Nervous System Tumors Research Articles

CTIM-02. PIONEERING QUAD-TARGETING CAR T CELL THERAPY IN PEDIATRIC CNS TUMORS – ANALYSIS FROM THE INITIAL PATIENTS TREATED ON THE FIRST-IN-HUMAN PHASE 1 TRIAL BRAINCHILD-04

Abstract BACKGROUND BrainChild-04 is a first-in-human clinical trial of quad-chimeric antigen receptor (CAR) T cell therapy for children and young adults with central nervous system (CNS) tumors. This trial administers repeated locoregional CAR T cells targeting B7-H3, EGFR, HER2, and IL-13Ralpha2 (“quad-CAR T cells”), leveraging multi-antigen targeting to address the tumor heterogeneity of high-grade CNS tumors. METHODS The primary endpoints are feasibility and safety, and secondary endpoints are disease response and correlative studies of CAR T cell activity. The trial utilized a Bayesian Optimal Interval (BOIN) statistical design with three planned dose regimens(DR). There are 2 arms with weekly delivery for 3 weeks of a 4-week cycle:(A) –diffuse intrinsic pontine glioma (DIPG), (B) –non-pontine diffuse midline glioma (DMG) or other relapsed CNS tumors. RESULTS Enrolled patients include DMG N=6, DIPG N=5, other CNS tumors N=4. Of the 15 enrolled patients, 7 have been infused with 8 awaiting infusions. A total of 33 intracranial CAR T doses have been delivered, including Arm A DR 1 (N=1), Arm B DR 1 (N=3), DR2 (N=3). The most common adverse events have been grade 1-2 fever (7/7 patients), grade 1-3 headache (6/7), and grade 1-2 nausea/vomiting (6/7). There have been no DLTs and no cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity (ICANS). CTCAE and tumor inflammation-associated neurotoxicity are both being captured. All treated patients are alive with median follow up time post-initial infusion of 93(14-198) days. CAR T cells were detected by flow cytometric analysis of CSF post-infusion in 14/24 CSF samples. Radiographic response, CSF circulating tumor DNA, targeted mass spectrometry, and cytokine analysis will be presented. CONCLUSIONS Our preliminary experience suggests tolerability of locoregional delivery of quad-CAR T cells at doses currently evaluated. The trial remains ongoing and these data support continued evaluation of this product to better assess anti-tumor activity in patients with CNS tumors, including DIPG/DMG.

PATH-37. A NEW SUBTYPE OF DIFFUSE MIDLINE GLIOMA, H3 K27 AND BRAF/FGFR1 CO-ALTERED, EXHIBITS SPECIFIC BIOLOGICAL CHARACTERISTICS AND NEW THERAPEUTIC VULNERABILITIES

Abstract Diffuse midline gliomas (DMG) H3 K27-altered are incurable grade 4 gliomas and represent a major challenge in neuro-oncology. This tumor type is classified in four subtypes by the 2021 edition of the WHO Classification of the Central Nervous System tumors. However, we recently identified a new subtype of DMG by assembling a retrospective cohort of 60 adult and pediatric DMG cases harboring BRAF or FGFR1 mutations in addition to the H3K27M mutation or EZHIP overexpression. Comprehensive clinical, histological, radiological, and genomic, analyses allowed to identify distinct genotype-phenotype characteristics. Contrary to other DMG, these tumors occur more frequently in the thalamus (27% vs. 70% for BRAFV600E or 58% for FGFR1MUT), and in adults in the case of FGFRMUT tumors. Importantly, these patients display a longer overall survival with a median above three years. Unsupervised analysis of DNA methylation profiles regrouped these MAPK-altered DMG in a methylation cluster distinct from other DMG H3K27, but also lower-grade midline tumors driven by FGFR1 or BRAF mutations Additionally, this new DMG subtype harbors atypical radiological and histopathological profiles with calcification and/or a solid tumor component both for BRAFV600E and FGFR1MUT cases that can suggest this differential diagnosis. Further analyses of the transcriptome of these tumors compared to canonical DMG H3K27-altered showed an expression signature of senescence with activation of a TP53/CDKN1A axis, together with a strong upregulation of the PI3K/AKT/MTOR pathway. Our current modelling of the drug response using patient-derived models of these specific DMG will permit to rapidly prioritize treatment strategies. Additionally, our clinical experience in treating these patients suggests a higher response to everolimus and imipridone ONC201 in this specific subtype. In conclusion, DMG H3 K27 and BRAF/FGFR1 co-altered, represent a new subtype of DMG with distinct specific characteristics compared to canonical DMG H3K27 and data accumulated strongly support their separate stratification in clinical trials and specific therapeutic managements.

EXTH-37. ALLOSTERIC MITOCHONDRIAL CLPP AGONIST ONC206 ALTERS STRESS RESPONSE, METABOLIC AND EPIGENETIC PROFILES TO ELICIT ANTI-CANCER EFFICACY IN HIGH-GRADE GLIOMAS

Abstract Dordaviprone (ONC201) is a dopamine receptor D2/3 (DRD2/3) antagonist and allosteric ClpP agonist that has demonstrated durable responses in recurrent H3 K27M-mutant glioma patients. ONC206, a derivative of ONC201 with nanomolar potency that also targets DRD2/3 and ClpP, is in Phase I trials for central nervous system tumors. We characterized target relevance, human ClpP binding, in vitro efficacy, downstream signaling and response determinants associated with ONC206 in high-grade gliomas (HGG). Co-crystallization with ClpP that assembles as a tetradecameric complex revealed an allosteric ligand interaction with distinctions in the ONC206-ClpP overall conformation relative to the ONC201-bound or apo complex, including an increase in the resolved pore size and decreased complex height. ONC206 was more potent than ONC201 in cell-free human ClpP casein/peptide degradation assays). Accordingly, HGG cell lines and patient-derived cells exhibited increased sensitivity to ONC206 relative to ONC201 and generally required a shorter duration of exposure. Unlike DRD2, CRISPR-mediated ClpP knockout in HGG cell lines blunted ONC206 sensitivity. Metabolomics revealed elevated α-ketoglutaric acid, α-hydroxyglutaric acid, and glutaric acid. Proteomics indicated inhibition of multiple mitochondrial pathways including OXPHOS and TCA cycle. TCA cycle enzyme α-ketoglutarate dehydrogenase (KGDH) was inhibited in a ClpP-dependent manner. Western blotting showed downregulated ClpX, and upregulated ATF4/CHOP, H3 K27me3 and H3 K36me3. Next-generation sequencing of acquired resistance cell lines, which exhibited cross-resistance to ONC201 and ONC206, revealed diverse ClpP missense mutations distributed across various monomer interfaces. Both intrinsic and well as ONC206-stimulated ClpP proteolysis were mitigated by these mutations, which was congruent with an absence of the tetradecameric assembly. These ClpP mutations recapitulated resistance and, conversely, wildtype ClpP overexpression restored sensitivity. Thus, allosteric ClpP agonism is a key determinant of ONC206 activity in HGG by altering stress response, metabolic, and epigenetic profiles.

CNSC-34. SURGICAL INTERVENTION ASSOCIATION WITH THE DEVELOPMENT OF SUBSEQUENT DISSEMINATION IN CHILDHOOD DIFFUSE INTRINSIC PONTINE GLIOMAS (DIPG)

Abstract BACKGROUND Diffuse intrinsic pontine glioma (DIPG) is one of the most aggressive pediatric central nervous system tumors, and currently, there are no curative treatment options available. With the increasing application of molecular diagnostics, more and more DIPG patients are recommended to undergo surgery; however, its correlation with dissemination needs to be better understood. Hence, we conducted this cohort to analyze the predictors of subsequent metastasis in pediatric DIPGs. METHODS The final analysis included 142 pediatric (age ≤ 12) DIPG patients treated at Sanjiu Brain Hospital between January 2017 and September 2023. The data were retrospectively collected following the initial diagnosis. Patients were followed up for 6 months. The primary endpoint was the occurrence of subsequent metastasis. Univariable and multivariable logistic regression analyses were utilized to identify statistically significant predictors of subsequent dissemination. All statistical assessments were two-tailed, and only P < 0.05 was deemed to be statistically significant. RESULTS Among 142 patients, 14(9.9%) developed metastasis within the follow-up time. There were 77(54.2%) males and 65(45.8%) females. The median age was 7 years (ranging 1 - 12 years). The overall cohort demonstrated that surgery was the only predictor of dissemination both in univariable (OR 4.567, 95%CI 1.351 – 20.901, P = 0.024) and multivariable (OR 5.501, 95%CI 1.560 – 26.105, P = 0.014) analyses. However, subgroup analysis involving patients who received surgical intervention showed that biopsy was not superior nor inferior to resection in terms of relative risk for subsequent dissemination (16.7% vs. 15.8%). CONCLUSION Surgical intervention increases the relative risk of dissemination occurrence to four times more than those who did not receive surgery. Surgical intervention is crucial given the potential of molecular analysis leading to improved therapeutic options. Nonetheless, patients should be informed about the risks associated with surgery, including subsequent metastasis.

TMOD-07. DEVELOPMENT AND CHARACTERIZATION OF A SPINAL CORD DIFFUSE MIDLINE GLIOMA MODEL

Abstract Diffuse midline gliomas (DMGs) are very aggressive central nervous system tumors that occur mainly in children and adolescents. Most DMGs develop in the brainstem, but they can also be found in the thalamus and the spinal cord, the latter comprising 4% of all DMGs. Despite advances in current treatments, the outcome for DMG patients remains extremely poor. The success of immunotherapy in other tumors encourages its translation to DMGs, for which the understanding of the tumor immune microenvironment (TIME) is imperative. The field counts with several murine DMG models in the pontine and thalamic locations. However, there is a paucity of spinal cord models. Thus, in this work, we have generated an orthotopic syngeneic model of H3K27M spinal cord DMG by injecting the tumor cells directly into the spinal cord under the T2 vertebra. We monitored tumor growth by bioluminescence and PET using 18F-FDG and 11C-methionine. As the tumor grew, we observed human-like symptoms in the mice, such as hemiplegia and hemiparesis. TIME characterization showed that this tumor model is mainly infiltrated by macrophages and almost devoid of lymphocytes. We are currently delving into the phenotype of these populations by scRNAseq and spatial transcriptomics. In addition, we are comparing our findings with human samples (n=15) to assess whether our model mimics human disease and can serve as a bonafide model of this tumor location. As a proof of concept, treatment of spinal DMG-bearing mice with a TIM-3 antagonist antibody, previously described as effective in pontine DMG-bearing mice, increased the median overall survival. We showed by microPET imaging that anti-TIM-3 administration into the brain ventricles diffuses to the tumor. These results open a path for the characterization of the spinal cord DMG TIME and for testing preclinical treatments in this new model.

EPCO-05. GENOMIC AND CLINICAL INSIGHTS FROM A LARGE-SCALE STUDY OF 172 RETINOBLASTOMAS

Abstract Retinoblastoma, a pediatric ocular cancer, is the only central nervous system tumor visible without specialized tools, readily detectable with the naked eye. This rare childhood cancer is mainly driven by mutations in RB1 or MYCN amplification, posing significant challenges in pediatric oncology. We conducted whole exome sequencing on 172 retinoblastoma tumors along with matched blood DNA from 171 patients, which included 119 unilateral, 49 bilateral, and three trilateral cases. Our analysis identified pathogenic variants in RB1 in 76 patients and MYCN duplication in 79 cases, highlighting their crucial roles in the disease. Additionally, we found mutations in RPTOR and TSC2, components of the mTOR signaling pathway, in two patients. Notably, our copy number alteration analysis revealed recurrent arm-level changes, including gains on 1q (23.3%), 2p (20.9%), and especially 6p (41.3%), along with other changes such as 5p gain (8.1%), 17q gain (8.1%), and 16q loss (5.8%). Our findings link these genetic alterations to specific clinical features; for instance, 6p gains were associated with Rubeosis, subretinal seeds, and tumor LC beyond, while 17q gains were linked to Rubeosis. Furthermore, gene collapsing techniques identified MATR3 and CYP4F2 as additional novel retinoblastoma-related genes, and module identification analysis pinpointed retinoblastoma-associated modules including HLA-DRB1-CBL, LPAR2, RB1, and TRIM28. Our study, the largest cohort of its kind, underscores the importance of next-generation sequencing from understudied populations in uncovering the complex genetic landscape of retinoblastoma, emphasizing the potential of precision medicine to enhance therapeutic strategies and improve outcomes for retinoblastoma patients.

GelMA microneedle-loaded bio-derived nanovaccine shows therapeutic potential for gliomas

ABSTRACT Glioma is the most common primary malignant tumor of the central nervous system in adults. Although immunotherapy, especially tumor vaccines, has made some progress in the treatment of gliomas compared with surgery and radiotherapy. However, the lack of specific or relevant tumor antigens severely limits the further development of tumor vaccines. Here, we report a bio-derived vaccine (TMV@CpG) derived from glioma cell membrane vesicles and carrying TLR9 agonist CpG as adjuvant, which was loaded onto the GelMA microneedle to obtain the microneedle vaccine (MN-TMV@CpG). Microneedle vaccine fully utilize the innate immune cells rich in the skin, inducing stronger cellular immune responses. In subcutaneous tumor models, MN-TMV@CpG reversed the immune-suppressing microenvironment of tumor, and effectively inhibited tumor progression. In an intracranial tumor model, MN-TMV@CpG significantly prolonged the survival duration and induced stronger immune memory responses in tumor bearing mice when combined with anti-PD1 mAb. These results suggest that bio-derived nanovaccines can be used as a potential antitumor immunotherapy strategy.

Study of Molecular Markers in Glioma and Their Association with Clinicopathological Features

Abstract Context: Central nervous system tumors are a major cause of morbidity and mortality worldwide. The most prevalent type of primary brain tumor is glioma. The exploration of significant genetic, epigenetic, and transcriptional abnormalities has not only improved our understanding of glioma pathogenesis but has also revealed that these molecular alterations can serve as useful diagnostic markers for more precise classification and are linked to better treatment response and prognosis. Hence, incorporating molecular markers into routine tumor classification is a major priority in modern glioma diagnostics. Aim: The aim is to assess the mutation status of isocitrate dehydrogenase (IDH)-1, alpha-thalassemia/mental retardation syndrome X-linked (ATRX), and tumor protein 53 in glioma, and look for their association with various clinicopathological features. Methodology: A single-center prospective cohort study, where all biopsies of glioma (January 2019 to July 2020) were evaluated, and immunohistochemistry was performed to assess the expression of IDH-1, ATRX, p53, and Ki-67 index. The data were analyzed using IBM SPSS-24 software. Results: Immunohistochemistry was performed in 123 consecutive cases of glioma. IDH-1 mutation was noted in 54 (43.9%) cases and these patients frequently presented with “seizures” (P = 0.006). The expression was maximum in World Health Organization (WHO) grade 2 tumors (65.4%) (P < 0.001), with the highest frequency in oligodendrogliomas (100% in WHO grade 2 and 3). Furthermore, these tumors showed lower proliferative indices (P = 0.001). ATRX mutation was noted in 59 (48%) and p53 overexpression was noted in 76 (61.8%) cases. These mutations were significantly associated with astrocytic phenotype (P = 0.03). Conclusions: Molecular characterization of glioma is an important step in modern glioma diagnostics and immunohistochemistry can play an important role. IDH-1 mutation is commonly observed in adults, frontal lobe location, patients presenting with seizures, and WHO grade 2 tumors with the highest frequencies in oligodendrogliomas. ATRX and p53 can be used as surrogate markers for tumors of astrocytic lineage.

Ependymal Tumors: Overview of the Recent World Health Organization Histopathologic and Genetic Updates with an Imaging Characteristic.

The 2021 World Health Organization Classification of Tumors of the Central Nervous System (CNS5), introduced significant changes, impacting tumors ranging from glial to ependymal neoplasms. Ependymal tumors were previously classified and graded based on histopathology, which had limited clinical and prognostic utility. The updated CNS5 classification now divides ependymomas into 10 subgroups based on anatomic location (supratentorial, posterior fossa, and spinal compartment) and genomic markers. Supratentorial tumors are defined by zinc finger translocation associated (ZFTA) (formerly v-rel avian reticuloendotheliosis viral oncogene [RELA]), or yes-associated protein 1 (YAP1) fusion; posterior fossa tumors are classified into groups A (PFA) and B (PFB), spinal ependymomas are defined by MYCN amplification. Subependymomas are present across all these anatomic compartments. The new classification kept an open category of "not elsewhere classified" or "not otherwise specified" if no pathogenic gene fusion is identified or if the molecular diagnosis is not feasible. Although there is significant overlap in the imaging findings of these tumors, a neuroradiologist needs to be familiar with updated CNS5 classification to understand tumor behavior, for example, the higher tendency for tumor recurrence along the dural flap for ZFTA fusion-positive ependymomas. On imaging, supratentorial ZFTA-fused ependymomas are preferentially located in the cerebral cortex, carrying predominant cystic components. YAP1-MAMLD1-fused ependymomas are intra- or periventricular with prominent multinodular solid components and have significantly better prognosis than ZFTA-fused counterparts. PFA ependymomas are aggressive paramedian masses with frequent calcification, seen in young children, originating from the lateral part of the fourth ventricular roof. PFB ependymomas are usually midline, noncalcified solid-cystic masses seen in adolescents and young adults arising from the fourth ventricular floor. PFA has a poorer prognosis, higher recurrence, and higher metastatic rate than PFB. Myxopapillary spinal ependymomas are now considered grade II due to high recurrence rates. Spinal-MYCN ependymomas are aggressive tumors with frequent leptomeningeal spread, relapse, and poor prognosis. Subependymomas are noninvasive, intraventricular, slow-growing benign tumors with an excellent prognosis. Currently, the molecular classification does not enhance the clinicopathologic understanding of subependymoma and myxopapillary categories. However, given the molecular advancements, this will likely change in the future. This review provides an updated molecular classification of ependymoma, discusses the individual imaging characteristics, and briefly outlines the latest targeted molecular therapies.

Complement C1S is a potential prognostic biomarker and associated with M2 macrophage infiltration in gliomas: From bioinformatics to comprehensive experimental validation

Glioma is the most common malignant tumor of the central nervous system, and the ability of traditional clinical treatment to prolong the survival of glioma patients is limited. A substantial body of evidence underscores the pivotal role of the immune system in eradicating malignant cells and impeding tumor metastasis. Consequently, tumor immunotherapy has become a promising avenue to address the clinical conundrum faced by glioma patients. The complement system is a natural immune system that is an important line of defense in the immune response. C1S plays a key role in activating the classical complement system. Nevertheless, few studies have focused on the role of C1S in glioma tumorigenesis and progression. In this study, we demonstrated that C1S was upregulated in GBM (Grade IV) and low-grade gliomas (LGG, Grade II-III) by combining glioma cohorts from multiple public databases with our internal independent cohorts and that increased C1S expression levels predict a poor prognosis for gliomas. Cox regression analysis identified C1S as an important prognostic indicator for glioma patients. In addition, gene functional enrichment analysis demonstrated that C1S was involved in cellular immunity, T-cell activation, macrophage differentiation, and cell proliferation. Further experiments demonstrated that C1S facilitates tumor cell proliferation, cell migration and intracranial tumor growth in nude mice. More importantly, we evaluated the role of C1S in immune infiltration. These results suggested that C1S was closely related to a variety of immune cell types in glioma, especially M2 macrophages. Our findings were further validated via glioma tissue microarray immunohistochemical analysis and an M2 macrophage infiltration assay. Together, these findings revealed the underlying critical role of C1S in glioma tumorigenesis, progression, and the tumor immune microenvironment, contributing to further understanding of glioma pathogenesis and guiding immunotherapy.

Consensus recommendations for an integrated diagnostic approach to peripheral nerve sheath tumors arising in the setting of Neurofibromatosis type 1 (NF1).

Consensus recommendation published in 2017 histologically defining atypical neurofibromatous neoplasm of uncertain biologic potential (ANNUBP) and malignant peripheral nerve sheath tumor (MPNST) were codified in the 2021 WHO Classification of Tumors of the Central Nervous System and the 2022 WHO Classification of Tumors of Soft Tissue and Bone. However, given the shift in diagnostic pathology toward the use of integrated histopathologic and genomic approaches, the incorporation of additional molecular strata in the classification of Neurofibromatosis Type 1 (NF1)-associated peripheral nerve sheath tumors should be formalized to aid in accurate diagnosis and early identification of malignant transformation to enable appropriate intervention for affected patients. To this end, we assembled a multi-institutional expert pathology working group as part of a "Symposium on Atypical Neurofibroma: State of the Science". Herein, we provide a suggested framework for adequate interventional radiology and surgical sampling, and recommend molecular profiling for clinically or radiologically worrisome non-cutaneous lesions in patients with NF1 to identify diagnostically-relevant molecular features, including CDKN2A/B inactivation for ANNUBP, as well as SUZ12, EED, or TP53 inactivating mutations, or significant aneuploidy for MPNST. We also propose renaming "low-grade MPNST" to "ANNUBP with increased proliferation" to avoid the use of the "malignant" term in this group of tumors with persistent unknown biologic potential. This refined integrated diagnostic approach for NF1-associated peripheral nerve sheath tumors should continue to evolve in concert with our understanding of these neoplasms.

Functional Roles of Long Non-coding RNAs on Stem Cell-related Pathways in Glioblastoma

: Long non-coding RNAs (lncRNAs), characterized by their length exceeding 200 nucleotides and lack of protein-coding capacity, are intricately associated with a wide array of cellular processes, encompassing cell invasion, differentiation, proliferation, migration, apoptosis, and regeneration. Perturbations in lncRNA expression have been observed in numerous diseases and have emerged as pivotal players in the pathogenesis of diverse tumor types. Glioblastoma, a highly malignant primary tumor of the central nervous system (CNS), remains a formidable challenge even with the advent of novel therapeutic interventions, as primary glioblastomas invariably exhibit therapy resistance and aggressive behavior. Glioblastomas can arise from progenitor cells or neuroglial stem cells, revealing profound cellular heterogeneity, notably in the form of glioblastoma stem cells (GSCs) possessing stem-like properties. Glioblastomas comprise neural precursors that harbor essential characteristics of neural stem cells (NSCs). Several signaling pathways have been implicated in the regulation of self-renewal in both cancer cells and stem cells. In addition to their involvement in therapy resistance and survival of glioblastoma, lncRNAs are implicated in the modulation of GSC behaviors through diverse pathways and the intricate regulation of various genes and proteins. This review aims to comprehensively discuss the interplay between lncRNAs, their associated pathways, and GSCs, shedding light on their potential implications in glioblastoma.

The engagement of Ras/Raf/MEK/ERK and PLCγ1/PKC pathways regulated by TrkB receptor in resistance of glioma cells to elimination upon apoptosis induction

The most aggressive tumors of human central nervous system are anaplastic astrocytoma (AA, III grade) and glioblastoma multiforme (GBM, IV grade) with an extremely bad prognosis. Their malignant character and resistance to standard therapy are correlated to the over-expression of survival pathways such as Ras/Raf/MEK/ERK and PLCγ1/PKC regulated by TrkB receptor. Therefore, the aim of this study was to investigate the engagement of those pathways in human glioma cells resistance for apoptosis induction by Temozolomide treatment. Two cancer MOGGCCM (AA) and T98G (GBM) and normal human astrocytes (NHA) cell lines were utilized. The tested inhibitors single and simultaneous action with Temozolomide affection on apoptosis induction was analyzed by MTT, microscopic observations and flow cytometry. Bcl-2:beclin-1 complexes occurrence was also assessed. siRNAs were used for direct proof of tested pathways engagement in gliomas resistance to apoptosis elimination. The most effective in eliminating gliomas with minimal astrocyte damage was 5 μM PLCγ1 inhibitor (U-73122) for MOGGCCM and 15 μM for T98G cells, and 1 μM LOXO-101 for all cancer cells. Sorafenib, Temozolomide, U-73122, and LOXO-101 effectively eliminate cancer cells. Single applications of sorafenib and Temozolomide were effective, but had lower efficiency than U-73122 and LOXO-101. These drugs induced apoptosis, affecting mitochondrial membrane potential and caspases 3, 8, and 9 activity. The study found that a Bcl-2:beclin-1 complex formation was observed when apoptosis was dominant. Inhibiting the pathways regulated by TrkB receptor combined with Temozolomide action, led to successful gliomas elimination. Those results might serve as basis for modern targeted treatment development.

Comparative analysis of stereotactic radiosurgery outcomes for supratentorial hemangioblastomas in von hippel-lindau disease and sporadic cases: A multi-center international study

BackgroundHemangioblastomas (HBs) are rare, benign central nervous system (CNS) neoplasms that rarely occur in the supratentorial. Resection with the goal of gross total resection (GTR) is often considered the primary treatment. Stereotactic radiosurgery (SRS) has been utilized more commonly in unresectable or partially resected cases. In this study, we aimed to evaluate SRS’s effectiveness and clinical outcomes in supratentorial HBs. MethodsA retrospective analysis of multi-centers from 1993 to 2022 was conducted on patients with supratentorial HB treated with SRS. ResultsThe study included 13 patients with 30 supratentorial HBs (24 von Hippel-Lindau (VHL), 6 sporadic). Median age was 26 years. Most tumors were solid (86.2 %). SRS was primary treatment in 86.7 % of cases and adjuvant in 13.3 %. VHL lesions were significantly smaller than sporadic ones (0.2 vs. 3.7 cc, p = 0.009). Median margin dose was higher in VHL cases (17 vs. 13.0 Gy, P = 0.031). For VHL cases, local control (LC) was 100 % at 6 months, 96 % (95 % CI: 88 %, 100 %) from 12 to 60 months post-SRS. For sporadic cases, LC was 100 % at 6 months, 80 % (95 % CI: 52 %, 100 %) from 12 to 60 months post-SRS (p = 0.39). No adverse radiation events or mortality occurred. ConclusionSRS demonstrated a promising role in the clinical course of supratentorial HBs. It can be considered an effective alternative to surgical resection and even a first-line therapeutic option in appropriately selected cases.

Large language models as a diagnostic support tool in neuropathology.

The WHO guidelines for classifying central nervous system (CNS) tumours are changing considerably with each release. The classification of CNS tumours is uniquely complex among most other solid tumours as it incorporates not just morphology, but also genetic and epigenetic features. Keeping current with these changes across medical fields can be challenging, even for clinical specialists. Large language models (LLMs) have demonstrated their ability to parse and process complex medical text, but their utility in neuro-oncology has not been systematically tested. We hypothesised that LLMs can effectively diagnose neuro-oncology cases from free-text histopathology reports according to the latest WHO guidelines. To test this hypothesis, we evaluated the performance of ChatGPT-4o, Claude-3.5-sonnet, and Llama3 across 30 challenging neuropathology cases, which each presented a complex mix of morphological and genetic information relevant to the diagnosis. Furthermore, we integrated these models with the latest WHO guidelines through Retrieval-Augmented Generation (RAG) and again assessed their diagnostic accuracy. Our data show that LLMs equipped with RAG, but not without RAG, can accurately diagnose the neuropathological tumour subtype in 90% of the tested cases. This study lays the groundwork for a new generation of computational tools that can assist neuropathologists in their daily reporting practice.

Rapid Intraoperative Amplicon Sequencing of CNS Tumor Markers

Currently, central nervous system tumors are diagnosed with an integrated diagnostic approach that combines histopathological examination with molecular genetic profiling, which requires days to weeks to achieve a precise and informative classification of CNS tumors. This study demonstrated the feasibility of rapid multiplexed amplicon nanopore sequencing for identifying critical mutations relevant to molecular stratification of brain tumors within the timeframe of standard resection surgery. Utilizing live analysis of nanopore sequencing data, we evaluated the brain tumor-associated molecular markers IDH1 R132, IDH2 R172, pTERT C228 and C250, H3F3A K27 and G34, Hist1H3B K27, and BRAF V600. Our method achieved a turnaround time of 105minutes at the point-of-care from receipt of a tumor biopsy to result with the potential to impact surgical strategy. Our approach can be integrated with recently developed DNA methylation-based diagnostic classification systems, corroborating diagnoses and even further specifying tumor grades, thus enabling a multimodal diagnostic intraoperative assessment of CNS malignancies.

Schwannomas of the upper limb: Clinical presentation, preoperative management and outcomes of surgical treatment

Inroduction: Schwannomas are the most common tumors of the peripheral nervous system. Surgical eradication with excision or enucleation is the treatment for symptomatic and large schwannomas. Aim: Few studies have investigated the clinical outcomes related to the surgical approach to schwannomas. Our study aims to evaluate the clinical and functional results of surgery for the treatment of upper limb schwannomas. Materials and methods: Twenty-two cases of upper limb schwannomas were surgically treated in our institution between January 2016 and December 2023. All cases underwent preoperative and 6-month postoperative MRI. For each case, we recorded the diagnostic interval (symptom-diagnosis), symptoms (stenosis or sensory deficits, pain, and Tinel test), and both pre-and postoperative functional status (with DASH and MSTS scores). We also recorded complications and local recurrences. Results: On average, the diagnosis was made 16.7 months after the onset of the first symptom. The mean preoperative MSTS, DASH, and MRC values were 27.9, 5.7, and 4.8, respectively. We had no intra-operative complications. After a mean follow-up of 43.1 months, MSTS, DASH were 29.7/30 and 0.7, respectively. No case developed local recurrences. No case recorded stenosis deficits at the last follow-up. Only one patient developed local paresthesia (9%), while two reported modest dysesthesias. Conclusions: An adequate surgical approach, possibly preceded by a rapid diagnosis, can significantly improve the symptoms caused by schwannoma, restoring the functionality of the upper limb.

Monocarboxylate transporter dependent mechanism is involved in proliferation, migration, and invasion of human glioblastoma cell lines via activation of PI3K/Akt signaling pathway.

Glioblastoma multiforme is one of the most common primary tumors of the central nervous system, with a very poor prognosis. Cancer cells have been observed to upregulate pH regulators, such as monocarboxylate transporters (MCTs), with an increase in MCT4 expression being observed in several malignancies. MCT4/ recombinant cluster of differentiation 147 (CD147) transporter complex was reported to stimulate vascular endothelial growth factor (VEGF) via the phosphatidylinositol 3 kinase (PI3K) /protein kinase B (Akt) pathway, which has been proven to mediate glioblastoma invasion and migration. The present study aimed to clarify the role of the MCT4/CD147 transporter complex in glioblastoma cell proliferation, migration, and invasion. In this work, lentiviral vectors were used to overexpress MCT4/CD147 and small interfering RNA (siRNA) was used to silence MCT4/CD147 in the human glioma cell lines U87 and U251, respectively. The effects on cell proliferation, migration and invasiveness, as well as the protein expression levels of MCT4 and CD147, extracellular lactate content and Akt activation were assessed by MTT, wound-healing and invasion assays, western blotting and colorimetric method, respectively. The analysis results suggested that cell proliferation, migration, invasion, and Akt activation were decreased by siRNA in all cell lines, but were increased by lentivirus-mediated MCT4 overexpression. These findings suggest that inhibiting the activity and expression of the MCT4/CD147 transporter complex via metabolic-targeting drugs, particularly in cells with a high rate of glycolysis, should be explored as a novel strategy for glioblastoma treatment.

Bibliometric and visualization analysis in the field of epigenetics and glioma (2009–2024)

IntroductionGlioma represents the most prevalent primary malignant tumor in the central nervous system, a deeper understanding of the underlying molecular mechanisms driving glioma is imperative for guiding future treatment strategies. Emerging evidence has implicated a close relationship between glioma development and epigenetic regulation. However, there remains a significant lack of comprehensive summaries in this domain. This study aims to analyze epigenetic publications pertaining to gliomas from 2009 to 2024 using bibliometric methods, consolidate the extant research, and delineate future prospects for investigation in this critical area.MethodsFor the purpose of this study, publications spanning the years 2009 to 2024 were extracted from the esteemed Web of Science Core Collection (WoSCC) database. Utilizing advanced visualization tools such as CiteSpace and VOSviewer, comprehensive data pertaining to various aspects including countries, authors, author co-citations, countries/regions, institutions, journals, cited literature, and keywords were systematically visualized and analyzed.ResultsA thorough analysis was conducted on a comprehensive dataset consisting of 858 publications, which unveiled a discernible trend of steady annual growth in research output within this specific field. The nations of the United States, China, and Germany emerged as the foremost contributors to this research domain. It is noteworthy that von Deimling A and the Helmholtz Association were distinguished as prominent authors and institutions, respectively, in this corpus of literature. A rigorous keyword search and subsequent co-occurrence analysis were executed, ultimately leading to the identification of seven distinct clusters: “epigenetic regulation”, “DNA repair”, “DNA methylation”, “brain tumors”, “diffuse midline glioma (DMG)”, “U-87 MG” and “epigenomics”. Furthermore, an intricate cluster analysis revealed that the primary foci of research within this field were centered around the exploration of glioma pathogenesis and the development of corresponding treatment strategies.ConclusionThis article underscores the prevailing trends and hotspots in glioma epigenetics, offering invaluable insights that can guide future research endeavors. The investigation of epigenetic mechanisms primarily centers on DNA modification, non-coding RNAs (ncRNAs), and histone modification. Furthermore, the pursuit of overcoming temozolomide (TMZ) resistance and the exploration of diverse emerging therapeutic strategies have emerged as pivotal avenues for future research within the field of glioma epigenetics.

A patient with heterochronous double primary tumor of basal ganglia germ cell tumors followed by diffuse hemispheric glioma: a case report.

Basal ganglia germ cell tumor (BGGCT) is a rare central nervous system (CNS) tumor. Diffuse hemispheric gliomas, H3 G34-mutant (DHGs) is an invasive glioma involving the cerebral hemispheres. The diagnosis of DHGs depends on the integration of histopathology and molecular pathology. We reported a patient with an initial diagnosis of BGGCT that was sensitive to subsequent chemoradiotherapy. Unfortunately, a second high-grade glioma was found on magnetic resonance imaging (MRI) six years later. Subsequently, the tumor was completely removed after surgery and the following histopathology plus next generation sequencing (NGS) testing confirmed the diagnosis of DHGs. Interestingly, we found a germline likely pathogenic variant in FANCA. After surgery, the patient received Stupp regimen. The patient had a relapse 13months after the Stupp regimen and was doing well after surgery. This is the first report of a patient with heterochronous double primary tumor of BGGCT followed by DHGs.