Glioblastoma and Other Primary Brain Malignancies in Adults: A Review

Role of the AKT signaling pathway in regulating tumor-associated macrophage polarization and in the tumor microenvironment: A review

Tumor-associated macrophages (TAMs) are present in and are important components of the tumor microenvironment (TME). TAMs differentiate into 2 functionally distinct morphologies, classically activated (M1)-type TAMs and alternatively activated (M2)-type TAMs, when stimulated by different cytokines. The 2 types of TAMs exhibit distinct properties and functions. M1 TAMs secrete high levels of pro-inflammatory and chemotactic factors, exerting proinflammatory, antitumor effects. Conversely, M2 TAMs alter the extracellular matrix, facilitate cellular immune escape, and stimulate tumor angiogenesis, thereby promoting anti-inflammatory responses and tumor growth. The ratio of M1 TAMs to M2 TAMs in the TME is closely related to the prognosis of the tumor. Tumor cells and other cells in the TME can regulate the polarization of TAMs and thus promote tumor progression through the secretion of various substances; however, polarized TAMs can also act on various cells in the TME through the secretion of exosomes, thus forming a positive feedback loop. Therefore, modulating the phenotype of TAMs in the TME or blocking the polarization of M2 TAMs might be a new approach for cancer treatment. However, the intracellular signaling pathways involved in the polarization of TAMs are poorly understood. The AKT signaling pathway is an important signaling pathway involved in the polarization, growth, proliferation, recruitment, and apoptosis of TAMs, as well as the action of TAMs on other cells within the TME. This paper reviews the AKT signaling pathway in the polarization of TAMs and the regulation of the TME and provides new ideas for tumor immunotherapy.

Intelligent molecular cleavage and dual-signal relay amplification ratiometric strategy for high-sensitivity analysis and dynamic monitoring of exosomal RNA in glioma

Exosomal RNA has emerged as a promising biomarker for glioblastoma (GBM) due to its exceptional stability in biofluids and strong correlation with tumor progression. In this study, we present an innovative intelligent molecular cleavage and dual-signal relay amplification-based ratiometric (ISR) strategy for high-sensitivity monitoring and dynamic analysis of exosomal RNA in glioma. The core mechanism is based on a hollow duplex structure that effectively prevents premature cleavage by duplex-specific nuclease (DSN), ensuring both the accuracy and stability of the detection system. Upon the introduction of the target microRNA (miRNA), one strand of the hollow duplex is displaced, forming a miRNA-DNA duplex that serves as a substrate for DSN, initiating target recycling and signal amplification. This dynamic process, coupled with dual-signal relay amplification, significantly enhances both sensitivity and stability, even at low miRNA concentrations. Our ratiometric approach substantially improves detection accuracy by comparing dual signal outputs. We further demonstrate the capability of real-time tracking of exosomal RNA dynamics, enabling precise monitoring of miRNA fluctuations over time. The practical applicability of our ISR strategy was validated by accurately detecting exosomal miRNA levels in clinical serum samples from glioblastoma patients, distinguishing them from healthy controls with high precision. Our method represents a significant advancement in early cancer detection and disease monitoring, with broad implications for precision medicine and the development of point-of-care diagnostic tools. Looking ahead, the ISR strategy holds great potential for monitoring a wide range of diseases, offering new opportunities for personalized diagnostics and therapeutic strategies.

Enhancing glioblastoma therapy: unveiling synergistic anticancer effects of Onalespib - radiotherapy combination therapy

Background

Glioblastoma (GBM) is the deadliest form of brain cancer, impacting both adults and children, marked by exceptionally high morbidity and mortality rates, even with current standard treatments such as surgery, radiation therapy, and chemotherapy. Therefore, there is a pressing need for new therapeutic strategies to improve survival and reduce treatment side effects. In this study, we investigated the effect of HSP90 inhibition in combination with radiotherapy in established and patient-derived glioblastoma cell lines.

Methods

Potential radiosensitizing effects of the HSP90 inhibitor Onalespib were studied in XTT and clonogenic survival assays as well as in tumor-mimicking multicellular spheroid models. Further, migration capacity and effects on protein expression were studied after exposure to Onalespib and radiation using Proximity Extension Assay analysis.

Results

HSP90 inhibition with Onalespib synergistically enhanced the radiosensitivity of glioblastoma cells grown in 2D and 3D models, resulting in increased cell death, reduced migration capacity and activation of the apoptotic signaling pathway. The proteomic analysis of glioblastoma cells treated with Onalespib, radiation, and their combination revealed significant alterations in protein expression profiles, involved in growth signaling, immune modulation pathways and angiogenesis. Moreover, the combination treatment indicated potential for enhancing cell cycle arrest and apoptosis, suggesting promising anti-tumor effects.

Conclusion

These findings demonstrate that HSP90 inhibition may be a promising strategy to enhance the efficacy of radiotherapy in the treatment of GBM, potentially leading to improved outcomes for patients battling this challenging disease.

Bioengineered NanoAid synergistically targets inflammatory pro-tumor processes to advance glioblastoma chemotherapy

Through transcriptomic analysis of patient-derived glioblastoma tissues, we identify an overactivation of inflammatory pathways that contribute to the development of a tumor-promoting microenvironment and therapeutic resistance. To address this critical mechanism, we present NanoAid, a biomimetic nanoplatform designed to target inflammatory pro-tumor processes to advance glioblastoma chemotherapy. NanoAid employs macrophage-membrane-liposome hybrids to optimize the delivery of COX-2 inhibitor parecoxib and paclitaxel. By inheriting macrophage characteristics, NanoAid not only efficiently traverses the blood-brain barrier and precisely accumulates within tumors but also enhances cancer cell uptake, thereby improving overall anticancer efficacy. Notably, the combination of parecoxib and paclitaxel effectively disrupts inflammatory pro-tumor processes while inducing a synergistic effect that inhibits tumor growth, overcomes therapeutic resistance, and minimizes adverse effects. This results in substantial tumor growth inhibition and extends the median survival of tumor-bearing mice. Thus, our study bridges clinical insights with fundamental research, potentially revolutionizing tumor therapy paradigms.

Political economics in health and implications for neurosurgery diseases

The field of political economics in health has a significant and far-reaching impact on public health. It encompasses a diverse range of interconnected domains, including the economy, welfare, the environment, food and drug safety, pollution emissions, occupational safety, the quality of medical services, consumer rights, public health policy, healthcare policy, scientific research, and marketing management. In this review, we examine the global influence of political economics on health outcomes and delineate the impact of prevalent neurosurgical conditions on individual and collective healthcare resources. This review will discuss the effects of political-economic factors on the prevalence and treatment of neurosurgical diseases, including stroke, traumatic brain injury (TBI), intracerebral hemorrhage (ICH), and brain malignant tumors. Furthermore, the current challenges and future directions will be discussed. We intend this review to facilitate the exchange and integration of political economics, public health, and neurosurgery, provide a foundation for policy development, enhance the prevention, diagnosis, and treatment of neurosurgical diseases, and ultimately promote public health.

Overexpression of miR-124 enhances the therapeutic benefit of TMZ treatment in the orthotopic GBM mice model by inhibition of DNA damage repair

Glioblastoma (GBM) is the most common malignant primary brain cancer with poor prognosis due to the resistant to current treatments, including the first-line drug temozolomide (TMZ). Accordingly, it is urgent to clarify the mechanism of chemotherapeutic resistance to improve the survival rate of patients. In the present study, by integrating comprehensive non-coding RNA-seq data from multiple cohorts of GBM patients, we identified that a series of miRNAs are frequently downregulated in GBM patients compared with the control samples. Among them, a high level of miR-124 is closely associated with a favorable survival rate in the clinical patients. In the phenotype experiment, we demonstrated that miR-124 overexpression increases responsiveness of GBM cells to TMZ-induced cell death, and vice versa. In the mechanistic study, we for the first time identified that RAD51, a key functional molecule in DNA damage repair, is a novel and bona fide target of miR-124 in GBM cells. Given that other miR-124-regulated mechanisms on TMZ sensitivity have been reported, we performed recue experiment to demonstrate that RAD51 is essential for miR-124-mediated sensitivity to TMZ in GBM cells. More importantly, our in vivo functional experiment showed that combinational utilization of miR-124 overexpression and TMZ presents a synergetic therapeutic benefit in the orthotopic GBM mice model. Taken together, we rationally explained a novel and important mechanism of the miR-124-mediated high sensitivity to TMZ-induced cell death in GBM and provided evidence to support that miR-124-RAD51 regulatory axis could be a promising candidate in the comprehensive treatment with TMZ in GBM.

Optimizing Therapeutics for Intratumoral Cancer Treatments: Antiproliferative Vanadium Complexes in Glioblastoma

Glioblastoma, an aggressive cancer, is difficult to treat due to its location, late detection, drug resistance, and poor absorption of chemotherapeutics. Intratumoral drug administration offers a promising potential treatment alternative with localized delivery and minimal systemic toxicity. Vanadium(V) coordination complexes, incorporating Schiff base and catecholate ligands, have shown effects as antiproliferative agents with tunable efficacy and reactivity, stability, steric bulk, hydrophobicity, uptake, and toxicity optimized for the intratumoral administration vehicle. A new series of oxovanadium(V) Schiff base-catecholate complexes were synthesized and characterized using nuclear magnetic resonance (NMR), UV-Vis, and infrared spectroscopy and mass spectrometry. Stability under physiological conditions was assessed via UV-Vis spectroscopy, and the antiproliferative activity was evaluated in T98G glioblastoma and SVG p12 normal glial cells using viability assays. The newly synthesized [VO(3-tBuHSHED)(TIPCAT)] complex was more stable (t1/2 ~4.5 h) and had strong antiproliferative activity (IC50 ~1.5 µM), comparing favorably with the current lead compound, [VO(HSHED)(DTB)]. The structural modifications enhanced stability, hydrophobicity, and steric bulk through substitution with iso-propyl and tert-butyl groups. The improved properties were attributed to steric hindrance associated with the new Schiff base and catecholato ligands, as well as the formation of non-toxic byproducts upon degradation. The [VO(3-tBuHSHED)(TIPCAT)] complex emerges as a promising candidate for glioblastoma therapy by demonstrating enhanced stability and a greater selectivity, which highlights the role of strategic ligand design in developing localized therapies for the treatment of resistant cancers. In reporting the new class of compounds effective against T98G glioblastoma cells, we describe the generally desirable properties that potential drugs being developed for intratumoral administration should have.

FTO Suppresses Proliferation and Induces Apoptosis of T98G Glioblastoma Cells via N6-methyladenosine Modification of GSTO1

Glioblastoma (GBM) is the most malignant type of glioma with a very poor prognosis. N6-methyladenosine (m6A) is well-documented to be involved in GBM progression, and FTO is a demethylase. GSTO1 is also associated with tumor progression. This study aimed to investigate the impact of FTO and GSTO1 on GBM progression and the regulation of FTO on m6A modification of GSTO1. T98G cell phenotypes including proliferation and apoptosis were analyzed by cell counting kit 8, colony formation assay, and flow cytometry. The regulation of m6A methylation mediated by FTO was evaluated by methylated RNA immunoprecipitation, RNA immunoprecipitation, and dual-luciferase reporter assay. The results showed that FTO expression was downregulated in GBM. Overexpression of FTO inhibited cell proliferation and facilitated apoptosis in vitro. Additionally, GSTO1 expression was elevated in GBM, and knockdown of GSTO1 suppressed cell proliferation and promoted apoptosis and oxidative stress. Moreover, FTO inhibited m6A methylation of GSTO1 and reduced the stability of GSTO1. Overexpression of GSTO1 abrogated T98G cellular processes mediated by FTO. The in vivo experiments showed that FTO inhibited tumor growth by downregulating GSTO1 expression. In conclusion, FTO decelerates GBM progression by inducing apoptosis through suppressing m6A methylation of GSTO1.

68Ga-NOTA-RM26 PET/CT in the evaluation of glioma: a pilot prospective study

BACKGROUND

Gliomas are the most common malignant primary tumors of the central nervous system. There is an urgent need for new convenient, targeted and specific imaging agents for gliomas. This study aimed to firstly evaluate the feasibility of 68Ga-NOTA-RM26 PET/CT imaging in glioma and analyze the relationship between the imaging characteristics and glioma grade, classification and molecular alterations.

RESULTS

Twenty-two patients were confirmed as glioma by surgery or biopsy. All patients exhibited 68Ga-NOTA-RM26 uptake. SUVmax was chosen as the imaging marker for analysis. For all glioma patients, there were significant differences between grades (P = 0.047). For primary gliomas, SUVmax had good discrimination for both tumor classifications (P = 0.045) and grades (P = 0.03). There was a positive correlation (P < 0.01) between GRPR expression level and SUVmax. P53 mutations caused significant differences in SUVmax (P = 0.03).

CONCLUSIONS

This study is the first application of 68Ga-NOTA-RM26 in glioma patients and confirmed the safety and efficacy in glioma patients. 68Ga-NOTA-RM26 PET/CT has potential value in tumor grade, classification, and molecular alterations.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT06412952. Registered 26 April 2024, https://clinicaltrials.gov/study/NCT06412952.

Implication of tumor morphology and MRI characteristics on the accuracy of automated versus human segmentation of GBM areas

An assessment scheme is proposed to evaluate GBM gross tumor core and T2-FLAIR hyper-intensity segmentations on preoperative multicentric MR images as a function of tumor morphology and MRI characteristics. 74 gross tumor core and T2-FLAIR hyper-intensity BraTS-Toolkit and DeepBraTumIA automatic segmentations, and 42 gross tumor core neurosurgeon manual segmentations were accordingly evaluated. Brats-Toolkit and DeepBraTumIA generally provide accurate segmentations, particularly for the most common round-shaped or well-demarked tumors, where: (1) gross tumor segmentation correctly includes necrosis and contrast enhanced tumor in 100% and 97.06% of cases (vs. 73.68% for manual segmentation) and wrongly includes healthy or non-tumor related tissues in 2.94% and 20.59% of cases (vs. 10.53% for manual segmentations); (2) T2-FLAIR hyper-intensity segmentations completely includes edema in 88.24% of cases for both software. MR image quality has little impact on the segmentation performance on these tumors. Conversely, on less common tumors with more complex tissue distribution and infiltrative behavior, manual segmentation works better than BraTS-Toolkit and DeepBraTumIA, and image quality has a larger impact on automatic segmentation performance. BraTS-Toolkit and DeepBraTumIA gross tumor segmentation properly includes necrosis and contrast enhanced areas in 50% and 37.50% of cases (vs. 66.67% for manual segmentation), all corresponding to higher image quality; T2-FLAIR hyper-intensity segmentation wrongly includes necrosis and contrast enhanced areas in 37.50% and 50% of cases.

Long Non-Coding RNAs in Malignant Human Brain Tumors: Driving Forces Behind Progression and Therapy

Long non-coding RNAs (lncRNAs) play a pivotal role in regulating gene expression and are critically involved in the progression of malignant brain tumors, including glioblastoma, medulloblastoma, and meningioma. These lncRNAs interact with microRNAs (miRNAs), proteins, and DNA, influencing key processes such as cell proliferation, migration, and invasion. This review highlights the multifaceted impact of lncRNA dysregulation on tumor progression and underscores their potential as therapeutic targets to enhance the efficacy of chemotherapy, radiotherapy, and immunotherapy. The insights provided offer new directions for advancing basic research and clinical applications in malignant brain tumors.

The HOX Gene Family's Role as Prognostic and Diagnostic Biomarkers in Hematological and Solid Tumors

The HOX gene family encodes for regulatory transcription factors that play a crucial role in embryogenesis and differentiation of adult cells. This highly conserved family of genes consists of thirty-nine genes in humans that are located in four clusters, A-D, on different chromosomes. While early studies on the HOX gene family have been focused on embryonic development and its related disorders, research has shifted to examine aberrant expression of HOX genes and the subsequent implication in cancer prediction and progression. Due to their role of encoding master regulatory transcription factors, the abnormal expression of HOX genes has been shown to affect all stages of tumorigenesis and metastasis. This review highlights the novel role of the HOX family's clinical relevance as both prognostic and diagnostic biomarkers in hematological and solid tumors.

Relationship between CTF1 gene expression and prognosis and tumor immune microenvironment in glioma

OBJECTIVE

This study aimed to evaluate CTF1 expression in glioma, its relationship to patient prognosis and the tumor immune microenvironment, and effects on glioma phenotypes to identify a new therapeutic target for treating glioma precisely.

METHODS

We initially assessed the expression of CTF1, a member of the IL-6 family, in glioma, using bioinformatics tools and publicly available databases. Furthermore, we examined the correlation between CTF1 expression and tumor prognosis, DNA methylation patterns, m6A-related genes, potential biological functions, the immune microenvironment, and genes associated with immune checkpoints. We also explored potential associations with drug sensitivity. To assess the impact on glioma cell proliferation and apoptosis, we employed various assays, including the Cell Counting Kit-8, colony formation assay, and flow cytometry.

RESULTS

CTF1 gene and protein expression were significantly elevated in glioma tissues, and correlated with malignancy and poor prognosis. CTF1 was an independent prognostic factor and negatively associated with DNA methylation. The involvement of CTF1 in m6A modifications contributed to glioma progression. Enrichment analysis revealed immune response pathways linked with CTF1 in glioma, including natural killer cell cytotoxicity, NOD-like receptor signaling, Toll-like receptor signaling, antigen processing, chemokine signaling, and cytokine receptor interactions. CTF1 expression correlated positively with pathways related to apoptosis, inflammation, proliferation, and epithelial-mesenchymal transition, and PI3K-AKT-mTOR signaling. Additionally, CTF1 expression was positively associated with macrophage, eosinophil, and neutrophil contents and immune checkpoint-related genes, but negatively associated with sensitivity to 14 drugs. In vitro experiments confirmed that CTF1 knockdown inhibited glioma cell proliferation and promoted apoptosis.

CONCLUSION

This study identifies CTF1 as a significant independent prognostic factor that is closely associated with the tumor immune microenvironment in glioma. Additionally, reduced expression of CTF1 suppresses the proliferation and induces apoptosis of glioma cells in vitro. Consequently, CTF1 is a potentially promising novel therapeutic target for glioma treatment.

Comprehensive Analysis Identifies THEMIS2 as a Potential Prognostic and Immunological Biomarker in Glioblastoma

Glioblastoma (GBM) is a highly aggressive brain tumor characterized by its ability to evade the immune system, hindering the efficacy of current immunotherapies. Recent research has highlighted the important role of immunosuppressive macrophages in the tumor microenvironment (TME) in driving this immune evasion. In this study, we are the first to identify THEMIS2 as a key regulator of tumor-associated macrophage (TAM)-mediated immunosuppression in GBM. We found that a high THEMIS2 expression is associated with poor patient outcomes and increased infiltration of immune cells, particularly macrophages. Functional analyses revealed THEMIS2's critical involvement in immune-related pathways, including immune response activation, mononuclear cell differentiation, and the positive regulation of cytokine production. Additionally, single-cell RNA sequencing data demonstrated that macrophages with a high THEMIS2 expression were associated with increased phagocytosis, immune suppression, and enhanced tumor growth. These findings suggest that THEMIS2 could serve as both a prognostic marker and a therapeutic target for enhancing anti-tumor immunity in GBM.

Spatial Transcriptomics: Biotechnologies, Computational Tools, and Neuroscience Applications

Spatial transcriptomics (ST) represents a revolutionary approach in molecular biology, providing unprecedented insights into the spatial organization of gene expression within tissues. This review aims to elucidate advancements in ST technologies, their computational tools, and their pivotal applications in neuroscience. It is begun with a historical overview, tracing the evolution from early image-based techniques to contemporary sequence-based methods. Subsequently, the computational methods essential for ST data analysis, including preprocessing, cell type annotation, spatial clustering, detection of spatially variable genes, cell-cell interaction analysis, and 3D multi-slices integration are discussed. The central focus of this review is the application of ST in neuroscience, where it has significantly contributed to understanding the brain's complexity. Through ST, researchers advance brain atlas projects, gain insights into brain development, and explore neuroimmune dysfunctions, particularly in brain tumors. Additionally, ST enhances understanding of neuronal vulnerability in neurodegenerative diseases like Alzheimer's and neuropsychiatric disorders such as schizophrenia. In conclusion, while ST has already profoundly impacted neuroscience, challenges remain issues such as enhancing sequencing technologies and developing robust computational tools. This review underscores the transformative potential of ST in neuroscience, paving the way for new therapeutic insights and advancements in brain research.

Glioblastoma: Clinical Presentation, Multidisciplinary Management, and Long-Term Outcomes

Glioblastoma, the most common and aggressive primary brain tumor in adults, presents a formidable challenge due to its rapid progression, treatment resistance, and poor survival outcomes. Standard care typically involves maximal safe surgical resection, followed by fractionated external beam radiation therapy and concurrent temozolomide chemotherapy. Despite these interventions, median survival remains approximately 12-15 months, with a five-year survival rate below 10%. Prognosis is influenced by factors such as patient age, molecular characteristics, and the extent of resection. Patients with IDH-mutant tumors or methylated MGMT promoters generally have improved survival, while recurrent glioblastoma is associated with a median survival of only six months, as therapies in these cases are often palliative. Innovative treatments, including TTFields, add incremental survival benefits, extending median survival to around 20.9 months for eligible patients. Symptom management-addressing seizures, headaches, and neurological deficits-alongside psychological support for patients and caregivers is essential to enhance quality of life. Emerging targeted therapies and immunotherapies, though still limited in efficacy, show promise as part of an evolving treatment landscape. Continued research and clinical trials remain crucial to developing more effective treatments. This multidisciplinary approach, incorporating diagnostics, personalized therapy, and supportive care, aims to improve outcomes and provides a hopeful foundation for advancing glioblastoma management.

RBM47 is a novel immunotherapeutic target and prognostic biomarker in gliomas

The role of RBM47, an RNA-binding protein, in shaping the immune landscape of gliomas and tumor immune responses is yet to be fully studied. Therefore, a comprehensive investigation into the immunomodulatory roles of RBM47 in gliomas was conducted, leveraging gene expression data from multi-omic datasets. The prognosis of patients with gliomas considering RBM47 was elucidated using bioinformatics methods and clinical data, with results validated using immunohistochemistry and immunofluorescence analyses. The expression of RBM47 in gliomas was higher than that in normal tissues and was positively correlated with the World Health Organization tumor grade. Increased RBM47 expression is associated with poor prognosis in patients with glioma, serving as an independent predictor of overall survival. The nomogram combining RBM47 expression levels with clinical prognostic factors demonstrated strong predictive accuracy, achieving a C-index of up to 0.863 in both TCGA training and CGGA validation groups. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Gene Set Variation Analysis indicated that RBM47 is closely related to immunity and inflammation. Single-cell sequencing and immunofluorescence assays confirmed the enrichment of RBM47 in CD163 + macrophages. Therefore, RBM47 plays a vital role in the immune microenvironment of gliomas and may be a potential immunotherapy target.

Clofazimine enhances anti-glioma effect of immunotherapy

RATIONALE

Glioblastoma is one of the most aggressive human brain tumors. The prognosis is unfavorable and treatment effects are relatively low. However, temozolomide (TMZ) chemotherapy may prolong patients' survival.

OBJECTIVE OF THE PAPER

The anti-glioma effect of clofazimine used in immunotherapy is examined in vivo.

MATERIALS AND METHODS

Method of obtaining TMZ-resistant GB cells included treatment of T98G glioblastoma cells with 150 μmol/l TMZ. To confirm resistance to TMZ, MTT assay was performed according to the manufacturer's protocol. Untreated cells were used as a control group. C6 glioma cells were stereotactically implanted into the brain of Wistar rats and irradiated (24 Gy) in combination with oral administration of TMZ (20 mg/ kg) and clofazimine (CFZ) (30 mg/kg). This was followed by subsequent immunotherapy including tumor cell and dendritic cell vaccines. Neurovisualisation, immunocytochemical and immunohistochemical assays were used and animals' survival was analyzed with Kaplan-Meier estimator.

RESULTS

T98G resistant glioblastoma cell line is characterized by immunoreactive β-catenin, CD133, CD44, and N-cadherin as compared to the control cell line. The IC 50 of clofazimine for T98G glioblastoma cell line is 38.3 ± 4,1 μmol/l, for C6 rat glioma cell line is 37,6 ± 3,2 μmol/l. Clofazimine enhanced the cytotoxic activity of temozolomide, paclitaxel, and carboplatin in cancer cells of T98G line as compared to the control group. The cytotoxic effect of lomustine and carboplatin against T98G resistant glioblastoma cells was also enhanced by Clofazimine. Tumor cell vaccine (TCV) and dendritic cell vaccine (DCV) in combination with clofazimine produces a stronger anti-tumor immune response in C6 glioma. This is evident with development of local inflammatory reaction with higher content of interleukin 1β and 18 in serum, as well as greater level of IBA1+, CD68 + in pro-inflammatory microglia of neoplastic tissues. Combined use of DCV and clofazimine results in higher survival rates in experimental animals (- 90 ± 7 days against 45 ± 5 days) in the treated group with chemoradiation therapy (CRT).

CONCLUSIONS

Combination of clofazimine and immunotherapy enhances anti-glioma effect of TMZ in an in vivo model experiment.

Unsupervised clustering reveals noncanonical myeloid cell subsets in the brain tumor microenvironment

The tumor immune microenvironment (TiME) of human central nervous system (CNS) tumors remains to be comprehensively deciphered. Here, we employed flow cytometry and RNA sequencing analysis for a deep data-driven dissection of a diverse TiME and to uncover noncanonical immune cell types in human CNS tumors by using seven tumors from five patients. Myeloid subsets comprised classical microglia, monocyte-derived macrophages, neutrophils, and two noncanonical myeloid subsets: CD3+ myeloids and CD19+ myeloids. T lymphocyte subsets included double-negative (CD4- CD8-) T cells (DNTs). Noncanonical myeloids and DNTs were explored on independent datasets, suggesting that our DNT phenotype represents γδ T cells. Noncanonical myeloids were validated using orthogonal methods across 73 patients from three independent datasets. While the proportions of classical myeloids agreed with reported malignancy type-associated TiMEs, unexpectedly high lymphocyte frequencies were detected in gliosarcoma, which also showed a unique expression pattern of immune-related genes. Our findings highlight the potential of data-driven approaches in resolving CNS TiME to reveal the mosaic of immune cell types constituting TiME, warranting the need for future studies on the nonclassical immune cell subsets.

Survival and immune microenvironment prediction of glioma based on MRI imaging genomics method: a retrospective observational study

Glioma is characterized by high heterogeneity and poor prognosis. Attempts have been made to understand its diversity in both genetic expressions and radiomic characteristics, while few integrated the two omics in predicting survival of glioma. This study was intended to investigate the connection between glioma imaging and genome, and examine its predictive value in glioma mortality risk and tumor immune microenvironment (TIME). Clinical, transcriptomics and radiomics data were obtained from public datasets and patients in our center. Correlation analysis between gene expression and radiomic feature (RF) was performed, followed by survival analysis to select RF-related genes (RFRGs) and gene expression-related RFs (GRRFs). After that, RFRGs and GRRFs were used to construct mortality risk prediction model of all glioma and isocitrate dehydrogenase (IDH) wild type (WT) glioma. The association between RFRGs and TIME was explored. Six cohorts composed of 1,754 glioma patients were included. Thirty-five genes and eighty-two RFs demonstrated high correlation with each other. Gene score based on RFRGs was independent predictor of both glioma (P < 0.05) and IDH-WT glioma (P < 0.05). Same score based on GRRFs was also able to stratify risk of both glioma (P < 0.0001) and IDH-WT glioma (P < 0.0001), with nomograms constructed separately. The TIME of gliomas predicted with RFRGs' score found mismatched risk of death with immune response. RFRGs and GRRFs were able to predict glioma mortality risk and TIME. Further studies could validate our results and explore this genome-imaging interactions.

Agathisflavone Inhibits Viability and Modulates the Expression of miR-125b, miR-155, IL-6, and Arginase in Glioblastoma Cells and Microglia/Macrophage Activation

Glioblastomas (GBM) are malignant tumours with poor prognosis. Treatment involves chemotherapy and/or radiotherapy; however, there is currently no standard treatment for recurrence, and prognosis remains unfavourable. Inflammatory mediators and microRNAs (miRNAs) influence the aggressiveness of GBM, being involved in the communication with the cells of the tumour parenchyma, including microglia/macrophages, and maintaining an immunosuppressive microenvironment. Hence, the modulation of miRNAs and inflammatory factors may improve GBM treatments. In this study, we investigated the effects of agathisflavone, a biflavonoid purified from Cenostigma pyramidale (Tul.), on the growth and migration of GBM cells, on the expression of inflammatory cytokines and microRNAs, as well on the response of microglia. Agathisflavone (5-30 μM) induced a dose- and time-dependent reduction in the viability of both human GL-15 and rat C6 cells, as determined by the MTT test, and reduced cell migration, as determined by cell scratch assay. RT-qPCR analysis revealed that agathisflavone (5 μM) down-regulated the expression of miR-125b and miR-155 in the secretome derived from GL-15 cells, which was associated with upregulation of the mRNA expression of IL-6 and arginase-1 immunoregulatory factors. Exposure of human microglia/macrophage to the secretome from GL-15 GMB cells modulated proliferation and morphology, effects that were modulated by agathisflavone treatment. These results demonstrate the effect of flavonoids on the growth of GBM cells, which impacts cells in the microenvironment and can be considered for preclinical studies for adjuvant treatments.

IGF2BP2 orchestrates global expression and alternative splicing profiles associated with glioblastoma development in U251 cells

Glioblastoma (GBM) is a highly invasive and malignant central nervous system tumor with a median survival duration of 15 months despite multimodal therapy. The insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) has been implicated in various cancers and is known to regulate RNA metabolism and alternative splicing (AS). However, its role in GBM remains unclear. Overexpression of IGF2BP2 led to significant alterations in gene expression, with 472 genes upregulated and 99 downregulated. Gene ontology (GO) analysis indicated enrichment in immune-related biological processes. Notably, IGF2BP2 was found to regulate AS events, with 1372 regulated AS genes (RASGs) and 2096 significantly distinct ASEs identified. Furthermore, IGF2BP2 selectively bound to 3' and 5' untranslated regions (UTRs) via GG[AU]C motifs, and IFIH1 was identified as a direct binding partner and upregulated gene upon IGF2BP2 overexpression. Functional enrichment analysis suggested that IGF2BP2 influences pathways related to RNA splicing and immune responses. Our findings demonstrate that IGF2BP2 plays a crucial role in GBM by modulating the transcriptome and AS events. The upregulation of immune-related genes and the regulation of AS by IGF2BP2 highlight its potential as a therapeutic target in GBM, particularly for immunotherapy. The study provides a foundation for further investigation into the molecular mechanisms of IGF2BP2 in GBM and its implications for cancer treatment.

Novel Treatments for Brain Tumors

The blood-brain barrier and knowledge gaps in tumor biology remain significant obstacles to the development of effective treatments for brain tumors. The identification of shared molecular and genetic pathways that contribute to tumorigenesis in both dogs and people has been key to the discovery and translation of targeted pharmacologic and biologic therapies. Treatment approaches often utilize targeted or multifunctional antitumor agents, such as nanocarriers, molecularly targeted agents, immunotherapeutics, and oncolytic viruses in combination with alternative therapeutic delivery strategies. The article discusses about various treatments albeit none of the treatments discussed here are widely available or approved for clinical use.

Quantification of the Engraftment Status of Mesenchymal Stem Cells in Glioma Using Dual-Modality Magnetic Resonance Imaging and Bioluminescence Imaging

RATIONALE AND OBJECTIVES

The tumor-tropic properties of mesenchymal stem cells (MSCs) enable them to serve as appealing cellular vehicles for delivering therapeutic agents to treat malignant glioma. However, the exact engraftment status of MSCs in glioma via different administration routes remains unclear due to the lack of quantitative analysis. This study aimed to quantify the engraftment of MSCs in glioma after administration via different routes using non-invasive dual-modality magnetic resonance imaging (MRI) and bioluminescence imaging (BLI).

MATERIALS AND METHODS

MSCs were transduced with a lentivirus overexpressing ferritin heavy chain (FTH) and firefly luciferase (FLUC) reporter genes to yield FTH- and FLUC-overexpressed MSCs (FTH-FLUC-MSCs). Wistar rats bearing intracranial C6 glioma received peritumoral, intratumoral, intra-arterial, and intravenous injection of FTH-FLUC-MSCs, respectively. MRI and BLI were performed to monitor FTH-FLUC-MSCs in vivo.

RESULTS

FTH-FLUC-MSCs administered via peritumoral, intratumoral and intra-arterial routes migrated specially toward the intracranial glioma in vivo, as detected by MRI and BLI. As quantified by the BLI signal intensity, the percentages of FTH-FLUC-MSCs in the glioma were significantly higher with peritumoral injection (61%) and intratumoral injection (71%) compared to intra-arterial injection (30%) and intravenous injection (0%). Peritumorally injected FTH-FLUC-MSCs showed a gradual decline, with approximately 6% of FTH-FLUC-MSCs still retained within the tumor up to 11 days after injection. Meanwhile, the number of FTH-FLUC-MSCs injected via other routes dropped quickly, and none were detectable by day 11 post-injection.

CONCLUSION

Peritumoral delivery of FTH-FLUC-MSCs offers robust engraftment and could be used as the optimal delivery route for treating malignant glioma.

Plinabulin exerts an anti-proliferative effect via the PI3K/AKT/mTOR signaling pathways in glioblastoma

Objectives

Plinabulin, a marine-derived anticancer drug targeting microtubules, exhibits anti-cancer effects on glioblastoma cells. However, its therapeutic potential, specifically for glioblastoma treatment, remains underexplored. This study aims to elucidate the mechanisms by which plinabulin exerts its effects on glioblastoma cells.

Materials and Methods

Using the SRB and colony formation assay to observe the effect of plinabulin on glioblastoma cell viability. Wound healing and transwell migration assay were used to test the effect of plinabulin on glioblastoma cell metastatic potential. Crucial target genes were identified through RNA sequencing and bioinformatics analysis. Protein levels were evaluated in a concentration-dependent manner using western blot analysis.

Results

Plinabulin suppressed glioblastoma cell proliferation by causing cell cycle G2/M phase arrest and inhibited migration. The IC50 values were 22.20 nM in A172 cells and 20.55 nM in T98G cells. Plinabulin reduced AKT and mTOR phosphorylation. Combined with the AKT/mTOR inhibitors LY294002 and rapamycin, plinabulin decreased p-mTOR and EGFR protein levels and increased cleaved-PARP levels. Plinabulin induces autophagy, and using an autophagy inhibitor enhances plinabulin-induced cell apoptosis. This suggests that plinabulin might trigger cytoprotective autophagy in glioblastoma cells. These findings indicate that plinabulin hinders glioblastoma growth and induces protective autophagy via the PI3K/AKT/mTOR pathway. Additionally, plinabulin combined with erlotinib showed greater cytotoxic efficacy than either drug alone in glioblastoma cells in vitro.

Conclusion

Our study provides new insights into the efficacy of plinabulin against glioblastoma and highlights the potential clinical utility of combining plinabulin with EGFR inhibitors as a chemotherapy strategy.

Metabolically-Driven Active Targeting of Magnetic Nanoparticles Functionalized with Glucuronic Acid to Glioblastoma: Application to MRI-Tracked Magnetic Hyperthermia Therapy

Glioblastoma continues to pose a major global health challenge due to its incurable nature. The need for new strategies to combat this devastating tumor is therefore paramount. Nanotechnology offers unique opportunities to develop innovative and more effective therapeutic approaches. However, most nanosystems developed to treat glioblastomas, especially those based on metallic nanoparticles (NPs), have proven unsuccessful due to their inability to efficiently target these tumors, which are particularly inaccessible due to the restrictions imposed by the blood-brain tumor barrier (BBTB). Here, an innovative strategy is presented to efficiently target metallic NPs to glioblastomas through glucose transporters (GLUT) overexpressed on the endothelial cells of glioblastoma microvasculature, particularly GLUT1. Specifically, Iron Oxide Nanoparticles (IONPs) are functionalized with glucuronic acid to promote GLUT-mediated transcytosis which is drastically boosted by inducing mild hypoglycemia. This metabolically-driven active targeting strategy has yielded unprecedented efficacy in targeting metallic NPs to glioblastomas. Moreover, these IONPs, designed to act as magnetic hyperthermia (MH) mediators, are used to conduct a proof-of-concept preclinical study on MRI-tracked MH therapy following intravenous administration, resulting in significant tumor growth delay. These findings demonstrate unparalleled efficiency in glioblastoma targeting and lay the ground for developing alternative therapeutic strategies to combat glioblastoma.

Convection-enhanced delivery of [177Lu]Lu-labeled gold nanoparticles combined with anti-PD1 checkpoint immunotherapy improves the survival of immunocompetent C57BL/6J mice with orthotopic GL261 murine glioma tumors

INTRODUCTION

Our objective was to study convection enhanced delivery (CED) of 177Lu-labeled metal chelating polymer (MCP) conjugated to gold nanoparticles ([177Lu]Lu-MCP-AuNP) alone or combined with anti-PD1 immune checkpoint inhibition (ICI) for improving the survival of immunocompetent C57BL/6J mice with orthotopic GL261 murine glioma tumors.

METHODS

C57BL/6J mice with GL261 tumors were treated with [177Lu]Lu-MCP-AuNP (0.8 or 2.7 MBq; 4 × 1011 AuNP) alone or combined with anti-PD1 antibodies (200 μg i.p. every 2 d × 3 doses). Control mice received normal saline, non-radioactive MCP-AuNP or anti-PD1 antibodies. Kaplan-Meier median survival was estimated. T-cell infiltration into the brain was probed by flow cytometry. Toxicity was assessed by monitoring body weight and cognitive function tests [Object Location Test (OLT) and Novel Object Recognition Test (NORT)] and T2-weighted MRI of the brain, overall health and ex vivo histopathological examination of the brain.

RESULTS

Treatment with [177Lu]Lu-MCP-AuNP (0.8 MBq) significantly increased median survival compared to MCP-AuNP (29 vs. 25 d; P = 0.007) or normal saline-treated mice (24 d; P < 0.001). Combining [177Lu]Lu-MCP-AuNP (0.8 MBq) with anti-PD1 antibodies increased median survival to 32 d (P < 0.0001 vs. normal saline). Increasing the mean amount of [177Lu]Lu-MCP-AuNP to 2.7 MBq and combining with anti-PD1 antibodies extended survival to at least 218 d in 5/9 mice. Increased CD8+ cytotoxic T-cells and decreased CD4+ helper T-cells were found in the brain vs. normal saline-treated mice. No weight loss (>20 %) was observed for treated or control mice. There was no change in cognitive function in mice treated with [177Lu]Lu-MCP-AuNP (0.8 MBq) alone or combined with anti-PD1 antibodies assessed by the OLT or NORT. T2-weighted MRI in mice treated with 2.7 MBq [177Lu]Lu-MCP-AuNP combined with anti-PD1 antibodies revealed edema, gliosis and ex vacuo dilatation of the ventricle proximal to the site of infusion. Histopathological examination of the brain revealed dilatation of the ventricle and gliosis proximal to the site of infusion but no radiation necrosis. MRI and histological analysis did not reveal tumor in the brain of these mice. Mice treated with 2.7 MBq [177Lu]Lu-MCP-AuNP combined with anti-PD1 antibodies did not demonstrate overall deleterious health effects.

CONCLUSIONS

We conclude that CED of [177Lu]Lu-MCP-AuNP combined with anti-PD1 checkpoint immunotherapy improved the survival of immunocompetent C67BL/6J mice with GL261 glioma tumors in the brain. Higher administered amounts of [177Lu]Lu-MCP-AuNP (2.7 MBq vs. 0.8 MBq) were most effective and yielded long-term survival.

ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE

This study demonstrates that combining a locally-infused radiation nanomedicine, [177Lu]Lu-MCP-AuNP and anti-PD1 checkpoint immunotherapy improved the survival of mice with glioma tumors in the brain. In the future, this treatment may be useful to treat residual tumor at the surgical margins in patients with GBM to prevent local recurrence and improve survival.

Mesenchymal-Type Genetic Mutations Are Likely Prerequisite for Glioblastoma Multiforme to Metastasize Outside the Central Nervous System: An Original Case Series and Systematic Review of the Literature

BACKGROUND

Glioblastoma multiforme (GBM) is the most aggressive and prevalent type of malignant brain tumor, yet it metastasizes outside the central nervous system (CNS) in only 0.4% of cases. Little is known about what enables this subset of GBMs to take root outside the CNS, but genetic mutations likely play a role.

METHODS

We conducted a PRISMA-compliant systematic review of metastatic GBM wherein we reviewed 3579 search results and 1080 abstracts, analyzing data from 139 studies and 211 unique patients. In addition, we describe 4 cases of patients with pathologically confirmed GBM metastases outside the CNS treated at our institution.

RESULTS

We found that metastases were discovered near previous surgical sites in at least 36.9% of cases. Other sites of metastasis included bone (47.9%), lung (25.6%), lymph nodes (25.1%), scalp (19.2%), and liver (14.2%). On average, metastases were diagnosed 12.1 months after the most recent resection, and the mean survival from discovery was 5.7 months. In our patients, primary GBM lesions showed mutations in NF1, TERT, TP53, CDK4, and RB1/PTEN genes. Unique to the metastatic lesions were amplifications in genes such as p53 and PDGFRA/KIT, as well as increased vimentin and Ki-67 expression.

CONCLUSIONS

There is strong evidence that GBMs acquire novel mutations to survive outside the CNS. In some cases, tumor cells likely mutate after seeding scalp tissue during surgery, and in others, they mutate and spread without surgery. Future studies and genetic profiling of primary and metastatic lesions may help uncover the mechanisms of spread.

Predicting glioblastoma progression using MR diffusion tensor imaging: A systematic review

BACKGROUND AND PURPOSE

Despite multimodal treatment of glioblastoma (GBM), recurrence beyond the initial tumor volume is inevitable. Moreover, conventional MRI has shortcomings that hinder the early detection of occult white matter tract infiltration by tumor, but diffusion tensor imaging (DTI) is a sensitive probe for assessing microstructural changes, facilitating the identification of progression before standard imaging. This sensitivity makes DTI a valuable tool for predicting recurrence. A systematic review was therefore conducted to investigate how DTI, in comparison to conventional MRI, can be used for predicting GBM progression.

METHODS

We queried three databases (PubMed, Web of Science, and Scopus) using the search terms: (diffusion tensor imaging OR DTI) AND (glioblastoma OR GBM) AND (recurrence OR progression). For included studies, data pertaining to the study type, number of GBM recurrence patients, treatment type(s), and DTI-related metrics of recurrence were extracted.

RESULTS

In all, 16 studies were included, from which there were 394 patients in total. Six studies reported decreased fractional anisotropy in recurrence regions, and 2 studies described the utility of connectomics/tractography for predicting tumor migratory pathways to a site of recurrence. Three studies reported evidence of tumor progression using DTI before recurrence was visible on conventional imaging.

CONCLUSIONS

These findings suggest that DTI metrics may be useful for guiding surgical and radiotherapy planning for GBM patients, and for informing long-term surveillance. Understanding the current state of the literature pertaining to these metrics' trends is crucial, particularly as DTI is increasingly used as a treatment-guiding imaging modality.

Longitudinal Psychological Distress After Malignant Brain Tumor Diagnosis: A Multilevel Analysis of Patients and Their Caregivers

OBJECTIVE

Malignant brain tumors are associated with debilitating symptoms and a poor prognosis, resulting in high psychological distress for patients and caregivers. There is a lack of longitudinal studies investigating psychological distress in this group. This study evaluated fear of progression (FoP), anxiety and depression in patients and their caregivers in the 6 months following malignant brain tumor diagnosis.

METHODS

This prospective, observational study assessed FoP (FoP-Q-SF[P]), anxiety and depression (HADS) at diagnosis (T0) and after three (T1) and 6 months (T2) in patients with malignant brain tumors (primary, secondary) and their caregivers. Multilevel analyses were used to examine changes over time and differences between patients and caregivers, while accounting for the interdependence in their distress values.

RESULTS

Seventy-one patients and 68 caregivers were included in the analysis. Throughout the study period, over 50% reported clinically relevant FoP, almost 50% reported clinically relevant anxiety, and over 30% reported relevant depression. Over all time points, caregivers reported significantly higher anxiety and depression than patients. Anxiety decreased between T0 and T2 in both groups. Exploratory analyses showed that female sex was associated with higher anxiety, and older age with higher depression. No significant predictors were identified for FoP.

CONCLUSION

A substantial number of patients and caregivers experience clinically relevant psychological distress in the 6 months following a malignant brain tumor diagnosis. Caregivers are particularly distressed, reporting higher anxiety and depression. Integrating psycho-oncological assessments and interventions for both patients and caregivers into clinical care is critical to address the psychological distress associated with malignant brain tumors.

A Wonderful Journey: The Diverse Roles of Adenosine Deaminase Action on RNA 1 (ADAR1) in Central Nervous System Diseases

BACKGROUND

Adenosine deaminase action on RNA 1 (ADAR1) can convert the adenosine in double-stranded RNA (dsRNA) molecules into inosine in a process known as A-to-I RNA editing. ADAR1 regulates gene expression output by interacting with RNA and other proteins; plays important roles in development, including growth; and is linked to innate immunity, tumors, and central nervous system (CNS) diseases.

RESULTS

In recent years, the role of ADAR1 in tumors has been widely discussed, but its role in CNS diseases has not been reviewed. It is worth noting that recent studies have shown ADAR1 has great potential in the treatment of neurodegenerative diseases, but the mechanisms are still unclear. Therefore, it is necessary to elaborate on the role of ADAR1 in CNS diseases.

CONCLUSIONS

Here, we focus on the effects and mechanisms of ADAR1 on CNS diseases such as Aicardi-AicardiGoutières syndrome, Alzheimer's disease, Parkinson's disease, glioblastoma, epilepsy, amyotrophic lateral sclerosis, and autism. We also evaluate the impact of ADAR1-based treatment strategies on these diseases, with a particular focus on the development and treatment strategies of new technologies such as microRNAs, nanotechnology, gene editing, and stem cell therapy. We hope to provide new directions and insights for the future development of ADAR1 gene editing technology in brain science and the treatment of CNS diseases.

Brain tumor and mood disorders: a retrospective analysis of anxiety and depression in patients with primary and metastatic brain tumors

Brain tumors are associated with a dismal prognosis, and the diagnosis often evokes significant psychological distress. However, the progression of emotional well-being throughout the clinical course of brain tumors remains poorly understood. This study aims to assess the prevalence of anxiety and depression in brain tumor patients and to identify the risk factors associated with postoperative emotional derangement in glioma and metastatic groups seperately. Psychological conditions were evaluated using the Hospital Anxiety and Depression Scale (HADS) at various preoperative and postoperative time points. A total of 159 patients who underwent surgery and HADS assessment between May 2018 and November 2020 were included in the analysis, comprising 112 glioma patients and 47 metastatic brain tumor patients. After surgery, the incidence of anxiety and depression increased in both the glioma and the metastatic brain tumor group. In both groups, tumors involving the frontal lobe were associated with a significant increase in postoperative HADS depression scores, whereas involvement of other lobes did not significantly affect postoperative HADS scores. Additionally, postoperative HADS scores did not differ significantly among gliomas of different grades. Among glioma patients, univariate analysis indicated that left-sided tumors were associated with an increased risk of postoperative depression worsening. In the metastatic group, a BMI > 24 was identified as a risk factor for postoperative anxiety exacerbation. The findings from this study highlight clinical characteristics associated with a higher risk of postoperative psychological disturbance, aiding in early prevention and tailored care to improve the quality of life for patients with intracranial tumors.

KDELR3 overexpression as a novel prognostic and diagnostic biomarker in glioma: comprehensive bioinformatic analysis insights

Glioma, the most prevalent primary intracranial malignancy among adults, is distinguished by its high morbidity and recurrence rates, posing a considerable threat to patients' quality of life and survival prospects. Consequently, the pursuit of efficacious molecular prognostic markers holds paramount importance. The exploration of the role of the KDELR3 kinase family in various neoplastic conditions constitutes an emerging area of research. However, the biological functions of KDELR3 and its prognostic implications in brain tumors remain largely undocumented. This study endeavored to ascertain the potential of KDELR3 as a prognostic indicator for glioma. We integrated a comprehensive dataset encompassing 1127 glioma samples, sourced from our cohort, The Cancer Genome Atlas (TCGA), and the Chinese Glioma Genome Atlas (CGGA), to delve into the expression patterns of KDELR3 in glioma and their associated implications. Notably, KDELR3 was markedly overexpressed in glioma and demonstrated a positive correlation with clinical progression. By utilizing Kaplan-Meier survival analysis and the Cox proportional hazards regression model, we evaluated the prognostic significance of KDELR3, revealing it as an independent predictor of adverse outcomes in glioma patients. Furthermore, gene set enrichment analysis unveiled potential signaling pathways associated with KDELR3 expression in glioma, primarily encompassing Cytokine-cytokine receptor interaction, extracellular matrix (ECM)-receptor interaction, and complement and coagulation cascades. In summation, our findings provide profound insights into the potential role of KDELR3 and its application as a novel and promising prognostic biomarker for glioma.

Unveiling the impact of Cancer-IgG on glioma: Insights into biological behavior and macrophage polarization dynamics

Gliomas are the most common malignant brain tumor in the central nervous system. They are characterized by high invasiveness and heterogeneity. In recent years, cancer-derived immunoglobulin G (Cancer-IgG) has received significant attention from researchers. Cancer-IgG, identified from tumors, can promote tumorigenesis and tumor progression. In this study, we explored the expression patterns of Cancer-IgG using available datasets and validated these patterns in our patient samples. Several loss-of-function and gain-of function assays were performed to investigate the roles of Cancer-IgG. Potential mechanisms underlying these roles were investigated using co-immunoprecipitation and RNA sequencing. Our result demonstrated that Cancer-IgG is expressed in gliomas. Furthermore, the expression of Cancer-IgG is associated with a poor prognosis and malignant molecular characterization. Functional assays confirmed that Cancer-IgG can promote glioma cells proliferation, migration, invasion, and resistant to apoptosis. The cGMP/PKG/VASP pathway is potentially involved in the effects of Cancer-IgG. Evidence from co-culture assay suggest that Cancer-IgG can induce M2 polarization of macrophages. In conclusion, Cancer-IgG can be identified in glioma cells and promotes the development of a malignant biological phenotype in vivo and in vitro. In glioma microenvironment, Cancer-IgG can induce M2 polarization of macrophages.

A detailed evaluation of the advantages among extracellular vesicles from three cell origins for targeting delivery of celastrol and treatment of glioblastoma

As one of the most common brain tumors, glioblastoma (GBM) lacks efficient therapeutic treatment and remains lethal. Extracellular vesicles (EVs) have emerged as a promising platform for GBM therapies. Nevertheless, the properties of EVs are significantly influenced by their cell origins. This study aimed to evaluate the advantages of EVs derived from bone marrow mesenchymal stem cells (BMSCs), human glioblastoma cells (U-87 MG) and macrophage cells (RAW264.7) to develop a more effective strategy for the delivery of anti-GBM drug celastrol (Cel). Three kinds of EVs exhibited spherical- or oval-shapes with an average size ranging from 90 to 140 nm. Western blot analysis confirmed the presence of specific EV markers (ALIX, CD63 or TSG101). Notably, the yield of BMSCs-derived EVs (BMSC-EVs) significantly surpassed that of U-87 MG and RAW264.7 cells. Furthermore, BMSC-EVs demonstrated the highest entrapment efficiency for Cel (72 %) and enhanced internalization into the target cells U-87 MG. The increased cytotoxicity and cell apoptosis further confirmed that Cel-loaded BMSC-EVs (BMSC-EVs-Cel) were more potent for killing U-87 MG cells compared with free Cel. In vivo studies utilizing both orthotopic and subcutaneous GBM models revealed facilitated blood-brain barrier penetration and transportation of cargo into tumor tissue by BMSC-EVs. Importantly, BMSC-EVs-Cel could effectively inhibit GBM growth, induce tumor tissue apoptosis and suppress intratumoral microvessel density in comparison with free Cel and temozolomide, while successfully decrease systemic toxicity. Overall, this study elucidates the properties of EVs derived from distinct cell origins and highlights the great potential of BMSC-EVs for brain tumor treatment.

Assessment of MGMT promoter methylation status in glioblastoma using deep learning features from multi-sequence MRI of intratumoral and peritumoral regions

OBJECTIVE

This study aims to evaluate the effectiveness of deep learning features derived from multi-sequence magnetic resonance imaging (MRI) in determining the O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status among glioblastoma patients.

METHODS

Clinical, pathological, and MRI data of 356 glioblastoma patients (251 methylated, 105 unmethylated) were retrospectively examined from the public dataset The Cancer Imaging Archive. Each patient underwent preoperative multi-sequence brain MRI scans, which included T1-weighted imaging (T1WI) and contrast-enhanced T1-weighted imaging (CE-T1WI). Regions of interest (ROIs) were delineated to identify the necrotic tumor core (NCR), enhancing tumor (ET), and peritumoral edema (PED). The ET and NCR regions were categorized as intratumoral ROIs, whereas the PED region was categorized as peritumoral ROIs. Predictive models were developed using the Transformer algorithm based on intratumoral, peritumoral, and combined MRI features. The area under the receiver operating characteristic curve (AUC) was employed to assess predictive performance.

RESULTS

The ROI-based models of intratumoral and peritumoral regions, utilizing deep learning algorithms on multi-sequence MRI, were capable of predicting MGMT promoter methylation status in glioblastoma patients. The combined model of intratumoral and peritumoral regions exhibited superior diagnostic performance relative to individual models, achieving an AUC of 0.923 (95% confidence interval [CI]: 0.890 - 0.948) in stratified cross-validation, with sensitivity and specificity of 86.45% and 87.62%, respectively.

CONCLUSION

The deep learning model based on MRI data can effectively distinguish between glioblastoma patients with and without MGMT promoter methylation.

A novel risk model consisting of nine platelet-related gene signatures for predicting prognosis, immune features and drug sensitivity in glioma

BACKGROUND

Glioma is a malignancy with challenging clinical treatment and poor prognosis. Platelets are closely associated with tumor growth, propagation, invasion, and angiogenesis. However, the role of platelet-related genes in glioma treatment and prognosis remains unclear.

RESULTS

A prognostic risk model was established using nine platelet-related prognostic signature genes (CAPG, CLIC1, GLB1, GNG12, KIF20A, PDIA4, SULF2, TAGLN2, and WEE1), and the risk score of samples were calculated. Subsequently, the glioma samples were divided into high- and low-risk groups based on the median values of risk scores. scRNA-seq analysis revealed that the prognostic genes were primarily located in astrocytes and natural killer cells. The immune infiltration proportions of most immune cells differed significantly between high- and low-risk groups. Moreover, we found AZD7762 as a potential candidate for glioma treatment.

CONCLUSION

Nine platelet-related prognostic genes identified as prognostic signatures for glioma were closely associated with the TME and may aid in directing the clinical treatment and prognosis of gliomas.

Detecting Tumor-Associated Intracranial Hemorrhage Using Proton Magnetic Resonance Spectroscopy

Intracranial hemorrhage associated with primary or metastatic brain tumors is a critical condition that requires urgent intervention, often through open surgery. Nevertheless, surgical interventions may not always be feasible due to two main reasons: (1) extensive hemorrhage can obscure the underlying tumor mass, limiting radiological assessment; and (2) intracranial hemorrhage may occasionally present as the first symptom of a brain tumor without prior knowledge of its existence. The current review of case studies suggests that advanced radiological imaging techniques can improve diagnostic power for tumoral hemorrhage. Adding proton magnetic resonance spectroscopy (1H-MRS), which profiles biochemical composition of mass lesions could be valuable: it provides unique information about tumor states distinct from hemorrhagic lesions bypassing the structural obliteration caused by the hemorrhage. Recent advances in 1H-MRS techniques may enhance the modality's reliability in clinical practice. This perspective proposes that 1H-MRS can be utilized in clinical settings to enhance diagnostic power in identifying tumors underlying intracranial hemorrhage.

Coffee and tea consumption and glioma risk: a meta-analysis of cohort studies

Background

Research on the association between glioma risk and coffee and tea consumption remains inconclusive. This study seeks to present a meta-analysis of the relationship between coffee and tea intake and glioma risk.

Method

Relevant cohort studies that collected coffee and tea exposure prospectively were identified through searches of the PubMed, Embase, and Scopus databases. Eligible studies included those providing adjusted relative risk estimates or hazard ratios (HRs) with 95% confidence intervals (CIs), or data sufficient for such calculations. Study quality was evaluated using the Newcastle-Ottawa Scale, while the GRADE system assessed the quality of evidence. The analysis explored glioma risk concerning the highest versus lowest levels of coffee and tea intake, supplemented by a dose-response evaluation using a one-stage robust error meta-regression model.

Results

A total of nine studies, published between 2004 and 2020, were included. In a model comparing the highest and lowest levels of coffee and tea consumption, 3,896 glioma cases were identified among 2,648,468 participants. Correspondingly, the pooled HRs with 95% CIs were 0.98 (0.87-1.09) for coffee and 0.95 (0.86-1.06) for tea, respectively. Furthermore, no evidence of publication bias was detected for either beverage. The dose-response analysis indicated a near "L"-shaped relationship between tea consumption and glioma risk, with the most notable risk reduction observed in individuals consuming more than 2.5 cups of tea per day. However, additional tea intake beyond this threshold did not confer evident risk reduction. According to Grade scoring system, the quality of meta-evidence was classified as "very low" for coffee and "low" for tea.

Conclusion

This meta-analysis provides evidence suggesting a potential inverse association between tea consumption and glioma risk, while no such association was observed for coffee consumption. Given that the evidence for coffee was classified as "very low" and for tea as "low," cautious interpretation of the findings is warranted, and further research is needed to validate these results.

Machine Learning-based Prognostic Subgrouping of Glioblastoma: A Multi-center Study

BACKGROUND

Glioblastoma is the most aggressive adult primary brain cancer, characterized by significant heterogeneity, posing challenges for patient management, treatment planning, and clinical trial stratification.

METHODS

We developed a highly reproducible, personalized prognostication and clinical subgrouping system using machine learning (ML) on routine clinical data, MRI, and molecular measures from 2,838 demographically diverse patients across 22 institutions and 3 continents. Patients were stratified into favorable, intermediate, and poor prognostic subgroups (I, II, III) using Kaplan-Meier analysis (Cox proportional model and hazard ratios [HR]).

RESULTS

The ML model stratified patients into distinct prognostic subgroups with HRs between subgroups I-II and I-III of 1.62 (95%CI: 1.43-1.84, p<0.001) and 3.48 (95%CI: 2.94-4.11, p<0.001), respectively. Analysis of imaging features revealed several tumor properties contributing unique prognostic value, supporting the feasibility of a generalizable prognostic classification system in a diverse cohort.

CONCLUSIONS

Our ML model demonstrates extensive reproducibility and online accessibility, utilizing routine imaging data rather than complex imaging protocols. This platform offers a unique approach for personalized patient management and clinical trial stratification in glioblastoma.

Bioprinting of a multi-composition array to mimic intra-tumor heterogeneity of glioblastoma for drug evaluation

Microextrusion printing is widely used to precisely manufacture microdevices, microphysiological systems, and biological constructs that feature micropatterns and microstructures consisting of various materials. This method is particularly useful for creating biological models that recapitulate in vivo-like cellular microenvironments. Although there is a recent demand for high-throughput data from a single in vitro system, it remains challenging to fabricate multiple models with a small volume of bioinks in a stable and precise manner due to the spreading and evaporation issues of the extruded hydrogel. As printing time increases, the extruded bioink spreads and evaporates, leading to technical problems that decrease printing resolution and stability, as well as biological problems that affect 3D culture space and cell viability. In this study, we describe a novel microextrusion bioprinting technique to stably fabricate a multi-composition array consisting of massive and nanoliter-scale hydrogel dots by using multi-bioink printing and aerosol-based crosslinking techniques to prevent spreading and evaporation issues. We confirmed that the crosslinking aerosol effectively prevented spreading and evaporation by analyzing the morphological changes of the extruded hydrogel. By adjusting the extruding ratio of the bioinks, we were able to print a multi-composition array. This stable and massive array printing technique allowed us to improve the replicates of biological models and provide various data from a single culture system. The array printing technique was applied to recapitulate the intra-tumor heterogeneity of glioblastoma and assess temozolomide efficacy on the array model.

Optimal control of combination immunotherapy for a virtual murine cohort in a glioblastoma-immune dynamics model

The immune checkpoint inhibitor anti-PD-1, commonly used in cancer immunotherapy, has not been successful as a monotherapy for the highly aggressive brain cancer glioblastoma. However, when used in conjunction with a CC-chemokine receptor-2 (CCR2) antagonist, anti-PD-1 has shown efficacy in preclinical studies. In this paper, we aim to optimize treatment regimens for this combination immunotherapy using optimal control theory. We extend a treatment-free glioblastoma-immune dynamics ODE model to include interventions with anti-PD-1 and the CCR2 antagonist. An optimized regimen increases the survival of an average mouse from 32 days post-tumor implantation without treatment to 111 days with treatment. We scale this approach to a virtual murine cohort to evaluate mortality and quality of life concerns during treatment, and predict survival, tumor recurrence, or death after treatment. A parameter identifiability analysis identifies five parameters suitable for personalizing treatment within the virtual cohort. Sampling from these five practically identifiable parameters for the virtual murine cohort reveals that personalized, optimized regimens enhance survival: 84% of the virtual mice survive to day 100, compared to 60% survival in a previously studied experimental regimen. Subjects with high tumor growth rates and low T cell kill rates are identified as more likely to die during and after treatment due to their compromised immune systems and more aggressive tumors. Notably, the MDSC death rate emerges as a long-term predictor of either disease-free survival or death.

Multi-omics integration analysis reveals the role of N6-methyladenosine in lncRNA translation during glioma stem cell differentiation

Glioblastoma is one of the most lethal brain diseases in humans. Although recent studies have shown reciprocal interactions between N6-methyladenosine (m6A) modifications and long noncoding RNAs (lncRNAs) in gliomagenesis and malignant progression, the mechanism of m6A-mediated lncRNA translational regulation in glioblastoma remains unclear. Herein, we profiled the transcriptomes, translatomes, and epitranscriptomics of glioma stem cells and differentiated glioma cells to investigate the role of m6A in lncRNA translation comprehensively. We found that lncRNAs with numerous m6A peaks exhibit reduced translation efficiency. Transcript-level expression analysis demonstrates an enrichment of m6A around short open reading frames (sORFs) of translatable lncRNA transcripts. Further comparison analysis of m6A modifications in different RNA regions indicates that m6A peaks downstream of sORFs inhibit lncRNA translation more than those upstream. Observations in glioma-associated lncRNAs H19, LINC00467, and GAS5 further confirm the negative effect of m6A methylation on lncRNA translation. Overall, these findings elucidate the dynamic profiles of the m6A methylome and enhance the understanding of the complexity of lncRNA translational regulation.

Interferon regulatory factor 8-driven reprogramming of the immune microenvironment enhances antitumor adaptive immunity and reduces immunosuppression in murine glioblastoma

BACKGROUND

Glioblastoma (GBM) has a highly immunosuppressive tumor immune microenvironment (TIME), largely mediated by myeloid-derived suppressor cells (MDSCs). Here, we utilized a retroviral replicating vector (RRV) to deliver Interferon Regulatory Factor 8 (IRF8), a master regulator of type 1 conventional dendritic cell (cDC1) development, in a syngeneic murine GBM model. We hypothesized that RRV-mediated delivery of IRF8 could "reprogram" intratumoral MDSCs into antigen-presenting cells and thereby restore T-cell responses.

METHODS

Effects of RRV-IRF8 on survival and tumor growth kinetics were examined in the SB28 murine GBM model. The immunophenotype was analyzed by flow cytometry and gene expression assays. We assayed functional immunosuppression and antigen presentation by ex vivo T-cell-myeloid co-culture.

RESULTS

Intratumoral injection of RRV-IRF8 in mice bearing intracerebral SB28 glioma significantly suppressed tumor growth and prolonged survival. RRV-IRF8 treated tumors exhibited significant enrichment of cDC1s and CD8+ T-cells. Additionally, myeloid cells derived from RRV-IRF8 tumors showed decreased expression of the immunosuppressive markers Arg1 and IDO1 and demonstrated reduced suppression of naïve T-cell proliferation in ex vivo co-culture, compared to controls. Furthermore, DCs from RRV-IRF8 tumors showed increased antigen presentation compared to those from control tumors. In vivo treatment with azidothymidine (AZT), a viral replication inhibitor, showed that IRF8 transduction in both tumor and non-tumor cells is necessary for survival benefit, associated with a reprogrammed, cDC1- and CD8 T-cell-enriched TIME.

CONCLUSIONS

Our results indicate that reprogramming of glioma-infiltrating myeloid cells by in vivo expression of IRF8 may reduce immunosuppression and enhance antigen presentation, achieving improved tumor control.

Longikaurin A induces ferroptosis and inhibits glioblastoma progression through DNA methylation - Mediated GPX4 suppression

Glioblastoma (GBM) is the most common primary intracranial tumor highly resistant to conventional clinical chemotherapy. Recently, the induction of ferroptosis is emerging as a putative strategy to treat various tumors. However, the identification of the effective and applicable tumor ferroptosis-inducing agents remains challenging. In this study, we showed that longikaurin A (LK-A), a natural diterpenoid isolated from the medicinal plant Isodon ternifolius with strong anti-GBM capacities, induced remarkable GBM cell ferroptosis along with suppressing the key anti-ferroptosis factor glutathione peroxidase 4 (GPX4). GPX4 promoter contains conserved CpG islands. The LK-A-induced GPX4 suppression coincided with the inhibition of ten-eleven translocation 2 (TET2), a key DNA demethylation enzyme and an increase in the hypermethylation of the GPX4 promoter. Further, LK-A promoted the GBM ferroptotic alterations and inhibited GBM progression in both subcutaneous and orthotopic xenograft mouse models, whereas GPX4 overexpression largely abrogated its anti-GBM effects both in vitro and in vivo, suggesting that LK-A inductions of the DNA methylation-incurred GPX4 suppression and ferroptosis are crucial for its anti-GBM functions. Together, our study has elaborated an important epigenetic pathway of GBM ferroptosis and uncovered a critical pharmacological property of LK-A for treating GBM patients.

Hydrogel Applications in the Diagnosis and Treatment of Glioblastoma

Glioblastoma multiforme (GBM), a common malignant neurological tumor, has boundaries indistinguishable from those of normal tissue, making complete surgical removal ineffective. The blood-brain barrier (BBB) further impedes the efficacy of radiotherapy and chemotherapy, leading to suboptimal treatment outcomes and a heightened probability of recurrence. Hydrogels offer multiple advantages for GBM diagnosis and treatment, including overcoming the BBB for improved drug delivery, controlled drug release for long-term efficacy, and enhanced relaxation properties of magnetic resonance imaging (MRI) contrast agents. Hydrogels, with their excellent biocompatibility and customizability, can mimic the in vivo microenvironment, support tumor cell culture, enable drug screening, and facilitate the study of tumor invasion and metastasis. This paper reviews the classification of hydrogels and recent research for the diagnosis and treatment of GBM, including their applications as cell culture platforms and drugs including imaging contrast agents carriers. The mechanisms of drug release from hydrogels and methods to monitor the activity of hydrogel-loaded drugs are also discussed. This review is intended to facilitate a more comprehensive understanding of the current state of GBM research. It offers insights into the design of integrated hydrogel-based GBM diagnosis and treatment with the objective of achieving the desired therapeutic effect and improving the prognosis of GBM.

Treatment Options for IDH-Mutant Malignant Gliomas

OPINION STATEMENT

As the peak incidence of isocitrate dehydrogenase (IDH)-mutant gliomas is amongst young adults, there is a need to balance tumor control with long term side effects of therapy. Following initial clinical presentation and acquisition of contrasted diagnostic imaging, tissue diagnosis is essential in suspected diffuse glioma. Depending on the location and extent of disease, maximal surgical resection is preferred both for histologic diagnosis and initial therapy. Partial resection or biopsy alone is considered when the tumor cannot be completely resected or if there are clinical reservations regarding a more significant operation. The classification of diffuse glioma has evolved over time, with histopathology and molecular marker status guiding discussions of prognosis and postoperative management. In patients with IDH-mutant grade 2 glioma and low-risk features, observation with active surveillance is generally recommended following a gross total resection. For those with high-risk features, which historically included age > 40 years or subtotal resection, adjuvant chemotherapy and radiation therapy are generally recommended, however decisions for adjuvant therapy pose challenges as many of the landmark historical trials guiding adjuvant therapy were performed prior to the molecularly defined era. This is an area where multiple clinical trials are ongoing and hold promise to inform treatment paradigms, including recent data on the use of IDH-mutant inhibitors in grade 2 tumors with recurrent or residual disease. For IDH-mutant grade 3 and 4 glioma, adjuvant chemotherapy and radiation are recommended for all patients after initial resection.

An update on the role of focused ultrasound in neuro-oncology

PURPOSE OF REVIEW

Brain tumor treatment presents challenges for patients and clinicians, with prognosis for many of the most common brain tumors being poor. Focused ultrasound (FUS) can be deployed in several ways to circumvent these challenges, including the need to penetrate the blood-brain barrier and spare healthy brain tissue. This article reviews current FUS applications within neuro-oncology, emphasizing ongoing or recently completed clinical trials.

RECENT FINDINGS

Most clinical interest in FUS for neuro-oncology remains focused on exploring BBB disruption to enhance the delivery of standard-of-care therapeutics. More recently, the application of FUS for radiosensitization, liquid biopsy, and sonodynamic therapy is garnering increased clinical attention to assist in tumor ablation, early detection, and phenotypic diagnosis. Preclinical studies show encouraging data for the immunomodulatory effects of FUS, but these findings have yet to be tested clinically.

SUMMARY

FUS is a burgeoning area of neuro-oncology research. Data from several forthcoming large clinical trials should help clarify its role in neuro-oncology care.

Dietary Recommendations for Glioma: A Mini-Review

PURPOSE OF REVIEW

Glioma is the most common type of brain cancer, associated with a high mortality rate. Diet is one of the most modifiable factors that can influence the risk of various cancers, including glioma. While the relationship between diet and glioma has been explored in recent years, the number of studies in this area remains limited, and the findings are often controversial. Moreover, all existing studies are observational, which means they may be influenced by a range of confounding variables. In this mini-review, we aim to provide a comprehensive and informative overview of the dietary recommendations related to glioma that have been published to date.

RECENT FINDINGS

Research suggests that adherence to healthy dietary patterns-such as the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH) diet, Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, Paleolithic diet, high-protein dietary patterns, and vegetarian dietary patterns-may be associated with a reduced risk of glioma. These diets are rich in phytochemicals and antioxidants. Additionally, certain food groups, including fruits, vegetables, legumes, nuts, eggs, fresh fish, tea, and coffee, are emphasized for their protective effects against glioma. Conversely, adherence to unhealthy dietary patterns, such as the Western diet, or diets with high inflammatory potential, glycemic and insulinemic loads, and high consumption of grains (especially refined grains), processed meats, and processed fish, has been linked to an increased risk of glioma. Current studies suggest that following a healthy diet may reduce the odds of developing glioma. However, due to the limited number of studies and the observational nature of the existing research, further investigations with more robust designs, such as randomized controlled trials, are needed to clarify these associations.