bluuebunny/crossref_metadata_2025_split huggingface dataset:
EXTH-46. TESTING PRECISION GENOMICS-GUIDED THERAPY IN A MODEL OF ANAPLASTIC PLEOMORPHIC XANTHOASTROCYTOMA: DUAL INHIBITION OF CDK4/6 AND MEK
Authors: Koenig Jenna , Saadatzadeh M Reza , Bailey Barbara J , Pandya Pankita H , Dobrota Erika A , Coy Kathryn , Kennedy Felicia M , Sinn Anthony L , Tailor Jignesh K , Angus Steven P , Damayanti Nur P , Pollok Karen E 
Published: November 2024

Abstract
Typical survival for pediatric high-grade gliomas remains less than 18 months despite recent improved understanding of the molecular drivers of these tumors. Hyperactivating MAPK and CDK4/6 pathway mutations are common and targetable alterations implicated in tumorigenesis and malignant transformation in pediatric glioma. We have established and characterized a novel patient-derived xenograft (PDX) model, RHT128, from a pediatric patient diagnosed with the high-grade glioma anaplastic pleomorphic xanthoastrocytoma (APXA). The molecular landscape of PDX RHT128 exhibits molecular fidelity to the patient’s tumor. Clinical precision genomics analysis of the tumor revealed a novel BRAF chromosomal rearrangement and CDKN2A/B deletion. Based on this molecular signature, the patient was treated with MEK inhibitor trametinib as a monotherapy and, following progression of disease, with CDK4/6 inhibitor ribociclib. However, the tumor continued to progress. In this study our objective is to simultaneously target the CDK4/6 and MAPK pathways in RHT128 and determine to what extent this combination therapy minimizes emergence of therapeutic resistance. Single-agent efficacy assessments in a subcutaneous RHT128 model, showing significant dose-dependent reduction in tumor volume after treatment with abemaciclib (p&lt;0.05), palbociclib (p&lt;0.01), and the blood-brain barrier-permeable MEK inhibitor mirdametinib (p&lt;0.0001). Analysis of the global kinome in CDK4/6 inhibitor-treated PDX tissues compared to vehicle treatment using multiplexed-inhibitor bead chromatography–mass spectrometry demonstrated effective inhibition of CDK4/6. Moreover, this analysis revealed dose-dependent alterations in the MAPK and PI3K pathways and modulation of critical neurotransmitter pathways in treated tissues. Future studies will explore efficacy of these MEK and CDK4/6 inhibitors in combination and in our BRAF wild-type and BRAF V600E variant APXA models to gain further mechanistic insights. The pervasiveness of alterations to the MAPK and CDK4/6 pathways in pediatric gliomas make this approach promising for further study in a broader range of these deadly tumors.
EXTH-56. INVESTIGATING THE EFFECTS OF INDIRUBINS IN PEDIATRIC DIFFUSE HIGH GRADE GLIOMA MODELS
Authors: Clark Jasmine , Lawler Sean , Jimenez-Macias Jorge , Vaughn-Beaucaire Philippa , Zhang Shengliang , El-Deiry Wafik , Lulla Rishi 
Published: November 2024

Abstract
Diffuse midline glioma (DMG) is a highly invasive and fatal pediatric brain tumor that arises from glial cells within the pons of the brainstem. Despite focal radiation treatment, DMG continues to have a poor prognosis, with a median survival of less than 10 months. A significant challenge in treating DMG is the blood-brain barrier (BBB), which tightly restricts access to therapeutic agents, preventing drugs from reaching the brain at effective concentrations. Previous studies from the Lawler lab have shown that the indirubin derivative 6-bromoindirubin-3′-acetoxime (BIO-acetoxime/BIA) has anti-invasive properties and can enhance survival in glioblastoma xenograft models. We investigated the effects of BIA on pediatric glioma models using various assays. In an in vitro scratch migration assay, BIA significantly slowed cell migration at a concentration of 1µM in pediatric glioma cells over 72 hours. Additionally, BIA was shown to modulate tumor vasculature and improve drug delivery to tumors by targeting tight junctions in tumor-associated endothelium. BIA treatment increased dextran uptake into 3D BBB models and lowered endothelial cell permeability in vitro by reducing the expression of tight junction proteins, as shown by staining and a decrease in TEER values. Furthermore, BIA’s anti-angiogenic effects were demonstrated through staining, showing significant alterations in angiogenesis-related protein expression. To assess potential synergistic interactions, a drug screen was performed on a panel of pediatric glioma cell lines identifying several FDA-approved drugs that combine well with BIA. Drugs identified in the screen are currently under investigation. Our hypothesis is that BIA could be an effective therapeutic agent for DMG by targeting tumor invasion, angiogenesis, and improving drug potency and delivery through modulation of endothelial cell tight junctions. Future studies will focus on elucidating the underlying mechanisms and developing drug formulations for in vivo studies to assess the translational potential of this approach.
EXTH-61. TOWARDS A QUANTUM THERAPY FOR GLIOBLASTOMA: A NEW THERAPEUTIC PARADIGM IN MEDICINE
Authors: Jain Akhil , Gosling Jonathan , Liu Shaochuang , Wang Haowei , Stone Eloise , Chakraborty Sajib , Jayaraman Padma-Sheela , Smith Stuart , Amabilino David B , Fromhold Mark , Long Yi-Tao , Pérez-García Lluïsa , Turyanska Lyudmila , Campora Simona , Cicero Alessandra Lo , Ghersi Giulio , Rahman Ruman , Rawson Frankie 
Published: November 2024

Abstract

BACKGROUND
A cell operates as an interconnected bioelectrical circuit, utilising electron transfer processes for intracellular communication, with cytochrome c (Cyt c) playing a pivotal role. The redox processes of Cyt c, occurring via electron tunnelling, are essential for its translocation into the cytosol and modulation of its conformation to bind apoptotic protease activating factor 1. This highlights the need for novel technologies capable of interacting with these processes at the atomic scale to control downstream effects and induce apoptosis in cancer cells.

METHODS
We demonstrate that ‘bio-nanoantennae’, when supplied with an electrical current, enable quantum biological tunnelling for electron transfer (QBET) and facilitate cellular apoptosis in patient-derived IDH wild-type glioblastoma from both the infiltrative tumour margin and proliferative core. The bio-nanoantennae were constructed from gold nanoparticles functionalised with reduced Cyt c and zinc porphyrin as a redox couple.

RESULTS
Electrical polarisation of these bio-nanoantennae via resonant alternating currents in preclinical glioblastoma cells led to decreased metabolic activity and reduced cell viability by oxidizing Cyt c, thus inducing cellular stress. No significant effect was observed in healthy human astrocyte counterparts. The cytosol localised bio-nanoantennae induced differential gene expression related to ion channels, apoptosis, cancer proliferation and tumour suppression upon activation, in tumour relative to astrocyte cell populations. The bio-nanoantennae were also tested in 3D glioblastoma spheroid models, showing similar effects, and in vivo studies demonstrated a significant reduction in glioblastoma xenograft tumour size.

CONCLUSION
We propose that bio-nanoantennae modulate the redox state of Cyt c under an electrical field through QBET. To validate this, we investigated the tunnel junction energy and plasmon resonance scattering, and developed a mathematical model to explain the system’s behaviour. This innovative wireless electrical–molecular nanodevice, capable of inducing cancer cell apoptosis, paves the way for further applications of quantum signalling as a new (non-pharmacological) therapeutic paradigm.
EXTH-62. FOCAL ADHESION KINASE (FAK) IN CHROMOSOME 8 GAIN-ASSOCIATED MALIGNANT PERIPHERAL NERVE SHEATH TUMORS (MPNST)
Authors: Wang Guangfeng , Borcherding Dana , Oztosun Gorkem , Zhang Xiaochun , Yang Liuzhan , Gannu Trisha , Hirbe Angela 
Published: November 2024

Abstract

OBJECTIVES
Malignant peripheral nerve sheath tumors (MPNST) are aggressive sarcomas often associated with Neurofibromatosis type 1 (NF1), a genetic syndrome driven by overactivation of the RAS pathway. MEK inhibitors (MEKi) target downstream components of the RAS pathway and have been approved for NF1 patients with plexiform neurofibromas (PN). However, MPNST often develop resistance to MEKi. Our lab recently discovered the critical role of chromosome 8 (Chr8) genes in MPNST. The Chr8 gene, protein tyrosine kinase 2 (PTK2), also known as focal adhesion kinase (FAK) is overexpressed in multiple cancers, suggesting its importance in tumor progression. In this study, we aim to evaluate FAK as a therapeutic target for MPNST and investigate the FAKi and RAF/MEKi combination.

METHODS
A CRISPR gRNA screen was used to identify Chr8 genes involved in MPNST survival. The effect of FAK shRNA knockdown and a FAK inhibitor (FAKi), alone or combined with a MEKi, in MPNST cells was assessed using IncuCyte proliferation assays and multiple murine models.

RESULTS
The CRISPR gRNA screen identified 57 genes on Chr8 important for MPNST cell survival, including PTK2/FAK. Knockdown of FAK by shRNA in MPNST inhibited cell proliferation in vitro and reduced tumorigenesis in vivo. Consistently, the FAKi defactinib significantly inhibited the proliferation of MPNST (IC50-values: 1.72-4.65μM). Moreover, the defactinib/avutometinib combination was synergistic in vitro and the combination of FAKi with RAF/MEKi reduced tumor growth more that either drug alone in Chr8-gain MPNST PDX models. Avutometinib induced compensatory activation of FAK, while defactinib/avutometinib combination decreased phosphorylation of FAK, ERK1/2 and STAT3, and augmented cleavage of Caspase-3 and PARP-1, shown using the WES protein simple system.

CONCLUSION
These results demonstrate the potential therapeutic efficacy of FAK inhibitors, both alone and in combination with RAF/MEKi, for the treatment of MPNST.
EXTH-64. MECHANISMS OF MITOCHONDRIAL COMPLEX-I SENSITIVITY IN GBM
Authors: Dasgupta Biplab , Horchar Matthew , Gawali Mruniya , Desai Pankaj , Choi Kwangmin , D’Alessandro Angelo 
Published: November 2024

Abstract
The biguanide metformin that is widely used for the management of Type 2 diabetes is being evaluated as an anti-neoplastic agent in cancer trials including GBM (NCT02780024, NCT03243851). The mechanisms of action of metformin as an anti-neoplastic agent is still being investigated, but recent studies have unequivocally demonstrated that its therapeutic effects in tumor cell growth and signaling are dependent on inhibition of mitochondrial complex I. Based on the success of metformin in combination therapy in some cancers, new generation of mitochondrial complex I inhibitors (MCI-i) such as IM156, IACS-010759, are currently under investigation. Diffusion of metformin across the plasma membrane occurs slowly. Its entry is facilitated by two transporters OCT1 and OCT2 that are not well expressed outside the liver and kidney. This presents a problem due to its lack of accumulation in other tissues at therapeutic concentrations. Therefore, identification of tumor subtypes that respond better to lower concentrations of metformin may be leveraged for targeted metformin therapy. Metformin GBM trials may be unsatisfactory since there are no molecular markers to distinguish metformin responders from non-responders. Identification of molecular markers may greatly improve metformin and other MCI-i-based therapy in GBM. By examining TCGA data and experimental analysis, we have identified that PDHA, that catalyzes pyruvate to acetyl Co-A, is a predictive molecular marker for MCI-i sensitivity in GBM and potentially beyond GBM. PDHA expression varies widely in patient tumors, potentially due to differential methylation. We are performing joint pathway analysis by examining differentially expressed genes and stable isotope tracing studies to determine distinct metabolic signatures in the two subsets of GBM. We are also performing Classification And Regression Tree (CART) analysis on a cohort of sixty primary GBM lines and tissues to predict if PDHA expression provides a binary outcome for MCI-i sensitivity.
EXTH-66. ONCOLYTIC ADENOVIRAL INFECTION SYNERGIZES WITH IMMUNE CHECKPOINT INHIBITION TO MEDIATE INTRACRANIAL TUMOR CONTROL IN DISPARATE MODELS OF MELANOMA BRAIN METASTASES
Authors: Du Yi , Singh Sanjay , Tawbi Hussein , Davies Mike , Lang Fred , Gomez-Manzano Candelaria , Fueyo Juan , Alvarez-Breckenridge Christopher 
Published: November 2024

Abstract
Amongst all solid cancers, melanoma brain metastases (MBM) have the highest likelihood of metastasizing to the brain. The emergence of immune checkpoint inhibitors (ICI) for metastatic melanoma have demonstrated increasingly promising results; however, intracranial progression remains a challenging obstacle. Oncolytic viral (OV) therapy leverages tumor cell replication machinery to selectively replicate and kill tumor cells and promote anti-tumor immunity. We propose this OV strategy can be applied to MBM through direct tumor infection that simultaneously sustains a distant antitumor immune response. To counteract immunosuppressive features of the tumor microenvironment (TME), a third-generation oncolytic adenovirus (Delta-24-RGDOX) has been developed which expresses the immune stimulatory OX40 ligand (OX40L). We quantified the cytotoxic capacity of Delta-24-RGDOX and its ability to achieve immunogenic cell death (ICD) in vitro along with cerebral organoid co-culture models. Additionally, we used a series of syngeneic murine melanoma models to explore local and systemic antitumor immunity following Delta-24-RGDOX infection. Delta-24-RGDOX inoculation achieved viral infection, OX40L cell surface expression, tumor cell cytotoxicity, and ICD in vitro. Viral oncolysis was recapitulated in a cerebral organoid melanoma co-culture model with concomitant alterations in microglia activation and detection of viral transcripts within microglia using single cell RNA sequencing, suggesting a viral-clearing role of microglia within the TME. Local tumor clearance was achieved in orthotopic intracranial models following direct intracranial viral inoculation alone, and in combination with ICI. Lastly, we demonstrated improvement in overall survival in a synchronous subcutaneous/intracranial B16F10 model where the subcutaneous tumor was treated with Delta-24-RGDOX in combination with ICI. In summary, Delta-24-RGDOX achieves viral infection, oncolysis, and ICD following infection of melanoma cell lines. These findings translated in multiple in vivo models including immune cell activation and systemic antitumor immunity against uninfected MBM. Future studies are needed to explore the role of immune cell trafficking, myeloid cell modulation, T cell priming, and clonal expansion withing locally infected and the distant melanoma TME.
EXTH-67. ONCOLYTIC ADENOVIRAL INFECTION OF CHORDOMA ACHIEVES TREATMENT EFFICACY THROUGH IMMUNOGENIC CELL DEATH AND TUMOR MICROENVIRONMENT ALTERATION
Authors: Wu Xizi , Ledbetter Daniel , de Almeida Romulo Andrade , Singh Sanjay , Conley Anthony , Wang Wein-Lien , Lazar Alex , Lang Fred , Gomez-Manzano Candelaria , Fueyo Juan , Alvarez-Breckenridge Christopher 
Published: November 2024

Abstract
Chordomas are locally aggressive neoplasms of the axial skeleton with recurrence rates approaching 40%. Moreover, recurrent chordomas are nearly impossible to eradicate—highlighting an unmet clinical need. Immunotherapeutic approaches, such as immune checkpoint inhibition (ICI), has been a successful tool to modulate the tumor microenvironment (TME) towards a pro-inflammatory, antitumor state. There is emerging interest in exploring immunomodulatory agents for chordomas. Oncolytic viral (OV) therapy uses genetically modified viruses which selectively replicate in tumor cells, mediate tumor cell lysis, and initiate a pro-inflammatory response within the infected TME. These findings suggest that OV therapy may be a clinically relevant, novel immunotherapeutic approach for chordoma. Using the replicating oncolytic adenovirus Delta-24-RGD, we investigate the efficacy of chordoma treatment using in vitro approaches, ex vivo bone scaffolds, and in vivo murine models. Additionally, we explore the underlying mechanism of OV cytotoxicity, immunogenic cell death, Brachyury modulation, and reshaping of the TME towards a pro-inflammatory state. Across a panel of human chordoma cell lines, Delta-24-RGD achieved viral infectivity, oncolysis and immunogenic cell death. This treatment response was similarly demonstrated in chordoma cultured in bone scaffold models. Delta-24-RGD infection was associated with concomitant Brachyury downregulation within both infected and uninfected chordoma cells in vitro, suggesting a pleiotropic effect following oncolytic viral infection. In vivo models of CH22 chordoma treated with Delta-24-RGD demonstrated shrinkage in tumor volume and enhanced overall survival. Utilizing a human chordoma tissue microarray, the immunosuppressive macrophage marker CD163 was associated with shortened recurrence free survival. Using macrophage/chordoma co-culture, Delta-24-RGD infection achieved a reduction in macrophage expression of CD163. Taken together, Delta-24-RGD demonstrated efficacy in multiple models of chordoma including mice bearing CH22 tumors. The chordoma TME is associated with clinical outcomes and Delta-24-RGD infection reverses a deleterious immunosuppressive immune profile. These studies provide a framework for future clinical trial implementation for patients with metastatic or recurrent chordoma.
EXTH-71. A MECHANISTIC INVESTIGATION INTO AUGER THERAPY: 2-DIMENSIONAL THIN-FILMS TO CHARACTERIZE THERAPEUTIC RANGEIN VITRO
Authors: Al-Husseini Jacob , Upreti Meenakshi , Ha Joseph , Moats Rex , Koos David , Fong Ethan , Baker Clark , Spindler Archie , Johal Malkiat , Chiarelli Peter 
Published: November 2024

Abstract
Metallic nanoparticles can improve the accuracy and effectiveness of conventional radiotherapy in the treatment of solid tumors through a light-matter interaction known as the Auger effect. In this work, we present the assembly of an iron oxide (Fe3O4) nanoparticle (NPs) layer within a biocompatible polyelectrolyte film using ionic self-assembly to enable the spatial separation of NPs from their target cells. Films exhibited uniform nanoparticle coverage as well as strong stability in cell culture conditions. To investigate the applicability of NMDR with non-internalized NPs, conditions with (NP-PEM) and without (PEM) embedded nanoparticles were used to evaluate the therapeutic effect of physically separated nanoparticles on cells cultured on the film surface via a measure of intracellular reactive oxygen (ROS) generation and histone phosphorylation (yH2AX) after irradiation from a 137Cesium source. Cells cultured on NP-PEM demonstrated a 78.4% increase in ROS generation when compared to cells cultured on PEM films. When adjusting for cell count, NP-PEM films induce 70.5% greater ROS generation. In investigating nanoparticle-mediated deposition of radiation (NMDR), these films allow for the determination of the extent of the therapeutic effect when NPs are not internalized into their targeted cells, potentially providing indications with respect to off-target effects. Cells were irradiated on films with nanoparticle distances from 25.9 nm to 97.5 nm to interrogate the NMDR effect size at a range of distances. yH2AX phosphorylation exhibited an exponential decay until 69.8 nm, where there was no difference when compared to nanoparticle-free films. This work highlights the ability of iron oxide NPs to deliver NMDR at a known, quantifiable distance, providing insights for further translational applications.
EXTH-73. TARGETING THE CELL ADHESION CLUSTER OF DIFFERENTIATION 44 TRANSMEMBRANE GLYCOPROTEIN SENSITIZES CRANIOPHARYNGIOMAS TO IMMUNOTHERAPY
Authors: Lujan Arturo , Chakrabarti Jayati , Eschbacher Jennifer , Zada Gabriel , Kim Albert , Little Andrew , Santagata Sandro , Zavros Yana 
Published: November 2024

Abstract

BACKGROUND
Craniopharyngiomas are categorized as an adamantinomatous craniopharyngioma (ACP) or papillary craniopharyngioma (PCP) subtype with distinct histological, pathological and genetic differences. Studies propose the potential therapeutic benefit of targeting PD-L1 and/or PD-1 in both ACP and PCP subtypes using immune checkpoint inhibitors (ICI). The alternative mRNA splice variant of CD44, CD44v9, is expressed on cancer stem cells and plays multiple key roles including drug resistance and tumor cell invasiveness. CD44 positively regulates PD-L1, but the role of this transmembrane glycoprotein in craniopharyngioma tumorigenesis is unknown. Objectives: To replicate the complexity of the craniopharyngioma tumor microenvironment (TME) by developing a novel patient tissue-generated craniopharyngioma in vitro organoid preclinical model for the development of therapeutic strategies. Approach: NanoString CosMx™ Spatial Molecular Imager (SMI) was performed using FFPE tissue sections prepared from patient craniopharyngiomas. Quantification of PD-L1, and stem cell transmembrane glycoproteins CD44v9 and TROP2 was performed using multiplex immunofluorescence (MxIF). Craniopharyngioma patient-derived organoids (CranioPDOs) were generated and co-cultured with autologous immune cells (IMM) generated from patient peripheral blood mononuclear cells. CranioPDO/IMM co-cultures were used to predict the potential therapeutic benefit in response to tyrosine kinase inhibitor cabozantinib (Cabo) plus pembrolizumab (Pembro) or atezolizumab (Atezo) combinatorial therapy.

RESULTS
SMI analysis showed expression of CD44 and TROP2 positive cells, cancer-associated fibroblasts and myeloid-derived suppressor cells (MDSCs) consistent with the staining pattern of PD-L1. MxIF of matched tissues showed expression of CD44v9 and TROP2 within the same CD44 positive spatially mapped cell populations. Combinatorial treatment of CranioPDO/IMM co-cultures with Cabo plus Pembro or Atezo led to depletion of MDSCs correlating with decreased expression of CD44v9 and a significant increase in cytotoxic T lymphocyte proliferation and tumor cell death.

CONCLUSION
Our preclinical in vitro organoid data support the potential therapeutic benefit of ICI in combination with cabozantinib for the treatment of craniopharyngiomas.