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Nature Communications Jan 2017The peripheral nervous system (PNS) regenerates after injury. However, regeneration is often compromised in the case of large lesions, and the speed of axon reconnection...
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.
Topics: Animals; Axons; Benzamides; Early Growth Response Protein 2; Gene Expression Regulation; Genes, Reporter; Histone Deacetylase 1; Histone Deacetylase 2; Histone Deacetylase Inhibitors; JNK Mitogen-Activated Protein Kinases; Luciferases; Mice; Mice, Knockout; Nerve Regeneration; PAX3 Transcription Factor; Peripheral Nerve Injuries; Pyrimidines; Recovery of Function; SOXB1 Transcription Factors; Schwann Cells; Signal Transduction; Transcription Factors
PubMed: 28139683
DOI: 10.1038/ncomms14272 -
Molecular Cancer Research : MCR Jan 2018Urothelial carcinoma accounts for most of the bladder cancer cases. Using next-generation sequencing (NGS) technology, we found that a significant percentage (83%) of...
Urothelial carcinoma accounts for most of the bladder cancer cases. Using next-generation sequencing (NGS) technology, we found that a significant percentage (83%) of tumors had mutations in chromatin-remodeling genes. Here, we examined the functional relevance of mutations in two chromatin-remodeling genes, EP300 and its paralog, CREBBP, which are mutated in almost one-third of patients. Interestingly, almost half of missense mutations cluster in the histone-acetyltransferase (HAT) domain of EP300/CREBBP. This domain catalyzes the transfer of an acetyl group to target molecules such as histones, thereby regulating chromatin dynamics. Thus, patients with EP300 or CREBBP mutations may have alterations in the ability of the corresponding proteins to modify histone proteins and control transcriptional profiles. In fact, it was determined that many of the missense HAT mutations in EP300 (64%) and CREBBP (78%) were HAT-inactivating. These inactivating mutations also correlated with invasive disease in patients. Strikingly, the prediction software Mutation Assessor accurately predicted the functional consequences of each HAT missense mutation. Finally, a gene expression signature was developed that associated with loss of HAT activity and that this signature was associated with more aggressive cancer in four patient datasets. Further supporting the notion that this score accurately reflects HAT activity, we found it is responsive to treatment of cancer cells to mocetinostat, a histone deacetylase (HDAC) inhibitor. This study provides a rationale for targeted sequencing of EP300 and CREBBP and use of a gene profiling signature for predicting therapeutic response in patients. .
Topics: Cell Line, Tumor; Chromatin Assembly and Disassembly; Humans; Mutation, Missense; Urinary Bladder Neoplasms
PubMed: 28970362
DOI: 10.1158/1541-7786.MCR-17-0260 -
Stem Cell Research Jul 2019Here we utilized the chromatin in vivo assay (CiA) mouse platform to directly examine the epigenetic barriers impeding the activation of the CiA:Oct4 allele in mouse...
Here we utilized the chromatin in vivo assay (CiA) mouse platform to directly examine the epigenetic barriers impeding the activation of the CiA:Oct4 allele in mouse embryonic fibroblasts (MEF)s when stimulated with a transcription factor. The CiA:Oct4 allele contains an engineered EGFP reporter replacing one copy of the Oct4 gene, with an upstream Gal4 array in the promoter that allows recruitment of chromatin modifying machinery. We stimulated gene activation of the CiA:Oct4 allele by binding a transcriptional activator to the Gal4 array. As with cellular reprograming, this process is inefficient with only a small percentage of the cells re-activating CiA:Oct4 after weeks. Epigenetic barriers to gene activation potentially come from heavy DNA methylation, histone deacetylation, chromatin compaction, and other posttranslational marks (PTM) at the differentiated CiA:Oct4 allele in MEFs. Using this platform, we performed a high-throughput chemical screen for compounds that increased the efficiency of activation. We found that Azacytidine and newer generation histone deacetylase (HDAC) inhibitors were the most efficient at facilitating directed transcriptional activation of this allele. We found one hit form our screen, Mocetinostat, improved iPSC generation under transcription factor reprogramming conditions. These results separate individual allele activation from whole cell reprograming and give new insights that will advance tissue engineering.
Topics: Alleles; Animals; Chromatin; DNA Methylation; Epigenesis, Genetic; Histone Deacetylase Inhibitors; Induced Pluripotent Stem Cells; Mice; Octamer Transcription Factor-3; Transcriptional Activation
PubMed: 31170660
DOI: 10.1016/j.scr.2019.101470 -
BMC Genomics Feb 2024Histone acetylation, which is regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), plays a crucial role in the control of gene expression....
BACKGROUND
Histone acetylation, which is regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), plays a crucial role in the control of gene expression. HDAC inhibitors (HDACi) have shown potential in cancer therapy; however, the specific roles of HDACs in early embryos remain unclear. Moreover, although some pan-HDACi have been used to maintain cellular undifferentiated states in early embryos, the specific mechanisms underlying their effects remain unknown. Thus, there remains a significant knowledge gap regarding the application of selective HDACi in early embryos.
RESULTS
To address this gap, we treated early embryos with two selective HDACi (MGCD0103 and T247). Subsequently, we collected and analyzed their transcriptome data at different developmental stages. Our findings unveiled a significant effect of HDACi treatment during the crucial 2-cell stage of zygotes, leading to a delay in embryonic development after T247 and an arrest at 2-cell stage after MGCD0103 administration. Furthermore, we elucidated the regulatory targets underlying this arrested embryonic development, which pinpointed the G2/M phase as the potential period of embryonic development arrest caused by MGCD0103. Moreover, our investigation provided a comprehensive profile of the biological processes that are affected by HDACi, with their main effects being predominantly localized in four aspects of zygotic gene activation (ZGA): RNA splicing, cell cycle regulation, autophagy, and transcription factor regulation. By exploring the transcriptional regulation and epigenetic features of the genes affected by HDACi, we made inferences regarding the potential main pathways via which HDACs affect gene expression in early embryos. Notably, Hdac7 exhibited a distinct response, highlighting its potential as a key player in early embryonic development.
CONCLUSIONS
Our study conducted a comprehensive analysis of the effects of HDACi on early embryonic development at the transcriptional level. The results demonstrated that HDACi significantly affected ZGA in embryos, elucidated the distinct actions of various selective HDACi, and identified specific biological pathways and mechanisms via which these inhibitors modulated early embryonic development.
Topics: Pregnancy; Female; Mice; Animals; Histone Deacetylase Inhibitors; Transcriptome; Benzamides; Pyrimidines
PubMed: 38317092
DOI: 10.1186/s12864-024-10029-3 -
Cancers Sep 2021The aim of this study was to increase somatostatin type-2 receptor (SSTR2) expression on neuroendocrine tumor (NET) cells using histone deacetylase inhibitors (HDACis),...
The aim of this study was to increase somatostatin type-2 receptor (SSTR2) expression on neuroendocrine tumor (NET) cells using histone deacetylase inhibitors (HDACis), potentially increasing the uptake of SSTR2-targeted radiopharmaceuticals and subsequently improving treatment efficacy of peptide receptor radionuclide therapy (PRRT). Human NET cell lines BON-1, NCI-H727, and GOT1 were treated with HDACis (i.e., CI-994, entinostat, LMK-235, mocetinostat, panobinostat, or valproic acid (VPA); entinostat and VPA were the HDACis tested in GOT1 cells) to examine mRNA expression levels and uptake of SSTR2-targeting radiotracer [In]In-DOTATATE. Reversibility of the induced effects was examined after drug-withdrawal. Finally, the effect of VPA on radiosensitivity was investigated. A strong stimulatory effect in BON-1, NCI-H727, and GOT1 cells was observed after HDACi treatment, both on mRNA expression levels and [In]In-DOTATATE uptake. The effects of the HDACis were largely reversible over a period of seven days, demonstrating largest reductions within the first day. The reversibility profile of the induced effects suggests that proper timing of HDACi treatment is most likely essential for a beneficial outcome. In addition to increasing SSTR2 expression levels, VPA enhanced the radiosensitivity of all cell lines. In conclusion, HDACi treatment increased SSTR2 expression, and radiosensitivity was also enhanced upon VPA treatment.
PubMed: 34638389
DOI: 10.3390/cancers13194905 -
Biomedicine & Pharmacotherapy =... Jan 2019Inhibition of histone deacetylase (HDAC) suppresses inflammation of pancreatic islets and apoptosis of β-cells. However, the underlying molecular mechanism is unclear....
Inhibition of histone deacetylase (HDAC) suppresses inflammation of pancreatic islets and apoptosis of β-cells. However, the underlying molecular mechanism is unclear. In the present study, we demonstrate that MGCD0103 (MGCD), an HDAC inhibitor, protects the pancreas from streptozotocin (STZ)-induced oxidative stress and cell death. Sprague-Dawley rats were intraperitoneally injected with STZ (40 mg/kg) to induce type I diabetes. MGCD (10 μg/day) was infused with osmotic mini-pump for 4 weeks. Pancreatic insulin and macrophage infiltration were analyzed by immunohistochemistry. Cellular level of reactive oxygen species (ROS) was evaluated with fluorescence-activated cell sorting. Tetramethylrhodamine ethyl ester was used to analyze mitochondrial membrane potential. Activation of caspase-3 was analyzed by western blotting. Chromatin immunoprecipitation was performed to investigate the binding affinity of specificity protein 1 (SP1) on the promoters of target genes. mRNA expression was analyzed by quantitative real-time polymerase chain reaction. As a result, we found that MGCD infusion ameliorated STZ-induced hyperglycemia, islet deformation, decreased insulin level, and macrophage infiltration. STZ injection promoted the production of ROS, which induced caspase activity and β-cell death. 4-Hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL), a mimetic of superoxide dismutase (SOD), reduced STZ-induced caspase activity and β-cell death. MGCD treatment increased SOD expression and histone acetylation level on promoters. Infusion of MGCD promoted acetylation of SP1 and its enrichment on SOD promoters. Thus, MGCD protects pancreatic β-cells from STZ-induced oxidative stress and cell death through the induction of antioxidant enzymes such as SODs.
Topics: Animals; Benzamides; Cell Death; Dose-Response Relationship, Drug; HEK293 Cells; Hep G2 Cells; Histone Deacetylase Inhibitors; Humans; Infusion Pumps; Insulin-Secreting Cells; Male; Oxidative Stress; Pancreas; Pyrimidines; Random Allocation; Rats; Rats, Sprague-Dawley; Streptozocin
PubMed: 30551546
DOI: 10.1016/j.biopha.2018.10.163 -
Journal of Medicinal Chemistry Sep 2015A novel series of potent chiral inhibitors of histone deacetylase (HDAC) is described that contains an oxazoline capping group and a N-(2-aminophenyl)-benzamide unit....
A novel series of potent chiral inhibitors of histone deacetylase (HDAC) is described that contains an oxazoline capping group and a N-(2-aminophenyl)-benzamide unit. Among several new inhibitors of this type exhibiting Class I selectivity and potent inhibition of HDAC3-NCoR2, in vitro assays for the inhibition of HDAC1, HDAC2, and HDAC3-NCoR2 by N-(2-aminophenyl)-benzamide 15k gave respective IC50 values of 80, 110, and 6 nM. Weak inhibition of all other HDAC isoforms (HDAC4, 5, 6, 7, and 9: IC50 > 100 000 nM; HDAC8: IC50 = 25 000 nM; HDAC10: IC50 > 4000 nM; HDAC11: IC50 > 2000 nM) confirmed the Class I selectivity of 15k. 2-Aminoimidazolinyl, 2-thioimidazolinyl, and 2-aminooxazolinyl units were shown to be effective replacements for the pyrimidine ring present in many other 2-(aminophenyl)-benzamides previously reported, but the 2-aminooxazolinyl unit was the most potent in inhibiting HDAC3-NCoR2. Many of the new HDAC inhibitors showed higher solubilities and lower binding to human serum albumin than that of Mocetinostat. Increases in histone H3K9 acetylation in the human cell lines U937 and PC-3 was observed for all three oxazolinyl inhibitors evaluated; those HDAC inhibitors also lowered cyclin E expression in U937 cells but not in PC-3 cells, indicating underlying differences in the mechanisms of action of the inhibitors on those two cell lines.
Topics: Acetylation; Anilides; Apoptosis; Benzamides; Cell Cycle; Cell Line; Cell Line, Tumor; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Imidazolines; Isoenzymes; Oxazoles; Permeability; Protein Binding; Pyrimidines; Serum Albumin; Solubility; Stereoisomerism; Structure-Activity Relationship
PubMed: 26287310
DOI: 10.1021/acs.jmedchem.5b00545 -
The Journal of Pathology. Clinical... Apr 2016Histone deacetylases (HDAC) are key players in epigenetic regulation of gene expression and HDAC inhibitor (HDACi) treatment seems to be a promising anticancer therapy...
Histone deacetylases (HDAC) are key players in epigenetic regulation of gene expression and HDAC inhibitor (HDACi) treatment seems to be a promising anticancer therapy in many human tumours, including soft tissue sarcomas. HR23b has been shown to be a potential biomarker for sensitivity to HDACi therapy in cutaneous T-cell lymphoma and hepatocellular carcinoma. We aimed to evaluate HR23b as a candidate biomarker for HDACi response in sarcomas and gastrointestinal stromal tumours (GIST). Therefore, HR23b expression was analysed comprehensively by western blot in sarcoma and GIST cell lines covering all major clinically relevant subtypes. MTT assay and ApoTox-Glo(TM) Triplex assay were performed after treatment with vorinostat, belinostat, mocetinostat and entinostat. HR23b protein expression was measured under HDACi treatment. Furthermore, HR23b expression levels were immunohistochemically determined in a large set of 523 clinical samples from sarcoma and GIST patients. Western blot analyses showed that sarcomas differ significantly in their expression of HR23b protein. All HDACi were able to regulate proliferation and apoptosis in vitro. Sensitivity to vorinostat correlated significantly with HR23b protein expression. Immunohistochemical prevalence screening in clinical samples of relevant adult-type tumours revealed that 12.5% of sarcomas (among them malignant peripheral nerve sheath tumours, pleomorphic liposarcomas, leiomyosarcomas, dedifferentiated liposarcomas, synovial sarcomas and angiosarcomas) and 23.2% of GIST show high HR23b expression. Therefore, HDACi have antiproliferative and proapoptotic effects in sarcomas depending on the expression level of HR23b. These findings suggest that HR23b represents a candidate biomarker for HDACi sensitivity in certain sarcoma types and in GIST.
PubMed: 27499916
DOI: 10.1002/cjp2.35 -
CNS Neuroscience & Therapeutics Feb 2019Recently, histone deacetylase (HDAC) inhibitors are considered a possible therapeutic strategy in Alzheimer's disease (AD). However, HDACi treatments exhibit diverse...
AIMS
Recently, histone deacetylase (HDAC) inhibitors are considered a possible therapeutic strategy in Alzheimer's disease (AD). However, HDACi treatments exhibit diverse functions with unfavorable effects in AD. Thus, the development of selective HDACi without side effects is urgently needed.
METHODS
HDACi, namely, BML210, MGCD0103, PXD101, and Droxinostat, were screened in mouse hippocampal primary cultures incubated with oligomeric Aβ (50 μmol/L). MGCD0103 was chosen for in vivo tests and was intraperitoneally injected into C57BL/6J mice (0.5 mg/kg, once per day) for 4 weeks following an intrahippocampal CA1 injection of oligomeric Aβ . Brain samples were collected for pathological analyses after the behavioral analyses including open- field test (OFT), elevated plus maze (EPM), Y-maze, and Morris water maze (MWM).
RESULTS
Among the HDACi, MGCD0103 exhibited significant neuroprotection against the Aβ toxicity in primary cultures. MGCD0103 coattenuated cognitive deficits and anxiety against Aβ damage in mice. MGCD0103 further ameliorated pathological features such as the levels of acetylated histone 3 at Lys 9 site (H3K9) and α-tubulin, synaptophysin, Aβ, tau protein phosphorylation, and serotonergic neuron loss against Aβ toxicity. Furthermore, chronic MGCD0103 treatment did not show liver or kidney toxicity in mice.
CONCLUSIONS
These results reveal MGCD0103 could be a potential therapeutic agent against AD.
Topics: Amyloid beta-Peptides; Animals; Anxiety; Behavior, Animal; Benzamides; CA1 Region, Hippocampal; Cognitive Dysfunction; Female; Hippocampus; Histone Deacetylase Inhibitors; Male; Maze Learning; Mice; Mice, Inbred C57BL; Nerve Tissue Proteins; Peptide Fragments; Primary Cell Culture; Pyrimidines
PubMed: 29978554
DOI: 10.1111/cns.13029 -
Oncotarget Jul 2016Histone deacetylases (HDACs) play crucial roles in the initiation and progression of cancer, offering a promising target for cancer therapy. HDACs inhibitor MGCD0103...
Histone deacetylases (HDACs) play crucial roles in the initiation and progression of cancer, offering a promising target for cancer therapy. HDACs inhibitor MGCD0103 (MGCD) exhibits effective anti-tumor activity by blocking proliferation and inducing cell death in malignant cells. However, the molecular mechanisms of HDACs inhibition induces cell death have not been well elucidated. In this study, we showed that MGCD effectively restored histone acetylation, suppressed cell growth and induced apoptosis in two-dimensional (2D) and three-dimensional (3D) cultured CNE1 and CNE2 nasopharyngeal carcinoma (NPC) cells. Importantly, MGCD arrested cell cycle at mitosis (M) phase with formation of multipolar spindles, which was associated with activated p53-mediated postmitotic checkpoint pathway to induce apoptotic cell death. Moreover, MGCD-induced apoptosis was decreased by inhibition of p53 using short interfering RNA (siRNA), suggesting that p53 was required for MGCD-induced cell apoptosis. Consistently, MGCD in combination with Nutlin-3, a MDM2 inhibitor showed synergistic effect on inducing apoptosis in 2D and 3D cultured CNE2 cells. Collectively, our data revealed that MGCD induced p53-dependent cell apoptosis following formation of multipolar spindles in NPC cells, suggesting the therapeutic potential of combinations of HDACs and MDM2 inhibitors for NPC treatment.
Topics: Acetylation; Apoptosis; Benzamides; Cell Culture Techniques; Cell Line, Tumor; Cell Proliferation; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; M Phase Cell Cycle Checkpoints; Nasopharyngeal Neoplasms; Pyrimidines; RNA Interference; Spindle Apparatus; Tumor Suppressor Protein p53
PubMed: 27283770
DOI: 10.18632/oncotarget.9922