bluuebunny/crossref_metadata_2025_split huggingface dataset:
OS08.7.A STIMULATED RAMAN HISTOLOGY FOR INTRAOPERATIVE DIAGNOSIS IN PEDIATRIC BRAIN TUMORS
Authors: Kiesel B , Körner L , Makolli J , Vogel C , Haberler c , Dorfer C , Widhalm G 
Published: October 2024

Abstract

OBJECTIVE
Intraoperative frozen sections for neuropathological assessment is an essential tool in pediatric neurosurgical tumor resection. However, preparation as well as analysis of the tumor tissue can take as long as 45 minutes. Recently, stimulated Raman histology was introduced as a novel technique to provide a rapid high-resolution digital image of an unprocessed tissue sample directly in the operating room. The aim of this study was to evaluate the use of stimulated raman histology during pediatric brain tumor surgery.

METHODS
All patients aged 18 years or younger who underwent a biopsy or resection of a suspected tumor lesion were included in the current study. Intraoperatively, tissue samples of the suspected tumor lesion were collected. One sample was prepared and sent to the neuropathology department and a conventional frozen section was performed. Additionally, a sample was used for stimulated raman histology analysis directly in the operating room. In a further step, a tool was applied to provide a histopathological diagnoses using artificial intelligence. Conventional intraoperative frozen section and images obtained using stimulated raman histology were compared and analyzed.

RESULTS
In total 55 patients were included. The median age of our patient cohort was 9 years and included 25 female and 30 male patients. In all cases stimulated raman histology showed comparable images as the conventional frozen sections. The most common histopathological diagnosis was pilocytic astrocytoma followed by diffuse glioma, Medulloblastoma and Ependymoma. In 25 cases diagnosis using artificial intelligence was available and applied. In 50% the provided diagnosis was confirmed by histopathological assessment. In the other half of the cases AI diagnosis was not correct.

CONCLUSION
Stimulated raman histology represents a useful rapid intraoperative tool to obtain images comparable to conventional frozen sections and thus provide important information for the neurosurgeon to optimize surgical management. The AI tool may in future represent a helpful tool to provide a rapid intraoperative diagnosis.
OS09.5.A UNEXPECTED FUNCTIONAL ROLE OF GLYCOCALYX ENCAPSULATION DURING GBM METABOLIC ADAPTATION OPENS AVENUES FOR NEW TREATMENT CONCEPTS
Authors: Bång-Rudenstam A , Cerezo-Magaña M , Gonçalves de Oliveira K , Governa V , Talbot H , Kjellen L , Tykesson E , Malmström A , van Kuppevelt T , Forsberg-Nilsson K , Bengzon J , Belting M 
Published: October 2024

Abstract

BACKGROUND
The inherent adaptive capacity of GBM to metabolic stress represents a key clinical challenge, and the underlying mechanisms remain ill-defined. Our lab focuses on the emerging role of lipid metabolism in cancer cell stress adaptation. We have previously found increased scavenging of lipid particles, including extracellular vesicles (EVs) and lipoproteins, during acute stress, further resulting in a lipid droplet (LD) storage phenotype. Here, we propose a new mechanistic link between chondrotin sulfate proteoglycan (CSPG) remodelling, extracellular lipid scavenging, and LD formation that together serve to fine tune intracellular lipid metabolism to escape ferroptosis.

MATERIAL AND METHODS
We have comprehensively profiled GBM tissues and cells during different acidic stress adaptation conditions, including freshly resected GBM specimens, primary GBM cultures, and established GBM cell-lines. Methods/analyses include: Multiomics (RNA, proteome, glycome), laser capture microdissection for spatial profiling, snRNA-seq, immunophenotyping by FACS and imaging, and in vitro treatment studies (in 2D and 3D) with live imaging of cytotoxicity and ferroptosis. Mouse GBM models were employed for in vivo treatment studies.

RESULTS
We provide first evidence of a functional role of cell-surface CSPGs during GBM adaptation to metabolic acidosis. Substantial CSPG induction coincides with LD formation in a process dependent on extracellular lipids and acidification. Specifically, CSPG encapsulation of stressed GBM cells acts as a shield against excessive lipid particle scavenging while LDs consitute an intracellular sink for lipid storage. Based on these findings, we introduce combined targeting of CSPGs and LDs as a strategy to challenge the stressed tumor niche. Concomitant disruption of CSPG and LD formation unleashes a metabolic vulnerability in acidic cells driven by uncontrolled lipid uptake and peroxidation, mitochondrial disintegration, and ferroptotic death.

CONCLUSION
In conclusion, this study identifies a potentially targetable adaptative mechanism in the treatment resistant, acidic niche of GBM. We propose that cancer cell escape from acidic stress involves the induction of CSPGs - providing a shield against the lipid rich tumor microenvironment - and LDs - forming an intracellular lipid sink. Combined targeting of CSPG and LD formation to induce ferroptosis may offer new therapeutic opportunities in GBM and other solid tumors.
OS12.5.A IMPROVING HEALTH EDUCATION FOR BRAIN TUMOR PATIENTS AND RELATIVES THROUGH ANIMATED AND VISUAL INFORMATION
Authors: Baas-Thijssen M C , Nogarede-Bloemendaal C O , Docter-Kerkhof C S 
Published: October 2024

Abstract

BACKGROUND
Brain tumor patients interact with a wide range of healthcare professionals. It is important that they receive simple and unequivocal information about what awaits them. This contributes to shared decision making, an individual treatment plan and informed consent. Providing information becomes challenging when people are communicatively vulnerable, i.e. when they are ill or experience intense emotions. A high number of brain tumor patients are communicatively vulnerable because they have cognitive deficits or language impairments. Information processing may become slower because of the tumor and/or treatment. In 2023 the neuro-oncology task group of OncoWest, a network in the west of the Netherlands, prioritized the improvement of health care education for patients with a primary brain tumor.

MATERIALS AND METHODS
Visual and spoken information combined was considered best for brain tumor patients, including those with low literacy. A graphics agency was approached to create animations and a project team was assembled. The team consisted of two nurses, a clinical linguist and a communication advisor. They devised the content and texts for three main topics: care process, treatments and consequences. Texts were written in B1, a language level understood by the majority of Dutch citizens. Other factors were also taken into account, such as length of sentences, use of active tense and total duration of the videos. The texts were then reviewed by specialists in the field of neuro-oncology, and patients. A voice actor finally did the voiceover. Clinical linguists gave intermediate feedback on the animation videos. The videos still seemed too complex and fast for individuals with aphasia. Therefore, an additional tool was developed for people with aphasia as to provide extra written information, illustrated by stills from the videos. A clinical linguist simplified the text and bolded important words.

RESULTS
Three animation videos were developed of about three minutes each, all freely accessible, with explanation and information about 1) the care process from initial complaints to diagnosis, 2) possible treatments surgery, radiotherapy, chemotherapy and best supportive care, 3) symptoms and consequences of the disease. Furthermore an interactive pdf was made available for patients with aphasia and could be printed.

CONCLUSION
We described the development of clear, easily accessible visual information for brain tumor patients. The information is now available for patients, including everyone around the patient, which will hopefully increase their understanding and health care process. We hope to promote and evaluate the use of these materials in the near future.
P01.01.A CHARACTERIZATION OF GLIOBLASTOMA’S MIGRATION HETEROGENEITY THROUGH A PATIENT-DERIVED 3D MODEL
Authors: Pujol-Castiblanque A , Savin T , Markaki A E , Mair R 
Published: October 2024

Abstract

BACKGROUND
Glioblastoma (GB) is an aggressive brain cancer with an average survival of 14.6 months. Effective treatment is hindered by GB’s plasticity and invasive phenotype. Little is known regarding the molecular mechanisms driving invasion heterogeneity.

MATERIAL AND METHODS
We developed a bioengineered model of brain-like matrix, which together with patient-derived spheroids, allows study of GB’s migration in vitro. Twenty patient-derived cell lines with different intrinsic (genomic, transcriptomic) characteristics in several extrinsic (extracellular matrix stiffness, hypoxia vs normoxia) conditions were tested.

RESULTS
Time-lapse video analysis identified recurrent migratory phenotypes across the cell lines. GB’s subtype- proneural, neural, classical, and mesenchymal- did not cluster cell lines with similar migratory phenotypes. An increase in matrix stiffness led to a switch in migratory phenotype in certain cell lines.

CONCLUSION
We have identified finite and periodic migration phenotypes of GB in different conditions.
P01.06.B GLIOMA STEM CELLS REMODEL ASTROCYTES TO FACILITATE GBM PROGRESSION VIA EXOSOMAL ZNF16 ACTIVATED TGF-Β SIGNALING AXIS
Authors: Dong J 
Published: October 2024

Abstract

BACKGROUND
Tumor-associated astrocytes (TAAs) play crucial promoting roles during tissue remodeling of glioma stem cells (GSCs), however, molecular mechanisms regulating astrocytes transformation, as well as glioblastoma progression by TAAs have not been fully clarified.

MATERIAL AND METHODS
Normal human astrocytes (NHAs) were cultured in vitro and continuously treated with GSC-derived exosomes (GSC-exo). Cellular phenotypes of TAAs were analyzed, expression of TAAs associated markers TGF-β, CD44, and tenascin-C was assayed by Western blot. Bioinformatic prediction of upstream transcription factor of TGF-β was performed and validated by RT-PCR, dual-luciferase reporter assay. Cell-based assay of glioblastoma proliferation and chemo-resistance were performed through flow cytometric assay, Western blot and colony formation assay, respectively. A xenograft tumor model was applied to verify the role of exosomal ZNF16 activated TGF-β signaling axis in vivo.

RESULTS
Notably, under the influence of GSC-exo, NHAs undergo transformation into tumor-associated astrocytes (TAAs) within three days, expressing hallmark surface markers such as TGF-β, CD44, and Tenascin-C. The transcription factor zinc finger protein 16 (ZNF16) was directly bound to the TGF-β promoter region and enhanced TGF-β expression.This transformation was associated with upregulation of TGF-β in NHAs activated by GSCs exosomal ZNF16. TGF-β is a direct downstream target of ZNF16 in TAAs. Transformed TAAs exhibit morphological changes, enhanced proliferative and migrative capacities, as well as contributing to aggressiveness and chemo-resistance of glioblastoma. In vivo studies disclosed that targeting on GSC-exosomal ZNF16 or TGF-β can suppressive transformation of TAAs and inhibiting their tumor promoting role on glioblastoma progression.

CONCLUSION
Understanding the intricate mutual interactions between GSCs and astrocytes in glioblastoma microenvironment can shed light on new therapeutic strategy on disrupting GSCs-TAAs crosstalk against glioblastoma progression.
P01.12.A PERSISTENT GENETIC AND EPIGENETIC CHANGES ARE INDUCED BY INVASION STIMULI IN GLIOBLASTOMA CELLS
Authors: Müller T , Schreiner S , Cialini C , Salcedo U M , Mittelbronn M , Plate K H , Steinbach J , Hau A 
Published: October 2024

Abstract

BACKGROUND
One key biological challenge in glioblastoma (GB) is the diffuse invasion of GB cells into the brain parenchyma beyond the margins of even supramaximal resection strategies. Various cell-intrinsic and extrinsic factors have been shown to regulate GB invasion, but it is unknown whether invasive GB cells acquire a persistent distinct genetic and epigenetic profile in response to environmental cues.

MATERIAL AND METHODS
Highly invasive isogenic subpopulations of GB cells (GBinv+ cells) were generated by serial invasion through matrix-coated transwell membranes. RNA sequencing and array-based DNA methylation profiling of control and GBinv+ cells were performed. Differentially expressed genes (DEGs) and differentially methylated probes (DMPs) were analysed using DESeq and RnBeads R package, respectively. Functional correlations of DEGs and DMPs were analysed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Candidate genes were validated using TCGA-LGG/GBM datasets and experimentally confirmed by genetic modulation of gene expression changes and applying classical in vitro invasion assays as well as the GLIoma Cerebral Organoid (GLICO) model for complex ex vivo tumor cell invasion analysis.

RESULTS
In classical in vitro invasion assays, the invasion potential of GBinv+ cells were more than 10-fold increased relative to the isogenic control cells baseline (p &lt; 0.0001, students t-test). Increased invasion was also demonstrated using the GLICO model. GBinv+ cells were found to have unique transcriptomic and DNA-methylation profiles that persisted for &gt;2 weeks after removal of the stimulus. Genetic deletion of candidate genes identified by profiling reduced invasive properties.

CONCLUSION
Our results indicate that the invasive sub-population of GB cells is characterized by a specific genetic and epigenetic profile and has enduring functional properties. The functional validation of the identified genes associated with invasion underscores their clinical relevance and suggests they may represent interesting new targets for experimental therapies.
P02.04.B CANCER-ASSOCIATED FIBROBLASTS IN LUNG CANCER BRAIN METASTASES: EFFECT ON CANCER CELL MIGRATION AND INVASION, AND MONOCYTE RECRUITMENT AND DIFFERENTIATION
Authors: Vymolova B , Smetana T , Pfeiferova L , Sachova J , Kolar M , Ternerova N , Vymola P , Svablova T , Houdova Megova M , Busek P , Sedo A 
Published: October 2024

Abstract

BACKGROUND
Brain metastases (BrM) are a frequent complication of lung cancer with dismal prognosis. The presence of cancer associated fibroblasts (CAF) was recently described in the BrM microenvironment, but their engagement in BrM biology is largely unknown. In this study, we evaluated the effect of CAF derived from lung cancer brain metastases (BrM-CAF) on cancer cells and the recruitment and differentiation of monocytes.

MATERIAL AND METHODS
Patient-derived BrM-CAF and cancer cells (BrM-CC) were isolated from lung cancer BrM. Normal fibroblasts were isolated from subgalear connective tissue. Monocytes were isolated from healthy donors’ peripheral blood. Patient-derived cell cultures were characterized using immunocytochemistry and RNA expression profiling. A transwell assay and a 3D spheroid-based assay were used to assess migration and invasion, respectively; cell growth was quantified using a kinetic label-free cell counting assay. Monocyte differentiation was evaluated by flow cytometry.

RESULTS
BrM-CAF expressed canonical fibroblast markers and their fibroblast-like phenotype was verified by RNA expression profiling. BrM-CC expressed epithelial markers. Conditioned media from BrM-CAF stimulated the migration of BrM-CC more than conditioned media from normal fibroblasts. In the invasion assay, the cancer cell invasive area was bigger in the presence of BrM-CAF; in addition, we observed a different pattern of invasion in BrM-CAF-containing spheroids, with more protrusions being formed. Direct co-culture with BrM-CAF diminished cancer cell proliferation. BrM-CAF conditioned media induced migration of monocytes. In direct co-culture with BrM-CAF, monocytes acquired a differentiated phenotype with both M1-like and M2-like features similar to that of tumor associated macrophages.

CONCLUSION
Using patient-derived cultures, we show that BrM-CAF promote cancer cell migration and invasion but decrease their proliferation. Moreover, BrM-CAF can contribute to the recruitment of peripheral monocytes and their differentiation into tumor-associated macrophages. Taken together, these results demonstrate the role of BrM-CAF in shaping the brain metastatic microenvironment.

FUNDING
This research was funded by the Charles University grant 342522; project NU22-03-00318 of Ministry of Health of the Czech Republic, Program Cooperatio, research area,,Oncology and Haematology“; Ministry of Education, Youth and Sports of the Czech Republic - LM2023053 of EATRIS-CZ and project National Institute for Cancer Research (Programme EXCELES, ID Project No. LX22NPO5102) by the European Union - Next Generation EU.
P02.08.A HERV-W ENVELOPE PROTEIN IS PRESENT IN MICROGLIAL CELLS OF THE HUMAN GLIOMA TUMOR MICROENVIRONMENT AND DIFFERENTIALLY MODULATES NEOPLASTIC CELL BEHAVIOR
Authors: Reiche L , Plaack B , Lehmkuhl M , Weyers V , Gruchot J , Picard D , Perron H , Remke M , Reifenberger G , Küry P , Knobbe-Thomsen C , Kremer D 
Published: October 2024

Abstract

BACKGROUND
Glioma is the most common and aggressive primary tumor of the central nervous system (CNS). With regard to its still unclear etiology, several recent studies focused on human endogenous retroviruses (HERVs) as potential new pathogenic factors in various neurological diseases. Although HERVs account for up to 8 % of the human genome, these retroviral elements are epigenetically silenced but can be reactivated by environmental factors such as infection with modern viruses. The resulting production of viral particles and/or proteins exerts effects on cellular processes such as inflammation, proliferation and migration in neurological diseases such as amyotrophic lateral sclerosis (ALS), schizophrenia, chronic inflammatory polyneuropathy (CIDP) and multiple sclerosis (MS). In previous studies, we demonstrated that in MS, the human endogenous retrovirus type-W envelope protein (HERV-W ENV) interferes with lesion repair through the activation of microglia (MG), the innate myeloid immune cells of the CNS. In this study, we investigated whether HERV-W ENV is expressed in gliomas. In particular, we aimed to understand how and to what extent HERV-W ENV modulates neoplastic cell behavior.

MATERIAL AND METHODS
We used immunohistochemical staining to detect HERV-W ENV in human gliomas. The mRNA expression of HERV-W ENV in tissue samples of human gliomas was quantified via qRT-PCR. Using the human glioblastoma cells T98, A172 and LN229 we investigated the effects of HERV-W ENV on various molecular and cellular markers, including gene and protein expression, proliferation and migration.

RESULTS
We show that HERV-W ENV is present in the microglial cells of the tumor microenvironment (TME) of human glioma. It modulates the behavior of human glioblastoma (GBM) cell lines in GBM/MG cocultures by altering their gene expression, secretome, morphology, proliferation, and migration properties and could thereby contribute to key tumor properties.

CONCLUSION
This study shows that HERV-W ENV is a relevant player in the interplay between glioma and microglial cells within the tumor microenvironment. In vitro evidence suggests that HERV-W ENV modulates the drivers of glioma progression via microglia. Whether this can be used therapeutically by blocking HERV-W ENV with the monoclonal antibody temelimab will have to be investigated in future studies.
P02.09.B HYPOXIA MODULATES DIFFUSE ASTROCYTOMA TUMOR MICROENVIRONMENT THROUGH CELL-TYPE-DEPENDENT RESPONSES
Authors: Tiihonen A , Salonen I , Koivisto I , Ritamäki A , Jaatinen S , Hyvärinen T , Kreutzer J , Mohammadlou M , Valkonen M , Ruusuvuori P , Parkkila S , Kallio P , Hagman S , Kesseli J , Ravi V M , Haapasalo H , Jukkola A , Joseph K , Rautajoki K J 
Published: October 2024

Abstract

BACKGROUND
Diffuse astrocytomas, especially glioblastomas (GBs), are aggressive brain tumors with a poor prognosis despite the efforts to improve their treatment. In diffuse astrocytomas, myeloid immune cells, notably monocyte-derived macrophages and brain-resident microglia are pivotal in the immunoregulation of tumor microenvironment (TME). GBs, characterized by higher macrophage frequencies, often exhibit hypoxia in the TME. In this work, we investigated how hypoxia affects the regulation of myeloid immune cells.

MATERIAL AND METHODS
We analyzed 222 diffuse astrocytoma patient samples using multiplex immunohistochemistry, 45 GBs with single-cell RNA sequencing (SCS) data, and 30 diffuse astrocytoma samples using spatial transcriptomics. The resulting data was analyzed with QuPath as well as R and Python-based tools and scripts.

RESULTS
Our findings reveal that hypoxia generates distinct spatial and gene expression responses in macrophages and microglia. Microglia decrease in highly hypoxic areas, while macrophages increase gradually compared to normoxia. In SCS data, macrophages show the highest proportion of cells under hypoxia, and the responding differentially expressed genes in macrophages and microglia are associated with different biological processes. Our results are further validated with spatial transcriptomics and cell culture models.

CONCLUSION
Hypoxia is significantly shaping the TME and immunosuppression in diffuse astrocytomas.