BACKGROUND: Glioblastoma (GBM) stands as the most prevalent and aggressive form of adult gliomas. Despite the implementation of intensive therapeutic approaches involving surgery, radiation, and chemotherapy, Glioblastoma Stem Cells contribute to tumor recurrence and poor prognosis. The induction of Glioblastoma Stem Cells differentiation by manipulating the transcriptional machinery has emerged as a promising strategy for GBM treatment. Here, we explored an innovative approach by investigating the role of the depolarized resting membrane potential (RMP) observed in patient-derived GBM sphereforming cell (GSCs), which allows them to maintain a stemness profile when they reside in the G0 phase of the cell cycle.
METHODS: We conducted molecular biology and electrophysiological experiments, both in vitro and in vivo, to examine the functional expression of the voltage-gated sodium channel (Nav) in GSCs, particularly focusing on its cell cycle-dependent functional expression. Nav activity was pharmacologically manipulated, and its effects on GSCs behavior were assessed by live imaging cell cycle analysis, self-renewal assays, and chemosensitivity assays. Mechanistic insights into the role of Nav in regulating GBM stemness were investigated through pathway analysis in vitro and through tumor proliferation assay in vivo.
RESULTS: We demonstrated that Nav is functionally expressed by GSCs mainly during the G0 phase of the cell cycle, suggesting its pivotal role in modulating the RMP. The pharmacological blockade of Nav made GBM cells more susceptible to temozolomide (TMZ), a standard drug for this type of tumor, by inducing cell cycle re-entry from G0 phase to G1/S transition. Additionally, inhibition of Nav substantially influenced the self-renewal and multipotency features of GSCs, concomitantly enhancing their degree of differentiation. Finally, our data suggested that Nav positively regulates GBM stemness by depolarizing the RMP and suppressing the ERK signaling pathway. Of note, in vivo proliferation assessment confirmed the increased susceptibility to TMZ following pharmacological blockade of Nav.
CONCLUSIONS: This insight positions Nav as a promising prognostic biomarker and therapeutic target for GBM patients, particularly in conjunction with temozolomide treatment.

BACKGROUND: Glioblastoma multiforme (GBM) is a highly aggressive primary malignant brain tumor characterized by rapid progression, poor prognosis, and high mortality rates. Understanding the relationship between cerebrospinal fluid (CSF) metabolites and GBM is crucial for identifying potential biomarkers and pathways involved in the pathogenesis of this devastating disease.
METHODS: In this study, Mendelian randomization (MR) analysis was employed to investigate the causal relationship between 338 CSF metabolites and GBM. The data for metabolites were obtained from a genome-wide association study summary dataset based on 291 individuals, and the GBM data was derived from FinnGen included 91 cases and 174,006 controls of European descent. The Inverse Variance Weighted method was utilized to estimate the causal effects. Supplementary comprehensive assessments of causal effects between CSF metabolites and GBM were conducted using MR-Egger regression, Weighted Median, Simple Mode, and Weighted Mode methods. Additionally, tests for heterogeneity and pleiotropy were performed.
RESULTS: Through MR analysis, a total of 12 identified metabolites and 2 with unknown chemical properties were found to have a causal relationship with GBM. 1-palmitoyl-2-stearoyl-gpc (16:0/18:0), 7-alpha-hydroxy-3-oxo-4-cholestenoate, Alpha-tocopherol, Behenoyl sphingomyelin (d18:1/22:0), Cysteinylglycine, Maleate, Uracil, Valine, X-12,101, X-12,104 and Butyrate (4:0) are associated with an increased risk of GBM. N1-methylinosine, Stachydrine and Succinylcarnitine (c4-dc) are associated with decreased GBM risk.
CONCLUSIONS: In conclusion, this study sheds light on the intricate interplay between CSF metabolites and GBM, offering novel perspectives on disease mechanisms and potential treatment avenues. By elucidating the role of CSF metabolites in GBM pathogenesis, this research contributes to the advancement of diagnostic capabilities and targeted therapeutic interventions for this aggressive brain tumor. Further exploration of these findings may lead to improved management strategies and better outcomes for patients with GBM.

BACKGROUND: Dendritic cell (DC) vaccines show promise for glioma treatment, but optimal use remains uncertain. This meta-analysis examined DC vaccine efficacy and safety for gliomas.
METHODS: This systematic review and meta-analysis study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. From the date of inception to October 23, 2023, electronic databases PubMed, Embase, Web of Science, and Scopus have been thoroughly evaluated.
RESULTS: A total of 12 studies with 998 patients and a mean age ranging from 40.2 to 56 years were included. Across 12 articles, DC vaccine 6-month overall survival (OS) was 100% [95% confidence interval {95%CI}: 100%-100%]. Respectively, 12-month OS reported 75% [95%CI: 65%-85%] but declined to 32% [95%CI: 20%-43%] for 24-month OS. 6- and 12-month progression-free survival reached 49% [95%CI: 21%-77%] and 19% [95%CI:8%-30%]. Studying radiological outcomes shows that complete response and partial response rates were 13% [95%CI: 17%-42%], and 26% [95%CI: 10%-42%], though stable disease reached 33% [95%CI: 15%-51%], suggesting predominant antineoplastic effects. The progressive disease rate also was 24% [95%CI: 9%-57%].
CONCLUSIONS: In gliomas, DC vaccinations show a temporary efficacy; stability is more prevalent than regression. Impacts favor decreased resistance to early disease. Enhancing efficacy remains critical. Early therapy can be enhanced by appropriate supplementary therapy integration.

UNASSIGNED: Glioblastoma (GBM) is a brain tumor with poor prognosis. Dexmedetomidine (Dex) regulates the biological behaviors of tumor cells to accelerate or decelerate cancer progression.
UNASSIGNED: We investigated the effects of Dex on the migration, invasion, and glycolysis in GBM.
UNASSIGNED: The concentration of Dex was determined using the cell counting kit-8 assay. The impacts of Dex on biological behaviors of GBM cells were assessed using Transwell assay, XF96 extracellular flux analysis, and western blot. The expression of c-Myc was examined using reverse transcription-quantitative polymerase chain reaction. The lactylation or stability of c-Myc was measured by western blot after immunoprecipitation or cycloheximide treatment.
UNASSIGNED: We found that Dex (200 nM) inhibited GBM cell viability, migration, invasion, and glycolysis. C-Myc was highly expressed in GBM cells and was decreased by Dex treatment. Moreover, Dex suppressed lactylated c-Myc levels via suppressing glycolysis, thereby reducing the protein stability of c-Myc. Sodium lactate treatment abrogated the effects of Dex on the biological behaviors of GBM cells.
UNASSIGNED: Dex suppressed the migration, invasion, and glycolysis of GBM cells via inhibiting lactylation of c-Myc and suppressing the c-Myc stability, suggesting that Dex may be a novel therapeutic drug for GBM treatment.

BACKGROUND: Glioblastoma (GBM) is a malignant astrocytic tumor and its progression involves the regulation of vascular endothelial growth factor-A (VEGFA). However, the mechanism of VEGFA in regulating GBM progression remains unclear.
METHODS: VEGFA mRNA expression was analyzed by quantitative real-time polymerase chain reaction. Protein expression of VEGFA, cluster of differentiation 9 (CD9), CD81, and transforming growth factor-β1 (TGF-β1) was detected by western blotting assay. Flow cytometry assay was conducted to assess cell proliferation, cell apoptosis and myeloid-derived suppressor cell (MDSC) differentiation. TUNEL cell apoptosis detection kit was utilized to analyze cell apoptosis of tumors. Angiogenic capacity was investigated by tube formation assay. Transwell assay was used to assess cell migration and invasion. The effect of VEGFA on tumor formation was determined by a xenograft mouse model assay. Immunohistochemistry assay was used to analyze positive expression rate of VEGFA in tumor tissues. TGF-β1 level was detected by enzyme-linked immunosorbent assay.
RESULTS: VEGFA expression was upregulated in GBM tissues, GBM cells, and exosomes from GBM patients and GBM cells. VEGFA silencing led to decreased cell proliferation, tube formation, migration and invasion and increased cell apoptosis. Moreover, VEGFA knockdown also delayed tumor formation. VEGFA promoted MDSC differentiation and TGF-β1 secretion by MDSCs by being packaged into exosomes. In addition, TGF-β1 knockdown displayed similar effects with VEGFA silencing on GBM cell phenotypes, and MDSCs attenuated VEGFA knockdown-induced effects by secreting TGF-β1 in A172 and U251 cells.
CONCLUSIONS: VEGFA contributed to tumor property of GBM cells by promoting MDSC differentiation and TGF-β1 secretion by MDSCs, providing potential targets for GBM treatment.

The cortical microenvironment surrounding malignant glioblastoma is a source of depolarizing crosstalk favoring hyperexcitability, tumor expansion, and immune evasion. Neosynaptogenesis, excess glutamate, and altered intrinsic membrane currents contribute to excitability dyshomeostasis, yet only half of the cases develop seizures, suggesting that tumor and host genomics, along with location, rather than mass effect, play a critical role. We analyzed the spatial contours and expression of 358 clinically validated human epilepsy genes in the human glioblastoma transcriptome compared to non-tumor adult and developing cortex datasets. Nearly half, including dosage-sensitive genes whose expression levels are securely linked to monogenic epilepsy, are strikingly enriched and aberrantly regulated at the leading edge, supporting a complex epistatic basis for peritumoral epileptogenesis. Surround hyperexcitability induced by complex patterns of proepileptic gene expression may explain the limited efficacy of narrowly targeted antiseizure medicines and the persistence of epilepsy following tumor resection and clarify why not all brain tumors provoke seizures.

Glioblastoma (GBM) is the most aggressive and lethal brain tumor. Artificial neural networks (ANNs) have the potential to make accurate predictions and improve decision making. The aim of this study was to create an ANN model to predict 15-month survival in GBM patients according to gene expression databases. Genomic data of GBM were downloaded from the CGGA, TCGA, MYO, and CPTAC. Logistic regression (LR) and ANN model were used. Age, gender, IDH wild-type/mutant and the 31 most important genes from our previous study, were determined as input factors for the established ANN model. 15-month survival time was used to evaluate the results. The normalized importance scores of each covariate were calculated using the selected ANN model. The area under a receiver operating characteristic (ROC) curve (AUC), Hosmer-Lemeshow (H-L) statistic and accuracy of prediction were measured to evaluate the two models. SPSS 26 was utilized. A total of 551 patients (61% male, mean age 55.5 ± 13.3 years) patients were divided into training, testing, and validation datasets of 441, 55 and 55 patients, respectively. The main candidate genes found were: FN1, ICAM1, MYD88, IL10, and CCL2 with the ANN model; and MMP9, MYD88, and CDK4 with LR model. The AUCs were 0.71 for the LR and 0.81 for the ANN analysis. Compared to the LR model, the ANN model showed better results: Accuracy rate, 83.3 %; H-L statistic, 6.5 %; and AUC, 0.81 % of patients. The findings show that ANNs can accurately predict the 15-month survival in GBM patients and contribute to precise medical treatment.

Not all patients with glioblastoma multiforme (GBM) eligible for systemic chemotherapy after upfront surgery and radiotherapy finally receive it. The information on patients with GBM was retrieved from the surveillance, epidemiology, and end results database. Patients who underwent upfront surgery or biopsy and external beam radiotherapy between 2010 and 2019 were eligible for systemic chemotherapy. The available patient and tumor characteristics were assessed using multivariable logistic regression and chi-squared test. Out of the 16,682 patients eligible, 92.1% underwent systemic chemotherapy. The characteristics linked to the lowest systemic chemotherapy utilization included tumors of the brain stem/cerebellum (P = 0.01), former years of diagnosis (P = 0.001), ≥ 80 years of age (P < 0.001), Hispanic, Non-Hispanic Asian, Pacific Islander, or Black race (P < 0.001), non-partnered status (P < 0.001), and low median household income (P = 0.006). Primary tumor site, year of diagnosis, age, race, partnered status, and median household income correlated with the omission of systemic chemotherapy in GBM in adult patients.

BACKGROUND: Anoikis is a specialized form of programmed cell death induced by the loss of cell adhesion to the extracellular matrix (ECM). Acquisition of anoikis resistance is a significant marker for cancer cell invasion, metastasis, therapy resistance, and recurrence. Although current research has identified multiple factors that regulate anoikis resistance, the pathological mechanisms of anoikis-mediated tumor microenvironment (TME) in glioblastoma (GBM) remain largely unexplored.
METHODS: Utilizing single-cell RNA sequencing (scRNA-seq) data and employing non-negative matrix factorization (NMF), we identified and characterized TME cell clusters with distinct anoikis-associated gene signatures. Prognostic and therapeutic response analyses were conducted using TCGA and CGGA datasets to assess the clinical significance of different TME cell clusters. The spatial relationship between BRMS1 + microglia and tumor cells was inferred from spatial transcriptome RNA sequencing (stRNA-seq) data. To simulate the tumor immune microenvironment, co-culture experiments were performed with microglia (HMC3) and GBM cells (U118/U251), and microglia were transfected with a BRMS1 overexpression lentivirus. Western blot or ELISA were used to detect BRMS1, M2 macrophage-specific markers, PI3K/AKT signaling proteins, and apoptosis-related proteins. The proliferation and apoptosis capabilities of tumor cells were evaluated using CCK-8, colony formation, and apoptosis assays, while the invasive and migratory abilities of tumor cells were assessed using Transwell assays.
RESULTS: NMF-based analysis successfully identified CD8 + T cell and microglia cell clusters with distinct gene signature characteristics. Trajectory analysis, cell communication, and gene regulatory network analyses collectively indicated that anoikis-mediated TME cell clusters can influence tumor cell development through various mechanisms. Notably, BRMS1 + AP-Mic exhibited an M2 macrophage phenotype and had significant cell communication with malignant cells. Moreover, high expression of BRMS1 + AP-Mic in TCGA and CGGA datasets was associated with poorer survival outcomes, indicating its detrimental impact on immunotherapy. Upregulation of BRMS1 in microglia may lead to M2 macrophage polarization, activate the PI3K/AKT signaling pathway through SPP1/CD44-mediated cell interactions, inhibit tumor cell apoptosis, and promote tumor proliferation and invasion.
CONCLUSIONS: This pioneering study used NMF-based analysis to reveal the important predictive value of anoikis-regulated TME in GBM for prognosis and immunotherapeutic response. BRMS1 + microglial cells provide a new perspective for a deeper understanding of the immunosuppressive microenvironment of GBM and could serve as a potential therapeutic target in the future.

Glioblastoma (GBM) is an aggressive brain cancer with limited therapeutic options. Natural killer (NK) cells are innate immune cells with strong anti-tumor activity and may offer a promising treatment strategy for GBM. We compared the anti-GBM activity of NK cells engineered to express interleukin (IL)-15 or IL-21. Using multiple in vivo models, IL-21 NK cells were superior to IL-15 NK cells both in terms of safety and long-term anti-tumor activity, with locoregionally administered IL-15 NK cells proving toxic and ineffective at tumor control. IL-21 NK cells displayed a unique chromatin accessibility signature, with CCAAT/enhancer-binding proteins (C/EBP), especially CEBPD, serving as key transcription factors regulating their enhanced function. Deletion of CEBPD resulted in loss of IL-21 NK cell potency while its overexpression increased NK cell long-term cytotoxicity and metabolic fitness. These results suggest that IL-21, through C/EBP transcription factors, drives epigenetic reprogramming of NK cells, enhancing their anti-tumor efficacy against GBM.