bluuebunny/crossref_metadata_2025_split huggingface dataset:
TMIC-01. TARGETABLE GENE EXPRESSION CHANGES MEDIATE EXTRAVASATION OF BREAST CANCER CELLS FROM THE CIRCULATION AND LOCAL PROLIFERATION IN THE BRAIN
Authors: Kalistratova Venina , Morshed Ramin , Chalif Eric , Gill Sabraj , Khela Harmon , Lad Meeki , Sati Ankita , Mathur Aakriti , Aghi Manish 
Published: November 2024

Abstract
As breast cancer migrates into the brain, it acquires distinct genomic, immunologic and phenotypic changes through interactions with the local microenvironment. We sought to determine how targetable gene expression changes mediate breast cancer extravasation into and proliferation within the brain. We created a brain metastatic cell line (“brain-seeking”) via serial intracardiac injection of mCherry+ 4T1 breast cancer cells in Balb/c mice and flow cytometry isolation of micrometastases. We conducted in vitro and in-vivo studies to uncover immunological and genetic differences between primary breast cancer and brain metastases. In culture, we observed significant upregulation in adhesion (p=0.01) and invasion (p=0.0004) along with upregulation of adhesion-promoting genes such as Sdc3, Serpine2 or ECM1 in brain-seeking cells. We observed significant differences in survival of Balb/c mice injected intracranially with brain-seeking cells vs. breast cancer cells (p=0.04). In the mammary fat pad (MFP), parental 4T1 cells caused increased mortality vs. brain-seeking cells (p=0.003). This rejection of brain-seeking 4T1 cells in the MFP could be due to prior adaptation to the brain microenvironment, while rejection of parental 4T1 cells in the brain could be due to lacking said adaptations. Consistent with this finding, of 20,382 analyzed genes in both cell lines, 108 related to immune regulation were significantly upregulated in brain-seeking cells including Cxcl1, Dusp1, C3. Flow cytometry showed increased cytotoxic and helper T cells in intracranially injected parental vs. brain-seeking cells (p &lt;0.001). In the MFP, however, 4T1 parental cells displayed CD3+ T cell depletion and an increased number of neutrophils (p &lt;0.05) while the “brain-seeking cells” showed increased numbers of CD3+ and CD4+ cells (p &lt;0.01) and macrophages (p&lt;0.05). This suggests that brain metastases evolve from their primary tumor through adhesive and invasive adaptations promoting extravasation, along with unique immunological adaptations that allow their proliferation free of immune surveillance in the brain microenvironment.
TMIC-02. SINGLE-CELL HIGH-DIMENSIONAL MASS CYTOMETRY (CYTOF) REVEALS IMMUNE LANDSCAPE OF PITUITARY NEUROENDOCRINE TUMORS
Authors: Guo Xiaopeng , Chang Mengqi , Huang Yongsheng , Zhang Fan , Zhao Yuanli , Xing Bing 
Published: November 2024

Abstract
Pituitary neuroendocrine tumors (pitNETs) are a group of neoplasms in the sellar region, ranking as the second most common primary brain tumors, with some exhibiting aggressive behaviors. While immunohistochemical staining has been utilized to characterize the tumor immune microenvironment (TIME) of pitNETs, single-cell analysis remains underexplored. High-dimensional mass cytometry (CyTOF) offers a valuable approach for precise quantification of intratumoral leukocytes and potential therapeutic insights. We prospectively enrolled 56 patients with pitNETs of varying endocrine function, histology, and lineage. CyTOF, employing heavy metal-tagged antibodies, was employed to simultaneously measure 37 cellular parameters at single-cell resolution. Analysis revealed a total of 71,049 CD45+ immune cells. Macrophages (mean, 50.7%) and T cells (mean, 28.7%) were the predominant leukocytes, followed by NK cells, dendritic cells, B cells, and neutrophils. The immune cell composition within the TIME exhibited heterogeneity, with distinct patterns observed between functioning and non-functioning pitNETs. Functioning pitNETs displayed fewer macrophages (28.9% vs. 62.9%) and more T cells (44.9% vs. 19.6%) compared to non-functioning pitNETs. Subgroups within functioning (somatotroph, mammosomatotroph, lactotroph) and those within non-functioning pitNETs (null-cell, gonadotroph, corticotroph) shared similar immune profiles, respectively. PIT-1 lineage pitNETs demonstrated a T cell-dominated pattern, while SF-1, T-PIT, and null-cell lineage pitNETs exhibited macrophage predominance. In functioning pitNETs, macrophage abundance negatively correlated with invasiveness, Ki-67 index, and recurrence, while CD4 T cells showed positive correlations. Further unsupervised clustering identified 27 subpopulations of intratumoral immune cells, with some serving as critical predictors of tumor behavior. Our study provides a comprehensive single-cell immune profile of pitNETs, revealing distinct features across subtypes and targeted therapeutic implications.
TMIC-03. CARD9 BLOCKADE OFFERS A NEW OPPORTUNITY TO REPROGRAM TUMOR-ASSOCIATED MACROPHAGES IN GLIOBLASTOMA
Authors: Hofstatter Azambuja Juliana , Yerneni Saigopalakrishna , Maurer Lisa , Crentsil Hannah , Debom Gabriela , Klei Linda , Smyers Mei , Sneiderman Chaim , Schwab Kristina , Acharya Rajesh , Wu Yijen Lin , Ekambaram Prasanna , Hu Dong , Gough Pete , Foley Kevin , Bertin John , Melnick Ari , Kohanbash Gary , Bao Riyue , Lucas Peter , McAllister-Lucas Linda 
Published: November 2024

Abstract

BACKGROUND
Glioblastoma (GBM), one of the deadliest primary tumors of the central nervous system, is characterized by a highly immunosuppressive tumor microenvironment (TME). Tumor-associated macrophages and microglia (TAMs) are a dominant population of immune cells in the GBM TME and substantially contribute to immunosuppression, tumor progression, and treatment resistance. Elucidating the molecular mechanisms underlying TAM behavior is crucial to the development of effective immuno-therapeutic strategies for treating GBM. The adaptor protein, Caspase Recruitment Domain-containing protein 9 (CARD9) is primarily expressed in myeloid cells and its activation triggers assembly of the CARD9-BCL10-MALT1 (CBM) complex, which then promotes activation of NF-κB and/or MAPK pathways. The aim of this study was to investigate the role of the CBM complex in the GBM TME and assess its potential as a therapeutic target.

METHODS/RESULTS
In silico analyses revealed that GBM tumors demonstrate increased CARD9 and MALT1 expression in comparison to non-tumor brain tissue, with CARD9 expressed only within the myeloid compartment. Using co-culture, scratch wound, and transwell assays, we found that GBM tumor cells induce macrophage M2 polarization and migration via a mechanism that is dependent on CARD9/MALT1 signaling within macrophages. scRNA-Seq and flow-cytometric analysis of orthotopic syngeneic immunocompetent GBM tumor models revealed that the GBM TME is dominated by macrophages. Disruption of MALT1 protease activity within the TME leads to reduced tumor infiltration by immunosuppressive TAMs, remodeling of TAMs toward an immunoreactive anti-tumor phenotype, and improved survival of GBM-bearing mice. Additionally, we found that tumor growth was abrogated when GBM-bearing mice were treated with either a MALT1-protease inhibitor or a CARD9 inhibitor.

CONCLUSIONS
Our study suggests that blockade of the CARD9-MALT1 signaling axis impairs GBM-induced macrophage recruitment and M2 polarization and inhibits tumor progression. These findings nominate the CARD9-MALT1 signaling axis as a new target for TAM-directed immunotherapy for the treatment of GBM.
TMIC-05. AGING-SPECIFIC MICRORNA EXPRESSION SIGNATURE IN ELDERLY GLIOBLASTOMA
Authors: Yamashita Daisuke , Ohtsuka Yoshihiro , Takeda Haruna , Kusakabe Kosuke , Nishikawa Masahiro , Suehiro Satoshi , Inoue Akihiro , Watanabe Hideaki , Kondo Toru , Motohoshi Hozumi , Kunieda Takeharu 
Published: November 2024

Abstract

PURPOSE
The rise in aging population worldwide is increasing death from cancer, including glioblastoma. MicroRNAs (miRNAs/miRs) are small non-coding RNAs that mediate the posttranscriptional silencing of specific target mRNAs and that are currently recognized as important regulators of tumorigenesis and development. Here, we explore the impact of brain aging and aging-specific miRNAs on elderly glioblastomas.

METHODS
We comprehensively analyzed miRNAs expression using the TCGA dataset and identified miRNAs that are specifically expressed in elderly glioblastomas. To create the Ehime Glioma Genome Atlas (EGGA), RNA sequencing was performed using tumor tissues from 8 glioblastoma patients (4 elderly and 4 non-elderly). First, we evaluated the impact of the identified miRNAs on prognosis using TCGA and CGGA datasets and searched for target genes of specific miRNAs using TargetScan. The expression patterns of the identified target genes were verified using EGGA, TCGA, and CGGA datasets.

RESULTS
We divided the TCGA dataset into elderly and non-elderly groups based on three ages (75 years-old, 70 years-old, and 65 years-old) and analyzed the expression of miRNAs in tumor tissues. There were 3 miRNAs that showed abnormalities (1 increased miRNA, 2 decreased miRNAs), and among these, miR-210 (increased expression) and miR-507 (increased expression) were identified as miRNAs related to prognosis. Next, we analyzed the expression of EGGA and identified 410 mRNAs (368 increased mRNAs, 42 decreased mRNAs) that showed significantly abnormal expression in the elderly group. The target genes searched using TargetScan were 4,048 genes for miR-210 and 4,704 genes for miR-507. When compared with the 410 genes identified using EGGA, PLA2G3, a target gene to miR-507, was identified. The expression of PLA2G3 was also specifically increased in elderly glioblastoma in the TCGA dataset, and it had a strong influence on prognosis.

CONCLUSION
Our results found an aging-specific miRNA “miR-507” and its target gene “PLA2G3” that suggested as potential new therapeutic target molecules for improving the prognosis of elderly glioblastomas.
TMIC-06. TUMOR ASSOCIATED MACROPHAGES DRIVE TUMOR PROGRESSION AND ARE TRANSCRIPTIONALLY SHAPED BY HISTONE MUTATIONS IN DIFFUSE MIDLINE GLIOMA
Authors: Ross James , Puigdelloses-Vallcorba Montserrat , Pinero Gonzalo , Soni Nishant , Thomason Wes , DeSisto John , Angione Angelo , Tsankova Nadejda , Castro Maria , Schniederjan Matthew , Wadhwani Nitin , Raju G Praveen , Morgenstern Peter , Becher Oren , Green Adam , Tsankov Alexander , Hambardzumyan Dolores 
Published: November 2024

Abstract
Little progress has been made to delineate the inflammatory microenvironment in pediatric high-grade glioma (pHGG) and diffuse midline glioma (DMG). We utilize molecularly defined human samples and immunocompetent mouse models to study how tumor location and genetic driver mutations influence the tumor microenvironment (TME). We first induced tumors of each pHGG/DMG molecular subtype (H3WT, H3G34R, H3.1K27M, H3.3K27M) into both the cortical hemisphere and midline of separate mice and performed survival studies and flow cytometry. The main driving factor shaping the immune landscape and survival is the driver mutation, not tumor location. Next, we performed single cell RNA sequencing on murine H3WT cortical pHGG, H3WT DMG, H3.1 and H3.3K27M DMGs, paired with multiplex flow cytometry. H3K27M DMGs have sparse T cell infiltration and limited T cell recruiting chemokine production. The main non-neoplastic cell type in all tumors was infiltrating myeloid cells and microglia. H3WT DMGs had the greatest myeloid cell and monocyte-derived macrophage (MDM) infiltration, while H3.3K27M DMGs were enriched for microglia. Disease associated gene signatures were found in tumor-associated macrophages (TAMs) that are found in other neurodegenerative diseases, marked by down-regulation of inflammatory signaling, interferon responses, and up-regulation of metabolism-related pathways. H3.3K27M DMGs were enriched for disease-associated TAMs. These gene signatures were then identified in human pHGG/DMG scRNA sequencing data. CD16 monocytes and microglia were enriched for diseased signatures, while CD14 monocytes were pro-inflammatory. We demonstrate that reprogramming this diseased signature in mice results in increased T cell infiltration and extension of survival in H3K27M DMG. Last, through pharmacologic inhibition of CCR1 and CCR5, we demonstrate preventing TAM infiltration in DMG results in enhanced survival, comparable to radiation therapy. Together, this work provides the foundation for developing immunotherapies targeted at specific subgroups of pHGG and DMGs, such as CAR-T-cell, oncolytic viral therapy, and checkpoint blockade.
TMIC-14. RAPID EARLY PROGRESSION IN GLIOBLASTOMA: A COMPREHENSIVE REVIEW OF CLINICAL, IMAGING AND HISTOPATHOLOGICAL FEATURES
Authors: Waqar Mueez , Roncaroli Federico , O’leary Claire , Forte Gabriella , Wright Jenny , Parikh Shefali , Sudell Lindsay , Coope David , Djoukhadar Ibrahim , Borst Gerben 
Published: November 2024

Abstract

BACKGROUND
In glioblastoma patients, Rapid Early Progression (REP) refers to tumour growth between the time of surgery and postoperative chemoradiotherapy. Despite its high incidence relatively little is known about it. The aim of this study was to characterise REP using a combination of clinical, imaging and histopathology data.

METHODS
Ethical approval was obtained. Supratentorial IDH-wildtype glioblastomas undergoing gross-total resection (GTR) between 2015-2021 were included. REP was defined as a nodular increase in enhancement located within or around the surgical cavity, occurring within 6 weeks of surgery, that was not accounted for by initial areas of diffusion-restriction. REP cases were propensity-score matched to controls on baseline characteristics. Imaging was compared using mean apparent diffusion coefficient (ADC) and T1-postcontrast radiomics. Tissue analyses included DNA methylation subtyping and immunohistochemistry for markers of T-cells (CD3), microglia (P2RY12) and proliferation (PHH3).

RESULTS
REP occurred in 8/60 GTR cases (13%) and these patients were matched to 16 controls. REP cases had a worse preoperative performance status (median Eastern Cooperative Oncology Group [ECOG] 2 vs. 1), overall-survival (p=0.038) and progression-free survival (p = 0.029). REP was more common in patients over 65 years (27%) and significantly fewer REP patients received radical postoperative chemoradiotherapy (p=0.023). REP and control cases were well matched with respect to preoperative T1-postcontrast radiomics and mean ADC in enhancing (p=0.99) and non-enhancing regions (p=0.67). There was no relative excess of any one DNA methylation subtype in REP cases. The two groups had a similar proportion of T-cells (p=0.81), but REP cases had a trend towards a higher proportion of microglia (31% vs. 17%; p=0.22), and a lower proliferation rate (3% vs. 9%; p=0.19).

CONCLUSION
REP cases had a worse performance status from diagnosis and received less radical postoperative chemoradiotherapy protocols compared to controls, yielding a significantly shorter median OS/PFS. Differences in immune landscape and proliferation rate should be further investigated.
TMIC-19. EXCESSIVE LIPID PRODUCTION SHAPES GLIOMA TUMOR MICROENVIRONMENT
Authors: Paul Aboubechara John , Maraqah Haitham , Abu-Asab Mones , Lee Han Sung , Aboud Orwa 
Published: November 2024

Abstract
Disrupted lipid metabolism is a characteristic of gliomas. This study utilizes an ultrastructural approach to characterize the prevalence and distribution of lipids within gliomas. This study made use of tissue from IDH1 wild type (IDH1-wt) glioblastoma (n=18) and IDH1 mutant (IDH1-mt) astrocytoma (n=12) tumors. We uncover a prevalent and intriguing surplus of lipids. The bulk of the lipids manifested as sizable cytoplasmic inclusions and extracellular deposits in the tumor microenvironment (TME); in some tumors the lipids were stored in the classical membraneless spheroidal lipid droplets (LDs). Frequently, lipids accumulated inside mitochondria, suggesting possible dysfunction of the beta-oxidation pathway. Additionally, the tumor vasculature has lipid deposits in their lumen and vessel walls; this lipid could have shifted in from the tumor microenvironment or have been produced by the vessel-invading tumor cells. Lipid excess in gliomas stems from disrupted beta-oxidation and dysfunctional oxidative phosphorylation pathways. The implications of this lipid-driven environment include structural support for the tumor cells and protection against immune responses, non-lipophilic drugs, and free radicals.
TMIC-20. UNLOCKING THE POTENTIAL OF HYPOXIA REDUCTION IN RESHAPING THE GLIOBLASTOMA TUMOR MICROENVIRONMENT FOR ENHANCED THERAPEUTIC SYNERGY
Authors: William Ivana , Huntoon Kristin , Lea Spencer , Bhanu Krithikaa Rajkumar , Hegde Shweta , Kim Betty , Curran Michael 
Published: November 2024

Abstract
Glioblastoma (GBM) tumors respond poorly to nearly all cancer therapies due to their highly immunosuppressive tumor microenvironment (TME). Hypoxia exacerbates this immunosuppression by upregulating the hypoxia-inducible factor (HIF) pathway in glioma-associated myeloid cells (GAMs) which suppressively polarizes them to maintain this immune “cold” state. This hypoxia-driven programming inhibits CD8+ T cell infiltration and effector function by inducing metabolic dysfunction, thereby increasing resistance to chemotherapy and T cell immune checkpoint blockade (ICB). Targeting hypoxia thus emerges as a promising strategy to overcome such resistance. Our study suggests that GBM hypoxia ablation can convert the immunosuppressive tumor microenvironment into a more pro-inflammatory one. Tumor hypoxia ablation using the hypoxia-activated prodrug Evofosfamide significantly enhances survival in both GL261 (p&lt;0.0001) and the checkpoint blockade-resistant CT2A murine GBM models (p&lt;0.01). Evofosfamide treatment boosts tumor infiltrating Ki67+ proliferative CD8+ T cells (p&lt;0.001) and heightens cytotoxicity, indicated by increased Granzyme B expression (p&lt;0.01). It also reduces the co-expression of exhaustion markers LAG-3 and TIM-3 (p&lt;0.001), signaling decreased T cell exhaustion. Antigen-specific CD8+ T cells from Evofosfamide-treated primary GBM tumors exhibit enhanced ex vivo killing capacity when co-cultured with GL261-OVA cells (p&lt;0.001). Furthermore, Evofosfamide enhances microglia proliferation and repolarizes them towards a pro-inflammatory state, marked by upregulation of M1 markers such as CD80 (p&lt;0.001) and downregulation of M2 markers like Arginase (p&lt;0.05). Hypoxia reduction also increases chemotherapy sensitivity, synergistically improving survival when combined with the blood-brain barrier-penetrating, immunogenic chemotherapy Berubicin (CT2A; vehicle MS=26d, Evo MS=36d, Berubicin MS=55d, Combo MS=70.5d). Future research will investigate the mechanisms underlying this shift towards a pro-inflammatory state, focusing on metabolic changes in CD8+ T cells and the impact of altered HIF pathway signaling on GAM polarization following hypoxia ablation. Understanding the therapeutic potential of reversing hypoxia-mediated immunosuppression could lead to novel combination therapies capable of overcoming resistance to both chemotherapy and immunotherapy in GBM.
TMIC-28. TITLE: AN IMMUNE-RELATED, SEX-SPECIFIC T-CELL SIGNATURE IN GLIOBLASTOMA MICROENVIRONMENT WITH PROGNOSTIC IMPACT
Authors: Romagnoli Giulia , Offi Martina , Capone Imerio , Tavilla Andrea , Canini Irene , Lapenta Caterina , Buccarelli Mariachiara , Giordano Martina , Tirelli Valentina , Sanchez Massimo , Fragale Alessandra , Giannetti Stefano , Ceccarelli Giovanni Maria , Bonaventura Rina Di , Doglietto Francesco , Olivi Alessandro , Lauretti Liverana , Biffoni Mauro , Ricci-Vitiani Lucia , Pallini Roberto , Gabriele Lucia , D’Alessandris Quintino Giorgio 
Published: November 2024

Abstract

BACKGROUND
Glioblastoma, IDH-wildtype (GBM), is the most prevalent and aggressive primary brain cancer with a poor prognosis. Immune checkpoint inhibitors (ICIs) have been explored in GBM with limited success, highlighting the need for a better understanding of the tumor microenvironment (TME). This study investigated whether the expression of specific immune checkpoints on tissue-resident memory T cells (Trm) predicts patient outcomes.

METHODS
In a single cohort observational study, tumor samples from 45 histologically confirmed GBM patients were processed to obtain single-cell suspensions. Multiparametric flow cytometry was used to analyze the correlation of Trm phenotypes with overall survival (OS) and progression-free survival (PFS). Univariate and multivariate analyses were conducted to assess the prognostic significance of Trm subsets.

RESULTS
Low frequency of exausted Trm expressing programmed cell death protein 1 (PD1) and T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) was associated with better clinical outcomes. Multivariate analysis identified low CD8+CD103+PD1+TIM3+ Trm and Karnofsky performance status (KPS) ≥70 as the most significant independent prognostic factors for longer OS (hazard ratios—HR [95%CI]: 0.14 [0.04–0.52] p &lt; 0.001, 0.39 [0.16–0.96] p = 0.04, respectively). Additionally, younger patients (&lt;63 years) and males had distinct immune profiles affecting prognosis. Notably, the proportion of exausted CD8+CD103+PD1+ Trms had a prognostic correlate only in male patients, consistent with findings by other groups on the existance of gender-specific immune TME in GBM.

CONCLUSIONS
Further exploration of Trm-based immune profiling has the potential to shed light on GBM resistance to ICIs and to help in personalizing treatment strategies.
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

Abstract
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.