bluuebunny/crossref_metadata_2025_split huggingface dataset:
DDDR-05. SPATIALLY RESOLVED DRUG SENSITIVITY PROFILING IN GLIOBLASTOMA
Authors: Buck Alicia , Lee Sohyon , Wegmann Rebekka , Mena Julien , Vasella Flavio , Friesen Julia , Regli Luca , Le Rhun Emilie , Zeitlberger Anna Maria , Neidert Marian Christoph , Tatari Nazanin , Hutter Gregor , Weller Michael , Snijder Berend , Weiss Tobias 
Published: November 2024

Abstract

BACKGROUND
Glioblastoma is the most common malignant primary brain tumor in adults, characterized by poor overall survival and an urgent need for more effective treatment strategies. Macroscopic heterogeneity, as observed through MR imaging, divides the tumor into distinct regions: a tumor-cell dense contrast-enhancing tumor core and a non-contrast-enhancing infiltration zone that appears hyperintense on T2/FLAIR imaging. The infiltration zone contains both infiltrating tumor cells and non-malignant cells from the local brain microenvironment. Although genomic and transcriptomic differences between the tumor core and the infiltration zone have been reported, functional differences, such as differential drug sensitivities, remain largely unknown.

METHODS
To investigate this, we collected region-specific glioblastoma patient tissue samples from both the contrast-enhancing tumor core and the non-contrast-enhancing but 5-aminolevulinic acid (5-ALA) fluorescent infiltration zone during surgery. Using pharmacoscopy, a microscopy-based single-cell drug screening platform, we assessed drug responses across regions and patients.

RESULTS
To determine whether drug responses within a single tumor region were more similar compared to responses across different regions we collected multiple tissue samples from each tumor region in seven patients. We identified region-specific drug responses for temozolomide and lomustine, among other drugs, in some of the patients. However, drug sensitivities were not consistent within the same region across different patients. Thus, across patients, the region-specific drug responses were obscured by patient heterogeneity. To address intra- and inter-tumor drug response heterogeneity, we developed a complementarity score based on region-specific drug response data of 60 drugs across 23 paired samples. The complementarity score identified promising drug combinations that demonstrated strong anti-tumor activity across tumor regions and patients.

CONCLUSIONS
Monotherapy approaches have largely failed in glioblastoma, despite extensive molecular profiling efforts aimed at identifying tumor-specific vulnerabilities. Identifying drug combinations that synergistically target the locoregional heterogeneity of glioblastoma may open up new avenues of personalized therapy.
DDDR-12. INHIBITION OF NOTCH PATHWAY VIA A NOVEL MONOCLONAL ANTIBODY PROLONGS SURVIVAL IN HIGH GRADE GLIOMA MODELS
Authors: Tosi Umberto , Ghita Greta , Saha Nayanendu , Mrad Zaki Abou , Giantini-Larsen Alexandra , Nikolov Dimitar , Yang Yanhong , Tabar Viviane 
Published: November 2024

Abstract
High grade gliomas (HGGs) have poor prognosis partially owing to a glioma-stem cell (GSC) population that escapes most therapeutic modalities. Inhibition of NOTCH signaling, necessary for GSC maintenance, has shown promise, however clinically limited by systemic (on-target, off-tumor) side effects. Thus, we develop a novel monoclonal antibody, 1H5, inhibitory against a disintegrin and metalloproteinase 10 (ADAM10), a protein responsible for NOTCH signaling initiation in tumor tissue, to treat HGGs. Patient-derived, glioma cell lines were treated with 1H5 to determine therapeutic IC50 and characterize downstream, NOTCH-related effectors. A patient-derived explant system, which best replicates the tumor microenvironment in vitro, was generated and treated. An orthotopic xenograft model (PDX) of HGG was created and treated with convection enhanced delivery (CED) of 1H5 to assess tumor volume and survival. We determined that ADAM10 is found in a majority of IDH-wildtype HGGs, but not on IDH-mutant HGGs or low-grade gliomas. 1H5 has nanomolar IC50 against a large library of HGG patient-derived cell lines, achieving cell death via NOTCH-signaling inhibition. In explants, treatment with 1H5 significant delays explant progression (p = 0.01), expansion (4.1-fold decrease, p = 0.007), and reduces the fraction of ADAM10+ cells (from 63.3% to 2.6%, p = 0.004), of replicating cells (from 10.0% to 0.9%, p = 0.006), and of GSCs (SOX2+ cells; from 65.8% to 12.8%, p = 0.06). In vivo, CED of 1H5 both slows down tumor growth compared to vehicle-treated controls (2.2-fold decrease in tumor volume, p = 0.03), and significantly prolongs survival (p = 0.01), without the development of significant side effects, through a reduction of replicating cells (p = 0.01) and SOX2+ GSCs (p &lt; 0.0001), in a dose-dependent fashion. In conclusion, 1H5 is efficacious against HGG preclinical models both in vitro and in vivo by targeting NOTCH signaling. This posits 1H5 as a new promising therapeutic worthy of expeditious clinical translation.
DDDR-14. IMPROVED ANTI-GLIOBLASTOMA EFFICACY BY BRG399, A NOVEL ORAL MICROTUBULE BINDING AGENT
Authors: Kendirli Mustafa Tansel , Nastke Maria-Dorothea , Aristizabal-Henao Juan , Khojasteh Abbas , Kiebish Michael , Chimmanamada Dinesh , Vishnudas Vivek , Recht Lawrence , Gesta Stephane 
Published: November 2024

Abstract
Glioblastoma (GBM) is a highly malignant form of brain tumor with a poor prognosis despite advances in treatments. Therapeutic resistance/relapse remains a significant challenge necessitating the development of novel approaches. BRG399 is a brain permeant, non P-gp substrate, microtubule-targeting agent that displays anti-cancer activity in vitro and in vivo. BRG399 was well tolerated in rat and dog toxicology studies. Anti-cancer activity (IC50) of BRG399 in in vitro models of GBM was assessed to have potency ranging from 42nm to 89nM in the 3 cell lines tested. Here, in vivo tumor activity of BRG399 was assessed in Sprague Dawley rats implanted with 3x105 C6 rat glioma cells into the right entorhinal cortex/subiculum region. 14 days post successful implantation tumors were assessed by MRI, rats were randomized to receive vehicle (2% Labrasol) or BRG399 (5, 10, 20 mg/kg groups) twice daily by oral gavage for 16 days, and MRIs were performed on survivors on days 31 and 45 post implantation. BRG399 administration resulted in a marked improvement in survival (from 7.7 ± 2.6 days to 25.5 ± 15.6 days, log-rank test, p:0.007) compared to controls. Six animals receiving BRG399 remained alive beyond day 60 of post-treatment initiation. To assess biodistribution of BRG399 in the brain, rats were implanted with C6 cells and tumor establishment assessed 12 days later by MRI. Animals were treated with vehicle or BRG399 (10, 20, 25 mg/kg) and plasma and brains were collected for bioanalytical assessment. Tissue single cell biodistribution was performed using TIMSTOF FLEX spatial OMICS. These results demonstrate a therapeutic effect of BRG399 on intracranial glioma-bearing rats with survival of the BRG399 treatment groups of strong statistical significance over the control group. Analysis of drug levels in plasma and brain will serve as guidance for dose and scheduling decisions for further therapeutic development.
DDDR-15. UTILIZING DEEP DOCKING AND ARTIFICIAL INTELLIGENCE FOR THE DISCOVERY OF NOVEL PARP1-SELECTIVE INHIBITORS FOR USE AGAINST BRAIN TUMORS
Authors: Truong Sarah , Ban Fuqiang , Smith Jason , Zhai Beibei , Ramos Louise , Marzban Mona , Ghaidi Fariba , Adomat Hans , Chen Xiaoqi , Langlands John , Brown Dennis , Bacha Jeffrey , Collins Colin , Cherkasov Artem , Daugaard Mads 
Published: November 2024

Abstract
Brain tumors, including primary brain tumors and central nervous system (CNS) metastases, remain among the most challenging malignancies to treat, with therapeutic options often limited by the inability of drugs to penetrate the blood-brain barrier. Poly(ADP-ribose) polymerase (PARP) is a key enzyme in DNA repair, and inhibition of PARP1 specifically drives synthetic lethality in BRCA-mutated disease. While they’ve achieved commercial success, first generation PARP inhibitors are limited in their utility as they cannot readily pass through the blood-brain barrier and have adverse side effects, likely driven by the collateral inhibition of PARP2. Development of a PARP1-selective, CNS penetrant inhibitor could reduce toxicity, while providing a new therapeutic option for brain tumors. Traditional drug discovery methods are time-consuming and costly, necessitating innovative approaches. Here, we describe the application of Deep Docking, an advanced artificial intelligence (AI) approach, to discover a novel, PARP1-selective inhibitor for use against brain tumors. Deep Docking utilizes deep learning to accelerate the prediction of the binding affinity of a large number of compounds to target proteins, streamlining the virtual screening process and allowing for rapid docking of billions of compounds against the PARP1 protein. Additionally, state-of-the-art generative algorithms and deep learning techniques for predicting drug-like properties such as metabolism, permeability, and safety profiles, can be combined to rapidly perform hit-to-lead optimization. We will present preliminary Deep Docking screening results from billions of compounds, identifying several with predicted high binding affinities for PARP-1. Validating in vitro and in vivo data, including PARP1 selectivity, metabolic stability, pharmacokinetic profile, CNS penetration and safety profile, will be described. Application of the Deep Docking AI platform is being used to significantly accelerate the discovery of a selective PARP-1 inhibitor for brain tumors. This approach will not only improve the efficiency of drug discovery but also enhance the specificity and efficacy of potential therapeutics.
DDDR-31. THE CHEMOTHERAPEUTIC ACTIVITY OF TEMOZOLOMIDE IS ANTAGONIZED BY ITS HYDROLYSIS PRODUCT, AIC
Authors: Sowers Mark L , Baljinnyam Tuvshintugs , Tang Hui , Herring Jason L , Hatch Sandra , Valdes Pablo , Zhang Kangling , Sowers Lawrence C 
Published: November 2024

Abstract
Temozolomide is the only FDA-approved drug that has demonstrated improved overall survival in patients with Glioblastoma. Despite the clinical impact it has had, overall survival today largely remains less than two years with current standard-of-care. Temozolomide is a prodrug that undergoes hydrolysis releasing 5-amino-4-imidazole carboxamide (AIC) before it can alkylate DNA. The DNA damage response invoked by TMZ depletes NAD+ levels. We present evidence from mass spectrometry LC-MS/MS studies that AIC released from TMZ can be aberrantly incorporated into the purine synthesis pathway, augmenting purine, and NAD+ synthesis and contributing to chemo- and radiation- resistance. The chemotherapeutic efficacy is therefore antagonized by its own hydrolysis product. TMZ analogs that do not generate AIC will likely have greater activity.
DDDR-37. OHSV AND RADIATION THERAPIES SENSITIZE GLIOBLASTOMA TO IGF1R-TARGETED THERAPY AND SYNERGIZE IN TRIPLE COMBINATION THERAPY
Authors: Miller Alexandra A , Noh Min Hye , Kang Jin Muk , Nguyen Grace , Huang Min Xin , Otani Yoshihiro , Nakashima Hiroshi , Chiocca E Antonio , Lee Tae Jin , Yoo Ji Young 
Published: November 2024

Abstract
Glioblastoma (GBM) continues to have a dismal prognosis despite remarkable advances in the field due to both tumor-intrinsic factors (i.e., IDH1 or EGFRvIII mutations) and extrinsic factors (i.e., relating to the tumor microenvironment (TME)), necessitating therapeutic innovation. Oncolytic herpes simplex virus-1 (oHSV) is an FDA-approved therapy that has shown promising results in clinical trials; however, therapeutic efficacy is limited to a small subset of patients. Thus, elucidating both the tumor-TME interplay and feedback/feedforward tumor-cell signaling in the context of viro-immunotherapy is essential in augmenting therapeutic outcomes. We recently discovered a novel mechanism of resistance to oHSVs, in which infection increases secretion of Insulin-like growth factor 2 (IGF2), activating the Insulin-like Growth Factor-1 Receptor (IGF1R). Upregulation of the IGF1R signaling pathway in GBM is correlated with poor prognosis and has been implicated in resistance to conventional therapies including radiotherapy (RTx). Herein, we further elucidate the impact of oHSVs on IGF1R activation, demonstrating a dose-dependent enhancement of downstream signaling. While IGF1R targeting therapies (e.g., OSI-966, Picropodophyllin (PPP)) have displayed limited efficacy in clinical trials, they significantly increased oHSV-induced cytotoxicity in all tested primary GBM cells compared to either agent alone in vitro and in vivo, resulting in a dose-dependent increase in PARP and caspase 3 activity by western blot and immunohistochemistry. We further found that RTx-induced IGF1 secretion and subsequent IGF1R activation were enhanced when combined with oHSV treatment. Triple combination therapy with oHSV, IGF1R inhibition, and RTx significantly increased tumor cell killing in vitro and improved survival of orthotopic GBM tumor-bearing mice. Collectively, our study provides preclinical evidence of enhanced therapeutic efficacy of oHSVs and RTx in combination with IGF1R blockade, supporting future use of IGF1R inhibitors in combination with the standard of care and FDA-approved oHSV therapies in patients with GBM.
DDDR-39. PI3 KINASE AND CHECKPOINT INHIBITION: A POTENTIALLY NOVEL THERAPEUTIC STRATEGY FOR GLIOBLASTOMA (GBM)
Authors: Jalali Ali , Siddik Abu Bakar , Yu Kwanhu , Tobin Richard P , Hay Charles E , Aminkeng Folefac , Fonkem Ekokobe , Newell-Rogers M Karen 
Published: November 2024

Abstract
Glioblastoma is the most common and aggressive malignant brain tumor with a median survival of less than 2 years, highlighting the need for more effective therapeutics. Dual pathway synergism between PI3K inhibitors and check-point inhibitors is a promising therapeutic avenue that has not been explored. Based on this possibility, we hypothesized that the combination of PI3K and checkpoint inhibitors will improve survival in our native glioblastoma mouse model. Treatment with GCT-007, a small molecule PI3K inhibitor, induces growth arrest of GBM cells that is accompanied by increases in the cell surface expression of molecules targeted by the immune system and immunotherapy drugs, including MHC Class II and PD-L1. Treatment of mouse GL261 and human U251 GBM cell lines with GCT-007 caused growth arrest, increased the cell surface expression of PD-L1 and MHC class II, and synergized with radiation to cause growth arrest and cell death. We compared GCT-007 to Paxalisib in our in vitro studies and observed that GCT-007 outperformed Paxalisib at increasing MHC class II and PD-L1 expression on the tumor cells at equivalent doses. We then performed in vivo animal studies using our native mouse GBM model. We treated mice orally with GCT-007 and observed a significantly prolonged survival compared to placebo. Mice treated with anti-PD1 resulted in a sexually dimorphic response consisting of prolonged remission of all female mice, now surviving beyond 1 year, but no improvement in the survival of male mice compared to placebo. Adding GCT-007 to anti-PD1 did not alter the prolonged remission outcome in female mice, it did result in prolonged remission of 25% of the male mice, now beyond 1 year. In conclusion, these results indicate that GCT-007 treatment alone improves survival in our native GBM mouse model and it may also improve the response to immune checkpoint inhibitor therapy in at least a fraction of GBM tumors. These data warrant further investigation as a potentially novel therapeutic approach to GBM.
DDDR-40. TARGETING BCL-XL WITH MIRZOTAMAB CLETUZOCLAX (ABBV-155) AND STANDARD OF CARE THERAPIES OVERCOMES APOPTOTIC RESISTANCE IN GLIOBLASTOMA
Authors: Fernandez Elizabeth , Mai Wilson , Young Pauline , Young William , Rodriguez Fausto , Souers Andrew , Cloughesy Timothy , Nathanson David 
Published: November 2024

Abstract
Conventional GBM therapies (e.g., temozolomide (TMZ), irradiation (IR)) transiently halt tumor growth of glioblastoma (GBM) but fail to induce apoptosis, inevitably leading to disease progression and poor patient survival. Targeting apoptotic blocks with BH3 mimetics can be an efficacious strategy to trigger apoptosis; however, these therapies can prevent high exposures in patients due to on-target, off-tumor toxicity in normal tissues. Mirzotamab Cletuzoclax (ABBV-155) is a first-in-class antibody-drug conjugate (ADC) that is specific for the highly expressed cell surface protein B7-H3 (CD276) and delivers a selective and potent BCL-XL inhibitor warhead. Here we identified that both TMZ and IR leave p53 WT GBM tumors exclusively dependent on the apoptotic block, BCL-XL, for survival. ABBV-155 negated the BCL-XL apoptotic block in both cell culture and orthotopic xenograft GBM models. Consequently, ABBV-155 combined with TMZ or IR initiates apoptosis and is synergistically lethal in GBM cells. Moreover, these combinations decrease tumor burden and extend survival in patient derived orthotopic xenografts. Taken together, these results demonstrate that the combination of DNA damaging therapy and ABBV-155 can have a synergistic anti-tumor impact in p53 WT GBM.
DDDR-43. ERAS-801 IS A SELECTIVE BRAIN-PENETRANT EGFR INHIBITOR WITH IMPROVED ACTIVITY AGAINST EGFR EXTRACELLULAR DOMAIN-MUTANT GLIOBLASTOMA
Authors: Okobi Quincy , Cadet Dimitri , Urner Lorenz , Jung Michael , Cloughesy Timothy , Nathanson David 
Published: November 2024

Abstract
Epidermal growth factor receptor (EGFR) is a driver of nearly 50% of glioblastoma (GBM), yet EGFR inhibitors have failed in GBM (e.g., erlotinib, lapatinib, neratinib, gefitinib, and afatinib) due to poor CNS penetration and/or an inability to inhibit EGFR in its wildtype and extracellular domain (ECD) mutated forms (e.g., EGFRvIII). Here we describe ERAS-801, a reversible and selective EGFR tyrosine kinase inhibitor with unique binding properties that enable potent activity for amplified and ECD mutant EGFR. ERAS-801 demonstrated the highest nonclinical CNS penetration out of all tested EGFR inhibitor comparators. Accordingly, relative to other EGFR inhibitors tested in GBM trials (e.g., erlotinib, lapatinib, and osimertinib), ERAS-801 showed superior survival benefit in EGFR altered orthotopic PDX models. Finally, further characterization of ERAS-801 in a preclinical trial of glioma orthotopic PDX models that capture the molecular heterogeneity of GBM, ERAS-801 demonstrated a significant survival benefit at a 25 mg/kg QD dose in the vast majority of EGFR-driven orthotopic GBM PDX models, with FDG-PET imaging serving as a non-invasive biomarker of response. Based on these nonclinical data, ERAS-801 is currently under clinical investigation for GBM.
DDDR-44. REPURPOSING SSRI/SNRI TARGETING NEUROTRANSMITTER SIGNALING TO OVERCOME RESISTANCE TO CDK9 INHIBITORS IN DIFFUSE MIDLINE GLIOMA
Authors: Murdaugh Rebecca L , Eberl Brittany R , Richard Rosemary U , Tremblay Jack , Dei-Ampeh Alfred , Anastas Jamie N 
Published: November 2024

Abstract
Diffuse midline glioma (DMG) is a subset of aggressive brain tumors with few effective therapies. Cyclin-dependent kinase 9 (CDK9i) inhibitors such as zotiraciclib (ZTR) are in clinical trials for glioma, but CDK9i treatment alone may be ineffective due to the development of resistance. To identify CDK9i resistance mechanisms, we analyzed the transcriptomes of DMG xenograft tumors after three weeks of treatment with ZTR, which revealed that transcripts encoding synaptic signaling regulators such as glutamate receptors were overexpressed in surviving cells, suggesting that altered regulation of synaptic signaling may mediate CDK9i resistance. We also performed drug synergy screens using a library of FDA-approved and bioactive compounds and found that drugs that modulate neurotransmitter signaling, such as SSRIs and SNRIs (selective serotonin and serotonin/norepinephrine reuptake inhibitors), increased DMG sensitivity to an IC25 dose of ZTR. Follow-up studies confirm that combinations of structurally distinct CDK9i (ZTR, AZD4573) and SSRI/SNRI (sertraline, duloxetine) synergistically reduce DMG growth in neurospheres by BLISS analysis and show that co-treatment with CDK9i and SSRI/SNRI strongly induces the apoptotic marker cleaved caspase 3 and reduces the CDK9 target phos-Pol2Ser2. Additional phospho-proteomic analyses identified differentially phosphorylated proteins following CDK9i+SSRI treatment, including chromatin regulators, Pol2 elongation factors, and splicing regulators. Further RNAseq studies reveal that CDK9i+SSRI treatment resulted in more robust transcriptional changes than either drug alone, including the downregulation of transcripts associated with ZTR resistance such as GRIA3/4, and SYT12. These observations suggest that CDK9i +SSRI/SNRI drug combinations may overcome some of the transcriptional changes underlying CDK9i resistance. Finally, preclinical studies show that co-treatment with low doses of AZD4573 and sertraline reduces the growth of orthotopic DMG xenografts and prolongs overall survival. Taken together, these data suggest that SSRI/SNRI and CDK9i might be used in combination to synergistically reduce DMG growth and overcome CDK9i resistance.
DDDR-47. TARGETING HTR2B SUPPRESSES NON-FUNCTIONING PITUITARY ADENOMA GROWTH AND SENSITIZES CABERGOLINE TREATMENT VIAINHIBITING GΑQ/PLC/PKCΓ/STAT3 AXIS
Authors: Lin Shaojianlin , Wang Liangbo , Han Changxi , Dai Yuting , Xue Li , Wu Zhe Bao 
Published: November 2024

Abstract

BACKGROUND
Managing non-functioning pituitary adenomas (NFPAs) is difficult due to limited drug treatments. Cabergoline’s (CAB) effectiveness for NFPAs is debated. This study explores the role of HTR2B in NFPAs and its therapeutic potential.

METHODS
We conducted screening of bulk RNA-sequencing data to analyze HTR2B expression levels in NFPA samples. In vitro and in vivo experiments were performed to evaluate the effects of HTR2B modulation on tumor growth and cell cycle regulation. Mechanistic insights into the HTR2B-mediated signaling pathway were elucidated using pharmacological inhibitors and molecular interaction assays.

RESULTS
Elevated HTR2B expression was detected in NFPA samples, which was associated with increased tumor survival. Inhibition of HTR2B activity resulted in the suppression of tumor growth through modulation of the G2M cell cycle. The inhibition of HTR2B with PRX-08066 was found to block STAT3 phosphorylation and nuclear translocation by interfering with the Gαq/PLC/PKC pathway. A direct interaction between PKC-γ and STAT3 was critical for STAT3 activation. CAB was shown to activate pSTAT3 via HTR2B, reducing its therapeutic potential. However, the combination of an HTR2B antagonist with CAB significantly inhibited tumor cell proliferation in HTR2B-expressing pituitary tumor cell lines, a xenografted pituitary tumor model, and patient-derived samples. Analysis of patient-derived data indicated that a distinct molecular pattern characterized by upregulated HTR2B/PKC-γ and downregulated BTG2/GADD45A may benefit from combination treatment with CAB and PRX-08066.