Deep-targeted gene sequencing reveals ARID1A mutation as an important driver of glioblastoma.

AIMS: To investigate the key factors influencing glioma progression and the emergence of treatment resistance by examining the intrinsic connection between mutations in DNA damage and repair-related genes and the development of chemoresistance in gliomas. METHODS: We conducted a comprehensive analysis of deep-targeted gene sequencing data from 228 glioma samples. This involved identifying differentially mutated genes across various glioma grades, assessing their functions, and employing I-TASSER for homology modeling. We elucidated the functional changes induced by high-frequency site mutations in these genes and investigated their impact on glioma progression. RESULTS: The analysis of sequencing mutation results of deep targeted genes in integration revealed that ARID1A gene mutation occurs frequently in glioblastoma and alteration of ARID1A could affect the tolerance of glioma cells to temozolomide treatment. The deletion of proline at position 16 in the ARID1A protein affected the stability of binding of the SWI/SNF core subunit BRG1, which in turn affected the stability of the SWI/SNF complex and led to altered histone modifications in the CDKN1A promoter region, thereby affecting the biological activity of glioma cells, as inferred from modeling and protein interaction analysis. CONCLUSION: The ARID1A gene is a critical predictive biomarker for glioma. Mutations at the ARID1A locus alter the stability of the SWI/SNF complex, leading to changes in transcriptional regulation in glioma cells. This contributes to an increased malignant phenotype of GBM and plays a pivotal role in mediating chemoresistance.

Reduced Graphene Oxide Coating LiFePO4 Composite Cathodes for Advanced Lithium-Ion Battery Applications.

Recently, the application of LiFePO4 (LFP) batteries in electric vehicles has attracted extensive attention from researchers. This work presents a composite of LFP particles trapped in reduced graphene oxide (rGO) nanosheets obtained through the high-temperature reduction strategy. The obtained LiFePO4/rGO composites indicate spherical morphology and uniform particles. As to the structure mode of the composite, LFP distributes in the interlayer structure of rGO, and the rGO evenly covers the surface of the particles. The LFP/rGO cathodes demonstrate a reversible specific capacity of 165 mA h g-1 and high coulombic efficiency at 0.2 C, excellent rate capacity (up to 10 C), outstanding long-term cycling stability (98%) after 1000 cycles at 5 C. The combined high electron conductivity of the layered rGO coating and uniform LFP particles contribute to the remarkable electrochemical performance of the LFP/rGO composite. The unique LFP/rGO cathode provides a potential application in high-power lithium-ion batteries.

Blockage of EGFR/AKT and mevalonate pathways synergize the antitumor effect of temozolomide by reprogramming energy metabolism in glioblastoma.

BACKGROUND: Metabolism reprogramming plays a vital role in glioblastoma (GBM) progression and recurrence by producing enough energy for highly proliferating tumor cells. In addition, metabolic reprogramming is crucial for tumor growth and immune-escape mechanisms. Epidermal growth factor receptor (EGFR) amplification and EGFR-vIII mutation are often detected in GBM cells, contributing to the malignant behavior. This study aimed to investigate the functional role of the EGFR pathway on fatty acid metabolism remodeling and energy generation. METHODS: Clinical GBM specimens were selected for single-cell RNA sequencing and untargeted metabolomics analysis. A metabolism-associated RTK-fatty acid-gene signature was constructed and verified. MK-2206 and MK-803 were utilized to block the RTK pathway and mevalonate pathway induced abnormal metabolism. Energy metabolism in GBM with activated EGFR pathway was monitored. The antitumor effect of Osimertinib and Atorvastatin assisted by temozolomide (TMZ) was analyzed by an intracranial tumor model in vivo. RESULTS: GBM with high EGFR expression had characteristics of lipid remodeling and maintaining high cholesterol levels, supported by the single-cell RNA sequencing and metabolomics of clinical GBM samples. Inhibition of the EGFR/AKT and mevalonate pathways could remodel energy metabolism by repressing the tricarboxylic acid cycle and modulating ATP production. Mechanistically, the EGFR/AKT pathway upregulated the expressions of acyl-CoA synthetase short-chain family member 3 (ACSS3), acyl-CoA synthetase long-chain family member 3 (ACSL3), and long-chain fatty acid elongation-related gene ELOVL fatty acid elongase 2 (ELOVL2) in an NF-κB-dependent manner. Moreover, inhibition of the mevalonate pathway reduced the EGFR level on the cell membranes, thereby affecting the signal transduction of the EGFR/AKT pathway. Therefore, targeting the EGFR/AKT and mevalonate pathways enhanced the antitumor effect of TMZ in GBM cells and animal models. CONCLUSIONS: Our findings not only uncovered the mechanism of metabolic reprogramming in EGFR-activated GBM but also provided a combinatorial therapeutic strategy for clinical GBM management.

Identification of miRNAs Involved in Intracranial Aneurysm Rupture in Cigarette-Smoking Patients.

INTRODUCTION: Smoking is an independent risk factor for the formation and rupture of intracranial aneurysms (IA). However, the underlying mechanism remains unclear. METHODS: In this study, we performed miRNA sequencing on plasma from 10 smoking patients with IA, 10 non-smoking patients with IA, and 10 healthy controls. The differentially expressed miRNAs (DE miRNAs) between smoking and non-smoking patients with IA were identified. Functional and pathway enrichment analysis is employed to investigate the potential functions of those DE miRNA target genes. The correlations with the clinical parameters were assessed using receiver operating characteristic curve (ROC) analysis. RESULTS: In total, we identified 428 DE miRNAs. Functional enrichment analysis showed the target genes were significantly enriched in biological aspects related to cell characteristics, such as cell cycle, cell differentiation, and cell migration. Pathway analysis showed DE miRNAs mainly enriched in the PI3K-Akt signaling pathway, Focal adhesion, and JAK-STAT signaling pathway. The expressions of miR-574-5p, miR-151a-3p, and miR-652-3p correlated well with aneurysm parameters. The AUC of miR-574-5p, miR-151a-3p, and miR-652-3p were 97%, 92%, and 99%, respectively. CONCLUSION: Our study indicated that smoking significantly altered the plasma miRNA profile in patients with IA. The expression of miR-574-5p, miR-151a-3p, and miR-652-3p correlated with aneurysm parameters, which may play a significant role in the formation and rupture of IA.

Radionecrosis mimicking pseudo­progression in a patient with lung cancer and brain metastasis following the combination of anti­PD­1 therapy and stereotactic radiosurgery: A case report.

Brain metastases (BMs) usually develop in patients with non-small cell lung cancer. In addition to systemic therapy, radiation therapy and surgery, anti-programmed cell death-ligand 1 (PD-L1) therapy is another promising clinical anticancer treatment modality. However, the optimal timing and drug-drug interactions of anti-PD-L1 therapy with other combined treatments remain to be elucidated. Treatment with anti-PD-L1 therapy is associated with an increased risk of radionecrosis (RN) regardless of tumor histology. The present study described a case of RN in a patient with lung adenocarcinoma and with BM who received anti-PD-L1 therapy. Before anti-PD-L1 treatment, the patient received whole brain radiotherapy. During durvalumab treatment, the intracranial metastases regressed. The progression of intracranial lesions 9 months later prompted a second-line of therapy with PD-L1 inhibitor durvalumab and stereotactic radiotherapy (SRT). Despite stereotactic irradiation, the lesions progressed further, leading to surgical resection. On examination, RN was detected, but there was no evidence of metastatic lung cancer. The aim of the present study was to present the longitudinal change in magnetic resonance imaging in RN following STR and anti-PD-L1 combined therapy. The atypical image of RN is conditionally important for making an accurate preoperative diagnosis.

Development of glioblastoma organoids and their applications in personalized therapy.

Glioblastomas (GBMs) are the brain tumors with the highest malignancy and poorest prognoses. GBM is characterized by high heterogeneity and resistance to drug treatment. Organoids are 3-dimensional cultures that are constructed in vitro and comprise cell types highly similar to those in organs or tissues in vivo, thus simulating specific structures and physiological functions of organs. Organoids have been technically developed into an advanced ex vivo disease model used in basic and preclinical research on tumors. Brain organoids, which simulate the brain microenvironment while preserving tumor heterogeneity, have been used to predict patients' therapeutic responses to antitumor drugs, thus enabling a breakthrough in glioma research. GBM organoids provide an effective supplementary model that reflects human tumors' biological characteristics and functions in vitro more directly and accurately than traditional experimental models. Therefore, GBM organoids are widely applicable in disease mechanism research, drug development and screening, and glioma precision treatments. This review focuses on the development of various GBM organoid models and their applications in identifying new individualized therapies against drug-resistant GBM.

EPIC-0307-mediated selective disruption of PRADX-EZH2 interaction and enhancement of temozolomide sensitivity to glioblastoma via inhibiting DNA repair and MGMT.

BACKGROUND: Temozolomide (TMZ) treatment efficacy in glioblastoma (GBM) has been limited by resistance. The level of O-6-methylguanine-DNA methyltransferase (MGMT) and intrinsic DNA damage repair factors are important for the TMZ response in patients. Here, we reported a novel compound, called EPIC-0307, that increased TMZ sensitivity by inhibiting specific DNA damage repair proteins and MGMT expression. METHODS: EPIC-0307 was derived by molecular docking screening. RNA immunoprecipitation (RIP), and chromatin immunoprecipitation by RNA (ChIRP) assays were used to verify the blocking effect. Chromatin immunoprecipitation (ChIP) and co-immunoprecipitation (Co-IP) assays were performed to explore the mechanism of EPIC-0307. A series of in vivo and in vitro experiments were designed to evaluate the efficacy of EPIC-0307 in sensitizing GBM cells to TMZ. RESULTS: EPIC-0307 selectively disrupted the binding of PRADX to EZH2 and upregulated the expression of P21 and PUMA, leading to cell cycle arrest and apoptosis in GBM cells. EPIC-0307 exhibited a synergistic inhibitory effect on GBM when combined with TMZ by downregulating TMZ-induced DNA damage repair responses and epigenetically silencing MGMT expression through modulating the recruitment of ATF3-pSTAT3-HDAC1 regulatory complex to the MGMT promoter. EPIC-0307 demonstrated significant efficacy in suppressing the tumorigenesis of GBM cells, restoring TMZ sensitivity. CONCLUSION: This study identified a potential small-molecule inhibitor (SMI) EPIC-0307 that selectively disrupted the PRADX-EZH2 interaction to upregulate expressions of tumor suppressor genes, thereby exerting its antitumor effects on GBM cells. EPIC-0307 treatment also increased the chemotherapeutic efficacy of TMZ by epigenetically downregulating DNA repair-associate genes and MGMT expression in GBM cells.

The diagnostic significance of cerebrospinal fluid cytology and circulating tumor DNA in meningeal carcinomatosis.

Objective: The objective of this research is to investigate the clinical application value of cerebrospinal fluid (CSF) cytology and circulating tumor DNA (ctDNA) in lung adenocarcinoma (LUAD) meningeal metastasis-meningeal carcinomatosis (MC), and to further explore the possible molecular mechanisms and drug treatment targets of LUAD meningeal metastasis by next-generation sequencing (NGS). Methods: We retrospectively analyzed LUAD with MC in 52 patients. CSF cytology was carried out using the slide centrifugation precipitation method and May-Grüwald-Giemsa (MGG) staining. Tumor tissue, plasma and CSF ctDNA of some MC patients were detected by NGS. Results: Of the 52 MC patients, 46 (88.46%) were positive for CSF cytology and 34 (65.38%) were positive for imaging, with statistically significant differences in diagnostic positivity (P < 0.05). In 32 of these patients, CSF cytology, cerebrospinal fluid ctDNA, plasma ctDNA and MRI examination were performed simultaneously, and the positive rates were 84.38, 100, 56.25, and 62.50% respectively, the difference was statistically significant (P < 0.001). Analysis of the NGS profiles of tumor tissues, plasma and CSF of 12 MC patients: the mutated gene with the highest detection rate was epidermal growth factor receptor (EGFR) and the detection rate were 100, 58.33, and 100% respectively in tumor tissues, plasma and CSF, and there were 6 cases of concordance between plasma and tissue EGFR mutation sites, with a concordance rate of 50.00%, and 12 cases of concordance between CSF and tissue EGFR mutation sites, with a concordance rate of 100%. In addition, mutations not found in tissue or plasma were detected in CSF: FH mutation, SETD2 mutation, WT1 mutation, CDKN2A mutation, CDKN2B mutation, and multiple copy number variants (CNV), with the most detected being CDKN2A mutation and MET amplification. Conclusion: CSF cytology is more sensitive than traditional imaging in the diagnosis of meningeal carcinomatosis and has significant advantages in the early screening and diagnosis of MC patients. CSF ctDNA can be used as a complementary diagnostic method to negative results of CSF cytology and MRI, and CSF ctDNA can be used as an important method for liquid biopsy of patients with MC, which has important clinical significance in revealing the possible molecular mechanisms and drug treatment targets of meningeal metastasis of LUAD.

Separable Microneedles with Photosynthesis-Driven Oxygen Manufactory for Diabetic Wound Healing.

Oxygen plays an important role in diabetic chronic wound healing by regulating various life activities such as cell proliferation, migration, and angiogenesis. Therefore, oxygen-delivering systems have drawn much attention and evolved continuously. Here, we propose that an active Chlorella vulgaris (Cv)-loaded separable microneedle (MN) can be used to control oxygen delivery, which then promotes wound healing. The Cv-loaded microneedles (CvMN) consist of a polyvinyl acetate (PVA) substrate and gelatin methacryloyl (GelMA) tips with encapsulated Cv. Once CvMN is applied to diabetic wound, the PVA basal layer is rapidly dissolved in a short time, while the noncytotoxic and biocompatible GelMA tips remain in the skin. By taking advantage of the photosynthesis of Cv, oxygen would be continuously produced in a green way and released from CvMN in a controlled manner. Both in vitro and in vivo results showed that CvMN could promote cell proliferation, migration, and angiogenesis and enhance wound healing in diabetic mice effectively. The remarkable therapeutic effect is mainly attributed to the continuous generation of dissolved oxygen in CvMN and the presence of antioxidant vitamins, γ-linolenic acid, and linoleic acid in Cv. Thus, CvMN provides a promising strategy for diabetic wound healing with more possibility of clinical transformations.

Temporal and spatial stability of the EM/PM molecular subtypes in adult diffuse glioma.

Detailed characterizations of genomic alterations have not identified subtype-specific vulnerabilities in adult gliomas. Mapping gliomas into developmental programs may uncover new vulnerabilities that are not strictly related to genomic alterations. After identifying conserved gene modules co-expressed with EGFR or PDGFRA (EM or PM), we recently proposed an EM/PM classification scheme for adult gliomas in a histological subtype- and grade-independent manner. By using cohorts of bulk samples, paired primary and recurrent samples, multi-region samples from the same glioma, single-cell RNA-seq samples, and clinical samples, we here demonstrate the temporal and spatial stability of the EM and PM subtypes. The EM and PM subtypes, which progress in a subtype-specific mode, are robustly maintained in paired longitudinal samples. Elevated activities of cell proliferation, genomic instability and microenvironment, rather than subtype switching, mark recurrent gliomas. Within individual gliomas, the EM/PM subtype was preserved across regions and single cells. Malignant cells in the EM and PM gliomas were correlated to neural stem cell and oligodendrocyte progenitor cell compartment, respectively. Thus, while genetic makeup may change during progression and/or within different tumor areas, adult gliomas evolve within a neurodevelopmental framework of the EM and PM molecular subtypes. The dysregulated developmental pathways embedded in these molecular subtypes may contain subtype-specific vulnerabilities.

A novel compound EPIC-0412 reverses temozolomide resistance via inhibiting DNA repair/MGMT in glioblastoma.

BACKGROUND: Temozolomide (TMZ) resistance has become an important obstacle affecting its therapeutic benefits. O6-methylguanine DNA methyltransferase (MGMT) is primarily responsible for the TMZ resistance in Glioblastoma multiforme (GBM) patients. In addition, active DNA damage repair pathways can also lead to TMZ resistance. Here, we reported a novel small-molecule inhibitor EPIC-0412 that improved the therapeutic efficacy of TMZ by inhibiting the DNA damage repair pathway and MGMT in GBM via epigenetic pathways. METHODS: The small-molecule compound EPIC-0412 was obtained through high-throughput screening. RNA immunoprecipitation (RIP), chromatin isolation by RNA purification (ChIRP), and chromatin immunoprecipitation (ChIP) assays were used to verify the effect of EPIC-0412. Co-immunoprecipitation (Co-IP) was used to elucidate the interactions of transcription factors at the MGMT promoter region. Animal experiments using a mouse model were performed to verify the efficacy of EPIC-0412 in sensitizing GBM cells to TMZ. RESULTS: EPIC-0412 physically interrupts the binding of HOTAIR and EZH2, leading to the upregulation of CDKN1A and BBC3, causing cell cycle arrest and apoptosis in GBM cells. EPIC-0412 inhibits DNA damage response in GBM cells through the p21-E2F1 DNA damage repair axis. EPIC-0412 epigenetically silences MGMT through its interaction with the ATF3-p-p65-HADC1 axis at the MGMT promoter region. The application of EPIC-0412 restored the TMZ sensitivity in GBM in vivo experiments. CONCLUSION: This study discovered a small-molecule inhibitor EPIC-0412, which enhanced the chemotherapeutic effect of TMZ by acting on the p21-E2F1 DNA damage repair axis and ATF3-p-p65-MGMT axis, providing evidence for combining epigenetic drugs to increase the sensitization toward TMZ in GBM patients.

Anti-Tr/DNER antibody-associated cerebellar ataxia: three rare cases report and literature review.

BACKGROUND: To report three cases of autoimmune cerebellar ataxia related to anti-delta/notch-like epidermal growth factor-related receptor (Tr/DNER) antibodies. CASE PRESENTATION: Patients with unknown cerebellar ataxia were screened with autoimmune cerebellar ataxia (ACA)-related antibody panel. The anti-Tr antibody was positive in three female patients in whom the onset ages were 43 years, 35 years and 43 years old. The antibody titres of serum and cerebrospinal fluid were all 1:32. Cerebral ataxia was the most prominent presentation. Mild cerebellar atrophy was found in one of the patients. Immunotherapy was effective in all three patients. CONCLUSION: The Tr antibody is associated with autoimmune ataxia, and it has been suggested that the anti-Tr antibody should be tested in patients with cerebellar ataxia who are negative for routine ACA antibodies. Early immunotherapy may improve patient prognoses.

Identification of key genes of anti-programmed death ligand 1 for meningioma immunotherapy by bioinformatic analysis.

Meningioma is one of the most common primary tumors in the central nervous system (CNS). A deeper understanding of its molecular characterization could provide potential therapeutic targets to reduce recurrence. In this study, we attempted to identify specific gene mutations in meningioma for immunotherapy. One GSE43290 dataset was obtained from the Gene Expression Omnibus (GEO) database to find differentially expressed genes (DEGs) between meningioma tissues and normal meninges. In total, 420 DEGs were identified, including 15 up-regulated and 405 down-regulated genes. Functional enrichment analysis showed that these DEGs were mainly enriched in PI3K-Akt signaling pathway, Focal adhesion, and MAPK signaling pathway. We identified 20 hub genes by protein-protein interaction (PPI) analysis. Among the hub genes, the expression of FLT1, CXCL8, JUN, THBS1, FECAM1, CD34, and FGF13 were negatively correlated with Programmed Death Ligand-1 (PD-L1). Additionally, the expression of those genes was co-regulated by miR-155-5p. The findings suggest that miR-155-5p play an important role in the pathogenesis of meningioma and may represent potential therapeutic targets for its anti-PD-L1 immunotherapy.

Origin, activation, and targeted therapy of glioma-associated macrophages.

The glioma tumor microenvironment plays a crucial role in the development, occurrence, and treatment of gliomas. Glioma-associated macrophages (GAMs) are the most widely infiltrated immune cells in the tumor microenvironment (TME) and one of the major cell populations that exert immune functions. GAMs typically originate from two cell types-brain-resident microglia (BRM) and bone marrow-derived monocytes (BMDM), depending on a variety of cytokines for recruitment and activation. GAMs mainly contain two functionally and morphologically distinct activation types- classically activated M1 macrophages (antitumor/immunostimulatory) and alternatively activated M2 macrophages (protumor/immunosuppressive). GAMs have been shown to affect multiple biological functions of gliomas, including promoting tumor growth and invasion, angiogenesis, energy metabolism, and treatment resistance. Both M1 and M2 macrophages are highly plastic and can polarize or interconvert under various malignant conditions. As the relationship between GAMs and gliomas has become more apparent, GAMs have long been one of the promising targets for glioma therapy, and many studies have demonstrated the therapeutic potential of this target. Here, we review the origin and activation of GAMs in gliomas, how they regulate tumor development and response to therapies, and current glioma therapeutic strategies targeting GAMs.

TCA-phospholipid-glycolysis targeted triple therapy effectively suppresses ATP production and tumor growth in glioblastoma.

Rationale: Glioblastoma (GBM) displays a complex metabolic reprogramming in cancer cells. Adenosine triphosphate (ATP) is one of the central mediators of cell metabolism and signaling. GBM cells generate ATP by glycolysis and the tricarboxylic acid (TCA) cycle associated with oxidative phosphorylation (OXPHOS) through the breaking-down of pyruvate or fatty acids to meet the growing energy demand of cancer cells. Therefore, it's urgent to develop novel treatments targeting energy metabolism to hinder tumor cell proliferation in GBM. Methods: Non-targeted metabolomic profiling analysis was utilized to evaluate cell metabolic reprogramming using a small molecule inhibitor (SMI) EPIC-0412 treatment. Cellular oxygen consumption rate (OCR) and the total proton efflux rate (PER), as well as ATP concentration, were tracked to study metabolic responses to specifically targeted inhibitors, including EPIC-0412, arachidonyl trifluoromethyl ketone (AACOCF3), and 2 deoxy-D-glucose (2-DG). Cancer cell proliferation was assessed by CCK-8 measurements and colony formation assay. Additionally, flow cytometry, immunoblotting (IB), and immunofluorescence (IF) analyses were performed with GBM cells to understand their tumorigenic properties under treatments. Finally, the anticancer effects of this combination therapy were evaluated in the GBM mouse model by convection-enhanced delivery (CED). Results: We found that SMI EPIC-0412 could effectively perturb the TCA cycle, which participated in the combination therapy of cytosolic phospholipase A2 (cPLA2)-inhibitor AACOCF3, and hexokinase II (HK2)-inhibitor 2-DG to disrupt the GBM energy metabolism for targeted metabolic treatments. ATP production was significantly declined in glioma cells when treated with monotherapy (EPIC-0412 or AACOCF3), dual therapy (EPIC-0412 + AACOCF3), or triple therapy (EPIC-0412 + AACOCF3 +2-DG) regimen. Our experiments revealed that these therapies hindered glioma cell proliferation and growth, leading to the reduction in ATP production and G0/G1 cell cycle arrest. We demonstrated that the combination therapy effectively extended the survival of cerebral tumor-bearing mice. Conclusion: Our findings indicate that the TCA-phospholipid-glycolysis metabolism axis can be blocked by specific inhibitors that significantly disrupt the tumor energy metabolism and suppress tumor proliferation in vitro and in vivo, suggesting that targeting ATP synthesis inhibition in cancer cells might be an attractive therapeutic avenue in GBM management.

PTRF/Cavin-1 enhances chemo-resistance and promotes temozolomide efflux through extracellular vesicles in glioblastoma.

Background: The concentration and duration of intracellular drugs have always been the key factors for determining the efficacy of the treatment. Efflux of chemotherapeutic drugs or anticancer agents is a major reason for multidrug resistance generation in cancer cells. The high expression of polymerase I and transcript release factor (PTRF) is correlated with a worse prognosis in glioma patients. However, the importance of PTRF on temozolomide (TMZ) resistance in glioblastoma (GBM) is poorly understood. Methods: TCGA data analysis, CGGA data analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), clone formation, cell counting kit-8 (cck-8), western blot (WB), immunofluorescence (IF), immunohistochemistry (IHC) and flow cytometry assays were performed to investigate the underlying mechanism and effect of PTRF on TMZ-resistance in a variety of GBM cell lines and GBM patient-derived xenograft (PDX) models. Clone formation, WB, IF, IHC and flow cytometry assays were performed to examine the efficacy of sequential therapy of TMZ followed by CQ in GBM cells and PDX models. Results: The prognosis of GBM patients treated with TMZ was negatively correlated with PTRF expression. Our results reveal that PTRF knockdown significantly decrease proliferation and increase apoptosis in GBM after TMZ treatment. Moreover, PTRF contribute to TMZ-resistance by increasing TMZ efflux through extracellular vesicles (EVs). Furthermore, our results demonstrate that sequential therapy of TMZ followed by CQ significantly promotes the TMZ efficacy against GBM by increasing intracellular TMZ concentration ([TMZ]i). Conclusion: This study highlights that PTRF can act as an independent biomarker to predict the prognosis of GBM patients after TMZ treatment and describes a new mechanism contributing to TMZ-resistance. In addition, this study may provide a novel idea for GBM therapy.

Neuronal STAT3/HIF-1α/PTRF axis-mediated bioenergetic disturbance exacerbates cerebral ischemia-reperfusion injury via PLA2G4A.

Ischemic stroke is an acute and severe neurological disease with high mortality and disability rates worldwide. Polymerase I and transcript release factor (PTRF) plays a pivotal role in regulating cellular senescence, glucose intolerance, lipid metabolism, and mitochondrial bioenergetics, but its mechanism, characteristics, and functions in neuronal cells following the cerebral ischemia-reperfusion (I/R) injury remain to be determined. Methods: Transcription factor motif analysis, chromatin immunoprecipitation (ChIP), luciferase and co-Immunoprecipitation (co-IP) assays were performed to investigate the mechanisms of PTRF in neuronal cells after I/R injury. Lentiviral-sgRNA against PTRF gene was introduced to HT22 cells, and adeno-associated virus (AAV) encoding a human synapsin (hSyn) promoter-driven construct was transduced a short hairpin RNA (shRNA) against PTRF mRNA in primary neuronal cells and the cortex of the cerebral I/R mice for investigating the role of PTRF in neuronal damage and PLA2G4A change induced by the cerebral I/R injury. Results: Here, we reported that neuronal PTRF was remarkably increased in the cerebral penumbra after I/R injury, and HIF-1α and STAT3 regulated the I/R-dependent expression of PTRF via binding to its promoter in neuronal cells. Moreover, overexpression of neuronal PTRF enhanced the activity and stability of PLA2G4A by decreasing its proteasome-mediated degradation pathway. Subsequently, PTRF promoted reprogramming of lipid metabolism and altered mitochondrial bioenergetics, which could lead to oxidative damage, involving autophagy, lipid peroxidation, and ferroptosis via PLA2G4A in neuronal cells. Furthermore, inhibition of neuronal PTRF/PLA2G4A-axis markedly reduced the neurological deficits, cerebral infarct volumes, and mortality rates in the mice following cerebral I/R injury. Conclusion: Our results thus identify that the STAT3/HIF-1α/PTRF-axis in neurons, aggravating cerebral I/R injury by regulating the activity and stability of PLA2G4A, might be a novel therapeutic target for ischemic stroke.

lncRNA PRADX is a Mesenchymal Glioblastoma Biomarker for Cellular Metabolism Targeted Therapy.

Glioblastoma (GBM) is the most common and lethal type of primary malignant central nervous system (CNS) tumor with an extremely poor prognosis, and the mesenchymal subtype of GBM has the worst prognosis. Here, we found that lncRNA PRADX was overexpressed in the mesenchymal GBM and was transcriptionally regulated by RUNX1-CBFß complex, overexpressed PRADX suppressed BLCAP expression via interacting with EZH2 and catalyzing trimethylation of lysine 27 on histone H3 (H3K27me3). Moreover, we showed that BLCAP interacted with STAT3 and reduced STAT3 phosphorylation, overexpressed PRADX activated STAT3 phosphorylation, and promoted ACSL1 expression via suppressing BLCAP expression, accelerating tumor metabolism. Finally, we determined that combined of ACSL1 and CPT1 inhibitors could reverse the accelerated cellular metabolism and tumor growth induced by PRADX overexpression in vivo and in vitro. Collectively, PRADX/PRC2 complex activated the STAT3 pathway and energy metabolism in relation to mesenchymal GBM progression. Furthermore, our findings provided a novel therapeutic strategy targeting the energy metabolism activity of GBM.

Glioma-derived exosomes hijack the blood-brain barrier to facilitate nanocapsule delivery via LCN2.

Exosomes are small extracellular vehicles which could transport genetic materials and proteins between cells. Although there are reports about exosomes crossing the blood-brain barrier (BBB), the underlying mechanisms still need further study. We found that exosomes from primary brain tumors could upregulate the expression of Lipocalin-2 (LCN2) in bEnd.3 brain microvascular endothelial cells (BMVECs). Furthermore, exosomes increased the membrane fluidity of bEnd.3 cells in an LCN2 dependent manner. Both intraperitoneal injection and caudal vein injection of LCN2 increased the number of nanocapsules crossing the BBB. Evans Blue staining revealed that LCN2 does not interrupt the integrity of the BBB, as observed in the traumatic brain injury model. Tandem mass tags quantitative proteomics and bioinformatics analysis revealed that LCN2 is upregulated by exosomes via the JAK-STAT3 pathway, but not delivered from exosomes. Knocking down LCN2 in bEnd.3 cells significantly abrogated the effect of exosomes on BMVEC membrane fluidity. Previously, we have reported that 2-methacryloyloxyethyl phosphorylcholine (MPC) and a peptide crosslinker could encapsulate mAbs to achieve nanocapsules. The nanocapsules containing choline analogs could effectively penetrate the BBB to deliver therapeutic monoclonal antibodies (tAbs) to the glioma. However, the delivered tAbs could be significantly reduced by blocking the release of exosomes from the gliomas. Application of tAb nanocapsules prior to treatment with MK2206, an AKT pathway inhibitor that has been shown to inhibit the production of exosomes, resulted in a better combination. Insights from this study provide a mechanistic framework with regard to how glioblastomas hijack BMVECs using exosomes. In addition, we provide a strategy for maximizing the effect of the choline-containing nanocapsules and MK2206 combination. These results also demonstrate the therapeutic role of tAbs in glioblastoma and brain tumor metastasis, by shedding new light on strategies that can be used for BBB-penetrating therapies.

Blood exosomes-based targeted delivery of cPLA2 siRNA and metformin to modulate glioblastoma energy metabolism for tailoring personalized therapy.

BACKGROUND: Targeting glioblastoma (GBM) energy metabolism through multiple metabolic pathways has emerged as an effective therapeutic approach. Dual inhibition of phospholipid and mitochondrial metabolism with cytoplasmic phospholipase A2 (cPLA2) knockdown and metformin treatment could be a potential strategy. However, the strategic prerequisite is to explore a carrier capable of co-delivering the therapeutic combination to cross the blood-brain barrier (BBB) and preferentially accumulate at the GBM site. METHODS: Blood exosomes (Exos) were selected as the combination delivery carriers. The cellular uptake of Exos and the therapeutic effects of the combination strategy were evaluated in primary GBM cells. In vivo GBM-targeted delivery efficiency and anti-GBM efficacy were tested in a patient-derived xenograft (PDX) model. RESULTS: Here, we showed that the Exos-mediated cPLA2 siRNA/metformin combined strategy could regulate GBM energy metabolism for personalized treatment. Genomic analysis and experiments showed that polymerase 1 and transcript release factor (PTRF, a biomarker of GBM) positively regulated the uptake of Exos by GBM cells, confirming the feasibility of the delivery strategy. Further, Exos could co-load cPLA2 siRNA (sicPLA2) and metformin and co-deliver them across the BBB and into GBM tissue. The mitochondrial energy metabolism of GBM was impaired with this combination treatment (Exos-Met/sicPLA2). In the PDX GBM model, systemic administration of Exos-Met/sicPLA2 reduced tumor growth and prolonged survival. CONCLUSIONS: Our findings demonstrated that Exos-based combined delivery of sicPLA2 and metformin selectively targeted the GBM energy metabolism to achieve antitumor effects, showing its potential as a personalized therapy for GBM patients.