Temozolomide (TMZ) resistance is a critical factor that affects the therapeutic efficacy in glioblastoma (GBM). Glutathione peroxidase 8 (GPX8), a ROS scavenging enzyme, is associated with poor prognosis in GBM. In this study, we comprehensively studied the role and mechanism of GPX8 in GBM resistance to TMZ. We found that GPX8 was upregulated in GBM cells, tissues, and TMZ-resistant GBM cells. In U87 TMZ-resistant cells, GPX8 knockdown significantly suppressed cell proliferation, reversed the epithelial-mesenchymal transition (EMT), and sensitized cells to TMZ. Moreover, GPX8 knockdown induced mitochondrial oxidative stress, leading to apoptosis in TMZ-resistant cells. TEA domain family member 4 (TEAD4) was upregulated in GBM cells and transactivates GPX8. GPX8 interacted with collagen triple helix repeat containing-1 (CTHRC1) and promoted its expression. Overexpression of TEAD4 or CTHRC1 reversed the suppressive effect of GPX8 knockdown on the malignant phenotypes of TMZ-resistant cells and antagonized its promotive effect on mitochondrial ROS generation and apoptosis. Furthermore, overexpression of GPX8 or CTHRC1 promoted EMT, reduced ROS levels, and lowered TMZ sensitivity in resistant cells. Crucially, the p38 MAPK/FOXO3 pathway inhibitor Ade was able to reverse these effects. GPX8 knockdown increased GBM sensitivity to TMZ, inhibited EMT, and elevated ROS levels in both xenograft models and glioma organoids. Overall, our results elucidated that TEAD4-driven GPX8 suppresses mitochondrial oxidative stress in TMZ-resistant cells through activation of the CTHRC1/p38 MAPK/FOXO3 pathway, which promotes TMZ resistance in GBM cells. These findings suggest that GPX8 may serve as a novel therapeutic target for overcoming TMZ resistance in GBM.

BACKGROUND:Gliomas are highly aggressive primary brain tumors with a dismal prognosis. Temozolomide (TMZ) serves as the first-line chemotherapeutic agent for glioma patients. However, the clinical efficacy of TMZ is severely limited by the inevitable development of acquired chemoresistance, which ultimately leads to tumor recurrence and treatment failure. Unraveling the molecular mechanisms underlying TMZ resistance is therefore critical for improving glioma prognosis. This study aimed to identify key genes driving TMZ resistance and explore their underlying mechanisms to provide novel therapeutic targets for overcoming this clinical challenge. METHODS:Differentially expressed genes (DEGs) between TMZ-resistant (LN229TR, U251TR, and U87TR) and TMZ-sensitive glioma cells were screened using GEO datasets. The intersecting DEGs were subjected to protein-protein interaction (PPI) network construction via the STRING database and visualized using Cytoscape software. Hub genes were identified by integrating the results from the Maximal Clique Centrality (MCC) and Density of Maximum Neighborhood Component (DMNC) algorithms. The expression patterns of candidate hub genes were validated in glioma cells, clinical tissues, and the Gene Expression Profiling Interactive Analysis (GEPIA) database. Functional assays, including cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine, colony formation, transwell, flow cytometry, and sphere formation assays, were performed to evaluate cell viability, proliferation, migration, apoptosis, and stem-like properties in vitro. Furthermore, a subcutaneous xenograft tumor model in mice was established to assess the in vivo therapeutic effects. RESULTS:A total of 320 intersecting DEGs were extracted from the three cell line groups, and interferon-induced protein with tetratricopeptide repeats 3 (IFIT3) along with 2'-5'-oligoadenylate synthetase like (OASL) were ultimately identified as the core hub genes. IFIT3 was selected for further investigation due to its significant upregulation in both low-grade gliomas and glioblastoma compared to normal brain tissues. Consistently, IFIT3 expression was remarkably elevated in TMZ-resistant glioma tissues and cell lines (P < 0.05), which exhibited significantly higher half-maximal inhibitory concentration (IC50) values of TMZ than their sensitive counterparts (P < 0.05). Functionally, IFIT3 silencing significantly decreased the IC50 of TMZ (P < 0.05), suppressed cell proliferation (P < 0.05), migration (P < 0.05), and stem-like traits (P < 0.05), and induced apoptosis (P < 0.05) in resistant glioma cells. Conversely, ectopic IFIT3 expression exerted opposite effects on cell proliferation, migration, and stem-like traits and notably increased the ratios of phosphorylated phosphoinositide 3-kinase (PI3K) to total PI3K and phosphorylated AKT to total AKT (P < 0.05); however, these effects induced by IFIT3 overexpression were effectively reversed by the PI3K inhibitor LY294002 (P < 0.05). In vivo experiments demonstrated that knocking down IFIT3 expression remarkably reduced tumor volume and weight upon TMZ treatment, accompanied by decreased expression levels of IFIT3, nuclear proliferation marker (Ki-67), and phosphorylated AKT in tumor tissues (P < 0.05). CONCLUSION:IFIT3 overexpression conferred TMZ resistance and promoted multiple malignant phenotypes in gliomas by activating the PI3K/AKT signaling pathway. Clinically, targeting IFIT3 might effectively re-sensitize resistant gliomas to TMZ, thereby offering a novel and actionable strategy to overcome chemoresistance and improve clinical outcomes for glioma patients.

INTRODUCTION:Gliomas are the most common malignant primary brain tumors in adults, with generally unfavorable outcomes. Although focal adhesion-related genes are implicated in glioma progression, their clinical applicability remains limited. METHODS:mRNA expression profiles were analyzed in 938 glioma samples from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA), with TCGA as the discovery cohort and CGGA as the validation cohort. Consensus clustering and LASSO Cox regression were used to construct a focal adhesion-related gene (FARG) signature. Survival analysis, pathway enrichment, immune infiltration, and drug response analyses were subsequently performed based on this signature. In vitro and in vivo assays were performed to investigate RAP1B, the gene with the highest coefficient in the FARG signature. RESULTS:A 9-gene FARG signature was identified and effectively stratified patients into high- and low-risk groups with significantly different outcomes. High-risk patients exhibited malignant molecular features, activation of oncogenic pathways, treatment resistance, and an immunosuppressive microenvironment. RAP1B contributed most to the risk score, was significantly upregulated in gliomas, and correlated with poor prognosis. Mechanistically, NFKB1 enhanced RAP1B transcription, promoting glioma proliferation, migration, and tumorigenesis. DISCUSSION:The FARG signature integrates molecular and immune characteristics of gliomas, offering a predictive model for patient prognosis. RAP1B, as a key molecular target, holds potential for improving patient survival. However, this study largely relies on public databases, and further validation in independent cohorts and functional models is required. CONCLUSION:This study establishes a FARG-based prognostic model and identifies RAP1B as a potential therapeutic target in glioma.

ObjectivesDespite the close association with patient clinical outcomes, dysregulated kinases in gliomas are not commonly used as clinical indicators. We aimed to identify a kinase-related gene signature for glioma patients that improves clinical risk-stratification.MethodsLeast absolute shrinkage and selection operator (LASSO) Cox regression analysis was conducted to identify kinase-related gene signature. The association between the risk model and patient survival, pathway activation, and immune suppression status was further explored. Additionally, cell proliferation and tumor formation assay were performed to evaluate the oncogenic roles of identified kinase gene.ResultsIn this study, we identified a 10-gene kinase signature in TCGA dataset that is significantly associated with poor overall survival (OS) in glioma patients. A consistent prediction ability for survival was further demonstrated in the CGGA dataset. In addition, the signature was significantly linked to malignant molecular signatures, such as IDH wild type and non-codeletion of 1p19q. Moreover, the high-risk group exhibited a wide array of oncogenic biological pathways. Interestingly, the result showed that the kinase-related signature is tightly linked with immune suppression signatures, including immune infiltration of MDSCs and Tregs, and expression of immunosuppressive genes. Functionally, the oncogenic roles of WEE1 in gliomas were validated.ConclusionsThe findings present a novel kinase-related gene signature with potential value for survival prediction in gliomas.

[This retracts the article DOI: 10.1016/j.omtn.2017.12.014.].

Glioblastoma (GBM) is the most fatal primary brain malignancy in adults, with a median survival of approximately 15 months. The 2021 WHO classification redefined GBM as exclusively IDH-wildtype based on its characteristic molecular and clinical features. In this study, we aimed to identify key prognostic genes in GBM, IDH-wildtype. Using univariate Cox proportional hazards regression analysis, PXN was identified as a critical upregulated gene in GBM, IDH-wildtype, significantly associated with poor prognosis. Its expression was further validated by qRT-PCR, western blotting, and immunohistochemistry. Functional assays revealed that elevated PXN enhances GBM malignancy, whereas its knockdown suppresses corresponding malignant features. Mechanistically, PXN and STAT3 form a positive feedback loop: STAT3 upregulates PXN transcription, and PXN, in turn, activates STAT3 by regulating SRC transcription. Additionally, PXN stabilizes YB-1 protein by inhibiting its ubiquitination. Further mRNA sequencing analysis demonstrated that YB-1 contributes to maintaining GBM malignancy through multiple signaling pathways. These results suggest that the STAT3-PXN positive feedback axis and the regulation of YB-1 stability by PXN may offer novel targets for GBM therapy.PXN is elevated in GBM, IDH-wildtype and associated with poor prognosis and malignant features. STAT3 directly promotes PXN transcription, and PXN reciprocally activates STAT3 by regulating SRC transcription. PXN stabilizes YB-1 protein by inhibiting its ubiquitin-mediated degradation.

<p>Supplementary figure legends and materials and methods</p>

<p>Supplementary Figure S3. PROS1 is located in GSCs.</p>

<p>Supplementary Figure S6. BGB324 inhibits mouse tumor cells.</p>

Supplementary Figure S4. Identification of T cells subpopulation in GBM dissociated tumor via CyTOF.

Increasing evidence has revealed a strong connection between the aldehyde dehydrogenase family member ALDH1A3 and tumorigenesis, therapy resistance, and prognosis in diverse types of cancer. However, the specific miRNA involved in the pathways that regulate ALDH1A3-mediated glioblastoma (GBM) radioresistance remains to be elucidated. In this study, we demonstrated a high expression of ALDH1A3 in GBM cells, which plays a critical role in their proliferation and radioresistance. We also identified miR-4524b-5p, which is downregulated in GBM, as the ALDH1A3 upstream regulator. Overexpression of miR-4524b-5p reduced proliferation and radioresistance in GBM cells. Moreover, silencing ALDH1A3 reduced PI3K/AKT/mTOR signaling and glycolytic activity in GBM cells, whereas inhibiting mTOR reversed the radioresistance effects of ALDH1A3 on these cells. In vivo experiments have evidenced that ALDH1A3 silencing and miR-4524b-5p overexpression significantly reduced tumor growth and GBM cells radioresistance. In summary, targeting the miR-4524b-5p and ALDH1A3 axis is a promising therapeutic strategy for treating GBM.

Gliomas are the most common lethal primary brain tumors with variable survival outcomes for patients. The extracellular matrix (ECM) is linked with clinical prognosis of glioma patients, but it is not commonly used as a clinical indicator. Herein, we investigated changes in ECM-related genes (ECMRGs) via analyzing the transcriptional data of 938 gliomas from TCGA and CGGA datasets. Based on least absolute shrinkage and selection operator (LASSO) Cox regression analysis, a 11-ECMRG signature that is strongly linked with overall survival (OS) in glioma patients was identified. This signature was characterized by high-risk and low-risk score patterns. We found that the patients in the high-risk group are significantly linked with malignant molecular features and worse outcomes. Univariate and multivariate Cox regression analyses suggested that the signature is an independent indicator for glioma prognosis. The prediction accuracy of the signature was verified through time-dependent receiver operating characteristic (ROC) curves and calibration plots. Further bioinformatics analyses implied that the ECMRG signature is strongly associated with the activation of multiple oncogenic and metabolic pathways and immunosuppressive tumor microenvironment in gliomas. In addition, we confirmed that the high-risk score is an indicator for a therapy-resistant phenotype. In addition to bioinformatics analyses, we functionally verified the oncogenic role of bone morphogenetic protein 1 (BMP1) in gliomas in vitro.

Gliomas, as the most lethal and malignant brain tumours in adults, remain a major challenge worldwide. DNA damage and repair-related genes (DDRRGs) appear to play a significant role in gliomas, but the studies of DDRRGs are still insufficient. Herein, we systematically explored and analysed 1547 DDRRGs in 938 glioma samples from TCGA and CGGA datasets. Using least absolute shrinkage and selection operator (LASSO) Cox regression analysis, we identified a 16-DDRRG signature, characterized by high-risk and low-risk patterns. This risk model harbours robust predictive capability for overall survival of glioma patients. We found the high-risk score is strongly associated with well-known malignant features of gliomas, such as the mesenchymal subtype, IDH-wildtype, 1p/19q non-codeletion and MGMT promoter unmethylated status. In addition, we found that the high-risk score is also linked with multiple oncogenic pathways and therapeutic resistance. Significantly, we found the high-risk group has higher enrichment of immunosuppressive cells (M2-type macrophages, Tregs and MDSCs) and immune inhibition biomarkers (PD-1, PD-L1 and CTLA-4). Lastly, we proved that SMC4, which has the highest positive regression coefficient in our risk model, is strongly linked with malignant progression and TMZ resistance of gliomas in a E2F1-dependent manner.

INTRODUCTION:Glioma is the most common malignant primary brain tumor with survival outcome for patients with lower-grade gliomas (LGGs) being quite variable. Epigenetic modifications in LGGs appear tightly linked to patient clinical outcomes but are not commonly used as clinical tools.AIMS:We aimed to derive an epigenetic enzyme gene signature for LGGs that would allow for improved clinical risk stratification.RESULTS:The study employed transcriptomic data of 711 lower-grade gliomas from three publically available data sets. Based on least absolute shrinkage and selection operator (LASSO) Cox regression analysis, we discovered a 13-gene epigenetic signature that strongly predicts poor overall survival in LGGs. The robust prediction ability for survival was further verified in two independent validation cohorts. The signature was also significantly associated with malignant molecular signatures including wild-type IDH, unmethylated MGMT promoter, and non-codeletion of 1p19q together with linkage to multiple oncogenic pathways. Interestingly, our results showed that immune infiltration of MDSCs together with mRNA expression of immune inhibition biomarkers was also positively correlated with the epigenetic signature. Lastly, we confirmed the oncogenic role of SMYD2 in glioma tumor cells in functional assays.CONCLUSIONS:We report a novel epigenetic gene signature that harbors robust survival prediction value for LGG patients that is tightly linked to activation of multiple oncogenic pathways.

FBXO17 is a newly studied F-box protein associated with high-grade glioma. However, its exact role in glioma remains unclear. In the present study, we aimed to investigate the role of FBXO17 in glioma both in vitro and in vivo and explore the underlying mechanism. Our results showed that FBXO17 mRNA and protein levels were upregulated in glioma cells including U87, U251, SHG44, and U-118-MG cells as compared to the HA1800 cells. Downregulation of FBXO17 significantly suppressed the cellular behaviors of glioma cells including cell proliferation, migration, and invasion. In addition, FBXO17 knockdown induced E-cadherin expression and inhibited N-cadherin and vimentin expression at mRNA and protein levels in glioma cells. In contrast, overexpression of FBXO17 promoted cell proliferation, migration, invasion and EMT process. Furthermore, FBXO17 regulated the Akt/GSK-3β/snail signaling pathway in glioma cells with significant changes in the expression levels of p-Akt, p-GSK-3β and snail. Additionally, inhibition of Akt by LY294002 reversed the effects of FBXO17 overexpression on cellular behaviors of glioma cells. Finally, in vivo mouse xenograft assay proved that downregulation of FBXO17 suppresses the tumorigenesis of glioma. In conclusion, these findings demonstrated that FBXO17 acted as a promotor of glioma development via modulating Akt/GSK-3β/snail signaling pathway.

As natural potential antioxidants suffer from low cellular uptake, the development of drug-loaded nanoplatforms may provide useful information about the treatment of spinal cord injury (SCI). In the present study, sesamol (SM)-loaded stearic acid (SA) -chitosan (CS) nanomicelles were fabricated and well-characterized. Afterwards, the neuroprotective effects of SM@SA-CS nanomicelles against lipopolysaccharide (LPS)-induced oxidative stress in NSC-34 cells was assessed by different cellular and molecular pathways. It was deduced that the size of synthesized SM@SA-CS was in the range of 10-20 nm and the hydrodynamic radii of SA-CA and SM@SA-CA nanomicelles were 53.12 ± 6.21 nm and 59.12 ± 7.31 nm, respectively. Furthermore, SM@SA-CS nanomicelles displayed a sustained drug release at physiological pH, potential dissolution rate and stability even up to 15 days. Cellular assay showed that SM@SA-CS nanomicelles co-incubation with LPS for 24 h in comparison with free drug remarkably regulated cell survival, membrane leakage, generation of ROS, activity of non-enzymatic and enzymatic antioxidant systems, and apoptotic and inflammatory signaling pathway through NF-ĸB signaling pathway. These data indicated that SM@SA-CS nanomicelles can be developed as a promising platform for the mitigation of oxidative stress-mediated apoptosis in neural cells.

Objective: This study aimed to investigate the changes in inflammatory cytokines and infection factors in patients with intracranial infection after intracranial tumor operation. Methods: Patients with meningioma admitted to our hospital from May 2015 to June 2018 were enrolled. Based on postoperative infection, the patients were divided into the infection group (n=309) and non-infection group (n=305). The levels of related inflammatory cytokines after operation were measured and the risk factors were determined by univariate analysis and multivariate logistic regression analysis. Results: Differences in the levels of serum C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were not obvious between the two groups of patients on the 1st day after operation (P>0.05). From the 3rd d after operation, the levels were remarkably higher than those in patients of the non-infection group, and differences in the levels of serum CRP, PCT, IL-6 and TNF-alpha between the two groups of patients became more obvious on the 7th and 14th d after operation (P<0.05). The multivariate Logistic regression analysis revealed that age, diabetes mellitus, operation time, posterior fossa operation and postoperative cerebrospinal fluid leakage were independent risk factors for patients with intracranial infection after intracranial tumor operation (P<0.05). Conclusion: Infection inflammatory cytokines, CRP, PCT, IL-6 and TNF-alpha, along with other infection factors, function as important indicators after Intracranial Tumor Operation, which provide new leads for the countermeasures of intracranial infection in clinical practice.

The highly infiltrative nature of glioblastoma (GBM) underscores limited response to current therapies and subsequent unfavorable clinical outcome. Despite the gross total resection of tumors located in the enhancing lesions, GBMs inevitably recur from the areas adjacent to the resection cavity that retains tumor cells with tumor-initiating capacity with therapy resistant nature (glioma-initiating cells: GICs). Here, we identified, in clinical GBM tumors, two mutually-exclusive glioma-initiating cell subpopulations in two different regions of GBM tumors, core- and edge-located glioma-initiating cells that co-exist in single tumors (Minata et al. Cell Reports. 2019). Following this observation, we further established patient-derived GBM clones from both tumor core and edge tissues, termed core-GICs and edge-GICs, and uncovered their distinct molecular signatures. Unexpectedly, we found that these two distinct GIC subpopulations retain the spatial identity, meaning that the core GICs locate themselves in the injected site, whereas the edge GICs initiated to form edge-like lesions, when xenografted into mouse brains. Through OMICs analyses, we identified CD38 as a key molecule to determine the edge phenotype both in vitro and in vivo. Collectively, our findings indicate, for the first time, that GBM cells are heterogeneous to be composed of tumor cells destined to be located in distinct regions of the tumors in a molecularly-defined manner.

Glioblastoma (GBM) remains the deadliest of all primary brain tumors with very few effective treatment options. Recently, we reported that high AXL expression is correlated with poor prognosis in GBM patients and demonstrated the therapeutic benefits of targeting AXL, a member of TAM receptor tyrosine kinase family using a novel small molecule inhibitor, BGB324 in immunocompetent mouse GBM models and xenografts of patient-derived glioma stem cells(GSCs). The promise of BGB324 in tumor burden management prompted us to develop a clinical trial with BGB324 as a single agent therapeutic with the goal to extend it as a combinatorial therapy in the future. Our surgical PK/PD clinical trial with BGB324 in recurrent GBM has been approved by the Brain Malignancy Steering Committee at the National Cancer Institute. Study treatment will consist of 2 cohorts of adult GBM patients, one (Group A) receiving the treatment pre-operatively and the other (Group B) receiving no treatment at all prior to surgery. First 5 patients recruited to Group A will be checked for the desired intra-tumoral drug concentration achieved to continue the trial. Group A will be supplemented by an additional 5 patients bringing the number to n=10 in each arm of the trial. Following surgical resection, patients in both cohorts will receive BGB324 daily in 21-day cycles. Treatment will be continued unless patients exhibit significant toxicity or substantial tumor progression. Our preclinical findings show the upregulation of AXL and its role in apoptosis induction in mesenchymal GBM as well as its association with MLK4, a serine threonine kinase we previously characterized as a mesenchymal GSC molecular target. Inhibition of phosphorylation of AXL and concomitant NF-kB activation in mesenchymal GSCs was found to be the nodal target of the drug action. An up-to-date information of the trial will be presented in detail.