class IIa histone deacetylases (HDACs) and myocyte enhancer factor 2 (MEF2) proteins compose a signaling module that orchestrates lineage specification during embryogenesis. We show here that this module also regulates the generation of mouse induced pluripotent stem cells by defined transcription factors. Class IIa HDACs and MEF2 proteins rise steadily during fibroblast reprogramming to induced pluripotent stem cells. MEF2 proteins tend to block the process by inducing the expression of Tgfβ cytokines, which impairs the necessary phase of mesenchymal-to-epithelial transition (MET). Conversely, class IIa HDACs endeavor to suppress the activity of MEF2 proteins, thus enhancing the MET and colony formation efficiency. Our work highlights an unexpected role for a developmental axis in somatic cell reprogramming and provides new insight into how the MET is regulated in this context. PMID:23467414

  20. Association between histone deacetylases and the loss of cochlear hair cells: Role of the former in noise-induced hearing loss.

    PubMed

    Wen, Li-Ting; Wang, Jie; Wang, Ye; Chen, Fu-Quan

    2015-08-01

    Noise-induced hearing loss (NIHL) is one of the most frequent disabilities in industrialized countries. It has been demonstrated that hair cell loss in the auditory end organ may account for the majority of ear pathological conditions. Previous studies have indicated that histone deacetylases (HDACs) play an important role in neurodegenerative diseases, including hearing impairment, in older persons. Thus, we hypothesized that the inhibition of HDACs would prevent hair cell loss and, consequently, NIHL. In the present study, a CBA/J mouse model of NIHL was established. Following an injection with the HDAC inhibitor, suberoylanilide hydroxamic acid (SAHA), the expression levels of HDAC1, HDAC4 and acetyl-histone H3 (Lys9) (H3-AcK9) were measured. The number of hair cells was quantified and their morphology was observed. The results revealed that 1 h following exposure to 110 dB SPL broadband noise, there was a significant increase in HDAC1 and HDAC4 expression, and a marked decrease in the H3-AcK9 protein levels, as shown by western blot analysis. Pre-treatment with SAHA significantly inhibited these effects. Two weeks following exposure to noise, the mice exhibited significant hearing impairment and an obvious loss in the number of outer hair cells. An abnormal cell morphology with cilia damage was also observed. Pre-treatment with SAHA markedly attenuated these noise-induced effects. Taken together, the findings of our study suggest that HDAC expression is associated with outer hair cell function and plays a significant role in NIHL. Our data indicate that SAHA may be a potential therapeutic agent for the prevention of NIHL.

  1. HDAC1 regulates fear extinction in mice.

    PubMed

    Bahari-Javan, Sanaz; Maddalena, Andrea; Kerimoglu, Cemil; Wittnam, Jessica; Held, Torsten; Bähr, Mathias; Burkhardt, Susanne; Delalle, Ivanna; Kügler, Sebastian; Fischer, Andre; Sananbenesi, Farahnaz

    2012-04-11

    Histone acetylation has been implicated with the pathogenesis of neuropsychiatric disorders and targeting histone deacetylases (HDACs) using HDAC inhibitors was shown to be neuroprotective and to initiate neuroregenerative processes. However, little is known about the role of individual HDAC proteins during the pathogenesis of brain diseases. HDAC1 was found to be upregulated in patients suffering from neuropsychiatric diseases. Here, we show that virus-mediated overexpression of neuronal HDAC1 in the adult mouse hippocampus specifically affects the extinction of contextual fear memories, while other cognitive abilities were unaffected. In subsequent experiments we show that under physiological conditions, hippocampal HDAC1 is required for extinction learning via a mechanism that involves H3K9 deacetylation and subsequent trimethylation of target genes. In conclusion, our data show that hippocampal HDAC1 has a specific role in memory function.

  2. Histone deacetylase inhibitor (HDACI) mechanisms of action: emerging insights.

    PubMed

    Bose, Prithviraj; Dai, Yun; Grant, Steven

    2014-09-01

    Initially regarded as "epigenetic modifiers" acting predominantly through chromatin remodeling via histone acetylation, HDACIs, alternatively referred to as lysine deacetylase or simply deacetylase inhibitors, have since been recognized to exert multiple cytotoxic actions in cancer cells, often through acetylation of non-histone proteins. Some well-recognized mechanisms of HDACI lethality include, in addition to relaxation of DNA and de-repression of gene transcription, interference with chaperone protein function, free radical generation, induction of DNA damage, up-regulation of endogenous inhibitors of cell cycle progression, e.g., p21, and promotion of apoptosis. Intriguingly, this class of agents is relatively selective for transformed cells, at least in pre-clinical studies. In recent years, additional mechanisms of action of these agents have been uncovered. For example, HDACIs interfere with multiple DNA repair processes, as well as disrupt cell cycle checkpoints, critical to the maintenance of genomic integrity in the face of diverse genotoxic insults. Despite their pre-clinical potential, the clinical use of HDACIs remains restricted to certain subsets of T-cell lymphoma. Currently, it appears likely that the ultimate role of these agents will lie in rational combinations, only a few of which have been pursued in the clinic to date. This review focuses on relatively recently identified mechanisms of action of HDACIs, with particular emphasis on those that relate to the DNA damage response (DDR), and discusses synergistic strategies combining HDACIs with several novel targeted agents that disrupt the DDR or antagonize anti-apoptotic proteins that could have implications for the future use of HDACIs in patients with cancer.

  3. Histone deacetylase inhibitor (HDACI) mechanisms of action: emerging insights

    PubMed Central

    Bose, Prithviraj; Dai, Yun; Grant, Steven

    2014-01-01

    Initially regarded as “epigenetic modifiers” acting predominantly through chromatin remodeling via histone acetylation, HDACIs, alternatively referred to as lysine deacetylase or simply deacetylase inhibitors, have since been recognized to exert multiple cytotoxic actions in cancer cells, often through acetylation of non-histone proteins. Some well-recognized mechanisms of HDACI lethality include, in addition to relaxation of DNA and de-repression of gene transcription, interference with chaperone protein function, free radical generation, induction of DNA damage, up-regulation of endogenous inhibitors of cell cycle progression, e.g., p21, and promotion of apoptosis. Intriguingly, this class of agents is relatively selective for transformed cells, at least in pre-clinical studies. In recent years, additional mechanisms of action of these agents have been uncovered. For example, HDACIs interfere with multiple DNA repair processes, as well as disrupt cell cycle checkpoints, critical to the maintenance of genomic integrity in the face of diverse genotoxic insults. Despite their pre-clinical potential, the clinical use of HDACIs remains restricted to certain subsets of T-cell lymphoma. Currently, it appears likely that the ultimate role of these agents will lie in rational combinations, only a few of which have been pursued in the clinic to date. This review focuses on relatively recently identified mechanisms of action of HDACIs, with particular emphasis on those that relate to the DNA damage response (DDR), and discuss synergistic strategies combining HDACIs with several novel targeted agents that disrupt the DDR or antagonize anti-apoptotic proteins that could have implications for the future use of HDACIs in patients with cancer. PMID:24769080

  4. Neuroblastoma stem cells - mechanisms of chemoresistance and histone deacetylase inhibitors.

    PubMed

    Khalil, M A; Hrabeta, J; Cipro, S; Stiborova, M; Vicha, A; Eckschlager, T

    2012-01-01

    Cancer stem cells (CSCs) form a small proportion of tumor cells that have stem cell properties: self-renewal capacity, the ability to develop into different lineages and proliferative potential. The interest in CSCs emerged from their expected role in initiation, progression and recurrence of many tumors. They are generally resistant to conventional chemotherapy and radiotherapy. There are two hypotheses about their origin: The first assumes that CSCs may arise from normal stem cells, and the second supposes that differentiated cells acquire the properties of CSCs. Both hypotheses are not mutually exclusive, as it is possible that CSCs have a diverse origin in different tumors. CD133+ cells (CD133 is marker of CSC in some tumors) isolated from NBL, osteosarcoma and Ewing sarcoma cell lines are resistant to cisplatin, carboplatin, etoposide and doxorubicin than the CD133- ones. Being resistant to chemotherapy, there were many attempts to target CSCs epigenetically including the use of histone deacetylase inhibitors. The diverse influence of valproic acid (histone deacetylase inhibitor) on normal and cancer stem cells was proved in different experiments. We have found an increase percentage of CD133+ NBL cells after their incubation with VPA in a dose that does not induce apoptosis. Further researches on CSCs and clinical application for their detection are necessary: (i) to define the CSC function in carcinogenesis, cancer development and their role in metastasis; (ii) to find a specific marker for CSCs in different tumors; (iii) to explain the role of different pathways that determine their behavior and (iv) to explain mechanisms of chemoresistance of CSCs.

  5. Differential regulation of Bdnf expression in cortical neurons by class-selective histone deacetylase inhibitors.

    PubMed

    Koppel, Indrek; Timmusk, Tõnis

    2013-12-01

    Histone deactylase (HDAC) inhibitors show promise as therapeutics for neurodegenerative and psychiatric diseases. Increased expression of brain-derived neurotrophic factor (BDNF) has been associated with memory-enhancing and neuroprotective properties of these drugs, but the mechanism of BDNF induction is not well understood. Here, we compared the effects of a class I/IIb selective HDAC inhibitor SAHA, a class I selective inhibitor MS-275, a class II selective inhibitor MC1568 and a HDAC6 selective inhibitor tubacin on Bdnf mRNA expression in rat primary neurons. We show that inhibition of class II HDACs resulted in rapid upregulation of Bdnf mRNA levels, whereas class I HDAC inhibition produced a markedly delayed Bdnf induction. In contrast to relatively slow upregulation of Bdnf transcripts, histone acetylation at BDNF promoters I and IV was rapidly induced by SAHA. Bdnf induction by SAHA and MS-275 at 24 h was sensitive to protein synthesis inhibition, suggesting that delayed Bdnf induction by HDAC inhibitors is secondary to changed expression of its regulators. HDAC4 and HDAC5 repressed Bdnf promoter IV activity, supporting the role of class II HDACs in regulation of Bdnf expression. In addition, we show a critical role for the cAMP/Ca2+ response element (CRE) in induction of Bdnf promoter IV by MS-275, MC1568, SAHA and sodium valproate. In contrast, MEF2-binding CaRE1 element was not necessary for promoter IV induction by HDAC inhibition. Finally, we show that similarly to Bdnf, the studied HDAC inhibitors differentially induced expression of neuronal activity-regulated genes c-fos and Arc. Together, our findings implicate class II HDACs in transcriptional regulation of Bdnf and indicate that class II selective HDAC inhibitors may have potential as therapeutics for nervous system disorders.

  6. Histone Deacetylase Inhibitors Globally Enhance H3/H4 Tail Acetylation Without Affecting H3 Lysine 56 Acetylation

    PubMed Central

    Drogaris, Paul; Villeneuve, Valérie; Pomiès, Christelle; Lee, Eun-Hye; Bourdeau, Véronique; Bonneil, Éric; Ferbeyre, Gerardo; Verreault, Alain; Thibault, Pierre

    2012-01-01

    Histone deacetylase inhibitors (HDACi) represent a promising avenue for cancer therapy. We applied mass spectrometry (MS) to determine the impact of clinically relevant HDACi on global levels of histone acetylation. Intact histone profiling revealed that the HDACi SAHA and MS-275 globally increased histone H3 and H4 acetylation in both normal diploid fibroblasts and transformed human cells. Histone H3 lysine 56 acetylation (H3K56ac) recently elicited much interest and controversy due to its potential as a diagnostic and prognostic marker for a broad diversity of cancers. Using quantitative MS, we demonstrate that H3K56ac is much less abundant than previously reported in human cells. Unexpectedly, in contrast to H3/H4 N-terminal tail acetylation, H3K56ac did not increase in response to inhibitors of each class of HDACs. In addition, we demonstrate that antibodies raised against H3K56ac peptides cross-react against H3 N-terminal tail acetylation sites that carry sequence similarity to residues flanking H3K56. PMID:22355734

  7. The Histone Deacetylase Inhibitor BML-210 Influences Gene and Protein Expression in Human Promyelocytic Leukemia NB4 Cells via Epigenetic Reprogramming.

    PubMed

    Borutinskaitė, Veronika; Navakauskienė, Rūta

    2015-08-06

    Today, cancer is understood as an epigenetic as well as genetic disease. The main epigenetic hallmarks of the cancer cell are DNA methylation and histone modifications. Proteins such as histone deacetylases (HDACs) that cause modifications of histones and other proteins can be targets for novel anticancer agents. Recently, interest in compounds that can inhibit HDACs increased, and now there are many HDACs inhibitors (HDACIs) available with different chemical structures, biological and biochemical properties; hopefully some of them will succeed, probably in combination with other agents, in cancer therapies. In our study we focused on the novel HDACI-BML-210. We found that BML-210 (N-phenyl-N'-(2-Aminophenyl)hexamethylenediamide) inhibits the growth of NB4 cells in dose- and time-dependent manner. In this study we also examined how expression and activity of HDACs are affected after leukemia cell treatment with BML-210. Using a mass spectrometry method we identified proteins that changed expression after treatment with BML-210. We prepared RT-PCR analysis of these genes and the results correlated with proteomic data. Based on these and other findings from our group, we suggest that HDACIs, like BML-210, can be promising anticancer agents in promyelocytic leukemia treatment.

  8. Histone Deacetylase Inhibitors in Clinical Studies as Templates for New Anticancer Agents

    PubMed Central

    Mottamal, Madhusoodanan; Zheng, Shilong; Huang, Tien L.; Wang, Guangdi

    2015-01-01

    Histone dacetylases (HDACs) are a group of enzymes that remove acetyl groups from histones and regulate expression of tumor suppressor genes. They are implicated in many human diseases, especially cancer, making them a promising therapeutic target for treatment of the latter by developing a wide variety of inhibitors. HDAC inhibitors interfere with HDAC activity and regulate biological events, such as cell cycle, differentiation and apoptosis in cancer cells. As a result, HDAC inhibitor-based therapies have gained much attention for cancer treatment. To date, the FDA has approved three HDAC inhibitors for cutaneous/peripheral T-cell lymphoma and many more HDAC inhibitors are in different stages of clinical development for the treatment of hematological malignancies as well as solid tumors. In the intensifying efforts to discover new, hopefully more therapeutically efficacious HDAC inhibitors, molecular modeling-based rational drug design has played an important role in identifying potential inhibitors that vary in molecular structures and properties. In this review, we summarize four major structural classes of HDAC inhibitors that are in clinical trials and different computer modeling tools available for their structural modifications as a guide to discover additional HDAC inhibitors with greater therapeutic utility. PMID:25738536

  9. Glucocorticoid receptor and histone deacetylase-2 mediate dexamethasone-induced repression of MUC5AC gene expression.

    PubMed

    Chen, Yajun; Watson, Alan M; Williamson, Chad D; Rahimi, Michael; Liang, Chong; Colberg-Poley, Anamaris M; Rose, Mary C

    2012-11-01

    Airway occlusion in obstructive airway diseases is caused in part by the overproduction of secretory mucin glycoproteins through the up-regulation of mucin (MUC) genes by inflammatory mediators. Some pharmacological agents, including the glucocorticoid dexamethasone (Dex), repress mucin concentrations in lung epithelial cancer cells. Here, we show that Dex reduces the expression of MUC5AC, a major airway mucin gene, in primary differentiated normal human bronchial epithelial (NHBE) cells in a dose-dependent and time-dependent manner, and that the Dex-induced repression is mediated by the glucocorticoid receptor (GR) and two glucocorticoid response elements (GREs) in the MUC5AC promoter. The pre-exposure of cells to RU486, a GR antagonist, and mutations in either the GRE3 or GRE5 cis-sites abolished the Dex-induced repression. Chromatin immunoprecipitation (ChIP) assays showed a rapid temporal recruitment of GR to the GRE3 and GRE5 cis-elements in the MUC5AC promoter in NHBE and in A549 cells. Immunofluorescence showed nuclear colocalization of GR and histone deacetylase-2 (HDAC2) in MUC5AC-expressing NHBE cells. ChIP also showed a rapid temporal recruitment of HDAC2 to the GRE3 and GRE5 cis-elements in the MUC5AC promoter in both cell types. The knockdown of HDAC2 by HDAC2-specific short interfering RNA prevented the Dex-induced repression of MUC5AC in NHBE and A549 cells. These data demonstrate that GR and HDAC2 are recruited to the GRE3 and GRE5 cis-sites in the MUC5AC promoter and mediate the Dex-induced cis repression of MUC5AC gene expression. A better understanding of the mechanisms whereby glucocorticoids repress MUC5AC gene expression may be useful in formulating therapeutic interventions in chronic lung diseases.

  10. Improving potency and metabolic stability by introducing an alkenyl linker to pyridine-based histone deacetylase inhibitors for orally available RUNX3 modulators.

    PubMed

    Song, Doona; Lee, Chulho; Kook, Yoon Jeong; Oh, Soo Jin; Kang, Jong Soon; Kim, Hyun-Jung; Han, Gyoonhee

    2017-01-27

    RUNX3, a tumor suppressor, is suppressed in various cancers by abnormal epigenetic changes. Histone deacetylases (HDACs) can deacetylate the lysine residues of RUNX3, followed by degradation via a ubiquitin-mediated pathway. Inhibition of HDAC leads to functional restoration of the RUNX3 protein by epigenetic expression and RUNX3 protein stabilization. We previously reported a series of HDAC inhibitors that restored RUNX3 function. In the present study, we introduced an alkenyl linker group to pyridine-based HDAC inhibitors to improve their potencies and chemical properties. This alkenyl linker made the compounds more rigid, facilitating a better fit than alkyl moieties to the active site of HDAC proteins. Most compounds in this series exhibited potent RUNX activities, HDAC inhibitory activities, and inhibitory activities towards the growth of human cancer cell lines. Notably, one of these derivatives, (E)-3-(1-cinnamyl-2-oxo-1,2-dihydropyridin-3-yl)-N-hydroxyacrylamide (7k), showed excellent properties in a microsomal stability study, in a xenograft study, and in an in vivo pharmacokinetic evaluation. Modulation of RUNX3 therefore results in highly potent and orally available anticancer chemotherapeutic agents.

  11. cAMP signaling increases histone deacetylase 8 expression by inhibiting JNK-dependent degradation via autophagy and the proteasome system in H1299 lung cancer cells.

    PubMed

    Park, Ji-Yeon; Juhnn, Yong-Sung

    2016-02-05

    This study aimed to investigate the roles of autophagy and the ubiquitin-proteasome system in the degradation of histone deacetylase 8 (HDAC8) and to clarify the mechanism by which cAMP signaling regulates this degradation. cAMP signaling was activated by treating H1299 non-small cell lung cancer cells with isoproterenol or forskolin/3-isobutyl-1-methylxanthine, and HDAC8 expression was assessed by western blot analysis. The inhibition of autophagy and ubiquitin-proteasome-dependent degradation increased HDAC8 expression. cAMP signaling inhibited JNK activation, which decreased the phosphorylation of Bcl-2, thereby reducing autophagy, and the phosphorylation of Itch, thereby reducing ubiquitination. These results suggest that the HDAC8 protein is degraded via autophagy and the ubiquitin-proteasome system and that cAMP signaling increases HDAC8 protein levels by reducing JNK-mediated autophagy and ubiquitin-proteasome-dependent degradation of the HDAC8 protein in H1299 lung cancer cells.

  12. Molecular dynamics of zinc-finger ubiquitin binding domains: a comparative study of histone deacetylase 6 and ubiquitin-specific protease 5.

    PubMed

    Dos Santos Passos, Carolina; Simões-Pires, Claudia A; Carrupt, Pierre-Alain; Nurisso, Alessandra

    2016-12-01

    HDAC6 is a unique cytoplasmic histone deacetylase characterized by two deacetylase domains, and by a zinc-finger ubiquitin binding domain (ZnF-UBP) able to recognize ubiquitin (Ub). The latter has recently been demonstrated to be involved in the progression of neurodegenerative diseases and in mediating infection by the influenza A virus. Nowadays, understanding the dynamic and energetic features of HDAC6 ZnF-UBP-Ub recognition is considered as a crucial step for the conception of HDAC6 potential modulators. In this study, the atomic, solvent-related, and thermodynamic features behind HDAC6 ZnF-UBP-Ub recognition have been analyzed through molecular dynamics simulations. The behavior was then compared to the prototypical ZnF-UBP from ubiquitin-specific protease 5 (USP5) in order to spot relevant differences useful for selective drug design. Principal component analysis highlighted flapping motions of the L2A loop which were lowered down upon Ub binding in both systems. While polar and nonpolar interactions involving Ub G75 and G76 residues were also common features stabilizing both complexes, salt bridges showed a different pattern, more significant in HDAC6 ZnF-UBP-Ub, whose energetic contribution in USP5 ZnF-UBP-Ub was compensated by the presence of a more stable bridging water molecule. Whereas molecular mechanics/Poisson-Boltzmann surface area (MM-PBSA) free energies of binding were comparable for both systems, in agreement with experiments, computational alanine scanning and free energy decomposition data revealed that HDAC6 E1141 and D1178 are potential hotspots for the design of selective HDAC6 modulators.

  13. Histone Deacetylase Activity Represses Gamma Interferon-Inducible HLA-DR Gene Expression following the Establishment of a DNase I-Hypersensitive Chromatin Conformation

    PubMed Central

    Osborne, Aaron; Zhang, Hongquan; Yang, Wen-Ming; Seto, Edward; Blanck, George

    2001-01-01

    Expression of the retinoblastoma tumor suppressor protein (Rb) is required for gamma interferon (IFN-γ)-inducible major histocompatibility complex class II gene expression and transcriptionally productive HLA-DRA promoter occupancy in several human tumor cell lines. Treatment of these Rb-defective tumor cell lines with histone deacetylase (HDAC) inhibitors rescued IFN-γ-inducible HLA-DRA and -DRB mRNA and cell surface protein expression, demonstrating repression of these genes by endogenous cellular HDAC activity. Additionally, Rb-defective, transcriptionally incompetent tumor cells retained the HLA-DRA promoter DNase I-hypersensitive site. Thus, HDAC-mediated repression of the HLA-DRA promoter occurs following the establishment of an apparent nucleosome-free promoter region and before transcriptionally productive occupancy of the promoter by the required transactivators. Repression of HLA-DRA promoter activation by HDAC activity likely involves a YY1 binding element located in the first exon of the HLA-DRA gene. Chromatin immunoprecipitation experiments localized YY1 to the HLA-DRA gene in Rb-defective tumor cells. Additionally, mutation of the YY1 binding site prevented repression of the promoter by HDAC1 and partially prevented activation of the promoter by trichostatin A. Mutation of the octamer element also significantly reduced the ability of HDAC1 to confer repression of inducible HLA-DRA promoter activation. Treatment of Rb-defective tumor cells with HDAC inhibitors greatly reduced the DNA binding activity of Oct-1, a repressor of inducible HLA-DRA promoter activation. These findings represent the first evidence that HDAC activity can repress IFN-γ-inducible HLA class II gene expression and also demonstrate that HDAC activity can contribute to promoter repression following the establishment of a DNase I-hypersensitive chromatin conformation. PMID:11533238

  14. Histone Deacetylase Inhibitors Resensitize EGFR/EGFRvIII-Overexpressing, Erlotinib-Resistant Glioblastoma Cells to Tyrosine Kinase Inhibition.

    PubMed

    Liffers, Katrin; Kolbe, Katarina; Westphal, Manfred; Lamszus, Katrin; Schulte, Alexander

    2016-02-01

    Although the epidermal growth factor receptor (EGFR) is overexpressed and/or amplified in more than 50 % of all glioblastomas (GBM), therapeutic targeting of the EGFR has not yet been successful. Since histone deacetylases (HDAC) have been described as controlling EGFR expression, we combined the EGFR tyrosine kinase inhibitor erlotinib with different HDAC inhibitors (HDACi) and investigated the benefit of combinatorial therapy for glioblastoma cells. Using representative models of EGFR-amplified, erlotinib-sensitive and -resistant GBM with or without EGFRvIII expression, we determined proliferation, migration, and EGFR-dependent signaling in response to erlotinib and HDACi alone or in combination. HDACi significantly inhibited proliferation of erlotinib-resistant GBM cells, partially restored their sensitivity to erlotinib, and also significantly reduced proliferation of all treatment-naïve cell lines tested. In combination with erlotinib, the development of resistance was prevented. The multitargeted EGFR/HDAC-inhibitor CUDC-101 exhibited similar effects. However, inhibition of cell migration was only achieved by targeting EGFR, and HDACi exhibited no additive effect. Mechanistically, we identified an HDACi-dependent decrease of EGFR/EGFRvIII protein expression underlying the anti-proliferative effects of HDACi. In conclusion, HDACi in combination with erlotinib might serve as a treatment option for newly diagnosed, treatment-naïve tumors irrespective of their EGFR status, as well as for treatment-refractory, EGFR-overexpressing GBM.

  15. Synthesis and biological characterization of spiro[2H-(1,3)-benzoxazine-2,4'-piperidine] based histone deacetylase inhibitors.

    PubMed

    Thaler, Florian; Varasi, Mario; Abate, Agnese; Carenzi, Giacomo; Colombo, Andrea; Bigogno, Chiara; Boggio, Roberto; Zuffo, Roberto Dal; Rapetti, Daniela; Resconi, Anna; Regalia, Nickolas; Vultaggio, Stefania; Dondio, Giulio; Gagliardi, Stefania; Minucci, Saverio; Mercurio, Ciro

    2013-06-01

    Histone Deacetylases (HDACs) have become important targets for the treatment of cancer and other diseases. In previous studies we described the development of novel spirocyclic HDAC inhibitors based on the combination of privileged structures with hydroxamic acid moieties as zinc binding group. Herein, we report further explorations, which resulted in the discovery of a new class of spiro[2H-(1,3)-benzoxazine-2,4'-piperidine] derivatives. Several compounds showed good potency of around 100 nM and less in the HDAC inhibition assays, submicromolar IC50 values when tested against tumour cell lines and a remarkable stability in human and mouse microsomes. Two representative examples exhibited a good pharmacokinetic profile with an oral bioavailability equal or higher than 35% and one of them studied in an HCT116 murine xenograft model showing a robust tumour growth inhibition. In addition, the two benzoxazines were found to have a minor affinity for the hERG potassium channel compared to their corresponding ketone analogues.

  16. Screening for inhibitors of histone deacetylase by incorporating a spraying method to micro-arrayed compound screening.

    PubMed

    Sabet, R S; Marcotte, P; Glaser, K; Burns, D J; Warrior, U; Groebe, D R

    2004-03-01

    We have developed a method of spraying assay reagents onto a target gel in the Micro-Arrayed Compound Screening ( micro ARCS) format. After application of target gels to compound sheets, subsequent reagents can be applied by spraying onto the target gel. The spraying method conserves on assay reagents by up to 10-fold, eliminates the need for casting additional agarose gels, and increases the throughput of a screen by 3-fold. To demonstrate the efficacy of applying the spraying method to micro ARCS, we screened over 600,000 compounds for inhibitors of histone deacetylase (HDAC). Commercially available HDAC substrate and reaction developer were sprayed directly onto the gel to initiate the reaction and to amplify the signal, respectively. Picks in the primary screen were retested at a density of 384 compounds per sheet in the micro ARCS format. IC(50) values for active compounds were confirmed in a 96-well plate assay. The screen identified several small molecule inhibitors of the enzyme, including members of several classes of known HDAC inhibitors. The combination of the high-density format of micro ARCS, the efficiency of the spraying method, and a timed sequence of adding assay reagents permitted a screening throughput of 200,000 tests an hour. We present the details of the screening format and the analysis of the hits from the screen.

  17. HDAC and HDAC Inhibitor: From Cancer to Cardiovascular Diseases

    PubMed Central

    Yoon, Somy

    2016-01-01

    Histone deacetylases (HDACs) are epigenetic regulators that regulate the histone tail, chromatin conformation, protein-DNA interaction, and even transcription. HDACs are also post-transcriptional modifiers that regulate the protein acetylation implicated in several pathophysiologic states. HDAC inhibitors have been highlighted as a novel category of anti-cancer drugs. To date, four HDAC inhibitors, Vorinostat, Romidepsin, Panobinostat, and Belinostat, have been approved by the United States Food and Drug Administration. Principally, these HDAC inhibitors are used for hematologic cancers in clinic with less severe side effects. Clinical trials are continuously expanding to address other types of cancer and also nonmalignant diseases. HDAC inhibition also results in beneficial outcomes in various types of neurodegenerative diseases, inflammation disorders, and cardiovascular diseases. In this review, we will briefly discuss 1) the roles of HDACs in the acquisition of a cancer's phenotype and the general outcome of the HDAC inhibitors in cancer, 2) the functional relevance of HDACs in cardiovascular diseases and the possible therapeutic implications of HDAC inhibitors in cardiovascular disease. PMID:26865995

  18. Analysis of Histone Deacetylase-Dependent Effects on Cell Migration Using the Stripe Assay.

    PubMed

    Mertsch, Sonja; Thanos, Solon

    2017-01-01

    For normal embryonic development/morphogenesis, cell migration and homing are well-orchestrated and important events requiring specific cellular mechanisms. In diseases such as cancer deregulated cell migration represents a major problem. Therefore, numerous efforts are under way to understand the molecular mechanisms of tumor cell migration and to generate more efficient tumor therapies. Cell migration assays are one of the most commonly used functional assays. The wound-healing assay or the Boyden chamber assay are variations of these assays. Nearly all of them are two-dimensional assays and the cells can only migrate on one substrate at a time. This is in contrast to the in vivo situation where the cells are faced simultaneously with different surfaces and interact with different cell types. To approach this in vivo situation we used a modified version of the stripe assay designed by Bonhoeffer and colleagues to examine mechanisms of axonal guidance. The design of this assay allows cells to decide between two different substrates offered at the same time. Utilizing alternating neuronal substrates for migration analyses we can partially mimic the complex in vivo situation for brain tumor cells. Here we describe the detailed protocol to perform a modified version of the stripe assay in order to observe substrate-dependent migration effects in vitro, to analyze the effect of Rho-dependent kinases (ROCKS), of histone deacetylases (HDACs) and of other molecules on glioma cells.

  19. Histone deacetylase inhibitors mediate DNA damage repair in ameliorating hemorrhagic cystitis

    PubMed Central

    Haldar, Subhash; Dru, Christopher; Mishra, Rajeev; Tripathi, Manisha; Duong, Frank; Angara, Bryan; Fernandez, Ana; Arditi, Moshe; Bhowmick, Neil A.

    2016-01-01

    Hemorrhagic cystitis is an inflammatory and ulcerative bladder condition associated with systemic chemotherapeutics, like cyclophosphomide. Earlier, we reported reactive oxygen species resulting from cyclophosphamide metabolite, acrolein, causes global methylation followed by silencing of DNA damage repair genes. Ogg1 (8-oxoguanine DNA glycosylase) is one such silenced base excision repair enzyme that can restore DNA integrity. The accumulation of DNA damage results in subsequent inflammation associated with pyroptotic death of bladder smooth muscle cells. We hypothesized that reversing inflammasome-induced imprinting in the bladder smooth muscle could prevent the inflammatory phenotype. Elevated recruitment of Dnmt1 and Dnmt3b to the Ogg1 promoter in acrolein treated bladder muscle cells was validated by the pattern of CpG methylation revealed by bisulfite sequencing. Knockout of Ogg1 in detrusor cells resulted in accumulation of reactive oxygen mediated 8-Oxo-dG and spontaneous pyroptotic signaling. Histone deacetylase (HDAC) inhibitor, suberoylanilide hydroxamic acid (SAHA), restored Ogg1 expression in cells treated with acrolein and mice treated with cyclophosphamide superior to the standard of care, mesna or nicotinamide-induced DNA demethylation. SAHA restored cyclophosphamide-induced bladder pathology to that of untreated control mice. The observed epigenetic imprinting induced by inflammation suggests a new therapeutic target for the treatment of hemorrhagic cystitis. PMID:27995963

  20. RPD3 histone deacetylase and nutrition have distinct but interacting effects on Drosophila longevity.

    PubMed

    Frankel, Stewart; Woods, Jared; Ziafazeli, Tahereh; Rogina, Blanka

    2015-12-01

    Single-gene mutations that extend longevity have revealed regulatory pathways related to aging and longevity. RPD3 is a conserved histone deacetylase (Class I HDAC). Previously we showed that Drosophila rpd3 mutations increase longevity. Here we tested the longevity effects of RPD3 on multiple nutrient levels. Dietary restriction (DR) has additive effects on RPD3-mediated longevity extension, but the effect may be modestly attenuated relative to controls. RPD3 and DR therefore appear to operate by distinct but interacting mechanisms. Since RPD3 regulates transcription, the mRNA levels for two proteins involved in nutrient signaling, 4E-BP and Tor, were examined in rpd3 mutant flies. 4E-BP mRNA was reduced under longevity-increasing conditions. Epistasis between RPD3 and 4E-BP with regard to longevity was then tested. Flies only heterozygous for a mutation in Thor, the 4E-BP gene, have modestly decreased life spans. Flies mutant for both rpd3 and Thor show a superposition of a large RPD3-mediated increase and a small Thor-mediated decrease in longevity at all food levels, consistent with each gene product having distinct effects on life span. However, DR-mediated extension was absent in males carrying both mutations and lessened in females. Our results support the view that multiple discrete but interacting mechanisms regulate longevity.

  1. Improving allogeneic islet transplantation by suppressing Th17 and enhancing Treg with histone deacetylase inhibitors.

    PubMed

    Sugimoto, Koji; Itoh, Takeshi; Takita, Morihito; Shimoda, Masayuki; Chujo, Daisuke; SoRelle, Jeff A; Naziruddin, Bashoo; Levy, Marlon F; Shimada, Mitsuo; Matsumoto, Shinichi

    2014-04-01

    Islet transplantation is a new treatment for achieving insulin independence for patients with severe diabetes. However, major drawbacks of this treatment are the long graft survival, the necessity for immunosuppressive drugs, and the efficacy of transplantation. Donor-specific transfusion (DST) has been shown to reduce rejection after organ transplantation, potentially through enhanced regulatory T-cell (Treg) activity. However, recent findings have shown that activated Treg can be converted into Th17 cells. We focused on histone deacetylase inhibitors (HDACi) because it was reported that inhibition of HDAC activity prevented Treg differentiation into IL17-producing cells. We therefore sought to enhance Treg while suppressing Th17 cells using DST with HDACi to prolong graft survival. To stimulate Treg by DST, we used donor splenocytes. In DST with HDACi group, Foxp3 mRNA expression and Treg population increased in the thymus and spleen, whereas Th17 population decreased. qPCR analysis of lymphocyte mRNA indicated that Foxp3, IL-10, and TGF-b expression increased. However, interleukin 17a, Stat3 (Th17), and IFN-g expression decreased in DST + HDACi group, relative to DST alone. Moreover, DST treated with HDACi prolonged graft survival relative to controls in mice islet transplantation. DST with HDACi may therefore have utility in islet transplantation.

  2. Histone deacetylase inhibitors mediate DNA damage repair in ameliorating hemorrhagic cystitis.

    PubMed

    Haldar, Subhash; Dru, Christopher; Mishra, Rajeev; Tripathi, Manisha; Duong, Frank; Angara, Bryan; Fernandez, Ana; Arditi, Moshe; Bhowmick, Neil A

    2016-12-20

    Hemorrhagic cystitis is an inflammatory and ulcerative bladder condition associated with systemic chemotherapeutics, like cyclophosphomide. Earlier, we reported reactive oxygen species resulting from cyclophosphamide metabolite, acrolein, causes global methylation followed by silencing of DNA damage repair genes. Ogg1 (8-oxoguanine DNA glycosylase) is one such silenced base excision repair enzyme that can restore DNA integrity. The accumulation of DNA damage results in subsequent inflammation associated with pyroptotic death of bladder smooth muscle cells. We hypothesized that reversing inflammasome-induced imprinting in the bladder smooth muscle could prevent the inflammatory phenotype. Elevated recruitment of Dnmt1 and Dnmt3b to the Ogg1 promoter in acrolein treated bladder muscle cells was validated by the pattern of CpG methylation revealed by bisulfite sequencing. Knockout of Ogg1 in detrusor cells resulted in accumulation of reactive oxygen mediated 8-Oxo-dG and spontaneous pyroptotic signaling. Histone deacetylase (HDAC) inhibitor, suberoylanilide hydroxamic acid (SAHA), restored Ogg1 expression in cells treated with acrolein and mice treated with cyclophosphamide superior to the standard of care, mesna or nicotinamide-induced DNA demethylation. SAHA restored cyclophosphamide-induced bladder pathology to that of untreated control mice. The observed epigenetic imprinting induced by inflammation suggests a new therapeutic target for the treatment of hemorrhagic cystitis.

  3. Clinical experience with the novel histone deacetylase inhibitor vorinostat (suberoylanilide hydroxamic acid) in patients with relapsed lymphoma

    PubMed Central

    O'Connor, O A

    2006-01-01

    Preclinical studies indicate that vorinostat (suberoylanilide hydroxamic acid or SAHA) inhibits histone deacetylase (HDAC) activity, increases acetylated histones H2a, H2b, H3, and H4, and thereby induces differentiation and apoptosis in a variety of tumour cell lines, including murine erythroleukaemia, human bladder transitional cell carcinoma, and human breast adenocarcinoma. On the basis of these favourable preclinical findings, vorinostat has been selected as a candidate for clinical development with the potential to treat patients with selected malignances, including Hodgkin's disease and non-Hodgkin's lymphomas. Phase I clinical trials in patients with haematological malignances and solid tumours showed that both intravenous (i.v.) and oral formulations of vorinostat are well tolerated, can inhibit HDAC activity in peripheral blood mononuclear cells and tumour tissue biopsies, and produce objective tumour regression and symptomatic improvement with little clinical toxicity. The dose-limiting toxicities (DLT) of i.v. vorinostat were primarily haematologic and were rapidly reversible within 4–5 days of therapy cessation. In contrast, the DLT for oral vorinostat were primarily non-haematologic (including dehydration, anorexia, diarrhoea, fatigue) and were also rapidly reversible, usually within 3 days. Further research is warranted to optimise the dosing schedule for vorinostat, particularly with respect to dose, timing of administration, and duration of therapy, and to fully delineate the mechanism(s) of antitumour effect of vorinostat in various types of malignances. Several phase II studies are currently ongoing in patients with haematological malignances and solid tumours.

  4. A Systematic Assessment of Radiation Dose Enhancement by 5-Aza-2'-Deoxycytidine and Histone Deacetylase Inhibitors in Head-and-Neck Squamous Cell Carcinoma

    SciTech Connect

    Schutter, Harlinde de; Kimpe, Marlies; Isebaert, Sofie; Nuyts, Sandra

    2009-03-01

    Purpose: Investigations of epigenetic drugs have shown that radiotherapy can be successfully combined with histone deacetylase inhibitors (HDAC-Is) for the treatment of head-and-neck squamous cell carcinoma (HNSCC). Whether the reversal of epigenetic silencing by demethylating agents with or without HDAC-Is can also act as radiosensitizing remains unclear. This study therefore aimed to investigate whether 5-aza-2'-deoxycytidine (DAC) alone or in combination with the HDAC-Is trichostatin A, LBH589, or MGCD0103 could radiosensitize HNSCC tumor cell lines. Methods and Materials: Histone acetylation status and expression of epigenetically silenced genes at the DNA, RNA, and protein levels were assessed as measures of drug effectiveness in six HNSCC cell lines. Based on their colony-forming capacity, colony assays were performed in four of six cell lines to evaluate the radiosensitizing potential of DAC with or without HDAC-Is. Additional assays of cell survival, apoptosis, cell proliferation, and DNA damage were performed. Results: Radiosensitization was observed in two HNSCC cell lines treated with noncytotoxic doses of DAC with or without HDAC-Is before irradiation. The radiosensitizing doses induced histone hyperacetylation and reversal of gene silencing to variable extents and increased radiation-induced cell-cycle arrest. Conclusions: A role for low-dose DAC with or without HDAC-Is as radiosensitizers in HNSCC seems promising and is supportive of future clinical use, especially for combinations of DAC with LBH589 or MGCD0103, although the mechanisms by which they work will require further study.

  5. Carfilzomib interacts synergistically with histone deacetylase inhibitors in mantle cell lymphoma cells in vitro and in vivo.

    PubMed

    Dasmahapatra, Girija; Lembersky, Dmitry; Son, Minkyeong P; Attkisson, Elisa; Dent, Paul; Fisher, Richard I; Friedberg, Jonathan W; Grant, Steven

    2011-09-01

    Interactions between the proteasome inhibitor carfilzomib and the histone deacetylase (HDAC) inhibitors vorinostat and SNDX-275 were examined in mantle cell lymphoma (MCL) cells in vitro and in vivo. Coadministration of very low, marginally toxic carfilzomib concentrations (e.g., 3-4 nmol/L) with minimally lethal vorinostat or SNDX-275 concentrations induced sharp increases in mitochondrial injury and apoptosis in multiple MCL cell lines and primary MCL cells. Enhanced lethality was associated with c-jun-NH,-kinase (JNK) 1/2 activation, increased DNA damage (induction of λH2A.X), and ERK1/2 and AKT1/2 inactivation. Coadministration of carfilzomib and histone deacetylase inhibitors (HDACI) induced a marked increase in reactive oxygen species (ROS) generation and G(2)-M arrest. Significantly, the free radical scavenger tetrakis(4-benzoic acid) porphyrin (TBAP) blocked carfilzomib/HDACI-mediated ROS generation, λH2A.X formation, JNK1/2 activation, and lethality. Genetic (short hairpin RNA) knockdown of JNK1/2 significantly attenuated carfilzomib/HDACI-induced apoptosis, but did not prevent ROS generation or DNA damage. Carfilzomib/HDACI regimens were also active against bortezomib-resistant MCL cells. Finally, carfilzomib/vorinostat coadministration resulted in a pronounced reduction in tumor growth compared with single agent treatment in an MCL xenograft model associated with enhanced apoptosis, λH2A.X formation, and JNK activation. Collectively, these findings suggest that carfilzomib/HDACI regimens warrant attention in MCL.

  6. Effect of high mobility group nonhistone proteins HMG-20 (ubiquitin) and HMG-17 on histone deacetylase activity assayed in vitro.

    PubMed Central

    Mezquita, J; Chiva, M; Vidal, S; Mezquita, C

    1982-01-01

    We have used a method previously described by Reeves and Candido (1) to partially release histone deacetylase from cell nuclei together with putative regulators of the enzyme. Histone deacetylase released from testis cell nuclei and its putative regulators were separated by gel filtration in Sepharose 6B. A peak of low molecular weight contains a heat-stable factor that stimulate histone deacetylase in vitro. Many of the properties of the activator coincide with those of the protein HMG-20 (ubiquitin). Ubiquitin isolated from testis cell nuclei stimulated histone deacetylase in vitro. It has been suggested that HMG-17 partially inhibits histone deacetylase in Fried cell nuclei (2). In our system, HMG-17 shows no inhibitory effect on histone deacetylase activity Images PMID:6280157

  7. Downregulation of Ca2+-activated Cl- channel TMEM16A by the inhibition of histone deacetylase in TMEM16A-expressing cancer cells.

    PubMed

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

    2014-12-01

    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 μM 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.

  8. Downregulation of the Ca(2+)-activated K(+) channel KC a3.1 by histone deacetylase inhibition in human breast cancer cells.

    PubMed

    Ohya, Susumu; Kanatsuka, Saki; Hatano, Noriyuki; Kito, Hiroaki; Matsui, Azusa; Fujimoto, Mayu; Matsuba, Sayo; Niwa, Satomi; Zhan, Peng; Suzuki, Takayoshi; Muraki, Katsuhiko

    2016-04-01

    The intermediate-conductance Ca(2+)-activated K(+) channel KC a3.1 is involved in the promotion of tumor growth and metastasis, and is a potential therapeutic target and biomarker for cancer. Histone deacetylase inhibitors (HDACis) have considerable potential for cancer therapy, however, the effects of HDACis on ion channel expression have not yet been investigated in detail. The results of this study showed a significant decrease in KC a3.1 transcription by HDAC inhibition in the human breast cancer cell line YMB-1, which functionally expresses KCa3.1. A treatment with the clinically available, class I, II, and IV HDAC inhibitor, vorinostat significantly downregulated KC a3.1 transcription in a concentration-dependent manner, and the plasmalemmal expression of the KC a3.1 protein and its functional activity were correspondingly decreased. Pharmacological and siRNA-based HDAC inhibition both revealed the involvement of HDAC2 and HDAC3 in KC a3.1 transcription through the same mechanism. The downregulation of KC a3.1 in YMB-1 was not due to the upregulation of the repressor element-1 silencing transcription factor, REST and the insulin-like growth factor-binding protein 5, IGFBP5. The significant decrease in KC a3.1 transcription by HDAC inhibition was also observed in the KC a3.1-expressing human prostate cancer cell line, PC-3. These results suggest that vorinostat and the selective HDACis for HDAC2 and/or HDAC3 are effective drug candidates for KC a3.1-overexpressing cancers.

  9. Autophagy induction by histone deacetylase inhibitors inhibits HIV type 1.

    PubMed

    Campbell, Grant R; Bruckman, Rachel S; Chu, Yen-Lin; Spector, Stephen A

    2015-02-20

    Histone deacetylase inhibitors (HDACi) are being evaluated in a "shock-and-kill" therapeutic approach to reverse human immunodeficiency virus type-1 (HIV) latency from CD4(+) T cells. Using this approach, HDACi have induced HIV RNA synthesis in latently infected cells from some patients. The hope is that the increase in viral production will lead to killing of the infected cell either by the virus itself or by the patient's immune system, a "sterilizing cure." Although administered within the context of combination antiretroviral therapy, the infection of bystander cells remains a concern. In this study, we investigated the effect of HDACi (belinostat, givinostat, panobinostat, romidepsin, and vorinostat) on the productive infection of macrophages. We demonstrate that the HDACi tested do not alter the initial susceptibility of macrophages to HIV infection. However, we demonstrate that HDACi decrease HIV release from macrophages in a dose-dependent manner (belinostat < givinostat < vorinostat < panobinostat < romidepsin) via degradation of intracellular HIV through the canonical autophagy pathway. This mechanism involves unc-51-like autophagy-activating kinase 1 (ULK1) and the inhibition of the mammalian target of rapamycin and requires the formation of autophagosomes and their maturation into autolysosomes in the absence of increased cell death. These data provide further evidence in support of a role for autophagy in the control of HIV infection and suggest that careful consideration of off-target effects will be essential if HDACi are to be a component of a multipronged approach to eliminate latently infected cells.

  10. Histone deacetylases inhibitors effects on Cryptococcus neoformans major virulence phenotypes.

    PubMed

    Brandão, Fabiana As; Derengowski, Lorena S; Albuquerque, Patrícia; Nicola, André M; Silva-Pereira, Ildinete; Poças-Fonseca, Marcio J

    2015-01-01

    Cryptococcus neoformans undergoes phenotypical changes during host infection in order to promote persistence and survival. Studies have demonstrated that such adaptations require alterations in gene transcription networks by distinct mechanisms. Drugs such as the histone deacetylases inhibitors (HDACi) Sodium Butyrate (NaBut) and Trichostatin A (TSA) can alter the chromatin conformation and have been used to modulate epigenetic states in the treatment of diseases such as cancer. In this work, we have studied the effect of NaBut and TSA on the expression of C. neoformans major virulence phenotypes and on the survival rate of an animal model infected with drugs-treated yeasts. Both drugs affected fungal growth at 37°C more intensely than at 30°C; nonetheless, drugs did not affect cell viability at the concentrations we studied. HDACi also provoked the reduction of the fungal capsule expansion. Phospholipases enzyme activity decreased; mating process and melanin synthesis were also affected by both inhibitors. NaBut led to an increase in the population of cells in G2/M. Treated yeast cells, which were washed in order to remove the drugs from the culture medium prior to the inoculation in the Galleria mellonela infection model, did not cause significant difference at the host survival curve when compared to non-treated cells. Overall, NaBut effects on the impairment of C. neoformans main virulence factors were more intense and stable than the TSA effects.

  11. Attenuation of Choroidal Neovascularization by Histone Deacetylase Inhibitor

    PubMed Central

    Chan, Nymph; He, Shikun; Spee, Christine K.; Ishikawa, Keijiro; Hinton, David R.

    2015-01-01

    Choroidal neovascularization (CNV) is a blinding complication of age-related macular degeneration that manifests as the growth of immature choroidal blood vessels through Bruch’s membrane, where they can leak fluid or hemorrhage under the retina. Here, we demonstrate that the histone deacetylase inhibitor (HDACi) trichostatin A (TSA) can down-regulate the pro-angiogenic hypoxia-inducible factor-1α and vascular endothelial growth factor (VEGF), and up-regulate the anti-angiogenic and neuro-protective pigment epithelium derived factor in human retinal pigment epithelial (RPE) cells. Most strikingly, TSA markedly down-regulates the expression of VEGF receptor-2 in human vascular endothelial cells and, thus, can knock down pro-angiogenic cell signaling. Additionally, TSA suppresses CNV-associated wound healing response and RPE epithelial-mesenchymal transdifferentiation. In the laser-induced model of CNV using C57Bl/6 mice, systemic administration of TSA significantly reduces fluorescein leakage and the size of CNV lesions at post—laser days 7 and 14 as well as the immunohistochemical expression of VEGF, VEGFR2, and smooth muscle actin in CNV lesions at post-laser day 7. This report suggests that TSA, and possibly HDACi’s in general, should be further evaluated for their therapeutic potential for the treatment of CNV. PMID:25807249

  12. Histone deacetylase inhibitors induce autophagy through FOXO1-dependent pathways.

    PubMed

    Zhang, Jianbin; Ng, Shukie; Wang, Jigang; Zhou, Jing; Tan, Shi-Hao; Yang, Naidi; Lin, Qingsong; Xia, Dajing; Shen, Han-Ming

    2015-04-03

    Autophagy is a catabolic process in response to starvation or other stress conditions to sustain cellular homeostasis. At present, histone deacetylase inhibitors (HDACIs) are known to induce autophagy in cells through inhibition of mechanistic target of rapamycin (MTOR) pathway. FOXO1, an important transcription factor regulated by AKT, is also known to play a role in autophagy induction. At present, the role of FOXO1 in the HDACIs-induced autophagy has not been reported. In this study, we first observed that HDACIs increased the expression of FOXO1 at the mRNA and protein level. Second, we found that FOXO1 transcriptional activity was enhanced by HDACIs, as evidenced by increased FOXO1 nuclear accumulation and transcriptional activity. Third, suppression of FOXO1 function by siRNA knockdown or by a chemical inhibitor markedly blocked HDACIs-induced autophagy. Moreover, we found that FOXO1-mediated autophagy is achieved via its transcriptional activation, leading to a dual effect on autophagy induction: (i) enhanced expression of autophagy-related (ATG) genes, and (ii) suppression of MTOR via transcription of the SESN3 (sestrin 3) gene. Finally, we found that inhibition of autophagy markedly enhanced HDACIs-mediated cell death, indicating that autophagy serves as an important cell survival mechanism. Taken together, our studies reveal a novel function of FOXO1 in HDACIs-mediated autophagy in human cancer cells and thus support the development of a novel therapeutic strategy by combining HDACIs and autophagy inhibitors in cancer therapy.

  13. Selective histone deacetylase 6 inhibitors bearing substituted urea linkers inhibit melanoma cell growth.

    PubMed

    Bergman, Joel A; Woan, Karrune; Perez-Villarroel, Patricio; Villagra, Alejandro; Sotomayor, Eduardo M; Kozikowski, Alan P

    2012-11-26

    The incidence of malignant melanoma has dramatically increased in recent years thus requiring the need for improved therapeutic strategies. In our efforts to design selective histone deactylase inhibitors (HDACI), we discovered that the aryl urea 1 is a modestly potent yet nonselective inhibitor. Structure-activity relationship studies revealed that adding substituents to the nitrogen atom of the urea so as to generate compounds bearing a branched linker group results in increased potency and selectivity for HDAC6. Compound 5 g shows low nanomolar inhibitory potency against HDAC6 and a selectivity of ∼600-fold relative to the inhibition of HDAC1. These HDACIs were evaluated for their ability to inhibit the growth of B16 melanoma cells with the most potent and selective HDAC6I being found to decrease tumor cell growth. To the best of our knowledge, this work constitutes the first report of HDAC6-selective inhibitors that possess antiproliferative effects against melanoma cells.

  14. Selective histone deacetylase 6 inhibitors bearing substituted urea linkers inhibit melanoma cell growth

    PubMed Central

    Bergman, Joel A.; Woan, Karrune; Perez-Villarroel, Patricio; Villagra, Alejandro; Sotomayor, Eduardo M.; Kozikowski, Alan P.

    2012-01-01

    The incidence of malignant melanoma has dramatically increased in recent years thus requiring the need for improved therapeutic strategies. In our efforts to design selective histone deactylase inhibitors (HDACI), we discovered that the aryl urea 1 is a modestly potent yet non-selective inhibitor. Structure activity relationship studies revealed that adding substituents to the nitrogen atom of the urea so as to generate compounds bearing a branched linker group results in increased potency and selectivity for HDAC6. Compound 5g shows low nanomolar inhibitory potency against HDAC6 and a selectivity of ~600-fold relative to the inhibition of HDAC1. These HDACIs were evaluated for their ability to inhibit the growth of B16 melanoma cells with the most potent and selective HDAC6I being found to decrease tumor cell growth. To the best of our knowledge, this work constitutes the first report of HDAC6 selective inhibitors that possess antiproliferative effects against melanoma cells. PMID:23009203

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

    SciTech Connect

    Sharma, Bhupesh Sharma, P.M.

    2013-11-15

    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 and brain GSH levels along with increase in serum and 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. - Highlights: • As has induced endothelial dysfunction (Edf) and vascular dementia (VaD). • As has increased oxidative stress, AChE activity and decreased serum NO. • Inhibitors of HDAC and iNOS have attenuated As induced Edf and VaD. • Both the inhibitors have attenuated As induced biochemical changes. • Inhibitor of HDAC and iNOS has shown good potential in

  16. Increased long-term potentiation at medial-perforant path-dentate granule cell synapses induced by selective inhibition of histone deacetylase 3 requires Fragile X mental retardation protein.

    PubMed

    Franklin, Aimee V; Rusche, James R; McMahon, Lori L

    2014-10-01

    Non-selective inhibition of histone deacetylases (HDACs), enzymes that remove acetyl groups from histone core proteins, enhances cognition and NMDAR-dependent long-term potentiation at hippocampal CA3-CA1 synapses. It is not known whether this is a general mechanism by which HDACs modulate plasticity at other hippocampal synapses. Furthermore, it has yet to be tested whether HDAC inhibition can reverse deficits in synaptic plasticity in disease models. Here, we investigated whether inhibition of HDACs, and specifically HDAC3, a class I HDAC isoform known to negatively regulate hippocampus-dependent learning and memory, enhances LTP at medial perforant path-dentate granule cell (MPP-DGC) synapses in wild-type and Fragile X (Fmr1-/y) mice, a model with known LTP deficits at this synapse. The non-selective HDAC inhibitor trichostatin A (TSA) significantly increased the magnitude of LTP at MPP-DGC synapses in wild-type mice, similar to reports at CA3-CA1 synapses. The enhancement of LTP was mimicked by selective HDAC3 inhibition, implicating a role for this isoform in the negative regulation of synaptic plasticity. However, HDAC3 inhibition was completely ineffective in reversing the deficit in LTP at MPP-DGC synapses in slices from Fmr1-/y mice, and in fact, HDAC3 inhibition was unable to induce any improvement whatsoever. These findings indicate that the enhancing effect of HDAC3 inhibition on LTP in wild-type mice requires FMRP, revealing a novel role for FMRP in hippocampal plasticity.

  17. Genetic deletion of the Histone Deacetylase 6 exacerbates selected behavioral deficits in the R6/1 mouse model for Huntington’s disease

    PubMed Central

    Ragot, Alienor; Pietropaolo, Susanna; Vincent, Jean; Delage, Pauline; Zhang, Hongyu; Allinquant, Bernadette; Leinekugel, Xavier; Fischer, André; Cho, Yoon H

    2015-01-01

    Introduction The inhibition of the Histone Deacetylase 6 (HDAC6) increases tubulin acetylation, thus stimulating intracellular vesicle trafficking and brain-derived neurotrophic factor (BDNF) release, that is, cellular processes markedly reduced in Huntington’s disease (HD). Methods We therefore tested that reducing HDAC6 levels by genetic manipulation would attenuate early cognitive and behavioral deficits in R6/1 mice, a mouse model which develops progressive HD-related phenotypes. Results In contrast to our initial hypothesis, the genetic deletion of HDAC6 did not reduce the weight loss or the deficits in cognitive abilities and nest-building behavior shown by R6/1 mice, and even worsened their social impairments, hypolocomotion in the Y-maze, and reduced ultrasonic vocalizations. Conclusions These results weaken the validity of HDAC6 reduction as a possible therapeutic strategy for HD. The data are discussed in terms of additional cellular consequences and anatomical specificity of HDAC6 that could explain these unexpected effects. PMID:26445700

  18. Greater efficacy of atorvastatin versus a non-statin lipid-lowering agent against renal injury: potential role as a histone deacetylase inhibitor

    PubMed Central

    Singh, Ravi Shankar; Chaudhary, Dharmendra Kumar; Mohan, Aradhana; Kumar, Praveen; Chaturvedi, Chandra Prakash; Ecelbarger, Carolyn M.; Godbole, Madan M.; Tiwari, Swasti

    2016-01-01

    Statins, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors have been shown to improve diabetic nephropathy. However, whether they provide protection via Histone deacetylases (HDAC) inhibition is not clear. We conducted a comparative evaluation of Atorvastatin (AT) versus the non-statin cholesterol-lowering drug, Ezetimibe (EZT) on severity of diabetic nephropathy. Streptozotocin-treated male Wistar rats were fed a cholesterol-supplemented diet and gavaged daily with vehicle, AT or EZT. Control rats received normal diet and gavaged vehicle (n = 8–9/group). Diabetes increased blood glucose, urine albumin-to-creatinine ratio (ACR), kidney pathology and HDAC activity, and reduced renal E-cadherin levels. Both AT and EZT reduced circulating cholesterol, attenuated renal pathology, and did not lower blood glucose. However, AT was significantly more effective than EZT at reducing kidney pathology and HDAC activity. Chromatin immunoprecipitation revealed a significantly higher association of acetylated H3 and H4 with the E-cadherin promoter in kidneys from AT-, relative to EZT- or vehicle-treated rats. Moreover, we demonstrated a direct effect of AT, but not EZT, on HDAC-inhibition and, H3 and H4- acetylation in primary glomerular mesangial cells. Overall, both AT and EZT attenuated diabetic nephropathy; however, AT exhibited greater efficacy despite a similar reduction in circulating cholesterol. HDAC-inhibition may underlie greater efficacy of statins in attenuating kidney injury. PMID:27901066

  19. Histone deacetylase 3 inhibition re-establishes synaptic tagging and capture in aging through the activation of nuclear factor kappa B

    PubMed Central

    Sharma, Mahima; Shivarama Shetty, Mahesh; Arumugam, Thiruma Valavan; Sajikumar, Sreedharan

    2015-01-01

    Aging is associated with impaired plasticity and memory. Altered epigenetic mechanisms are implicated in the impairment of memory with advanced aging. Histone deacetylase 3 (HDAC3) is an important negative regulator of memory. However, the role of HDAC3 in aged neural networks is not well established. Late long-term potentiation (late-LTP), a cellular correlate of memory and its associative mechanisms such as synaptic tagging and capture (STC) were studied in the CA1 area of hippocampal slices from 82–84 week old rats. Our findings demonstrate that aging is associated with deficits in the magnitude of LTP and impaired STC. Inhibition of HDAC3 augments the late-LTP and re-establishes STC. The augmentation of late-LTP and restoration of STC is mediated by the activation of nuclear factor kappa B (NFκB) pathway. We provide evidence for the promotion of associative plasticity in aged neural networks by HDAC3 inhibition and hence propose HDAC3 and NFκB as the possible therapeutic targets for treating age -related cognitive decline. PMID:26577291

  20. Histone deacetylases 1 and 2 cooperate in regulating BRCA1, CHK1, and RAD51 expression in acute myeloid leukemia cells

    PubMed Central

    Edwards, Holly; Wang, Guan; Taub, Jeffrey W; Ge, Yubin

    2017-01-01

    Resistance to chemotherapy and a high relapse rate highlight the importance of finding new therapeutic options for the treatment of acute myeloid leukemia (AML). Histone deacetylase (HDAC) inhibitors (HDACIs) are a promising class of drugs for the treatment of AML. HDACIs have limited single-agent clinical activities, but when combined with conventional or investigational drugs they have demonstrated favorable outcomes. Previous studies have shown that decreasing expression of important DNA damage repair proteins enhances standard chemotherapy drugs. In our recent studies, the pan-HDACI panobinostat has been shown to enhance conventional chemotherapy drugs cytarabine and daunorubicin in AML cells by decreasing the expression of BRCA1, CHK1, and RAD51. In this study, we utilized class- and isoform-specific HDACIs and shRNA knockdown of individual HDACs to determine which HDACs are responsible for decreased expression of BRCA1, CHK1, and RAD51 following pan-HDACI treatment in AML cells. We found that inhibition of both HDAC1 and HDAC2 was necessary to decrease the expression of BRCA1, CHK1, and RAD51, enhance cytarabine- or daunorubicin-induced DNA damage and apoptosis, and abrogate cytarabine- or daunorubicin-induced cell cycle checkpoint activation in AML cells. These findings may aid in the development of rationally designed drug combinations for the treatment of AML. PMID:28030834

  1. Romidepsin reduces histone deacetylase activity, induces acetylation of histones, inhibits proliferation, and activates apoptosis in immortalized epithelial endometriotic cells.

    PubMed

    Imesch, Patrick; Fink, Daniel; Fedier, André

    2010-12-01

    Romidepsin inhibited HDAC activity, produced acetylation of the histone proteins, up-regulated p21, and down-regulated cyclins B1 and D1, resulting in proliferation inhibition and apoptosis activation in 11z immortalized epithelial endometriotic cells. Our findings provide evidence that endometriotic cells are sensitive to the epigenetic effects of romidepsin and suggest that endometriosis may be therapeutically targeted by romidepsin.

  2. HDAC6 as a target for neurodegenerative diseases: what makes it different from the other HDACs?

    PubMed Central

    2013-01-01

    Histone deacetylase (HDAC) inhibitors have been demonstrated to be beneficial in animal models of neurodegenerative diseases. Such results were mainly associated with the epigenetic modulation caused by HDACs, especially those from class I, via chromatin deacetylation. However, other mechanisms may contribute to the neuroprotective effect of HDAC inhibitors, since each HDAC may present distinct specific functions within the neurodegenerative cascades. Such an example is HDAC6 for which the role in neurodegeneration has been partially elucidated so far. The strategy to be adopted in promising therapeutics targeting HDAC6 is still controversial. Specific inhibitors exert neuroprotection by increasing the acetylation levels of α-tubulin with subsequent improvement of the axonal transport, which is usually impaired in neurodegenerative disorders. On the other hand, an induction of HDAC6 would theoretically contribute to the degradation of protein aggregates which characterize various neurodegenerative disorders, including Alzheimer’s, Parkinson’s and Hutington’s diseases. This review describes the specific role of HDAC6 compared to the other HDACs in the context of neurodegeneration, by collecting in silico, in vitro and in vivo results regarding the inhibition and/or knockdown of HDAC6 and other HDACs. Moreover, structure, function, subcellular localization, as well as the level of HDAC6 expression within brain regions are reviewed and compared to the other HDAC isoforms. In various neurodegenerative diseases, the mechanisms underlying HDAC6 interaction with other proteins seem to be a promising approach in understanding the modulation of HDAC6 activity. PMID:23356410

  3. Genome-Wide Mapping of Targets of Maize Histone Deacetylase HDA101 Reveals Its Function and Regulatory Mechanism during Seed Development[OPEN

    PubMed Central

    Yang, Hua; Liu, Xinye; Xin, Mingming; Du, Jinkun; Hu, Zhaorong; Peng, HuiRu; Sun, Qixin; Ni, Zhongfu; Yao, Yingyin

    2016-01-01

    Histone deacetylases (HDACs) regulate histone acetylation levels by removing the acetyl group from lysine residues. The maize (Zea mays) HDAC HDA101 influences several aspects of development, including kernel size; however, the molecular mechanism by which HDA101 affects kernel development remains unknown. In this study, we find that HDA101 regulates the expression of transfer cell-specific genes, suggesting that their misregulation may be associated with the defects in differentiation of endosperm transfer cells and smaller kernels observed in hda101 mutants. To investigate HDA101 function during the early stages of seed development, we performed genome-wide mapping of HDA101 binding sites. We observed that, like mammalian HDACs, HDA101 mainly targets highly and intermediately expressed genes. Although loss of HDA101 can induce histone hyperacetylation of its direct targets, this often does not involve variation in transcript levels. A small subset of inactive genes that must be negatively regulated during kernel development is also targeted by HDA101 and its loss leads to hyperacetylation and increased expression of these inactive genes. Finally, we report that HDA101 interacts with members of different chromatin remodeling complexes, such as NFC103/MSI1 and SNL1/SIN3-like protein corepressors. Taken together, our results reveal a complex genetic network regulated by HDA101 during seed development and provide insight into the different mechanisms of HDA101-mediated regulation of transcriptionally active and inactive genes. PMID:26908760

  4. Inhibition and Mechanism of HDAC8 Revisited

    PubMed Central

    2015-01-01

    Histone deacetylases (HDACs) have found intense interest as drug targets for a variety of diseases, but there is disagreement about basic aspects of the inhibition and mechanism of HDACs. QM/MM calculations of HDAC8 including a large QM region provide a model that is consistent with the available crystal structures and structure–activity relationships of different HDAC inhibitors. The calculations support a spontaneous proton transfer from a hydroxamic acid to an active site histidine upon binding to the zinc. The role of the H142/D176 catalytic dyad as the general base of the reaction is elucidated. The reasons for the disagreements between previous proposals are discussed. The results provide detailed insights into the unique mechanism of HDACs, including the role of the two catalytic dyads and function of the potassium near the active site. They also have important implications for the design of novel inhibitors for a number of HDACs such as the class IIa HDACs. PMID:25060069

  5. Resetting the epigenetic histone code in the MRL-lpr/lpr mouse model of lupus by histone deacetylase inhibition.

    PubMed

    Garcia, Benjamin A; Busby, Scott A; Shabanowitz, Jeffrey; Hunt, Donald F; Mishra, Nilamadhab

    2005-01-01

    The baseline level of gene expression varies between healthy controls and systemic lupus erythematosus (SLE) patients, and among SLE patients themselves. These variations may explain the different clinical manifestations and severity of disease observed in SLE. Epigenetic mechanisms, which involve DNA and histone modifications, are predictably associated with distinct transcriptional states. To understand the interplay between various histone modifications, including acetylation and methylation, and lupus disease, we performed differential expression histone modification analysis in splenocytes from the MRL-lpr/lpr mouse model of lupus. Using stable isotope labeling in combination with mass spectrometry, we found global site-specific hypermethylation (except H3 K4 methylation) and hypoacetylation in histone H3 and H4 MRL-lpr/lpr mice compared to control MRL/MPJ mice. Moreover, we have identified novel histone modifications such as H3 K18 methylation, H4 K31 methylation, and H4 K31 acetylation that are differentially expressed in MRL-lpr/lpr mice compared to controls. Finally, in vivo administration of the histone deacetylase inhibitor trichostatin A (TSA) corrected the site-specific hypoacetylation states on H3 and H4 in MRL-lpr/lpr mice with improvement of disease phenotype. Thus, this study is the first to establish the association between aberrant histone codes and pathogenesis of autoimmune disease SLE. These aberrant post-translational histone modifications can therefore be reset with histone deacetylase inhibition in vivo.

  6. Brainstem brain-derived neurotrophic factor signaling is required for histone deacetylase inhibitor-induced pain relief.

    PubMed

    Tao, Wenjuan; Chen, Quan; Wang, Lu; Zhou, Wenjie; Wang, Yunping; Zhang, Zhi

    2015-06-01

    Our previous study demonstrated that persistent pain can epigenetically suppress the transcription of Gad2 [encoding glutamic acid decarboxylase 65 (GAD65)] and consequently impair the inhibitory function of GABAergic synapses in central pain-modulating neurons. This contributes to the development of persistent pain sensitization. Histone deacetylase (HDAC) inhibitors increased GAD65 activity considerably, restored GABA synaptic function, and rendered sensitized pain behavior less pronounced. However, the molecular mechanisms by which HDAC regulates GABAergic transmission through GAD65 under pain conditions are unknown. This work showed that HDAC inhibitor-induced increases in colocalization of GAD65 and synaptic protein synapsin I on the presynaptic axon terminals of the nucleus raphe magnus (NRM) were blocked by a TrkB receptor antagonist K252a [(9S,10R,12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid methyl ester], indicating that BDNF-TrkB signaling may be required in GAD65 modulation of GABA synaptic function. At the brain-derived neurotrophic factor (BDNF) promoter, HDAC inhibitors induced significant increases in H3 hyperacetylation, consistent with the increase in BDNF mRNA and total proteins. Although exogenous BDNF facilitated GABA miniature inhibitory postsynaptic currents and GAD65 accumulation in NRM neuronal synapses in normal rats, it failed to do so in animals subjected to persistent inflammation. In addition, blockade of the TrkB receptor with K252a has no effect on miniature inhibitory postsynaptic currents and synaptic GAD65 accumulation under normal conditions. In addition, the analgesic effects of HDAC inhibitors on behavior were blocked by NRM infusion of K252a. These findings suggest that BDNF-TrkB signaling is required for drugs that reverse the epigenetic effects of chronic pain at the gene level, such as HDAC inhibitors.

  7. Epigenetic modulation of the protein kinase A RIIα (PRKAR2A) gene by histone deacetylases 1 and 2 in human smooth muscle cells.

    PubMed

    Karolczak-Bayatti, Magdalena; Loughney, Andrew D; Robson, Stephen C; Europe-Finner, G Nicholas

    2011-01-01

    Recently we reported that the expression of the protein kinase A (PKA) regulatory subunit RIIα is dynamically regulated in human smooth muscle cells of the uterus. We showed that expression levels of mRNA/protein were substantially increased during pregnancy and decreased upon labour, changes that were mirrored by particulate type II PKA activity. This implied an important role for RIIα in maintaining uterine quiescence during pregnancy. Consequently the purpose of the present study was to identify potential mechanisms by which expression of the RIIα gene was regulated in this tissue. We indicate here that the three SpI-III (GC) binding domains within the proximal promoter region of the human RIIα gene may play important roles in modulating expression of the gene in human myometrial cells. We show that all three GC binding domains are involved in binding Sp1, Sp3, histone deacetylase (HDACs) 1/2 and RbAp48 transcriptional complexes. The functional significance of these binding domains was further analysed employing in vitro luciferase reporter assays with full-length/truncated RIIα promoter constructs. Importantly we show that treatment of primary human myometrial cell cultures with the general class I/II HDAC inhibitor trichostatin A results in an increase in mRNA/protein levels. Moreover the increase in mRNA levels appeared to be preceded by an increase in aH3, PolIIa, Sp3 and HDAC 2 binding to the three SpI-III (GC) binding sites within the RIIα promoter. These results enable us to provide a model whereby RIIα expression is epigenetically regulated in human myometrial smooth muscle cells by histone deacetylase(s) activity within the GC-rich proximal promoter region of the gene.

  8. Histone deacetylase inhibitor pracinostat in doublet therapy: a unique strategy to improve therapeutic efficacy and to tackle herculean cancer chemoresistance.

    PubMed

    Ganai, Shabir Ahmad

    2016-09-01

    Context Histone deacetylase inhibitors (HDACi) have shown promising results in neurodegeneration and cancer. Hydroxamate HDACi, including vorinostat, have shown encouraging results in haematological malignancies, but the poor pharmacokinetic of these inhibitors leads to insufficient tumour concentration limiting their application against solid malignancies. Objective This article deals with novel HDAC inhibitor pracinostat (SB939) and delineates its therapeutic role in solid and haematological malignancies. The article provides rigorous details about the underlying molecular mechanisms modulated by pracinostat to exert cytotoxic effect. The article further highlights the doublet therapy that may be used to tackle monotonous cancer chemoresistance. Methods Both old and the latest literature on pracinostat was retrieved from diverse sources, such as PubMed, Science Direct, Springer Link, general Google search using both pracinostat and SB939 keywords in various ways: after thorough evaluation the topic which can fulfil the current gap was chosen. Results Pracinostat shows potent anticancer activity against both solid and haematological malignancies compared to the FDA-approved drug vorinostat. This marvellous inhibitor has better physicochemical, pharmaceutical and pharmacokinetic properties than the defined inhibitor vorinostat. Pracinostat has  >100-fold more affinity towards HDACs compared to other zinc-dependent metalloenzymes and shows maximum efficacy when used in doublet therapy. Conclusion Pracinostat shows potent anticancer activity even against therapeutically challenging cancers when used in doublet therapy. However, the triplet combination studies of the defined inhibitor that may prove even more beneficial are still undone, emphasizing the desperate need of further research in the defined gap.

  9. Combined inhibition of BET family proteins and histone deacetylases as a potential epigenetics-based therapy for pancreatic ductal adenocarcinoma

    PubMed Central

    Mazur, Pawel K; Herner, Alexander; Mello, Stephano S; Wirth, Matthias; Hausmann, Simone; Sánchez-Rivera, Francisco J; Lofgren, Shane M; Kuschma, Timo; Hahn, Stephan A; Vangala, Deepak; Trajkovic-Arsic, Marija; Gupta, Aayush; Heid, Irina; Noël, Peter B; Braren, Rickmer; Erkan, Mert; Kleeff, Jörg; Sipos, Bence; Sayles, Leanne C; Heikenwalder, Mathias; Heßmann, Elisabeth; Ellenrieder, Volker; Esposito, Irene; Jacks, Tyler; Bradner, James E; Khatri, Purvesh; Sweet-Cordero, E Alejandro; Attardi, Laura D; Schmid, Roland M; Schneider, Guenter; Sage, Julien; Siveke, Jens T

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers and shows resistance to any therapeutic strategy used. Here we tested small-molecule inhibitors targeting chromatin regulators as possible therapeutic agents in PDAC. We show that JQ1, an inhibitor of the bromodomain and extraterminal (BET) family of proteins, suppresses PDAC development in mice by inhibiting both MYC activity and inflammatory signals. The histone deacetylase (HDAC) inhibitor SAHA synergizes with JQ1 to augment cell death and more potently suppress advanced PDAC. Finally, using a CRISPR-Cas9–based method for gene editing directly in the mouse adult pancreas, we show that de-repression of p57 (also known as KIP2 or CDKN1C) upon combined BET and HDAC inhibition is required for the induction of combination therapy–induced cell death in PDAC. SAHA is approved for human use, and molecules similar to JQ1 are being tested in clinical trials. Thus, these studies identify a promising epigenetic-based therapeutic strategy that may be rapidly implemented in fatal human tumors. PMID:26390243

  10. Intercellular transfer of P-glycoprotein in human blood-brain barrier endothelial cells is increased by histone deacetylase inhibitors

    PubMed Central

    Noack, Andreas; Noack, Sandra; Buettner, Manuela; Naim, Hassan Y.; Löscher, Wolfgang

    2016-01-01

    The blood–brain barrier (BBB) controls the entry of compounds into the brain, thereby regulating brain homeostasis. Efflux transporters such as P-glycoprotein (Pgp) significantly contribute to BBB function. Multiple signaling pathways modulate the expression and activity of Pgp in response to xenobiotics and disease. A non-genetic way of intercellular transfer of Pgp occurs in cancer cells, but whether this also occurs in non-cancer cells such as endothelial cells that form the BBB is not known. A human brain endothelial cell line (hCMEC/D3) was used to study whether cell-to-cell Pgp transfer occurs during co-culturing with Pgp-EGFP expressing hCMEC/D3 cells. The Pgp-EGFP fusion protein was transferred from donor to recipient cells by cell-to-cell contact and Pgp-EGFP enriched vesicles, which were exocytosed by donor cells and endocytosed by adherent recipient cells. Flow cytometry experiments with the Pgp substrate eFLUXX-ID Gold demonstrated that the transferred Pgp is functional in the recipient cells. Exposure of the donor cells with inhibitors of histone deacetylases (HDACs) resulted in an enhanced intercellular Pgp transfer. Non-genetic transfer of a resistance phenotype and its regulation by HDACs is a novel mechanism of altering BBB functionality. This mechanism may have important implications for understanding drug-induced alterations in Pgp expression and activity. PMID:27375084

  11. The histone deacetylase inhibitor trichostatin A reduces lysosomal pH and enhances cisplatin-induced apoptosis.

    PubMed

    Eriksson, I; Joosten, M; Roberg, K; Ollinger, K

    2013-01-01

    High activity of histone deacetylases (HDACs) has been documented in several types of cancer and may be associated with survival advantage. In a head and neck squamous cell carcinoma cell line, cisplatin-induced apoptosis was augmented by pretreatment with the HDAC inhibitor trichostatin A. Apoptosis was accompanied by lysosomal membrane permeabilization (LMP), as shown by immunoblotting of the lysosomal marker protease cathepsin B in extracted cytosol and by immunofluorescence. Moreover, LAMP-2 (lysosomal associated membrane protein-2) was translocated from lysosomal membranes and found in a digitonin extractable fraction together with cytosolic proteins and pretreatment with trichostatin A potentiated the release. Overall, protein level of LAMP-2 was decreased during cell death and, interestingly, inhibition of cysteine cathepsins, by the pan-cysteine cathepsin inhibitor zFA-FMK, prevented loss of LAMP-2. The importance of LAMP-2 for lysosomal membrane stability, was confirmed by showing that LAMP-2 knockout MEFs (mouse embryonic fibroblasts) were more sensitive to cisplatin as compared to the corresponding wildtype cells. Trichostatin A reduced lysosomal pH from 4.46 to 4.25 and cell death was prevented when lysosomal pH was increased by NH(4)Cl, or when inhibiting the activity of lysosomal proteases. We conclude that trichostatin A enhances cisplatin induced cell death by decreasing lysosomal pH, which augments cathepsin activity resulting in reduced LAMP-2 level, and might promote LMP.

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

    PubMed

    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

    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.

  13. HDAC1 and HDAC2 collectively regulate intestinal stem cell homeostasis.

    PubMed

    Zimberlin, Cheryl D; Lancini, Cesare; Sno, Rachel; Rosekrans, Sanne L; McLean, Chelsea M; Vlaming, Hanneke; van den Brink, Gijs R; Bots, Michael; Medema, Jan Paul; Dannenberg, Jan-Hermen

    2015-05-01

    Histone deacetylases (HDACs) are posttranslational modifiers that deacetylate proteins. Despite their crucial role in numerous biological processes, the use of broad-range HDAC inhibitors (HDACi), has shown clinical efficacy. However, undesired side effects highlight the necessity to better understand the biology of different HDACs and target the relevant HDACs. Using a novel mouse model, in which HDAC1 and HDAC2 can be simultaneously deleted in the intestine of adult mice, we show that the simultaneous deletion of HDAC1 and HDAC2 leads to a rapid loss of intestinal homeostasis. Importantly, this deletion cannot be sustained, and 8 days after initial ablation, stem cells that have escaped HDAC1 or HDAC2 deletion swiftly repopulate the intestinal lining. In vitro ablation of HDAC1 and HDAC2 using intestinal organoid cultures resulted in a down-regulation of multiple intestinal stem cell markers and functional loss of clonogenic capacity. Importantly, treatment of wild-type organoids with class I-specific HDACi MS-275 also induced a similar loss of stemness, providing a possible rationale for the gastrointestinal side effects often observed in HDACi-treated patients. In conclusion, these data show that HDAC1 and HDAC2 have a redundant function and are essential to maintain intestinal homeostasis.

  14. Histone deacetylase 6–mediated selective autophagy regulates COPD-associated cilia dysfunction

    PubMed Central

    Lam, Hilaire C.; Cloonan, Suzanne M.; Bhashyam, Abhiram R.; Haspel, Jeffery A.; Singh, Anju; Sathirapongsasuti, J. Fah; Cervo, Morgan; Yao, Hongwei; Chung, Anna L.; Mizumura, Kenji; An, Chang Hyeok; Shan, Bin; Franks, Jonathan M.; Haley, Kathleen J.; Owen, Caroline A.; Tesfaigzi, Yohannes; Washko, George R.; Quackenbush, John; Silverman, Edwin K.; Rahman, Irfan; Kim, Hong Pyo; Mahmood, Ashfaq; Biswal, Shyam S.; Ryter, Stefan W.; Choi, Augustine M.K.

    2013-01-01

    Chronic obstructive pulmonary disease (COPD) involves aberrant airway inflammatory responses to cigarette smoke (CS) that are associated with epithelial cell dysfunction, cilia shortening, and mucociliary clearance disruption. Exposure to CS reduced cilia length and induced autophagy in vivo and in differentiated mouse tracheal epithelial cells (MTECs). Autophagy-impaired (Becn1+/– or Map1lc3B–/–) mice and MTECs resisted CS-induced cilia shortening. Furthermore, CS increased the autophagic turnover of ciliary proteins, indicating that autophagy may regulate cilia homeostasis. We identified cytosolic deacetylase HDAC6 as a critical regulator of autophagy-mediated cilia shortening during CS exposure. Mice bearing an X chromosome deletion of Hdac6 (Hdac6–/Y) and MTECs from these mice had reduced autophagy and were protected from CS-induced cilia shortening. Autophagy-impaired Becn1–/–, Map1lc3B–/–, and Hdac6–/Y mice or mice injected with an HDAC6 inhibitor were protected from CS-induced mucociliary clearance (MCC) disruption. MCC was preserved in mice given the chemical chaperone 4-phenylbutyric acid, but was disrupted in mice lacking the transcription factor NRF2, suggesting that oxidative stress and altered proteostasis contribute to the disruption of MCC. Analysis of human COPD specimens revealed epigenetic deregulation of HDAC6 by hypomethylation and increased protein expression in the airways. We conclude that an autophagy-dependent pathway regulates cilia length during CS exposure and has potential as a therapeutic target for COPD. PMID:24200693

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

    PubMed

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

    2012-05-01

    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.

  16. Inhibition of class IIb histone deacetylase significantly improves cloning efficiency in mice.

    PubMed

    Ono, Tetsuo; Li, Chong; Mizutani, Eiji; Terashita, Yukari; Yamagata, Kazuo; Wakayama, Teruhiko

    2010-12-01

    Since the first mouse clone was produced by somatic cell nuclear transfer, the success rate of cloning in mice has been extremely low. Some histone deacetylase inhibitors, such as trichostatin A and scriptaid, have improved the full-term development of mouse clones significantly, but the mechanisms allowing for this are unclear. Here, we found that two other specific inhibitors, suberoylanilide hydroxamic acid and oxamflatin, could also reduce the rate of apoptosis in blastocysts, improve the full-term development of cloned mice, and increase establishment of nuclear transfer-generated embryonic stem cell lines significantly without leading to obvious abnormalities. However, another inhibitor, valproic acid, could not improve cloning efficiency. Suberoylanilide hydroxamic acid, oxamflatin, trichostatin A, and scriptaid are inhibitors for classes I and IIa/b histone deacetylase, whereas valproic acid is an inhibitor for classes I and IIa, suggesting that inhibiting class IIb histone deacetylase is an important step for reprogramming mouse cloning efficiency.

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

    PubMed

    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

    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.

  18. Mechanisms of ceramide-mediated repression of the human telomerase reverse transcriptase promoter via deacetylation of Sp3 by histone deacetylase 1.

    PubMed

    Wooten-Blanks, Leslie G; Song, Pengfei; Senkal, Can E; Ogretmen, Besim

    2007-10-01

    In this study, distinct roles of de novo-generated endogenous ceramides and mechanisms by which deacetylated Sp3 regulates the hTERT promoter activity in response to ceramide signaling were explored. The generation of C18-ceramide via the expression of ceramide synthase 1 (CerS1), and not C16-ceramide by CerS5 or CerS6 expression, resulted in repression of the hTERT promoter via deacetylation of Sp3 by histone deacetylase 1 (HDAC1) in A549 human lung adenocarcinoma cells. Then roles and mechanisms of action of ceramide-mediated deacetylation of Sp3 in inhibiting the hTERT promoter were determined using constitutively deacetylated or acetylated Sp3 mutants at lysine (K) 551. Expression of the deacetylated Sp3 mutant resulted in repression, whereas its acetylated mutant induced basal hTERT promoter activity in Drosophila S2 cells, which do not express any endogenous Sp3, and in A549 cells. Remarkably, chromatin immunoprecipitation data revealed that acetylated Sp3 mutant (K551Q-Sp3) did not bind whereas deacetylated Sp3 (K551R-Sp3) mutant bound strongly to the promoter DNA, resulting in the recruitment of histone deacetylase 1 (HDAC1) and inhibition of the association of RNA polymerase II with the promoter. Mechanistically, increased generation of C18-ceramide by hCerS1 expression, but not by its catalytically inactive mutant, mediated the association and recruitment of the deacetylated Sp3/HDAC1 complex to the hTERT promoter DNA, resulting in the local histone H3 deacetylation and repression of the promoter.

  19. Generation of Tissue-Specific Mouse Models to Analyze HDAC Functions.

    PubMed

    Hagelkruys, Astrid; Moser, Mirjam A; Seiser, Christian

    2017-01-01

    Histone deacetylases (HDACs) play crucial roles during mammalian development and for cellular homeostasis. In addition, these enzymes are promising targets for small molecule inhibitors in the treatment of cancer and neurological diseases. Conditional HDAC knock-out mice are excellent tools for defining the functions of individual HDACs in vivo and for identifying the molecular targets of HDAC inhibitors in disease. Here, we describe the generation of tissue-specific HDAC knock-out mice and delineate a strategy for the generation of conditional HDAC knock-in mice.

  20. Histone deacetylase inhibitors: a potential epigenetic treatment for Duchenne muscular dystrophy.

    PubMed

    Consalvi, Silvia; Saccone, Valentina; Mozzetta, Chiara

    2014-01-01

    Duchenne muscular dystrophy (DMD) is a life-threatening genetic disease that currently has no available cure. A number of pharmacological strategies that aim to target events downstream of the genetic defect are currently under clinical investigation, and some of these are outlined in this report. In particular, we focus on the ability of histone deacetylase inhibitors to promote muscle regeneration and prevent the fibro-adipogenic degeneration of dystrophic mice. We describe the rationale behind the translation of histone deacetylase inhibitors into a clinical approach, which inspired the first clinical trial with an epigenetic drug as a potential therapeutic option for DMD patients.

  1. Histone Deacetylase Inhibition Rescues Gene Knockout Levels Achieved with Integrase-Defective Lentiviral Vectors Encoding Zinc-Finger Nucleases

    PubMed Central

    Pelascini, Laetitia P.L.; Maggio, Ignazio; Liu, Jin; Holkers, Maarten; Cathomen, Toni

    2013-01-01

    Abstract Zinc-finger nucleases (ZFNs) work as dimers to induce double-stranded DNA breaks (DSBs) at predefined chromosomal positions. In doing so, they constitute powerful triggers to edit and to interrogate the function of genomic sequences in higher eukaryotes. A preferred route to introduce ZFNs into somatic cells relies on their cotransduction with two integrase-defective lentiviral vectors (IDLVs) each encoding a monomer of a functional heterodimeric pair. The episomal nature of IDLVs diminishes the risk of genotoxicity and ensures the strict transient expression profile necessary to minimize deleterious effects associated with long-term ZFN activity. However, by deploying IDLVs and conventional lentiviral vectors encoding HPRT1- or eGFP-specific ZFNs, we report that DSB formation at target alleles is limited after IDLV-mediated ZFN transfer. This IDLV-specific underperformance stems, to a great extent, from the activity of chromatin-remodeling histone deacetylases (HDACs). Importantly, the prototypic and U.S. Food and Drug Administration–approved inhibitors of metal-dependent HDACs, trichostatin A and vorinostat, respectively, did not hinder illegitimate recombination-mediated repair of targeted chromosomal DSBs. This allowed rescuing IDLV-mediated site-directed mutagenesis to levels approaching those achieved by using their isogenic chromosomally integrating counterparts. Hence, HDAC inhibition constitutes an efficacious expedient to incorporate in genome-editing strategies based on transient IDLV-mediated ZFN expression. Finally, we compared two of the most commonly used readout systems to measure targeted gene knockout activities based on restriction and mismatch-sensitive endonucleases. These experiments indicate that these enzymatic assays display a similar performance. PMID:24059449

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

    PubMed

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

    2013-01-01

    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'.

  3. Histone Deacetylase 3 Inhibition Overcomes BIM Deletion Polymorphism-Mediated Osimertinib Resistance in EGFR-Mutant Lung Cancer.

    PubMed

    Tanimoto, Azusa; Takeuchi, Shinji; Arai, Sachiko; Fukuda, Koji; Yamada, Tadaaki; Roca, Xavier; Ong, S Tiong; Yano, Seiji

    2016-12-16

    Purpose: The BIM deletion polymorphism is associated with apoptosis resistance to EGFR tyrosine kinase inhibitors (EGFR-TKI), such as gefitinib and erlotinib, in non-small cell lung cancer (NSCLC) harboring EGFR mutations. Here, we investigated whether the BIM deletion polymorphism contributes to resistance against osimertinib, a third-generation EGFR-TKI. In addition, we determined the efficacy of a histone deacetylase (HDAC) inhibitor, vorinostat, against this form of resistance and elucidated the underlying mechanism.Experimental Design: We used EGFR-mutated NSCLC cell lines, which were either heterozygous or homozygous for the BIM deletion polymorphism, to evaluate the effect of osimertinib in vitro and in vivo Protein expression was examined by Western blotting. Alternative splicing of BIM mRNA was analyzed by RT-PCR.Results:EGFR-mutated NSCLC cell lines with the BIM deletion polymorphism exhibited apoptosis resistance to osimertinib in a polymorphism dosage-dependent manner, and this resistance was overcome by combined use with vorinostat. Experiments with homozygous BIM deletion-positive cells revealed that vorinostat affected the alternative splicing of BIM mRNA in the deletion allele, increased the expression of active BIM protein, and thereby induced apoptosis in osimertinib-treated cells. These effects were mediated predominantly by HDAC3 inhibition. In xenograft models, combined use of vorinostat with osimertinib could regress tumors in EGFR-mutated NSCLC cells homozygous for the BIM deletion polymorphism. Moreover, this combination could induce apoptosis even when tumor cells acquired EGFR-T790M mutations.Conclusions: These findings indicate the importance of developing HDAC3-selective inhibitors, and their combined use with osimertinib, for treating EGFR-mutated lung cancers carrying the BIM deletion polymorphism. Clin Cancer Res; 1-11. ©2016 AACR.

  4. Histone deacetylase is required for the activation of Wnt/β-catenin signaling crucial for heart valve formation in zebrafish embryos.

    PubMed

    Kim, Young-Seop; Kim, Myoung-Jin; Koo, Tae-Hee; Kim, Jun-Dae; Koun, Soonil; Ham, Hyung Jin; Lee, You Mie; Rhee, Myungchull; Yeo, Sang-Yeob; Huh, Tae-Lin

    2012-06-22

    During vertebrate heart valve formation, Wnt/β-catenin signaling induces BMP signals in atrioventricular canal (AVC) myocardial cells and underlying AVC endocardial cells then undergo endothelial-mesenchymal transdifferentiation (EMT) by receiving this BMP signals. Histone deacetylases (HDACs) have been implicated in numerous developmental processes by regulating gene expression. However, their specific roles in controlling heart valve development are largely unexplored. To investigate the role of HDACs in vertebrate heart valve formation, we treated zebrafish embryos with trichostatin A (TSA), an inhibitor of class I and II HDACs, from 36 to 48 h post-fertilization (hpf) during which heart looping and valve formation occur. Following TSA treatment, abnormal linear heart tube development was observed. In these embryos, expression of AVC myocardial bmp4 and AVC endocardial notch1b genes was markedly reduced with subsequent failure of EMT in the AVC endocardial cells. However, LiCl-mediated activation of Wnt/β-catenin signaling was able to rescue defective heart tube formation, bmp4 and notch1b expression, and EMT in the AVC region. Taken together, our results demonstrated that HDAC activity plays a pivotal role in vertebrate heart tube formation by activating Wnt/β-catenin signaling which induces bmp4 expression in AVC myocardial cells.

  5. Histone deacetylase class-I inhibition promotes epithelial gene expression in pancreatic cancer cells in a BRD4- and MYC-dependent manner.

    PubMed

    Mishra, Vivek Kumar; Wegwitz, Florian; Kosinsky, Robyn Laura; Sen, Madhobi; Baumgartner, Roland; Wulff, Tanja; Siveke, Jens T; Schildhaus, Hans-Ulrich; Najafova, Zeynab; Kari, Vijayalakshmi; Kohlhof, Hella; Hessmann, Elisabeth; Johnsen, Steven A

    2017-03-27

    Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with a particularly dismal prognosis. Histone deacetylases (HDAC) are epigenetic modulators whose activity is frequently deregulated in various cancers including PDAC. In particular, class-I HDACs (HDAC 1, 2, 3 and 8) have been shown to play an important role in PDAC. In this study, we investigated the effects of the class I-specific HDAC inhibitor (HDACi) 4SC-202 in multiple PDAC cell lines in promoting tumor cell differentiation. We show that 4SC-202 negatively affects TGFβ signaling and inhibits TGFβ-induced epithelial-to-mesenchymal transition (EMT). Moreover, 4SC-202 markedly induced p21 (CDKN1A) expression and significantly attenuated cell proliferation. Mechanistically, genome-wide studies revealed that 4SC-202-induced genes were enriched for Bromodomain-containing Protein-4 (BRD4) and MYC occupancy. BRD4, a well-characterized acetyllysine reader, has been shown to play a major role in regulating transcription of selected subsets of genes. Importantly, BRD4 and MYC are essential for the expression of a subgroup of genes induced by class-I HDACi. Taken together, our study uncovers a previously unknown role of BRD4 and MYC in eliciting the HDACi-mediated induction of a subset of genes and provides molecular insight into the mechanisms of HDACi action in PDAC.

  6. Long-Term Culture of Porcine Induced Pluripotent Stem-Like Cells Under Feeder-Free Conditions in the Presence of Histone Deacetylase Inhibitors.

    PubMed

    Petkov, Stoyan; Glage, Silke; Nowak-Imialek, Monika; Niemann, Heiner

    2016-03-01

    The reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) is a complex process that involves significant epigenetic alterations in the reprogrammed cells. Epigenetic modifiers such as histone deacetylase (HDAC) inhibitors have been shown to increase the efficiency of derivation of iPSCs in humans and mice. In this study, we used three HDAC inhibitors, valproic acid, sodium butyrate, and suberoylanilide hydroxamic acid, together with ascorbic acid, for derivation and long-term feeder-free culture of porcine iPS-like cells. In the absence of exogenous growth factors and/or small molecules, these inhibitors were able to maintain the expression of key pluripotency markers, including genes known to be specific for naive pluripotent state in mouse stem cells, for over 60 passages under feeder-free conditions. Surprisingly, the cells became dependent on HDAC inhibitors for the maintenance of proliferation. Moreover, despite showing successful integration into blastocysts upon injection, the cells were unable to undergo normal differentiation in vitro and in vivo in the form of teratomas. Our results suggest that HDAC inhibitors maintain pluripotency gene expression of porcine iPSC-like cells in long-term culture, but prevent lineage specification, requiring further optimization of culture conditions for porcine iPSC derivation.

  7. NL-103, a novel dual-targeted inhibitor of histone deacetylases and hedgehog pathway, effectively overcomes vismodegib resistance conferred by Smo mutations.

    PubMed

    Zhao, Jie; Quan, Haitian; Xie, Chengying; Lou, Liguang

    2014-06-01

    Misregulation of hedgehog (Hh) signaling has been implicated in the pathogenesis of basal cell carcinoma (BCC) and medulloblastoma. Vismodegib, an orally bioavailable Hh signal pathway inhibitor targeting Smo, has been approved for the treatment of advanced BCC. However, acquired drug resistance to vismodegib induced by point mutation in Smo is emerging as a major problem to vismodegib treatment. In this study, we designed and synthesized a novel chimeric compound NL-103, which comprises structural elements of Hh pathway inhibitor vismodegib, and histone deacetylase (HDAC) inhibitor vorinostat. NL-103 simultaneously and significantly inhibited both HDACs and Hh pathway. Importantly, NL-103, as well as vorinostat, effectively overcame vismodegib resistance induced by Smoothened point mutations. Moreover, NL-103 and vorinostat, but not vismodegib, significantly downregulated the expression of Gli2 which plays an important role in Hh pathway. These results indicate that HDAC inhibitory activity is essential for NL-103 to overcome vismodegib resistance and that dual inhibition of HDAC and Hh signaling pathway may be a rational strategy for overcoming vismodegib resistance. Our findings suggest that NL-103 may be a promising compound for clinical development as a more effective Hh pathway inhibitor.

  8. Utilization of Boron Compounds for the Modification of Suberoyl Anilide Hydroxamic Acid as Inhibitor of Histone Deacetylase Class II Homo sapiens

    PubMed Central

    Bakri, Ridla; Parikesit, Arli Aditya; Satriyanto, Cipta Prio; Kerami, Djati; Tambunan, Usman Sumo Friend

    2014-01-01

    Histone deacetylase (HDAC) has a critical function in regulating gene expression. The inhibition of HDAC has developed as an interesting anticancer research area that targets biological processes such as cell cycle, apoptosis, and cell differentiation. In this study, an HDAC inhibitor that is available commercially, suberoyl anilide hydroxamic acid (SAHA), has been modified to improve its efficacy and reduce the side effects of the compound. Hydrophobic cap and zinc-binding group of these compounds were substituted with boron-based compounds, whereas the linker region was substituted with p-aminobenzoic acid. The molecular docking analysis resulted in 8 ligands with ΔGbinding value more negative than the standards, SAHA and trichostatin A (TSA). That ligands were analyzed based on the nature of QSAR, pharmacological properties, and ADME-Tox. It is conducted to obtain a potent inhibitor of HDAC class II Homo sapiens. The screening process result gave one best ligand, Nova2 (513246-99-6), which was then further studied by molecular dynamics simulations. PMID:25214833

  9. Selective class I histone deacetylase inhibitors suppress persistent spontaneous nociception and thermal hypersensitivity in a rat model of bee venom-induced inflammatory pain.

    PubMed

    Yang, Fan; Yang, Yan; Wang, Yan; Yang, Fei; Li, Chun-Li; Wang, Xiao-Liang; Li, Zhen; Chen, Jun

    2015-10-25

    To confirm whether class I histone deacetylase inhibitors (HDACIs) are effective in relief of peripheral inflammatory pain, the effects of two selective inhibitors, MS-275 and MGCD0103, were studied in rats inflamed by subcutaneous (s.c.) injection of bee venom (BV). The BV test is characterized by displaying both persistent spontaneous nociception (PSN) and primary hypersensitivity. Intrathecal (i.t.) pre-treatment of either MS-275 or MGCD0103 with a single dose of 60 nmol/20 μL resulted in profound suppression of both PSN and primary thermal hypersensitivity but without significant influence upon the primary mechanical hypersensitivity and mirror-image thermal hypersensitivity. Moreover, the up-regulation of both HDAC1 and HDAC2 induced by s.c. BV injection was completely suppressed by i.t. pre-treatment of MS-275. The present results provide with another new line of evidence showing involvement of epigenetic regulation of chromatin structure by HDAC1/2-mediated histone hypoacetylation in the BV-induced PSN and thermal hypersensitivity and demonstrate the beneficial effects of class I HDACIs in prevention of peripheral inflammatory pain from occurring.

  10. Histone deacetylase activators: N-acetylthioureas serve as highly potent and isozyme selective activators for human histone deacetylase-8 on a fluorescent substrate.

    PubMed

    Singh, Raushan K; Mandal, Tanmay; Balsubramanian, Narayanaganesh; Viaene, Tajae; Leedahl, Travis; Sule, Nitesh; Cook, Gregory; Srivastava, D K

    2011-10-01

    We report, for the first time, that certain N-acetylthiourea derivatives serve as highly potent and isozyme selective activators for the recombinant form of human histone deacetylase-8 in the assay system containing Fluor-de-Lys as a fluorescent substrate. The experimental data reveals that such activating feature is manifested via decrease in the K(m) value of the enzyme's substrate and increase in the catalytic turnover rate of the enzyme.

  11. Effects of apicidin, a histone deacetylase inhibitor, on the regulation of apoptosis in H-ras-transformed breast epithelial cells.

    PubMed

    Park, Hyeyoung; Im, Ji Young; Kim, Jeonga; Choi, Wahn Soo; Kim, Hyung Sik

    2008-03-01

    The cellular susceptibility of cancer cells to histone deacetylase (HDAC) inhibitors is increased by the etopic expression of oncogenic Ras. However, the ability of HDAC inhibitors to regulate the apoptotic pathway in human breast cancer cells is still not completely understood. In this study, the anti-proliferative effects of apicidin were compared in H-ras-transformed human breast epithelial (MCF10A-ras) and non-transformed epithelial (MCF10A) cells. MCF10A-ras cells showed a significantly higher growth rate than MCF10A cells. Apicidin significantly increased the levels of acetylated histone H3 and H4 in both cell lines. Western blot analysis and flow cytometry were used to determine if the anti-proliferative effects of apicidin in MCF10A and MCF10A-ras cells could be mediated by modulating the cell cycle. Apicidin attenuated the expression of cyclin E and CDK2 in MCF10A cells, decreased cyclin D1 and cyclin E levels in MCF10A-ras cells, and increased the levels of CDK inhibitors, p21WAF1/Cip1 and p27Kip1, in both cell lines. Notably, the levels of hyperphosphorylation of the Rb protein levels were lower in the MCF10A-ras cells after apicidin treatment. Studies on the regulation of apoptosis showed that apicidin induces the up-regulation of p53 and the downstream activation of ERK in MCF10A-ras cells. The up-regulation of p53 promoted Bax expression leading to activation of caspases-9 and -6, and eventually to apoptosis in MCF10A-ras cells. In addition, apicidin significantly increased the levels of ERK1/2 phosphorylation in MCF10A-ras cells. Therefore, the apicidin-mediated ERK pathway appears to play an important role in modulating the pro-apoptotic pathway in MCF10A-ras cells.

  12. The Histone Deacetylase Inhibitor Vaproic Acid Induces Cell Growth Arrest in Hepatocellular Carcinoma Cells via Suppressing Notch Signaling

    PubMed Central

    Sun, Guangchun; Mackey, Lily V.; Coy, David H.; Yu, Cui-Yun; Sun, Lichun

    2015-01-01

    Hepatocellular carcinoma (HCC) is a type of malignant cancer. Notch signaling is aberrantly expressed in HCC tissues with more evidence showing that this signaling plays a critical role in HCCs. In the present study, we investigate the effects of the anti-convulsant drug valproic acid (VPA) in HCC cells and its involvement in modulating Notch signaling. We found that VPA, acting as a histone deacetylase (HDAC) inhibitor, induced a decrease in HDAC4 and an increase in acetylated histone 4 (AcH4) and suppressed HCC cell growth. VPA also induced down-regulation of Notch signaling via suppressing the expression of Notch1 and its target gene HES1, with an increase of tumor suppressor p21 and p63. Furthermore, Notch1 activation via overexpressing Notch1 active form ICN1 induced HCC cell proliferation and anti-apoptosis, indicating Notch signaling played an oncogenic role in HCC cells. Meanwhile, VPA could reverse Notch1-induced increase of cell proliferation. Interestingly, VPA was also observed to stimulate the expression of G protein-coupled somatostatin receptor type 2 (SSTR2) that has been used in receptor-targeting therapies. This discovery supports a combination therapy of VPA with the SSTR2-targeting agents. Our in vitro assay did show that the combination of VPA and the peptide-drug conjugate camptothecin-somatostatin (CPT-SST) displayed more potent anti-proliferative effects on HCC cells than did each alone. VPA may be a potential drug candidate in the development of anti-HCC drugs via targeting Notch signaling, especially in combination with receptor-targeting cytotoxic agents. PMID:26366213

  13. Defining the role of histone deacetylases in the inhibition of mammary carcinogenesis by dietary energy restriction (DER): effects of suberoylanilide hydroxamic acid (SAHA) and DER in a rat model.

    PubMed

    Zhu, Zongjian; Jiang, Weiqin; McGinley, John N; Thompson, Henry J

    2013-04-01

    Dietary energy restriction (DER) inhibits experimentally induced mammary cancer, an effect accompanied by elevated levels of silent information regulator 2 (SIRT1), a class III histone deacetylase (HDAC). However, the effect of DER on targets of other classes of HDACs has not been reported, a highly relevant issue given evidence that HDAC induction favors the development of cancer and tumor growth. Experiments were carried out to determine whether suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor with broad activity, would affect the anti-cancer activity of DER. Female Sprague Dawley rats (n = 30/group) were injected with 1-methyl-1-nitrosourea (50 mg/kg) at 21 days of age and 7 days thereafter were randomized to groups fed: (i) control diet (AIN-93G), (ii) 0.1% SAHA (w/w), (iii) 40% DER, or (iv) 0.1% SAHA + 40% DER. An additional group was fed 0.1% SAHA + 40%DER for 5 weeks and released to control diet for 3 weeks. DER significantly reduced mammary cancer incidence, multiplicity, and cancer burden and prolonged cancer latency (P < 0.01). Cancer inhibition was maintained in SAHA + DER, despite evidence that histone (H2A(Lys9), H2B(Lys5), and H4(Lys5/8/12/16), but not H3(Lys9); P < 0.001) and non-histone protein deacetylation (p53(Lys373) and p53(Lys382); P < 0.001) induced by DER was reversed by SAHA. This indicates that the inhibition of DER of cancer is not dependent on HDAC induction. After releasing rats from DER + SAHA, cancer multiplicity remained lower than control (P < 0.05), consistent with apoptosis-mediated cell deletion. These findings support further investigation of the hypothesis that HDAC induction by DER blunts its anti-carcinogenic impact.

  14. HDAC1 and HDAC2 independently predict mortality in hepatocellular carcinoma by a competing risk regression model in a Southeast Asian population

    PubMed Central

    LER, SER YENG; LEUNG, CAROL HO WING; KHIN, LAY WAI; LU, GUO-DONG; SALTO-TELLEZ, MANUEL; HARTMAN, MIKAEL; IAU, PHILIP TSAU CHOONG; YAP, CELESTIAL T.; HOOI, SHING CHUAN

    2015-01-01

    Histone deacetylases (HDACs) are enzymes involved in transcriptional repression. We aimed to examine the significance of HDAC1 and HDAC2 gene expression in the prediction of recurrence and survival in 156 patients with hepatocellular carcinoma (HCC) among a South East Asian population who underwent curative surgical resection in Singapore. We found that HDAC1 and HDAC2 were upregulated in the majority of HCC tissues. The presence of HDAC1 in tumor tissues was correlated with poor tumor differentiation. Notably, HDAC1 expression in adjacent non-tumor hepatic tissues was correlated with the presence of satellite nodules and multiple lesions, suggesting that HDAC1 upregulation within the field of HCC may contribute to tumor spread. Using competing risk regression analysis, we found that increased cancer-specific mortality was significantly associated with HDAC2 expression. Mortality was also increased with high HDAC1 expression. In the liver cancer cell lines, HEP3B, HEPG2, PLC5, and a colorectal cancer cell line, HCT116, the combined knockdown of HDAC1 and HDAC2 increased cell death and reduced cell proliferation as well as colony formation. In contrast, knockdown of either HDAC1 or HDAC2 alone had minimal effects on cell death and proliferation. Taken together, our study suggests that both HDAC1 and HDAC2 exert pro-survival effects in HCC cells, and the combination of isoform-specific HDAC inhibitors against both HDACs may be effective in targeting HCC to reduce mortality. PMID:26352599

  15. Maternal Exposure of Rats to Isoflurane during Late Pregnancy Impairs Spatial Learning and Memory in the Offspring by Up-Regulating the Expression of Histone Deacetylase 2

    PubMed Central

    Hu, Yan; Zhao, Weilu; Zuo, Zhiyi; Yu, Qi; Liu, Zhiyi; Lin, Jiamei; Feng, Yunlin; Li, Binda; Wu, Liuqin; Xu, Lin

    2016-01-01

    Increasing evidence indicates that most general anesthetics can harm developing neurons and induce cognitive dysfunction in a dose- and time-dependent manner. Histone deacetylase 2 (HDAC2) has been implicated in synaptic plasticity and learning and memory. Our previous results showed that maternal exposure to general anesthetics during late pregnancy impaired the offspring’s learning and memory, but the role of HDAC2 in it is not known yet. In the present study, pregnant rats were exposed to 1.5% isoflurane in 100% oxygen for 2, 4 or 8 hours or to 100% oxygen only for 8 hours on gestation day 18 (E18). The offspring born to each rat were randomly subdivided into 2 subgroups. Thirty days after birth, the Morris water maze (MWM) was used to assess learning and memory in the offspring. Two hours before each MWM trial, an HDAC inhibitor (SAHA) was given to the offspring in one subgroup, whereas a control solvent was given to those in the other subgroup. The results showed that maternal exposure to isoflurane impaired learning and memory of the offspring, impaired the structure of the hippocampus, increased HDAC2 mRNA and downregulated cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) mRNA, N-methyl-D-aspartate receptor 2 subunit B (NR2B) mRNA and NR2B protein in the hippocampus. These changes were proportional to the duration of the maternal exposure to isoflurane and were reversed by SAHA. These results suggest that exposure to isoflurane during late pregnancy can damage the learning and memory of the offspring rats via the HDAC2-CREB -NR2B pathway. This effect can be reversed by HDAC2 inhibition. PMID:27536989

  16. 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

    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

    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

  17. Synthesis and biochemical analysis of 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoro-N-hydroxy-octanediamides as inhibitors of human histone deacetylases.

    PubMed

    Henkes, Leonhard M; Haus, Patricia; Jäger, Felix; Ludwig, Joachim; Meyer-Almes, Franz-Josef

    2012-01-15

    Inhibition of human histone deacetylases (HDACs) has emerged as a novel concept in the chemotherapeutic treatment of cancer. Two chemical entities, SAHA (ZOLINZA, Merck) and romidepsin (Istodax, Celgene) have been recently approved by the FDA as first-in-class drugs against cutaneous T-cell lymphoma. Clinical use of these drugs revealed several side effects including gastro-intestinal symptoms, fatigue, thrombocytopenia, thrombosis. Romidepsin is associated with an yet unresolved cardiotoxicity issue. A general hypothesis for the diminishment of unwanted adverse effects and an improved therapeutical window suggests the development of more isotype selective inhibitors. In this study the first time HDAC inhibitors with perfluorinated spacers between the zinc chelating moiety and the aromatic capping group were synthesized and tested against representatives of HDAC classes I, IIa and IIb. Competitive binding assays and a combined approach by using blind docking and molecular dynamics support binding of the perfluorinated analogs of SAHA to the active site of the HDAC-like amidohydrolase from Bordetella/Alcaligenes and presumably also to human HDACs. In contrast to the alkyl spacer of SAHA and derivatives, the perfluorinated alkyl spacer seems to contribute to or facilitate the induction of selectivity for class II, particularly class IIa, HDACs even though the overall potency of the perfluorinated SAHA analogs in this study against human HDACs remained still rather moderate in the micromolar range.

  18. Histone tail modifications and noncanonical functions of histones: perspectives in cancer epigenetics.

    PubMed

    Hadnagy, Annamaria; Beaulieu, Raymond; Balicki, Danuta

    2008-04-01

    Over the past few years, the histone deacetylase (HDAC) inhibitors have occupied an important place in the effort to develop novel, but less toxic, anticancer therapy. HDAC inhibitors block HDACs, which are the enzymes responsible for histone deacetylation, and therefore they modulate gene expression. The cellular effects of HDAC inhibitors include growth arrest and the induction of differentiation. Early successes in cancer therapeutics obtained using these drugs alone or in combination with other anticancer drugs emphasize the important place of posttranslational modifications of histones in cancer therapy. Histone tail modifications along with DNA methylation are the most studied epigenetic events related to cancer progression. Moreover, extranuclear functions of histones have also been described. Because HDAC inhibitors block HDACs and thereby increase histone acetylation, we propose a model wherein exogenous acetylated histones or other related acetylated proteins that are introduced into the nucleus become HDAC substrates and thereby compete with endogenous histones for HDACs. This competition may lead to the increased acetylation of the endogenous histones, as in the case of HDAC inhibitor therapy. Moreover, other mechanisms of action, such as binding to chromatin and modulating gene expression, are also possible for exogenously introduced histones.

  19. The histone deacetylase inhibitor belinostat (PXD101) suppresses bladder cancer cell growth in vitro and in vivo

    PubMed Central

    Buckley, Michael T; Yoon, Joanne; Yee, Herman; Chiriboga, Luis; Liebes, Leonard; Ara, Gulshan; Qian, Xiaozhong; Bajorin, Dean F; Sun, Tung-Tien; Wu, Xue-Ru; Osman, Iman

    2007-01-01

    Background Treatment options for patients with recurrent superficial bladder cancer are limited, necessitating aggressive exploration of new treatment strategies that effectively prevent recurrence and progression to invasive disease. We assessed the effects of belinostat (previously PXD101), a novel histone deacetylase inhibitor, on a panel of human bladder cancer cell lines representing superficial and invasive disease, and on a transgenic mouse model of superficial bladder cancer. Methods Growth inhibition and cell cycle distribution effect of belinostat on 5637, T24, J82, and RT4 urothelial lines were assessed. Ha-ras transgenic mice with established superficial bladder cancer were randomized to receive either belinostat or vehicle alone, and assessed for bladder weight, hematuria, gene expression profiling, and immunohistochemistry (IHC). Results Belinostat had a significant linear dose-dependent growth inhibition on all cell lines (IC50 range of 1.0–10.0 μM). The 5637 cell line, which was derived from a superficial papillary tumor, was the most sensitive to treatment. Belinostat (100 mg/kg, intraperitoneal, 5 days each week for 3 weeks) treated mice had less bladder weight (p < 0.05), and no hematuria compared with 6/10 control mice that developed at least one episode. IHC of bladder tumors showed less cell proliferation and a higher expression of p21WAF1 in the belinostat-treated mice. Gene expression profile analysis revealed 56 genes significantly different in the treated group; these included the upregulation of p21WAF1, induction of core histone deacetylase (HDAC), and cell communication genes. Conclusion Our data demonstrate that belinostat inhibits bladder cancer and supports the clinical evaluation of belinostat for the treatment of patients with superficial bladder cancer. PMID:17935615

  20. A functional interaction between the histone deacetylase Rpd3 and the corepressor Groucho in Drosophila development

    PubMed Central

    Chen, Guoqing; Fernandez, Joseph; Mische, Sheenah; Courey, Albert J.

    1999-01-01

    The Drosophila gene groucho (gro) encodes a transcriptional corepressor that has critical roles in many development processes. In an effort to illuminate the mechanism of Gro-mediated repression, we have employed Gro as an affinity reagent to purify Gro-binding proteins from embryonic nuclear extracts. One of these proteins was found to be the histone deacetylase Rpd3. Protein–protein interaction assays suggest that Gro and Rpd3 form a complex in vivo and that they interact directly via the glycine/proline rich (GP) domain in Gro. Cell culture assays demonstrate that Rpd3 potentiates repression by the GP domain. Furthermore, experiments employing a histone deacetylase inhibitor, as well as a catalytically inactive form of Rpd3, imply that histone deacetylase activity is required for efficient Gro-mediated repression. Finally, mutations in gro and rpd3 have synergistic effects on embryonic lethality and pattern formation. These findings support the view that Gro mediates repression, at least in part, by the direct recruitment of the histone deacetylase Rpd3 to the template, where it can modulate local chromatin structure. They also provide evidence for a specific role of Rpd3 in early development. PMID:10485845

  1. A phosphorescent rhenium(I) histone deacetylase inhibitor: mitochondrial targeting and paraptosis induction.

    PubMed

    Ye, Rui-Rong; Tan, Cai-Ping; Lin, Yan-Nan; Ji, Liang-Nian; Mao, Zong-Wan

    2015-05-14

    In this report, we designed a histone deacetylase-targeted phosphorescent Re(I) complex ReLMito. Colocalization studies