Search

Telmisartan, an angiotensin II type 1 receptor (AT1R) blocker, exhibits broad anti-tumor activity. However, in vitro, anti-proliferative effects are shown at doses far beyond the therapeutic plasma concentration. Considering the role of tumor microenvironment in glioma progression, glioma-astrocyte co-cultures were employed to test the anti-tumor potential of low-dose telmisartan. When a high dose was required for a direct anti-proliferative effect on glioma cell lines, a low dose significantly inhibited glioma cell proliferation and migration in the co-culture system. Under co-culture conditions, upregulated IL-6 expression in astrocytes played a critical role in glioma progression. Silencing IL-6 in astrocytes or IL-6R in glioma cells reduced proliferation and migration. Telmisartan (5 μM) inhibited astrocytic IL-6 expression, and its anti-tumor effects were reversed by silencing IL-6 or IL-6R and inhibiting signal transducer and activator of transcription 3 (STAT3) activity in glioma cells. Moreover, the telmisartan-driven IL-6 downregulation was not imitated by losartan, an AT1R blocker with little capacity of peroxisome proliferator-activated receptor-gamma (PPARγ) activation, but was eliminated by a PPARγ antagonist, indicating that the anti-glioma effects of telmisartan rely on its PPARγ agonistic activity rather than AT1R blockade. This study highlights the importance of astrocytic IL-6-mediated paracrine signaling in glioma growth and the potential of telmisartan as an adjuvant therapy for patients with glioma, especially those with hypertension., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Immunotherapy has revolutionized the treatment of various types of tumors, but there has been no breakthrough in the treatment of gliomas. The aim of this study is to discover valuable immunotherapy target in glioma, analyze its expression in glioma and the related microenvironment, explore potential immunotherapy strategies, and propose new possibilities for the treatment of gliomas., Methods: Immunohistochemistry (IHC) and multiplex fluorescence immunohistochemistry (mIHC) were used to analyze the expression of common immune markers and checkpoints in 187 glioma patients from Sun Yat-sen University Caner Center (SYSUCC). Bioinformatics analysis was used to examine the expression of TIM-3 in different macrophages using the Chinese Glioma Genome Atlas (CGGA) single-cell sequencing database. The Kaplan-Meier curve was used to predict the prognostic value of samples with high TIM-3 and CD68 expression. The R package was used to analyze the somatic mutation status and the sensitivity of small molecule inhibitors in TIM-3/CD68 double-high expression samples., Results: TIM-3 is a relatively highly expressed immune checkpoint in glioma. Unlike other tumors, TIM-3 is mainly expressed on macrophages in the glioma microenvironment. TIM-3/CD68 double-high expression suggests poor survival in glioma and may be a new upgrade marker in both IDH-mutant glioma and IDH-wildtype low-grade glioma (LGG) glioma (P < 0.01). Exploring the combination of TIM-3 inhibitors and p38 MAPK inhibitor may be a potential treatment direction for TIM-3/CD68 double high expression gliomas in the future., Conclusions: The combination of TIM-3 and CD68 holds significant importance as a potential target for both prognosis and therapeutic intervention in glioma., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Glioma is the most common brain tumor. IDH mutations occur frequently in glioma, indicating a more favorable prognosis. We aimed to explore energy metabolism-related genes in glioma to promote the research and treatment., Methods: Datasets were obtained from TCGA and GEO databases. Candidate genes were screened by differential gene expression analysis, then functional enrichment analysis was conducted on the candidate genes. PPI was also carried out to help determine the target gene. GSEA and DO analysis were conducted in the different expression level groups of the target gene. Survival analysis and immune cell infiltrating analysis were performed as well., Results: We screened 34 candidate genes and selected GLUD1 as the target gene. All candidate genes were significantly enriched in 10 KEGG pathways and 330 GO terms. GLUD1 expression was higher in IDH-mutant samples than IDH-wildtype samples, and higher in normal samples than tumor samples. Low GLUD1 expression was related to poor prognosis according to survival analysis. Most types of immune cells were negatively related to GLUD1 expression, but monocytes and activated mast cells exhibited significantly positive correlation with GLUD1 expression. GLUD1 expression was significantly related to 119 drugs and 6 immune checkpoint genes. GLUD1 was able to serve as an independent prognostic indicator of IDH-mutant glioma., Conclusion: In this study, we identified an energy metabolism-related gene GLUD1 potentially contributing to favorable clinical outcomes of IDH-mutant glioma. In glioma, GLUD1 related clinical outcomes and immune landscape were clearer, and more valuable information was provided for immunotherapy., (© 2024. The Author(s).)

Microbubble-enhanced ultrasound provides a noninvasive physical method to locally overcome major obstacles to the accumulation of blood-borne therapeutics in the brain, posed by the blood-brain barrier (BBB). However, due to the highly nonlinear and coupled behavior of microbubble dynamics in brain vessels, the impact of microbubble resonant effects on BBB signaling and function remains undefined. Here, combined theoretical and prospective experimental investigations reveal that microbubble resonant effects in brain capillaries can control the enrichment of inflammatory pathways that are sensitive to wall shear stress and promote differential expression of a range of transcripts in the BBB, supporting the notion that microbubble dynamics exerted mechanical stress can be used to establish molecular, in addition to spatial, therapeutic windows to target brain diseases. Consistent with these findings, a robust increase in cytotoxic T-cell accumulation in brain tumors was observed, demonstrating the functional relevance and potential clinical significance of the observed immuno-mechano-biological responses., (© 2024. The Author(s).)

Oligodendroglioma, IDH-mutant and 1p/19q-codeleted has highly variable outcomes that are strongly influenced by patient age. The distribution of oligodendroglioma age is non-Gaussian and reportedly bimodal, which motivated our investigation of age-associated molecular alterations that may drive poorer outcomes. We found that elevated HOXD12 expression was associated with both older patient age and shorter survival in the TCGA (FDR < 0.01, FDR = 1e-5) and the CGGA (p = 0.03, p < 1e-3). HOXD12 gene body hypermethylation was associated with older age, higher WHO grade, and shorter survival in the TCGA (p < 1e-6, p < 0.001, p < 1e-3) and with older age and higher WHO grade in Capper et al. (p < 0.002, p = 0.014). In the TCGA, HOXD12 gene body hypermethylation and elevated expression were independently prognostic of NOTCH1 and PIK3CA mutations, loss of 15q, MYC activation, and standard histopathological features. Single-nucleus RNA and ATAC sequencing data showed that HOXD12 activity was elevated in neoplastic tissue, particularly within cycling and OPC-like cells, and was associated with a stem-like phenotype. A pan-HOX DNA methylation analysis revealed an age and survival-associated HOX-high signature that was tightly associated with HOXD12 gene body methylation. Overall, HOXD12 expression and gene body hypermethylation were associated with an older, atypically aggressive subtype of oligodendroglioma., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Malignant transformation (MT) is commonly seen in IDH-mutant gliomas. There has been a growing research interest in revealing its underlying mechanisms and intervening prior to MT at the early stages of the transforming process. Here we established a unique pair of matched 3D cell models: 403L, derived from a low-grade glioma (LGG), and 403H, derived from a high-grade glioma (HGG), by utilizing IDH-mutant astrocytoma samples from the same patient when the tumor was diagnosed as WHO grade 2 (tumor mutational burden (TMB) of 3.96/Mb) and later as grade 4 (TMB of 70.07/Mb), respectively. Both cell models were authenticated to a patient's sample retaining endogenous expression of IDH1 R132H. DNA methylation profiles of the parental tumors referred to LGG and HGG IDH-mutant glioma clusters. The immunopositivity of SOX2, NESTIN, GFAP, OLIG2, and beta 3-Tubulin suggested the multilineage potential of both models. 403H was more prompt to cell invasion and developed infiltrative HGG in vivo. The differentially expressed genes (DEGs) from the RNA sequencing analysis revealed the tumor invasion and aggressiveness related genes exclusively upregulated in the 403H model. Pathway analysis showcased an enrichment of genes associated with epithelial-mesenchymal transition (EMT) and Notch signaling pathways in 403H and 403L, respectively. Mass spectrometry-based targeted metabolomics and hyperpolarized (HP) 1- 13 C pyruvate in-cell NMR analyses demonstrated significant alterations in the TCA cycle and fatty acid metabolism. Citrate, glutamine, and 2-HG levels were significantly higher in 403H. To our knowledge, this is the first report describing the development of a matched pair of 3D patient-derived cell models representative of MT and temozolomide (TMZ)-induced hypermutator phenotype (HMP) in IDH-mutant glioma, providing insights into genetic and metabolic changes during MT/HMP. This novel in vitro model allows further investigation of the mechanisms of MT at the cellular level., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: Family with sequence similarity 109, member B (FAM109B) is involved in endocytic transport and affects genetic variation in brain methylation. It is one of the important genes related to immune cell-associated diseases. In the tumor immune system, methylation can regulate tumor immunity and influence the maturation and functional response of immune cells. Whether FAM109B is involved in tumor progression and its correlation with the tumor immune microenvironment has not yet been disclosed., Methods: A comprehensive pan-cancer analysis of FAM109B expression, prognosis, immunity, and TMB was conducted. The expression, clinical features, and prognostic value of FAM109B in low-grade gliomas (LGG) were evaluated using TCGA, CGGA, and Gravendeel databases. The expression of FAM109B was validated by qRT-PCR, immunohistochemistry (IHC), and Western blotting (WB). The relationship between FAM109B and methylation, Copy Number Variation (CNV), prognosis, immune checkpoints (ICs), and common chemotherapy drug sensitivity in LGG was explored through Cox regression, Kaplan-Meier curves, and Spearman correlation analysis. FAM109B levels and their distribution were studied using the TIMER database and single-cell analysis. The potential role of FAM109B in gliomas was further investigated through in vitro and in vivo experiments., Results: FAM109B was significantly elevated in various tumor types and was associated with poor prognosis. Its expression was related to aggressive progression and poor prognosis in low-grade glioma patients, serving as an independent prognostic marker for LGG. Glioma grade was negatively correlated with FAM109B DNA promoter methylation. Immune infiltration and single-cell analysis showed significant expression of FAM109B in tumor-associated macrophages (TAMs). The expression of FAM109B was closely related to gene mutations, immune checkpoints (ICs), and chemotherapy drugs in LGG. In vitro studies showed increased FAM109B expression in LGG, closely related to cell proliferation. In vivo studies showed that mice in the sh-FAM109B group had slower tumor growth, slower weight loss, and longer survival times., Conclusions: FAM109B, as a novel prognostic biomarker for low-grade gliomas, exhibits specific overexpression in TAMs and may be a potential therapeutic target for LGG patients., (© 2024. The Author(s).)

Glioblastoma (GBM) remains the most lethal primary brain tumor, characterized by dismal survival rates. Novel molecular targets are urgently required to enhance therapeutic outcomes. A combination of bioinformatics analysis and experimental validation was employed to investigate the role of EGFLAM in GBM. The Chinese Glioma Genome Atlas provided a platform for gene expression profiling, while siRNA-mediated knockdown and overexpression assays in GBM cell lines, alongside in vivo tumorigenesis models, facilitated functional validation. EGFLAM was found to be significantly overexpressed in GBM tissues, correlating with adverse prognostic factors and higher tumor grades, particularly in patients over the age of 41. Functional assays indicated that EGFLAM is vital for maintaining GBM cell proliferation, viability, and invasiveness. Knockdown of EGFLAM expression led to a marked decrease in tumorigenic capabilities. Proteomic interactions involving EGFLAM, such as with NUP205, were implicated in cell cycle regulation, providing insight into its oncogenic mechanism. In vivo studies further demonstrated that silencing EGFLAM expression could inhibit tumor growth, underscoring its therapeutic potential. The study identifies EGFLAM as a pivotal oncogenic factor in GBM, serving as both a prognostic biomarker and a viable therapeutic target. These findings lay the groundwork for future research into EGFLAM-targeted therapies, aiming to improve clinical outcomes for GBM patients., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Tumor-associated neutrophil (TAN) effects on glioblastoma (GBM) biology remain under-characterized. We show here that neutrophils with dendritic features-including morphological complexity, expression of antigen presentation genes, and the ability to process exogenous peptide and stimulate major histocompatibility complex (MHC)II-dependent T cell activation-accumulate intratumorally and suppress tumor growth in vivo. Trajectory analysis of patient TAN scRNA-seq identifies this "hybrid" dendritic-neutrophil phenotype as a polarization state that is distinct from canonical cytotoxic TANs, and which differentiates from local precursors. These hybrid-inducible immature neutrophils-which we identified in patient and murine glioblastomas-arise not from circulation, but from local skull marrow. Through labeled skull flap transplantation and targeted ablation, we characterize calvarial marrow as a contributor of antitumoral myeloid antigen-presenting cells (APCs), including TANs, which elicit T cell cytotoxicity and memory. As such, agents augmenting neutrophil egress from skull marrow-such as intracalvarial AMD3100, whose survival-prolonging effect in GBM we report-present therapeutic potential., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

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 (Na v ) in GSCs, particularly focusing on its cell cycle-dependent functional expression. Na v 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 Na v in regulating GBM stemness were investigated through pathway analysis in vitro and through tumor proliferation assay in vivo., Results: We demonstrated that Na v 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 Na v 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 Na v substantially influenced the self-renewal and multipotency features of GSCs, concomitantly enhancing their degree of differentiation. Finally, our data suggested that Na v 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 Na v ., Conclusions: This insight positions Na v as a promising prognostic biomarker and therapeutic target for GBM patients, particularly in conjunction with temozolomide treatment., (© 2024. The Author(s).)

Glioblastoma remains one of the deadliest brain malignancies. First-line therapy consists of maximal surgical tumor resection, accompanied by chemotherapy and radiotherapy. Malignant cells escape surgical resection by migrating into the surrounding healthy brain tissue, where they give rise to the recurrent tumor. Based on gene expression, tumor cores can be subtyped into mesenchymal, proneural, and classical tumors, each being associated with differences in genetic alterations and cellular composition. In contrast, the adjacent brain parenchyma where infiltrating malignant cells escape surgical resection is less characterized in patients. Using spatial transcriptomics (n = 11), we show that malignant cells within proneural or mesenchymal tumor cores display spatially organized differences in gene expression, although such differences decrease within the infiltrated brain tissue. Malignant cells residing in infiltrated brain tissue have increased expression of genes related to neurodevelopmental pathways and glial cell differentiation. Our findings provide an updated view of the spatial landscape of glioblastomas and further our understanding of the malignant cells that infiltrate the healthy brain, providing new avenues for the targeted therapy of these cells after surgical resection., (© 2024. The Author(s).)

Gliomas are highly malignant brain tumours that remain refractory to treatment. Treatment is typically surgical intervention followed by concomitant temozolomide and radiotherapy; however patient prognosis remains poor. Voltage gated ion channels have emerged as novel targets in cancer therapy and inhibition of a potassium selective subtype (hERG, Kv11.1) has demonstrated antitumour activity. Unfortunately blockade of hERG has been limited by cardiotoxicity, however hERG channel agonists have produced similar chemotherapeutic benefit without significant side effects. In this study, electrophysiological recordings suggest the presence of hERG channels in the anaplastic astrocytoma cell line SMA-560, and treatment with the hERG channel agonist NS1643, resulted in a significant reduction in the proliferation of SMA-560 cells. In addition, NS1643 treatment also resulted in a reduction of the secretion of matrix metalloproteinase-9 and SMA-560 cell migration. When combined with temozolomide, an additive impact was observed, suggesting that NS1643 may be a suitable adjuvant to temozolomide and limit the invasiveness of glioma., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Benn et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Gliomas are highly complex and metabolically active brain tumors associated with poor prognosis. Recent reports have found altered levels of blood metabolites during early tumor development, suggesting that tumor development could be detected several years before clinical manifestation. In this study, we performed metabolite analyses of blood samples collected from healthy controls and future glioma patients, up to eight years before glioma diagnosis, and on the day of glioma surgery. We discovered that metabolites related to early glioma development were associated with an increased energy turnover, as highlighted by elevated levels of TCA-related metabolites such as fumarate, malate, lactate and pyruvate in pre-diagnostic cases. We also found that metabolites related to glioma progression at surgery were primarily high levels of amino acids and metabolites of amino acid catabolism, with elevated levels of 11 amino acids and two branched-chain alpha-ketoacids, ketoleucine and ketoisoleucine. High amino acid turnover in glioma tumor tissue is currently utilized for PET imaging, diagnosis and delineation of tumor margins. By examining blood-based metabolic progression patterns towards disease onset, we demonstrate that this high amino acid turnover is also detectable in a simple blood sample. These findings provide additional insight of metabolic alterations during glioma development and progression., (© 2024. The Author(s).)

Glioblastoma (GBM) represents an aggressive brain tumor, characterized by intra- and inter-tumoral heterogeneity and therapy resistance, leading to unfavourable prognosis. An increasing number of studies pays attention on the regulation of ferroptosis, an iron-dependent cell death, as a strategy to reverse drug resistance in cancer. However, the debate on whether this strategy may have important implications for the treatment of GBM is still ongoing. In the present study, we used ferric ammonium citrate and erastin to evaluate ferroptosis induction effects on two human GBM cell lines, U-251 MG, with proneural characteristics, and T98-G, with a mesenchymal profile. The response to ferroptosis induction was markedly different between cell lines, indeed T98-G cells showed an enhanced antioxidant defence, with increased glutathione levels, as compared to U-251 MG cells. Moreover, using bioinformatic approaches and analysing publicly available datasets from patients' biopsies, we found that GBM with a mesenchymal phenotype showed an up-regulation of several genes involved in antioxidant mechanisms as compared to proneural subtype. Thus, our results suggest that GBM subtypes differently respond to ferroptosis induction, emphasizing the significance of further molecular studies on GBM to better discriminate between various tumor subtypes and progressively move towards personalized therapy., (© 2024. The Author(s).)

Background: The high fatality rate of glioblastoma (GBM) is attributed to glioblastoma stem cells (GSCs), which exhibit heterogeneity and therapeutic resistance. Metabolic plasticity of mitochondria is the hallmark of GSCs. Targeting mitochondrial biogenesis of GSCs is crucial for improving clinical prognosis in GBM patients., Methods: SMYD2-induced PGC1α methylation and followed nuclear export are confirmed by co-immunoprecipitation, cellular fractionation, and immunofluorescence. The effects of SMYD2/PGC1α/CRM1 axis on GSCs mitochondrial biogenesis are validated by oxygen consumption rate, ECAR, and intracranial glioma model., Results: PGC1α methylation causes the disabled mitochondrial function to maintain the stemness, thereby enhancing the radio-resistance of GSCs. SMYD2 drives PGC1α K224 methylation (K224me), which is essential for promoting the stem-like characteristics of GSCs. PGC1α K224me is preferred binding with CRM1, accelerating PGC1α nuclear export and subsequent dysfunction. Targeting PGC1α methylation exhibits significant radiotherapeutic efficacy and prolongs patient survival., Conclusions: These findings unveil a novel regulatory pathway involving mitochondria that govern stemness in GSCs, thereby emphasizing promising therapeutic strategies targeting PGC1α and mitochondria for the treatment of GBM., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Glioblastoma (GBM) is a highly aggressive tumor with unmet therapeutic needs, which can be explained by extensive intra-tumoral heterogeneity and plasticity. In this study, we aimed to investigate the specific metabolic features of Glioblastoma stem cells (GSC), a rare tumor subpopulation involved in tumor growth and therapy resistance., Methods: We conducted comprehensive analyses of primary patient-derived GBM cultures and GSC-enriched cultures of human GBM cell lines using state-of-the-art molecular, metabolic, and phenotypic studies., Results: We showed that GSC-enriched cultures display distinct glycolytic profiles compared with differentiated tumor cells. Further analysis revealed that GSC relies on pyruvate carboxylase (PC) activity for survival and self-renewal capacity. Interestingly, inhibition of PC led to GSC death, particularly when the glutamine pool was low, and increased differentiation. Finally, while GSC displayed resistance to the chemotherapy drug etoposide, genetic or pharmacological inhibition of PC restored etoposide sensitivity in GSC, both in vitro and in orthotopic murine models., Conclusions: Our findings demonstrate the critical role of PC in GSC metabolism, survival, and escape to etoposide. They also highlight PC as a therapeutic target to overcome therapy resistance in GBM., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)

Background: The FDA approval of oncolytic herpes simplex-1 virus (oHSV) therapy underscores its therapeutic promise and safety as a cancer immunotherapy. Despite this promise, the current efficacy of oHSV is significantly limited to a small subset of patients largely due to the resistance in tumor and tumor microenvironment (TME)., Methods: RNA sequencing (RNA-Seq) was used to identify molecular targets of oHSV resistance. Intracranial human and murine glioma or breast cancer brain metastasis (BCBM) tumor-bearing mouse models were employed to elucidate the mechanism underlying oHSV therapy-induced resistance., Results: Transcriptome analysis identified IGF2 as one of the top-secreted proteins following oHSV treatment. Moreover, IGF2 expression was significantly upregulated in 10 out of 14 recurrent GBM patients after treatment with oHSV, rQNestin34.5v.2 (71.4%; P = .0020) (ClinicalTrials.gov, NCT03152318). Depletion of IGF2 substantially enhanced oHSV-mediated tumor cell killing in vitro and improved survival of mice bearing BCBM tumors in vivo. To mitigate the oHSV-induced IGF2 in the TME, we constructed a novel oHSV, oHSV-D11mt, secreting a modified IGF2R domain 11 (IGF2RD11mt) that acts as IGF2 decoy receptor. Selective blocking of IGF2 by IGF2RD11mt significantly increased cytotoxicity, reduced oHSV-induced neutrophils/PMN-MDSCs infiltration, and reduced secretion of immune suppressive/proangiogenic cytokines, while increased CD8 + cytotoxic T lymphocytes (CTLs) infiltration, leading to enhanced survival in GBM or BCBM tumor-bearing mice., Conclusions: This is the first study reporting that oHSV-induced secreted IGF2 exerts a critical role in resistance to oHSV therapy, which can be overcome by oHSV-D11mt as a promising therapeutic advance for enhanced viro-immunotherapy., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)

Background: Glioblastoma multiforme (GBM) is the most malignant brain tumor, with a poor prognosis and life expectancy of 14-16 months after diagnosis. The standard treatment for GBM consists of surgery, radiotherapy, and chemotherapy with temozolomide. Most patients become resistant to treatment after some time, and the tumor recurs. Therefore, there is a need for new drugs to manage GBM. Eslicarbazepine (ESL) is a well-known antiepileptic drug belonging to the dibenzazepine group with anticancer potentials. In this study, for the first time, we evaluated the potential effects of ESL on C6 cell growth, both in vitro and in vivo, and examined its molecular effects., Methods: To determine the effect of ESL on the c6 cell line, cell viability, proliferation, and migration were evaluated by MTT assay, colony formation, and wound healing assay. Also, apoptosis and cell cycle were examined by flow cytometry, qRT-PCR, and western blotting. In addition, an intracranial model in Wistar rats was used to investigate the effect of ESL in vivo, and the tumor size was measured using both Caliper and MRI., Results: The obtained results are extremely consistent and highly encouraging. C6 cell viability, proliferation, and migration were significantly suppressed in ESL-treated C6 cells (p < 0.001), as determined by cell-based assays. ESL treatment led to significant enhancement of apoptosis (p < 0.01), as determined by flow cytometry, and upregulation of genes involved in cell apoptosis, such as the Bax/Bcl2 ratio at RNA (p < 0.05) and protein levels (5.37-fold). Flow cytometric analysis of ESL-treated cells revealed G2/M phase cell cycle arrest. ESL-treated cells demonstrated 2.49-fold upregulation of p21 alongside, 0.22-fold downregulation of cyclin B1, and 0.34-fold downregulation of cyclin-dependent kinase-1 at the protein level. Administration of ESL (30 mg/kg) to male rats bearing C6 intracranial tumors also suppressed the tumor volume and weight (p < 0.01)., Conclusions: Based on these novel findings, ESL has the potential for further experimental and clinical studies in glioblastoma., (© 2024. The Author(s).)

Glioblastoma multiforme (GBM) is the most aggressive type of cancer in the brain and has an inferior prognosis because of the lack of suitable medicine, largely due to its tremendous invasion. GBM has selfish metabolic pathways to promote migration, invasion, and proliferation compared to normal cells. Among various metabolic pathways, NAD (nicotinamide adenine dinucleotide) is essential in generating ATP and is used as a resource for cancer cells. LbNOX (Lactobacillus brevis NADH oxidase) is an enzyme that can directly manipulate the NAD + /NADH ratio. In this study, we found that an increased NAD + /NADH ratio by LbNOX or mitoLbNOX reduced intracellular glutamate and calcium responses and reduced invasion capacity in GBM. However, the invasion was not affected in GBM by rotenone, an ETC (Electron Transport Chain) complex I inhibitor, or nicotinamide riboside, a NAD + precursor, suggesting that the crucial factor is the NAD + /NADH ratio rather than the absolute quantity of ATP or NAD + for the invasion of GBM. To develop a more accurate and effective GBM treatment, our findings highlight the importance of developing a new medicine that targets the regulation of the NAD + /NADH ratio, given the current lack of effective treatment options for this brain cancer., (© 2024. The Author(s).)

Background: Glioblastoma (GBM) is an immunosuppressive, universally lethal cancer driven by glioblastoma stem cells (GSCs). The interplay between GSCs and immunosuppressive microglia plays crucial roles in promoting the malignant growth of GBM; however, the molecular mechanisms underlying this crosstalk are unclear. This study aimed to investigate the role of POSTN in maintaining GSCs and the immunosuppressive phenotype of microglia., Methods: The expression of POSTN in GBM was identified via immunohistochemistry, quantitative real-time PCR, and immunoblotting. Tumorsphere formation assay, Cell Counting Kit-8 assay and immunofluorescence were used to determine the key role of POSTN in GSC maintenance. ChIP-seq and ChIP-PCR were conducted to confirm the binding sequences of β-catenin in the promoter region of FOSL1. Transwell migration assays, developmental and functional analyses of CD4 + T cells, CFSE staining and analysis, enzyme-linked immunosorbent assays and apoptosis detection tests were used to determine the key role of POSTN in maintaining the immunosuppressive phenotype of microglia and thereby promoting the immunosuppressive tumor microenvironment. Furthermore, the effects of POSTN on GSC maintenance and the immunosuppressive phenotype of microglia were investigated in a patient-derived xenograft model and orthotopic glioma mouse model, respectively., Results: Our findings revealed that POSTN secreted from GSCs promotes GSC self-renewal and tumor growth via activation of the αVβ3/PI3K/AKT/β-catenin/FOSL1 pathway. In addition to its intrinsic effects on GSCs, POSTN can recruit microglia and upregulate CD70 expression in microglia through the αVβ3/PI3K/AKT/NFκB pathway, which in turn promotes Treg development and functionality and supports the formation of an immunosuppressive tumor microenvironment. In both in vitro models and orthotopic mouse models of GBM, POSTN depletion disrupted GSC maintenance, decreased the recruitment of immunosuppressive microglia and suppressed GBM growth., Conclusion: Our findings reveal that POSTN plays critical roles in maintaining GSCs and the immunosuppressive phenotype of microglia and provide a new therapeutic target for treating GBM., (© 2024. The Author(s).)

Small cell lung cancer (SCLC) is an epithelial neuroendocrine form of lung cancer for which survival rates remain dismal and new therapeutic approaches are greatly needed. Key biological features of SCLC tumors include fast growth and widespread metastasis, as well as rapid resistance to treatment. Similar to pulmonary neuroendocrine cells, SCLC cells have traits of both hormone-producing cells and neurons. In this study, we specifically discuss the neuronal features of SCLC. We consider how neuronal G protein-coupled receptors and other neuronal molecules on the surface of SCLC cells can contribute to the growth of SCLC tumors and serve as therapeutic targets in SCLC. We also review recent evidence for the role of neuronal programs expressed by SCLC cells in the fast proliferation, migration, and metastasis of these cells. We further highlight how these neuronal programs may be particularly relevant for the development of brain metastases and how they can assist SCLC cells to functionally interact with neurons and astrocytes. A greater understanding of the molecular and cellular neuronal features of SCLC is likely to uncover new vulnerabilities in SCLC cells, which may help develop novel therapeutic approaches. More generally, the epithelial-to-neuronal transition observed during tumor progression in SCLC and other cancer types can contribute significantly to tumor development and response to therapy., (©2024 American Association for Cancer Research.)

High-grade gliomas (HGG) are deadly diseases for both adult and pediatric patients. Recently, it has been shown that neuronal activity promotes the progression of multiple subgroups of HGG. However, epigenetic mechanisms that govern this process remain elusive. Here we report that the chromatin remodeler chromodomain helicase DNA-binding protein 2 (CHD2) regulates neuron-glioma interactions in diffuse midline glioma (DMG) characterized by onco-histone H3.1K27M. Depletion of CHD2 in H3.1K27M DMG cells compromises cell viability and neuron-to-glioma synaptic connections in vitro, neuron-induced proliferation of H3.1K27M DMG cells in vitro and in vivo, activity-dependent calcium transients in vivo, and extends the survival of H3.1K27M DMG-bearing mice. Mechanistically, CHD2 coordinates with the transcription factor FOSL1 to control the expression of axon-guidance and synaptic genes in H3.1K27M DMG cells. Together, our study reveals a mechanism whereby CHD2 controls the intrinsic gene program of the H3.1K27M DMG subtype, which in turn regulates the tumor growth-promoting interactions of glioma cells with neurons. Significance: Neurons drive the proliferation and invasion of glioma cells. Here we show that chromatin remodeler chromodomain helicase DNA-binding protein 2 controls the epigenome and expression of axon-guidance and synaptic genes, thereby promoting neuron-induced proliferation of H3.1K27M diffuse midline glioma and the pathogenesis of this deadly disease., (©2024 American Association for Cancer Research.)

Glioblastoma (GBM) is amongst the deadliest types of cancers, with no resolutive cure currently available. GBM cell proliferation in the patient's brain is a complex phenomenon controlled by multiple mechanisms. The aim of this study was to determine whether the ionic fluxes controlling cell duplication could represent a target for GBM therapy. In this work, we combined multi-channel Ca2+ and Cl- imaging, optical tweezers, electrophysiology, and immunohistochemistry to describe the role of ion fluxes in mediating the cell volume changes that accompany mitosis of U87 GBM cells. We identified three main steps: (i) in round GBM cells undergoing mitosis, during the transition from anaphase to telophase and cytokinesis, large Ca2+ flares occur, reaching values of 0.5 to 1 μmol/L; (ii) these Ca2+ flares activate Ca2+-dependent Cl- channels, allowing the entry of Cl- ions; and (iii) to maintain osmotic balance, GBM cells swell to complete mitosis. This sequence of steps was validated by electrophysiological experiments showing that Cl- channels are activated either directly or indirectly by Ca2+, and by additional live-cell imaging experiments. Cl- channel blockers with different molecular structures, such as niflumic acid and carbenoxolone, blocked GBM replication by arresting GBM cells in a round configuration. These results describe the central role of Ca2+ flares and Cl- fluxes during mitosis and show that inhibition of Ca2+-activated Cl- channels blocks GBM replication, opening the way to new approaches for the clinical treatment of GBM. Implications: Our work identifies ionic fluxes occurring during cell division as targets for devising novel therapies for glioblastoma treatment., (©2024 American Association for Cancer Research.)

Glioblastoma (GBM) is the most common malignant primary brain cancer that, despite recent advances in the understanding of its pathogenesis, remains incurable. GBM contains a subpopulation of cells with stem cell-like properties called cancer stem cells (CSCs). Several studies have demonstrated that CSCs are resistant to conventional chemotherapy and radiation thus representing important targets for novel anti-cancer therapies. Proton sensing receptors expressed by CSCs could represent important factors involved in the adaptation of tumours to the extracellular environment. Accordingly, the expression of acid-sensing ion channels (ASICs), proton-gated sodium channels mainly expressed in the neurons of peripheral (PNS) and central nervous system (CNS), has been demonstrated in several tumours and linked to an increase in cell migration and proliferation. In this paper we report that the ASIC3 isoform, usually absent in the CNS and present in the PNS, is enriched in human GBM CSCs while poorly expressed in the healthy human brain. We propose here a novel therapeutic strategy based on the pharmacological activation of ASIC3, which induces a significant GBM CSCs damage while being non-toxic for neurons. This approach might offer a promising and appealing new translational pathway for the treatment of glioblastoma., (© 2024. The Author(s).)

This study examined to evaluate the predictive value of a nomogram with Ki-67 in overall and disease-free survival in glioma patients, a total of 76 patients diagnosed with glioma by pathology in Tengzhou Central People's Hospital were enrolled. The baseline data and follow ups were retrospectively collected from medical records. The associations between Ki-67 and survival status were examined using log-rank test, univariate and multivariate Cox proportional hazard regression models. Calibrations were performed to validate the established nomograms. Ki-67 negative group showed of a longer OS survival time and a longer PFS survival time with log-rank test (x 2  = 16.101, P < 0.001 and x 2  = 16.961, P < 0.001). Age older than 50 years (HR = 2.074, 95% CI 1.097-3.923), abnormal treatment (HR = 2.932, 95% CI 1.343-6.403) and Ki-67 positive (HR = 2.722, 95% CI 1.097-6.755) were the independent predictive factors of death. High grade pathology (HR = 2.453, 95% CI 1.010-5.956) and Ki-67 positive (HR = 2.200, 95% CI 1.043-4.639) were the independent predictive factors of recurrence. The C-index for the nomogram of OS and PFS were 0.745 and 0.723, respectively. The calibration results showed that the nomogram could predict the overall and disease-free 1-year survival of glioma patients. In conclusion, the nomograms with Ki-67 as independent risk factor for OS and PFS could provide clinical consultation in the treatment and follow-up of malignant glioma., (© 2024. The Author(s).)

Disrupted lipid metabolism is a characteristic of gliomas. This study utilizes an ultrastructural approach to characterize the prevalence and distribution of lipids within gliomas. This study made use of tissue from IDH1 wild type (IDH1-wt) glioblastoma ( n  = 18) and IDH1 mutant (IDH1-mt) astrocytoma ( n  = 12) tumors. We uncover a prevalent and intriguing surplus of lipids. The bulk of the lipids manifested as sizable cytoplasmic inclusions and extracellular deposits in the tumor microenvironment (TME); in some tumors the lipids were stored in the classical membraneless spheroidal lipid droplets (LDs). Frequently, lipids accumulated inside mitochondria, suggesting possible dysfunction of the beta-oxidation pathway. Additionally, the tumor vasculature have lipid deposits in their lumen and vessel walls; this lipid could have shifted in from the tumor microenvironment or have been produced by the vessel-invading tumor cells. Lipid excess in gliomas stems from disrupted beta-oxidation and dysfunctional oxidative phosphorylation pathways. The implications of this lipid-driven environment include structural support for the tumor cells and protection against immune responses, non-lipophilic drugs, and free radicals.

Summary: Imagine if we could simultaneously predict spatial protein expression in tissues from their routine Hematoxylin and Eosin (H&E) stained images, and create tissue images given protein expression profiles thus enabling virtual simulations of how protein expression alterations impact histology in complex diseases like cancer. Such an approach could lead to more informed diagnostic and therapeutic decisions for precision medicine at lower costs and shorter turnaround times, more detailed insights into underlying disease pathology as well as improvement in predictive and generative performance. In this study, we investigate the intricate correlation between protein expressions obtained from Hyperion mass cytometry and histopathological microstructures in conventional H&E stained glioblastoma (GBM) samples, unveiling morphological patterns and cellular-level spatial alterations associated with protein expression changes. To model these complex relationships, we propose a novel generative-predictive framework called Ouroboros for producing H&E images from protein expressions and simultaneously predicting protein expressions from H&E images. Our comprehensive sample-independent validation over 9920 tissue spots from 4 GBM samples encompassing visual image analysis, quantitative analysis, subspace alignment and perturbation experiments shows that the proposed generative-predictive approach offers significant improvements in predicting protein expression from images in comparison to baseline methods as well as accurate generation of virtual GBM sample images. This proof of concept study can contribute to advancing our understanding of histological responses to protein expression perturbations and lays the foundations for further developments in this area., Availability and Implementation: Implementation and associated data for the proposed approach are available at the URL: https://github.com/Srijay/Ouroboros., (© The Author(s) 2024. Published by Oxford University Press.)

Objective: The E3 ubiquitin ligase is well recognized as a significant contributor to glioblastoma (GBM) progression and has promise as a prospective therapeutic target. This study explores the contribution of E3 ubiquitin ligase RNF122 in the GBM progression and the related molecular mechanisms., Methods: RNF122 expression levels were evaluated using qRT-PCR, WB, and IHC, while functional assays besides animal experiments were used to assess RNF122's effect on GBM progression. We also tested the RNF122 impact on JAK2/STAT3/c-Myc signaling using WB., Results: RNF122 was upregulated in GBM and correlated to the advanced stage and poor clinical outcomes, representing an independent prognostic factor. Based on functional assays, RNF122 promotes GBM growth and cell cycle, which was validated further in subsequent analyses by JAK2/STAT3/c-Myc pathway activation. Moreover, JAK2/STAT3 signaling pathway inhibitor WP1066 can weaken the effect of overexpression RNF122 on promoting GBM progression., Conclusion: Our results revealed that RNF122 caused an aggressive phenotype to GBM and was a poor prognosticator; thus, targeting RNF122 may be effectual in GBM treatment., (© 2024 The Author(s). CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)

Background/aim: Glioblastoma is the most aggressive form of brain tumor and has a dismal prognosis; therefore, novel therapeutic approaches based on the mechanisms underlying its aggressive nature are urgently required. A growing body of evidence suggests that neurotransmitters play a key role in modulating the biology of glioblastoma; however, the role of melanocortins remains unclear., Materials and Methods: The effects of bremelanotide, a melanocortin receptor agonist, alone or in combination with chemotherapeutic agents, on survivin expression and cell viability were investigated in human glioblastoma cell lines., Results: Bremelanotide reduced survivin expression and induced cell death in glioblastoma cells at concentrations that were not toxic to normal human cells, and both of these effects were canceled in the presence of an antagonist of melanocortin receptors 3 and 4. Bremelanotide-induced cell death was prevented by the forced over-expression of survivin in glioblastoma cells, suggesting that bremelanotide induces glioblastoma cell death by inhibiting the expression of survivin. Bremelanotide also promoted cell death induced by chemotherapeutic agents, such as temozolomide and osimertinib., Conclusion: The present results identified melanocortin receptors 3 and 4 as novel and viable therapeutic targets for glioblastoma. Activation of these receptors by bremelanotide may inhibit the expression of survivin, thereby sensitizing glioblastoma cells to cell death., (Copyright © 2024 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Purpose: 18 F-FDG PET captures the relationship between glucose metabolism and synaptic activity, allowing for modeling brain function through metabolic connectivity. We investigated tumor-induced modifications of brain metabolic connectivity., Patients and Methods: Forty-three patients with left hemispheric tumors and 18 F-FDG PET/MRI were retrospectively recruited. We included 37 healthy controls (HCs) from the database CERMEP-IDB-MRXFDG. We analyzed the whole brain and right versus left hemispheres connectivity in patients and HC, frontal versus temporal tumors, active tumors versus radiation necrosis, and patients with high Karnofsky performance score (KPS = 100) versus low KPS (KPS < 70). Results were compared with 2-sided t test ( P < 0.05)., Results: Twenty high-grade glioma, 4 low-grade glioma, and 19 metastases were included. The patients' whole-brain network displayed lower connectivity metrics compared with HC ( P < 0.001), except assortativity and betweenness centrality ( P = 0.001). The patients' left hemispheres showed decreased similarity, and lower connectivity metrics compared with the right ( P < 0.01), with the exception of betweenness centrality ( P = 0.002). HC did not show significant hemispheric differences. Frontal tumors showed higher connectivity metrics ( P < 0.001) than temporal tumors, but lower betweenness centrality ( P = 4.5 -7 ). Patients with high KPS showed higher distance local efficiency ( P = 0.01), rich club coefficient ( P = 0.0048), clustering coefficient ( P = 0.00032), betweenness centrality ( P = 0.008), and similarity ( P = 0.0027) compared with low KPS. Patients with active tumor(s) (14/43) demonstrated significantly lower connectivity metrics compared with necroses., Conclusions: Tumors cause reorganization of metabolic brain networks, characterized by formation of new connections and decreased centrality. Patients with frontal tumors retained a more efficient, centralized, and segregated network than patients with temporal tumors. Stronger metabolic connectivity was associated with higher KPS., Competing Interests: Conflicts of interest and sources of funding: Andrei Holodny is the Owner/President of fMRI Consultants, LLC, a purely educational entity. This study was supported by NIH/NCI Cancer Center Support Grant P30 CA008748 (PI: Vickers), NIH/NIBIB R01 EB022720 (PIs: Makse and Holodny), and NIH/NCI R21 CA220144 (PIs: Holodny and Peck)., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Despite enormous efforts being invested in the development of novel therapies for brain malignancies, there remains a dire need for effective treatments, particularly for pediatric glioblastomas. Their poor prognosis has been attributed to the fact that conventional therapies target tumoral cells, but not glioblastoma stem cells (GSCs). GSCs are characterized by self-renewal, tumorigenicity, poor differentiation, and resistance to therapy. These characteristics represent the fundamental tools needed to recapitulate the tumor and result in a relapse. The mechanisms by which GSCs alter metabolic cues and escape elimination by immune cells are discussed in this article, along with potential strategies to harness effector immune cells against GSCs. As cellular immunotherapy is making significant advances in a variety of cancers, leveraging this underexplored reservoir may result in significant improvements in the treatment options for brain malignancies., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Glutamate chemical exchange saturation transfer (GluCEST) is a non-invasive CEST imaging technique for detecting glutamate levels in tissues. We aimed to investigate the reproducibility of the 5T GluCEST technique in healthy volunteers and preliminarily explore its potential clinical application in patients with brain tumors., Methods: Ten volunteers (4 males, mean age 29 years) underwent three 5T GluCEST imaging scans. The reproducibility of the three imaging GluCEST measurements was assessed using one-way repeated measures analysis of variance (ANOVA), generalized estimating equations, and linear mixed models. Twenty-eight patients with brain tumors (10 males, mean age 54 years) underwent a single GluCEST scan preoperatively, and t-tests were used to compare the differences in GluCEST values between different brain tumors. In addition, the diagnostic accuracy of GluCEST values in differentiating brain tumors was assessed using the receiver work characteristics (ROC) curve., Results: The coefficients of variation of GluCEST values in healthy volunteers were less than 5% for intra-day, inter-day, and within-subjects and less than 10% for between-subjects. High-grade gliomas (HGG) had higher GluCEST values compared to low-grade gliomas (LGG) (P < 0.001). In addition, cerebellopontine angle (CPA) meningiomas had higher GluCEST values than acoustic neuromas (P < 0.001). The area under the curve (AUC) of the GluCEST value for differentiating CPA meningioma from acoustic neuroma was 0.93., Conclusion: 5T GluCEST images are highly reproducible in healthy brains. In addition, the 5T GluCEST technique has potential clinical applications in differentiating LGG from HGG and CPA meningiomas from acoustic neuromas., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: The unsatisfactory efficacy of PD-L1 antibodies in glioblastoma (GBM) is largely due to the temporal and spatial heterogeneity of PD-L1 expression. Molecular imaging can enhance understanding of the tumor immune microenvironment and guide immunotherapy. However, highly sensitive imaging agents capable of effectively visualizing PD-L1 heterogeneity are limited. This study introduces a novel PET tracer, offering improved imaging of PD-L1 heterogeneity in GBM xenografts, with a comparative analysis to [ 18 F]AlF-NOTA-WL12., Methods: [ 18 F]AlF-NOTA-PCP2 was synthesized with high purity and its affinity for PD-L1 was characterized using surface plasmon resonance (SPR) and cell binding assays. Its specificity for PD-L1 was evaluated both in vitro using various cell lines and in vivo with GBM xenograft models in NOD/SCID mice. PET/CT imaging was conducted to evaluate the tracer's biodistribution, pharmacokinetics, and ability to quantify tumoral spatial heterogeneity of PD-L1 expression. A focused comparative analysis between [ 18 F]AlF-NOTA-PCP2 and [ 18 F]AlF-NOTA-WL12 was conducted, examining binding affinity, biodistribution, pharmacokinetics, and imaging effectiveness in GBM xenografts. Additionally, human radiation dosimetry estimates compared the safety profiles of both tracers., Results: [ 18 F]AlF-NOTA-PCP2 demonstrated high radiochemical purity (> 95%) and a strong affinity for PD-L1, comparable to [ 18 F]AlF-NOTA-WL12. In vitro and in vivo studies confirmed its specificity for PD-L1, with increased uptake in PD-L1 expressing cells and tumors. Toxicological profiles indicated no significant abnormalities in serum biochemical indicators or major organ tissues. MicroPET/CT imaging showed [ 18 F]AlF-NOTA-PCP2's effectiveness in visualizing PD-L1 expression levels and spatial heterogeneity in GBM xenografts. Comparative studies revealed [ 18 F]AlF-NOTA-PCP2's improved pharmacokinetic properties, including higher tumor-to-blood ratios and lower nonspecific liver uptake, as well as reduced radiation exposure compared to [ 18 F]AlF-NOTA-WL12., Conclusion: [ 18 F]AlF-NOTA-PCP2 distinguishes itself as an exceptionally sensitive PET/CT tracer, adept at non-invasively and accurately quantifying PD-L1 expression and its spatial heterogeneity in tumors, especially in GBM. Its favorable pharmacokinetic properties, safety profile, and high affinity for PD-L1 highlight its potential for enhancing the precision of cancer immunotherapy and guiding individualized treatment strategies. While promising, its clinical translation, especially in brain imaging, necessitates further validation in clinical trials., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background/aim: Glioblastomas (GBM) are infiltrative malignant brain tumors which mostly recur within a year's time following surgical resection and chemo-radiation therapy. Studies on glioblastoma cells following radio-chemotherapy, have been demonstrated to induce trans-differentiation, cellular plasticity, activation of DNA damage response and stemness. As glioblastomas are heterogenous tumors that develop treatment resistance and plasticity, we investigated if there exist genome-wide DNA methylation changes in recurrent tumors., Materials and Methods: Utilizing genome-wide DNA methylation arrays, we compared the DNA methylation profile of 11 primary (first occurrence) tumors with 13 recurrent (relapsed) GBM, to delineate the contribution of epigenetic changes associated with therapy exposure, therapy resistance, and relapse of disease., Results: Our data revealed 1,224 hypermethylated- and 526 hypomethylated-probes in recurrent glioblastomas compared to primary disease. We found differential methylation of solute carrier and ion channel genes, interleukin receptor/ligand genes, tumor-suppressor genes and genes associated with metastasis. We functionally characterized one such hypomethylated-up-regulated gene, namely anthrax toxin receptor 1/tumor endothelial marker 8 (ANTXR1/TEM8), whose expression was validated to be significantly up-regulated in recurrent glioblastomas compared to primary tumors and confirmed by immunohistochemistry. Using overexpression and knockdown approaches, we showed that TEM8 induces proliferation, invasion, migration, and chemo-radioresistance in glioblastoma cells. Additionally, we demonstrated a novel mechanism of β-catenin stabilization and activation of the β-catenin transcriptional program due to TEM8 overexpression via a Src/PI3K/AKT/GSK3β/β-catenin pathway., Conclusion: We report genome-wide DNA methylation changes in recurrent GBM and suggest involvement of the TEM8 gene in GBM recurrence and progression., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Brain metastases account for more than 50 % of intracranial central nervous system tumors. The blood-brain barrier (BBB) is mainly composed of endothelial cells, which exhibit low endocytosis and high efflux pumps. Although they are connected by continuous tight junctions and serve as a protective insulation, the BBB does not prevent the development of brain metastases from non-small cell lung cancer (NSCLC). Improving understanding on the mechanisms underlying the development of brain metastasis and the differential molecular characteristics relative to the primary tumor are therefore key in the treatment of brain metastases. This study evaluated the differential expression of miR-522-3p in NSCLC and brain metastases using the Gene Expression Omnibus database. NSCLC brain metastasis model was constructed to screen for cell lines that demonstrated high potential for brain metastasis; We also observed differential expression of miRNA-522-3p in the paraffin-embedded specimens of non-small cell lung cancer and brain metastases from our hospital. The molecular biological functions of miRNA-522-3p were verified using 5-ethynyl-2'-deoxyuridine (EdU) proliferation assay and Transwell invasion assays. RNA-seq was employed to identify downstream target proteins, and the dual-luciferase reporter assay confirmed Tensin 1 (TNS1), a protein that links the actin cytoskeleton to the extracellular matrix, as the downstream regulatory target protein. In vitro blood-brain barrier models and co-culture models were constructed to further identify the role of miRNA-522-3p and TNS1; the expression of BBB-related proteins (ZO-1 and OLCN) was also identified. In vivo experiments were performed to verify the effects of miRNA-522-3p on the time and incidence of NSCLC brain metastasis. The results showed significantly high expression in GSE51666; consistent results were obtained in brain metastasis cells and paraffin samples. RNA-seq combined with miRNA target protein prediction demonstrated TNS1 to be directly downstream of miR-522-3p and to be associated with cell proliferation and invasion. By regulating ZO-1 and OCLN expression, mi-522-3p/TNS1 may increase tumor cell penetration through the BBB while decreasing its permeability. In vivo, miR-522-3p was further demonstrated to significantly promote the formation of brain metastases. miR-522-3p/TNS1 can affect BBB permeability and encourage the growth of brain metastases by modifying the BBB TJ proteins. This axis offers new therapeutic targets for the prevention of brain metastasis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Purpose: To investigate prognostic markers for H3 K27-altered diffuse midline gliomas (DMGs) in adults with clinical, qualitative and quantitative imaging phenotypes, including tumor oxygenation characteristics., Methods: Retrospective chart and imaging reviews were conducted on 32 adults with H3 K27-altered DMGs between 2017 and 2023. Clinical and qualitative imaging characteristics were analyzed. Quantitative imaging assessment was performed from the tumor mask via automatic segmentation to calculate normalized cerebral blood volume (nCBV), capillary transit time heterogeneity (CTH), oxygen extraction fraction (OEF), relative cerebral metabolic rate of oxygen (rCMRO 2 ), and mean ADC values. Leptomeningeal metastases (LM) was diagnosed with imaging. Cox analyses were conducted to determine predictors of overall survival (OS) in entire patients and a subgroup of patients with contrast-enhancing (CE) tumor., Results: The median patient age was 40.5 years (range 19.9-75.7), with an OS of 30.3 months (interquartile range 11.3-32.3). In entire patients, the presence of LM was the only independent predictor of OS (hazard ratio [HR] = 6.01, P = 0.009). In the subgroup of 23 (71.9%) patients with CE tumors, rCMRO 2 of CE tumor (HR = 1.08, P = 0.019) and the presence of LM (HR = 5.92, P = 0.043) were independent predictors of OS., Conclusion: The presence of LM was independently associated with poor prognosis in adult patients with H3 K27-altered DMG. In patients with CE tumors, higher rCMRO 2 of CE tumor, which may reflect higher metabolic activity in the tumor oxygenation microenvironment, may be a useful imaging biomarker to predict poor prognosis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Gliomas, the most common CNS (central nerve system) tumors, face poor survival due to severe chemoresistance exacerbated by hypoxia. However, studies on whether altered hypoxic conditions benefit for chemo-sensitivity and how gliomas react to increased oxygen stimulation are limited. In this study, we demonstrated that increased oxygen stimulation promotes glioma growth and chemoresistance. Mechanically, increased oxygen stimulation upregulates miR-1290 levels. miR-1290, in turn, downregulates PLCB1, while PLCB1 facilitates the proteasomal degradation of β-catenin and active-β-catenin by increasing the proportion of ubiquitinated β-catenin in a destruction complex-independent mechanism. This process inhibits PLCB1 expression, leads to the accumulation of active-β-catenin, boosting Wnt signaling through an independent mechanism and ultimately promoting chemoresistance in glioma cells. Pharmacological inhibition of Wnt by WNT974 could partially inhibit glioma volume growth and prolong the shortened survival caused by increased oxygen stimulation in a glioma-bearing mouse model. Moreover, PLCB1, a key molecule regulated by increased oxygen stimulation, shows promising predictive power in survival analysis and has great potential to be a biomarker for grading and prognosis in glioma patients. These results provide preliminary insights into clinical scenarios associated with altered hypoxic conditions in gliomas, and introduce a novel perspective on the role of the hypoxic microenvironment in glioma progression. Furthermore, the outcomes reveal the potential risks of utilizing hyperbaric oxygen treatment (HBOT) in glioma patients, particularly when considering HBOT as a standalone option to ameliorate neuro-dysfunctions or when combining HBOT with a single chemotherapy agent without radiotherapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Purpose: Magnetization transfer ratio asymmetry (MTRasym) analysis is used for chemical exchange saturation transfer (CEST) in patients with gliomas; however, this approach has limitations. CEST imaging using a multi-pool model (MPM) may allow a more detailed assessment of gliomas; however, its mechanism remains unknown. This study aimed to assess the relationship between CEST imaging by MPM, intravoxel incoherent motion (IVIM), and 11 C-methionine ( 11 C-MET) uptake on positron emission tomography/computed tomography (PET/CT) to clarify the clinical significance of CEST imaging using MPM in gliomas., Methods: This retrospective study included 17 patients with gliomas who underwent 11 C-MET PET/CT at our institution between January 2020 and January 2022. Two-dimensional axial CEST imaging was conducted using single-shot fast-spin echo acquisition at 3 T. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), f, MTRasym (3.5 ppm), parameters of MPM-based CEST imaging, and tumor-to-contralateral normal brain tissue (T/N) ratio were calculated using a region-of-interest analysis. Shapiro-Wilk test, weighted kappa coefficient, and Spearman's rank correlation coefficients were used for statistical analysis., Results: Significant correlations were found between APT&#95;T1 and T/N ratio (ρ = 0.87, p < 0.001), APT&#95;T2 and T/N ratio (ρ = 0.47, p < 0.05), MTRasym and T/N ratio (ρ = 0.55, p < 0.01), and T2/T1 and T/N ratio (ρ = -0.36, p < 0.05). Furthermore, significant correlations were observed between APT&#95;T1 and ADC (ρ = -0.67, p < 0.001), APT&#95;T1 and D (ρ = -0.70, p < 0.001), APT&#95;T2 and D* (ρ = -0.45, p < 0.05), and T2/T1 and D (ρ = 0.39, p < 0.05)., Conclusion: These preliminary findings indicate that MPM-based CEST imaging parameters correlate with IVIM and 11 C-MET uptake on PET/CT in patients with gliomas. In particular, the new parameter APT&#95;T1 correlated more strongly with 11 C-MET uptake compared to the traditional CEST parameter MTRasym., Competing Interests: Declaration of competing interest Mitsuharu Miyoshi is an employee of GE HealthCare. The other authors have no conflicts of interest., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: PreOperative radiotherapy (RT) is commonly used in the treatment of brain metastasis and different cancer types but has never been used in primary glioblastoma (GBM). Here, we aim to establish, describe, and validate the use of PreOperative RT for the treatment of GBM in a preclinical model., Methods: Rat brains were locally irradiated with 30-Gy, hypofractionated in five doses 2 weeks before or after the resection of intracranial GBM. Kaplan-Meier analysis determined survival. Hematoxylin-eosin staining was performed, and nuclei size and p21 senescence marker were measured in both resected and recurrent rodent tumors. Immunohistochemistry assessed microglia/macrophage markers, and RNAseq analyzed gene expression changes in recurrent tumors. Akoya Multiplex Staining on two human patients from our ongoing Phase I/IIa trial served as proof of principle., Results: PreOperative RT group median survival was significantly higher than PostOperative RT (p < 0.05). Radiation enlarged cytoplasm and nuclei in PreOperative RT resected tumors (p < 0.001) and induced senescence in PostOperative RT recurrent tumors (p < 0.05). Gene Set Enrichment Analysis (GSEA) suggested a more proliferative profile in PreOperative RT group. PreOperative RT showed lower macrophage/microglia recruitment in recurrent tumors (p < 0.01) compared to PostOperative RT. Akoya Multiplex results indicated TGF-ß accumulation in the cytoplasm of TAMs and CD4 + lymphocyte predominance in PostOperative group., Conclusions: This is the first preclinical study showing feasibility and longer overall survival using neoadjuvant radiotherapy before GBM resection in a mammalian model. This suggests strong superiority for new clinical radiation strategies. Further studies and trials are required to confirm our results., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Bisphenol S (BPS), an alternative to bisphenol A (BPA), exerts proliferative effects similar to those of BPA. BPS is a representative endocrine disruptor associated with cancer progression. However, the mechanisms underlying BPS-induced glioblastoma progression are not fully understood. To investigate the effects of BPS on glioblastoma, U-87 MG cancer cell lines were exposed to BPS. The study focused on analyzing the proliferation and migration of U-87 MG cells. Furthermore, the involvement of the enhancer of the zeste homolog 2 (EZH2)-mediated phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of the rapamycin (mTOR) pathway was examined. Pharmacological approaches were employed to inhibit EZH2 activity and observe its effects on BPS-induced changes. The results indicated that BPS promoted the proliferation and migration of U-87 MG cells at a concentration of 0.1 µM. These changes appeared to be linked to the activation of the EZH2-mediated PI3K/AKT/mTOR pathway. Moreover, inhibiting EZH2 activity using pharmacological approaches restored the BPS-mediated induction of proliferation and migration. In conclusion, the results of this study indicated that BPS induces glioblastoma progression through EZH2 upregulation. Therefore, targeting the EZH2-mediated PI3K/AKT/mTOR pathway could be considered a potential therapeutic strategy for the treatment of glioblastoma., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Translocator protein (TSPO) is involved in several cellular mechanisms such as steroidogenesis, immunomodulation, cell proliferation and differentiation. Overexpressed in several neurodegenerative diseases and brain cancer, TSPO radioligands have been developed over the last 20 years in positron emission tomography (PET) imaging. Recently, TSPO radioligands have extended beyond their initial application due to their specific binding to activated macrophages, making them a compelling biomarker for deciphering the intricacies of the tumor microenvironment (TME). In this review, we synthesized recent progress from the evaluation of TSPO-specific PET tracers in various peripheral tumor models and highlighted the hurdles and limitations associated with heterogeneous uptake in healthy tissue and tumor regions to achieve the clinical development of such a radiotracer., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Malignant gliomas are the most prevalent primary malignant cerebral tumors. Preoperative imaging plays an important role, and the prognosis is closely related to surgical resection and histomolecular aspects. Our goal was to correlate Ki67 indexes with tumoral volumetry in semiautomatic segmentation on preoperative magnetic resonance images and residual fluorescence in a 5-ALA-assisted resection cohort., Methods: We included 86 IDH-wildtype glioblastoma patients with complete preoperative imaging submitted to 5-ALA assisted resections. Clinical, surgical, and histomolecular findings were also obtained. Preoperative magnetic resonance studies were preprocessed and segmented semiautomatically on Visualization and Analysis for whole tumor (WT) on 3D FLAIR, enhancing tumor (ET), and necrotic core on 3D postgadolinium T1. We performed a linear regression analysis for Ki67 and a multivariate analysis for surgical outcomes., Results: Higher Ki-67 indexes correlated positively with higher WT (P = 0.048) and ET (P = 0.002). Lower Ki67 correlated with 5-ALA free margins (P = 0.045). WT and ET volumes correlated with the extent of resection (EOR; P = 0.002 and 0.002, respectively). Eloquence did not impact EOR (P = 0.14)., Conclusions: There is a correlation between Ki67, the metabolically active tumoral volumes (WT and ET), and 5-ALA residual fluorescence. Methodological inconsistencies are probably responsible for contradictory literature findings, and further prospective studies are needed to validate and reproduce these findings., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Glioblastoma (GBM) is a highly angiogenic malignancy of the central nervous system that resists standard antiangiogenic therapy, in part because of an alternative process to angiogenesis termed vasculogenic mimicry. Intricately linked to GBM, dysregulation of the Hippo signaling pathway leads to overexpression of YAP/TEAD and several downstream effectors involved in therapy resistance. Little is known about whether vasculogenic mimicry and the Hippo pathway intersect in the GBM chemoresistance phenotype. This study seeks to investigate the expression patterns of Hippo pathway regulators within clinically annotated GBM samples, examining their involvement in vitro regarding vasculogenic mimicry. In addition, it aims to assess the potential for pharmacological targeting of this pathway. In-silico analysis of the Hippo signaling members YAP1 , TEAD1 , AXL , NF2 , CTGF , and CYR61 transcript levels in low-grade GBM and GBM tumor tissues was done by Gene Expression Profiling Interactive Analysis. Gene expression was analyzed by real-time quantitative PCR from human U87, U118, U138, and U251 brain cancer cell lines and in clinically annotated brain tumor cDNA arrays. Transient gene silencing was performed with specific small interfering RNA. Vasculogenic mimicry was assessed using a Cultrex matrix, and three-dimensional capillary-like structures were analyzed with Wimasis. CYR61 and CTGF transcript levels were elevated in GBM tissues and were further induced when in-vitro vasculogenic mimicry was assessed. Silencing of CYR61 and CTGF , or treatment with a small-molecule TEAD inhibitor LM98 derived from flufenamic acid, inhibited vasculogenic mimicry. Silencing of SNAI1 and FOXC2 also altered vasculogenic mimicry and reduced CYR61 / CTGF levels. Pharmacological targeting of the Hippo pathway inhibits in-vitro vasculogenic mimicry. Unraveling the connections between the Hippo pathway and vasculogenic mimicry may pave the way for innovative therapeutic strategies., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Glioma is a serious primary malignant tumor of the human central nervous system with a poor prognosis and a high recurrence rate; however, inhibition of immune checkpoints can greatly improve the survival rate of patients. The purpose of this study was to investigate the regulation of PD-L1 by cordycepin and the mechanism of its anti-tumor action. The results of previous studies indicate that cordycepin has good anti-proliferative and anti-migratory activities and can induce apoptosis in U251 and T98G cells in vitro. Here, transcriptome sequencing showed that cordycepin may exert anti-tumor effects through the NOD-like receptor signaling pathway. Further intervention with BMS-1, a small molecule inhibitor of PD-L1, was used to explore whether inhibition of PD-L1 affected the regulation of the NOD-like receptor signaling pathway by cordycepin. Mechanistically, on the one hand, cordycepin regulated the expression of NFKB1 and STAT1 through the NOD-like receptor signaling pathway, thereby inhibiting the expression of PD-L1. In addition, inhibition of PD-L1 enhanced the regulation by cordycepin of the NOD-like receptor signaling pathway. On the other hand, cordycepin directly upregulated expression of STAT1 and downregulated that of PD-L1. In vivo studies further showed that cordycepin could downregulate expression of PD-L1 and NFKB1 and upregulate that of STAT1 in glioma xenograft tumor tissues, consistent with the results of in vitro studies. The results suggest that cordycepin may down-regulate the expression of PD-L1 through NOD-like receptor signaling pathway and NFKB signaling pathway, thereby inhibiting the immune escape of glioma, and can be developed as a PD-L1 inhibitor. Our results therefore provide a theoretical foundation for the use of cordycepin in treatment of glioma and enrich our understanding of its pharmacological mechanism., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Pediatric low grade brain tumors and neurodevelopmental disorders share proteins, signaling pathways, and networks. They also share germline mutations and an impaired prenatal differentiation origin. They may differ in the timing of the events and proliferation. We suggest that their pivotal distinct, albeit partially overlapping, outcomes relate to the cell states, which depend on their spatial location, and timing of gene expression during brain development. These attributes are crucial as the brain develops sequentially, and single-cell spatial organization influences cell state, thus function. Our underlying premise is that the root cause in neurodevelopmental disorders and pediatric tumors is impaired prenatal differentiation. Data related to pediatric brain tumors, neurodevelopmental disorders, brain cell (sub)types, locations, and timing of expression in the developing brain are scant. However, emerging single cell technologies, including transcriptomic, spatial biology, spatial high-resolution imaging performed over the brain developmental time, could be transformational in deciphering brain pathologies thereby pharmacology., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Advancements in metastatic breast cancer (BC) treatment have enhanced overall survival (OS), leading to increased rates of brain metastases (BM). This study analyzes the association between microsurgical tumor reduction and OS in patients with BCBM, considering tumor molecular subtypes and perioperative treatment approaches., Methods: Retrospective analysis of surgically treated patients with BCBM from two tertiary brain tumor Swiss centers. The association of extent of resection (EOR), gross-total resection (GTR) achievement, and postoperative residual tumor volume (RV) with OS and intracranial progression-free survival (IC-PFS) was evaluated using Cox proportional hazard model., Results: 101 patients were included in the final analysis, most patients (38%) exhibited HER2-/HR + BC molecular subtype, followed by HER2 + /HR + (25%), HER2-/HR- (21%), and HER2 + /HR- subtypes (13%). The majority received postoperative systemic treatment (75%) and radiotherapy (84%). Median OS and intracranial PFS were 22 and 8 months, respectively. The mean pre-surgery intracranial tumor volume was 26 cm 3 , reduced to 3 cm 3 post-surgery. EOR, GTR achievement and RV were not significantly associated with OS or IC-PFS, but higher EOR and lower RV correlated with extended OS in patients without extracranial metastases. HER2-positive tumor status was associated with longer OS, extracranial metastases at BM diagnosis and symptomatic lesions with shorter OS and IC-PFS., Conclusions: Our study found that BC molecular subtypes, extracranial disease status, and BM-related symptoms were associated with OS in surgically treated patients with BCBM. Additionally, while extensive resection to minimize residual tumor volume did not significantly affect OS across the entire cohort, it appeared beneficial for patients without extracranial metastases., (© 2024. The Author(s).)

Objectives: This study aimed to explore the expression, clinical significance, and functional mechanism of FYN in lower-grade gliomas (LGG)., Methods: The mRNA and protein expression of FYN in LGG tissues were detected using databases including OncoLnc, GEPIA, and Human protein atlas (HPA). The UCSC Xena browser, TIMER, STRING and Metascape databases were used to investigate Kaplan-Meier survival curves, correlations between FYN expression and various types of immune cell infiltration, protein interaction network and possible functional mechanism., Results: FYN expression in LGG, IDH mutation or 1p19q co-deletion subgroup was significantly higher than in corresponding control groups ( p  < 0.05). Patients with higher FYN expression had longer overall survival ( p  < 0.05). Male or no 1p19q co-deletion groups with higher FYN expression also had longer overall survival ( p  < 0.05). FYN expression had close correlation with infiltrating levels of cell purity, CD4+T cells, macrophages, and CD8+T cells ( p  < 0.05). Protein interaction network result showed correlation among FYN, SH2D1A, LCK, CAV1, SRC, CBL and PTK2. Functional enrichment analysis revealed that FYN and its related genes mainly participated in bacterial invasion of epithelial cells and natural killer cell mediated cytotoxicity. Peptidyl-tyrosine phosphorylation, negative regulation of anoikis, immune effector process, transmembrane receptor protein tyrosine kinase signaling pathway, epidermal growth factor receptor signaling pathway, and negative regulation of protein modification process may be the critical biological process., Conclusions: FYN is up-expressed in LGG and related to its good prognosis. It participated in tumor pathophysiological processes and may be a therapeutic target for LGG.

Current treatment for Glioblastoma Multiforme (GBM) is not efficient due to its aggressive nature, tendency to infiltrate surrounding brain tissue, and chemotherapy resistance. Tetrahydroquinoline scaffolds are emerging as a new class of drug for treating many human cancers including GBM. This study investigates the cytotoxicity effect of eight novel derivatives of 2-((3,4-dihydroquinolin-1(2H)-yl)(aryl)methyl)phenol, containing substitute 1 with reduced dihydroquinoline fused with cyclohexene ring and substitute 2 with phenyl and methyl group. The 4-position of the aryl ring was determinant for the desired cytotoxicity, and out of the 8 synthesized compounds, the 4-trifluoromethyl substituted derivative (4ag) exhibited the most anti-GBM potential effect compared to the standard chemotherapeutic agent, temozolomide (TMZ), with IC 50 values of 38.3 μM and 40.6 μM in SNB19 and LN229 cell lines, respectively. Our results demonstrated that 4ag triggers apoptosis through the activation of Caspase-3/7. In addition, 4ag induced intracellular reactive oxygen species (iROS) which in turn elevated mitochondrial ROS (mtROS) and causes the disruption of the mitochondrial membrane potential (Δψmt) in both GBM cells. This compound also exhibited anti-migratory properties over the time in both the cell lines. Overall, these findings suggest that tetrahydroquinoline derivative, 4ag could lead to the development of a new drug for treating GBM., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Glioblastoma (GB) is one of the most lethal types of neoplasms with unique anatomic, physiologic, and pathologic features that usually persist after exposure to standard therapeutic modalities. It is biologically aggressive, and the existence of the blood-brain barrier (BBB) limits the efficacy of standard therapies. In this work, we hypothesize the potential of surface-functionalized ultra-small nanostructured lipid carriers (usNLCs) with charge-switchable cell-penetrating peptides (CPPs) to overcome this biological barrier and improve targeted delivery to brain tumor tissues. The big question is: what is the potential of CPPs in directing nanoparticles toward brain tumor tissue? To answer this question, the usNLCs were functionalized with distinct biomolecules [five CPPs, c(RGDfK) and transferrin, Tf] through electrostatic interaction and its ability as a targeting approach to BBB (HBMEC) and glioma cells (U87 cells) evaluated in terms of physicochemical properties, cellular uptake, permeability in a 2D-BBB model, and tumor growth inhibition. Monte Carlo simulations elucidated CPP adsorption patterns. The permeability studies revealed that targeted usNLCs, especially usNLCs Tf and usNLCs CPP4 , exhibited an increased permeability coefficient compared to the non-targeted usNLCs. Functionalized usNLCs evidenced enhanced uptake in BBB cells, with smaller CPPs showing higher internalization (CPP1 and CPP2). Similarly, functionalized usNLCs exhibited more significant cytotoxicity in glioma cells, with specific CPPs promoting favorable internalization. Analysis of the endocytic pathway indicated that usNLCs CPPs were mainly internalized by direct translocation and caveolae-mediated endocytosis. Optimal usNLCs with dual targeting capabilities to both BBB and GB cells provide a promising therapeutic strategy for GB., Competing Interests: Declaration of conflict of interests The authors declare no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)