Project description:Diffuse intrinsic pontine glioma (DIPG) is an aggressive and incurable childhood brain tumor for which new treatments are needed. A high throughput drug screen of 3600 pharmaceutical compounds found that anti-malarials, including quinacrine had potent activity against DIPG neurospheres. CBL0137 is a novel anti-cancer compound developed from quinacrine, which targets Facilitates Chromatin Transcription (FACT), a chromatin remodelling complex involved in transcription, replication, and DNA repair. We have found that CBL0137 displays profound cytotoxic activity against a panel of patient derived DIPG cultures, inhibiting cell proliferation and clonogenic potential, restoring tumor suppressor TP53 and Rb activity and inducing cell death through induction of apoptosis. Moreover, in an orthotopic model of DIPG, treatment with CBL0137 significantly extended animal survival. Histone mutations leading to the loss of histone trimethylation result in epigenetic dysregulation driving DIPG tumorigenesis. Treatment with CBL0137 targets this epigenetic defect, restoring both histone H3.3 acetylation and trimethylation and leading to tumor cell death. Combined epigenetic treatment with the histone deacetylase (HDAC) inhibitor panobinostat led to inhibition of the Rb/E2F1 pathway, and increased the enzymatic activity of enhancer of zeste homolog 2 (EZH2), leading to the restoration of H3K27 trimethylation. This combination therapy had synergistic activity against DIPG neurospheres with induction of apoptosis. Consistent with the in vitro results, the combination of CBL0137 and panobinostat significantly prolonged the survival of mice bearing DIPG orthografts suggesting a potential treatment strategy for DIPG.
Project description:Diffuse intrinsic pontine glioma (DIPG) is an aggressive and incurable childhood brain tumor for which new treatments are needed. A high throughput drug screen of 3600 pharmaceutical compounds found that anti-malarials, including quinacrine had potent activity against DIPG neurospheres. CBL0137 is a novel anti-cancer compound developed from quinacrine, which targets Facilitates Chromatin Transcription (FACT), a chromatin remodelling complex involved in transcription, replication, and DNA repair. We have found that CBL0137 displays profound cytotoxic activity against a panel of patient derived DIPG cultures, inhibiting cell proliferation and clonogenic potential, restoring tumor suppressor TP53 and Rb activity and inducing cell death through induction of apoptosis. Moreover, in an orthotopic model of DIPG, treatment with CBL0137 significantly extended animal survival. Histone mutations leading to the loss of histone trimethylation result in epigenetic dysregulation driving DIPG tumorigenesis. Treatment with CBL0137 targets this epigenetic defect, restoring both histone H3.3 acetylation and trimethylation and leading to tumor cell death. Combined epigenetic treatment with the histone deacetylase (HDAC) inhibitor panobinostat led to inhibition of the Rb/E2F1 pathway, and increased the enzymatic activity of enhancer of zeste homolog 2 (EZH2), leading to the restoration of H3K27 trimethylation. This combination therapy had synergistic activity against DIPG neurospheres with induction of apoptosis. Consistent with the in vitro results, the combination of CBL0137 and panobinostat significantly prolonged the survival of mice bearing DIPG orthografts suggesting a potential treatment strategy for DIPG.
Project description:The bromodomain inhibitor JQ1 and the histone deacetylase inhibitor panobinostat induce synergistic anticancer effects We analyzed whether JQ1 and panobinostat synergistically modulate gene expression Neuroblastoma SK-N-BE(2) cells were treated with vehicle control, 1 microM JQ1, 10 nM panobinostat, or combination of JQ1 and panobinostat for 6 hours, and subjected to differential gene expression studies with Affymetrix microarrays.
Project description:Purpose: We applied RNA sequencing technology for high-throughput analysis of transcriptional changes within human MM cell lines JJN3 and U266 due to individual and combination drug treatment. Methods: JJN3 and U266 cells were treated with pan-HDACi panbobinostat, DNMTi 5-Azacytidine, panobinostat+5-Azacytidine or NMP for 4h or 24h in triplicate and transcriptional changes assessed by RNAseq using Illumina HiSeq platform. Specifically, JJN3 cells were treated with 10nM panobinostat, 2.5µM 5-Azacytidine, panobinostat+5-Azacytidine (at given doses), or 10mM NMP. U266 cells were treated with 10nM panobinostat, 10µM 5-Azacytidine, panobinostat+5-Azacytidine (at given doses), or 10mM NMP. Results: We report unique and overlapping transcriptional signatures that lead to the induction of apoptosis in human MM cell lines in a cell-specific manner due to individual or combination treatments. Conclusions: A detailed analysis of differential transcriptional events in human MM cell lines due to HDACi, DNMTi, HDACi+DNMTi and NMP appear to define the molecular events leading to apoptosis and drug mechanism of action. We tested triplicate experiments at 4h and 24hr time points in JJN3 and U266 cell lines against vehicle control treated cells.
Project description:<p>Diffuse Intrinsic Pontine Glioma (DIPG) is a universally fatal childhood cancer. Here, we performed a chemical screen in patient-derived DIPG cell cultures along with RNAseq expression analysis and integrated computational modeling to identify potentially effective therapeutic strategies. Panobinostat, among the more promising agents identified, demonstrated efficacy in pontine orthotopic xenograft models of both H3K27M and histone WT DIPG. These data suggest the potential utility of specific drug combinations and provides evidence of in vivo treatment efficacy of the multi-histone deacetylase inhibitor panobinostat. We are depositing to dbGaP deep sequencing whole exome data for 22 patient tumor samples and 13 matched normals, along with RNAseq data for 12 patient tumor samples and 6 normal pediatric brain tissue samples. In addition, we are depositing 22 RNAseq samples from DIPG cell lines before and after panobinostat treatment.</p>
Project description:Diffuse midline gliomas (DMG) are a group of molecularly related malignancies occurring in midline structures of the childhood central nervous system, including thalamus, pons, and spinal cord. These cancers are characterized by high prevalence of the histone-3K27M mutation and are universally lethal, with median survival of only 9-11 months for pontine DMG (a.k.a. DIPG). In search of novel therapeutic options, we examined multiple cell models in sequential, quantitative high-throughput screens of approved and investigational drugs. This effort generated a total of 17,456 single-agent dose responses that inspired a subsequent series of HTS-enabled drug combination assessments encompassing a total of 8883 drug-drug examinations. Top combinations were validated across a panel of patient-derived cell lines representing the major DMG genotypes. In vivo testing in patient-derived xenograft models validated the combination of the multi-HDAC inhibitor panobinostat and the proteasome inhibitor marizomib as a promising therapeutic approach. Transcriptional and metabolomic surveys revealed substantial alterations to the cellular unfolded protein response and key metabolic processes following treatment with panobinostat and marizomib. Rescue of drug induced cytotoxicity and basal mitochondrial respiration with exogenous application of nicotinamide mononucleotide (NMN) or exacerbation of these phenotypes when blocking NAD+ production via NAMPT inhibition demonstrated that metabolic catastrophe drives the combination-induced cytotoxicity. This study represents the most comprehensive single-agent and combinatorial drug screen for DIPG reported to date and identifies concomitant HDAC and proteasome inhibition as a promising therapeutic strategy that underscores under-recognized metabolic vulnerabilities in DIPG. The combined screening outcomes represent a public resource for the DMG community.