Histone Deacetylase Enzymes Research Articles

Pioneering first-in-class HDAC-ROCK inhibitors as potential multitarget anticancer agents.

With the aim of simultaneously modulating the epigenetic system and the protein kinase pathway, we selected the enzyme histone deacetylase (HDAC) and the Rho-associated protein kinases (ROCK) as desired targets to develop potential multitarget anticancer agents with additional antimetastatic properties. We report here the rational design, synthesis, and biological evaluation of the first-in-class HDAC/ROCK multitarget inhibitors in pancreatic ductal adenocarcinoma (PDAC) and triple-negative breast cancer (TNBC). A molecular docking study performed with the Gold software was used to develop HDAC/ROCK multitarget inhibitors. IC50 values were determined by enzyme assays. The cytotoxicity, anti-migratory and anti-invasive properties of the inhibitors were evaluated using triple-negative breast cancer cells (MDA-MB-231 and HCC 1973) and pancreatic ductal adenocarcinoma cells (Panc-1 and MiaPaCa-2). C-9 showed significant inhibition of HDAC6, ROCK1 and ROCK2. At the same time, this compound showed strong antiproliferative effects on MDA-MB-231, MiaPaCa-2 and Panc-1 cell lines with IC50 values of 5.81 μM, 3.87 μM and 19.57 μM. In addition, it demonstrated great anti-invasive and anti-migratory effects. The findings of this study strongly suggest that the simultaneous inhibition of ROCK and HDACs holds significant potential as a promising therapeutic strategy in the advancement of cancer treatment.

The class-IIa HDAC inhibitor TMP269 promotes BMP-Smad signalling and is neuroprotective in in vitro and in vivo 6-hydroxydopamine models of Parkinson's disease.

Degeneration of midbrain nigrostriatal dopaminergic neurons is a pathological hallmark of Parkinson's disease (PD). Peripheral delivery of a compound(s) to arrest or slow this dopaminergic degeneration is a key therapeutic goal. Pan-inhibitors of histone deacetylase (HDAC) enzymes, key epigenetic regulators, have shown therapeutic promise in PD models. However as there are several classes of HDACs (ClassI-IV), class-specific inhibition will be important to ensure target specificity. Here we examine the neuroprotective potential of the Class-IIa HDAC inhibitor, TMP269. We show that TMP269 protects against 6-hydroxydopamine (6-OHDA)-induced neurite injury in SH-SY5Y cells and cultured rat ventral mesencephalic dopaminergic neurons. We find that TMP269 upregulates the neurotrophic factor BMP2 and BMP-Smad dependent transcription signalling in SH-SY5Y cells, which was necessary for its neuroprotective effect against 6-OHDA-induced injury. Furthermore, peripheral continuous infusion of 0.5mg/kg of TMP269 for 7 days via a mini-osmotic pump, reduced forelimb impairments induced by striatal 6-OHDA administration. TMP269 also protected dopaminergic neurons in the substantia nigra and their striatal terminals from striatal 6-OHDA-induced neurodegeneration and prevented the 6-OHDA-induced increases in the numbers of IBA1-positive microglia in the striatum and substantia nigra in vivo. TMP269 also prevented 6-OHDA-induced decreases in the BMP2, pSmad1/5 and acetylated histone 3 levels, and it reversed 6-OHDA-induced increase in nuclear HDAC5 in dopamine neurons in the substantia nigra. These data add to the growing body of evidence that of Class-IIa specific HDAC inhibitors may be pharmacological agents of interest for peripheral delivery with the goal of neuroprotection in PD.

Enhancing HDAC Inhibitor Screening: Addressing Zinc Parameterization and Ligand Protonation in Docking Studies.

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.

Targeting histone acetylation to overcome drug resistance in the parasite Trichomonas vaginalis.

Trichomoniasis, caused by the parasite Trichomonas vaginalis, is the most common non-viral sexually transmitted infection. Current treatment relies exclusively on 5-nitroimidazole drugs, with metronidazole (MTZ) as the primary option. However, the increasing prevalence of MTZ-resistant strains poses a significant challenge, particularly in the current absence of alternative therapies. Several studies have revealed that the development of metronidazole resistance in T. vaginalis is linked to genomic and transcriptional alterations. Given the role of epigenetic regulation in controlling gene expression, we investigated whether targeting histone deacetylase (HDAC) enzymes could influence drug resistance. Treatment of an MTZ-resistant strain (B7268) with the HDAC inhibitor, trichostatin A (TSA), in combination with MTZ enhanced drug sensitivity and induced significant genome-wide transcriptional changes, as revealed by RNA-seq analysis. To identify drug-related genes epigenetically silenced in the resistant strain but highly active in a sensitive strain, we compared the expression levels of the genes affected by TSA and MTZ treatment with their baseline expression profiles in both resistant and sensitive strains. This analysis identified 130 candidate genes differentially expressed in the sensitive strain NYH209, less expressed in the resistant B7268 strain, that exhibited significant expression changes upon TSA and MTZ treatment. Functional validation involved transfecting the B7268 strain with plasmids encoding four individual candidate genes: a thioredoxin reductase (TrxR), a cysteine synthase (CS), and two genes containing Myb domains (Myb5 and Myb6). Overexpression of three of these genes resulted in a marked reduction in MTZ resistance, demonstrating their role in modulating drug sensitivity. Our findings identified three novel genes that modulate drug resistance in T. vaginalis. This study reveals a previously unknown epigenetic mechanism underlying drug resistance and highlights the therapeutic potential of targeting epigenetic factors, such as HDACs, to overcome resistance and improve treatment efficacy.

Evaluation of the Effects of HDAC Activity in Hydroxychloroquine Applied Human Primary Chondrocyte and Nucleus Pulposus Cultures.

To evaluate the in vitro effects of hydroxychloroquine (HCQ) on histone deacetylase (HDAC) enzyme activity and interleukin (IL)-6, IL-10, and tumor necrosis factor-alpha (TNF-α) expressions. Primary cell cultures were prepared. Samples that did not receive any medication constituted the control group, while culture samples treated with HCQ served as the study group. The surface morphology of cells and the extracellular matrix (ECM) were evaluated by Giemsa staining and inverted light microscopy. Cell viability, proliferation, and cytotoxicity were determined by 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyltetrazolium-bromide (MTT) analysis. The cultures were simultaneously stained with acridine orange (AO)/propidium iodide (PI) and viewed under fluorescence microscopy. HDAC enzyme activity and IL-6, IL-10, and TNF-α expression were evaluated using commercial enzyme-linked immunosorbent assay kits. The obtained data were analyzed using statistical methods. The alpha significance level was accepted as p < 0.05. HCQ applied to cell cultures at the tested doses and durations showed cytotoxic effects on cell viability, proliferation, and cell or ECM morphology. It increased HDAC activity in chondrocytes and caused a proinflammatory response, indicated by an increase in TNF-α in the cells (p < 0.05). The results of this study emphasized that the cytotoxic effect of HCQ increased HDAC activity; therefore, this proinflammatory response should be taken into consideration in the clinical use of HCQ.

Synthesis and Evaluation of 9-epi-Koshidacin B as Selective Inhibitor of Histone Deacetylase 1.

A concise synthetic route to an epimer of the recently isolated biologically active cyclic tetrapeptide koshidacin B has been developed, which featured a late-stage functionalization of a macrocyclic scaffold through a cross metathesis reaction. The synthetic 9-epi-koshidacin B showed marginal differences in spectroscopic behavior with that of the natural product but exhibited conformational preferences similar to those reported for analogous substrate chlamydocin. Moreover, it exhibited a useful level of selective inhibition of biologically relevant enzyme histone deacetylase 1 with an IC50 value of 0.145 μM over two other isoforms. Docking studies indicate that the natural product as well as its 9-epimer binds very similarly to the active site of HDAC1 indicating little influence of the configuration of the C9-stereocenter.

Drosophila Sirtuin 1 plays a neuroprotective role in altering Alzheimer’s disease-related pathologies in flies

Sirtuin, a Class III histone deacetylase enzyme dependent on nicotinamide adenine dinucleotide, plays a pivotal role in aging and age-related diseases. Numerous studies have highlighted the involvement of sirtuins in Alzheimer&amp;rsquo;s and other neurodegenerative diseases; however, their molecular mechanisms and possible interactions with Alzheimer&amp;rsquo;s disease (AD)-associated genes remain unclear. In this study, using a Drosophila melanogaster model of AD, we investigated the potential genetic interactions between sirtuin and AD-associated genes, including amyloid-beta 42, Appl, and Tau. Our findings show that the overexpression or downregulation of Drosophila Sirtuin 1 alters AD-related pathologies such as the rough eye phenotype, behavioral impairments, and excessive cell death observed in AD model flies. In addition, the observed rescue of AD pathologies appears to be associated with sirtuin overexpression, which modulates c-Jun N-terminal kinase and Notch signaling pathways in flies. These findings show that Sirtuin1 plays a neuroprotective role in AD.

Fluoride induces immune-inflammatory disorder in the kidneys via histone lysine crotonylation in vivo

Fluoride is an essential trace element for human. Adequate levels of fluoride are crucial for maintaining skeletal growth, but excessive fluoride exposure entering the body can cause renal damage, including damaged renal tubules and impaired renal function. However, the mechanism on fluoride-induced kidney injury remains unclear. This study aimed to explore the immune-inflammatory imbalance induced by fluoride and its possible mechanism in the kidneys. Mice were exposed to sodium fluoride (NaF) (0, 25, 50 and 100 mg/L) for five months. The results showed that NaF increased the renal weight and renal index. The NaF-treated groups exhibited higher serum creatinine (Cre), blood urea nitrogen (BUN), albumin (ALB) total protein (TP) levels. Further, NaF increased reactive oxygen species (ROS) levels, lipid peroxidation (LPO) levels and malondialdehyde (MDA) level. Superoxide dismutase (SOD) activity was reduced and glutathione (GSH) activities were reduced in fluoride-treated group. NaF treatment also downregulated the nuclear factor E2-related factor (Nrf2) protein and its downstream enzymes heme oxygenase-1 (HO-1) and NAD(P)H: Quinone Oxidoreductase 1(NQO1) in the kidneys. Further, NaF shifted Th1/Th2 balance toward Th1 bias. Similarly, NaF exhibited increased macrophages and augmented M1 differentiation but suppressed M2 differentiation. The renal inflammatory response was also induced by fluoride via activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and increase of the pro-inflammatory factors tumour necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), interleukin-6 (IL-6) and interleukin-18 (IL-18). In addition, NaF treatment reduced the expression of the histone 2B lysine 12 crotonylation (H2BK12cr) and H4K8cr proteins as well as decreased the histone acetyltransferase P300 protein. NaF incresed the protein expression of histone decrotonylation enzyme sirtuin1 (sirt1) and histone deacetylase 3 (HDAC3) and upregulated HDAC2 protein. These findings demonstrate that fluoride exposure induces renal dysfunction and oxidative injury, affects M1/M2 polarization and Th1/Th2 differentiation, and promotes the inflammatory response via histone lysine crotonylation, ultimately resulting in nephrotoxicity.

Discovery of New Thiourea Derivatives as Potential SIRT Inhibitors

Objective: This study aimed to design and synthesize novel thiourea-based compounds targeting Sirtuins (SIRTs), a class of histone deacetylase enzymes implicated in various cellular processes, including cancer, and to evaluate their cytotoxic potential against colon cancer cells. Methods: Virtual modeling and molecular docking studies were conducted to design the compounds and assess their interaction with SIRT enzymes. Compounds showing acceptable docking scores were selected for organic synthesis. The final compounds (MA-1 to MA-6) were synthesized and characterized using FTIR, ¹H-NMR, and ¹³C-NMR spectroscopy. Cytotoxicity studies were performed on SW480 colon cancer cells to evaluate the biological activity of the synthesized compounds. Results: All synthesized compounds exhibited promising cytotoxicity against SW480 colon cancer cells, with MA-2 demonstrating a particularly strong effect. The half-maximal inhibition concentration (IC50) of the compounds was in the single-digit micromolar range, comparable to established SIRT inhibitors Selisistat and AGK2. Conclusion: The thiourea-based compounds synthesized in this study, especially MA-2, showed significant potential as SIRT inhibitors with cytotoxic activity against colon cancer cells. These results warrant further investigation into their therapeutic potential.

Anti-ovarian cancer migration and toxicity characteristics of a platinum(IV) pro-drug with axial HDAC inhibitor ligands in zebrafish models

SummaryOvarian cancer is the fifth leading cause of cancer related death in the United States. Cisplatin is a platinum-based anti-cancer drug used against ovarian cancer that enters malignant cells and then damages DNA causing cell death. Typically, ovarian cancer cells become resistant to cisplatin making it necessary to increase subsequent dosage, which usually leads to side-effects including irreversible damage to kidney and auditory system tissue. Ovarian cancer resistance is often associated with upregulation of histone deacetylase (HDAC) enzymes that cause DNA to adopt a closed configuration which reduces the ability of cisplatin to target and damage DNA. Compound B, a platinum(IV) complex with two axial phenylbutyrate (PBA) HDAC inhibitor ligands attached to a cisplatin core, can simultaneously inhibit HDAC activity and damage DNA causing decreased cancer cell viability in cisplatin-sensitive (A2780) and -resistant (A2780cis) ovarian cancer cell lines. However, compound B was not previously evaluated in vivo. As simultaneously inhibiting HDAC-mediated resistance with cisplatin treatment could potentiate the platinum drug’s effect, we first confirmed the anti-cancer effect of compound B in the A2780 and A2780cis cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide spectrophotometric assay. Then, we used zebrafish embryo and transgenic animal models to comparatively analyze the effect of cisplatin, compound B, and controls on general organismal, auditory, and renal system toxicity, and cancer metastasis. We found that lower dosages of compound B (0.3 or 0.6 µM) than of cisplatin (2.0 µM) could cause similar or decreased levels of general, auditory, and renal tissue toxicity, and at 0.6 µM, compound B reduces cancer metastasis more than 2.0 µM cisplatin.

Histone Deacetylases (HDACs) Roles in Inflammation-mediated Diseases; Current Knowledge.

The histone acetyl transferases (HATs) and histone deacetylases (HDACs), which are mostly recognized for their involvement in regulating chromatin remodeling via histone acetylation/deacetylation, have been shown to also change several non-histone proteins to regulate other cellular processes. Acetylation affects the activity or function of cytokine receptors, nuclear hormone receptors, intracellular signaling molecules, and transcription factors in connection to inflammation. Some small-molecule HDAC inhibitors are utilized as anticancer medications in clinical settings due to their capability to regulate cellular growth arrest, differentiation, and death. Here, we summarize our present knowledge of the innate and adaptive immunological pathways that classical HDAC enzymes control. The aim is to justify the targeted (or non-targeted) use of inhibitors against certain HDAC enzymes in inflammatory diseases such as arthritis, inflammatory bowel diseases (IBD), airways inflammation and neurological diseases.

The effect of favipiravir on histone deacetylase (HDAC) enzyme activity in administered to human primary chondrocyte cultures and an evaluation of its relationship with inflammation

The effect of favipiravir on histone deacetylase (HDAC) enzyme activity in administered to human primary chondrocyte cultures and an evaluation of its relationship with inflammation

Target and Gene-Based Therapeutic Strategies against Pancreatic Cancer: Current and Future Prospects.

Despite tremendous advancements in knowledge, diagnosis, and availability of both traditional and innovative treatments, pancreatic cancer remains a dangerous disease with a high death rate and dismal prognosis. The traditional strategy in adjuvant and palliative settings is still cytotoxic chemotherapy predicated on the purine derivative gemcitabine; nevertheless, there is an increasing need for new medicines that target the primary molecular pathways and pathophysiological abnormalities implicated. There is now just a tiny amount of evidence of therapeutic benefit when the targeted drug erlotinib is added to the conventional gemcitabine treatment. In preclinical and clinical trials, novel medications targeting mTOR, NF-κB, and proteasome, including the enzyme histone deacetylase, are currently being studied alongside the well-established monoclonal antibody treatments and small-molecule protein tyrosine kinase inhibitors. These novel medications may change the negative natural progression of this illness in conjunction with gene therapy and immunotherapy, both of which are undergoing clinical study. In this regard, leveraging miRNA manipulation to combat cancer is appealing due to its promise to deliver personalized treatment tailored to an individual's distinct gene or miRNA expression profile. Preclinical studies involving animals have showcased the effectiveness of miRNA-based therapies, with several of these treatments now progressing into human clinical trials for various malignancies and other medical conditions. This review describes the important developments of targeted therapeutics that are associated with pancreatic cancer and the discoveries which can help in dealing with this fatal malignancy in a more significant manner.

A novel inhibitor of class IIa histone deacetylases attenuates collagen-induced arthritis.

Most inhibitors of histone deacetylases (HDACs) are not selective and are cytotoxic. Some have anti-inflammatory activity in disease models, but cytotoxicity prevents long-term uses in non-fatal diseases. Inhibitors selective for class IIa HDACs are much less cytotoxic and may have applications in management of chronic inflammatory diseases. LL87 is a novel HDAC inhibitor examined here for HDAC enzyme selectivity. It was also investigated in macrophages for cytotoxicity and for inhibition of lipopolysaccharide (LPS)-stimulated cytokine secretion. In a rat model of collagen-induced arthritis, LL87 was investigated for effects on joint inflammation in Dark Agouti rats. Histological, immunohistochemical, micro-computed tomography and molecular analyses characterise developing arthritis and anti-inflammatory efficacy. LL87 was significantly more inhibitory against class IIa than class I or IIb HDAC enzymes. In macrophages, LL87 was not cytotoxic and reduced both LPS-induced secretion of pro-inflammatory cytokines, and IL6-induced class IIa HDAC activity. In rats, LL87 attenuated paw swelling and clinical signs of arthritis, reducing collagen loss and histological damage in ankle joints. LL87 decreased immune cell infiltration, especially pro-inflammatory macrophages and osteoclasts, into synovial joints and significantly reduced expression of pro-inflammatory cytokines and tissue-degrading proteases. A novel inhibitor of class IIa HDACs has been shown to have an anti-inflammatory and anti-arthritic profile distinct from current therapies. It is efficacious in reducing macrophage infiltration and joint inflammation in a chronic model of rat arthritis.

Hydrazides as Inhibitors of Histone Deacetylases.

In this Perspective, we have brought together available biological evidence on hydrazides as histone deacetylase inhibitors (HDACis) and as a distinct type of Zn-binding group (ZBG) to be reviewed for the first time in the literature. N-Alkyl hydrazides have transformed the field, providing innovative and practical chemical tools for selective and effective inhibition of specific histone deacetylase (HDAC) enzymes, in addition to the usual hydroxamic acid and o-aminoanilide ZBG-bearing HDACis. This has enabled efficient targeting of neurodegenerative diseases such as Alzheimer's disease, cancer, cardiovascular diseases, and protozoal pathologies.

In Silico Prediction of Binding Affinities of Hybrid Molecules of Benzothiazole Linked with Hydroxamic Acid by Disulfide Bond and Certain Linkers with HDAC8 Enzyme

A new hybrid molecule of Benzothiazole cross-linked with hydroxamic acid through an amino acid or aminoalkanoic acid were synthesised. All the synthesized hybrid molecules (1-5) were subjected to molecular docking studies to evaluate their binding affinities with histone deacetylase enzyme (HDAC8, PDB ID: 1T69) and recorded lower ΔG (-8.276, -10.093, -8.647, -6.315, -8.676 kcal/mole, respectively) than the reference ligand (Vorinostat, suberoylanilide hydroxamic acid, SAHA -5.375 kcal/mole). Molecular docking studies were performed using the maestro software (Schrödinger, version 2022-1). Moreover, compound 2, which is Benzothiazole-p-amino benzoic acid-hydroxamate has recorded the lowest binding score (-10.093). This may indicate that this compound is the most potent hybrid molecule. There were no violations from Lipinski’s rule and all the synthesized hybrid molecules comply with all parameters. Swiss ADME server was employed for the in silico molecular docking for prediction of the physicochemical and ADME properties of the investigated compounds. All hybrid molecules showed low possible passive oral absorption and no penetration into BBB. The hybrid molecules 1and 3 may be considered as P-gp substrates.

Exploring the anti-EBV potential of suberoylanilide hydroxamic acid: Induction of apoptosis in infected cells through suppressing BART gene expression and inducing lytic infection

Epstein-Barr virus (EBV) is linked to lymphoma and epithelioma but lacks drugs specifically targeting EBV-positive tumors. BamHI A Rightward Transcript (BART) miRNAs are expressed in all EBV-positive tumors, suppressing both lytic infection and host cell apoptosis. We identified suberoylanilide hydroxamic acid (SAHA), an inhibitor of histone deacetylase enzymes, as an agent that suppresses BART promoter activity and transcription of BART miRNAs. SAHA treatment demonstrated a more pronounced inhibition of cell proliferation in EBV-positive cells compared to EBV-negative cells, affecting both p53 wild-type and mutant gastric epithelial cells. SAHA treatment enhanced lytic infection in wild-type EBV-infected cells, while also enhancing cell death in BZLF1-deficient EBV-infected cells. It reduced BART gene expression by 85% and increased the expression of proapoptotic factors targeted by BART miRNAs. These findings suggest that SAHA not only induces lytic infection but also leads to cell death by suppressing BART miRNA transcription and promoting the apoptotic program.

Mocetinostat as a Novel Selective Histone Deacetylase Inhibitor in the Promotion of Apoptosis in glioblastoma Cell Line C6 and T98G

Abstract Background: Histone deacetylase (HDAC) enzymes play a crucial role in regulating gene expression and epigenetic alterations in cancer cells. Mocetinostat (MGCD0103) is a novel, isotype-selective HDAC inhibitor that targets Class I (HDAC1, 2, 3, and 8) and Class IV (HDAC11) enzymes. It has been approved for the use in phase II trials for Hodgkin’s lymphoma. Methods: In this study, the glioblastoma cell (GBM) lines T98G and C6 were treated with different concentrations of MGCD0103 (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 μM). Western blot analysis was used to evaluate protein expression and flow cytometry was employed to assess apoptosis. Results: The results demonstrated that MGCD0103 exerts multiple anti-cancer activities in GBMs. MGCD0103 modulated key signaling pathways, including inhibition of the Phosphatidylinositol 3- kinase (PI3K)/protein kinase B mechanism pathway and suppression of HDAC1 enzyme activity. High doses of MGCD0103 significantly induced apoptosis and suppressed cell proliferation by upregulating the pro-apoptotic protein Bcl-2-associated protein x and downregulating the anti-apoptotic proteins BH3 Interacting Domain Death Agonist and B-cell leukemia/lymphoma 2 protein. In addition, MGCD0103 treatment upregulated the expression of the tumor-suppressor gene and downregulated the E2F1 transcription factor. Furthermore, MGCD0103 facilitated cell differentiation by activating the glial fibrillary acidic protein Glial Fibrillary acidic protein (GFAP) as distinguish marker of astrocytes, and suppressing the undifferentiation markers Inhibitor of Deoxyribonucleic acid binding 2 and N-Myc proto-oncogene protein. Conclusion: This research suggests that MGCD0103 is a promising drug for inhibiting the proliferation, invasion, and migration of GBMs. The findings also provide new insights into the ability of MGCD0103 to induce differentiation in GBMs. Overall, these results indicate that MGCD0103 could be a potent therapeutic agent for the target of glioblastoma.

Molecular docking of curcumin and curcuminoids as human Zn+ dependent histone deacetylase (HDAC) enzyme inhibitors.

The online version contains supplementary material available at 10.1007/s40203-024-00221-4.

Sulfur(VI) Fluoride Exchange Chemistry in Solid-Phase Synthesis of Compound Arrays: Discovery of Histone Deacetylase Inhibitors.

Multistep synthesis performed on solid support is a powerful means to generate small-molecule libraries for the discovery of chemical probes to dissect biological mechanisms as well as for drug discovery. Therefore, expansion of the collection of robust chemical transformations amenable to solid-phase synthesis is desirable for achieving chemically diverse libraries for biological testing. Here, we show that sulfur(VI) fluoride exchange (SuFEx) chemistry, exemplified by pairing phenols with aryl fluorosulfates, can be used for the solid-phase synthesis of biologically active compounds. As a case study, we designed and synthesized a library of 84 hydroxamic acid-containing small molecules, providing a rich source of inhibitors with diverse selectivity profiles across the human histone deacetylase enzyme family. Among other discoveries, we identified a scaffold that furnished inhibitors of HDAC11 with exquisite selectivity in vitro and a selective inhibitor of HDAC6 that was shown to affect the acetylation of α-tubulin over histone sites H3K18, H3K27, as well as SMC3 in cultured cells. Our results encourage the further use of SuFEx chemistry for the synthesis of diverse small-molecule libraries and provide insight for future design of selective HDAC inhibitors.