panobinostat and Disease-Models--Animal

Histone deacetylase inhibitors (HDACi) sensitize homologous recombination (HR)-proficient human ovarian cancer cells to PARP inhibitors (PARPi). To investigate mechanisms of anti-tumor effects of combined HDACi/PARPi treatment we performed transcriptome analysis in HR- proficient human ovarian cancer cells and tested drug effects in established immunocompetent mouse ovarian cancer models. Human SKOV-3 cells were treated with vehicle (Con), olaparib (Ola), panobinostat (Pano) or Pano+Ola and RNA-seq analysis performed. DESeq2 identified differentially expressed HR repair and immune transcripts. Luciferised syngeneic mouse ovarian cancer cells (ID8-luc) were treated with the HDACi panobinostat alone or combined with olaparib and effects on cell viability, apoptosis, DNA damage and HR efficiency determined. C57BL/6 mice with intraperitoneally injected ID8-luc cells were treated with panobinostat and/or olaparib followed by assessment of tumor burden, markers of cell proliferation, apoptosis and DNA damage, tumor-infiltrating T cells and macrophages, and other immune cell populations in ascites fluid. There was a significant reduction in expression of 20/37 HR pathway genes by Pano+Ola, with immune and inflammatory-related pathways also significantly enriched by the combination. In ID8 cells, Pano+Ola decreased cell viability, HR repair, and enhanced DNA damage. Pano+Ola also co-operatively reduced tumor burden and proliferation, increased tumor apoptosis and DNA damage, enhanced infiltration of CD8+ T cells into tumors, and decreased expression of M2-like macrophage markers. In conclusion, panobinostat in combination with olaparib targets ovarian tumors through both direct cytotoxic and indirect immune-modulating effects.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Disease Models, Animal; Drug Synergism; Female; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Immunomodulation; Mice; Ovarian Neoplasms; Panobinostat; Phthalazines; Piperazines; Recombinational DNA Repair; Xenograft Model Antitumor Assays

Crescentic glomerulonephritis is characterized by vascular necrosis and parietal epithelial cell hyperplasia in the space surrounding the glomerulus, resulting in the formation of crescents. Little is known about the molecular mechanisms driving this process. Inducing crescentic glomerulonephritis in two Pax2Cre reporter mouse models revealed that crescents derive from clonal expansion of single immature parietal epithelial cells. Preemptive and delayed histone deacetylase inhibition with panobinostat, a drug used to treat hematopoietic stem cell disorders, attenuated crescentic glomerulonephritis with recovery of kidney function in the two mouse models. Three-dimensional confocal microscopy and stimulated emission depletion superresolution imaging of mouse glomeruli showed that, in addition to exerting an anti-inflammatory and immunosuppressive effect, panobinostat induced differentiation of an immature hyperplastic parietal epithelial cell subset into podocytes, thereby restoring the glomerular filtration barrier. Single-cell RNA sequencing of human renal progenitor cells in vitro identified an immature stratifin-positive cell subset and revealed that expansion of this stratifin-expressing progenitor cell subset was associated with a poor outcome in human crescentic glomerulonephritis. Treatment of human parietal epithelial cells in vitro with panobinostat attenuated stratifin expression in renal progenitor cells, reduced their proliferation, and promoted their differentiation into podocytes. These results offer mechanistic insights into the formation of glomerular crescents and demonstrate that selective targeting of renal progenitor cells can attenuate crescent formation and the deterioration of kidney function in crescentic glomerulonephritis in mice.

Topics: Animals; Disease Models, Animal; Glomerulonephritis; Humans; Kidney; Mice; Panobinostat; Podocytes; Stem Cells

Topics: Aminopropionitrile; Animals; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortic Dissection; Cefixime; Disease Models, Animal; Fluoroquinolones; Histone Deacetylase Inhibitors; Male; Mice, Inbred C57BL; Panobinostat; Risk Assessment; Risk Factors; Severity of Illness Index

Osteoarthritis (OA) is the most common articular degenerative disease characterized by chronic pain, joint inflammation, and movement limitations, which are significantly influenced by aberrant epigenetic modifications of numerous OA-susceptible genes. Recent studies revealed that both the abnormal activation and differential expression of histone deacetylases (HDACs) might contribute to OA pathogenesis. In this study, we investigated the chondroprotective effects of a marine-derived HDAC inhibitor, panobinostat, on anterior cruciate ligament transection (ACLT)-induced experimental OA rats. The intra-articular administration of 2 or 10 µg of panobinostat (each group,

Topics: Animals; Anterior Cruciate Ligament; Anterior Cruciate Ligament Injuries; Cartilage Diseases; Cartilage, Articular; Chondrocytes; Disease Models, Animal; Histone Deacetylase Inhibitors; Male; Osteoarthritis, Knee; Pain; Panobinostat; Rats; Rats, Wistar; Weight-Bearing

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

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

Mutations in the gene encoding for the histone acetyltransferase (HAT) CREBBP are common driver events in multiple types of human cancer, such as small cell lung cancer (SCLC) or Sonic Hedgehog medulloblastoma (SHH MB). Therefore, therapeutic options targeting such alterations are highly desired. We used human cell lines from SCLC as well as primary mouse tumor cells and genetically engineered mouse models for SHH MB to test treatment options with histone deacetylase inhibitors (HDACi) in CREBBP wild-type and mutated tumors. In contrast to CREBBP wild-type SCLC cells, CREBBP-mutated SCLC cells showed significantly lower IC

Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Cell Line, Tumor; Cell Proliferation; Cerebellar Neoplasms; CREB-Binding Protein; Disease Models, Animal; Drug Screening Assays, Antitumor; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Medulloblastoma; Mice; Mice, Transgenic; Panobinostat; Primary Cell Culture; Smoothened Receptor

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive, incurable cancer with a 20% 1 year survival rate. While standard-of-care therapy can prolong life in a small fraction of cases, PDAC is inherently resistant to current treatments, and novel therapies are urgently required. Histone deacetylase (HDAC) inhibitors are effective in killing pancreatic cancer cells in in vitro PDAC studies, and although there are a few clinical studies investigating combination therapy including HDAC inhibitors, no HDAC drug or combination therapy with an HDAC drug has been approved for the treatment of PDAC. We developed an inhibitor of HDACs, AES-135, that exhibits nanomolar inhibitory activity against HDAC3, HDAC6, and HDAC11 in biochemical assays. In a three-dimensional coculture model, AES-135 kills low-passage patient-derived tumor spheroids selectively over surrounding cancer-associated fibroblasts and has excellent pharmacokinetic properties in vivo. In an orthotopic murine model of pancreatic cancer, AES-135 prolongs survival significantly, therefore representing a candidate for further preclinical testing.

Topics: Animals; Apoptosis; Benzamides; Cell Line, Tumor; Cell Proliferation; Coculture Techniques; Disease Models, Animal; Histone Deacetylase Inhibitors; Humans; Hydrocarbons, Fluorinated; Hydroxamic Acids; Mice; Pancreatic Neoplasms; Sulfonamides

The clinical use of MEK inhibitors in uveal melanoma is limited by the rapid acquisition of resistance. This study has used multiomics approaches and drug screens to identify the pan-HDAC inhibitor panobinostat as an effective strategy to limit MEK inhibitor resistance.. Together, our studies have identified GPCR-mediated YAP activation and RTK-driven AKT signaling as key pathways involved in the escape of uveal melanoma cells from MEK inhibition. We further demonstrate that HDAC inhibition is a promising combination partner for MEK inhibitors in advanced uveal melanoma.

Topics: Animals; Cell Cycle Proteins; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Disease Progression; Drug Resistance, Neoplasm; Drug Synergism; Histone Deacetylase Inhibitors; Humans; MAP Kinase Signaling System; Melanoma; Mice; Panobinostat; Phosphatidylinositol 3-Kinases; Protein Kinase Inhibitors; Proteome; Proteomics; Proto-Oncogene Proteins c-akt; Pyridones; Pyrimidinones; Receptor Tyrosine Kinase-like Orphan Receptors; Receptor, IGF Type 1; Receptors, G-Protein-Coupled; Signal Transduction; Transcription Factors; Uveal Neoplasms; Xenograft Model Antitumor Assays

Hepatic cystogenesis in polycystic liver disease (PLD) is associated with abnormalities in multiple cellular processes, including elevated cAMP and overexpression of histone deacetylase 6 (HDAC6). Disease progression in polycystic kidney (PCK) rats (an animal model of PLD) is attenuated by inhibition of either cAMP production or HDAC6. Therefore, we hypothesized that concurrent targeting of HDAC6 and cAMP would synergistically reduce cyst growth. Changes in hepatorenal cystogenesis were examined in PCK rats treated with a pan-HDAC inhibitor, panobinostat; three specific HDAC6 inhibitors, ACY-1215, ACY-738, and ACY-241; and a combination of ACY-1215 and the somatostatin receptor analogue, pasireotide. We also assessed effects of ACY-1215 and pasireotide alone and in combination on cell proliferation, cAMP production, and expression of acetylated α-tubulin in vitro in cultured cholangiocytes and the length of primary cilia and the frequency of ciliated cholangiocytes in vivo in PCK rats. Panobinostat and all three HDAC6 inhibitors decreased hepatorenal cystogenesis in PCK rats. ACY-1215 was more effective than other HDAC inhibitors and was chosen for combinational treatment. ACY-1215 + pasireotide combination synergistically reduced cyst growth and increased length of primary cilia in PCK rats. In cultured cystic cholangiocytes, ACY-1215 + pasireotide combination concurrently decreased cell proliferation and inhibited cAMP levels. These data suggest that the combination of drugs that inhibit HDAC6 and cAMP may be an effective therapy for PLD.

Topics: Acetylation; Animals; Bile Ducts; Cell Proliferation; Cilia; Cyclic AMP; Cysts; Disease Models, Animal; Drug Synergism; Female; Histone Deacetylase 6; Histone Deacetylase Inhibitors; Hydroxamic Acids; Liver Diseases; Male; Panobinostat; Pyrimidines; Rats; Receptors, Somatostatin; Somatostatin; Tubulin

OBJECTIVE The pan-histone deacetylase inhibitor panobinostat has preclinical efficacy against diffuse intrinsic pontine glioma (DIPG), and the oral formulation has entered a Phase I clinical trial. However, panobinostat does not cross the blood-brain barrier in humans. Convection-enhanced delivery (CED) is a novel neurosurgical drug delivery technique that bypasses the blood-brain barrier and is of considerable clinical interest in the treatment of DIPG. METHODS The authors investigated the toxicity, distribution, and clearance of a water-soluble formulation of panobinostat (MTX110) in a small- and large-animal model of CED. Juvenile male Wistar rats (n = 24) received panobinostat administered to the pons by CED at increasing concentrations and findings were compared to those in animals that received vehicle alone (n = 12). Clinical observation continued for 2 weeks. Animals were sacrificed at 72 hours or 2 weeks following treatment, and the brains were subjected to neuropathological analysis. A further 8 animals received panobinostat by CED to the striatum and were sacrificed 0, 2, 6, or 24 hours after infusion, and their brains explanted and snap-frozen. Tissue-drug concentration was determined by liquid chromatography tandem mass spectrometry (LC-MS/MS). Large-animal toxicity was investigated using a clinically relevant MRI-guided translational porcine model of CED in which a drug delivery system designed for humans was used. Panobinostat was administered at 30 μM to the ventral pons of 2 juvenile Large White-Landrace cross pigs. The animals were subjected to clinical and neuropathological analysis, and findings were compared to those obtained in controls after either 1 or 2 weeks. Drug distribution was determined by LC-MS/MS in porcine white and gray matter immediately after CED. RESULTS There were no clinical or neuropathological signs of toxicity up to an infused concentration of 30 μM in both small- and large-animal models. The half-life of panobinostat in rat brain after CED was 2.9 hours, and the drug was observed to be distributed in porcine white and gray matter with a volume infusion/distribution ratio of 2 and 3, respectively. CONCLUSIONS CED of water-soluble panobinostat, up to a concentration of 30 μM, was not toxic and was distributed effectively in normal brain. CED of panobinostat warrants clinical investigation in patients with DIPG.

Topics: Animals; Antineoplastic Agents; Brain Stem Neoplasms; Calcium-Binding Proteins; Chromatography, Liquid; Convection; Disease Models, Animal; Dose-Response Relationship, Drug; Glial Fibrillary Acidic Protein; Glioma; Magnetic Resonance Imaging; Male; Microfilament Proteins; Panobinostat; Phosphopyruvate Hydratase; Rats; Rats, Wistar; Swine; Tandem Mass Spectrometry; Time Factors; Tissue Distribution; Xenograft Model Antitumor Assays

Topics: Animals; Animals, Genetically Modified; Cell Differentiation; Disease Models, Animal; Female; Histone Deacetylase Inhibitors; Humans; Huntingtin Protein; Huntington Disease; Hydroxamic Acids; Indoles; Lateral Ventricles; Male; Mice, Transgenic; Mutation; Neurons; Panobinostat; Rats

Expression of MHC class II pathway proteins in ovarian cancer correlates with prolonged survival. Murine and human ovarian cancer cells were treated with epigenetic modulators - histone deacetylase inhibitors and a DNA methyltransferase inhibitor. mRNA and protein expression of the MHC II pathway were evaluated by qPCR and flow cytometry. Treatment with entinostat and azacytidine of ID8 cells in vitro increased mRNA levels of Cd74, Ciita, and H2-Aa, H2-Eb1. MHC II and CD74 protein expression were increased after treatment with either agent. A dose dependent response in mRNA and protein expression was seen with entinostat. Combination treatment showed higher MHC II protein expression than with single agent treatment. In patient derived xenografts, CIITA, CD74, and MHC II mRNA transcripts were significantly increased after combination treatment. Expression of MHC II on ovarian tumors in MISIIR-Tag mice was increased with both agents relative to control. Combination treatment significantly reduced ID8 tumor growth in immune-competent mice. Epigenetic treatment increases expression of MHC II on ovarian cancer cells and impedes tumor growth. This approach warrants further study in ovarian cancer patients.

Topics: Animals; Antimetabolites, Antineoplastic; Azacitidine; Benzamides; Cell Line, Tumor; Disease Models, Animal; DNA Methylation; Dose-Response Relationship, Drug; Drug Synergism; Epigenesis, Genetic; Female; Gene Expression Regulation, Neoplastic; Histocompatibility Antigens Class II; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Mice; Ovarian Neoplasms; Panobinostat; Pyridines; RNA, Messenger; Transcription, Genetic; Tumor Burden; Xenograft Model Antitumor Assays

The pan-histone deacetylase inhibitor panobinostat is a potential therapy for malignant glioma, but it is water insoluble and does not cross the blood-brain barrier when administered systemically. In this article, we describe the in vitro and in vivo efficacy of a novel water-soluble nano-micellar formulation of panobinostat designed for administration by convection enhanced delivery (CED).. The in vitro efficacy of panobinostat-loaded nano-micelles against rat F98, human U87-MG and M059K glioma cells and against patient-derived glioma stem cells was measured using a cell viability assay. Nano-micelle distribution in rat brain was analyzed following acute CED using rhodamine-labeled nano-micelles, and toxicity was assayed using immunofluorescent microscopy and synaptophysin enzyme-linked immunosorbent assay. We compared the survival of the bioluminescent syngenic F98/Fischer344 rat glioblastoma model treated by acute CED of panobinostat-loaded nano-micelles with that of untreated and vehicle-only-treated controls.. Nano-micellar panobinostat is cytotoxic to rat and human glioma cells in vitro in a dose-dependent manner following short-time exposure to drug. Fluorescent rhodamine-labelled nano-micelles distribute with a volume of infusion/volume of distribution (Vi/Vd) ratio of four and five respectively after administration by CED. Administration was not associated with any toxicity when compared to controls. CED of panobinostat-loaded nano-micelles was associated with significantly improved survival when compared to controls (n=8 per group; log-rank test,. CED of nano-micellar panobinostat represents a potential novel therapeutic option for malignant glioma and warrants translation into the clinic.

Topics: Animals; Brain Neoplasms; Cell Death; Cell Line, Tumor; Cell Survival; Convection; Disease Models, Animal; Drug Delivery Systems; Fluorescent Antibody Technique; Glioma; Humans; Hydroxamic Acids; Indoles; Micelles; Nanoparticles; Panobinostat; Poloxamer; Rats, Inbred F344; Rats, Wistar; Survival Analysis

PI3K (phosphoinositide 3-kinase)/AKT and RAS/MAPK (mitogen-activated protein kinase) pathway coactivation in the prostate epithelium promotes both epithelial-mesenchymal transition (EMT) and metastatic castration-resistant prostate cancer (mCRPC), which is currently incurable. To study the dynamic regulation of the EMT process, we developed novel genetically defined cellular and in vivo model systems from which epithelial, EMT and mesenchymal-like tumor cells with Pten deletion and Kras activation can be isolated. When cultured individually, each population has the capacity to regenerate all three tumor cell populations, indicative of epithelial-mesenchymal plasticity. Despite harboring the same genetic alterations, mesenchymal-like tumor cells are resistant to PI3K and MAPK pathway inhibitors, suggesting that epigenetic mechanisms may regulate the EMT process, as well as dictate the heterogeneous responses of cancer cells to therapy. Among differentially expressed epigenetic regulators, the chromatin remodeling protein HMGA2 is significantly upregulated in EMT and mesenchymal-like tumors cells, as well as in human mCRPC. Knockdown of HMGA2, or suppressing HMGA2 expression with the histone deacetylase inhibitor LBH589, inhibits epithelial-mesenchymal plasticity and stemness activities in vitro and markedly reduces tumor growth and metastasis in vivo through successful targeting of EMT and mesenchymal-like tumor cells. Importantly, LBH589 treatment in combination with castration prevents mCRPC development and significantly prolongs survival following castration by enhancing p53 and androgen receptor acetylation and in turn sensitizing castration-resistant mesenchymal-like tumor cells to androgen deprivation therapy. Taken together, these findings demonstrate that cellular plasticity is regulated epigenetically, and that mesenchymal-like tumor cell populations in mCRPC that are resistant to conventional and targeted therapies can be effectively treated with the epigenetic inhibitor LBH589.

Topics: Animals; Blotting, Western; Cell Line, Tumor; Disease Models, Animal; Epithelial-Mesenchymal Transition; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Male; Mice, Inbred NOD; Mice, Knockout; Mice, SCID; Mice, Transgenic; Mitogen-Activated Protein Kinases; Neoplasm Metastasis; Panobinostat; Phosphatidylinositol 3-Kinases; Prostatic Neoplasms, Castration-Resistant; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins p21(ras); PTEN Phosphohydrolase; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction

Deacetylase inhibitors have recently been established as a novel therapeutic approach to solid and hematologic cancers and have also been demonstrated to possess anti-angiogenic properties. Although these compounds show a good efficacy in vitro and in vivo, no data on monitoring and predicting treatment response are currently available. We therefore investigated the effect of the pan-deacetylase inhibitor panobinostat (LBH589) on gastrointestinal cancer models and the suitability of 2-[(18)F]FGlc-RGD as a specific agent for imaging integrin αvβ3 expression during tumor angiogenesis using small animal positron emission tomography (PET).. The effect of panobinostat on cell viability in vitro was assessed with a label-free impedance based real-time analysis. Nude mice bearing HT29 and HepG2 tumors were treated with daily i.p. injections of 10mg/kg panobinostat for 4 weeks. During this time, tumor size was determined with a calliper and mice were repeatedly subjected to PET imaging. Tumor tissues were analyzed immunohistochemically with a focus on proliferation and endothelial cell markers (Ki-67, Meca-32) and by Western blot applying specific markers of apoptosis.. In vitro, panobinostat inhibited the proliferation of HepG2 and HT29 cells. Contrary to the situation in HepG2 tumors in vivo, where panobinostat treatment is known to reduce proliferation and vascularization resulting in a decreased tumor growth, HT29 tumors did not show any effect on these parameters. We demonstrated by Western blotting, that panobinostat induced apoptosis in HT29 tumors in vivo. Longitudinal PET imaging studies in HepG2 tumor-bearing mice using 2-[(18)F]FGlc-RGD demonstrated that the standard uptake value (SUVmax) in HepG2 tumors was significantly decreased by 39% at day 7 after treatment. The comparative PET study using HT29 tumor-bearing animals did not reveal any response of the tumors to panobinostat treatment.. Small-animal PET imaging using 2-[(18)F]FGlc-RGD was successfully applied to the non-invasive monitoring of the HepG2-tumor response to panobinostat in nude mice early after begin of treatment. Thus, PET imaging of angiogenesis using 2-[(18)F]FGlc-RGD could be a valuable tool to monitor panobinostat therapy in further preclinical studies.. When successfully translated to the clinical surrounding, PET imaging of angiogenesis could therefore facilitate therapy planning and monitoring of therapy success with panobinostat in hepatocellular carcinoma.

Topics: Adenocarcinoma; Angiogenesis Inhibitors; Animals; Caspase 3; Cell Proliferation; Colonic Neoplasms; Disease Models, Animal; Enzyme Activation; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Histone Deacetylase Inhibitors; HT29 Cells; Humans; Hydroxamic Acids; Indoles; Male; Mice; Mice, Nude; Neovascularization, Pathologic; Panobinostat; Poly(ADP-ribose) Polymerases; Positron-Emission Tomography; Prognosis; Proteolysis; Treatment Outcome

Neuroblastoma is the most common extra-cranial malignancy in childhood and accounts for ∼15% of childhood cancer deaths. Amplification of MYCN in neuroblastoma is associated with aggressive disease and predicts for poor prognosis. Novel therapeutic approaches are therefore essential to improving patient outcomes in this setting. The histone deacetylases are known to interact with N-Myc and regulate numerous cellular processes via epigenetic modulation, including differentiation. In this study, we used the TH-MYCN mouse model of neuroblastoma to investigate the antitumor activity of the pan-HDAC inhibitor, panobinostat. In particular we sought to explore the impact of long term, continuous panobinostat exposure on the epigenetically driven differentiation process. Continuous treatment of tumor bearing TH-MYCN transgenic mice with panobinostat for nine weeks led to a significant improvement in survival as compared with mice treated with panobinostat for a three-week period. Panobinostat induced rapid tumor regression with no regrowth observed following a nine-week treatment period. Initial tumor response was associated with apoptosis mediated via upregulation of BMF and BIM. The process of terminal differentiation of neuroblastoma into benign ganglioneuroma, with a characteristic increase in S100 expression and reduction of N-Myc expression, occurred following prolonged exposure to the drug. RNA-sequencing analysis of tumors from treated animals confirmed significant upregulation of gene pathways associated with apoptosis and differentiation. Together our data demonstrate the potential of panobinostat as a novel therapeutic strategy for high-risk neuroblastoma patients.

Topics: Animals; Apoptosis; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Female; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Male; Mice; Mice, Transgenic; Neuroblastoma; Panobinostat; Proto-Oncogene Proteins c-myc; S100 Proteins; Survival Analysis

Pre-clinical studies have demonstrated that natural and synthetic histone deacetylase (HDAC) inhibitors can impede the in vitro and in vivo growth of cell lines from a variety of gynecologic and other malignancies. We investigated the anti-tumor activity of panobinostat (LBH589) both in vitro and in vivo as either a single agent or in combination with conventional cytotoxic chemotherapy using patient-derived xenograft (PDX) models of primary serous ovarian tumors.. The ovarian cancer cell lines OVCAR8, SKOV3 and their paclitaxel-resistant derivatives OVCAR8-TR and SKOV3-TR were treated with increasing doses of LBH589. The effect of LBH589 on cell viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Serially transplanted primary human high-grade serous ovarian adenocarcinoma tissue was utilized to generate xenografts in 6-week old female NOD/SCID mice. The mice were then randomized into one of 4 treatment groups: (1) vehicle control; (2) paclitaxel and carboplatin (P/C); (3) LBH589; or (4) P/C + LBH589. Mice were treated for 21 days and tumor volumes and mouse weights were obtained every 3 days. These experiments were performed in triplicate with three different patient derived tumors. Wilcoxan rank-sum testing was utilized to assess tumor volume differences.. In vitro treatment with LBH589 significantly reduced the viability of both taxol-sensitive and taxol-resistant ovarian cancer cell lines (p < 0.01). In vivo treatment with LBH589 alone appeared tumorstatic and reduced tumor growth when compared to vehicle treatment (p < 0.007) after 21 days. This single agent activity was confirmed in two additional experiments with other PDX tumors (p < 0.03, p < 0.05). A potential additive effect of LBH589 and P/C, manifested as enhanced tumor regression with the addition of LBH589 compared to vehicle (p < 0.02), in one of the three analyzed serous PDX models.. Our findings suggest that pan-HDAC inhibition with panobinostat precludes the growth of ovarian cancer cell lines in vitro and PDXs in vivo. Added benefit of LBH589 to standard P/C therapy was observed in one of three PDX models suggesting improved response in a subset of serous ovarian cancers.

Topics: Animals; Antineoplastic Agents; Biomarkers; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Mice; Mice, Inbred NOD; Mice, SCID; Neoplasm Grading; Ovarian Neoplasms; Panobinostat; Tumor Burden; Xenograft Model Antitumor Assays

Modulation of gene transcription by HDAC inhibitors has been shown repeatedly to be neuroprotective in cellular, invertebrate, and rodent models of Huntington's disease (HD). It has been difficult to translate these treatments to the clinic, however, because existing compounds have limited potency or brain bioavailability.. In the present study, we assessed the therapeutic potential of LBH589, an orally bioavailable hydroxamic acid-derived nonselective HDAC inhibitor in mouse models of HD.. The efficacy of LBH589 is tested in two HD mouse models using various biochemical, behavioral and neuropathological outcome measures.. We show that LBH589 crosses the blood brain barrier; induces histone hyperacetylation and prevents striatal neuronal shrinkage in R6/2 HD mice. In full-length knock-in HD mice LBH589-treatment improves motor performance and reduces neuronal atrophy.. Our efficacious results of LBH589 in fragment and full-length mouse models of HD suggest that LBH589 is a promising candidate for clinical assessment in HD patients and provides confirmation that non-selective HDAC inhibitors can be viable clinical candidates.

Topics: Animals; Atrophy; Corpus Striatum; Disease Models, Animal; Female; Gene Knock-In Techniques; Histone Deacetylase Inhibitors; Histones; Huntington Disease; Hydroxamic Acids; Indoles; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Motor Activity; Neurons; Neuroprotective Agents; Panobinostat

The aim of this study is to investigate the efficacy of combining a histone deacetylase inhibitor (LBH589) and a breast cancer stem cells (BCSC)-targeting agent (salinomycin) as a novel combination therapy for triple-negative breast cancer (TNBC). We performed in vitro studies using the TNBC cell lines to examine the combined effect. We used the mammosphere and ALDEFLUOR assays to estimate BCSC self-renewal capacity and distribution of BCSCs, respectively. Synergistic analysis was performed using CalcuSyn software. For in vivo studies, aldehyde dehydrogenase 1 ALDH1-positive cells were injected into non-obese diabetic/severe combined immunodeficiency gamma (NSG) mice. After tumor formation, mice were treated with LBH589, salinomycin, or in combination. In a second mouse model, HCC1937 cells were first treated with each treatment and then injected into NSG mice. For mechanistic analysis, immunohistochemistry and Western blot analysis were performed using cell and tumor samples. HCC1937 cells displayed BCSC properties including self-renewal capacity, an ALDH1-positive cell population, and the ability to form tumors. Treatment of HCC1937 cells with LBH589 and salinomycin had a potent synergistic effect inhibiting TNBC cell proliferation, ALDH1-positive cells, and mammosphere growth. In xenograft mouse models treated with LBH589 and salinomycin, the drug combination effectively and synergistically inhibited tumor growth of ALDH1-positive cells. The drug combination exerted its effects by inducing apoptosis, arresting the cell cycle, and regulating epithelial-mesenchymal transition (EMT). Combination of LBH589 and salinomycin has a synergistic inhibitory effect on TNBC BCSCs by inducing apoptosis, arresting the cell cycle, and regulating EMT; with no apparent associated severe toxicity. This drug combination could therefore offer a new targeted therapeutic strategy for TNBC and warrants further clinical study in patients with TNBC.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Cell Self Renewal; Cell Transformation, Neoplastic; Disease Models, Animal; Drug Synergism; Epithelial-Mesenchymal Transition; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Mice; Neoplastic Stem Cells; Panobinostat; Pyrans; Triple Negative Breast Neoplasms; Tumor Burden; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Diffuse intrinsic pontine glioma (DIPG) is a fatal childhood cancer. We performed a chemical screen in patient-derived DIPG cultures along with RNA-seq analyses and integrated computational modeling to identify potentially effective therapeutic strategies. The multi-histone deacetylase inhibitor panobinostat demonstrated therapeutic efficacy both in vitro and in DIPG orthotopic xenograft models. Combination testing of panobinostat and the histone demethylase inhibitor GSK-J4 revealed that the two had synergistic effects. Together, these data suggest a promising therapeutic strategy for DIPG.

Topics: Animals; Benzazepines; Brain Stem Neoplasms; Disease Models, Animal; Drug Synergism; Glioma; Humans; Hydroxamic Acids; Indoles; Panobinostat; Pyrimidines; Sequence Analysis, RNA; Xenograft Model Antitumor Assays

A phase I/II trial for glioblastoma with the oncolytic adenovirus Delta24-RGD was recently completed. Delta24-RGD conditionally replicates in cells with a disrupted retinoblastoma-pathway and enters cells via αvβ3/5 integrins. Glioblastomas are differentially sensitive to Delta24-RGD. HDAC inhibitors (HDACi) affect integrins and share common cell death pathways with Delta24-RGD. We studied the combination treatment effects of HDACi and Delta24-RGD in patient-derived glioblastoma stem-like cells (GSC), and we determined the most effective HDACi.. SAHA, Valproic Acid, Scriptaid, MS275 and LBH589 were combined with Delta24-RGD in fourteen distinct GSCs. Synergy was determined by Chou Talalay method. Viral infection and replication were assessed using luciferase and GFP encoding vectors and hexon-titration assays. Coxsackie adenovirus receptor and αvβ3 integrin levels were determined by flow cytometry. Oncolysis and mechanisms of cell death were studied by viability, caspase-3/7, LDH and LC3B/p62, phospho-p70S6K. Toxicity was studied on normal human astrocytes. MGMT promotor methylation status, TCGA classification, Rb-pathway and integrin gene expression levels were assessed as markers of responsiveness.. Scriptaid and LBH589 acted synergistically with Delta24-RGD in approximately 50% of the GSCs. Both drugs moderately increased αvβ3 integrin levels and viral infection in responding but not in non-responding GSCs. LBH589 moderately increased late viral gene expression, however, virus titration revealed diminished viral progeny production by both HDACi, Scriptaid augmented caspase-3/7 activity, LC3B conversion, p62 and phospho-p70S6K consumption, as well as LDH levels. LBH589 increased LDH and phospho-p70S6K consumption. Responsiveness correlated with expression of various Rb-pathway genes and integrins. Combination treatments induced limited toxicity to human astrocytes.. LBH589 and Scriptaid combined with Delta24-RGD revealed synergistic anti-tumor activity in a subset of GSCs. Both HDACi moderately augmented viral infection and late gene expression, but slightly reduced progeny production. The drugs differentially activated multiple cell death pathways. The limited toxicity on astrocytes supports further evaluation of the proposed combination therapies.

Topics: Adenoviridae; Animals; Apoptosis; Astrocytes; Autophagy; Brain Neoplasms; Cell Survival; Disease Models, Animal; DNA Methylation; DNA Modification Methylases; DNA Repair Enzymes; Dose-Response Relationship, Drug; Glioblastoma; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Hydroxylamines; Indoles; Integrin alphaVbeta3; Mice; Mutation; Neoplastic Stem Cells; Oncolytic Virotherapy; Oncolytic Viruses; Panobinostat; Promoter Regions, Genetic; Quinolines; Tumor Suppressor Protein p53; Tumor Suppressor Proteins; Virus Replication; Xenograft Model Antitumor Assays

Epigenetic modifying enzymes such as histone deacetylases (HDACs), p300, and PRMT1 are recruited by AML1/ETO, the pathogenic protein for t(8;21) acute myeloid leukemia (AML), providing a strong molecular rationale for targeting these enzymes to treat this disease. Although early phase clinical assessment indicated that treatment with HDAC inhibitors (HDACis) may be effective in t(8;21) AML patients, rigorous preclinical studies to identify the molecular and biological events that may determine therapeutic responses have not been performed. Using an AML mouse model driven by expression of AML1/ETO9a (A/E9a), we demonstrated that treatment of mice bearing t(8;21) AML with the HDACi panobinostat caused a robust antileukemic response that did not require functional p53 nor activation of conventional apoptotic pathways. Panobinostat triggered terminal myeloid differentiation via proteasomal degradation of A/E9a. Importantly, conditional A/E9a deletion phenocopied the effects of panobinostat and other HDACis, indicating that destabilization of A/E9a is critical for the antileukemic activity of these agents.

Topics: Animals; Antineoplastic Agents; Cell Differentiation; Cells, Cultured; Chromosomes, Human, Pair 21; Chromosomes, Human, Pair 8; Core Binding Factor Alpha 2 Subunit; Disease Models, Animal; Embryo, Mammalian; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Leukemia, Myeloid, Acute; Mice; Mice, Inbred C57BL; Mice, Transgenic; Oncogene Proteins, Fusion; Panobinostat; RUNX1 Translocation Partner 1 Protein; Translocation, Genetic

The bromodomain and extra-terminal (BET) protein family members, including BRD4, bind to acetylated lysines on histones and regulate the expression of important oncogenes, for example, c-MYC and BCL2. Here, we demonstrate the sensitizing effects of the histone hyperacetylation-inducing pan-histone deacetylase (HDAC) inhibitor panobinostat on human acute myelogenous leukemia (AML) blast progenitor cells (BPC) to the BET protein antagonist JQ1. Treatment with JQ1, but not its inactive enantiomer (R-JQ1), was highly lethal against AML BPCs expressing mutant NPM1c+ with or without coexpression of FLT3-ITD or AML expressing mixed lineage leukemia fusion oncoprotein. JQ1 treatment reduced binding of BRD4 and RNA polymerase II to the DNA of c-MYC and BCL2 and reduced their levels in the AML cells. Cotreatment with JQ1 and the HDAC inhibitor panobinostat synergistically induced apoptosis of the AML BPCs, but not of normal CD34(+) hematopoietic progenitor cells. This was associated with greater attenuation of c-MYC and BCL2, while increasing p21, BIM, and cleaved PARP levels in the AML BPCs. Cotreatment with JQ1 and panobinostat significantly improved the survival of the NOD/SCID mice engrafted with OCI-AML3 or MOLM13 cells (P < 0.01). These findings highlight cotreatment with a BRD4 antagonist and an HDAC inhibitor as a potentially efficacious therapy of AML.

Topics: Animals; Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Bcl-2-Like Protein 11; Cell Cycle; Cell Cycle Proteins; Cell Line, Tumor; Cluster Analysis; Disease Models, Animal; Drug Synergism; Female; Gene Expression Profiling; Gene Expression Regulation, Leukemic; Genes, bcl-2; Genes, myc; Hematopoietic Stem Cells; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Leukemia, Myeloid, Acute; Membrane Proteins; Mice; Neoplastic Stem Cells; Nuclear Proteins; Oncogene Proteins, Fusion; Panobinostat; Promoter Regions, Genetic; Protein Binding; Proto-Oncogene Proteins; RNA, Messenger; Transcription Factors; Xenograft Model Antitumor Assays

Inducing endoplasmic reticulum (ER) stress is a novel strategy used to treat malignancies. Inhibition of histone deacetylase (HDAC) 6 by the HDAC inhibitor panobinostat hinders the refolding of unfolded proteins by increasing the acetylation of heat shock protein 90. We investigated whether combining panobinostat with the proteasome inhibitor bortezomib would kill cancer cells effectively by inhibiting the degradation of these unfolded proteins, thereby causing ubiquitinated proteins to accumulate and induce ER stress.. Caki-1, ACHN, and 769-P cells were treated with panobinostat and/or bortezomib. Cell viability, clonogenicity, and induction of apoptosis were evaluated. The in vivo efficacy of the combination was evaluated using a murine subcutaneous xenograft model. The combination-induced ER stress and ubiquitinated protein accumulation were assessed.. The combination of panobinostat and bortezomib induced apoptosis and inhibited renal cancer growth synergistically (combination indexes <1). It also suppressed colony formation significantly (p <0.05). In a murine subcutaneous tumor model, a 10-day treatment was well tolerated and inhibited tumor growth significantly (p <0.05). Enhanced acetylation of the HDAC6 substrate alpha-tubulin was consistent with the suppression of HDAC6 activity by panobinostat, and the combination was shown to induce ER stress and ubiquitinated protein accumulation synergistically.. Panobinostat inhibits renal cancer growth by synergizing with bortezomib to induce ER stress and ubiquitinated protein accumulation. The current study provides a basis for testing the combination in patients with advanced renal cancer.

Topics: Acetylation; Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Boronic Acids; Bortezomib; Cell Line, Tumor; Disease Models, Animal; Drug Synergism; Endoplasmic Reticulum Stress; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Indoles; Kidney Neoplasms; Mice, Inbred BALB C; Panobinostat; Pyrazines; Ubiquitinated Proteins

The myeloproliferative neoplasm myelofibrosis is characterized by frequent deregulation of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling, and JAK inhibitors were shown to reduce splenomegaly and ameliorate disease-related symptoms. However, the mutant clone and bone marrow fibrosis persist in the majority of patients. Using preclinical models, we explored whether JAK and pan-deacetylase inhibitor combination yielded additional benefits.. The combination of the JAK1/2 inhibitor ruxolitinib and panobinostat was investigated using two different mouse models of JAK2(V617F)-driven disease. A Ba/F3 JAK2(V617F) cell-driven leukemic disease model was used to identify tolerated and efficacious doses. The drugs were then evaluated alone and in combination in a mouse model of myeloproliferative neoplasm-like disease based on transplantation of bone marrow transduced with a retrovirus expressing JAK2(V617F). Exposures were determined in blood and tissues, and phosphorylated STAT5 and acetylated histone H3 pharmacodynamic readouts were assessed in spleen and bone marrow. Histologic analysis was conducted on spleen and bone marrow, including staining of reticulin fibers in the latter organ.. The combination of ruxolitinib and panobinostat was found to have a more profound effect on splenomegaly, as well as on bone marrow and spleen histology, compared with either agent alone, and the analysis of pharmacodynamic readouts showed that ruxolitinib and panobinostat have nonoverlapping and complementary effects.. Combining JAK1/2 and pan-deacetylase inhibitors was fairly well tolerated and resulted in improved efficacy in mouse models of JAK2(V617F)-driven disease compared with the single agents. Thus, the combination of ruxolitinib and panobinostat may represent a promising novel therapeutic modality for myeloproliferative neoplasms.

Topics: Acetylation; Animals; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Cells; Disease Models, Animal; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Hydroxamic Acids; Indoles; Janus Kinase 1; Janus Kinase 2; Mice; Nitriles; Panobinostat; Polycythemia Vera; Primary Myelofibrosis; Pyrazoles; Pyrimidines; Reticulin; Spleen; Splenomegaly; STAT5 Transcription Factor; Thrombocytosis

Histone deacetylase inhibitors (HDACis) are a new class of compounds that induce acetylation of histone lysine tails in chromatin and modify gene expression. The Food & Drug Administration approved HDACi, Vorinostat, or suberoylanilide hydroxamic acid (SAHA), has been shown to inhibit tumor cell growth and the production of proinflammatory cytokines. In preclinical allogeneic transplant models, SAHA induces graft-versus-host disease (GVHD) amelioration in treated mice without impairing graft-versus-leukemia. LBH589 (Panobinostat), a structurally novel cinnamic hydroxamic acid class, is an HDACi more potent than SAHA. In the current work, we tested the hypothesis that LBH589 would be highly effective in the prevention of GVHD. Using mouse model of allogeneic bone marrow transplant (BMT), we unexpectedly found that treatment with LBH589 accelerated GVHD, in contrast to the treatment with SAHA that alleviated GVHD. Accelerated GVHD in the recipients treated with LBH589 was associated with elevated Th1 cytokines in recipient serum, enhanced CXCR3 expression on donor T cells, and T cell infiltration in the liver. The current study highlights the distinct effects of pan HDACi on allogeneic BMT and alerts that LBH589 (Panobinostat) could have an adverse effect on GVHD, and possibly on other inflammatory diseases.

Topics: Animals; Disease Models, Animal; Female; Graft vs Host Disease; Histone Deacetylase Inhibitors; Hydroxamic Acids; Indoles; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Panobinostat; T-Lymphocytes

Combinations of drug treatments based on bortezomib or lenalidomide plus steroids have resulted in very high response rates in multiple myeloma. However, most patients still relapse, indicating the need for novel combination partners to increase duration of response or to treat relapsed disease. We explored the antimyeloma activity of triple combinations of these well-established schemes with panobinostat, a novel deacetylase inhibitor with a multi-targeted profile.. The activity of these combinations was explored in vitro in cell lines by using MTT and annex-in V, ex vivo by flow cytometry, and in vivo using two different murine models of human myeloma: one bearing a subcutaneous plasmacytoma and another with a disseminated myeloma. Moreover, gene expression profiling and immunohistochemical studies were performed.. The addition of panobinostat (LBH589) to dexamethasone and either bortezomib or lenalidomide resulted in clear potentiation in multiple myeloma cell lines, freshly isolated plasma cells, and murine models of multiple myeloma. The quantification of the potency of these combinations by using the Chou-Talalay method showed synergistic combination indices for all of them. This effect derived from the deregulation of a cluster of genes that was completely different from the sum of genes affected by the single agents (895 and 1323 genes exclusively deregulated by panobinostat and dexamethasone plus bortezomib or lenalidomide, respectively). Functional experiments, such as annexin V staining, cell cycle analysis, and immunohistochemical studies also supported this potentiation. Anti-myeloma efficacy was confirmed in an extramedullary plasmacytoma model and a disseminated luciferized model, in which panobinostat also provided a marked benefit in bone disease.. The potent activity, together with the exclusive mechanistic profile, provides the rationale for the clinical evaluation of these drug combinations in multiple myeloma.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Boronic Acids; Bortezomib; Cell Line, Tumor; Cells, Cultured; Dexamethasone; Disease Models, Animal; Humans; Hydroxamic Acids; Indoles; Lenalidomide; Mice; Mice, SCID; Multiple Myeloma; Panobinostat; Pyrazines; Random Allocation; Thalidomide; Xenograft Model Antitumor Assays