Prognosis Of Glioblastoma Patients Research Articles

TMIC-86. THE ROLE AND THERAPEUTIC RESEARCH OF NETS IN PROMOTING TMZ RESISTANCE IN GLIOBLASTOMA

Abstract OBJECTIVE This study aims to investigate the issue of resistance to temozolomide (TMZ) treatment in high-grade glioblastoma (GBM), specifically the association between TMZ resistance, the tumor microenvironment (TME), and neutrophil activity. The research hypothesis posits that changes in neutrophils induced by TMZ treatment, particularly the formation of neutrophil extracellular traps (NETs), may lead to TMZ resistance in GBM cells. METHODS The study utilized clinical data analysis and animal model research to evaluate changes in neutrophils during TMZ treatment and their impact on treatment efficacy. Proteomics analysis and high-throughput sequencing were employed to investigate the effect of TMZ on cytokine secretion by GBM cells and how these cytokines stimulate the release of NETs. Additionally, gene ontology (GO) analysis and bioinformatics methods were used to study how NETs promote the epithelial-mesenchymal transition (EMT) process and TMZ resistance by activating specific signaling pathways such as Jak-Stat3. RESULTS The study found that TMZ treatment led to increased neutrophil infiltration, which was associated with poor prognosis in GBM patients. TMZ treatment altered the levels of cytokines secreted by GBM cells, particularly IL-6, promoting the release of NETs by neutrophils. The formation of NETs was closely related to the activation of Stat3 signaling and the promotion of the EMT process in tumor cells, thereby enhancing TMZ resistance. Magnesium-based micromotors were found to improve TMZ efficacy by scavenging ROS production in neutrophils, inhibiting the release of NETs. CONCLUSION This study confirms the association between TMZ resistance and neutrophil activity, particularly the role of NETs in promoting EMT and resistance. These findings provide new insights into the treatment of GBM and offer a theoretical basis for the development of therapeutic strategies targeting NETs, which may improve the response of glioblastoma to TMZ treatment by inhibiting ROS production. The development of this novel therapeutic approach offers new treatment options for postoperative chemotherapy in GBM.

Bioinformatic analysis constructs an optimal prognostic index for survival-related variables (OPISV) based on whole-genome expression data in Glioblastoma

PurposeUsing clinical information and transcriptomic sequencing data from glioblastoma (GBM) patients in the TCGA database to perform gene-by-gene analysis that is aligned with individual patient characteristics and develop an optimal prognostic index of survival-related variables (OPISV) through iterative machine learning techniques to predict the prognosis of GBM patients. Study designThe TCGA dataset was utilized as the training dataset, while two GEO datasets served as independent validation cohorts. Initially, survival analysis (p < 0.001***), differential gene expression analysis (p < 0.05*), and univariate Cox regression analysis (p < 0.05*) were employed to identify genes that are highly correlated with patient prognosis and exhibit significant differences in survival status. Subsequently, incorporating the non-excludable variable of age, a multivariate Cox regression analysis was performed in a stepwise manner to construct the OPISV. Finally, logistic and LASSO regressions were used to validate the association between the identified genes and patient survival. The OPISV performance is evaluated and its potential mechanisms are explored. ResultsAge, CTSD, PTPRN, PTPRN2, NSUN5, DNAJC30 and SOX21 emerged as the optimal variables through multivariate Cox regression iterations. Further analysis characterized Age, PTPRN and DNAJC30 as independent prognostic risk factors for constructing OPISV, which is validated with external GEO datasets and GEPIA database. In OPISV_high populations, significantly upregulated GABAergic synapse function was exposed. Differential genes identified from gene clustering of the GABAergic synapse pathway and gene module highly correlated with GABAergic synapse in the WGCNA analysis are pointing unequivocally to the glioma progress. ConclusionOPISV is feasible for predicting patient survival, as it may serve as a potential mechanism underlying the involvement of GABAergic synapses in the progression of GBM.

The peritumoral edema index and related mechanisms influence the prognosis of GBM patients.

Peritumoral brain edema (PTBE) represents a characteristic phenotype of intracranial gliomas. However, there is a lack of consensus regarding the prognosis and mechanism of PTBE. In this study, clinical imaging data, along with publicly available imaging data, were utilized to assess the prognosis of PTBE in glioblastoma (GBM) patients, and the associated mechanisms were preliminarily analyzed. We investigated relevant imaging features, including edema, in GBM patients using ITK-SNAP imaging segmentation software. Risk factors affecting progression-free survival (PFS) and overall survival (OS) were assessed using a Cox proportional hazard regression model. In addition, the impact of PTBE on PFS and OS was analyzed in clinical GBM patients using the Kaplan-Meier survival analysis method, and the results further validated by combining data from The Cancer Imaging Archive (TCIA) and The Cancer Genome Atlas (TCGA). Finally, functional enrichment analysis based on TCIA and TCGA datasets identified several pathways potentially involved in the mechanism of edema formation. This study included a total of 32 clinical GBM patients and 132 GBM patients from public databases. Univariate and multivariate analyses indicated that age and edema index (EI) are independent risk factors for PFS, but not for OS. Kaplan-Meier curves revealed consistent survival analysis results between IE groups among both clinical patients and TCIA and TCGA patients, suggesting a significant effect of PTBE on PFS but not on OS. Furthermore, functional enrichment analysis predicted the involvement of several pathways related mainly to cellular bioenergetics and vasculogenic processes in the mechanism of PTBE formation. While these novel results warrant confirmation in a larger patient cohort, they support good prognostic value for PTBE assessment in GBM. Our results indicate that a low EI positively impacts disease control in GBM patients, but this does not entirely translate into an improvement in OS. Multiple genes, signaling pathways, and biological processes may contribute to the formation of peritumoral edema in GBM through cytotoxic and vascular mechanisms.

Pathomics models for CD40LG expression and prognosis prediction in glioblastoma

Glioblastoma (GBM) is the most prevalent primary malignant tumor of the nervous system. In this study, we utilized pathomics analysis to explore the expression of CD40LG and its predictive value for the prognosis of GBM patients. We analyzed the expression differences of CD40LG in GBM tissue and normal brain tissue, along with performing survival prognosis analysis. Additionally, histopathological sections of GBM were used to screen for pathological features. Subsequently, SVM and LR pathomics models were constructed, and the models’ performance was evaluated. The pathomics model was employed to predict CD40LG expression and patient prognosis. Furthermore, we investigated the potential molecular mechanisms through enrichment analysis, WGCNA analysis, immune correlation analysis, and immune checkpoint analysis. The expression level of CD40LG was significantly increased in GBM. Multivariate analysis demonstrated that high expression of CD40LG is a risk factor for overall survival (OS) in GBM patients. Five pathological features were identified, and SVM and LR pathomics models were constructed. Model evaluation showed promising predictive effects, with an AUC value of 0.779 for the SVM model, and the Hosmer–Lemeshow test confirmed the model’s prediction probability consistency (P > 0.05). The LR model achieved an AUC value of 0.785, and the Hosmer–Lemeshow test indicated good agreement between the LR model’s predicted probabilities and the true value (P > 0.05). Immune infiltration analysis revealed a significant correlation between the pathomics score (PS) and the degree of infiltration of activated DC cells, T cells CD4 naïve, Macrophages M2, Macrophages M1, and T cells CD4 memory resting. Our results demonstrate that the pathomics model exhibits predictability for CD40LG expression and GBM patient survival. These findings can be utilized to assist neurosurgeons in selecting optimal treatment strategies in clinical practice.

The mutated in colorectal cancer (MCC) gene can serve as a potential biomarker of glioblastoma.

The mutated in colorectal cancer (MCC) gene was initially identified as a candidate tumor suppressor gene in colorectal cancer, acting as a negative regulator of cell cycle progression. However, its functional roles in brain tumors, particularly glioblastoma, remain largely unexplored. This study reveals a significant association between MCC status and glioblastoma. We explored MCC expression in the glioblastoma database, patient samples, and cell lines. We investigated the proliferation and migration of the cell lines in MCC gene knockdown using small interfering RNA. In vitro analyses revealed elevated protein and mRNA levels of MCC in several glioblastoma cell lines (U118MG and T98G). Silencing MCC expression via siRNA-mediated knockdown resulted in increased proliferation and migration of these cell lines. Supporting these findings, analyses of The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and Genotype-Tissue Expression (GTEx) databases confirmed higher MCC expression in glioblastoma tumors than in normal brain tissue. Importantly, we observed that high MCC expression was associated with poor prognosis in glioblastoma patients, highlighting its potential role in disease progression. Additionally, this study identifies a nuclear localization of MCC in the glioblastoma cell line. These findings indicate that MCC expression is significantly upregulated in glioblastoma and may play a role in its pathophysiology, warranting further investigation.

Construction and validation of cell cycle-related prognostic genetic model for glioblastoma.

Glioblastoma (GBM) is a common primary malignant brain tumor and the prognosis of these patients remains poor. Therefore, further understanding of cell cycle-related molecular mechanisms of GBM and identification of appropriate prognostic markers and therapeutic targets are key research imperatives. Based on RNA-seq expression datasets from The Cancer Genome Atlas database, prognosis-related biological processes in GBM were screened out. Gene Set Variation Analysis (GSVA), LASSO-COX, univariate and multivariate Cox regression analyses, Kaplan-Meier survival analysis, and Pearson correlation analysis were performed for constructing a predictive prognostic model. A total of 58 cell cycle-related genes were identified by GSVA and analysis of differential expression between GBM and control samples. By univariate Cox and LASSO regression analyses, 8 genes were identified as prognostic biomarkers in GBM. A nomogram with superior performance to predict the survival of GBM patients was established regarding risk score, cancer status, recurrence type, and mRNAsi. This study revealed the prognostic value of cell cycle-related genes in GBM. In addition, we constructed a reliable model for predicting the prognosis of GBM patients. Our findings reinforce the relationship between cell cycle and GBM and may help improve the prognostic assessment of patients with GBM. Our predictive prognostic model, based on independent prognostic factors, enables tailored treatment strategies for GBM patients. It is particularly useful for subgroups with uncertain prognosis or treatment challenges.

Vitamin B6 Pathway Maintains Glioblastoma Cell Survival in 3D Spheroid Cultures.

Glioblastoma (GBM) is a deadly brain cancer. The prognosis of GBM patients has marginally improved over the last three decades. The response of GBMs to initial treatment is inevitably followed by relapse. Thus, there is an urgent need to identify and develop new therapeutics to target this cancer and improve both patient outcomes and long-term survival. Metabolic reprogramming is considered one of the hallmarks of cancers. However, cell-based studies fail to accurately recapitulate the in vivo tumour microenvironment that influences metabolic signalling and rewiring. Against this backdrop, we conducted global, untargeted metabolomics analysis of the G7 and R24 GBM 2D monolayers and 3D spheroid cultures under identical cell culture conditions. Our studies revealed that the levels of multiple metabolites associated with the vitamin B6 pathway were significantly altered in 3D spheroids compared to the 2D monolayer cultures. Importantly, we show that pharmacological intervention with hydralazine, a small molecule that reduces vitamin B6 levels, resulted in the cell death of 3D GBM spheroid cultures. Thus, our study shows that inhibition of the vitamin B6 pathway is a novel therapeutic strategy for the development of targeted therapies in GBMs.

A novel protein encoded by circCOPA inhibits the malignant phenotype of glioblastoma cells and increases their sensitivity to temozolomide by disrupting the NONO–SFPQ complex

Glioblastoma (GBM) represents a primary malignant brain tumor. Temozolomide resistance is a major hurdle in GBM treatment. Proteins encoded by circular RNAs (circRNAs) can modulate the sensitivity of multiple tumor chemotherapies. However, the impact of circRNA-encoded proteins on GBM sensitivity to temozolomide remains unknown. Herein, we discover a circRNA (circCOPA) through the circRNA microarray profile in GBM samples, which can encode a novel 99 amino acid protein (COPA-99aa) through its internal ribosome entry site. Functionally, circCOPA overexpression in GBM cells inhibits cell proliferation, migration, and invasion in vitro and growth in vivo. Rather than itself, circCOPA mainly functions as a suppressive effector by encoding COPA-99aa. Moreover, we reveal that circCOPA is downregulated in GBM tissues and high expression of circCOPA is related to a better prognosis in GBM patients. Mechanistically, a heteromer of SFPQ and NONO is required for double-strand DNA break repair. COPA-99aa disrupts the dimerization of NONO and SFPQ by separately binding with the NONO and SFPQ proteins, thus resulting in the inhibition of proliferation or invasion and the increase of temozolomide-induced DNA damage in GBM cells. Collectively, our data suggest that circCOPA mainly contributes to inhibiting the GBM malignant phenotype through its encoded COPA-99aa and that COPA-99aa increases temozolomide-induced DNA damage by interfering with the dimerization of NONO and SFPQ. Restoring circCOPA or COPA-99aa may increase the sensitivity of patients to temozolomide.

Combined Fluorescence-Guided Surgery with 5-Aminolevulinic Acid and Fluorescein in Glioblastoma: Technical Description and Report of 100 Cases.

Fluorescence-guided resection (FGR) of glioblastomas has been previously explored with the use of 5-amivelulinic acid (5-ALA) and sodium fluoresceine (SF), allowing us to maximize the extent of resection (EoR). In this study, we highlight the most relevant concerns regarding this technique and present the methods and results from the experience of our center. A case series of 100 patients operated on in AOU Città della Salute e della Scienza in Turin with a histological diagnosis of glioblastoma (grade IV, according to WHO 2021) was retrospectively analyzed. Both 5-ALA and SF were administered and intraoperatively assessed with an optical microscope. 5-ALA is the only approved drug for FGR in glioblastoma, reporting an increased EoR. Nevertheless, SF can be positively used in addition to 5-ALA to reduce the risk of false positives without increasing the rate of adverse effects. In our experience, SF was used to guide the initial phase of resection while 5-ALA was used to visualize tumor spots within the surgical cavity. In 96% of cases, gross total resection was achieved, with supra-maximal resection in 11% of cases. Combined FGR using 5-ALA and SF seems to be a promising method of increasing the extent of resection and to improving the prognosis in glioblastoma patients.

AB023. Early diagnosis and treatment lead to improve survival of glioblastoma patients.

Glioblastoma (GBM) is one of the worst prognostic cancers and one of the reasons is that GBM patients rapidly deteriorated and half of them had a Karnofsky performance status (KPS) with 70 or less at the initial presentation. We discuss the significance of early diagnosis and treatment to the clinical outcomes of GBM patients. Data of IDH-wildtype GBM patients treated at our institution between 2010 and 2019 were retrospectively reviewed. Patients were classified into early or late diagnosis groups with a threshold of 14 days from initial symptoms. Also, patients were divided into early, intermediate, and late surgery groups with thresholds of 21 and 35 days. Patients were also divided into two groups: neurosurgeon and non-neurosurgeon groups, based on the primary doctor whom patients sought for an initial evaluation. Representative symptoms and patient prognosis were examined. Of 153 patients, 72 and 81 were classified into the early and late diagnosis groups. The proportion of patients with preoperative KPS scores ≥90 was 48.6% and 29.6% in the early and late diagnosis groups (P=0.01). Median overall survival was significantly longer in the early surgery group (n=43) than in the late surgery group (n=86) (28.4 vs. 18.7 months, P=0.006). The neurosurgeon group exhibited a significantly shorter duration from the first hospital visit to the first surgery than the non-neurosurgeon group (18 vs. 29 days, P<0.001). Furthermore, the overall survival of the neurosurgeon group was significantly more prolonged than that of the non-neurosurgeon group (22.9 vs. 14.0 months, P=0.04). Early diagnosis and surgery within 3 weeks from the initial symptoms are associated with improved patient survival. Early GBM treatment will be beneficial for patients with GBM. A short duration from the first hospital visit to the first surgery is essential in enhancing GBM patient prognosis.

HMGB1/TREM2 positive feedback loop drives the development of radioresistance and immune escape of glioblastoma by regulating TLR4/Akt signaling

BackgroundRadioresistance and immune escape are crucial reasons for unsatisfactory therapeutic effects of glioblastoma (GBM). Although triggering receptor expressed on myeloid cells-2 (TREM2) involved in forming immunosuppressive microenvironment, but the underlying mechanism and its roles in mediating cancer radioresistance remain unclear, moreover, the efficient delivery of drugs targeting TREM2 to GBM encounters serious challenges. Hence, this study aimed to elucidate the effect and mechanisms of targeted TREM2 silencing on reversing the radioresistance and immune escape of GBM aided by a glutathione-responsive biomimetic nanoparticle (NP) platform.MethodsRadioresistant GBM cell lines and TREM2 stable knockdown GBM cell lines were firstly established. RNA sequencing, colony formation assay, western blot, enzyme-linked immunosorbent assay and co-immunoprecipitation assay were used to detect the molecular mechanisms of TREM2 in regulating the radioresistance and immune escape of GBM. The glutathione-responsive biomimetic NP, angiopep-2 (A2)- cell membrane (CM)-NP/siTREM2/spam1, was then constructed to triply and targeted inhibit TREM2 for in vivo study. Orthotopic GBM-bearing mouse models were established to evaluate the anti-GBM effect of TREM2 inhibition, multiplex immunofluorescence assay was conducted to detect the infiltration of immune cells.ResultsTREM2 was a regulator in accelerating the radioresistance and immune escape of GBM through participating in DNA damage repair and forming a positive feedback loop with high mobility group box 1 (HMGB1) to cascade the activation of Toll-like receptor 4 (TLR4)/protein kinase B (Akt) signaling. A2-CM-NP/siTREM2/spam1 was successfully synthesized with excellent passive targeting, active targeting and homologous targeting, and the in vivo results exhibited its remarkable anti-GBM therapeutic effect through promoting the infiltration of type 1 helper T cells and CD8+T cells, reducing the infiltration of type 2 helper T cells and regulatory T cells, repolarizing macrophages to M1-type, and decreasing the secretion of pro-tumor and immunosuppressive cytokines.ConclusionsTargeting TREM2 therapy is a promising avenue for optimizing radiotherapy and immunotherapy to improve the prognosis of GBM patients.

Hemoglobin, albumin, lymphocytes and platelets (HALP) score as a predictor of survival in patients with glioblastoma (GBM)

BackgroundWe aimed to investigate whether the HALP score was a predictor of survival in patients with Glioblastoma (GBM).MethodsA total of 84 Glioblastoma (GBM) patients followed in our clinic were included in the study. HALP scores were calculated using the preoperative hemoglobin, albumin, lymphocyte and platelet results of the patients. For the HALP score, a cut-off value was found by examining the area below the receiver operating characteristic (ROC) curve. Patients were divided into two groups as low and high according to this cut-off value. The relationships among the clinical, dermographic and laboratory parameters of the patients were examined using these two groups.ResultsMedian OS, PFS, HALP score, NLR, PLR were 15 months (1.0–78.0), 8 months (1.0–66.0), 37.39 ± 23.84 (min 6.00-max 132.31), 4.14, 145.07 respectively. A statistically significant correlation was found between HALP score and OS, PFS, NLR, PLR, ECOG-PS status using Spearman’s rho test (p = 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.026 respectively). For the HALP score, a cut-off value of = 37.39 (AUC = 0.698, 95% CI, p < 0.002) was found using ROC analysis. Median OS was 12 (6.99–17.01) months in the low HALP group and 21 (11.37–30.63) months in the high HALP group (p = 0.117). NLR and PLR were significantly lower in the HALP high group (p < 0.001, p < 0.001 respectively). The ratio of receiving treatment was significantly higher in the high HALP group (p < 0.05). In Multivariate analysis, significant results were found for treatment status and ECOG-PS status (p < 0.001, p = 0.038 respectively).ConclusionsThe HALP score measured at the beginning of treatment seems to have predictive importance in the prognosis of GBM patients. A HALP score of > 37.39 was associated with prolonged survival in high-grade brain tumors.

Identification and Prognostic Value of m6A-Related Genes in Glioblastoma.

N6-methyladenosine (m6A) is one of the most common forms of mRNA modification, which is dynamically regulated by the m6A-related genes; however, its effect in glioblastoma (GBM) is still unknown. We sought to investigate the association between m6A-related genes (m6A-RGs) and GBM. Transcriptome data and the relevant clinical data were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. The m6A-RGs were identified from differently expressed genes, and COX and lasso regression models were applied to locate the prognosis-related genes. We identified 15 out of 19 m6A-RGs differentially expressed between GBM and nontumor tissues. We identified two subgroups of GBM (clusters 1 and 2) by applying consensus clustering. Compared with the cluster 1 subgroup, the cluster 1 subgroup correlates with a poorer prognosis, and most of the 19 m6A-RGs are higher expressed in cluster 1. Through univariate Cox and lasso regression model, we identified three m6A-RGs, namely HNRNPC, ALKBH5, and FTO, which were used to construct a Cox regression risk model to predict the prognosis of GBM patients. We identified a valuable m6A model for predicting the prognosis of GBM patients, which can provide useful epigenetic biomarkers.

Humanin activates integrin αV–TGFβ axis and leads to glioblastoma progression

The role of mitochondria peptides in the spreading of glioblastoma remains poorly understood. In this study, we investigated the mechanism underlying intracranial glioblastoma progression. Our findings demonstrate that the mitochondria-derived peptide, humanin, plays a significant role in enhancing glioblastoma progression through the intratumoral activation of the integrin alpha V (ITGAV)–TGF beta (TGFβ) signaling axis. In glioblastoma tissues, humanin showed a significant upregulation in the tumor area compared to the corresponding normal region. Utilizing multiple in vitro pharmacological and genetic approaches, we observed that humanin activates the ITGAV pathway, leading to cellular attachment and filopodia formation. This process aids the subsequent migration and invasion of attached glioblastoma cells through intracellular TGFβR signaling activation. In addition, our in vivo orthotopic glioblastoma model provides further support for the pro-tumoral function of humanin. We observed a correlation between poor survival and aggressive invasiveness in the humanin-treated group, with noticeable tumor protrusions and induced angiogenesis compared to the control. Intriguingly, the in vivo effect of humanin on glioblastoma was significantly reduced by the treatment of TGFBR1 inhibitor. To strengthen these findings, public database analysis revealed a significant association between genes in the ITGAV–TGFβR axis and poor prognosis in glioblastoma patients. These results collectively highlight humanin as a pro-tumoral factor, making it a promising biological target for treating glioblastoma.

KCa channel targeting impairs DNA repair and invasiveness of patient-derived glioblastoma stem cells in culture and orthotopic mouse xenografts which only in part is predictable by KCa expression levels.

Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance particularly of mesenchymal glioblastoma stem-like cells (GSCs) has been proposed to contribute to therapy failure. Recently, we have shown that a mesenchymal-to-proneural mRNA signature of patient derived GSC-enriched (pGSC) cultures associates with in vitro radioresistance and gel invasion. Importantly, this pGSC mRNA signature is prognostic for patients' tumor recurrence pattern and overall survival. Two mesenchymal markers of the mRNA signature encode for IKCa and BKCa Ca2+-activated K+ channels. Therefore, we analyzed here the effect of IKCa- and BKCa-targeting concomitant to (fractionated) irradiation on radioresistance and glioblastoma spreading in pGSC cultures and in pGSC-derived orthotopic xenograft glioma mouse models. To this end, in vitro gel invasion, clonogenic survival, in vitro and in vivo residual DNA double strand breaks (DSBs), tumor growth, and brain invasion were assessed in the dependence on tumor irradiation and K+ channel targeting. As a result, the IKCa- and BKCa-blocker TRAM-34 and paxilline, respectively, increased number of residual DSBs and (numerically) decreased clonogenic survival in some but not in all IKCa- and BKCa-expressing pGSC cultures, respectively. In addition, BKCa- but not IKCa-blockade slowed-down gel invasion in vitro. Moreover, systemic administration of TRAM-34 or paxilline concomitant to fractionated tumor irradiation increased in the xenograft model(s) residual number of DSBs and attenuated glioblastoma brain invasion and (numerically) tumor growth. We conclude, that KCa-blockade concomitant to fractionated radiotherapy might be a promising new strategy in glioblastoma therapy.

The relationship between prognosis and temporal muscle thickness in 102 patients with glioblastoma

Temporal muscle thickness measured on 3D MRI has recently been linked to prognosis in glioblastoma patients and may serve as an independent prognostic indicator. This single-center study looked at temporal muscle thickness and prognosis in patients with primary glioblastoma. Overall survival was the major study outcome. For a retrospective analysis from 2010 to 2020, clinical data from 102 patients with glioblastoma at the Department of Oncology Radiotherapy of the First Affiliated Hospital of Dalian Medical University were gathered. Fifty-five cases from 2016 to 2020 contained glioblastoma molecular typing data, of which 45 were IDH wild-type glioblastomas and were analysed separately. TMT was measured on enhanced T1-weighted magnetic resonance images in patients with newly diagnosed glioblastoma.Overall patient survival (OS) was calculated by the Kaplan–Meier method and survival curves were plotted using the log-rank-sum test to determine differences between groups, and multifactorial analyses were performed using a Cox proportional-risk model.The median TMT for 102 patients was 6.775 mm (range: 4.95–10.45 mm). Patients were grouped according to median TMT, and the median overall survival (23.0 months) was significantly longer in the TMT > median group than in the TMT median group (P 0.001; Log-rank test). Analysing 45 patients with IDH wild type alone, the median overall survival (12 months) of patients in the TMT > median group was significantly longer than that of patients in the TMT ≤ median group (8 months) (P < 0.001; Log-rank test).TMT can serve as an independent prognostic factor for glioblastoma.

SMYD2 induced PGC1α methylation promotes stemness maintenance of glioblastoma stem cells.

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. 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. 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. 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.

Suppression of Glioblastoma Stem Cell Potency and Tumor Growth via LRRK2 Inhibition.

Leucine-rich repeat kinase 2 (LRRK2), a large GTP-regulated serine/threonine kinase, is well-known for its mutations causing late-onset Parkinson's disease. However, the role of LRRK2 in glioblastoma (GBM) carcinogenesis has not yet been fully elucidated. Here, we discovered that LRRK2 was overexpressed in 40% of GBM patients, according to tissue microarray analysis, and high LRRK2 expression correlated with poor prognosis in GBM patients. LRRK2 and stemness factors were highly expressed in various patient-derived GBM stem cells, which are responsible for GBM initiation. Canonical serum-induced differentiation decreased the expression of both LRRK2 and stemness factors. Given that LRRK2 is a key regulator of glioma stem cell (GSC) stemness, we developed DNK72, a novel LRRK2 kinase inhibitor that penetrates the blood-brain barrier. DNK72 binds to the phosphorylation sites of active LRRK2 and dramatically reduced cell proliferation and stemness factors expression in in vitro studies. Orthotopic patient-derived xenograft mouse models demonstrated that LRRK2 inhibition with DNK72 effectively reduced tumor growth and increased survival time. We propose that LRRK2 plays a significant role in regulating the stemness of GSCs and that suppression of LRRK2 kinase activity leads to reduced GBM malignancy and proliferation. In the near future, targeting LRRK2 in patients with high LRRK2-expressing GBM could offer a superior therapeutic strategy and potentially replace current clinical treatment methods.

Abstract 4989: Targeting IL-1β mitigates radiation induced MDSC expansion &amp; improves survival in glioblastoma

Abstract Background: Our previous research demonstrated that radiation therapy (RT) for glioblastoma (GBM) induces aberrant myelopoiesis, increasing production of myeloid derived suppressor cells (MDSCs) and exacerbating T-cell suppression. However, the precise biological mechanisms underlying this phenomenon remain unclear. This study aims to elucidate the role of the pro-inflammatory cytokine interleukin-1beta (IL-1β) in RT-induced myelopoiesis and its correlation with poor prognosis in GBM patients. Methods: We conducted an extensive analysis of circulatory immune cells and pro-inflammatory cytokines in GBM patients treated with chemoradiotherapy. Using an orthotopic mouse model of GBM, we investigated the impact of IL-1β on myelopoiesis and survival. Functional assays were employed to examine MDSC expansion. Multi-color flow cytometry was used for immune profiling. Results: We found that RT elevated the plasma IL-1β concentration in both GBM patients and GBM-bearing mice, which also corresponded with an increase of MDSC in blood. In the murine GBM model, RT appeared to promote hematopoietic stem (HSPC) differentiation towards myelopoiesis. This led to increased MDSC precursor cells in the bone marrow, elevated circulating MDSCs in blood, and more infiltration of MDSCs in the tumor microenvironment (TME). Similar effects were observed in GBM-bearing mice following the administration of exogenous IL-1β. In contrast, inhibition of IL-1β using anti-IL-1β antibody during RT led to reduced myelopoiesis. When anti-IL-1β antibody was combined with functional inhibition of MDSCs using phosphodiesterase-5 inhibitor-tadalafil during RT, we observed decreased MDSC infiltration and increased CD8+ T cell infiltration in the TME. The combination approach also extended the survival of GBM-bearing mice after RT longer than either drug alone. Conclusions: Irradiation of GBM appears to induce IL-1β to promote aberrant myelopoiesis and MDSC expansion. A multi-pronged approach to inhibit MDSC production using IL-1β inhibitor and MDSC function using tadalafil during RT may be a promising approach to overcome the immune-suppressive TME of GBM. Citation Format: Subhajit Ghosh, Jiayi Huang, David DeNardo, Dennis Hallahan, Jerry Jaboin, Dinesh Thotala. Targeting IL-1β mitigates radiation induced MDSC expansion &amp; improves survival in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4989.

Abstract 3079: AMPK-HIF-1α signaling enhances glucose-derived de novoserine biosynthesis to promote glioblastoma growth

Abstract Cancer cells undergo cellular adaptation through metabolic reprogrammin to sustain survival and rapid growth under various stress conditions. However, it remains unknown how brain tumors modulate their metabolic flexibility in the naturally serine/glycine (S/G)-deficient brain microenvironment. We used a range of primary/stem-like and established glioblastoma (GBM) cell models in vitro and in vivo. To identify regulatory mechanisms of S/G deprivation induced metabolic flexibility, we employed high throughput RNA-sequencing, transcriptomic analysis, metabolic flux analysis, metabolites analysis, chromatin immunoprecipitation (ChIP), luciferase reporter, nuclear fractionation, cycloheximide-chase, and glucose consumption. The clinical significances were analyzed in the genomic database (GSE4290) and in human GBM specimens. The high throughput RNA-sequencing and transcriptomic analysis demonstrate that the de novo serine synthesis pathway (SSP) and glycolysis are highly activated in GBM cells under S/G deprivation conditions. Mechanistically, S/G deprivation rapidly induces reactive oxygen species (ROS)-mediated AMP-activated protein kinase (AMPK) activation and AMPK dependent hypoxia-inducible factor (HIF)-1α stabilization and transactivation. Activated HIF-1α in turn promotes expression of SSP enzymes phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH). In addition, HIF-1α-induced expression of glycolytic genes (GLUT1, GLUT3, HK2, and PFKFB2) promotes glucose uptake, glycolysis, and glycolytic flux to fuel SSP, leading to elevated de novo serine and glycine biosynthesis, NADPH/NADP+ ratio, and proliferation and survival of GBM cells. Analyses of human GBM specimens reveal that levels of overexpressed PHGDH, PSAT1, and PSPH are positively correlated with levels of AMPK T172 phosphorylation and HIF-1α expression and poor prognosis of GBM patients. Our findings reveal that metabolic stress-enhanced glucose-derived de novo serine biosynthesis is a critical metabolic feature of GBM cells and highlight the potential to target SSP for treating human GBM. Citation Format: Hye Jin Yun, Jong-Ho Lee. AMPK-HIF-1α signaling enhances glucose-derived de novoserine biosynthesis to promote glioblastoma growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3079.