Blood-Brain Barrier Penetrating Nanovehicles for Interfering with Mitochondrial Electron Flow in Glioblastoma.

Glioblastoma multiforme (GBM) is the most aggressive and lethal form of human brain tumors. Dismantling the suppressed immune microenvironment is an effective therapeutic strategy against GBM; however, GBM does not respond to exogenous immunotherapeutic agents due to low immunogenicity. Manipulating the mitochondrial electron transport chain (ETC) elevates the immunogenicity of GBM, rendering previously immune-evasive tumors highly susceptible to immune surveillance, thereby enhancing tumor immune responsiveness and subsequently activating both innate and adaptive immunity. Here, we report a nanomedicine-based immunotherapeutic approach that targets the mitochondria in GBM cells by utilizing a Trojan-inspired nanovector (ABBPN) that can cross the blood-brain barrier. We propose that the synthetic photosensitizer IrPS can alter mitochondrial electron flow and concurrently interfere with mitochondrial antioxidative mechanisms by delivering si-OGG1 to GBM cells. Our synthesized ABBPN coloaded with IrPS and si-OGG1 (ISA) disrupts mitochondrial electron flow, which inhibits ATP production and induces mitochondrial DNA oxidation, thereby recruiting immune cells and endogenously activating intracranial antitumor immune responses. The results of our study indicate that strategies targeting the mitochondrial ETC have the potential to treat tumors with limited immunogenicity.

mRNA-Laden Lipid-Nanoparticle-Enabled in Situ CAR-Macrophage Engineering for the Eradication of Multidrug-Resistant Bacteria in a Sepsis Mouse Model.

Sepsis, which is the most severe clinical manifestation of acute infection and has a mortality rate higher than that of cancer, represents a significant global public health burden. Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection and further host immune paralysis are the leading causes of sepsis-associated death, but limited clinical interventions that target sepsis have failed to effectively restore immune homeostasis to enable complete eradication of MRSA. To restimulate anti-MRSA innate immunity, we developed CRV peptide-modified lipid nanoparticles (CRV/LNP-RNAs) for transient in situ programming of macrophages (MΦs). The CRV/LNP-RNAs enabled the delivery of MRSA-targeted chimeric antigen receptor (CAR) mRNA (SasA-CAR mRNA) and CASP11 (a key MRSA intracellular evasion target) siRNA to MΦs in situ, yielding CAR-MΦs with boosted bactericidal potency. Specifically, our results demonstrated that the engineered MΦs could efficiently phagocytose and digest MRSA intracellularly, preventing immune evasion by the "superbug" MRSA. Our findings highlight the potential of nanoparticle-enabled in vivo generation of CAR-MΦs as a therapeutic platform for multidrug-resistant (MDR) bacterial infections and should be confirmed in clinical trials.

Copy number gain of FAM131B-AS2 promotes the progression of glioblastoma by mitigating replication stress.

BACKGROUND: Glioblastoma (GBM) is characterized by chromosome 7 copy number gains, notably 7q34, potentially contributing to therapeutic resistance, yet the underlying oncogenes have not been fully characterized. Pertinently, the significance of long noncoding RNAs (lncRNAs) in this context has gained attention, necessitating further exploration. METHODS: FAM131B-AS2 was quantified in GBM samples and cells using qPCR. Overexpression and knockdown of FAM131B-AS2 in GBM cells were used to study its functions in vivo and in vitro. The mechanisms of FAM131B-AS2 were studied using RNA-seq, qPCR, Western blotting, RNA pull-down, coimmunoprecipitation assays, and mass spectrometry analysis. The phenotypic changes that resulted from FAM131B-AS2 variation were evaluated through CCK8 assay, EdU assay, comet assay, and immunofluorescence. RESULTS: Our analysis of 149 primary GBM patients identified FAM131B-AS2, a lncRNA located in the 7q34 region, whose upregulation predicts poor survival. Mechanistically, FAM131B-AS2 is a crucial regulator of the replication stress response, stabilizing RPA1 through recruitment of USP7 and activating the ATR pathway to protect single-stranded DNA from breakage. Furthermore, FAM131B-AS2 overexpression inhibited CD8+ T-cell infiltration, while FAM131B-AS2 inhibition activated the cGAS-STING pathway, increasing lymphocyte infiltration and improving the response to immune checkpoint inhibitors. CONCLUSION: FAM131B-AS2 emerges as a promising indicator for adjuvant therapy response and could also be a viable candidate for combined immunotherapies against GBMs.

Intracavitary Spraying of Nanoregulator-Encased Hydrogel Modulates Cholesterol Metabolism of Glioma-Supportive Macrophage for Postoperative Glioblastoma Immunotherapy.

Glioblastoma multiforme (GBM) is notoriously resistant to immunotherapy due to its intricate immunosuppressive tumor microenvironment (TME). Dysregulated cholesterol metabolism is implicated in the TME and promotes tumor progression. Here, it is found that cholesterol levels in GBM tissues are abnormally high, and glioma-supportive macrophages (GSMs), an essential "cholesterol factory", demonstrate aberrantly hyperactive cholesterol metabolism and efflux, providing cholesterol to fuel GBM growth and induce CD8+ T cells exhaustion. Bioinformatics analysis confirms that high 7-dehydrocholesterol reductase (DHCR7) level in GBM tissues associates with increased cholesterol biosynthesis, suppressed tumoricidal immune response, and poor patient survival, and DHCR7 expression level is significantly elevated in GSMs. Therefore, an intracavitary sprayable nanoregulator (NR)-encased hydrogel system to modulate cholesterol metabolism of GSMs is reported. The degradable NR-mediated ablation of DHCR7 in GSMs effectively suppresses cholesterol supply and activates T-cell immunity. Moreover, the combination of Toll-like receptor 7/8 (TLR7/8) agonists significantly promotes GSM polarization to antitumor phenotypes and ameliorates the TME. Treatment with the hybrid system exhibits superior antitumor effects in the orthotopic GBM model and postsurgical recurrence model. Altogether, the findings unravel the role of GSMs DHCR7/cholesterol signaling in the regulation of TME, presenting a potential treatment strategy that warrants further clinical trials.

Metabolic Modulation of Histone Acetylation Mediated by HMGCL Activates the FOXM1/ß-catenin Pathway in Glioblastoma.

BACKGROUND: Altered branched-chain amino acid (BCAA) metabolism modulates epigenetic modification, such as H3K27ac in cancer, thus providing a link between metabolic reprogramming and epigenetic change, which are prominent hallmarks of glioblastoma multiforme (GBM). Here, we identified mitochondrial 3-hydroxymethyl-3-methylglutaryl-CoA lyase (HMGCL), an enzyme involved in leucine degradation, promoting GBM progression and glioma stem cell (GSC) maintenance. METHODS: In silico analysis was performed to identify specific molecules involved in multiple processes. GBM cells were infected with knockdown/overexpression lentiviral constructs of HMGCL to assess malignant performance in vitro and in an orthotopic xenograft model. RNA sequencing was used to identify potential downstream molecular targets. RESULTS: HMGCL as a gene increased in GBM and associated with poor survival in patients. Knockdown of HMGCL suppressed proliferation and invasion in vitro and in vivo. Acetyl-CoA was decreased with HMGCL knockdown, which led to reduced NFAT1 nuclear accumulation and H3K27ac level. RNA sequencing-based transcriptomic profiling revealed FOXM1 as a candidate downstream target, and HMGCL-mediated H3K27ac modification in the FOXM1 promoter induced transcription of the gene. Loss of FOXM1 protein with HMGCL knockdown led to decreased nuclear translocation and thus activity of ß-catenin, a known oncogene. Finally, JIB-04, a small molecule confirmed to bind to HMGCL, suppressed GBM tumorigenesis in vitro and in vivo. CONCLUSIONS: Changes in acetyl-CoA levels induced by HMGCL altered H3K27ac modification, which triggers transcription of FOXM1 and ß-catenin nuclear translocation. Targeting HMGCL by JIB-04 inhibited tumor growth, indicating that mediators of BCAA metabolism may serve as molecular targets for effective GBM treatment.

Restoring neuronal iron homeostasis revitalizes neurogenesis after spinal cord injury.

Spinal cord injury (SCI) can lead to iron overloading and subsequent neuronal ferroptosis, which hinders the recovery of locomotor function. However, it is still unclear whether the maintenance of neuronal iron homeostasis enables to revitalize intrinsic neurogenesis. Herein, we report the regulation of cellular iron homeostasis after SCI via the chelation of excess iron ions and modulation of the iron transportation pathway using polyphenol-based hydrogels for the revitalization of intrinsic neurogenesis. The reversed iron overloading can promote neural stem/progenitor cell differentiation into neurons and elicit the regenerative potential of newborn neurons, which is accompanied by improved axon reinnervation and remyelination. Notably, polyphenol-based hydrogels significantly increase the neurological motor scores from ~8 to 18 (out of 21) and restore the transmission of sensory and motor electrophysiological signals after SCI. Maintenance of iron homeostasis at the site of SCI using polyphenol-based hydrogels provides a promising paradigm to revitalize neurogenesis for the treatment of iron accumulation-related nervous system diseases.

Applicative Assessment of a Selective Laser Melting 3D-Printed Ti-6Al-4 V Plate with a Honeycomb Structure in the Reconstruction of a Mandibular Defect of a Beagle Dog.

The most challenging problem in oral and maxillofacial surgery is the reconstruction of defects for the oral and maxillofacial complex. Transfer of different autografts is known as the "gold standard" for the reconstruction of bone defects in the oral and maxillofacial region. Graft harvesting, however, can lead to many complications, such as donor-site morbidity, surgical time-consuming, etc. Three-dimensional (3D) printing technology is an innovative technique that allows the fabrication of personalized plates and scaffolds to fit the precise anatomy of an individual's defect. In this study, a selective laser melting 3D-printed Ti-6Al-4 V plate with a honeycomb was designed, and its physical and biological features were characterized. The personalized 3D-printed scaffold and commercialized titanium reconstruction plate were applied to reconstruct a 4 cm mandibular defect in a beagle dog. Effects of the treatment were analyzed radiologically and histologically. Our results showed that the application of a 3D-printed plate with a honeycomb achieved good biocompatibility and osseointegration and has potential clinical application.

Three-dimensional nanofibrous sponges with aligned architecture and controlled hierarchy regulate neural stem cell fate for spinal cord regeneration.

Background: Spinal cord injury (SCI) induces neuronal death and disrupts the nerve fiber bundles, which leads to severe neurological dysfunction and even permanent paralysis. A strategy combining biomimetic nanomaterial scaffolds with neural stem cell (NSC) transplantation holds promise for SCI treatment. Methods: Innovative three-dimensional (3D) nanofibrous sponges (NSs) were designed and developed by a combination of directional electrospinning and subsequent gas-foaming treatment. Immunofluorescence, mRNA sequencing, magnetic resonance imaging, electrophysiological analysis, and behavioral tests were used to investigate the in vitro and in vivo regenerative effects of the 3D NSs. Results: The generated 3D NSs exhibited uniaxially aligned nano-architecture and highly controllable hierarchical structure with super-high porosity (99%), outstanding hydrophilicity, and reasonable mechanical performance. They facilitated cell infiltration, induced cell alignment, promoted neuronal differentiation of NSCs, and enhanced their maturation mediated through cellular adhesion molecule pathways. In vivo, the NSC-seeded 3D NSs efficiently promoted axon reinnervation and remyelination in a rat SCI model, with new "neural relays" developing across the lesion gap. These histological changes were associated with regain of function, including increasing the neurological motor scores of SCI rats, from approximately 2 to 16 (out of 21), and decreasing the sensing time in the tape test from 140 s to 36 s. Additionally, the scaffolds led to restoration of ascending and descending electrophysiological signalling. Conclusion: The as-fabricated 3D NSs effectively regulate NSC fates, and an advanced combination of 3D NS design and transplanted NSCs enables their use as an ideal tissue-engineered scaffold for SCI repair.

National Brain Tumour Registry of China (NBTRC) statistical report of primary brain tumours diagnosed in China in years 2019-2020.

Background: The lack of a well-designed brain tumour registry with standardized pathological diagnoses in underdeveloped countries hinders the ability to compare epidemiologic data across the globe. The National Brain Tumour Registry of China (NBTRC), created in January 2018, is the first multi-hospital-based brain tumour registry in China. Patient data reported to the NBTRC in years 2019-2020 were assessed. Methods: Tumour pathology was based on the 2016 World Health Organization (WHO) classification of tumours of the central nervous system and ICD-O-3. The anatomical site was coded per the Surveillance, Epidemiology, and End Results (SEER) solid tumour module (version of July 2019). The cases were tabulated by histology and anatomical site. Categorical variables were reported as numbers (percentages). The distribution of tumours by age (0-14, 15-19, 20-39, 40-64, and 65+ years) was analysed. Findings: There were a total of 25,537 brain tumours, foremost among them meningioma (23.63%), followed by tumours of the pituitary (23.42%), and nerve sheath tumours (9.09%). Glioblastoma, the most common and lethal form of primary brain cancer in adults, represented 8.56% of all cases. Of note, 6.48% of the malignant tumours were located in the brain stem. The percentage of malignant brain tumours decreased with increasing age, 24.08% in adults (40+ years), 30.25% in young adults (20-39 years), 35.27% in adolescents (15-19 years), and 49.83% in children (0-14 years). Among the 2107 paediatric patients, the most common sites were ventricle (17.19%), brainstem (14.03%), pituitary and craniopharyngeal duct (13.4%), and cerebellum (12.3%), a distribution that differed from that of the entire cohort. The histology distribution was also unique in children, with glioblastoma much less incident compared to the whole cohort (3% vs. 8.47%, p < 0.01). 58.80% of all patients chose higher-level neurosurgical hospitals outside of their province of residence. The median in-hospital length of stay (LOS) for the various pathologies ranged from 11 to 19 days. Interpretation: The histological and anatomical site distribution of brain tumours in the NBTRC was statistically different in the subgroup of children (0-14 years). Patient choice of pursuing trans-provincial treatment was common and the in-hospital LOS was longer compared to that reported in similar European and American patient populations, which merits further attention. Funding: The National Key Research and Development Program of China (2015BAI12B04, 2013BAI09B03, 2014BAI04B01, and 2021YFF1201104) and Chinese National Natural Science Foundation of China (81971668).

The first prospective application of AIGS real-time fluorescence PCR in precise diagnosis and treatment of meningioma: Case report.

Background: The emergence of the new WHO classification standard in 2021 incorporated molecular characteristics into the diagnosis system for meningiomas, making the diagnosis and treatment of meningiomas enter the molecular era. Recent findings: At present, there are still some problems in the clinical molecular detection of meningioma, such as low attention, excessive detection, and a long cycle. In order to solve these clinical problems, we realized the intraoperative molecular diagnosis of meningioma by combining real-time fluorescence PCR and AIGS, which is also the first known product applied to the intraoperative molecular diagnosis of meningioma. Implications for practice: We applied AIGS to detect and track a patient with TERTp mutant meningioma, summarized the process of intraoperative molecular diagnosis, and expounded the significance of intraoperative molecular diagnosis under the new classification standard, hoping to optimize the clinical decision-making of meningioma through the diagnosis and treatment plan of this case.

Nervous tract-bioinspired multi-nanoyarn model system regulating neural differentiation and its transcriptional architecture at single-cell resolution.

Bioinspired by native nervous tracts, a spinal cord-mimicking model system that was composed of multiple nanofibrous yarns (NYs) ensheathed in a nanofibrous tube was constructed by an innovative electrospinning-based fabrication and integration strategy. The infilling NYs exhibited uniaxially aligned nanofibrous architecture that had a great resemblance to spatially-arranged native nervous tracts, while the outer nanofibrous tubes functioned as an artificial dura matter to provide a stable intraluminal microenvironment. The three-dimensional (3D) NYs were demonstrated to induce alignment, facilitate migration, promote neuronal differentiation, and even phenotypic maturation of seeded neural stem and progenitor cells (NSPCs), while inhibiting gliogenesis. Single-cell transcriptome analysis showed that the NSPC-loaded 3D NY model shared many similarities with native spinal cords, with a great increase in excitatory/inhibitory (EI) neuron ratio. Curcumin, as a model drug, was encapsulated into nanofibers of NYs to exert an antioxidant effect and enhanced axon regeneration. Overall, this study provides a new paradigm for the development of a next-generation in vitro neuronal model system via anatomically accurate nervous tract simulation and constructs a blueprint for the research on NSPC diversification in the biomimetic microenvironment.

Solitary Sclerotic Fibroma of Right Cerebellopontine Angle.

Sclerotic fibroma (storiform collagenoma) is a fibrotic tumor that occurs mainly in patients with Cowden syndrome, but it can also occur in isolation, as detailed in previous reports. Here we present a case of a solitary sclerotic fibroma in cerebellopontine angle. Brain magnetic resonance imaging revealed a lesion showing hypointense signal on both T1 and T2. The lesion was not enhanced after administering gadolinium. The tumor was removed integrally by surgery.

Application of Intraoperative Rapid Molecular Diagnosis in Precision Surgery for Glioma: Mimic the World Health Organization CNS5 Integrated Diagnosis.

BACKGROUND: With the advent of the molecular era, the diagnosis and treatment systems of glioma have also changed. A single histological type cannot be used for prognosis grade. Only by combining molecular diagnosis can precision medicine be realized. OBJECTIVE: To develop an automatic integrated gene detection system (AIGS) for intraoperative detection in glioma and to explore its positive role in intraoperative diagnosis and treatment. METHODS: We analyzed the isocitrate dehydrogenase 1 (IDH1) mutation status of 105 glioma samples and evaluated the product's potential value for diagnosis; 37 glioma samples were detected intraoperatively to evaluate the feasibility of using the product in an actual situation. A blinding method was used to evaluate the effect of the detection technology on the accuracy of intraoperative histopathological diagnosis by pathologists. We also reviewed the current research status in the field of intraoperative molecular diagnosis. RESULTS: Compared with next-generation sequencing, the accuracy of AIGS in detecting IDH1 was 100% for 105 samples and 37 intraoperative samples. The blind diagnostic results were compared between the 2 groups, and the molecular information provided by AIGS increased the intraoperative diagnostic accuracy of glioma by 16.2%. Using the technical advantages of multipoint synchronous detection, we determined the tumor molecular margins for 5 IDH-positive patients and achieved accurate resection at the molecular level. CONCLUSION: AIGS can quickly and accurately provide molecular information during surgery. This methodology not only improves the accuracy of intraoperative pathological diagnosis but also provides an important molecular basis for determining tumor margins to facilitate precision surgery.

Targeting tumor-associated macrophages for the immunotherapy of glioblastoma: Navigating the clinical and translational landscape.

Tumor-associated macrophages (TAMs) can directly clear tumor cells and enhance the phagocytic ability of immune cells. An abundance of TAMs at the site of the glioblastoma tumor indicates that TAM-targeting immunotherapy could represent a potential form of treatment for this aggressive cancer. Herein, we discuss: i) the dynamic role of TAMs in glioblastoma; ii) describe the formation of the immunosuppressive tumor microenvironment; iii) summarize the latest clinical trial data that reveal how TAM function can be regulated in favor tumor eradication; and lastly, iv) evaluate the implications of existing and novel translational approaches for treating glioblastoma in clinical practice.

Metformin carbon nanodots promote odontoblastic differentiation of dental pulp stem cells by pathway of autophagy.

Human dental pulp stem cells (hDPSCs) have been a focus of pulp regeneration research because of their excellent odontogenic potential and availability. Applying the odontoblastic differentiation of hDPSCs to tooth regeneration has been challenging. Metformin-based carbon nanodots (MCDs) were synthesized and characterized to investigate their effects in vitro on odontoblastic hDPSC differentiation and the underlying mechanism. MCDs were synthesized by a hydrothermal treatment method and characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The biocompatibility and fluorescence properties of the MCDs in Dulbecco's modified Eagle's medium high-glucose culture medium and the in vitro odontogenic potential and related mechanism of the bioactive nanomaterial was explored. TEM images showed that MCDs were spherical in shape with a size of approximately 5.9 nm. MCDs showed biological safety in cell viability, apoptosis, and fluorescence labelling ability at a concentration up to 200 µg/ml in vitro. The presence of MCDs facilitated high-efficiency odontogenic differentiation of hDPSCs by promoting odontogenic gene and protein expression. Moreover, MCDs promoted odontoblastic hDPSC differentiation via autophagy. MCDs are capable of activating autophagy and enhancing the odontogenic differentiation of hDPSCs by upregulating odontoblast gene marker (DMP1, DSPP, RUNX2, and SP7) and protein (DSPP and DMP1) expression.

Donors for nerve transplantation in craniofacial soft tissue injuries.

Neural tissue is an important soft tissue; for instance, craniofacial nerves govern several aspects of human behavior, including the expression of speech, emotion transmission, sensation, and motor function. Therefore, nerve repair to promote functional recovery after craniofacial soft tissue injuries is indispensable. However, the repair and regeneration of craniofacial nerves are challenging due to their intricate anatomical and physiological characteristics. Currently, nerve transplantation is an irreplaceable treatment for segmental nerve defects. With the development of emerging technologies, transplantation donors have become more diverse. The present article reviews the traditional and emerging alternative materials aimed at advancing cutting-edge research on craniofacial nerve repair and facilitating the transition from the laboratory to the clinic. It also provides a reference for donor selection for nerve repair after clinical craniofacial soft tissue injuries. We found that autografts are still widely accepted as the first options for segmental nerve defects. However, allogeneic composite functional units have a strong advantage for nerve transplantation for nerve defects accompanied by several tissue damages or loss. As an alternative to autografts, decellularized tissue has attracted increasing attention because of its low immunogenicity. Nerve conduits have been developed from traditional autologous tissue to composite conduits based on various synthetic materials, with developments in tissue engineering technology. Nerve conduits have great potential to replace traditional donors because their structures are more consistent with the physiological microenvironment and show self-regulation performance with improvements in 3D technology. New materials, such as hydrogels and nanomaterials, have attracted increasing attention in the biomedical field. Their biocompatibility and stimuli-responsiveness have been gradually explored by researchers in the regeneration and regulation of neural networks.

Porous construction and surface modification of titanium-based materials for osteogenesis: A review.

Titanium and titanium alloy implants are essential for bone tissue regeneration engineering. The current trend is toward the manufacture of implants from materials that mimic the structure, composition and elasticity of bones. Titanium and titanium alloy implants, the most common materials for implants, can be used as a bone conduction material but cannot promote osteogenesis. In clinical practice, there is a high demand for implant surfaces that stimulate bone formation and accelerate bone binding, thus shortening the implantation-to-loading time and enhancing implantation success. To avoid stress shielding, the elastic modulus of porous titanium and titanium alloy implants must match that of bone. Micro-arc oxidation technology has been utilized to increase the surface activity and build a somewhat hard coating on porous titanium and titanium alloy implants. More recently, a growing number of researchers have combined micro-arc oxidation with hydrothermal, ultrasonic, and laser treatments, coatings that inhibit bacterial growth, and acid etching with sand blasting methods to improve bonding to bone. This paper summarizes the reaction at the interface between bone and implant material, the porous design principle of scaffold material, MAO technology and the combination of MAO with other technologies in the field of porous titanium and titanium alloys to encourage their application in the development of medical implants.

Synchronous Disintegration of Ferroptosis Defense Axis via Engineered Exosome-Conjugated Magnetic Nanoparticles for Glioblastoma Therapy.

Glioblastoma (GBM) is one of the most fatal central nervous system tumors and lacks effective or sufficient therapies. Ferroptosis is a newly discovered method of programmed cell death and opens a new direction for GBM treatment. However, poor blood-brain barrier (BBB) penetration, reduced tumor targeting ability, and potential compensatory mechanisms hinder the effectiveness of ferroptosis agents during GBM treatment. Here, a novel composite therapeutic platform combining the magnetic targeting features and drug delivery properties of magnetic nanoparticles with the BBB penetration abilities and siRNA encapsulation properties of engineered exosomes for GBM therapy is presented. This platform can be enriched in the brain under local magnetic localization and angiopep-2 peptide-modified engineered exosomes can trigger transcytosis, allowing the particles to cross the BBB and target GBM cells by recognizing the LRP-1 receptor. Synergistic ferroptosis therapy of GBM is achieved by the combined triple actions of the disintegration of dihydroorotate dehydrogenase and the glutathione peroxidase 4 ferroptosis defense axis with Fe3 O4 nanoparticle-mediated Fe2+ release. Thus, the present findings show that this system can serve as a promising platform for the treatment of glioblastoma.