bluuebunny/crossref_metadata_2025 huggingface dataset:
TMIC-33. MICROENVIRONMENT-DRIVEN CHANGES IN GLIOBLASTOMA CELL STATE SIGNATURES EXAMINED USING REGION-SPECIFIC HUMAN BRAIN ORGANOIDS
Authors: Bhatia Tarun , Ganta Saisrinidhi , Sing Anson , King Alexia , Sojka Caitlin , Hoang Kimberly , Nduom Edjah , Read Renee , Olson Jeffrey , Sloan Steven
Published: November 2024

Cell state plasticity is retained by all stem-like and differentiated cells within glioblastoma (GBM) tumors. GBM cells can exploit these state-shifting capacities to evade and resist therapeutics. Thus, there is a need to identify and target the regulators of GBM cell state transitions. To address this question, we use a fully human platform where hiSPC-derived organoids serve as a recipient environment to host cells engrafted directly from surgically resected GBMs. This allows us to precisely examine how microenvironmental variables impact the molecular signatures of GBM cells. We acutely isolate GBM cells from surgical resections, label cells with a GFP-lentivirus for 4 hours, and then engraft these tumor cells into parallelly patterned region-specific organoids that mimic dorsal forebrain, ventral forebrain, midbrain, and hindbrain identities. These regions were chosen as they capture derivatives of the three primary brain vesicles and because these regions contain unique cell types and signaling molecules. We performed paired single-cell RNA sequencing on tumor cells pre-engraftment and 14 days post-engraftment. Universal to all regional organoids, we find that GBM cells shift towards a neural progenitor-like and neuron-like signature within organoids, regardless of the cell state of the parent tumor prior to engraftment. To support our findings, we also observed that patient-derived glioma cell lines converge on a neural progenitor-like state within organoids. Thus, the dominance of this shared GBM cell state within organoids implies the existence of shared extrinsic factors in these immature (neurogenic) organoids that favor a progenitor-like or neuron-like identity across all four regions. We are now asking whether this bias towards neuronal and/or neural progenitor identity is a result of engrafting into young neurogenic organoids, or if the same phenomenon could be true in late-stage (post-gliogenic) mature organoids. We are also using this valuable platform and data to identify the extrinsic signals that GBM cells rely on to fulfill their plastic potential, adapt to the microenvironment, and resist therapeutics.
TMIC-52. DECODING METABOLIC INTERACTIONS IN GLIOBLASTOMA TUMOR MICROENVIRONMENT THROUGH COMPREHENSIVE SPATIAL TRANSCRIPTOMIC AND PROTEOMIC ANALYSIS
Authors: Chakraborty Avirup , Yang Changlin , Feier Diana , Silver Aryeh , Anica Miruna , Pittu Avinash , West Illeana , Sobanjo Olusegun , Hodge Ethan , Engelbart Mia , Sengupta Srabasti , Thomas Nagheme , Von Roemeling Christina , Rahman Maryam , Sarkisian Matthew , Huang Jianping , Harrison Jeffrey , Mitchell Duane , Deleyrolle Loic
Published: November 2024

INTRODUCTION

Within the GBM microenvironment, distinct micro-niches arise from independent cancer cell lineages with unique metabolic needs, characterized as Fast Cycling Cells (FCCs) and Slow Cycling Cells (SCCs). FCCs preferentially utilize aerobic glycolysis for energy, whereas treatment-resistant SCCs depend on lipid metabolism. Our study decodes the molecular and spatial heterogeneity within the GBM microenvironment, focusing on the dichotomy of immune infiltrates and the metabolic interactions between SCCs and the immune compartment in human GBM patients.

METHODS

We performed spatial transcriptomics and proteomics combined with geospatially resolved single-cell neighborhood analysis of IHC-stained GBM tissues using CellProfiler and the SNAQ algorithm that we developed to investigate the specific immune microenvironment of SCCs and FCCs. Holotomography and fluorescence-based time-lapse imaging coupled with flow cytometry were used to study lipid transfer between immune cells and GBM cells. Finally, the effects of pharmacological and genetic targeting of lipid transfer were investigated both in vitro and in vivo.

RESULTS

Our study establishes a connection between spatial metabolic heterogeneity and immune diversity, highlighting how specific tumor cell lineages correlate with characteristic immune micro-niches. In particular, SCCs exploit the metabolic properties of recruited immunosuppressive myeloid-derived cells, which metabolically support tumor cells by facilitating lipid transport and supporting SCC metabolism. Our results show that inhibiting lipid transfer affect SCCs, remodels the immune microenvironment, delays tumor growth and improves disease outcome. Our study also demonstrates a correlation between predicted sensitivity to lipid-modifying drugs, such as statins, and the SCC phenotype. This correlation could enable stratification and selection of patients most likely to benefit from such treatments.

CONCLUSIONS

This study establishes critical connections between the TME, cellular metabolism, anti-tumor immunity, and treatment vulnerabilities. Our research provides novel insights into how metabolic exchanges contribute to tumor progression and suggests that targeting metabolic interactions could be an effective therapeutic strategy for GBM.
TMIC-57. EFFECT OF HYPOXIA ON SPHINGOSINE-1-PHOSPHATE (S1P) METABOLIZING ENZYMES IN DIFFUSE INTRINSIC PONTINE GLIOMA CELL LINES
Authors: Russell Hanna , Fillmore Helen
Published: November 2024

Diffuse Midline Glioma H3K27 altered (DMG) is a devastating and incurable paediatric brain tumour. Previously a bioinformatic approach was taken to evaluate genes involved in the sphingosine-1-phosphate (S1P) biosynthesis pathway in diffuse intrinsic pontine gliomas (DIPG). S1P is known to interact with epigenetic partners (HDAC1) as well as play a role in proliferation, immune cell trafficking, angiogenesis and apoptosis. As a part of a broad bioinformatic approach evaluating the expression of genes associated with the sphingomyelin (SM) biosynthesis pathway, S1P metabolism, S1P receptors and downstream targets, 14 of 25 genes were found to be dysregulated in DIPG relative to normal brain (p<0.0002). Herein we focus on the imbalance of the S1P metabolic enzymes sphingosine kinase 2 (SPHK2) and sphingosine-1-phosphate lyase (SGPL1). Bioinformatic data revealed higher levels of SGPL1 and lower levels of SPHK2 compared with normal brain. DIPG cell lines (SU-DIPG-IV, VUMC-DIPG-08, VUMC-DIPG-A) were used to validate gene and protein expression and to evaluate changes following exposure to hypoxic conditions. Confocal images reveal an increase in nuclear SPHK2 staining in cells cultured for 24- and 48-hours under hypoxic conditions. HDAC1 immunostaining was localised in the nucleus. SGPL1 immunostaining, while mostly cytoplasmic, nuclear staining was observed. qRT-PCR assays were used to evaluate changes in mRNA expression in SPHK2, SGPL1 and HDAC1 in DIPG cell lines incubated under hypoxic conditions. The Pfaffl method was used to analyse gene expression relative to the housekeeping gene TBP. Under hypoxic conditions, the levels of SPHK2 and HDAC1 were higher in DIPG cells cultured in hypoxic conditions for 48 hours compared to DIPG cells cultured in normoxic conditions, whereas SGPL1 expression was lower in hypoxic treated cells. Current experiments targeting the modulation of these S1P-metabolizing enzymes are underway to determine the role of the S1P signalling pathway and determine the potential advantage of targeting this pathway in DIPG.
TMIC-68. DEEP LEARNING OF THE SPATIAL IMMUNE ENGAGEMENT IN GLIOBLASTOMA UNDER TEMOZOLOMIDE TREATMENT
Authors: Castillo Simon , Jahedi Afrooz , Gupta Pravesh , Huse Jason , Kannan Kasthuri , Yuan Yinyin , Bhat Krishna
Published: November 2024

Effective immune synapses are a prerequisite for desirable immune surveillance and control of tumour growth. Cell-to-cell interactions form the basis of immune synapses, resulting in either immunoprotected or immunosuppressed manifestations in the tumour brain that could explain glioblastoma (GBM) recurrence. Using state-of-the-art multiplex imaging, spatial statistics, and spatially aware deep learning tools in 14 patient-matching tissues from primary and recurrent GBM, we detected spatial immune networks (SINets). SINets across 105 regions of interest comprising 2.3 million cells show stronger spatial engagement between myeloid and lymphoid lineages at recurrence. SINets’ architecture in primary tumours is associated with relapse timing. Patients, where the SINets are more modular, recur sooner than patients with denser SiNets. In addition, this association presents sexual dimorphism in our cohort (N=3 females, and N=4 males). Phenotype-to-phenotype spatial coexistence also contributes to enhancing phenotype prediction. A spatial-aware deep learning model trained with single-cell data from primary tumours reaches an average balanced accuracy of 0.76 in primary tumour cellular communities unseen during training, compared to a spatial-agnostic model that reached an average balanced accuracy of 0.69. In summary, we detected a distinct spatial engagement in glioblastoma undergoing chemo-radiation treatment. The spatial patterns of coexistence represent ecological niches that contribute to defining cell occurrence and may underpin effective immune synapses. Overall, the spatiotemporal elements provide a newer approach for dissecting glioblastoma’s complexity and discovering opportunities for stratifying patients by harnessing spatial information encoded in multicellular niches.
TMIC-71. ELUCIDATING IMMUNE MICROENVIRONMENTAL DISTINCTIONS BETWEEN IDH-MUTANT ASTROCYTOMA AND OLIGODENDROGLIOMA USING SINGLE-CELL TRANSCRIPTIONAL PROFILING
Authors: Whitfield Benjamin , Liu Yang , Gupta Pravesh , Oberai Shivangi , Bhat Krishna , Huse Jason
Published: November 2024

Despite exhibiting longer overall survival that IDH-wt counterparts, IDH-mutant gliomas remain uniformly deadly and impact patients in the prime of adult life. The immune microenvironment of IDH-mutant gliomas remains incompletely characterized, particularly with regard to distinctions between IDH-mutant astrocytoma and IDH-mutant, 1p/19q codeleted oligodendroglioma. To address this knowledge gap, we subjected dissociated tumor suspensions derived from 7 astrocytoma and 7 oligodendroglioma clinical samples to flow cytometry-based sorting for the pan-immune marker, CD45, and the microglial marker, P2RY12. This process yielded both microglial and non-microglial immune cell populations, which were then analyzed by scRNA sequencing. This workflow revealed a single large cluster of microglia, characterized by expression of Galectin-1 and lysosomal Lipase A, which was present at a significantly higher level in oligodendroglioma. While the biological significance of this cluster is unclear, gene set enrichment analysis exploring phenotypic differences between microglia in astrocytoma and oligodendroglioma revealed significant increases in expression of gene sets related to antigen presentation in astrocytoma. Parallel analysis of the non-microglial immune fraction showed an increase in the expression of pro-inflammatory gene sets, such as genes related to cytokine secretion, within the CD8 T-cell compartment of astrocytomas. We also observed upregulation of the expression of inflammatory gene sets within the dendritic cells of astrocytomas. Taken together, these changes suggest that the immune compartment of astrocytoma is more active and inflamed, and targeting the immune system in these tumors may represent a potential therapeutic avenue.
TMOD-05. GLIOMA-ASSOCIATED OLIGODENDROCYTE PROGENITOR CELLS’ DYNAMIC PATTERNS SUGGEST FUNCTIONAL ADAPTATIONS DURING GLIOMA PROGRESSION IN A UNIQUE MOUSE MODEL
Authors: K Petritsch Claudia , Xing Lulu , Bui Brandon
Published: November 2024

Gliomas account for more than one-third of brain tumors in children, with high fatality rate despite aggressive adjuvant treatment. Two-thirds of survivors suffer from health conditions due to the toxicity of conventional therapies. Notably, gliomas with the BRAFV600E mutation, occurring in ~20% of all glioma cases, are difficult to treat and have a high risk for progression, especially when combined with CDKN2A deletion. The mechanisms for glioma progression remain unclear and unraveling them could lead to therapies that inhibit glioma progression, preventing high-grade gliomas. Objectives: To gain mechanistic insights into glioma progression and exploit therapeutically for preventing progression. We developed two novel mouse models for BRAFV600E mutant progressive gliomas – one at high genetic risk for progression and one at intermediate genetic risk for progression. Expression of genetic alterations were induced by injecting compound transgenic mice with adenovirus-Cre. Our new mouse models therefore more faithfully recapitulated the genetic changes accompanying glioma formation and progression from low- to high-grade than earlier mouse models which used the RCAS system to overexpress the oncogene (PMCID: PMC11112369 ). Glioma formation was followed non-invasively by magnetic resonance imaging. Single cell RNA sequencing and spatial transcriptomics were performed and immunofluorescence was used for validation (PMCID: PMC10619673 ). We present new data showing that animal subject survival is significantly shorter in the high risk model than in the low risk model. Our two models with distinct latency can be used for preclinical studies and studies of the changes associated with progression, including in the glioma microenvironment. Analyses revealed temporal, functional, and spatial changes in glioma-associated oligodendrocyte progenitor cells (GA-OPCs) at distinct stages (initiation, expansion, progression) and grades. Our findings that GA-OPCs closely interact with glioma cells and their morphological transformation as gliomas progress, suggest changing functions, including potential roles in phagocytosis and immunomodulation. Understanding the unclear role of glioma microenvironment OPCs in promoting glioma progression could reveal an Achilles heel for targeted therapies.
TMOD-09. NEWLY DESIGNED TUMOR TREATING FIELDS (TTFIELDS) ARRAYS FOR THE MOUSE HEAD DEMONSTRATE EFFICACY FOR TREATMENT OF GLIOBLASTOMA
Authors: Zbidat Sewar , Blatt Roni , Sellevoll Mariell , Gabay Martin , Schlachet Inbar , Cahal Shay , Davidi Shiri , Tzchori Itai , Haber Adi , Giladi Moshe , Palti Yoram
Published: November 2024

Tumor Treating Fields (TTFields) therapy is a cancer treatment modality based on continuous, non-invasive delivery of electric fields. TTFields therapy is approved for treatment of glioblastoma (GBM), delivered to the patient’s brain by two array pairs placed on the scalp. Further research in animals to expand the knowledge regarding TTFields treatment of GBM is limited, as this is mainly performed in mouse models and arrays for application of TTFields to the mouse head are lacking. The small dimensions and specific geometries of the mouse head make the development of such arrays challenging. The aim of this study was to design arrays that will allow efficient and stable delivery of TTFields to the mouse head. To overcome the small head size, we developed a layout with two arrays situated on the head of the mouse, each divided into two smaller disks, and positioned opposite two arrays on the torso. We identified a thin and transparent adhesive tape (facilitating correct array positioning) with good tackiness and easy removal (without leaving residual adhesive on the skin). The arrays met the minimum treatment requirements: current ≥ 50 mA, usage ≥ 75%, field intensity ≥ 1 V/cm RMS. We then conducted an efficacy study with the new arrays, using GL-261 GBM cells intracranially injected into C57BL/6 mice. Treatment with sham-heat (control) or TTFields was initiated 11 days following tumor inoculation and maintained continuously for 12 days. Efficacy was measured via magnetic resonance imaging (MRI) of tumor volume, showing a decrease of 31% at treatment end in TTFields-treated mice versus the control. Overall, the new arrays are flexible, strongly adherent, deliver TTFields at a sufficient intensity, and showed efficacy for treating GBM in mice.
TMOD-14. ESTABLISHING A CLINICALLY RELEVANT MOUSE MODEL TO STUDY NECROSIS AS A PRIMARY VARIABLE IN GLIOBLASTOMA
Authors: Li Jiabo , Shih Ling-kai , Markwell Steven , Olson Cheryl , Sullivan David , Lam Nicholas , Brat Daniel
Published: November 2024

All glioblastoma (GBM) molecular subsets share the common trait of accelerated progression following necrosis, which cannot be adequately explained by cellular proliferation arising from accumulated genetic alterations. We suggest that necrosis is much more than a passive phenomenon related to rapid growth but rather is a driving force causing tumor microenvironment (TME) restructuring and biologic progression. yet mechanisms remain poorly understood due to a lack of animal models to study necrosis as a primary variable. In GBM, the most malignant primary brain tumor, vascular pathology and central necrosis precede rapid, radial expansion. To reveal spatio-temporal changes directly following vascular damage in the brain, we developed methodology to induce clinically relevant thrombosis vaso-occlusion within GBMs in immunocompetent RCAS/tv-a mouse model to study TME restructuring by intravital microscopy and demonstrate its impact on glioma progression in real-time. We found that following Rose Bengal photothrombosis, GBMs rapidly expanded radially, with glioma migration away from central necrosis and tumor-associated macrophages (TAMs) and glioma stem cells (GSCs) increased dramatically in the peri-necrotic zones. Through the single cell tracking analysis, we found that TAMs displaying increased displacement toward necrosis and greater overall migration distances. Collectively, this model introduces necrosis as the primary variable and captures glioma growth dynamics and TME restructuring in a manner that will facilitate the development of therapies that antagonize these mechanisms to improve outcomes.
TMOD-16. ZUCLOPENTHIXOL REDUCES ACTIVITY-DEPENDENT GLIOBLASTOMA PROLIFERATION
Authors: Negussie Mikias , Krishna Saritha , Daniel Andy , Gonzales Cesar Nava , Hervey-Jumper Shawn
Published: November 2024

A major challenge in modeling glioblastoma in the laboratory is the complex microenvironment in which tumors evolve in humans. The varied architecture and immune privilege of the brain limits the external validity of many experiments performed in modern cell biology laboratories. Organotypic human cortical slices present an opportunity to model glioblastoma and test the effect of drugs against glioma in ex-vivo human tissue. Cortical slice cultures maintain the cellular organization of the human brain, more closely approximating glioblastoma proliferation in patients. In this study, we test the effect zuclopenthixol, a repurposed antipsychotic inhibitor of glioblastoma-induced neuronal hyperexcitability, on the proliferation of glioblastoma cells in an organotypic human cortical slice culture. Primary patient-derived glioblastoma cultures were established, and human cortical tissues were emersed in oxygenated ACSF agarose gel before preparing 250 µm thick slices. Slices were either exogenously seeded with glioblastoma cells or stained for endogenous tumor infiltration. Slices with either endogenous or exogenous seeding were then treated with zuclopenthixol or regular media change and cultured for 10 days. Proliferation was measured with Ki67 staining and quantified via automated pixel summation using the Pillow library in Python. 0.1 µM zuclopenthixol treated slices had significantly lower proliferation index in both the endogenous tumor condition (0.04 vs 0.30, P < 0.05) and the exogenous seeding condition (0.0013 vs 0.028, P = 0.033). Reduced tissue integrity was observed beginning day 8 of culture, as tissue surrounding tumor seeding sites eroded. Here, we model glioblastoma proliferation in live human tissue and quantify the anti-proliferative effect of zuclopenthixol. We show that zuclopenthixol treatment significantly reduced the proliferation index. Our experimental model allowed the optimization of organotypic human cortical slice cultures for immunofluorescence studies and live-cell imaging.
TMOD-17. FOXR2-ACTIVATED CNS NEUROBLASTOMA ORIGINATES FROM THE MEDIAL GANGLIONIC EMINENCE LINEAGE
Authors: Royston Hitomi , Hampton Autumn , Bhagat Dhruv , Pinto Evonne , Emerson Miriam , Funato Kosuke
Published: November 2024

FOXR2-activated CNS neuroblastoma is a rare subtype of pediatric brain tumor characterized by the elevated expression of the transcription factor FOXR2 due to genomic rearrangement. However, the precise pathogenic mechanisms, including the cell type of origin and the function of FOXR2, are not fully understood. An expression profile analysis of patient tumors showed increased expression of the marker genes associated with the Medial Ganglionic Eminence (MGE) in the ventral forebrain such as NKX2.1 and SOX6. Based on this result, we hypothesized that FOXR2-activated CNS neuroblastoma originates from the MGE lineage. To test this hypothesis, we overexpressed FOXR2 in human embryonic stem cell-derived MGE progenitors and, as a control cell type, cortical progenitors. Our data showed that FOXR2 overexpression resulted in a significantly increased proliferation in the MGE progenitors but not in the cortical progenitors, indicating a cell-type-specific effect of FOXR2. When injected into the brain of immunodeficient mice, FOXR2-expressing MGE progenitors formed tumors that molecularly resemble patient tumors, while FOXR2-expressing cortical progenitors did not. To further dissect the underlying molecular mechanisms, we conducted an RNA-seq experiment and found that FOXR2 overexpression activated the MEK/ERK signaling pathway through a suppression of the endogenous RAS inhibitor DIRAS3. Moreover, the FDA-approved MEK inhibitor trametinib significantly suppressed the proliferation and induced cell death in FOXR2-expressing MGE progenitors in vitro with the IC50 value of 30 nM. Collectively, our study has revealed the cell type of origin of FOXR2-activated CNS neuroblastoma and identified the MEK/ERK pathway as a critical downstream of FOXR2 that can be targeted therapeutically.
TMOD-18. FUNCTIONAL DISSECTION OF RECURRENT COPY-NUMBER-ALTERATIONS INFORMS MECHANISMS OF LOW-GRADE-GLIOMA PROGRESSION
Authors: Haider Shahan , Drucker Kristen , Kollmeyer Thomas , Tsai Ricky , Al-Zahrani Khalid , Chiu Cynthia H , Elia Andrew , Jenkins Robert , Schramek Daniel
Published: November 2024

Low-grade gliomas (LGG) are slowly growing brain cancers that ultimately undergo a malignant progression to lethal secondary glioblastomas with a dismal prognosis. Despite intensive research, very little progress has been made in our understanding of this transformation. Hence, outside of known alternations in well-characterized driver genes CDKN2A, PTEN and PDGFRA, genetic drivers that underlie LGG transformation are largely unknown. Contrary to other types of cancer, LGGs exhibit very few driver mutations (30-40 mutations) as they progress. Interestingly, LGGs also exhibit a highly prevalent and heterogenous pattern of copy-number-alterations (CNAs) suggesting that they might be driven by changes in gene dosages that result from widespread chromosomal instability observed within these tumors. Through analysis of the human Mayo Clinic and TCGA LGG datasets (~1500 patients), we have identified eleven highly recurrent CNAs affecting LGG patients, many of which correlate with patient survival. We hypothesized that these CNAs contain driver genes that confer a growth advantage resulting in the highly recurrent CNA pattern and prognostic associations. To investigate the tumor suppressive potential of the ~1800 genes located in recurrently deleted regions and the oncogenic potential of the ~1200 genes located in recurrently amplified regions, our lab developed a novel in vivo ‘CRISPR-Knock Out and Activation Linked Assay’ (CRISPR-KOALA). Stereotaxic delivery of arm-level CNA lentiviral gRNA libraries targeting the mouse orthologs of genes in CNAs into the brain of our animal model (rs557mut;IDHmut;P53KO;AtrxKO;Cas9GFP: Yanchus et. al Science 2022) resulted in rapid formation of tumors compared to animals injected with control libraries. Deconvoluting the screen revealed enrichment of immune modulators such as Them6 as well as a modulator of NMDA receptors (Grina) implicating immune system and glutamate dysregulation in LGG malignant transformation. Taken together, our study provides insights into mechanisms underlying LGG progression which may serve to inform intervention strategies for this lethal disease.
TMOD-27. RECURRENT GLIOBLASTOMA AFTER LASER ABLATION OF THE PRIMARY TUMOR IN A PRECLINICAL ORTHOTOPIC MODEL EXHIBIT INCREASED GENETIC SIGNATURES OF CELL CYCLE AND CELL MOTILITY
Authors: Nagaraja Tavarekere , Lee Ian
Published: November 2024

Image-guided laser interstitial thermal therapy (LITT) is a minimally invasive tumor cytoreductive treatment for recurrent gliomas and tumors in eloquent loci. We have adapted this technique to develop an image-guided glioblastoma (GBM) ablation model, its recurrence and have tested the efficacy of imaging biomarkers in evaluating tumor ablation and recurrence. The cytopathology and molecular signatures of the primary and recurrent tumors were compared. Immune-compromised female rats were implanted with U251N tumor cells in one brain hemisphere (n=20). Tumor growth was monitored using magnetic resonance imaging (MRI). When tumors reached about 4 mm in diameter, they were ablated using a clinical LITT system (Visualase®), under MRI guidance. Five other rats implanted with U251N tumors were used as unablated controls. MRI data were acquired at 24 h post-LITT, and at 2 and 4 weeks. Rats were sacrificed for histopathology at 2 and 4 weeks, and brain sections stained for hematoxylin and eosin, human major histocompatibility complex, Ki67, a cell proliferation marker and sex determining region Y)-box 2 (SOX2), a stem cell transcription factor. An additional cohort of rats with primary (n=4) and post-LITT recurrent (n=4) U251N tumors were used for analysis of their molecular composition using RNA-Seq approach. In the treated groups, MRI showed little tumor tissue at 24 h, evidence of recurrence at 2 weeks and significant tumor tissue at 4 weeks. Tumor DCE-MRI parameters showed elevated intra-tumoral vascular permeability (i.e., Ktrans) values at pre-LITT imaging, that shifted to peri-ablation periphery at 24 h. A trend of progressive decrease in Ktrans was seen until 1-week post-ablation. Increasing Ktrans values at 2 weeks and after 4 weeks coincided with tumor recurrence. RNA-Seq data showed that cell cycle, cellular movement and inflammatory disease genes were the most differentially expressed genes in the recurrent tumors suggesting increased infiltration may primarily underlie treatment resistance.
TMOD-31. SINGLE-CELL PROFILING AND CHARACTERIZATION OF PATIENT-DERIVED XENOGRAFT GLIOBLASTOMA MODEL IN HUMANIZED MICE
Authors: Takei Jun , Furudate Ken , Iwaloye Opeyemi , Nagaoka-Kamata Yoshiko , Blucas Madison T , Azolibe Stella U , Jepson Chloe E , Saito Kiyotaka , Miller C Ryan , Van Meir Erwin G , Kamata Masakazu , Osuka Satoru
Published: November 2024

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor in adults, and the current standard therapy has limited efficacy. To develop effective therapies, it is desirable to develop an animal model that can replicate the tumor heterogeneity and immune microenvironment of human GBM. Here, we describe a novel GBM mouse model established with a patient-derived xenograft (PDX) in humanized mice harboring a nearly complete human immune environment. Humanized mice were generated by engrafting human CD34+ hematopoietic stem cells from umbilical cord blood into immunocompromised mice (NSG, NSG-SGM3, and NOG-EXL) after myeloablation. NSG-SGM3 is a triple transgenic mouse encoding human IL3, GM-CSF, and SCF on the NSG strain background. NOG-EXL is a NOG strain with human IL3 and GM-CSF expression. These cytokines foster the development of the human myeloid lineage and its differentiation. NSG-SGM3 and NOG-EXL were superior in immune cell reproducibility, especially myeloid cells. Radioresistant PDX GBM cells established after repeated irradiation were injected into the forebrain of humanized mice and the same immunocompromised mice without humanization. Human PDX GBM cells formed aggressive tumors with similar growth speed in the humanized mice compared to non-humanized mice; however, their dissemination to the spinal cord was significantly suppressed in humanized mice, suggesting that human immune cells impact the spinal dissemination of GBM cells. Single-cell RNA sequencing analysis revealed infiltration of human CD4+ T, CD8+ T, NK cells, and macrophages, as well as infiltration of regulatory T and exhausted CD8+ cells into the brain tumor, reflecting the immunosuppressive landscape of recurrent human GBM. Furthermore, we found that tumor heterogeneity was increased in humanized mice compared to non-humanized mice. There was a notable rise in neural progenitor-like cell populations, indicating tumor adaptation to immune pressures. This novel GBM-PDX humanized mouse model might be highly beneficial for analyzing the interaction between human tumor cells and human immune cells, and evaluating the effect of immunotherapies.
TMOD-35. EGFRVIII OVEREXPRESSION AND LOSS OF MOUSE SPECIFIC CDKN2A IN GLIAL CELLS LEADS TO SPONTANEOUS GLIOMAGENESIS IN A NOVEL MOUSE MODEL
Authors: Singh Olivia , Voisin Mathew , Li Mira , Ali Hafsah , Wei Qingxia , Gao Andrew , Agnihotri Sameer , Burrell Kelly , Wilson Mark , Kamiri Shirin , Bunda Severa , Aldape Kenneth , Zadeh Gelareh
Published: November 2024

A new mouse model for the classical subtype of human glioblastoma (GBM) has been bred using Cre-mediated EGFRvIII overexpression and homozygous p19-ARF deletion, the mouse homolog of human p14ARF/CDKN2A, in GFAP expressing cells. Transgenic mice develop intraparenchymal and/or leptomeningeal brain lesions with some spinal cord invasion as early as 1 month old and 95% of mice die by 6 months due to hydrocephalus and/or paralysis. Mice with high grade tumors have worse survival and similar features to human classical GBM such as necrosis, high levels of mitosis and infiltration of tumor cells into normal brain. Immunohistochemical analysis confirms EGFRvIII overexpression and p19-ARF loss in Cre-expressing cells, along with patchy positive GFAP and high proliferation by Ki67. Bulk RNA sequencing reveals GEC3 tumors cluster closely with human classical GBM and have significant upregulation of downstream markers in the JAK/STAT and P13K/AKT pathways. Adherent and neurosphere primary culture of dissociated tumors indicate that tumor cells maintain EGFRvIII expression in culture and generate xenograft tumors by 3 weeks after intracranial injections into NODSCID mice. Xenograft tumors are reminiscent of the primary tumor, with similar histopathological features and immunohistochemical staining. Our spontaneous glioma model is a powerful tool for future studies focused on the role of the immune microenvironment on glioma recurrence and resistance.
Robustly Optimal Mechanisms for Selling Multiple Goods
Authors: Che Yeon-Koo , Zhong Weijie
Published: November 2024

We study robustly optimal mechanisms for selling multiple items. The seller maximizes revenue against a worst-case distribution of a buyer’s valuations within a set of distributions, called an “ambiguity” set. We identify the exact forms of robustly optimal selling mechanisms and the worst-case distributions when the ambiguity set satisfies various moment conditions on the values of subsets of goods. The analysis reveals general properties of the ambiguity set that justifies categorical bundling, which includes separate sales and pure bundling as special cases.
Prevalence and Prognosis of Coronal Malalignment Following Lateral Lumbar Interbody Fusion for Minimally Invasive Treatment of Adult Spinal Deformity
Authors: Chan Andrew K. , Sampath Shailen G. , Mummaneni Praveen V. , Park Paul , Uribe Juan S. , Turner Jay D. , Le Vivian P. , Eastlack Robert K. , Fessler Richard G. , Than Khoi D. , Fu Kai-Ming , Wang Michael Y. , Kanter Adam S. , Okonkwo David O. , Nunley Pierce D. , Anand Neel , Mundis Gregory M. , Passias Peter G. , Bess Shay , Shaffrey Christopher I. , Chou Dean ,   the International Spine Study Group
Published: November 2024

Study Design:

Retrospective analysis of prospective multicenter adult spinal deformity (ASD) database.

Objective:

To determine the prevalence and prognosis of postoperative coronal malalignment following LLIF for ASD with Qiu type A coronal alignment.

Summary of background data:

Qiu Type A coronal alignment is defined as coronal vertical axis (CVA) <30mm.1 There is concern that circumferential minimally invasive surgery (cMIS) with lateral lumbar interbody fusion (LLIF) is associated with postoperative coronal malalignment in ASD with preoperative Qiu type A patients.

Methods:

Qui type A patients undergoing cMIS with LLIF for ASD were included, with ASD defined with at least: maximum CC≥20°, SVA>5 cm, PI-LL≥10°, or PT>20°. Two year (2Y) clinical outcomes were compared for type A with 2Y CVA≥30 mm (MAL) versus <30 mm (ALIGN) and were adjusted for factors reaching P<0.05 on univariate comparisons (age, BMI, and ODI).

Results:

43 patients met inclusion criteria, of which 12 (27.9%) developed coronal malalignment and 31 (72.1%) remained coronally aligned at 2Y. At baseline, MAL were older (73.0 vs. 69.0, P=0.045), had a lower BMI (26.09 vs. 29.45, P=0.047), and were less disabled (ODI 42.83 vs. 51.69, P=0.016). Otherwise, the groups were well-matched for baseline characteristics. At 2Y, MAL had a greater 2Y SVA (mean 54.08 vs 19.00 mm, P=0.01). Clinically, MAL was associated with inferior 2Y SF-36 PCS (34.78 vs. 37.42, adj P=0.043) and 2Y SRS-22r function/activity domain (3.03 vs. 3.36, adj P=0.040), but otherwise similar in other patient-reported-outcome-metrics (adj P>0.05 for all). 2Y complications were similar between groups, including for reoperations and major and minor complications (adj P>0.05 for all).

Conclusions:

In Qui type A patients undergoing cMIS with LLIF for ASD, 27.9% develop coronal malalignment, which was associated with worse SF-36 PCS and SRS-22r function/activity. Despite radiographic malalignment, malalignment was not associated with higher 2-year complication rates including reoperations.
The Need for Institutional Policies for Innovative Therapy: Existing Approaches and Key Elements
Authors: Rao Emily , Grady Christine , Wendler David
Published: November 2024

OBJECTIVES:

Innovative therapy is common in many areas of medicine. Yet, it is unknown whether medical centers have policies to ensure innovative therapy is conducted appropriately.

DESIGN:

We contacted three informants at leading U.S. medical centers to determine whether the center has a policy for innovative therapy and, if so, what requirements the policies include and whether the policies lack any important elements.

SETTING:

Existing policies and published recommendations.

PATIENTS:

None.

INTERVENTIONS:

None.

MEASUREMENTS AND MAIN RESULTS:

Our search found that 46 of 58 responding centers (79%) do not have a policy for innovative therapy. Of the ten policies available for review, half lack requirements to report patient outcomes, and half do not explicitly coordinate innovative therapy with research.

CONCLUSIONS:

A majority of leading U.S. medical centers do not have a policy for innovative therapy. In addition, existing policies lack important elements, especially with respect to reporting patient outcomes and coordinating innovative therapy with research. Based on the existing policies and recommendations in the literature, we thus identify eight key elements that should be included in policies for innovative therapy. Future research should assess whether these elements can be feasibly implemented and whether, in practice, they offer patients appropriate protection.
The Clinical Characteristics and Virus Shedding of Omicron Patients in a Shanghai Mobile Cabin Hospital
Authors: Wen Yuchan , Xie Qinli , Liu Xinquan , Kong Qinghao , Zhang Yan , Liu Min , Huang Jing
Published: November 2024

Background

Information about characteristics of Omicron-infected patients and estimation of risk factors for the duration of viral shedding were unclear.

Methods

This retrospective study included asymptomatic patients and patients with mild symptoms, who were infected with Omicron and hospitalized in a Shanghai mobile cabin hospital. The clinical characteristics of those patients were summarized, and the influencing factors of severe acute respiratory syndrome coronavirus 2 virus shedding were explored.

Results

Multivariate logistic regression analysis indicated that comorbidities (odds ratio [OR], 1.991; 95% confidence interval [CI], 1.365–2.904; P = 0.000), 2 doses of vaccines (OR, 2.421; 95% CI, 1.636–3.584; P = 0.000), 3 doses of vaccine/booster shots (OR, 3.797; 95% CI, 2.607–5.529; P = 0.000), and virus shedding time (OR, 1.078; 95% CI, 1.053–1.103; P = 0.000) were associated with increased odds of mild symptoms in Omicron patients, whereas age (OR, 0.951; 95% CI, 0.940–0.963; P = 0.000) was associated with a reduced risk of mild symptoms. The median length of virus ribonucleic acid shedding time was 10 days. Being male (OR, 1.868; 95% CI, 1.488–2.345; P < 0.001), age (OR, 1.018; 95% CI, 1.008–1.028; P < 0.001), and a diagnosis of mild symptoms (OR, 1.508; 95% CI, 1.244–1.895; P < 0.001) were risk factors of prolonged shedding time in multivariate regression analysis. The cycle threshold values of nucleocapsid protein and open reading frame 1ab genes in Omicron patients with virus shedding time ≤10 days are significantly different from that in patients with virus shedding time >20 days (P < 0.001).

Conclusions

Being male, being older, and having a mild case were all risk factors for prolonged virus shedding time, and patients with high viral load may have long virus shedding time. Patients who are young, have complications, and have been vaccinated with 2 or 3 doses/enhanced vaccines with long virus shedding time increased the risk of clinical symptoms.
Intraocular lens rotational stability after cataract surgery with and without primary posterior continuous curvilinear capsulorhexis
Authors: Huang Yulong , Yu Mengting , Liu Xiaobao , Cai Yajing , Kang Chishan , Wu Wenjie
Published: November 2024

Purpose:

To evaluate intraocular lens (IOL) rotational stability and capsular fusion process after cataract surgery with and without primary posterior continuous curvilinear capsulorhexis (PPCCC).

Setting:

Fujian Provincial Hospital, Fujian, China.

Design:

Prospective, intraindividual, randomized clinical trial.

Methods:

This study included 56 adult patients (112 eyes) with bilateral cataract undergoing phacoemulsification cataract surgery with PPCCC in 1 eye (PPCCC group) and conventional cataract surgery in the contralateral eye (NPCCC group). IOL axis orientation and fusion footprint length were measured at 1 day, 1 week, 1 month, 3 months, and 1 year postoperatively using OPD-Scan III, while the capsular bend index (CBI) was assessed at the same timepoints using Pentacam AXL.

Results:

No between-group difference was found in the absolute rotation from 1 day to 1 year (2.93 ± 1.72 vs 2.66 ± 1.61 degrees, P = .54). The absolute rotation from 1 week to 1 month in the NPCCC group was higher than that in the PPCCC group (1.65 ± 0.68 vs 1.27 ± 0.32 degrees, P = .01). At 1 month postoperatively, both fusion footprint length (9.11 ± 2.74 vs 10.67 ± 2.06 mm, P = .02) and CBI (2.92 ± 0.60 vs 3.25 ± 0.59, P = .03) were lower in the NPCCC group.

Conclusions:

Cataract surgery involving PPCCC demonstrated comparable outcomes with conventional procedures regarding long-term IOL rotational stability and therefore is a promising option for adult patients with cataract scheduled for toric IOL implantation. PPCCC slightly reduces IOL rotation in the early postoperative period, which can be attributed to accelerated capsular fusion.
Social Demographic and Clinical Predictors of Time to Clinic Presentation After a Sport-Related Concussion
Authors: Amedy Amad , Williams Kristen , Prosak Olivia L. , Anesi Trevor , Zuckerman Scott L. , Terry Douglas P.
Published: November 2024

Objective:

To investigate the associations between clinical risk factors, social demographic and time to concussion clinic presentation after sports-related concussion in young athletes.

Design:

Retrospective cohort study.

Setting:

Multidisciplinary regional concussion center.

Patients:

Athletes ages 12 to 18 years who sustained a SRC from November 2017 to April 2022.

Independent Variables:

Independent variables included social demographic factors (ie, race, ethnicity, public vs private school, public vs private insurance), patient medical history, family medical history, acute concussion characteristics, and initial presentation elsewhere.

Main Outcome Measures:

Descriptive statistics were employed to assess for group differences. Mann–Whitney U tests, Spearman rank order correlations, and linear regressions were performed to explore associations between each independent variable and the main outcome, days to concussion clinic presentation.

Results:

A total of 945 athletes we included (age 15.8 ± 1.61, 33.7% female). Hispanic/Latino background, (P = 0.009), public insurance status (U = 47 377.0, P = 0.002), amnesia (U = 57 738.0, P = 0.002) at time of injury, family psychiatric (U = 35 091.0, P < 0.001) or migraine (U = 59 594.5, P < 0.001) histories, and personal psychiatric (U = 30 798.0, P = 0.004) or migraine (U = 34 133.5, P = 0.011) histories were associated with longer time to concussion clinic presentation. A multivariable linear regression found that initial presentation elsewhere (β = 0.37, P < 0.001), family migraine history (β = 0.18, P < 0.001), public insurance status (β = 0.09, P = 0.024), and history of learning disability (β = 0.09, P = 0.032) were the only predictors of longer time to concussion clinic presentation.

Conclusions:

Variables that predicted longer time to concussion clinic presentation included initial presentation elsewhere, public insurance status, positive family migraine history, and history of learning disability. Further research is needed to elucidate these findings and determine how they impact concussion seeking behavior.
The Effect of the Nordic Hamstring Exercise on Hamstring Muscle Activity Distribution During High-Speed Running Estimated Using Multichannel Electromyography: A Pragmatic Randomized Controlled Trial
Authors: Suskens Jozef J. M. , Maas Huub , van Dieën Jaap H. , Kerkhoffs Gino M. M. J. , Tol Johannes L. , Reurink Gustaaf
Published: November 2024

Objective:

To evaluate the effect of the Nordic hamstring exercise on normalized muscle activity and relative contribution of the biceps femoris long head, semitendinosus, and semimembranosus through multichannel electromyography in the late-swing phase of high-speed running.

Design:

A pragmatic, 2-arm, single-center randomized controlled trial. Participants were randomly assigned to a Nordic group or control group.

Setting:

Dutch male basketball.

Participants:

Twenty injury-free players (mean age 18 ± 3 years).

Intervention:

A 12-week Nordic hamstring exercise intervention.

Main Outcome Measures:

Level of normalized muscle activity (percentage maximal voluntary isometric contraction [%MVIC]) and relative contribution (%con) of hamstring muscles for 12 weeks.

Results:

The Nordic hamstring exercise intervention did not result in significant changes for 12 weeks. For normalized muscle activity, between-group differences (compared with the control group) for 12 weeks were 11.4 %MVIC (95% confidence interval [95% CI]: −11.0, 33.8) for the biceps femoris long head, −9.4 %MVIC (95% CI: −23.3, 5.2) for the semitendinosus, and −2.7 %MVIC (95% CI: −15.8, 10.3) for the semimembranosus, P = 0.151. For relative contribution, between-group differences for 12 weeks were −6.1 %con (95% CI: −2.4, 14.6) for the biceps femoris long head, −7.0 %con (95% CI: −13.6, −0.4) for the semitendinosus, and 0.9 %con (95% CI: −9.2, 11.0) for the semimembranosus P = 0.187. Positive values are in favor of the Nordic group.

Conclusions:

A 12-week Nordic hamstring exercise intervention did not affect the level of muscle activity and relative contribution of hamstring muscles in the late-swing phase of high-speed running. Because of the low amount of data sets, results should be interpreted cautiously.
Visual analysis of patient safety research hotspots and trends in the context of telemedicine based on Web of Science
Authors: Wen Caijin , Luo Wenxia , Liu Yan , Luo Xi , Li Jie , Zhang Jing
Published: November 2024

To analyze the research status, hotspots, and trends of patient safety in the context of international telemedicine, and to provide reference for future research in various countries. The literature pertaining to patient safety within the realm of telemedicine was systematically retrieved from the Web of Science core collection database, encompassing the period from January 2010 to December 2023. Visual analysis of publication quantity, primary authorship, and keyword trends was conducted using CiteSpace (6.2R6) software. The geographical distribution of research focus was visualized through VOSviewer software and SCImago Graphica software, while research institutions were depicted using VOSviewer software and Highcharts software. Data organization was facilitated by Excel 2019 software. A total of 5356 related articles were included, and the number of published papers showed an overall upward trend, and the countries and institutions with the largest number of papers were the United States and Harvard University, respectively, and a stable core author research population had not yet been formed in this research field. Through keyword analysis, it can be seen that the research hotspots mainly focus on the research on the influencing factors of patient safety in the context of telemedicine, the research on the application value of telemedicine, and the research on coping strategies that affect patient safety. The research on patient safety in the context of telemedicine in foreign countries has a certain depth and breadth, which has important reference significance for improving the medical quality and patient safety of Internet hospitals in various countries.