gsk-2816126 and Disease-Models--Animal

Topics: Adenosine; Animals; Apoptosis; Benzazepines; Bile Ducts; Carbon Tetrachloride; Cell Cycle; Cell Cycle Proteins; Cell Line; Cell Proliferation; Cellular Senescence; Cyclin-Dependent Kinase Inhibitor p21; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Enzyme Inhibitors; Hepatic Stellate Cells; Humans; Indoles; Interleukin-10; Jumonji Domain-Containing Histone Demethylases; Ligation; Liver; Liver Cirrhosis; Mice; Pyridones; Pyrimidines; Rats; RNA Interference

Topics: Animals; Cell Line; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Gene Expression; Humans; Indoles; Interferon Type I; Lupus Erythematosus, Systemic; Lupus Nephritis; Mice; Mice, Inbred NZB; Mice, Transgenic; Pyridones; Signal Transduction; Treatment Outcome

Calcitonin gene-related peptide (CGRP) as a mediator of microglial activation at the transcriptional level may facilitate nociceptive signaling. Trimethylation of H3 lysine 27 (H3K27me3) by enhancer of zeste homolog 2 (EZH2) is an epigenetic mark that regulates inflammatory-related gene expression after peripheral nerve injury. In this study, we explored the relationship between CGRP and H3K27me3 in microglial activation after nerve injury, and elucidated the underlying mechanisms in the pathogenesis of chronic neuropathic pain.. Microglial cells (BV2) were treated with CGRP and differentially enrichments of H3K27me3 on gene promoters were examined using ChIP-seq. A chronic constriction injury (CCI) rat model was used to evaluate the role of CGRP on microglial activation and EZH2/H3K27me3 signaling in CCI-induced neuropathic pain.. Overexpressions of EZH2 and H3K27me3 were confirmed in spinal microglia of CCI rats by immunofluorescence. CGRP treatment induced the increased of H3K27me3 expression in the spinal dorsal horn and cultured microglial cells (BV2) through EZH2. ChIP-seq data indicated that CGRP significantly altered H3K27me3 enrichments on gene promoters in microglia following CGRP treatment, including 173 gaining H3K27me3 and 75 losing this mark, which mostly enriched in regulation of cell growth, phagosome, and inflammation. qRT-PCR verified expressions of representative candidate genes (TRAF3IP2, BCL2L11, ITGAM, DAB2, NLRP12, WNT3, ADAM10) and real-time cell analysis (RTCA) verified microglial proliferation. Additionally, CGRP treatment and CCI increased expressions of ITGAM, ADAM10, MCP-1, and CX3CR1, key mediators of microglial activation in spinal dorsal horn and cultured microglial cells. Such increased effects induced by CCI were suppressed by CGRP antagonist and EZH2 inhibitor, which were concurrently associated with the attenuated mechanical and thermal hyperalgesia in CCI rats.. Our findings highly indicate that CGRP is implicated in the genesis of neuropathic pain through regulating microglial activation via EZH2-mediated H3K27me3 in the spinal dorsal horn.

Topics: Adaptor Proteins, Signal Transducing; Animals; Calcitonin Gene-Related Peptide; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Gene Expression; Histones; Indoles; Inflammation; Male; Methylation; Microglia; Neuralgia; Nociceptors; Peptide Fragments; Peripheral Nerve Injuries; Pyridones; Rats; Rats, Wistar; Signal Transduction; Spinal Cord

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Anti-programmed death-1 (PD-1) receptor-based therapeutics improve survival in patients with recurrent head and neck squamous cell carcinoma (HNSCC), but many do not benefit due to a low response rate. Herein, we identified EZH2 as a therapeutic target that enhanced tumor cell antigen presentation and subsequently sensitized resistant tumors to anti-PD-1 therapy.. EZH2 regulation of antigen presentation was defined using EZH2 inhibitors (GSK126 and EPZ6438) in human and mouse HNSCC cell lines. Mechanistic dissection of EZH2 in regulation of antigen presentation was investigated using flow cytometry, qRT-PCR, ELISA, and chromatin-immunoprecipitation assays.. EZH2 expression was negatively correlated with antigen-processing machinery pathway components in HNSCC data sets in The Cancer Genome Atlas. EZH2 inhibition resulted in significant upregulation of MHC class I expression in human and mouse human papillomavirus-negative HNSCC lines. Our results demonstrated that targeting EZH2 enhanced antigen presentation and was able to circumvent anti-PD-1 resistance. Thus, combining EZH2 targeting with anti-PD-1 may increase therapeutic susceptibility in HNSCC.

Topics: Animals; Antigen Presentation; Antineoplastic Agents, Immunological; Benzamides; Biphenyl Compounds; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Drug Resistance, Neoplasm; Enhancer of Zeste Homolog 2 Protein; Female; Head and Neck Neoplasms; Humans; Immunity, Cellular; Indoles; Mice; Mice, Inbred C57BL; Morpholines; Programmed Cell Death 1 Receptor; Pyridones

Upregulation of EZH2 is associated with advanced stage and poor prognosis of prostate cancer; therefore, it is likely to be a promising therapeutic target. Metformin, a drug that has been used to treat type 2 diabetes, was found to have antineoplastic activity in different cancers. Herein, we report that the combination of metformin and the EZH2 inhibitor GSK126 exerts synergistic inhibition on prostate cancer cell growth, both

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Drug Synergism; Enhancer of Zeste Homolog 2 Protein; Gene Expression Regulation, Neoplastic; Humans; Indoles; Male; Metformin; Mice; MicroRNAs; Promoter Regions, Genetic; Prostatic Neoplasms; Pyridones; Receptors, Androgen; Transcriptional Activation; Xenograft Model Antitumor Assays

Angiotensin II (Ang-II)-induced fibroblast differentiation plays an important role in the development of atrial fibrosis and atrial fibrillation (AF). Here, we show that the expression of the histone methyltransferase enhancer of zeste homolog 2 (EZH2) is increased in atrial muscle and atrial fibroblasts in patients with AF, accompanied by significant atrial fibrosis and atrial fibroblast differentiation. In addition, EZH2 is induced in murine models of atrial fibrosis. Furthermore, either pharmacological GSK126 inhibition or molecular silencing of EZH2 can inhibit the differentiation of atrial fibroblasts and the ability to produce ECM induced by Ang-II. Simultaneously, inhibition of EZH2 can block the Ang-II-induced migration of atrial fibroblasts. We found that EZH2 promotes fibroblast differentiation mainly through the Smad signaling pathway and can form a transcription complex with Smad2 to bind to the promoter region of the ACTA2 gene. Finally, our in vivo experiments demonstrated that the EZH2 inhibitor GSK126 significantly inhibited Ang-II-induced atrial enlargement and fibrosis and reduced AF vulnerability. Our results demonstrate that targeting EZH2 or EZH2-regulated genes might present therapeutic potential in AF.

Topics: Angiotensin II; Animals; Atrial Fibrillation; Disease Models, Animal; Dogs; Enhancer of Zeste Homolog 2 Protein; Female; Fibroblasts; Fibrosis; Gene Expression Regulation; Heart Atria; Humans; Indoles; Male; Mice; Middle Aged; Pyridones

Topics: Animals; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Enhancer of Zeste Homolog 2 Protein; Fusion Proteins, bcr-abl; Gene Knockdown Techniques; Humans; Indoles; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Neoplastic Stem Cells; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Pyridones; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

A close relationship between epigenetic regulation and obesity has been demonstrated in several recent studies. Histone methyltransferase enhancer of Zeste homolog 2 (Ezh2), which mainly catalyzes trimethylation of histone H3K27 to form H3K27me3 was found to be required for the differentiation of white and brown adipocytes in vitro. Here, we investigated the effects of the Ezh2-specific inhibitor GSK126 in a mouse model of obesity induced by a high-fat diet (HFD). We found that GSK126 treatment reduced body fat, improved glucose tolerance, increased lipolysis and improved cold tolerance in mice by promoting the differentiation of thermogenic beige adipocytes. Moreover, we discovered that GSK126 inhibited the differentiation of white adipocytes, and the decrease of Ezh2 enzymatic activity and H3K27me3 also changed the morphology of brown adipocytes but did not alter the expression of thermogenic genes in these cells. Our results indicated that GSK126 was a novel chemical inducer of beige adipocytes and may be a potential therapeutic agent for the management of obesity. Furthermore, they also prompted that Ezh2 and H3K27me3 play different roles in the differentiation of the white, brown, and beige adipocytes in vivo.

Topics: Adipocytes, Beige; Adipogenesis; Adipose Tissue, White; Animals; Blood Glucose; Cell Differentiation; Diet, High-Fat; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Epigenesis, Genetic; Indoles; Lipolysis; Male; Mice; Mice, Inbred C57BL; Obesity; Pyridones; Thermogenesis

Acute-on-chronic liver failure is mainly due to host immunity self-destruction. The histone H3 lysine 27 (H3K27) trimethylating enzyme, enhancer of zeste homolog 2 (EZH2) mediates epigenetic silencing of gene expression and regulates immunity, also involves pathogenesis of several liver diseases. The current study was to determine the role of methyltransferase EZH2 and its catalysed H3K27 trimethylation (H3K27me3) in liver failure, and to further investigate the potential target for liver failure treatment. EZH2 and its catalysed H3K27me3 were determined in peripheral blood mononuclear cells (PBMC) from liver failure patients and Kupffer cells from experimental mice. Furthermore, GSK126 (an inhibitor for EZH2 trimethylation function) was applied in liver failure mice in vivo, and lipopolysaccharide-stimulated mononuclear cells in vitro. EZH2 and H3K27me3 were significantly upregulated in human PBMC from liver failure patients or murine Kupffer cells from the liver failure animals, respectively. GSK126 ameliorated disease severity in liver failure mice, which maybe attribute to down-regulate circulating and hepatic proinflammatory cytokines, especially TNF via reducing H3K27me3. In-depth chromatin immunoprecipitation analysis unravelled that decreased enrichment of H3K27me3 on Tnf promotor, resulting in TNF elevation in Kupffer cells from liver failure mice. Nuclear factor kappa B (NF-κB) and protein kinase B (Akt) signalling pathways were activated upon lipopolysaccharide stimulation, but attenuated by using GSK126, accompanied with decreased TNF in vitro. In conclusion, EZH2 and H3K27me3 contributed to the pathogenesis of liver failure via triggering TNF and other indispensable proinflammatory cytokines. EZH2 was to modify H3K27me3 enrichment, as well as, activation of the downstream NF-κB and Akt signalling pathways.

Topics: Acute-On-Chronic Liver Failure; Animals; Biocatalysis; Chromatin; Cytokines; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Female; Histones; Humans; Indoles; Inflammation Mediators; Kupffer Cells; Lipopolysaccharides; Liver; Lysine; Methylation; Mice, Inbred C57BL; NF-kappa B; Promoter Regions, Genetic; Proto-Oncogene Proteins c-akt; Pyridones; Signal Transduction; Tumor Necrosis Factor-alpha

Allogeneic hematopoietic cell transplantation is often complicated by graft versus host disease (GvHD), primarily mediated through allo-reactive donor T cells in the donor stem cell graft. Enhancer of Zeste Homolog 2 (EZH2), a histone-lysine N-methyltransferase and a component of the Polycomb Repressive Complex 2, has been shown to play a role in GvHD pathology. Although not yet clear, one proposed mechanism is through selective tri-methylation of lysine 27 in histone 3 (H3K27me3) that marks the promoter region of multiple pro-apoptotic genes, leading to repression of these genes in allo-reactive T cells. We found that selective pharmacologic inhibition of H3K27me3 with EPZ6438 or GSK126 did not prevent murine GvHD. This suggests the GvHD mitigating properties of DZNep are independent from H3K27me3 inhibition. Furthermore, while pharmacologic inhibition of EZH2 by DZNep has been shown to be effective in abrogating mouse GvHD, we found that DZNep was not effective in preventing GvHD in a human T cell xenograft mouse model. Although EZH2 is an attractive target to harness donor allo-reactive T cells in the post-transplant setting to modulate GvHD and the anti-leukemia effect, our results suggest that more selective and effective ways to inhibit EZH2 in human T cells are required.

Topics: Adenosine; Animals; Benzamides; Biphenyl Compounds; Cells, Cultured; Disease Models, Animal; Enhancer of Zeste Homolog 2 Protein; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Histone Code; Histones; Humans; Indoles; Methylation; Mice; Morpholines; Pyridones; T-Lymphocytes

EZH2 is a critical epigenetic regulator that is deregulated in various types of cancers including multiple myeloma (MM). In the present study, we hypothesized that targeting EZH2 might induce apoptosis in myeloma cells including stem cell-like cells (CSCs). We investigated the effect of EZH2 inhibition on MM cells using a potent inhibitor (GSK126). The results showed that GSK126 effectively abrogated the methylated histone 3 (H3K27me3) level in MM.1S and LP1 cells, and inhibited the number of live cells and colony formation in soft agar of six MM cell lines. GSK126 induced massive apoptosis in MM.1S, LP1 and RPMI8226 cells. Progressive release of mitochondrial cytochrome c and AIF into the cytosol was detected in GSK126-treated MM cells. GSK126 treatment elicited caspase-3-dependent MCL-1 cleavage with accumulation of proapoptotic truncated MCL-1. These results suggested that GSK126 triggers the intrinsic mitochondrial apoptosis pathway. Enhanced apoptosis was observed in the combination of GSK126 with bortezomib. Using ALDH and side population (SP) assays to characterize CSCs, we found that GSK126 eliminated the stem-like myeloma cells by blocking the Wnt/β-catenin pathway. The in vivo anti-tumor effect of GSK126 was confirmed by using RPMI8226 cells in a xenograft mouse model. In conclusion, our findings suggest that EZH2 inactivation by GSK126 is effective in killing MM cells and CSCs as a single agent or in combination with bortezomib. Clinical trial of GSK126 in patients with MM may be warranted.

Topics: Animals; Apoptosis; Bortezomib; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Drug Synergism; Enhancer of Zeste Homolog 2 Protein; Enzyme Activation; Humans; Indoles; Male; Mice; Mitochondria; Multiple Myeloma; Myeloid Cell Leukemia Sequence 1 Protein; Neoplastic Stem Cells; Proteolysis; Pyridones; Wnt Signaling Pathway; Xenograft Model Antitumor Assays