Search Results (79)

Childhood neuroblastoma (NB) is a malignant tumour that is a member of a class of embryonic tumours that have their origins in sympathoadrenal progenitor cells. There are five stages in the clinical NB staging system: 1, 2A, 2B, 3, 4S, and 4. For those diagnosed with stage 4 neuroblastoma (NBS4), the treatment options are limited with a survival rate of between 40 and 50%. Since 1975, more than 15 targets have been identified in the search for a treatment for high-risk NBS4. This article is concerned with the search for a multi-target drug treatment for high-risk NBS4 and focuses on four possible treatment targets that research has identified as having a role in the development of NBS4 and includes the inhibitors Histone Deacetylase (HDAC), Bromodomain (BRD), Hedgehog (HH), and Tropomyosin Kinase (TRK). Computer-aided drug design and molecular modelling have greatly assisted drug discovery in medicinal chemistry. Computational methods such as molecular docking, homology modelling, molecular dynamics, and quantitative structure–activity relationships (QSAR) are frequently used as part of the process for finding new therapeutic drug targets. Relying on these techniques, the authors describe a medicinal chemistry strategy that successfully identified eight compounds (inhibitors) that were thought to be potential inhibitors for each of the four targets listed above. Results revealed that all four targets BRD, HDAC, HH and TRK receptors binding sites share similar amino acid sequencing that ranges from 80 to 100%, offering the possibility of further testing for multi-target drug use. Two additional targets were also tested as part of this work, Retinoic Acid (RA) and c-Src (Csk), which showed similarity (of the binding pocket) across their receptors of 80–100% but lower than 80% for the other four targets. The work for these two targets is the subject of a paper currently in progress. Full article

Type 1 diabetes (T1D) is a chronic metabolic disease defined by sustained hyperglycemia, leading to oxidative stress (OS) and systemic complications, including male subfertility. This study investigates the potential impact of T1D-induced OS on microtubule (MTs) dynamics and microtubule-associated proteins (MAPs) in the testis and spermatozoa (SPZ). Using a streptozotocin-induced T1D rat model, we examined the expression and localization of key MAPs, including Microtubule Affinity-Regulating Kinase 4 (MARK4), Microtubule-Associated Protein 1A (MAP1A), Dynein Light Chain LC8-Type 1 (DYNLL1), Prolyl Endopeptidase (PREP), and Radial Spoke Head 6 Homolog A (RSPH6A), alongside sperm functional parameters. Our findings showed that T1D significantly impaired the expression and distribution of these proteins, which may affect MTs organization and be associated with cytoskeletal disorganization, and impaired germ cell differentiation. Moreover, T1D rats exhibited reduced sperm count, viability, and motility, accompanied by increased DNA fragmentation and chromatin defects. Elevated levels of 4-hydroxy-2-nonenal (4-HNE), a marker of OS, were detected in SPZ, particularly in the acrosome and flagellum, correlating with mitochondrial dysfunction and ATP depletion. Additionally, decreased intracellular Ca²⁺ levels, downregulation of Cation Channel of Sperm (CATSPER) and Voltage-Dependent Anion Channel 3 (VDAC3), and altered tubulin acetylation, possibly due to imbalanced Alpha-Tubulin N-Acetyltransferase 1 (ATAT1) and Histone Deacetylase 6 (HDAC6) expression, were also associated with impaired sperm motility. The combined data suggest that T1D-induced OS is linked to disrupted MTs dynamics, which may contribute to testicular dysfunction and reduced sperm quality, potentially affecting male fertility. A better understanding of these associations may support the development of therapeutic strategies to mitigate the reproductive consequences of T1D and improve male fertility outcomes. Full article

This study investigated whether the supplementation of prebiotic inulin to gestating sows programmatically affects offspring growth performance and meat quality while exploring its epigenetic effects through histone acetylation modulation. After mating, sixty multiparous sows (Landrace × Yorkshire; parity 2–3) were assigned to a 2 × 2 factorial arrangement with inulin (0% vs. 1.5%) and fat (0% or 5%) supplementation until farrowing. Post-weaning, five litters (10 piglets per litter) per treatment were selected and maintained in their original litter for fattening under standardized feeding. The results demonstrated that maternal inulin supplementation during gestation accomplished the following: (1) Increased offspring liver index by 13.4% at weaning and 6.8% at finishing (p < 0.05) while reducing the finishing-phase backfat thickness by 11.6% (p < 0.01), with a significant inulin × fat interaction attenuating fat-induced abdominal lipid accumulation at weaning (p = 0.05). (2) Decreased longissimus dorsi muscle lightness (L*) by 4.5% in finishing pigs (p = 0.02) without altering the other meat quality parameters. (3) Suppressed offspring liver lipid deposition at birth and finishing (p < 0.05), concomitant with upregulated hepatic PGC-1α and CPT1A expression (p < 0.05). (4) Elevated neonatal serum butyrate by 15.6% (p = 0.06) while inhibiting hepatic histone deacetylase (HDAC) activity and enhancing histone H3/H4 acetylation (p < 0.01). These findings suggest that maternal inulin supplementation during gestation mitigates offspring hepatic lipid deposition through butyrate-mediated epigenetic regulation, where microbial-derived butyrate from inulin fermentation inhibits HDAC activity, enhances histone acetylation levels, and upregulates fatty acid β-oxidation gene expression. This study provides novel mechanistic insights into how maternal dietary fiber nutrition programs offspring development through epigenetic reprogramming. Full article

Precise binding free-energy predictions for ligands targeting metalloproteins, especially zinc-containing histone deacetylase (HDAC) enzymes, require specialized computational approaches due to the unique interactions at metal-binding sites. This study evaluates a docking algorithm optimized for zinc coordination to determine whether it could accurately differentiate between protonated and deprotonated states of hydroxamic acid ligands, a key functional group in HDAC inhibitors (HDACi). By systematically analyzing both protonation states, we sought to identify which state produces docking poses and binding energy estimates most closely aligned with experimental values. The docking algorithm was applied across HDAC 2, 4, and 8, comparing protonated and deprotonated ligand correlations to experimental data. The results demonstrate that the deprotonated state consistently yielded stronger correlations with experimental data, with R² values for deprotonated ligands outperforming protonated counterparts in all HDAC targets (average R² = 0.80 compared to the protonated form where R² = 0.67). These findings emphasize the significance of proper ligand protonation in molecular docking studies of zinc-binding enzymes, particularly HDACs, and suggest that deprotonation enhances predictive accuracy. The study’s methodology provides a robust foundation for improved virtual screening protocols to evaluate large ligand libraries efficiently. This approach supports the streamlined discovery of high-affinity, zinc-binding HDACi, advancing therapeutic exploration of metalloprotein targets. A comprehensive, step-by-step tutorial is provided to facilitate a thorough understanding of the methodology and enable reproducibility of the results. Full article

Background: Histone deacetylase 4 (HDAC4) is a member of the class II histone deacetylase family, whose members play a crucial role in various biological processes. An in-depth investigation of the transcriptional characteristics of chicken HDAC4 can provide fundamental insights into its function. Methods: We examined HDAC4 expression in chicken embryonic stem cells (ESC) and spermatogonial stem cells (SSC) and cloned a 444 bp fragment from upstream of the chicken HDAC4 transcription start site. Subsequently, we constructed pEGFP-HDAC4 and a series of 5′-deletion luciferase reporter constructs, which we transfected into DF-1 cells to measure their transcriptional activity. The regulatory mechanisms of chicken HDAC4 expression were investigated by performing trichostatin A (TSA) treatment, deleting putative transcription factor binding sites, and altering transcription factor expression levels. Results: HDAC4 exhibited higher expression in SSC than in ESC. We confirmed that the upstream region from −295 bp to 0 bp is the core transcriptional region of HDAC4. TSA effectively inhibited HDAC4 transcription, and bioinformatics analysis indicated that the chicken core HDAC4 promoter sequence exhibits high homology with those of other avian species. The myelocytomatosis viral oncogene homolog (MYC) and hypoxia-inducible factor 1 α (HIF1A) transcription factors were predicted to bind to this core region. Treatment with TSA for 24 h resulted in the upregulation of MYC and HIF1A, which repressed HDAC4 transcription. Conclusions: Our results provide a basis for subsequent investigations into the regulation of HDAC4 expression and biological function. Full article

Diffuse Large B-cell Lymphoma (DLBCL) is the most common aggressive non-Hodgkin lymphoma (NHL). Despite the use of newer agents, such as polatuzumab vedotin, more than one-third of patients have ultimately relapsed or experienced refractory disease. MiRNAs are single-stranded, ~22-nucleotide-long RNAs that interact with their target RNA. They are significant regulators of post-transcriptional gene expression. One significant miRNA, miR-155, is involved in the pathophysiology of DLBCL and it is a critical modulator of hematopoiesis, inflammation, and immune responses. Targets of miR-155, such as histone deacetylase 4 (HDAC4), suppressor of cytokine signaling-1 (SOCS1) and immune cells, play a crucial role in DLBCL pathogenesis, since miR-155 regulates key pathways, transcription factors and cytokine expression and shapes the tumor microenvironment in DLBCL. In this review, we examine the role of miR-155 in DLBCL and its potential as a future diagnostic, prognostic, or predictive biomarker. Full article

Objective: Previous drug repositioning studies have suggested that parthenolide may be a differentiation-inducing agent for glioma cells. This study aimed to experimentally verify the neuronal differentiation-inducing effects and proliferative impact of parthenolide on human glioma cells and explore its potential mechanisms. Methods: HE staining was used to observe the morphological changes in human glioma cell lines U87 and A172 induced by parthenolide. Immunocytochemistry was conducted to detect the expression of differentiation markers. The Ki-67 detection and CCK-8 assay were used to assess the effects of parthenolide on cell proliferation. The sphere formation assay was conducted to evaluate the self-renewal. Glioma stem cells (GSCs) derived from U87 cells were utilized to assess the ability of parthenolide to induce differentiation in GSCs. Western blot was used to detect the expression of histone deacetylase 1 (HDAC1). Bioinformatics analysis based on the CGGA database was conducted to evaluate the role of HDAC1 in glioma. Results: Parthenolide (4 μM) altered the morphology of U87 and A172 cells, as elongated cell projections were observed. Parthenolide induced glioma cells to express neuronal markers NeuN, MAP2, SYP, and NEFL, but not astrocyte or oligodendrocyte markers. Parthenolide significantly inhibited proliferation and self-renewal in glioma cells. Similar effects were observed in U87 GSCs. Furthermore, parthenolide downregulated HDAC1 expression in glioma cells, and the bioinformatics analysis revealed a potential relationship between neuronal characteristics and low expression of HDAC1 in glioma. Conclusion: Parthenolide induced neuronal differentiation and inhibited the cell proliferation in human glioma cells, which might be associated with the inhibition of HDAC1. Full article

Background/Objectives: High fructose has been implicated as an important trigger of kidney inflammation in patients and experimental models. Magnolol, isolated from Magnolia officinalis, has an anti-inflammatory effect, but its protective role in podocytes remains underexplored. This study explored the protective effects and underlying mechanism of magnolol against high fructose-induced podocyte inflammation. Methods: The effects of magnolol on high fructose-induced podocyte inflammation were assessed in male Sprague Dawley rats administered 10% (w/v) fructose water for 12 weeks and heat-sensitive human podocyte cell lines (HPCs) exposed to 5 mM fructose. Podocyte foot processes were examined using transmission electron microscopy. The expression levels of nephrin, podocin, tumor necrosis factor-α (TNF-α), Notch1 intracellular domain (NICD1), triokinase/FMN cyclase (TKFC), specificity protein 1 (Sp1) and histone deacetylase 4 (HDAC4) were determined by Western blot, immunofluorescence and real-time quantitative polymerase chain reaction (qRT-PCR). The chromatin immunoprecipitation (ChIP) assay was performed to evaluate the interaction between Sp1 and the promoter region of HDAC4. Results: Magnolol mitigated the impairment of glomerular filtration function in high fructose-fed rats. Besides, it significantly alleviated the inflammatory responses in glomeruli and HPCs, evidenced by decreased protein levels of TNF-α and NICD1. Increased protein levels of TKFC, Sp1 and HDAC4 were observed in high fructose-stimulated HPCs and rat glomeruli. TMP195, an HDAC4 inhibitor, reduced TNF-α and NICD1 protein levels in high fructose-exposed HPCs. The increased Sp1 was shown to associate with the promoter region of HDAC4, promoting HDAC4 protein expression in high fructose-exposed HPCs. The knockdown of TKFC in HPCs by TKFC siRNA decreased Sp1, HDAC4 and NICD1 protein levels, alleviating podocyte inflammatory response. Furthermore, magnolol inhibited TKFC/Sp1/HDAC4/Notch1 activation in vivo and in vitro. Conclusions: Magnolol attenuated high fructose-induced podocyte inflammation possibly through the suppression of TKFC/Sp1/HDAC4/Notch1 activation, providing new evidence for its potential role in podocyte protection. Full article

Histone deacetylases (HDACs) are important cancer drug targets. Existing FDA-approved drugs target the catalytic pocket of HDACs, which is conserved across subfamilies (classes) of HDAC. However, engineering specificity is an important goal. Herein, we use molecular modeling approaches to identify and target potential novel pockets specific to Class IIA HDAC-HDAC4 at the interface between HDAC4 and the transcriptional corepressor component protein NCoR. These pockets were screened using an ensemble docking approach combined with consensus scoring to identify compounds with a different binding mechanism than the currently known HDAC modulators. Binding was compared in experimental assays between HDAC4 and HDAC3, which belong to a different family of HDACs. HDAC4 was significantly inhibited by compound 88402 but not HDAC3. Two other compounds (67436 and 134199) had IC50 values in the low micromolar range for both HDACs, which is comparable to the known inhibitor of HDAC4, SAHA (Vorinostat). However, both of these compounds were significantly weaker inhibitors of HDAC3 than SAHA and thus more selective, albeit to a limited extent. Five compounds exhibited activity on human breast carcinoma and/or urothelial carcinoma cell lines. The present result suggests potential mechanistic and chemical approaches for developing selective HDAC4 modulators. Full article

Epigenetic modulation, including histone modification, alters gene expression and controls cell fate. Histone deacetylases (HDACs) are identified as important regulators of dental pulp cell (DPC) mineralisation processes. Currently, there is a paucity of information regarding the nature of histone modification and HDAC expression in the dentine–pulp complex during dentinogenesis. The aim of this study was to investigate post-translational histone modulation and HDAC expression during DPC mineralisation and the expression of Class I/II HDACs during tooth development and in adult teeth. HDAC expression (isoforms −1 to −6) was analysed in mineralising primary rat DPCs using qRT-PCR and Western blot with mass spectrometry being used to analyse post-translational histone modifications. Maxillary molar teeth from postnatal and adult rats were analysed using immunohistochemical (IHC) staining for HDACs (1–6). HDAC-1, -2, and -4 protein expression increased until days 7 and 11, but decreased at days 14 and 21, while other HDAC expression increased continuously for 21 days. The Class II mineralisation-associated HDAC-4 was strongly expressed in postnatal sample odontoblasts and DPCs, but weakly in adult teeth, while other Class II HDACs (-5, -6) were relatively strongly expressed in postnatal DPCs and adult odontoblasts. Among Class I HDACs, HDAC-1 showed high expression in postnatal teeth, notably in ameloblasts and odontoblasts. HDAC-2 and -3 had extremely low expression in the rat dentine–pulp complex. Significant increases in acetylation were noted during DPC mineralisation processes, while trimethylation H3K9 and H3K27 marks decreased, and the HDAC-inhibitor suberoylanilide hydroxamic acid (SAHA) enhanced H3K27me3. These results highlight a dynamic alteration in histone acetylation during mineralisation and indicate the relevance of Class II HDAC expression in tooth development and regenerative processes. Full article

Background: Histone deacetylases (HDACs) are implicated in carcinogenesis, and HDAC inhibitors (HDACis) are explored as a therapeutic tool in several tumors. The aim of this study was to evaluate the clinical significance of HDAC-2, -4, and -5 expression in epithelial ovarian carcinoma (EOC). Methods: HDAC-2, -4, and -5 immunohistochemical expression was examined in 92 EOC tissue specimens and was correlated with clinicopathological characteristics. Results: HDAC-2 was the most frequently (94.4%) expressed isoform, being marginally higher in serous tumors compared with other types (p = 0.08). HDAC-5 was the less frequently expressed (28.1%), being positively associated with HDAC-4. HDAC-4 positivity was associated with lower FIGO-stage (p = 0.045) and T-category (p = 0.043) and the absence of lymph node (p = 0.05) or distant metastasis (p = 0.09) in serous carcinomas. HDAC-2 positivity was correlated with the absence of lymph node metastasis in serous tumors (p = 0.045). On the contrary, HDAC-5 nuclear positivity was correlated with lymph node metastasis in the entire cohort (p = 0.048). HDAC-4 positivity was marginally associated with favorable prognosis in serous carcinomas in univariate survival analysis (p = 0.086), but this correlation was not significant in multivariate analysis. Conclusions: These findings suggest a differential expression among HDAC-2, -4, and -5 in ovarian adenocarcinomas in terms of immunolocalization, positivity rate, and associations with clinicopathological parameters, providing evidence for a potential role in the pathobiology of EOC. Full article

Background: Programmed death-ligand 1 (PD-L1) expression in neoplastic and immune cells of the tumor microenvironment determines the efficacy of antitumor immunity, while it can be regulated at the epigenetic level by various factors, including HDACs. In this study, we aim to evaluate the expression patterns of PD-L1 in thymic epithelial tumors (TETs), while we attempt the first correlation analysis between PD-L1 and histone deacetylases (HDACs) expression. Methods: Immunohistochemistry was used to evaluate the expression of PD-L1 in tumor and immune cells of 91 TETs with SP263 and SP142 antibody clones, as well as the expressions of HDCA1, -2, -3, -4, -5, and -6. Results: The PD-L1 tumor proportion score (TPS) was higher, while the immune cell score (IC-score) was lower in the more aggressive TET subtypes and in more advanced Masaoka–Koga stages. A positive correlation between PD-L1 and HDAC-3, -4, and -5 cytoplasmic expression was identified. Conclusions: Higher PD-L1 expression in neoplastic cells and lower PD-L1 expression in immune cells of TETs characterizes more aggressive and advanced neoplasms. Correlations between PD-L1 and HDAC expression unravel the impact of epigenetic regulation on the expression of immune checkpoint molecules in TETs, with possible future applications in combined therapeutic targeting. Full article

Increased oxidative stress (OS) and systemic inflammation are key players in the pathophysiology of chronic obstructive pulmonary disease (COPD). We aimed to clarify the effects of synthetic glutathione (GSH) analogue peptides UPF1 and UPF17 on the mRNA levels of enzymes involved in systemic inflammation and GSH metabolism in peripheral blood mononuclear cells (PBMCs) from patients with acute exacerbation of COPD (AE-COPD) and stable COPD along with non-obstructive smokers and non-smokers. UPF1 and UPF17 increased the expression of enzymes involved in the formation of the antioxidant capacity: superoxide dismutase 1 (SOD1) and the catalytic subunit of glutamyl-cysteine ligase (GCLC) in patients with AE-COPD and stable COPD, but also in non-obstructive smokers and non-smokers. Similarly, both UPF1 and UPF17 increased the expression of inflammatory enzymes poly(ADP-ribose) polymerase-1 (PARP-1), dipeptidyl peptidase 4 (DPP4), and cyclooxygenase-2 (COX-2). Both UPF analogues acted in a gender-dependent manner by increasing the expression of certain anti-inflammatory (histone deacetylase 2 (HDAC2)) and GSH metabolism pathway (SOD1 and GSH reductase (GSR))-related enzymes in females and decreasing them in males. UPF1 and UPF17 are able to increase the expression of the enzymes involved in GSH metabolism and could serve as a lead for designing potential COPD therapies against excessive OS. Full article

Background: This phase II study evaluated the efficacy and safety of the histone deacetylase (HDAC) inhibitor, vorinostat, administered in combination with paclitaxel and carboplatin in patients with platinum sensitive recurrent ovarian cancer. Methods: Women with recurrent platinum-sensitive ovarian, peritoneal, or Fallopian tube carcinoma, a performance status of 0–2, and good overall organ function were eligible. Patients received 6 courses of paclitaxel (175 mg/m²) and carboplatin area under the curve (AUC) of 5.0 mg/mL/min administered via intravenous infusion on day 1 of a 3-week schedule. In addition, patients received vorinostat 400 mg orally once daily on days −4 through 10 of Cycle 1 and days 1 through 14 of each subsequent treatment cycle. The primary endpoints were progression-free survival (PFS) and adverse events. The secondary endpoints were the objective response rate and overall survival. Results: Fifty-five patients were included. CR was obtained in 14 patients (26.4%) and PR in 19 patients (35.8%), resulting in an ORR of 62.2%. Twenty patients (37.7%) had SD. The median duration of response (DoR) was 12.6 (range 6–128) months. The median PFS was 11.6 months (95% CI, 10.3–18.0; p < 0.001). Median OS was 40.6 months (95% Cl, 25.1–56.1). The most common treatment-related adverse events (all grades) were fatigue, anemia, thrombocytopenia, neutropenia, anorexia, nausea, pain, sensory neuropathy, myalgia, stomatitis and diarrhea. Conclusions: Vorinostat combined with carboplatin plus paclitaxel was tolerable and generated significant responses including a long median overall survival in recurrent platinum-sensitive ovarian cancer. Full article

Skeletal muscle development remarkably affects meat production and growth rate, regulated by complex regulatory mechanisms in pigs. Specific AT sequence-binding protein 2 (SATB2) is a classic transcription factor and chromatin organizer, which holds a profound effect in the regulation of chromatin remodeling. However, the regulation role of SATB2 concerning skeletal muscle cell fate through chromatin remodeling in pigs remains largely unknown. Here, we observed that SATB2 was expressed higher in the lean-type compared to the obese-type pigs, which also enriched the pathways of skeletal muscle development, chromatin organization, and histone modification. Functionally, knockdown SATB2 led to decreases in the proliferation and migration markers at the mRNA and protein expression levels, respectively, while overexpression SATB2 had the opposite effects. Further, we found histone deacetylase 4 (HDAC4) was a key downstream target gene of SATB2 related to chromatin remodeling. The binding relationship between SATB2 and HDAC4 was confirmed by a dual-luciferase reporter system and ChIP-qPCR analysis. Besides, we revealed that HDAC4 promoted the skeletal muscle cell proliferation and migration at the mRNA and protein expression levels, respectively. In conclusion, our study indicates that transcription factor SATB2 binding to HDAC4 positively contributes to skeletal muscle cell proliferation and migration, which might mediate the chromatin remodeling to influence myogenesis in pigs. This study develops a novel insight into understanding the molecular regulatory mechanism of myogenesis, and provides a promising gene for genetic breeding in pigs. Full article