Effects In Gliomas Research Articles

Association of TNFRSF19 with a TNF family-based prognostic model and subtypes in gliomas using machine learning

PurposeTNF family members (TFMs) play a crucial role in different types of cancers, with TNF Receptor Superfamily Member 19 (TNFRSF19) standing out as a particularly important member in this category. Further research is necessary to investigate the potential impact of TFMs on prognosis prediction and to elucidate the function and potential therapeutic targets linked to TNFRSF19 expression in gliomas. MethodsThree databases provided the data on gene expression and clinical information. Fourteen prognostic members were found through univariate Cox analysis and subsequently utilized to construct TFMs-based model in LASSO and multivariate Cox analyses. TFMs-based subtypes based on the expression profile were identified using an unsupervised clustering method. Machine learning algorithm identified key genes linked to prognostic model and subtype. A sequence of immune infiltrations was evaluated using the ssGSEA and ESTIMATE algorithms. Immunohistochemistry was used to examine the patterns of expression and the clinical significance of TNFRSF19. ResultsOur development of a prognostic model and subtypes based on the TNF family was successful, resulting in accurate predictions of prognosis. The findings indicate that TNFRSF19 exhibited strong performance. Upregulation of TNFRSF19 was correlated with malignant phenotypes and poor prognosis, which was confirmed through immunohistochemistry. TNFRSF19 played a role in reshaping the immunosuppressive microenvironment in gliomas, and multiple drug-targeted TNFRSF19 molecules were identified. ConclusionsThe TMF-based prognostic model and subtype can facilitate treatment decisions for glioma. TNFRSF19 is an outstanding representative of a predictor of prognosis and immunotherapy effect in gliomas.

Abstract A050: Ferritin, associated with worse overall survival in recurrent GBM, is reduced by combination of HDACi, ONC206 and radiation

Abstract Background: GBM is the most common primary brain malignancy with dismal prognosis. Current standard of care is chemoradiation&surgery. The main issue with GBM is the resistance & recurrence. GBM can have high Ferritin levels associated with disease progression & immunosuppression in the GBM TME. Ferritin light chain (FTL), a key protein in iron metabolism, is mutated in GBM leading to high ferritin levels (both light& heavy chain) & is associated with poor survival of (GBM) patients in part due to inhibition of ferroptosis. Panobinostat is a histone deacetylase inhibitor with antineoplastic & antiangiogenic effects in glioma. Imipridone ONC206 is under Phase I clinical development in treatment of adult & pediatric patients with newly diagnosed and/or recurrent primary brain tumors (NCT04732065 and NCT04541082).We investigated the novel combination of irradiation, Panobinostat and ONC206 with regard to GBM cell line sensitivity&ferritin levels. Materials & methods: We investigated cell viability and drug synergies of ONC206 plus Panobinostat with or without radiation in 4 human GBM cell lines at 72 hours. Changes in Ferritin level treatment in U87 & U251 cells were measured using cytokine profiling at 24 h time point. Information regarding recurrent cases of adult GBM from TCGA &GlioVis were used for survival data. Results: We previously have shown the synergy between Panobinostat, Irradiation and ONC206 (2023 AACR meeting). Treatment of U87 cells with Panobinostat and ONC206 at their IC50s +/- 4 Gy radiation at 24h time point led to reduction in secreted ferritin levels (Panobinostat alone: 26.3% decrease; ONC206 alone: 14.7% decrease; RT 4Gy alone 14.7% decrease; triple therapy: 32.2% decrease). In panobinostat treated U251 cells there was a 10% increase in ferritin at 24 h. ONC206 resulted in a reduction by 34.71%, 4 Gy RT caused a slight increase of 4% in ferritin amount while the triple showed 49.96% reduction in ferritin levels. mRNA expression of FTL gene (Ferritin Light Chain) is significantly higher in GBM tumors compared to normal brain tissue. From TCGA 17 cases of recurrent gliomas with FTL mutation were available with median survival of less than a year. In data from GlioVis of recurrent GBM cases 263 patients had high FTL with median survival of 12.6 months compared to 262 patients with low FTL with median survival of 14.9 months. Conclusions: GBM with high ferritin correlates with poor patient survival. FTL is associated with cell proliferation &angiogenesis of GBM cells & is protective from ferroptosis in glioma cells. ferritin may be a therapeutic target in recurrent & therapy resistant cases of GBM and ferroptosis modulating drugs &can be a novel treatment option. ONC206 & Panobinostat with irradiation is a novel combination & can be considered for temozolomide or radiation-resistant & recurrent cases. More studies are needed to investigate the mechanism & impact of ferritin in disease progression, therapy resistance& ferroptosis targeting therapeutics. We are currently exploring these directions including in vivo studies. Citation Format: Vida Tajiknia, Wafik El Deiry, Lanlan Zhou, William Macdonald, Praveen Srinivasan. Ferritin, associated with worse overall survival in recurrent GBM, is reduced by combination of HDACi, ONC206 and radiation [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr A050.

Let-7b-5p promotes triptolide-induced growth-inhibiting effects in glioma by targeting IGF1R.

Glioma is one of the most common malignancies of the central nervous system. The therapeutic effect has not been satisfactory despite advances in comprehensive treatment techniques. Our previous studies have found that triptolide inhibits glioma proliferation through the ROS/JNK pathway, but in-depth mechanisms need to be explored. Recent studies have confirmed that miRNAs may function as tumor suppressor genes or oncogenes and be involved in cancer development and progression. In this study, we found that let-7b-5p expression levels closely correlated with WHO grades and overall survival in patients in tumor glioma-CGGA-mRNAseq-325, and the upregulation of let-7b-5p can inhibit the proliferation and induce apoptosis of glioma cells. Functionally, upregulation of let-7b-5p increased the inhibitory effect on cell viability and colony formation caused by triptolide and promoted the apoptosis rate of triptolide-treated U251 cells. Conversely, downregulation of let-7b-5p had the opposite effect, indicating that let-7b-5p is a tumor suppressor miRNA in glioma cells. Moreover, target prediction, luciferase reporter assays and functional experiments revealed that IGF1R was a direct target of let-7b-5p. In addition, upregulation of IGF1R reversed the triptolide-regulated inhibition of cell viability but promoted glioma cell apoptosis and activated the ROS/JNK signaling pathway induced by triptolide. The results obtained in vivo experiments substantiated those from the in vitro experiments. In summary, the current study provides evidence that triptolide inhibits the growth of glioma cells by regulating the let-7b-5p-IGF1R-ROS/JNK axis in vitro and in vivo. These findings may provide new ideas and potential targets for molecularly targeted therapies for comprehensive glioma treatment.

P11.11.A VOLUMETRIC AND SPATIAL ANALYSES OF TREATMENT-RELATED INJURY IN GLIOMA

Abstract BACKGROUND As diffuse glioma cannot yet be cured, benefits of therapeutic strategies should be carefully balanced against their burden. Postoperative ischemia is a relatively common adverse event of surgery, which can lead to serious neurological deficits. Radiation therapy (RT) can cause post-RT lesions, which may cause clinical symptoms and can create a therapeutic impasse since they mimic tumor progression. We aimed to explore the spatial and volumetric tumor and treatment characteristics in relation to development of treatment-related effects in glioma. Materials and METHODS We retrospectively included 144 WHO grade II-IV supratentorial glioma cases, which were resected from 2012 till 2014 and had early postoperative MRI with diffusion-weighted imaging (DWI). Tumors were delineated on preoperative contrast-enhanced T1 MRI for high grade gliomas and FLAIR for low grade gliomas. Postoperative ischemia was defined as new, confluent diffusion restriction on postoperative DWI. Post-RT injury was investigated in patients who received RT after first surgery and had at least 6 months of follow-up (FU), and was defined as new or increasing contrast-enhancement that subsequently stabilized or decreased during FU. After manual delineation and non-linear registration to MNI stereotaxic space, all lesions were investigated with regard to size and location of pre-operative tumor, resection cavity, residual tumor and extent of resection (EOR). Voxel-based analysis (VBA) was performed with family-wise error correction for multiple comparisons. RESULTS Postoperative ischemia occurred in 93 of 144 cases and was associated with a larger EOR (P=0.02). Ischemic volume was correlated with a larger preoperative tumor volume (P=0.009) and resection volume (P=0.001). Post-RT injury was found in 25 of 67 analyzed cases and was associated with a larger residual tumor volume (P=0.021) and a smaller EOR (P=0.005). VBA showed an association of the occurrence of post-RT lesions with a cluster of preoperative tumor voxels in the left temporal lobe and clusters of residual tumor voxels in the left temporal and right frontal region. No association in volume or location was found between postoperative ischemia and post-RT lesions. CONCLUSION Adverse events of glioma treatment may be influenced by tumor and treatment volumes. In our population, a larger EOR was associated with the occurrence of postoperative ischemia, and larger tumor and resection volumes were correlated with the volume of ischemia. Additionally, the occurrence of post-RT injury was associated with a larger residual tumor and a smaller EOR, as well as a left temporal preoperative tumor location and a right frontal or left temporal residual tumor location. A thorough examination of spatial and volumetric characteristics of the tumor, treatment and subsequent complications can help elucidate the etiology and guide treatment decisions.

Abstract 2831: Enhanced efficacy of HDAC inhibitor panobinostat and ONC206 combined with radiation therapy against human glioblastoma cell lines without H3K27M mutation

Abstract Background: Glioblastoma multiforme (GBM) is the most common form of malignant brain tumor in adults. The prognosis of GBM is still poor despite first-line therapy, and the median overall survival (OS) is 12-15 months, while the 5-year survival does not exceed 5%. Despite aggressive initial treatment, most patients develop recurrent diseases. Novel drug combinations for malignant CNS tumors are under investigation. Panobinostat is a histone deacetylase inhibitor (HDACi) with antineoplastic and antiangiogenic effects in glioma, and we previously noted synergy with combination of panobinostat and imipridone ONC206. ONC206 is under clinical investigation for treating adult and pediatric brain tumor patients. We decided to investigate the triple combination of ONC206, Panobinostat and radiation against glioma cells. Materials & Methods: We investigated cell viability and drug synergies of ONC206 plus Panobinostat with or without radiation in 4 human GBM cell lines at 72 hours. Results: We identified synergy between impridone ONC206 and Panobinostat which improved with radiation therapy IC50 values of panobinostat and ONC206 against cell lines U138, U87, T98G & U251MG ranges from 29-85 nM & 0.8-1.2 μM, respectively. Synergies between ONC206 and Panobinostat were observed across cell lines with combination indices of <0.5 indicating strong synergy. When treating with 4GY radiation after 48 h, combination index improved. documenting enhanced tumor cell killing of human glioma cells. Conclusion: Our ongoing studies reveal synergy between ONC206, Panobinostat and radiation against GBM cell lines. The enhanced synergy with radiation provides an opportunity to develop a novel treatment combination for high grade glioma with a focus on recurrent GBM. Citation Format: Vida Tajiknia, Wafik El Deiry, Lanlan Zhou. Enhanced efficacy of HDAC inhibitor panobinostat and ONC206 combined with radiation therapy against human glioblastoma cell lines without H3K27M mutation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2831.

Expression, Significance, and Correlation of Histone Deacetylase 1/RE-1 Silencing Transcription Factor and Neuronal Markers in Glioma.

Inducing the differentiation of glioma cells into neuron-like cells may be an effective strategy to combat glioma. The histone deacetylase 1/RE-1 silencing transcription factor (HDAC1/REST) complex regulates the expression of multiple neuronal genes. In this study, we analyzed the presence and significance of this regulatory effect in glioma based on bioinformatics methods. The Human Protein Atlas database was used to obtain immunohistochemical staining images. The Gene Expression Profiling Interactive Analysis and Chinese Glioma Genome Atlas databases were used to analyze the expression of HDAC1/REST and neuronal markers in glioma, their effects on survival, and the association between HDAC1/REST and the expression of neuronal markers and stem cell markers. The differentially expressed genes between the high and low HDAC1/REST groups were explored. The Database for Annotation, Visualization and Integrated Discovery database was used for gene ontology and kyoto encyclopedia of genes and genomes pathway enrichment analysis. The results showed that the expression of HDAC1 and REST increased with the grade of glioma, while the expression of neuronal markers decreased with the grade of glioma. High expression of HDAC1/REST and low expression of neuronal markers were associated with poor prognosis. HDAC1/REST expression was negatively correlated with the expression of neuronal markers, and positively correlated with the expression of neural stem cell markers. The genes up-regulated in the high HDAC1/REST group were mainly related to extracellular matrix and inflammation, and the down-regulated genes were mainly related to synapsis. This study suggested that HDAC1/REST may be involved in maintaining the malignant phenotype of glioma cells and the stem cell status of glioma stem cells by inhibiting the expression of neuronal markers, which promote the progression of glioma.

Experimental Study on the Anti-tumor and Pro-apoptotic Effects of Paeonol in Human Gliomas

Background: Current studies have demonstrated the anti-cancer effects of paeonol in some tumors; however, its effect on gliomas remains unknown. Objectives: This study aimed to investigate the anti-tumor effect of paeonol in human glioma tissues and cells including its effect and connection with apoptosis and oxidative stress in gliomas. Methods: Cell Counting Kit-8 (CCK-8) was used to detect the antiproliferative effect of paeonol in human U251 glioma cells. Transwell and colony-forming assays were employed to assess the effect of paeonol on the ability of invasion and colony formation of U251 cells. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, total antioxidant capacity (T-AOC), and catalase activity (CAT) were measured to evaluate the effect of paeonol on oxidative stress in U251 cells. Quantitative real-time polymerase chain reaction (RT-q) PCR and western blot were utilized to detect caspase-3 expression levels. Terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) staining detected the effect of paeonol on U251 cell apoptosis. Results: Paeonol decreased cell viability, as well as the proliferation, invasion, and colony formation ability of U251 cells. Paeonol reduced MDA content and increased the activities of SOD, CAT, and T-AOC in U251 cells. Caspase-3 expression was lower in human glioma tissues than in normal tissues of the human brain. Paeonol promoted U251 cell apoptosis as revealed by TUNEL staining results and the significant up-regulation of caspase-3 expression in U251 cells. Conclusion: These results indicated that paeonol has anti-tumor and pro-apoptotic effects in gliomas via oxidative stress regulation and the caspase-3 pathway. Our study, therefore, provides new ideas for the clinical treatment of gliomas.

T cell exhaustion assessment algorism in tumor microenvironment predicted clinical outcomes and immunotherapy effects in glioma.

Despite the recent increase in the use of immune checkpoint blockade (ICB), no ICB medications have been approved or are undergoing large-scale clinical trials for glioma. T cells, the main mediators of adaptive immunity, are important components of the tumor immune microenvironment. Depletion of T cells in tumors plays a key role in assessing the sensitivity of patients to immunotherapy. In this study, the bioinformatics approach was applied to construct T cell depletion-related risk assessment to investigate the impact of T cell depletion on prognosis and ICB response in glioma patients. The Cancer Genome Atlas (TCGA) and GSE108474 glioma cohorts and IMvigor210 immunotherapy datasets were collected, including complete mRNA expression profiles and clinical information. We used cell lines to verify the gene expression and the R 3.6.3 tool and GraphPad for bioinformatics analysis and mapping. T cell depletion in glioma patients displayed significant heterogeneity. The T cell depletion-related prognostic model was developed based on seven prognostic genes (HSPB1, HOXD10, HOXA5, SEC61G, H19, ANXA2P2, HOXC10) in glioma. The overall survival of patients with a high TEXScore was significantly lower than that of patients with a low TEXScore. In addition, high TEXScore scores were followed by intense immune responses and a more complex tumor immune microenvironment. The "hot tumors" were predominantly enriched in the high-risk group, which patients expressed high levels of suppressive immune checkpoints, such as PD1, PD-L1, and TIM3. However, patients with a low TEXScore had a more significant clinical response to immunotherapy. In addition, HSPB1 expression was higher in the U251 cells than in the normal HEB cells. In conclusion, the TEXScore related to T cell exhaustion combined with other pathological profiles can effectively assess the clinical status of glioma patients. The TEXScore constructed in this study enables the effective assessment of the immunotherapy response of glioma patients and provides therapeutic possibilities.

Immunogenic cell death-related risk signature predicts prognosis and characterizes the tumour microenvironment in lower-grade glioma.

Lower-grade glioma (LGG) is a common malignant primary tumour in the central nervous system, and most patients eventually develop highly aggressive gliomas despite comprehensive traditional treatment. Tumour molecular subtypes and prognostic biomarkers play a crucial role in LGG diagnosis and treatment. Therefore, the identification of novel biomarkers in LGG patients is crucial for predicting the prognosis of glioma. Immunogenic cell death (ICD) is defined as regulated cell death that is sufficient to activate the adaptive immune response of immunocompetent hosts. The combination of ICD and immunotherapy might exert a greater and more persistent antitumour effect in gliomas. In our study, we explored the expression, function, and genetic alterations of 34 ICD-related genes. Using 12 ICD-related genes, including IL17RA, IL1R1, EIF2AK3, CD4, PRF1, CXCR3, CD8A, BAX, PDIA3, CASP8, MYD88, and CASP1, we constructed and validated an ICD-related risk signature via least absolute shrinkage and selection operator (LASSO) Cox regression analysis. All the information was obtained from public databases, including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and the Chinese Glioma Genome Atlas (CGGA) databases. Our results revealed that ICD-high risk groups have a poor prognosis and might be more sensitive to immune checkpoint blockade (ICB) immunotherapy. In addition, ICD-high risk groups were associated with 1p19q noncodeletion, higher WHO grade, wild type IDH, and an immunosuppressive tumour microenvironment. We verified the prognostic value of 12 ICD-related genes in TCGA and CGGA databases. Immunohistochemistry was performed to verify the expression of several ICD-related genes at the protein level. Our study provides a novel and comprehensive perspective to elucidate the underlying mechanisms of LGG prognosis and direction for future individualized cancer immunotherapy.

Inhibition of PTPN21 has antitumor effects in glioma by restraining the EGFR/PI3K/AKT pathway

Protein tyrosine phosphatase non-receptor type 21 (PTPN21) has been recognised as a new tumour-associated protein that is implicated in diverse tumours. However, the correlation between PTPN21 and glioma remains unaddressed. This investigation focused on the relevance of PTPN21 in glioma. The Cancer Genome Atlas (TCGA) analysis identified PTPN21 as being up-regulated in glioma tissue. The elevation of PTP21 in glioma was validated by evaluating clinical specimen. Kaplan-Meier plot analysis revealed that a high PTPN21 level predicted poor survival rate in glioma patient. Silencing of PTPN21 produced remarkable anticancer effects in glioma cells including proliferation inhibition, cell cycle arrest, metastasis suppression and enhanced chemosensitivity. Mechanistic studies uncovered that PTPN21 contributes to mediation of the phosphatidyl-inositole-3 kinase (PI3K)/AKT pathway via the regulation of epidermal growth factor receptor (EGFR). Restraint of EGFR diminished PTPN21 overexpression-induced promoting effect on PI3K/AKT pathway. Reactivation of AKT reversed PTPN21 silencing-evoked antitumor effect. The tumorigenic potential of PTPN21-silenced glioma cells in vivo was markedly compromised. In summary, this study demonstrates that silencing of PTPN21 produces remarkable anticancer effects in glioma by restraining the EGFR/PI3K/AKT pathway.

Ferroptosis in Glioma Immune Microenvironment: Opportunity and Challenge.

Glioma is the most common intracranial malignant tumor in adults and the 5-year survival rate of glioma patients is extremely poor, even in patients who received Stupp treatment after diagnosis and this forces us to explore more efficient clinical strategies. At this time, immunotherapy shows great potential in a variety of tumor clinical treatments, however, its clinical effect in glioma is limited because of tumor immune privilege which was induced by the glioma immunosuppressive microenvironment, so remodeling the immunosuppressive microenvironment is a practical way to eliminate glioma immunotherapy resistance. Recently, increasing studies have confirmed that ferroptosis, a new form of cell death, plays an important role in tumor progression and immune microenvironment and the crosstalk between ferroptosis and tumor immune microenvironment attracts much attention. This work summarizes the progress studies of ferroptosis in the glioma immune microenvironment.

Pseudogene RPL32P3 regulates the blood\u2013tumor barrier permeability via the YBX2/HNF4G axis

The existence of the blood–tumor barrier (BTB) severely hinders the transport of anti-tumor drugs to brain tumor tissues. Selectively opening BTB is of great significance to improve the chemotherapy effect of glioma. Pseudogenes have been recognized as important regulators in various biologic processes. In this study, we identified that ribosomal protein L32 pseudogene 3 (RPL32P3) was highly expressed in glioma-exposed endothelial cells (GECs). Knockdown of RPL32P3 decreased the expression of tight junction-related proteins (TJPs) and increased BTB permeability. Subsequent analysis of the underlying mechanism indicated that RPL32P3 recruited lysine methyltransferase 2 A (KMT2A) to the Y-box binding protein 2 (YBX2) promoter region and mediated H3K4me3 to promote YBX2 transcription. Highly expressed YBX2 bound and stabilized hepatocyte nuclear factor 4 gamma (HNF4G) mRNA. Highly expressed HNF4G directly bound to the promoters of TJPs ZO-1, occludin and claudin-5 to promote their transcriptional activities and regulated BTB permeability. The simultaneous knockdown of RPL32P3, YBX2, and HNF4G combined with doxorubicin (DOX) increased the apoptosis of glioma cells. In conclusion, the current study indicated that RPL32P3 knockdown increased BTB permeability through the YBX2/HNF4G pathway. These findings may provide new targets for the comprehensive treatment of glioma.

Effect of Eriodictyol on Retinoblastoma via the PI3K/Akt Pathway.

Retinoblastoma (RB) is one of the most common intraocular malignancies in children, which causes vision loss and even threatens life. Eriodictyol is a natural flavonoid with strong anticancer activity. Some studies have shown that eriodictyol exerts anticancer effects in glioma, colon cancer, and lung cancer; however, no studies have reported the anticancer effects of eriodictyol on RB. Therefore, the aim of this study was to investigate the anticancer activity of eriodictyol against the RB Y79 cell line and its potential mechanism of action. Interestingly, we found that eriodictyol inhibited the proliferation, migration, and invasion of Y79 cells in a dose-dependent manner and decreased the expression of MMP-2 and MMP-9 proteins in the cells. In addition, eriodictyol-induced apoptosis in Y79 cells was assessed by flow cytometry and immunoblotting. Here, our study revealed that eriodictyol dose dependently inhibited the activation of the PI3K/Akt signaling pathway. Notably, the effect of eriodictyol on RB apoptosis was reversed by a PI3K agonist 740 Y-P. In conclusion, our study shows that eriodictyol effectively inhibits proliferation, migration, and invasion and induces apoptosis in RB cell lines, which may be the result of blocking the PI3K/Akt signaling pathway. Thus, eriodictyol may provide a new theoretical basis for exploring targeted antitumor natural therapies.

Research Progress on Circular RNA in Glioma.

The discovery of circular RNA (circRNA) greatly complements the traditional gene expression theory. CircRNA is a class of non-coding RNA with a stable cyclic structure. They are highly expressed, spatiotemporal-specific and conservative across species. Importantly, circRNA participates in the occurrence of many kinds of tumors and regulates the tumor development. Glioma is featured by limited therapy and grim prognosis. Cancer-associated circRNA compromises original function or creates new effects in glioma, thus contributing to oncogenesis. Therefore, this article reviews the biogenesis, metabolism, functions and properties of circRNA as a novel potential biomarker for gliomas. We elaborate the expression characteristics, interaction between circRNA and other molecules, aiming to identify new targets for early diagnosis and treatment of gliomas.

Fraxetin exerts anticancer effect in glioma by suppressing MiR-21-3p.

Fraxetin (FXT) exerts anticancer function in multiple cancers, but its function on glioma was ill-defined. This article expounded the mechanism by which FXT exerts an anticancer effect in glioma. The effect of gradient concentration of FXT on the viability of glioma cell lines was determined by cell counting kit 8. Effects of FXT on proliferation, apoptosis, and cell cycle in glioma cell lines were determined by colony formation assay, flow cytometry, and Hoechst 33342 staining. Expressions of apoptosis-related gene, cycle-related gene, and glioma-related miRNAs after FXT (25 and 50 μmol/L) treatment were determined by quantitative reverse transcription polymerase chain reaction and western blot as needed. After miR-21-3p overexpression, cell viability and apoptosis of glioma cell lines treated with FXT (50 μmol/L) were tested again. Although 1μmol/L FXT had no significant effect on cell viability, 5, 10, 25, and 50 μmol/L FXT suppressed cell viability in a concentration-dependent manner. FXT inhibited proliferation, promoted apoptosis, and induced cell cycle arrest in G0/G1 phase in glioma cell lines. These effects may be achieved by elevated expressions of Bax and cleaved caspase-3 and diminished expressions of Bcl-2, Bcl-XL, cyclin E1, cyclin D1, and cyclin-dependent kinase-6. FXT attenuated the contents of miR-21-3p and miR-455-3p, and escalated the contents of miR-124-3p and miR-7-5p. The regulation of FXT on cell viability, proliferation and apoptosis was reversed by miR-21-3p overexpression. FXT suppressed the development of glioma cells by downregulating miR-21-3p.

Localized blood–brain barrier opening in infiltrating gliomas with MRI-guided acoustic emissions–controlled focused ultrasound

Pharmacological treatment of gliomas and other brain-infiltrating tumors remains challenging due to limited delivery of most therapeutics across the blood-brain barrier (BBB). Transcranial MRI-guided focused ultrasound (FUS), an emerging technology for noninvasive brain treatments, enables transient opening of the BBB through acoustic activation of circulating microbubbles. Here, we evaluate the safety and utility of transcranial microbubble-enhanced FUS (MB-FUS) for spatially targeted BBB opening in patients with infiltrating gliomas. In this Phase 0 clinical trial (NCT03322813), we conducted comparative and quantitative analyses of FUS exposures (sonications) and their effects on gliomas using MRI, histopathology, microbubble acoustic emissions (harmonic dose [HD]), and fluorescence-guided surgery metrics. Contrast-enhanced MRI and histopathology indicated safe and reproducible BBB opening in all patients. These observations occurred using a power cycling closed feedback loop controller, with the power varying by nearly an order of magnitude on average. This range underscores the need for monitoring and titrating the exposure on a patient-by-patient basis. We found a positive correlation between microbubble acoustic emissions (HD) and MR-evident BBB opening (P = 0.07) and associated interstitial changes (P < 0.01), demonstrating the unique capability to titrate the MB-FUS effects in gliomas. Importantly, we identified a 2.2-fold increase of fluorescein accumulation in MB-FUS-treated compared to untreated nonenhancing tumor tissues (P < 0.01) while accounting for vascular density. Collectively, this study demonstrates the capabilities of MB-FUS for safe, localized, controlled BBB opening and highlights the potential of this technology to improve the surgical and pharmacologic treatment of brain tumors.

Sevoflurane impedes glioma progression via regulating circ_0000215/miR-1200/NCR3LG1 axis.

Sevoflurane has been reported to have anti-tumorigenic effects in glioma. Circ_0000215 was found to play vital functions in the pathological progressions of glioma. However, whether circ_0000215 mediates the inhibitory effects of sevoflurane on glioma cells remains unclear. In vitro assays were performed using cell counting kit-8, flow cytometry, transwell and Western blot assays. The expression levels of circ_0000215, microRNA (miR)-1200 and NCR3LG1 (Natural Killer Cell Cytotoxicity Receptor 3 Ligand 1) were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and/or Western blot. The dual-luciferase reporter assay and pull-down assay were used to investigate the relationship between miR-1200 and circ_0000215 or NCR3LG1. In vivo assay was conducted using xenograft nude mice model. In vitro assays suggested that sevoflurane repressed glioma cell proliferation, metastasis and induced apoptosis as well as hindered tumor growth in vivo, which were reversed by circ_0000215 overexpression. Mechanically, circ_0000215 was confirmed to directly target miR-1200, and NCR3LG1 was a target of miR-1200 in glioma cells. Importantly, circ_0000215 could regulate NCR3LG1 expression via miR-1200. Besides that, rescue assay suggested that circ_0000215 attenuated the inhibitory effects of sevoflurane on glioma cell growth and metastasis, which were reversed by miR-1200 overexpression or NCR3LG1 knockdown. Our study revealed that sevoflurane could suppress glioma tumorigenesis by regulating circ_0000215/miR-1200/NCR3LG1 axis, suggesting a new insight into the therapeutic potential of sevoflurane in glioma treatment.

SLIT2/ROBO signaling in tumor-associated microglia and macrophages drives glioblastoma immunosuppression and vascular dysmorphia.

SLIT2 is a secreted polypeptide that guides migration of cells expressing Roundabout 1 and 2 (ROBO1 and ROBO2) receptors. Herein, we investigated SLIT2/ROBO signaling effects in gliomas. In patients with glioblastoma (GBM), SLIT2 expression increased with malignant progression and correlated with poor survival and immunosuppression. Knockdown of SLIT2 in mouse glioma cells and patient-derived GBM xenografts reduced tumor growth and rendered tumors sensitive to immunotherapy. Tumor cell SLIT2 knockdown inhibited macrophage invasion and promoted a cytotoxic gene expression profile, which improved tumor vessel function and enhanced efficacy of chemotherapy and immunotherapy. Mechanistically, SLIT2 promoted microglia/macrophage chemotaxis and tumor-supportive polarization via ROBO1- and ROBO2-mediated PI3K-γ activation. Macrophage Robo1 and Robo2 deletion and systemic SLIT2 trap delivery mimicked SLIT2 knockdown effects on tumor growth and the tumor microenvironment (TME), revealing SLIT2 signaling through macrophage ROBOs as a potentially novel regulator of the GBM microenvironment and immunotherapeutic target for brain tumors.

The Neurogenic Compound P7C3 Regulates the Aerobic Glycolysis by Targeting Phosphoglycerate Kinase 1 in Glioma.

BackgroundP7C3 is a neurogenic compound that exhibits neuroprotective properties in neural cells. However, its target proteins and effects in glioma are unknown.MethodsThe candidate P7C3 target proteins were analyzed using a human protein microarray containing 23136 human proteins. A streptavidin agarose affinity assay was used to verify the direct interaction between P7C3 and phosphoglycerate kinase 1 (PGK1). Mass spectrometry was used to identify the binding sites of PGK1 for P7C3 binding. Seahorse XF96 extracellular flux analyzer was used to measure the cell oxygen consumption rate and extracellular acidification rate. Glycolytic metabolites were measured using the related kits. Protein level was detected by western blotting and immunohistochemical staining. Autophagy was analyzed using a transmission electron microscope and western blotting. The malignancy of tumor progression in vitro and in vivo was analyzed based on cell viability, apoptosis and proliferation, migration and invasion, and xenograft model. Glial cells were marked by antibodies via immunohistochemical staining.ResultsThe human protein microarray identified 577 candidate P7C3 target proteins. The global profile of P7C3 target proteins indicated that P7C3 regulates glycolysis. Metabolic experiments confirmed that P7C3 regulates aerobic glycolysis in glioma cells. The underlying mechanism of P7C3 was found to be direct targeting PGK1 at lysine residues and asparagine residues, and the specific P7C3-PGK1 interaction led to decreased protein level and total intracellular kinase activity of PGK1. The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases indicated that the mRNA level of PGK1 is significantly increased in high-grade glioma, and the abnormally high mRNA level of PGK1 is associated with a poor prognosis in patients with glioma, suggesting that PGK1 is a promising target for glioma therapy. The inhibition of PGK1 and the subsequent suppression of aerobic glycolysis caused by P7C3 inhibited the malignant growth of glioma in vitro and in vivo. Furthermore, P7C3 did not damage normal glial cells under concentration, which exhibit an inhibitory effect on gliomas.ConclusionsThis study revealed that P7C3 suppresses glioma by regulating aerobic glycolysis via directly targeting PGK1. Furthermore, we identified the P7C3 target proteins for the first time which is expected to provide scientific clues for future studies.

Long non-coding RNA STARD13-AS suppresses glioma cell biological activities by vitro study

IntroductionIt has been unclear whether STARD13-AS has effects in glioma. The aim of our research was to investigate the effects of STARD13-AS in glioma development and the mechanisms underlying these effects.Material and methodsAdjacent normal and tumor tissues were collected for long non-coding RNA (lncRNA) microarray screening. STARD13-AS expression was measured by in situ hybridization (ISH) and reverse-transcription quantitative PCR (RT-qPCR) assays, and correlations between STARD13-AS and clinicopathological parameters and prognosis were analyzed. STARD13-AS transfection of glioma cell lines (U251 and U87) was used to evaluate biological activities of cells. Western blotting (WB) and RT-qPCR assays were used to investigate the underlying mechanisms.ResultsAccording to lncRNA microarray screening, ISH, and RT-qPCR, lncRNA STARD13-AS was significantly downregulated in tumor tissues. Low STARD13-AS expression was strongly correlated with poor prognosis and malignant clinicopathology. After STARD13-AS transfection, biological activities of glioma cells were significantly decreased (p &lt; 0.001 for both cell types). WB and RT-qPCR assays showed that protein and mRNA expression levels of cyclin D, cyclin E, N-cadherin, E-cadherin, and vimentin were significantly related to STARD13-AS overexpression (p &lt; 0.001 in all cases).ConclusionsSTARD13-AS overexpression suppresses the biological activities of glioma cells, indicating that STARD13-AS is a potential target for glioma treatment.