Search

The clinical use of many potent anticancer agents is limited by their non-selective toxicity to healthy tissue. One of these examples is vorinostat (SAHA), a pan histone deacetylase inhibitor, which shows high cytotoxicity with limited discrimination for cancerous over healthy cells. In an attempt to improve tumor selectivity, we exploited the properties of cobalt(III) as a redox-active metal center through stabilization with cyclen and cyclam tetraazamacrocycles, masking the anticancer activity of SAHA and other hydroxamic acid derivatives to allow for the complex to reach the hypoxic microenvironment of the tumor. Biological assays demonstrated the desired low in vitro anticancer activity of the complexes, suggesting effective masking of the activity of SAHA. Once in the tumor, the bioactive moiety may be released through the reduction of the Co III center. Investigations revealed long-term stability of the complexes, with cyclic voltammetry and chemical reduction experiments supporting the design hypothesis of SAHA release through the reduction of the Co III prodrug. The results highlight the potential for further developing this complex class as novel anticancer agents by masking the high cytotoxicity of a given drug, however, the cellular uptake needs to be improved., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Histonedeacetylase inhibitor (HDACi) has great potential in targeted antitumor therapy by inhibiting tumor migration, invasion, and metastasis. As one of the typical HDACis, vorinostat (Suberoylanilide Hydroxamic Acid, SAHA) was approved as a therapeutic agent for cancer therapy, however, challenges remain due to their poor solubility, short half-life and low efficiency in cellular penetration. Considering the disadvantages of usual drug carriers, folate and vorinostat bound BSA nanogel (FVBN)was fabricated to implement higher solubility, stability, cellular uptake, and lipase-responsive release. With good dispersion and stability, FVBN significantly increased the cellular uptake of vorinostat through folate-mediated endocytosis. FVBN exhibited comparable cytotoxicity with free SAHA, and the growth of tumor cells was blocked in G1/G0 phase just like SAHA performed in cell cycle arrest tests. Moreover, FVBN not only effectively inhibited the growth of melanoma but also observably prevented pulmonary metastasis of melanoma. In the experiment against nude mice bearing solid ovarian cancer, FVBN showed excellent antitumor effect without liver damage, demonstrating the superiority of gelated and inner-lysosome triggered release strategies to the free SAHA, and it is promising to expand the scope of application of HDACi in clinical cancer therapy., Competing Interests: Declaration of Competing Interest The authors report no conflicts of interest in this work., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Radiotherapy (RT) is one of the most extensive and effective approaches available for clinical tumor treatment. However, tumor microenvironments including hypoxia and histone deacetylase (HDAC) overexpression could induce radiation resistance, leading to tumor recurrence. Herein, nanoparticles (CAT-SAHA@PLGA) encapsulating catalase and HDAC inhibitor SAHA exhibited protected catalytic activity of catalase and prolonged the pharmacokinetic exposure of the HDAC inhibitor. Overall, the established CAT-SAHA@PLGA nanoparticles could overcome radiation resistance by synergistically increasing tumor oxygenation and inhibiting HDAC activity.

Vorinostat (suberoylanilide hydroxamic acid; SAHA) and Belinostat are two hydroxamate-based histone deacetylase inhibitors that are used clinically as potent anti-cancer agents. Their metabolic breakdown into inactive metabolites such as carboxylic acid and glucuronic derivatives results in them having short half-lives, which can negatively impact their pharmacokinetic profiles. Herein we report the potential of both Vorinostat and Belinostat to also act as nitric oxide donors under both chemical and biological ex vivo experimental conditions. More specifically, using ruthenium(III) as an effective NO scavenger, we were able to establish, in the first instance, that both Vorinostat and Belinostat had the capacity to release NO under chemical conditions. Both Vorinostat and Belinostat were then shown to cause vascular relaxation of rat aorta via NO-mediated activation of the haem-containing guanylate cyclase enzyme. A summary of our findings is reported herein., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Four compounds T1, T2, T3, and T4 were designed and synthesized as Vorinostat and Belinostat derivatives being the target water-soluble prodrugs. The water solubility of Vorinostat derivatives, T1 and T2, exhibited 400- to 600-fold higher than that of Vorinostat, and Belinostat derivatives, T3 and T4, showed 600- to 750-fold higher than that of Belinostat. Four compounds were evaluated for their inhibitory activities against tumor cell lines HT-29 and Hut-78 in the absence or presence of β-D-glucuronidase. The inhibitory effects of T1 and T2 were comparable to Vorinostat in the presence of β-D-glucuronidase, but were higher than 10 μM in the absence of β-D-glucuronidase. Therefore, T1 and T2 are promising candidates for in vivo investigations with high potential to be the target water-soluble prodrugs. IC 50 values of Belinostat derivatives T3 and T4 were not affected by β-D-glucuronidase, but T3 and T4 had the excellent cell proliferation inhibition on Hut-78., (© 2019 John Wiley & Sons A/S.)

In the present study, we investigated the p53-independent mechanism by which quercetin (Q) increased apoptosis in human lung cancer H1299 cells exposed to trichostatin A (TSA), a histone deacetylase inhibitor. We also investigated the role of Q in increasing the acetylation of histones H3 and H4 and the possible mechanism. Q at 5 μM significantly increased apoptosis by 88% in H1299 cells induced by TSA at 72 h. Q also significantly increased TSA-induced death receptor 5 (DR5) mRNA and protein expression as well as caspase-10/3 activities in H1299 cells. Transfection of DR5 siRNA into H1299 cells significantly diminished the enhancing effects of Q on TSA-induced apoptosis. Furthermore, TSA in combination with Q rather than TSA alone significantly increased p300 expression. Transfection of p300 siRNA in H1299 cells significantly diminished the increase of histone H3/H4 acetylation, DR5 protein expression, caspase-10/3 activity and apoptosis induced by Q. In addition, similar effects of Q were observed when Q was combined with vorinostat, another FDA-approved histone deacetylase inhibitor. These data suggest that the up-regulation of p300 expression, which in turn increases histone acetylation and DR5 expression, plays an important role in the enhancing effect of Q on TSA/vorinostat- induced apoptosis in H1299 cells., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Specifically blocking more than one oncogenic pathway simultaneously in a cancer cell with a combination of different drugs is the mainstay of the majority of cancer treatments. Being able to do this via two targeted pathways without inducing side effects through a general mechanism, such as chemotherapy, could bring benefit to patients. In this work we describe a new dual inhibitor of the JAK-STAT and HDAC pathways through designing and developing two types of molecule based on the JAK2 selective inhibitor XL019 and the pan-HDAC inhibitor, vorinostat. Both series of compounds had examples with low nanomolar JAK2 and HDAC1/6 inhibition. In some cases good HDAC1 selectivity was achieved while retaining HDAC6 activity. The observed potency is explained through molecular docking studies of all three enzymes. One example, 69c had 16-25 fold selectivity against the three other JAK-family proteins JAK1, JAK3 and TYK2. A number of compounds had sub-micromolar potencies against a panel of 4 solid tumor cell lines and 4 hematological cell lines with the most potent compound, 45h, having a cellular IC 50 of 70 nM against the multiple myeloma cell line KMS-12-BM. Evidence of both JAK and HDAC pathway inhibition is presented in Hela cells showing that both pathways are modulated. Evidence of apoptosis with two compounds in 4 sold tumor cell lines is also presented., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Vorinostat (VOR), a potent HDAC inhibitor, suffers from low solubility and poor absorption, which hinders its successful application in therapy, especially in the treatment of solid tumors. In this study, an effort to improve the physicochemical characteristics of VOR was made by encapsulating it in PEG-PLGA copolymeric micelles. VOR-loaded PEG-PLGA micelles (VOR-PEG-PLGA) were produced by thin-film hydration and physicochemically characterized. The PEG-PLGA micelles had an average size of 124.06 ± 2.6 nm, polydispersity index of 0.27 ± 0.1, and entrapment efficiency of 90 ± 2.1%. Micelles were characterized by TEM, DSC, and drug release studies. The drug release occurred in a sustained manner up to 72 h from PEG-PLGA micelles. In the in vitro cell-based studies using human breast cancer (MDA MB 231) and murine melanoma (B16F10) cell lines, VOR-PEG-PLGA micelles exhibited superior cellular internalization, enhanced cytotoxic activity, and greater apoptosis compared to free drug. Percent cell killing of 54.9% for VOR-PEG-PLGA-treated cells was observed after 24 h compared to 36% for free VOR in MDA MB 231 cell line. Further, significant tumor suppression was witnessed in B16F10 tumor-bearing mice treated with VOR-PEG-PLGA micelles with a 1.78-fold reduction in tumor volume compared to free VOR-treated animals. Overall, the VOR-PEG-PLGA micelles improved the biopharmaceutical properties of VOR, which resulted in enhanced anti-tumor efficacy. Therefore, the newly developed nano-formulation of VOR could be considered as an effective treatment option in solid tumors.

This study was conducted to investigate whether the treatment of dog to pig interspecies somatic cell nuclear transfer (iSCNT) embryos with a histone deacetylase inhibitor, to improve nuclear reprogramming, can be applied to dog SCNT embryos. The dog to pig iSCNT embryos were cultured in fresh porcine zygote medium-5 (PZM-5) with 0, 1, or 10 µM suberoylanilide hydroxamic acid (SAHA) for 6 h, then transferred to PZM-5 without SAHA. Although there were no significant differences in cleavage rates, the rates of 5-8-cell stage embryo development were significantly higher in the 10 µM group (19.5 ± 0.8%) compared to the 0 µM groups (13.4 ± 0.8%). Acetylation of H3K9 was also significantly higher in embryos beyond the 4-cell stage in the 10 µM group compared to the 0 or 1 µM groups. Treatment with 10 µM SAHA for 6 h was chosen for application to dog SCNT. Dog cloned embryos with 0 or 10 µM SAHA were transferred to recipients. However, there were no significant differences in pregnancy and delivery rates between the two groups. Therefore, it can be concluded that although porcine oocytes support nuclear reprogramming of dog fibroblasts, treatment with a histone deacetylase inhibitor that supports nuclear reprogramming in dog to pig iSCNT embryos was not sufficient for reprogramming in dog SCNT embryos.

Glioblastoma multiforme (GBM), often referred to as a grade IV astrocytoma, is the most invasive type of tumor arising from glial cells. The main treatment options for GBM include surgery, radiation and chemotherapy. However, these treatments tend to be only palliative rather than curative. Poor prognosis of GBM is due to its marked resistance to standard therapy. Currently, temozolomide (TMZ), an alkylating agent is used for treatment of GBM. However, GBM cells can repair TMZ‑induced DNA damage and therefore diminish the therapeutic efficacy of TMZ. The potential to evade apoptosis by GBM cells accentuates the need to target the non‑apoptotic pathway and/or inhibition of pro‑survival strategies that contribute to its high resistance to conventional therapies. In recent studies, it has been demonstrated that HDAC inhibitors, such as vorinostat (suberoyl anilide hydroxamic acid; SAHA) can induce autophagy in cancer cells, thereby stimulating autophagosome formation. In addition, a lysosomotropic agent such as chloroquine (CQ) can result in hyper‑accumulation of autophagic vacuoles by inhibiting autophagosome‑lysosome fusion, which can drive the cell towards apoptosis. Hence, we postulated that combination treatment with SAHA and CQ may lead to increased formation of autophagosomes, resulting in its hyper‑accumulation and ultimately inducing cell death in GBM cells. In the present study, we demonstrated that CQ co‑treatment enhanced SAHA‑mediated GBM cell apoptosis. Inhibition of the early stage of autophagy by 3‑methyladenine pre‑treatment reduced cell death confirming that apoptosis induced by CQ and SAHA was dependent on autophagosome accumulation. We also demonstrated that autophagy inhibition led to enhanced ROS, mitochondria accumulation and reduced mitochondrial membrane potential resulting in cell death. The present study provides cellular and molecular evidence concerning the combined effect of SAHA and CQ which can be developed as a therapeutic strategy for the treatment of glioblastoma in the future.

Objectives: Histone deacetylases (HDACs) are commonly dysregulated in cancer and represent promising therapeutic targets. However, global HDAC inhibitors have shown limited efficacy in the treatment of solid tumours, including hepatocellular carcinoma (HCC). In this study, we investigated the therapeutic effect of selectively inhibiting HDAC1 and 2 in HCC., Methods: HDAC1 inhibitor Tacedinaline (CI994), HDAC2 inhibitor Santacruzamate A (CAY10683), HDAC1/2 common inhibitor Romidepsin (FK228) and global HDAC inhibitor Vorinostat (SAHA) were used to treat HCC cells. Cell cycle, apoptosis and the protein levels of CDKs and CDKNs were performed to evaluate HCC cell growth. Inhibition of HDAC1/2 by RNAi was further investigated., Results: Combined inhibition of HDAC1/2 led to HCC cell morphology changes, growth inhibition, cell cycle blockage and apoptosis in vitro and suppressed the growth of subcutaneous HCC xenograft tumours in vivo. p21 Waf1/Cip1 and p19 INK 4d , which play roles in cell cycle blockage and apoptosis induction, were upregulated. Inhibition of HDAC1/2 by siRNA further demonstrated that HDAC1 and 2 cooperate in blocking the cell cycle and inducing apoptosis via p19 INK 4d and p21 Waf1/Cip1 upregulation. Finally, H3K18, H3K56 and H4K12 in the p19 INK 4d and p21 Waf1/Cip1 promoter regions were found to be targets of HDAC1/2., Conclusions: Pharmacological or transcriptional inhibition of HDAC1/2 increases p19 INK 4d and p21 Waf1/Cip1 expression, decreases CDK expression and arrests HCC growth. These results indicated a potential pharmacological mechanism of selective HDAC1/2 inhibitors in HCC therapy., (© 2018 John Wiley & Sons Ltd.)

Aim: Acetylation levels of histones are the result of the balance between histone acetyltransfrases and histone deacetylases activities, which plays an important role in chromatin remodeling and regulation of gene expression. Histone deacetylases inhibitors such as valproic acid, vorinostat have attracted interest because of their ability to induce differentiation and apoptosis of cancer cells. The current study was designed to assess the effect of valproic acid in comparison to and in combination with vorinostat on cell growth inhibition and apoptosis induction in the human colon cancer SW48 cells., Materials and Methods: The colon cancer SW48 cells were seeded and treated with various doses of valproic acid and vorinostat and MTT assay and flow cytometric assay were done to determine cell viability and cell apoptosis, respectively., Results: All concentrations of both agents reduced viability significantly in a dose- and time-dependent fashion (p < 0.004). Both compounds, either single or combined agents, induced apoptosis significantly, whereas the ratio of the apoptotic cells treated with combined agents was more significant than the single., Conclusion: Our findings suggest that vaproic acid and vorinostat can significantly inhibit cell growth and induce apoptosis in colon cancer SW48 cells.

Major depressive disorder (MDD) is a multifactorial neuropsychiatric disorder. Chronic administration of corticosterone (CORT) to rodents is used to mimic the stress associated dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, a well-established feature found in depressive patients. Recently, preclinical studies have demonstrated the antidepressant potential of histone deacetylase (HDAC) inhibitors. So, we examined the antidepressant potential of vorinostat (VOR), a HDAC inhibitor against CORT injections in male mice. VOR (25 mg/kg; intraperitoneal) and fluoxetine (FLX) (15 mg/kg; oral) treatments were provided to CORT administered mice. At the end of dosing schedule, neurobehavioral tests were conducted; followed by mechanistic evaluation through biochemical analysis, RTPCR and western blot in serum and hippocampus. Neurobehavioral tests revealed the development of anxiety/depressive-like behavior in CORT mice as compared to the vehicle control. Depressive-mice showed concomitant HPA axis dysregulation as observed from the significant increase in serum CORT and ACTH. Chronic CORT administration was found to significantly increase hippocampal malondialdehyde (MDA) and iNOS levels while lowering glutathione (GSH) content, as compared to vehicle control. VOR treatment, in a similar manner to the classical antidepressant FLX, significantly ameliorated anxiety/depressive-like behavior along with HPA axis alterations induced by CORT. The antidepressant-like ability of drug treatments against chronic CORT induced stress model, as revealed in our study, may be due to their potential to mitigate inflammatory damage and oxidative stress via modulation of hippocampal NF-κB p65, COX-2, HDAC2 and phosphorylated JNK levels., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Hypoxia promotes HCC progression and therapy resistance, and there is no systemic treatment for HCC patients after sorafenib resistance. Thus, it is urgent to develop potential therapeutic regimens for HCC patients by targeting hypoxia signaling. In this study, we showed that evodiamine might be a potential therapeutic medicine for HCC by suppressing HIF-1α. In addition, evodiamine could sensitize the anti-HCC effect of vorinostat in HCC cells under hypoxia. Furthermore, evodiamine plus vorinostat accelerated the degradation of HIF-1α in HCC cells under hypoxia. In general, evodiamine might be a potential therapeutic candidate for HCC patients, and evodiamine combining with vorinostat might be an attractive chemotherapy strategy for HCC treatment., (Copyright © 2018 Elsevier Inc. All rights reserved.)

A 70-year-old man presented to our clinic with a 10-year history of recurrent pruritic erythema and plaques on his trunk and limbs. Based on the pathological findings and monoclonal rearrangement of the T-cell receptor (TCR)-Cβ1 gene, mycosis fungoides (T2N0M0B0 stage IB) was diagnosed. Despite combination therapy including histone deacetylase inhibitor (vorinostat), the symptoms slowly evolved into Sézary syndrome (SS; T4N1M0B2) over 4 years, with dense infiltrates due to atypical lymphocytes expressing CCR4 developing in the entire dermis. Anti-CCR4 monoclonal antibody (mogamulizumab) treatment was started. After seven courses, the CCR4-positive atypical lymphocytes decreased in the dermis to levels below those seen at the outset of treatment. To our knowledge, there is no previous report of a case of SS managed with vorinostat followed by mogamulizumab demonstrating such a remarkable change in the pathological state following treatment., (© 2018 British Association of Dermatologists.)

Background: New tuberculosis (TB) drug treatment regimens are urgently needed. This study evaluated the potential of the histone deacetylase inhibitors (HDIs) valproic acid (VPA) and suberoylanilide hydroxamic acid (SAHA) to enhance the effects of first-line anti-TB drugs against intracellular Mycobacterium tuberculosis., Methods: M. tuberculosis H37Rv cultures were exposed to VPA or SAHA over 6 days, in the presence or absence of isoniazid (INH) and rifampicin (RIF). The efficacy of VPA and SAHA against intracellular M. tuberculosis with and without INH or RIF was tested by treating infected macrophages. Bactericidal activity was assessed by counting mycobacterial colony-forming units (CFU)., Results: VPA treatment exhibited superior bactericidal activity to SAHA (2-log CFU reduction), while both HDIs moderately improved the activity of RIF against extracellular M. tuberculosis. The bactericidal effect of VPA against intracellular M. tuberculosis was greater than that of SAHA (1-log CFU reduction) and equalled that of INH (1.5-log CFU reduction). INH/RIF and VPA/SAHA combination treatment inhibited intracellular M. tuberculosis survival in a shorter time span than monotherapy (3days vs. 6 days)., Conclusions: VPA and SAHA have adjunctive potential to World Health Organization-recommended TB treatment regimens. Clinical evaluation of the two drugs with regard to reducing the treatment duration and improving treatment outcomes in TB is warranted., (Copyright © 2018. Published by Elsevier Ltd.)

Histone acetylation is one of the most abundant post-translational modifications in eukaryotic cells; aberrant histone acetylation is related to a range of cancer types because of the dysregulation of histone deacetylases (HDACs). Inhibition of HDACs leads to suppression of tumor growth in multiple cancers, whereas the inhibitory effects of HDAC inhibitors remain incompletely understood in epidermal growth factor receptor (EGFR)-mutant lung cancers. In this study, the antitumor effects of HDACs inhibitor suberoylanilide hydroxamic acid (SAHA, vorinostat) were examined in EGFR-mutant lung cancer cell lines. The results of the present work showed that SAHA markedly inhibited cell viability and proliferation, induced cell apoptosis by arresting the cell cycle in the G2/M phase, and significantly reduced tumor growth in a xenograft model. Further study confirmed that the suppression function of SAHA might be mediated by regulating the ERK-dependent and/or the AKT-dependent pathway; meanwhile, angiogenesis abrogation induced by SAHA exerted effects on tumor regression in vivo. Taken together, our results identify the antitumor effects of HDACs inhibitor SAHA as an alternative therapeutic application for the epigenetic treatment of EGFR-mutant non-small-cell lung cancer.

Suberoylanilide hydroxamic acid (SAHA) is a histone deacetylase inhibitor, which has been widely utilized throughout the cancer research field. SAHA-induced radiosensitization in normal human fibroblasts AG1522 and lung carcinoma cells A549 were evaluated with a combination of γ-rays, proton, and carbon ion exposure. Growth delay was observed in both cell lines during SAHA treatment; 2 μM SAHA treatment decreased clonogenicity and induced cell cycle block in G1 phase but 0.2 μM SAHA treatment did not show either of them. Low LET (Linear Energy Transfer) irradiated A549 cells showed radiosensitization effects on cell killing in cycling and G1 phase with 0.2 or 2 μM SAHA pretreatment. In contrast, minimal sensitization was observed in normal human cells after low and high LET radiation exposure. The potentially lethal damage repair was not affected by SAHA treatment. SAHA treatment reduced the rate of γ-H2AX foci disappearance and suppressed RAD51 and RPA (Replication Protein A) focus formation. Suppression of DNA double strand break repair by SAHA did not result in the differences of SAHA-induced radiosensitization between human cancer cells and normal cells. In conclusion, our results suggest SAHA treatment will sensitize cancer cells to low and high LET radiation with minimum effects to normal cells., Competing Interests: The authors declare no conflict of interest.

We designed and synthesized carbamates of the clinically-approved HDAC (histone deacetylase) inhibitor vorinostat (suberoylanilide hydroxamic acid, SAHA) in order to validate our previously-proposed hypothesis that these carbamates might serve as prodrugs for hydroxamic acid containing HDAC inhibitors. Biochemical assays proved our new compounds to be potent inhibitors of histone deacetylases in vitro, and they also showed antiproliferative effects in leukemic cells. These results, as well as stability analysis led to the suggestion that the intact carbamates are inhibitors of histone deacetylases themselves, representing a new zinc-binding warhead in HDAC inhibitor design. This suggestion was further supported by the synthesis and evaluation of a carbamate derivative of the HDAC6-selective inhibitor bufexamac., Competing Interests: The authors declare no conflict of interest.

Hierarchical leaf-like gold nanolayers were electrodeposited using choline chloride as a shape directing agent and characterized using field emission scanning electron microscopy. The electrooxidation behavior of vorinostat was then studied on the nanolayers and the kinetic parameters of the electrodic process were obtained by voltammetric measurements in a phosphate buffer solution at pH 7.40. Vorinostat was electrooxidized on the nanolayers' surface at a lower potential and with a higher rate, compared to a polycrystalline smooth gold surface, through an irreversible process. Based on the results, an amperometric sensor was designed using the hierarchical leaf-like gold nanolayers for the determination of vorinostat. A linear dynamic range of 4.0-52μmol L -1 with a calibration sensitivity of 7.7mAmol -1 L, and a detection limit of 1.40μmolL -1 were obtained. The amperometry method was also applied to the analysis of vorinostat capsules., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Treatment regimens for cancer patients using single chemotherapeutic agents often lead to undesirable toxicity, drug resistance, reduced uptake etc. Combination of two or more drugs is therefore becoming an imperative strategy to overcome these limitations. A step forward can be taken through delivery of the drugs used in combination via nanoparticles. Co-administration of chemotherapeutic drugs encapsulated in nanoparticles has been shown to result in synergistic effects and enhanced therapeutic efficacy. In present study, we explored the combination treatment of histone deacetylase inhibitor vorinostat (VOR) and topoisomerase II inhibitor etoposide (ETOP). The concurrent combination treatment of VOR and ETOP resulted in synergistic effect on human cervical HeLa cancer cells. VOR and ETOP were encapsulated into poly(ethylene glycol) monomethacrylate (POEOMA)-based disulfide cross-linked nanogels. The nanogels were synthesized using atom transfer radical polymerization (ATRP) via cyclohexane/water inverse mini-emulsion and were degradable in presence of intracellular glutathione (GSH) concentration. Both the drugs were loaded into the nanogels by physical encapsulation method and characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and differential scanning calorimetry (DSC). Both VOR- and ETOP-loaded nanogels showed sustained release profile. Furthermore, combination treatment drugs encapsulated of POEOMA nanogel demonstrated enhanced synergistic cytotoxic effect compared with combination of free drugs. Enhanced synergistic cell killing efficiency of drug-loaded POEOMA nanogels was due to increased apoptosis via caspase 3/7 activation. Therefore, combination of VOR- and ETOP-loaded PEG-based biodegradable nanogels may provide a promising therapy with enhanced anticancer effect.

SERCA2a is the Ca 2+ ATPase playing the major contribution in cardiomyocyte (CM) calcium removal. Its activity can be regulated by both modulatory proteins and several post-translational modifications. The aim of the present work was to investigate whether the function of SERCA2 can be modulated by treating CMs with the histone deacetylase (HDAC) inhibitor suberanilohydroxamic acid (SAHA). The incubation with SAHA (2.5 µM, 90 min) of CMs isolated from rat adult hearts resulted in an increase of SERCA2 acetylation level and improved ATPase activity. This was associated with a significant improvement of calcium transient recovery time and cell contractility. Previous reports have identified K464 as an acetylation site in human SERCA2. Mutants were generated where K464 was substituted with glutamine (Q) or arginine (R), mimicking constitutive acetylation or deacetylation, respectively. The K464Q mutation ameliorated ATPase activity and calcium transient recovery time, thus indicating that constitutive K464 acetylation has a positive impact on human SERCA2a (hSERCA2a) function. In conclusion, SAHA induced deacetylation inhibition had a positive impact on CM calcium handling, that, at least in part, was due to improved SERCA2 activity. This observation can provide the basis for the development of novel pharmacological approaches to ameliorate SERCA2 efficiency., Competing Interests: The authors declare no conflict of interest.

Despite increasing advances in the diagnosis and treatment for pancreatic cancer, the mortality rate remains high world-wide. There is an urgent need for new therapies to improve survival and quality of life for pancreatic cancer patient. Epigenetic therapeutic agents such as 5-Aza‑CdR and suberoylanilide hydroxamic acid (SAHA) have shown therapeutic effects for human cancers. We evaluated the efficacy of 5-Aza‑CdR or SAHA and their combination as potential therapies for pancreatic cancer in vitro. Treatment with 5-Aza‑CdR or SAHA inhibited pancreatic cancer cell proliferation, migration and induced cell arrest. However, 5-Aza‑CdR alone can not induce cell apoptosis. Combination of the two agents enhanced the proliferation and migration inhibition, and induced more cells to G2 arrest and increased the cell apoptosis proportion. Furthermore, combination treatment with SAHA and 5-Aza‑CdR significantly increased expression of TP53 and P16. The possible mechanism might be that the two agents inhibited the PI3K/AKT/PTEN signaling pathway. In conclusion, these data demonstrate a potential role for epigenetic modifier drugs for the management of pancreatic cancer.

Histone deacetylase (HDAC) enzymes govern the post-translational acetylation state of lysine residues on protein substrates, leading to regulatory changes in cell function. Due to their role in cancers, HDAC proteins have emerged as promising targets for cancer treatment. Four HDAC inhibitors have been approved as anti-cancer therapeutics, including SAHA (Suberoylanilide hydroxamic acid, Vorinostat, Zolinza). SAHA is a nonselective HDAC inhibitor that targets most of the eleven HDAC isoforms. The nonselectivity of SAHA might account for its clinical side effects, but certainly limits its use as a chemical tool to study cancer-related HDAC cell biology. Herein, the nonselective HDAC inhibitor SAHA was modified at the C4 position of the linker to explore activity and selectivity. Several C4-modified SAHA analogs exhibited dual HDAC6/8 selectivity. Interestingly, (R)-C4-benzyl SAHA displayed 520- to 1300-fold selectivity for HDAC6 and HDAC8 over HDAC1, 2, and 3, with IC 50 values of 48 and 27 nM with HDAC6 and 8, respectively. In cellulo testing of the inhibitors was consistent with the observed in vitro selectivity. Docking studies provided a structural rationale for selectivity. The C4-SAHA analogs represent useful chemical tools to understand the role of HDAC6 and HDAC8 in cancer biology and exciting lead compounds for targeting of both HDAC6 and HDAC8 in various cancers., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Background: Methylated gene markers have shown promise in predicting breast cancer outcomes and treatment response. We evaluated whether baseline and changes in tissue and serum methylation levels would predict pathological complete response (pCR) in patients with HER2-negative early breast cancer undergoing preoperative chemotherapy., Methods: The TBCRC008 trial investigated pCR following 12 weeks of preoperative carboplatin and albumin-bound paclitaxel + vorinostat/placebo (n = 62). We measured methylation of a 10-gene panel by quantitative multiplex methylation-specific polymerase chain reaction and expressed results as cumulative methylation index (CMI). We evaluated association between CMI level [baseline, day 15 (D15), and change] and pCR using univariate and multivariable logistic regression models controlling for treatment and hormone receptor (HR) status, and performed exploratory subgroup analyses., Results: In univariate analysis, one log unit increase in tissue CMI levels at D15 was associated with 40% lower chance of obtaining pCR (odds ratio, OR 0.60, 95% CI 0.37-0.97; p = 0.037). Subgroup analyses suggested a significant association between tissue D15 CMI levels and pCR in vorinostat-treated [OR 0.44 (0.20, 0.93), p = 0.03], but not placebo-treated patients., Conclusion: In this study investigating the predictive roles of tissue and serum CMI levels in patients with early breast cancer for the first time, we demonstrate that high D15 tissue CMI levels may predict poor response. Larger studies and improved analytical procedures to detect methylated gene markers in early stage breast cancer are needed. TBCRC008 is registered on ClinicalTrials.gov (NCT00616967).

Purpose: To translate promising preclinical data on the combination of vorinostat and ixabepilone for metastatic breast cancer (MBC) into clinical trials., Methods: We conducted a randomized two-arm Phase IB clinical trial of ascending doses of vorinostat and ixabepilone in prior -treated MBC patients. To determine the maximum tolerated dose (MTD), 37 patients were randomized to schedule A: every-3-week ixabepilone + vorinostat (days 1-14), or schedule B: weekly ixabepilone + vorinostat (days 1-7; 15-21) Pharmacokinetics were assessed. Nineteen additional patients were randomized to schedule A or B and objective response rate (ORR), clinical benefit rate (CBR), toxicity, progression-free survival (PFS), and overall survival (OS) were assessed., Results: The schedule A MTD was vorinostat 300 mg daily (days 1-14), ixabepilone 32 mg/m 2 (day 2); 21-day cycle 27% dose-limiting toxicities (DLTs). The schedule B MTD was vorinostat 300 mg daily (days 1-7; 15-21), ixabepilone 16 mg/m 2 (days 2, 9, 16); 28-day cycle; no DLTs. Vorinostat and ixabepilone clearances were 194 L/h and 21.3 L/h/m 2 , respectively. Grade 3 peripheral sensory neuropathy was reported in 8% (A) and 21% (B) of patients. The ORR and CBR were 22 and 22% (A); 30 and 35% (B). Median PFS was 3.9 (A) and 3.7 (B) months. OS was 14.8 (A) and 17.1 (B) months., Conclusions: We established the MTD of vorinostat and ixabepilone. This drug combination offers a novel therapy for previously treated MBC patients. The potential for lower toxicity and comparable efficacy compared to current therapies warrants further study.

SAHA, a member of histone deacetylase inhibitors (HDACIs), which emerged as a class of novel antitumor drug, has been used in clinical treatment of cancers. However, clinical experience of SAHA in solid tumors has been disappointing. Nevertheless, the underlying mechanism of this deficiency is not clearly understood. In the present study, we found that SAHA could induce epithelial-mesenchymal transitions (EMT) in lung cancer A549 cells, which was associated with increased migration capability and cellular morphology changes. We showed that SAHA decreased epithelial marker E-cadherin's expression and increased the expression of mesenchymal marker vimentin. SAHA upregulated the protein and mRNA expression of transcription factor Slug in a time-dependent manner and promoted its nuclear translocation. We further demonstrated that SAHA upregulated Slug expression by promoting Slug acetylation but not influencing the phosphorylation of GSK-3β, a main kinase-controlled Slug expression. Finally, silencing of Slug by siRNA reversed EMT marker expressions and cellular morphology change induced by SAHA, suggesting that Slug plays a crucial role in SAHA-mediated EMT in A549 cells. Our research study provided a better understanding of treatment failure of SAHA in patients with solid tumors. Therefore, more attention should be paid to cancer treatment using SAHA and strategies for reversing EMT before using SAHA would be better if the value of SAHA in the treatment of solid tumors, especially lung cancer, is realized.

Jay Amin hydroxamic acid (JAHA; N8-ferrocenylN 1 -hydroxy-octanediamide) is a ferrocene-containing analogue of the histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA). JAHA's cytotoxic activity on MDA-MB231 triple negative breast cancer (TNBC) cells at 72 h has been previously demonstrated with an IC 50 of 8.45 μM. JAHA's lethal effect was found linked to perturbations of cell cycle, mitochondrial activity, signal transduction, and autophagy mechanisms. To glean novel insights on how MDA-MB231 breast cancer cells respond to the cytotoxic effect induced by JAHA, and to compare the biological effect with the related compound SAHA, we have employed a combination of differential display-PCR, proteome analysis, and COMET assay techniques and shown some differences in the molecular signature profiles induced by exposure to either HDACis. In particular, in contrast to the more numerous and diversified changes induced by SAHA, JAHA has shown a more selective impact on expression of molecular signatures involved in antioxidant activity and DNA repair. Besides expanding the biological knowledge of the effect exerted by the modifications in compound structures on cell phenotype, the molecular elements put in evidence in our study may provide promising targets for therapeutic interventions on TNBCs.

Metastatic cancer is regarded as one of the largest contributors to disease-related deaths worldwide. Poor patient prognosis and treatment outcome is tied to the lack of efficacious anti-cancer therapies, which is due in part to the lack of physiologically relevant in vitro screening systems that can mimic the native tumor microenvironment. Conventional drug-screening platforms, which are often used in the pharmaceutical industry, are either two-dimensional (2D) assays or three-dimensional (3D) hydrogel-based matrices that lack precise control over cell distribution, matrix architecture, and organization. Despite the significance of in vivo models, they have limitations as it is difficult to control and analyze the influence of specific variables within their tumor microenvironment. Thus, there is still a crucial need to develop tumor models that enable precise control of microenvironmental cues (e.g. matrix composition, soluble factors, cellular organization) to assess the efficacy of anti-cancer drugs. Herein, we report the development and validation of a 3D microfluidic invasion platform for anti-cancer drug studies. Our platform allowed for compartmentalization of tumor and stromal fibroblasts in a defined architecture, thereby enabling pharmacokinetic drug transport to a cell-dense tumor region. We analyzed the effect of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor, on the behavior of SUM159 breast cancer cells. Many HDAC inhibitors, including SAHA, have been a subject of controversy with highly conflicting results for the treatment of solid tumors in vitro as well as in clinical trials. We found that SAHA significantly inhibited cellular migration/proliferation, and decreased microtubule polarization.

BACKGROUND Histone deacetylase (HDAC) inhibitors are emerging as a new class of anti-cancer drugs that promote cancer cell apoptosis, and include suberoylanilide hydroxamic acid (SAHA). The aim of this study was to investigate the mechanism of SAHA-induced apoptosis in human prostate cancer cell lines, DU145 and PC-3. MATERIAL AND METHODS Cell lines, DU145 and PC-3, were studied before and after treatment with SAHA. The effects of SAHA treatment on cell proliferation were studied using the MTT cell proliferation assay. Annexin-V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) staining were used to study the effects of SAHA treatment on cell apoptosis. Western blotting, quantitative polymerase chain reaction (qPCR) and short interfering (si)RNA assays were performed to study the effects of SAHA treatment on apoptotic and cell cycle proteins and the Akt/FOXO3a signaling pathway. RESULTS Treatment with SAHA inhibited cell proliferation in human prostate cancer cell lines DU145 and PC-3 cells in a dose-dependent way. Cell cycle analysis and Annexin-V FITC/PI staining showed that treatment with SAHA resulted in G2/M cell cycle arrest and increased cell apoptosis in a dose-dependent way. Also, treatment with SAHA reduced the protein expression levels cyclin B and cyclin A2 and promoted the activation of FOXO3a by inhibiting Akt activation. Western blotting, the siRNA assay, and qPCR showed that FOXO3a, the Bcl-2 family of proteins, survivin, and FasL were involved in SAHA-induced apoptosis in prostate cancer cells grown in vitro. CONCLUSIONS Treatment with SAHA promoted apoptosis via the Akt/FOXO3a signaling pathway in prostate cancer cells in vitro.

Purpose: This study compared the efficacy and safety of suberoylanilide hydroxamic acid (SAHA) and mitomycin C (MMC) up to 4 months in the prevention of corneal haze induced by photorefractive keratectomy (PRK) in rabbits in vivo., Methods: Corneal haze in rabbits was produced with -9.00 diopter PRK. A single application of SAHA (25 μM) or MMC (0.02%) was applied topically immediately after PRK. Effects of the two drugs were analyzed by slit-lamp microscope, specular microscope, TUNEL assay, and immunofluorescence., Results: Single topical adjunct use of SAHA (25 μM) or MMC (0.02%) after PRK attenuated more than 95% corneal haze and myofibroblast formation (P < .001). SAHA did not reduce keratocyte density, cause keratocyte apoptosis, or increase immune cell infiltration compared to MMC (P < .01 or .001). Furthermore, SAHA dosing did not compromise corneal endothelial phenotype, density, or function in rabbit eyes, whereas MMC application did (P < .01 or .001)., Conclusions: SAHA and MMC significantly decreased corneal haze after PRK in rabbits in vivo. SAHA exhibited significantly reduced short- and long-term damage to the corneal endothelium compared to MMC in rabbits. SAHA is an effective and potentially safer alternative to MMC for the prevention of corneal haze after PRK. Clinical trials are warranted. [J Refract Surg. 2017;33(12):834-839.]., (Copyright 2017, SLACK Incorporated.)

Histone deacetylase (HDAC) inhibitors, especially suberoylanilide hydroxamic acid (SAHA) induce apoptosis in various cancer cells. Here, we investigated the effect of SAHA on apoptosis in lung cancer cells and addressed the role of reactive oxygen species (ROS), glutathione (GSH), and thioredoxin1 (Trx1) levels in this process. We also identified the miRNAs that down-regulate Trx1 expression at RNA level and thereby influence apoptotic cell death of SAHA increased intracellular ROS levels and promoted apoptotic cell death in cancerous cells but not in non-cancerous normal lung cells. Likewise, SAHA induced GSH depletion specifically in cancerous cells. While N-acetyl cysteine (NAC) reduced ROS level and reversed the effect of SAHA on cell death, L-buthionine sulfoximine (BSO) further enhanced GSH depletion, and promoted cell death. SAHA decreased the mRNA and protein levels of Trx1 in lung cancer cells. Knockdown/suppression of Trx1 intensified apoptosis in SAHA-treated lung cancer cells whereas overexpression of Trx1 prevented the cell death in these cells. SAHA up-regulated the level of miR-129-5p, which binds to 3' untranslated region (3'UTR) of Trx1 and down-regulates Trx1 expression. Down-regulation of Trx1 led to activation of apoptosis-signal regulating kinase (ASK), which induced apoptotic cell death by triggering ASK-JNK or ASK-p38 kinase pathway. In conclusion, changes in ROS and GSH levels in SAHA-treated lung cancer cells partially co-related with cell death. SAHA induced apoptosis via the down-regulation of Trx1, which was regulated by miR-129-5p., (© 2017 Wiley Periodicals, Inc.)

Suberoylanilide hydroxamic acid (SAHA) exerts marked anticancer effects via promotion of apoptosis, cell cycle arrest, and prevention of oncogene expression. In this study, serum metabolomics and artificial intelligence recognition were used to investigate SAHA toxicity. Forty rats (220 ± 20 g) were randomly divided into control and three SAHA groups (low, medium, and high); the experimental groups were treated with 12.3, 24.5, or 49.0 mg kg -1 SAHA once a day via intragastric administration. After 7 days, blood samples from the four groups were collected and analyzed by gas chromatography-mass spectrometry, and pathological changes in the liver were examined using microscopy. The results showed that increased levels of urea, oleic acid, and glutaconic acid were the most significant indicators of toxicity. Octadecanoic acid, pentadecanoic acid, glycerol, propanoic acid, and uric acid levels were lower in the high SAHA group. Microscopic observation revealed no obvious damage to the liver. Based on these data, a support vector machine (SVM) discrimination model was established that recognized the metabolic changes in the three SAHA groups and the control group with 100% accuracy. In conclusion, the main toxicity caused by SAHA was due to excessive metabolism of saturated fatty acids, which could be recognized by an SVM model.

Background: Kruppel-like factor 2 (KLF2) is an important zinc-finger transcription factor that maintains endothelial homeostasis by its anti-inflammatory, -thrombotic, -oxidative, and -proliferative effects in endothelial cells. In light of the potent vasoprotective effects of KLF2, modulating KLF2 expression or function could give rise to new therapeutic strategies to treat cardiovascular diseases., Methods and Results: High-throughput drug screening based on KLF2 promoter luciferase reporter assay was performed to screen KLF2 activators. Real-time PCR and western blot were used to detect gene and protein expression. Identified KLF2 activator was orally administered to ApoE -/- mice to evaluate anti-atherosclerotic efficacy. By screening 2400 compounds in the Spectrum library, we identified suberanilohydroxamic (SAHA) acid, also known as vorinostat as a pharmacological KLF2 activator through myocyte enhancer factor 2. We found that SAHA exhibited anti-inflammatory effects and attenuated monocyte adhesion to endothelial cells inflamed with tumor necrosis factor alpha. We further showed that the inhibitory effect of SAHA on endothelial inflammation and ensuing monocyte adhesion was KLF2 dependent using KLF2-deficient mouse lung endothelial cells or KLF2 small interfering RNA- depleted human endothelial cells. Importantly, we observed that oral administration of SAHA reduced diet-induced atherosclerotic lesion development in ApoE -/- mice without significant effect on serum lipid levels., Conclusions: These results demonstrate that SAHA has KLF2-dependent anti-inflammatory effects in endothelial cells and provide the proof of concept that KLF2 activation could be a promising therapeutic strategy for treating atherosclerosis., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Cisplatin is a widely used anticancer drug in clinic. However, it may induce drug resistance after a course of treatment and it is difficult to accumulate at tumor site selectively, which result in clinic failure and side effects. We successfully bound cisplatin with vorinostat (a FDA-approved histone deacetylase inhibitor) to form a supramolecular conjugate, which can further self-assemble into nanoparticles. The nanodrug can retain in blood stream for a long time, accumulate in tumor site and hydrolyze to release the two drugs for synergistic therapy. In vivo experiments highlighted the great advantage of the supramolecular nanodrug, because it ensured the two drugs reaching cancer tissue simutaneously. Free cisplatin or cisplatin/vorinostat mixture had negligible or limited effects on A549/DR tumor growth. On the contrary, the tumor inhibitory rate approached 99% with little systemic toxicity if the dose of cisplatin-vorinostat nanodrug reached 10mg/kg body weight, thus suggesting this supramolecular nanodrug as a promising treatment of drug resistance cancer., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Multiple Myeloma (MM) is currently incurable despite many novel therapies. Tumour Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a potential anti-tumour agent although effects as a single agent are limited. In this study, we investigated whether the Histone Deacetylase (HDAC) inhibitor SAHA can enhance TRAIL-induced apoptosis and target TRAIL resistance in both suspension culture, and 3D cell culture as a model of disseminated MM lesions that form in bone., Methods: The effects of SAHA and/or TRAIL in 6 Multiple Myeloma cell lines were assessed in both suspension cultures and in an Alginate-based 3D cell culture model. The effect of SAHA and/or TRAIL was assessed on apoptosis by assessment of nuclear morphology using Hoechst 33342/Propidium Iodide staining. Viable cell number was assessed by CellTiter-Glo luminescence assay, Caspase-8 and -9 activities were measured by Caspase-Glo™ assay kit. TRAIL-resistant cells were generated by culture of RPMI 8226 and NCI-H929 by acute exposure to TRAIL followed by selection of TRAIL-resistant cells., Results: TRAIL significantly induced apoptosis in a dose-dependent manner in OPM-2, RPMI 8226, NCI-H929, U266, JJN-3 MM cell lines and ADC-1 plasma cell leukaemia cells. SAHA amplified TRAIL responses in all lines except OPM-2, and enhanced TRAIL responses were both via Caspase-8 and -9. SAHA treatment induced growth inhibition that further increased in the combination treatment with TRAIL in MM cells. The co-treatment of TRAIL and SAHA reduced viable cell numbers all cell lines. TRAIL responses were further potentiated by SAHA in 3D cell culture in NCI-H929, RPMI 8226 and U266 at lower TRAIL + SAHA doses than in suspension culture. However TRAIL responses in cells that had been selected for TRAIL resistance were not further enhanced by SAHA treatment., Conclusions: SAHA is a potent sensitizer of TRAIL responses in both TRAIL sensitive and resistant cell lines, in both suspension and 3D culture, however SAHA did not sensitise TRAIL-sensitive cell populations that had been selected for TRAIL-resistance from initially TRAIL-sensitive populations. SAHA may increase TRAIL sensitivity in insensitive cells, but not in cells that have specifically been selected for acquired TRAIL-resistance., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The presence and degree of peripheral blood involvement in patients with cutaneous T-cell lymphoma (CTCL) portend a worse clinical outcome. Available systemic therapies for CTCL may variably decrease tumor burden and improve quality of life, but offer limited effects on survival; thus, novel approaches to the treatment of advanced stages of this non-Hodgkin lymphoma are clearly warranted. Mutational analyses of CTCL patient peripheral blood malignant cell samples suggested the antiapoptotic mediator B-cell lymphoma 2 (BCL2) as a potential therapeutic target. To test this, we developed a screening assay for evaluating the sensitivity of CTCL cells to targeted molecular agents, and compared a novel BCL2 inhibitor, venetoclax, alone and in combination with a histone deacetylase (HDAC) inhibitor, vorinostat or romidepsin. Peripheral blood CTCL malignant cells were isolated from 25 patients and exposed ex vivo to the 3 drugs alone and in combination, and comparisons were made to 4 CTCL cell lines (Hut78, Sez4, HH, MyLa). The majority of CTCL patient samples were sensitive to venetoclax, and BCL2 expression levels were negatively correlated ( r = -0.52; P = 018) to 50% inhibitory concentration values. Furthermore, this anti-BCL2 effect was markedly potentiated by concurrent HDAC inhibition with 93% of samples treated with venetoclax and vorinostat and 73% of samples treated with venetoclax and romidepsin showing synergistic effects. These data strongly suggest that concurrent BCL2 and HDAC inhibition may offer synergy in the treatment of patients with advanced CTCL. By using combination therapies and correlating response to gene expression in this way, we hope to achieve more effective and personalized treatments for CTCL., (© 2017 by The American Society of Hematology.)

Niemann-Pick type C (NPC) disease is an inherited, progressive neurodegenerative disorder principally caused by mutations in the NPC1 gene. NPC disease is characterized by the accumulation of unesterified cholesterol in the late endosomes (LE) and lysosomes (Ly) (LE/Ly). Vorinostat, a histone deacetylase inhibitor (HDACi), restores cholesterol homeostasis in fibroblasts derived from NPC patients; however, the exact mechanism by which Vorinostat restores cholesterol level is not known yet. In this study, we performed comparative proteomic profiling of the response of NPC1 I1061T fibroblasts to Vorinostat. After stringent statistical criteria to filter identified proteins, we observed 202 proteins that are differentially expressed in Vorinostat-treated fibroblasts. These proteins are members of diverse cellular pathways including the endomembrane dependent protein folding-stability-degradation-trafficking axis, energy metabolism, and lipid metabolism. Our study shows that treatment of NPC1 I1061T fibroblasts with Vorinostat not only enhances pathways promoting the folding, stabilization and trafficking of NPC1 (I1061T) mutant to the LE/Ly, but alters the expression of lysosomal proteins, specifically the lysosomal acid lipase (LIPA) involved in the LIPA->NPC2->NPC1 based flow of cholesterol from the LE/Ly lumen to the LE/Ly membrane. We posit that the Vorinostat may modulate numerous pathways that operate in an integrated fashion through epigenetic and post-translational modifications reflecting acetylation/deacetylation balance to help manage the defective NPC1 fold, the function of the LE/Ly system and/or additional cholesterol metabolism/distribution pathways, that could globally contribute to improved mitigation of NPC1 disease in the clinic based on as yet uncharacterized principles of cellular metabolism dictating cholesterol homeostasis., (© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.)

Histone deacetylase (HDAC) inhibitors modulate acetylation/deacetylation of histone and nonhistone proteins. They have been widely used for cancer treatment. However, there have been only a few studies investigating the effect of HDAC inhibitors on vascular tone regulation, most of which employed chronic treatment with HDAC inhibitors. In the present study, we found that two hydroxamate-based pan-HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA), could partially but acutely relax high extracellular K + -contracted mouse aortas. SAHA and TSA also attenuated the high extracellular K + -induced cytosolic Ca 2+ rise and inhibited L-type Ca 2+ channel current in whole-cell patch-clamp. These data demonstrate that SAHA could inhibit L-type Ca 2+ channels to cause vascular relaxation. In addition, SAHA and TSA dose dependently relaxed the arteries precontracted with phenylephrine. The relaxant effect of SAHA and TSA was greater in phenylephrine-precontracted arteries than in high K + -contracted arteries. Although part of the relaxant effect of SAHA and TSA on phenylephrine-precontracted arteries was related to L-type Ca 2+ channels, both agents could also induce relaxation via a mechanism independent of L-type Ca 2+ channels. Taken together, HDAC inhibitors SAHA and TSA can acutely relax blood vessels via their inhibitory action on L-type Ca 2+ channels and via another L-type Ca 2+ channel-independent mechanism., (Copyright © 2017 by The Author(s).)

Multiple myeloma is a fatal hematological malignancy with high rates of drug resistance and relapse. Vorinostat, a histone deacetylase inhibitor, has shown promise in enhancing efficacy when combined with current myeloma therapies. In this study, temporal changes of critical proteins and cell proliferation were measured in myeloma cells exposed to vorinostat. A model linking biomarker dynamics to cell proliferation was developed that captured vorinostat effects on signal transduction and cell viability. The model structure and parameters were fixed to describe tumor dynamics in vivo, and tumor-specific growth and death rate parameters were estimated. The signaling model captured tumor growth inhibition in murine xenografts for a range of dose levels and regimens. This model may be used as a mechanistic bridge to link vorinostat exposure to molecular events and pharmacodynamic (PD) outcomes. It may also provide a translational platform to explore vorinostat activity as a single agent and in combination regimens., (© 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Purpose: This study aimed at recommending pediatric dosages of the histone deacetylase (HDAC) inhibitor vorinostat and potentially more effective adult dosing regimens than the approved standard dosing regimen of 400 mg/day, using a comprehensive physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) modeling approach., Methods: A PBPK/PD model for vorinostat was developed for predictions in adults and children. It includes the maturation of relevant metabolizing enzymes. The PBPK model was expanded by (1) effect compartments to describe vorinostat concentration-time profiles in peripheral blood mononuclear cells (PBMCs), (2) an indirect response model to predict the HDAC inhibition, and (3) a thrombocyte model to predict the dose-limiting thrombocytopenia. Parameterization of drug and system-specific processes was based on published and unpublished in silico, in vivo, and in vitro data. The PBPK modeling software used was PK-Sim and MoBi., Results: The PBPK/PD model suggests dosages of 80 and 230 mg/m 2 for children of 0-1 and 1-17 years of age, respectively. In comparison with the approved standard treatment, in silico trials reveal 11 dosing regimens (9 oral, and 2 intravenous infusion rates) increasing the HDAC inhibition by an average of 31%, prolonging the HDAC inhibition by 181%, while only decreasing the circulating thrombocytes to a tolerable 53%. The most promising dosing regimen prolongs the HDAC inhibition by 509%., Conclusions: Thoroughly developed PBPK models enable dosage recommendations in pediatric patients and integrated PBPK/PD models, considering PD biomarkers (e.g., HDAC activity and platelet count), are well suited to guide future efficacy trials by identifying dosing regimens potentially superior to standard dosing regimens.

Objective To clarify the regulation role of tumor necrosis factor-related apoptosis inducing ligand-death receptor 5 (TRAIL-DR5) in cell autophagy induced by suberoylanilidehydroxamic acid (SAHA) in ER-positive breast cancer cell MCF-7. Methods The logarithmic growth phase of MCF-7 cells were divided into control group, SAHA treatment group, TRAIL-DR5 siRNA group and SAHA combined with TRAIL-DR5 siRNA treatment group. Western blotting was used to verify the results of TRAIL-DR5 gene silencing. Real-time quantitative PCR was performed to detect the mRNA levels of autophagy-related gene 9B (ATG9B), microtubule-associated protein 1 light chain 3A (LC3A) and LC3B in the different groups. The expressions of beclin-1, ATG3, ATG5, ATG7, ATG12, ATG16, ATG4A, ATG4B, ATG9B, LC3II, cathepsin B (CTSB) in the breast cancer cells were detected by Western blotting. The level of CTSB in the breast cancer cell culture supernatant was analyzed by ELISA. Immunofluorescence cytochemical staining was used to determine the expression and distribution of LC3II in the breast cancer cells. Results TRAIL-DR5 siRNA transfection significantly decreased the levels of TRAIL-DR5 in MCF-7 cells. After the knock-down of TRAIL-DR5 gene in MCF-7, the mRNA and protein levels of the autophagy-related factors in breast cancer cells markedly decreased, and the protein level of CTSB also decreased. After SAHA treatment of MCF-7 cells, the level of LC3II increased; when knockdown of TRAIL-DR5 receptor, LC3II level was significantly lower than that in the SAHA-alone-treated cells. Conclusion Down-regulating the TRAIL-DR5 gene can inhibit cell autophagy induced by SAHA in ER-positive MCF-7 breast cancer cells.

Purpose: The cure rate for patients with advanced head and neck squamous cell carcinoma (HNSCC) remains poor due to resistance to standard therapy primarily consisting of chemoradiation. As mutation of TP53 in HNSCC occurs in 60% to 80% of non-HPV-associated cases and is in turn associated with resistance to these treatments, more effective therapies are needed. In this study, we evaluated the efficacy of a regimen combining vorinostat and AZD1775 in HNSCC cells with a variety of p53 mutations. Experimental Design: Clonogenic survival assays and an orthotopic mouse model of oral cancer were used to examine the in vitro and in vivo sensitivity of high-risk mutant p53 HNSCC cell lines to vorinostat in combination with AZD1775. Cell cycle, replication stress, homologous recombination (HR), live cell imaging, RNA sequencing, and apoptosis analyses were performed to dissect molecular mechanisms. Results: We found that vorinostat synergizes with AZD1775 in vitro to inhibit growth of HNSCC cells harboring high-risk mutp53. These drugs interact synergistically to induce DNA damage, replication stress associated with impaired Rad51-mediated HR through activation of CDK1, and inhibition of Chk1 phosphorylation, culminating in an early apoptotic cell death during the S-phase of the cell cycle. The combination of vorinostat and AZD1775 inhibits tumor growth and angiogenesis in vivo in an orthotopic mouse model of oral cancer and prolongs animal survival. Conclusions: Vorinostat synergizes with AZD1775 in HNSCC cells with mutant p53 in vitro and in vivo A strategy combining HDAC and WEE1 inhibition deserves further clinical investigation in patients with advanced HNSCC. Clin Cancer Res; 23(21); 6541-54. ©2017 AACR ., (©2017 American Association for Cancer Research.)

The metastasis-associated protein 1(MTA1)/histone deacetylase (HDAC) unit is a cancer progression-related epigenetic regulator, which is overexpressed in hormone-refractory and metastatic prostate cancer (PCa). In our previous studies, we found a significantly increased MTA1 expression in a prostate-specific Pten-null mouse model. We also demonstrated that stilbenes, namely resveratrol and pterostilbene (Pter), affect MTA1/HDAC signaling, including deacetylation of tumor suppressors p53 and PTEN. In this study, we examined whether inhibition of MTA1/HDAC using combination of Pter and a clinically approved HDAC inhibitor, SAHA (suberoylanilide hydroxamic acid, vorinostat), which also downregulates MTA1, could block prostate tumor progression in vivo. We generated and utilized a luciferase reporter in a prostate-specific Pten-null mouse model (Pb-Cre + ; Pten f/f ; Rosa26 Luc/+ ) to evaluate the anticancer efficacy of Pter/SAHA combinatorial approach. Our data showed that Pter sensitized tumor cells to SAHA treatment resulting in inhibiting tumor growth and additional decline of tumor progression. These effects were dependent on the reduction of MTA1-associated proangiogenic factors HIF-1α, VEGF, and IL-1β leading to decreased angiogenesis. In addition, treatment of PCa cell lines in vitro with combined Pter and low dose SAHA resulted in more potent inhibition of MTA1/HIF-1α than by high dose SAHA alone. Our study provides preclinical evidence that Pter/SAHA combination treatment inhibits MTA1/HIF-1α tumor-promoting signaling in PCa. The beneficial outcome of combinatorial strategy using a natural agent and an approved drug for higher efficacy and less toxicity supports further development of MTA1-targeted therapies in PCa., (© 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Concomitant inhibition of multiple oncogenic pathways is a desirable goal in cancer therapy. To achieve such an outcome with a single molecule would simplify treatment regimes. Herein the core features of ruxolitinib (1), a marketed JAK1/2 inhibitor, have been merged with the HDAC inhibitor vorinostat (2), leading to new molecules that are bispecific targeted JAK/HDAC inhibitors. A preferred pyrazole substituted pyrrolopyrimidine, 24, inhibits JAK1 and HDACs 1, 2, 3, 6, and 10 with IC 50 values of less than 20 nM, is <100 nM potent against JAK2 and HDAC11, and is selective for the JAK family against a panel of 97 kinases. Broad cellular antiproliferative potency of 24 is supported by demonstration of JAK-STAT and HDAC pathway blockade in hematological cell lines. Methyl analogue 45 has an even more selective profile. This study provides new leads for assessment of JAK and HDAC pathway dual inhibiton achieved with a single molecule.

Alzheimer's disease (AD) comprises multifactorial ailments for which current therapeutic strategies remain insufficient to broadly address the underlying pathophysiology. Epigenetic gene regulation relies upon multifactorial processes that regulate multiple gene and protein pathways, including those involved in AD. We therefore took an epigenetic approach where a single drug would simultaneously affect the expression of a number of defined AD-related targets. We show that the small-molecule histone deacetylase inhibitor M344 reduces beta-amyloid (Aβ), reduces tau Ser 396 phosphorylation, and decreases both β-secretase (BACE) and APOEε4 gene expression. M344 increases the expression of AD-relevant genes: BDNF, α-secretase (ADAM10), MINT2, FE65, REST, SIRT1, BIN1, and ABCA7, among others. M344 increases sAPPα and CTFα APP metabolite production, both cleavage products of ADAM10, concordant with increased ADAM10 gene expression. M344 also increases levels of immature APP, supporting an effect on APP trafficking, concurrent with the observed increase in MINT2 and FE65, both shown to increase immature APP in the early secretory pathway. Chronic i.p. treatment of the triple transgenic (APP sw /PS1 M146V /Tau P301L ) mice with M344, at doses as low as 3 mg/kg, significantly prevented cognitive decline evaluated by Y-maze spontaneous alternation, novel object recognition, and Barnes maze spatial memory tests. M344 displays short brain exposure, indicating that brief pulses of daily drug treatment may be sufficient for long-term efficacy. Together, these data show that M344 normalizes several disparate pathogenic pathways related to AD. M344 therefore serves as an example of how a multitargeting compound could be used to address the polygenic nature of multifactorial diseases., Competing Interests: The authors declare no conflict of interest.

Purpose: The aim of this study was to fabricate a vorinostat (Zolinza™)-eluting nanofiber membrane-coated gastrointestinal (GI) stent and to study its antitumor activity against cholangiocarcinoma (CCA) cells in vitro and in vivo., Methods: Vorinostat and poly(DL-lactide-co-glycolide) dissolved in an organic solvent was sprayed onto a GI stent to make a nanofiber-coated stent using an electro-spinning machine. Intact vorinostat and vorinostat released from nanofibers was used to assess anticancer activity in vitro against various CCA cells. The antitumor activity of the vorinostat-eluting nanofiber membrane-coated stent was evaluated using HuCC-T1 bearing mice., Results: A vorinostat-incorporated polymer nanofiber membrane was formed on the surface of the GI stent. Vorinostat was continuously released from the nanofiber membrane over 10 days, and its release rate was higher in cell culture media than in phosphate-buffered saline. Released vorinostat showed similar anticancer activity against various CCA cells in vitro compared to that of vorinostat. Like vorinostat, vorinostat released from nanofibers induced acetylation of histone H4 and inhibited histone deacetylases 1⋅3⋅4/5/7 expression in vitro and in vivo. Furthermore, vorinostat nanofibers showed a higher tumor growth inhibition rate in HuCC-T1 bearing mice than vorinostat injections., Conclusion: Vorinostat-eluting nanofiber membranes showed significant antitumor activity against CCA cells in vitro and in vivo. We suggest the vorinostat nanofiber-coated stent may be a promising candidate for CCA treatment., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Since the lack of targeted treatment, triple-negative breast cancer (TNBC) has poor outcomes. Histone deacetylase inhibitors (HDACi) blocking the activity of specific HDACs have emerged as cancer therapeutic agents. However, the therapeutic efficiency is still not satisfactory for patients with solid tumor. We thus performed screening for the synergistic agents of Vorinostat (SAHA). The resulting candidate Simvastatin was obtained. The efficacy and mechanism of combination have been studied in TNBC cells. The synergism of SAHA and Simvastatin was evaluated by IC 50 of proliferation and combination index (CI). The antitumor activities of combination were further evaluated in TNBC cells. The pro-apoptotic effects were determined by flow cytometry and Western blot. Autophagosome-lysosome fusion was monitored using confocal microscope. The underlying mechanism was further studied by over-expressing of wild-type or inactive (C205S/C207S) Rab7 in compounds treated cells. The in vivo efficacy was also evaluated in mice. The combination of SAHA and Simvastatin had potent synergism in apoptosis of TNBC cells. It exerted pro-apoptosis effect by compromising the fusion between autophagosome and lysosome. Over-expressing of wild-type, but not inactive Rab7 rescued cells from apoptosis induced by the combinatory treatments. Mevalonate supplementation also decreased the combinatory treatment-induced apoptosis. These results indicate that the combinatory treatment enhances the apoptosis of TNBC cells by interrupting Rab7 prenylation and obstructing autophagosome-lysosome fusion. Combination between SAHA and Simvastatin could also significantly decrease the tumor growth in xenografted mice by inducing apoptosis and inhibiting Rab7 prenylation. Rab7 is a potential target for the combined effects of Simvastatin and SAHA., (Copyright © 2017. Published by Elsevier B.V.)

The oral histone deacetylase (HDAC) inhibitor (vorinostat) is safe and results in low incidence of acute graft-versus-host disease (GVHD) after reduced-intensity conditioning, related donor hematopoietic cell transplantation (HCT). However, its safety and efficacy in preventing acute GVHD in settings of heightened clinical risk that use myeloablative conditioning, unrelated donor (URD), and methotrexate are not known. We conducted a prospective, phase 2 study in this higher-risk setting. We enrolled 37 patients to provide 80% power to detect a significant difference in grade 2 to 4 acute GVHD of 50% compared with a reduction in target to 28%. Eligibility included adults with a hematological malignancy to receive myeloablative HCT from an available 8/8-HLA matched URD. Patients received GVHD prophylaxis with tacrolimus and methotrexate. Vorinostat (100 mg twice daily) was started on day -10 and continued through day +100 post-HCT. Median age was 56 years (range, 18-69 years), and 95% had acute myelogenous leukemia or high-risk myelodysplastic syndrome. Vorinostat was safe and tolerable. The cumulative incidence of grade 2 to 4 acute GVHD at day 100 was 22%, and for grade 3 to 4 it was 8%. The cumulative incidence of chronic GVHD was 29%; relapse, nonrelapse mortality, GVHD-free relapse-free survival, and overall survival at 1 year were 19%, 16%, 47%, and 76%, respectively. Correlative analyses showed enhanced histone (H3) acetylation in peripheral blood mononuclear cells and reduced interleukin 6 ( P = .028) and GVHD biomarkers (Reg3, P = .041; ST2, P = .002) at day 30 post-HCT in vorinostat-treated subjects compared with similarly treated patients who did not receive vorinostat. Vorinostat for GVHD prevention is an effective strategy that should be confirmed in a randomized phase 3 study. This trial was registered at www.clinicaltrials.gov as #NCT01790568., (© 2017 by The American Society of Hematology.)