bluuebunny/crossref_metadata_2025_split huggingface dataset:
P02.15.A INVESTIGATING THE ROLE OF CELLULAR SENESCENCE IN BRIDGING GLIOBLASTOMA AND ALZHEIMER’S DISEASE
Authors: Krause E , Greutter L , Romanovskaia D , Stepper P , Wöhrer A 
Published: October 2024

Abstract

BACKGROUND
With changing demographics, age-related diseases like neurodegenerative disorders and cancer are becoming increasingly prevalent. We previously demonstrated that over 50% of glioblastoma (GB) patients show Alzheimer’s Disease (AD)-like changes in the tumor-adjacent cortex. However, whether these diseases are biologically linked remains unclear. Here, we investigate cellular senescence, a hallmark of aging, as a shared mechanism.

MATERIAL AND METHODS
We utilized single cell and single nucleus RNA sequencing datasets from 110 GB patients (GBmap core atlas) and 89 individuals with varying stages of AD (SEA-AD MTG atlas). Following data integration, we assessed senescent cells using three established gene lists, performed differential gene expression and conducted gene set enrichment analysis. Senescence scores were compared across different cell types and patients. Co-expression modules with senescence-associated genes were identified using weighted gene co-expression network analysis (WGCNA). Quantitative neuropathological analysis of published measurements (Iba1, AT8, 6E10) complemented the molecular findings.

RESULTS
Senescence was found in both GB and AD patient cells including cell types of the microenvironment. Notably, the variability in scores per patient was significantly higher in GB as compared to AD cell types, indicating greater inter-patient heterogeneity. Microglia were specifically enriched for senescence gene sets among glial cells. Subset analysis of microglia through data harmonization identified a proinflammatory GB microglia subtype that shared high similarity with AD microglia and had highest senescence scores. Notably, the increase in senescent microglia was associated with progression to advanced disease stages in both diseases. WGCNA identified 3 consensus modules of senescence-associated genes that were coexpressed with disease-specific genes, like PTEN implicated phosphorylation in the AD module and SPP1 for extracellular matrix remodeling in the GB module. All senescence associated modules showed increased expression in more advanced disease stages. Quantitative analysis of immunohistochemistry measurements in the AD dataset confirmed that samples with a high senescence score showed a significantly higher density of tau pathology and an altered microglia morphology.

CONCLUSION
Our study identifies cellular senescence as one connection between GB and AD pathology by utilizing atlas-level transcriptomic datasets. Particularly microglia upregulate senescence signatures with disease progression. The co-expression of senescence-associated genes within disease-specific modules underscores the complexity of senescence in this context.
P02.18.A MOLECULAR CHANGES UNDERLYING DECAY OF SENSORY RESPONSES AND ENHANCED SEIZURE PROPENSITY IN PERITUMORAL NEURONS
Authors: De Santis E , Tantillo E , Scalera M , Meneghetti N , Cerri C , Menicagli M , Mazzoni A , Costa M , Mazzanti C , Vannini E , Caleo M 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma growth impacts on the structure and physiology of peritumoral neuronal networks, altering the activity of pyramidal neurons which drives further tumor progression. It is therefore of paramount importance to identify glioma-induced changes in pyramidal neurons, since they represent a key therapeutic target.

MATERIAL AND METHODS
We longitudinal monitored visual evoked potentials after the orthotopic implant of murine glioma cells into the mouse occipital cortex. With laser microdissection, we analyzed layer II-III pyramidal neurons molecular profile and with local field potentials recordings we evaluated the propensity to seizures in glioma-bearing animals with respect to control mice.

RESULTS
We determine the time course of neuronal dysfunction of glioma-bearing mice and we identify a symptomatic stage, based on the decay of visual response. At that time point, we microdissect layer II-III pyramidal neurons and evaluate the expression of a panel of genes involved in synaptic transmission and neuronal excitability. Compared to the control group, peritumoral neurons show a decrease in the expression of the SNARE complex gene SNAP25 and the alpha1 subunit of the GABA-A receptor. No significant changes are detected in glutamatergic (ie, AMPA or NMDA receptor subunit) markers. Further reduction of GABA-A signaling by delivery of a benzodiazepine inverse agonist, DMCM (methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate) precipitates seizures in 2 mouse models of tumor-bearing mice.

CONCLUSION
These studies reveal novel molecular changes that occur in the principal cells of the tumor-adjacent zone. These modifications may be therapeutically targeted to ameliorate patients’ quality of life.
P02.20.A NICHE-DEPENDENT MODES OF IMMUNE CELL TRAFFICKING IN GLIOBLASTOMA OFFER TARGETS FOR NOVEL IMMUNOTHERAPIES
Authors: Sankowski R , Dalmau Gasull A , Prinz M 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma trigger systemic immune responses, resulting in elevated white blood cell counts and elevated temperatures, as the body attempts to combat tumor cells. However, glioblastoma reprograms immune cells to evade immune-mediated destruction and promote tumor growth. While targeted immunotherapies have shown promise in some cancers like melanoma, they have not been efficacious for malignant brain tumors, leading to significant societal costs due to high morbidity and mortality rates.

MATERIAL AND METHODS
Understanding immune cell trafficking is crucial for developing effective immunotherapies. We conducted spatially resolved single-cell analyses to investigate immune cell entry into glioblastoma. Integrating these data with multi-omic sequencing analyses of anatomically dissected specimens from glioblastoma-affected human brain border regions and tumor cores revealed distinct paths of immune cell trafficking into glioblastoma.

RESULTS
One path involves an ordered entry of mononuclear cells through the subarachnoid and perivascular spaces, guided by chemotactic cues. Cells in these regions display markers of immune activation, suggesting immune priming. Another path occurs at sites of vascular leakage due to hypoxia and necrosis, where a mix of mononuclear cells and neutrophils accumulate. These cells exhibit immunosuppressive transcriptomic programs, regulated by the phagocytosis-inducing transcription factor MITF and downstream metabolic changes controlled by PPAR-gamma. Ongoing analyses aim to identify pharmacological agents that can modulate immune cell reprogramming at hypoxic niches.

CONCLUSION
In summary, we have identified distinct modes of immune cell trafficking in glioblastoma. Chemotaxis-mediated trafficking via the brain border regions appears to prime immune cells, while entry at hypoxic niches is associated with immune suppression. Pharmacological agents shielding immune cells from immunosuppressive molecular cues in the tumor microenvironment show promise for glioblastoma immunotherapy.
P02.21.A PROGNOSTIC ROLE OF CD68 AND CD163 IN GLIOMAS
Authors: Petrescu G E D , Dragomir M P , Brehar F M , Gorgan R M 
Published: October 2024

Abstract

BACKGROUND
Tumor-associated macrophages (TAMs) have been demonstrated to play an important role in the growth and progression of multiple types of cancer, including glioblastoma. The aim of this study is to evaluate the distribution of CD68 and CD163 markers for TAMs in glioma samples and to determine their impact on survival.

MATERIAL AND METHODS
A tissue micro-array was performed using glioma samples from patients who underwent surgery at our institution. Diagnosis was established based on the WHO 2021 CNS classification. Thirty-six glioblastoma IDH-wt (GBM) and 15 oligodendroglioma, IDH mutant and astrocytoma, IDH mutant (CNS WHO grade 2 or 3) were included in the study. For comparison CNS WHO grade 2 or 3 samples were grouped. Immunohistochemical staining was performed for the detection of CD68 and CD163. CD68+ and CD163+ stainings were evaluated by counting the number of positive cells using QuPath (ver 0.4.4). For survival analysis the optimal cut-off method was used.

RESULTS
There was a statistically significant difference between the median CD68+ count in GBM vs. gr.2-3 (8.51 vs. 3.27, p =0.0009), and between the median CD163+ count (20.52 vs. 1.38, p&lt;0.0001). By using the Spearman test, we observed a positive correlation (0.595) across all glioma samples between CD68 and CD163 (p &lt; 0.0001). The Log-rank test showed increased survival in samples with low vs. high CD163+ count (median OS: 42 months vs 12 months, p = 0.0004) across all glioma samples. Similarly, there was a difference between the low (median OS: 34 months) and high (median OS: 17 months) CD68+ count, but without statistical significance (p = 0.11). A significant difference was also noted between samples with low count of CD68+ and CD163+ or one of the markers with high count compared to samples where both markers had a high count (median OS: 34 vs. 11.5 months, p = 0.0012).

CONCLUSION
Our findings reinforce the carcinogenic role of TAMs in glioblastoma, as well as their prognostic value, highlighting the possibility of targeted therapy against these targets.
P02.24.B THE IMPACT OF THE IDH1 R132H MUTATION ON MMP2 METHYLATION, EXPRESSION AND INVASION IN EXPERIMENTAL GLIOMAS AND HUMAN GBMS
Authors: Lenkiewicz A M , Ibragimova A , Ghosh M , Szadkowska P , Ellert-Miklaszewska A , Baluszek S , Jacek K , Castro M , Kaminska B 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma (GBM) is a highly diffusive tumor which restricts the efficacy of surgical resection and facilitates tumor recurrence. Matrix metalloproteinase 2 (MMP2) is the extracellular matrix protease that is activated by MMP14 expressed by microglia and plays a central role in tissue remodeling and tumor progression. The R132H mutation in isocitrate dehydrogenase 1 (IDH1R132H) is commonly observed in gliomas, results in hypermethylator phenotype and in GBMs is associated with better survival. The impacts of IDH1R132H on the tumor microenvironment of mIDH1/mATRX/mTP53 gliomas remains unexplored.

MATERIAL AND METHODS
We employed unique mouse glioma models which mimic human GBM pathology, coupled with high-dimensional technologies (CITEseq and spatial transcriptomics) to analyze and visualize the immune landscape in different gliomas. Additionally, we performed gelatin zymography, qPCR, wound healing assays, and DNA methylation qPCR techniques to validate the obtained results. MMP-2 expression/methylation was studied in the glioma TCGA dataset.

RESULTS
The expression and activity of Mmp2 were different in experimental gliomas with different IDH1 status. Spatial transcriptomics demonstrated that Mmp2 expression is localized within the IDH1 wild-type tumors and absent in IDH1 mutated ones. Gelatin zymography showed the presence of Mmp2 activity in extracts from IDH1 wild-type tumors. Methylation of Mmp2 gene promoter was increased and resulted in decreased Mmp2 expression in IDH1 mutated gliomas. The IDH1 wild-type gliomas showed more diffuse growth patterns (tumors were stained with Nestin antibody) whereas IDH1 mutant gliomas showed more constrained growth patterns. In the TCGA glioma dataset, methylation of the MMP2 gene promoter was increased which was associated with decreased MMP2 expression in IDH1 mutated gliomas.

CONCLUSION
We found that the IDH1 mutation results in hypermethylation of the Mmp2 gene promoter, leading to decreased Mmp2 expression and Mmp2 activity in experimental gliomas and human GBMs. Reduced Mmp2 activity and decreased tumor invasion result in more restricted tumor growth, which may facilitate resection, and radiotherapy, thereby improving patient survival. Studies were supported by National Science Center Poland grant 2020/39/B/NZ4/02683 (BK) and PASIFIC Call 1 PAS (MG).
P02.25.A TUMOR MICROENVIRONMENT (TME) VIS-À-VIS ANTI-VASCULAR TREATMENT IN GLIOBLASTOMA
Authors: Chen Z , Cai H , Ni X 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma (GBM) the most malignant primary central nerves system tumor, usually failed to postoperative treatment since tumor resistance to treatment. Most of Studies for anti-cancer resistance focus on tumor cell its self. Actually, tumor tissue is composed of tumor cells and surrounding matrix components. The components in tumor microenvironment (TME) work in coordination with each other to promote cancer initiation, progression, metastasis, and treatment resistance. Previously, we have found vasculogenic mimicry (VM), a vessel-like structure formed by highly invasive tumor cells, may contribute to anti-vascular resistance. Since TME includes non-cellular components such as extracellular matrix(ECM)and tumor-associated vasculature, as well as various cellular components such as activated tumor-associated fibroblasts, mesenchymal cells, tumor associated macrophages (TAMs), and pericytes. We further invested TME relating to anti-vascular resistance.

MATERIAL AND METHODS
First, we examined tenascin-c (TNC) expression, an extracellular protein, and correlated with VM formation in glioma cell lines as well as clinical samples. Since TNC is composed of 2 domains (EGF-like and fibronectin III), we further examined function of these domains affecting on VM formation in glioma cell lines. Second, we examined association of TAMs with angiogenesis in GBM, and further search possible molecular mechanism.

RESULTS
The expression of TNC increased with the WHO grade of glioma, and the most abundant in GBM, which correspondence to existence of VM structure. Knockdown TNC expression resulted significant reducing the ability of VM formation. Treatment of exogenous TNC protein can enhance the ability of VM formation of glioma cells. The over expression of the EGF-like domain or the full-length TNC in glioma cells revealed significant enhancing VM formation ability. In contrast, over expression of the fibronectin III domain of TNC did not alter VM formation. Furthermore, over expression of the EGF-like domain of TNC or full-length TNC in glioma cells increased the phosphorylation levels of downstream signaling pathways of EGFR. When checked TAMs, we revealed that PTEN deficient GBM may secrete abundant Gal-9, and recruit plenty of TAMs. TAMs may secrete vascular endothelial growth factor A (VEGFA) stimulating angiogenesis and and supporting glioma growth. Moreover, α-lactose through down-regulating VEGFA expression, inhibited glioma angiogenesis.

CONCLUSION
Our findings by searching tumor microenvironment of glioma, may suggest novel antivascularization strategies through TNC (an extracellular protein in ECM) and TAMs.
P04.02.A DISCOVERY OF NEW METABOLIC PATHWAYS IMPLICATED IN THERAPY RESISTANCE IN GLIOBLASTOMA (GBM)
Authors: Cingöz A 
Published: October 2024

Abstract
Glioblastoma stands as the most prevalent and aggressive primary brain tumor. The current treatment regimen involves a combination of radiotherapy and chemotherapy post-surgical tumor resection. However, for most patients, tumor recurrence transpires with a more aggressive phenotype. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds promise as it selectively triggers apoptosis in tumor cells, rendering it an attractive therapeutic option. Nonetheless, numerous tumor cells, glioblastoma included, can develop acquired resistance against TRAIL therapy, yet the underlying mechanisms remain poorly elucidated. Apart from resistance to apoptosis, these mechanisms may also encompass non-genetic factors stemming from intracellular dynamics. In our previous research on generating models resistant to TRAIL, we observed differences in the expression of metabolic pathway genes in TRAIL-resistant glioblastoma cells. Our transcriptomic analysis revealed a positive correlation among pathways related to cellular metabolism in these resistant cells. Further examination of this gene family revealed common alterations across various cell lines. Additionally, to delve deeper into the role of cellular metabolism, we conducted in vivo CRISPR/Cas9 screening using a focused library targeting metabolism. We also compared mitochondria densities using MitoTracker dye between sensitive and resistant GBM cells, noting a significant increase in resistant cells. Using the Seahorse Extracellular Flux Analyzer, we measured cellular metabolism activity and observed higher oxygen consumption in resistant cells, indicative of elevated energy levels. Based on these preliminary findings, our study will undergo thorough genetic and metabolomic screening, promising significant insights into cancer metabolism. The identified target genes and metabolites could potentially serve as therapeutic targets for developing novel cancer treatments, particularly glioblastoma.
P04.04.B THE FUNCTIONS AND MECHANISMS OF OSGIN1 INVOLVED IN FERROPTOSIS RESISTANCE OF GLIOBLASTOMA
Authors: Huo L , Luo Z , Liang X , Du X 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma (GBM) is the most prevalent and aggressive primary brain tumor in adults, with an average survival time of less than 15 months despite treatment. Recurrence and chemotherapy resistance are major challenges, with ferroptosis emerging as a potential mechanism contributing to chemotherapy resistance. The role of oxidative stress-induced growth inhibitor 1 (OSGIN1) in GBM, particularly its localization and function, remains poorly understood, though it is associated with poor prognosis.

MATERIAL AND METHODS
We utilized bioinformatics to analyze OSGIN1 expression and GBM patient prognosis from the Cancer Genome Atlas (TCGA). Experimental approaches included C-terminal EGFP tagging of OSGIN1, overexpression, and knockdown experiments in GBM cells. We assessed the effects on cell proliferation, apoptosis, and ferroptosis sensitivity using CCK8 assays, flow cytometry, and lipid peroxidation sensors. The relationship between OSGIN1 and drug sensitivity was explored using data from the Cancer Therapeutics Response Portal (CTRP). Regulatory interactions between OSGIN1 and the cystine transporter SLC7A11 were investigated through polymerase chain reaction, Western blotting, dual luciferase assays, and chromatin immunoprecipitation.

RESULTS
High OSGIN1 expression correlates with poor prognosis in GBM. OSGIN1 does not localize with mitochondria in GBM cells nor induce apoptosis. Instead, OSGIN1-modulated cells exhibited altered ferroptosis sensitivity. Knockdown of OSGIN1 increased ferroptosis sensitivity, an effect reversible in OSGIN1-rescued cells. Moreover, OSGIN1 positively regulates SLC7A11 expression, impacting cystine uptake and ferroptosis resistance. Animal models confirmed that GBM cells overexpressing OSGIN1 are more resistant to ferroptosis.

CONCLUSION
OSGIN1 is a prognostic marker and potential therapeutic target in GBM. It regulates SLC7A11 expression and contributes to ferroptosis resistance, highlighting its role in the chemotherapeutic response. Targeting OSGIN1 could enhance GBM treatment efficacy by modulating ferroptosis sensitivity.
P05.01.A ATR INHIBITORS INCREASE THE ANTI-PROLIFERATIVE EFFECTS OF STANDARD TREATMENT ON PATIENT-DERIVED GLIOBLASTOMA CELLS
Authors: Lozinski M , Bowden N , Graves M , Day B , Stringer B , Fay M , Tooney P 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma is treated with surgery to remove as much as the tumour as possible then radiation therapy (RT) and temozolomide (TMZ) to cause extensive DNA damage in any remaining tumour cells, triggering cell death by apoptosis. However, glioblastoma cells respond by upregulating the DNA damage response (DDR) triggering DNA repair that contributes to treatment resistance. Progression then generally occurs rapidly leaving patients with a poor prognosis and survival. We previously showed that gartisertib, an inhibitor of ATM- and Rad3-Related protein (ATR), a serine/threonine kinase that triggers DNA repair, sensitises glioblastoma cells to TMZ and RT. We extend this investigation to brain-penetrant ATR inhibitors elimusertib (BAY1895344) and ceralasertib (AZD6738).

MATERIAL AND METHODS
Patient-derived glioblastoma cell lines were treated with a dose response of ATRi (elimusertib and ceralasertib) combined with a clinically relevant dose of TMZ (35uM) and/or RT (2Gy). A human astrocyte cell line was also treated with a dose response of single agent elimusertib and ceralasertib. Cells were incubated for 7 days and assessed for cell viability through an MTT assay or cell-cell Incucyte analysis.

RESULTS
Both elimusertib and ceralasertib as single agents reduced glioblastoma cell growth, with elimusertib being more potent compared to ceralasertib. Elimusertib had greater potency in causing cell death of the glioblastoma cell lines than a human astrocyte cell line. However, there was less difference between glioblastoma and astrocyte cell death when treated with ceralasetib. When combined with RT and/or TMZ, elimusertib once again was more potent in reducing glioblastoma cell growth compared to ceralasertib.

CONCLUSION
We have expanded our in vitro data showing that various ATR inhibitors (elimusertib, ceralasertib and previously gartisertib) are able to reduce the growth of glioblastoma cells in combination with RT and TMZ treatment. This provides further support for initiating a clinical trial of ATR inhibition in combination with standard treatment for patients with glioblastoma.
P06.05.B FLYDENTIFICATION - CHARACTERIZATION OF NOVEL MOLECULAR DRIVERS IN GLIOBLASTOMA BASED ON FUNCTIONAL GENOMICS SCREENING IN DROSOPHILA MELANOGASTER
Authors: Lewandowska O , Picard D , Hariri B , Klein T , Reifenberger G , Reiff T , Leprivier G 
Published: October 2024

Abstract
Glioblastoma is an extremely aggressive form of brain tumor. The median overall survival of patients is only 15 to 18 months, and the five-year survival rate is less than 10% despite aggressive multimodal treatment that includes total resection of the tumor followed by a combination of radio-, chemo- and Tumor Treating Fields (TTF)-therapy. Therefore, new therapeutic interventions are urgently needed. For this reason, it is essential to define novel therapeutic targets for this tumor entity. To this aim, we developed a combinatorial approach, termed “
FLY dentification”, to identify and characterize novel driver genes in glioblastoma. This pipeline combines bioinformatics analysis of patients proteomics data together with functional screening in Drosophila models of glioblastoma, and validation with human glioblastoma cell models. This approach allowed us to initially uncover the top 300 most overexpressed proteins in glioblastoma tissues using in silico preselection algorithms. By taking advantage of a Drosophila model of glioblastoma ‒ driven by overexpression of the oncogenic forms of EGFR and PI3K ‒ and using an RNAi approach we tested the functional contribution of 192 of the gene candidates to glioblastoma lethality in vivo. This targeted screening allowed us to identify 41 clinically and functionally relevant gene candidates. Focusing on the top candidates with no reported function in glioblastoma, we demonstrated that the DNA binding and chromatin remodeling DEK protein contributes to human glioblastoma tumorigenesis in vitro. Some of these findings will be validated using in vivo models of human glioblastoma. Together, the established “FLY dentification” pipeline represents a combinatorial approach designed to uncover previously unrecognized glioblastoma driver genes, which has the power to reveal novel biomarkers and therapeutic targets for this tumor type.