Tumor cellular membrane camouflaged liposomes as a non-invasive vehicle for genes: specific targeting toward homologous gliomas and traversing the blood-brain barrier

Advanced nanoparticle engineering for precision therapeutics of brain diseases

Despite the increasing global prevalence of neurological disorders, the development of nanoparticle (NP) technologies for brain-targeted therapies confronts considerable challenges. One of the key obstacles in treating brain diseases is the blood-brain barrier (BBB), which restricts the penetration of NP-based therapies into the brain. To address this issue, NPs can be installed with specific ligands or bioengineered to boost their precision and efficacy in targeting brain-diseased cells by navigating across the BBB, ultimately improving patient treatment outcomes. At the outset of this review, we highlighted the critical role of ligand-functionalized or bioengineered NPs in treating brain diseases from a clinical perspective. We then identified the key obstacles and challenges NPs encounter during brain delivery, including immune clearance, capture by the reticuloendothelial system (RES), the BBB, and the complex post-BBB microenvironment. Following this, we overviewed the recent progress in NPs engineering, focusing on ligand-functionalization or bionic designs to enable active BBB transcytosis and targeted delivery to brain-diseased cells. Lastly, we summarized the critical challenges hindering clinical translation, including scalability issues and off-target effects, while outlining future opportunities for designing cutting-edge brain delivery technologies.

Polymer-based nanocarriers to transport therapeutic biomacromolecules across the blood-brain barrier

Therapeutic biomacromolecules such as genetic material, antibodies, growth factors and enzymes represent a novel therapeutic alternative for neurological diseases and disorders. In comparison to traditional therapeutics, which are mainly based on small molecular weight drugs that address the symptoms of these disorders, therapeutic biomacromolecules can reduce undesired side effects and target specific pathological pathways, thus paving the way towards personalized medicine. However, these biomacromolecules undergo degradation/denaturation processes in the physiological environment and show poor capacity to cross the blood-brain barrier (BBB). Consequently, they rarely reach the central nervous system (CNS) in their active form. Herein, we critically overview several polymeric nanocarriers that can protect and deliver therapeutic biomacromolecules across the BBB. Polymeric nanocarriers are first categorized based on their architecture (biodegradable solid nanoparticles, nanogels, dendrimers, self-assembled nanoparticles) that ultimately determines their physico-chemical properties and function. The available polymeric formulations are then thoroughly analyzed, placing particular attention on those strategies that ensure the stability of the biomacromolecules during their encapsulation process and promote their passage across the BBB by controlling their physical (e.g., mechanical properties, size, surface charge) and chemical (e.g., surface functional groups, targeting motifs) properties. Accordingly, this review gives a unique perspective on polymeric nanocarriers for the delivery of therapeutic biomacromolecules across the BBB, representing a concise, complete and easy-to-follow guide, which will be of high interest for chemists, material scientists, pharmacologists, and biologists. Besides, it also provides a critical perspective about the limited clinical translation of these systems. STATEMENT OF SIGNIFICANCE: The increasing incidence of central nervous system disorders is a major health concern. The use of therapeutic biomacromolecules has been placed in the spotlight of many investigations. However, reaching therapeutic concentration levels of biomacromolecules in the central nervous system is restricted by the blood-brain barrier and, thus, this represents the main clinical challenge when developing efficient therapies. Herein, we provide a critical discussion about the use of polymeric nanocarriers to deliver therapeutic biomacromolecules into the central nervous system, highlighting potential future directions to overcome the current challenges.

Advancing neurological disorders therapies: Organic nanoparticles as a key to blood-brain barrier penetration

The blood-brain barrier (BBB) plays a vital role in protecting the central nervous system (CNS) by preventing the entry of harmful pathogens from the bloodstream. However, this barrier also presents a significant obstacle when it comes to delivering drugs for the treatment of neurodegenerative diseases and brain cancer. Recent breakthroughs in nanotechnology have paved the way for the creation of a wide range of nanoparticles (NPs) that can serve as carriers for diagnosis and therapy. Regarding their promising properties, organic NPs have the potential to be used as effective carriers for drug delivery across the BBB based on recent advancements. These remarkable NPs have the ability to penetrate the BBB using various mechanisms. This review offers a comprehensive examination of the intricate structure and distinct properties of the BBB, emphasizing its crucial function in preserving brain balance and regulating the transport of ions and molecules. The disruption of the BBB in conditions such as stroke, Alzheimer's disease, and Parkinson's disease highlights the importance of developing creative approaches for delivering drugs. Through the encapsulation of therapeutic molecules and the precise targeting of transport processes in the brain vasculature, organic NP formulations present a hopeful strategy to improve drug transport across the BBB. We explore the changes in properties of the BBB in various pathological conditions and investigate the factors that affect the successful delivery of organic NPs into the brain. In addition, we explore the most promising delivery systems associated with NPs that have shown positive results in treating neurodegenerative and ischemic disorders. This review opens up new possibilities for nanotechnology-based therapies in cerebral diseases.

Combined Strategies for Nanodrugs Noninvasively Overcoming the Blood-Brain Barrier and Actively Targeting Glioma Lesions

Drugs for tumor treatment face various challenges, including poor solubility, poor stability, short blood half-life, nontargeting ability, and strong toxic side effects. Fortunately, nanodrug delivery systems provide excellent solution to these problems. However, nanodrugs for glioma treatment also face some key challenges including overcoming the blood-brain barrier (BBB) and, specifically, accumulation in glioma lesions. In this review, we systematically summarize the advantages and disadvantages of combined strategies for nanodrugs noninvasively overcoming BBB and actively targeting glioma lesions to achieve effective glioma therapy. Common noninvasive strategies for nanodrugs overcoming the BBB include bypassing the BBB via the nose-to-brain route, opening the tight junction of the BBB by focused ultrasound with microbubbles, and transendothelial cell transport by intact cell loading, ligand decoration, or cell membrane camouflage of nanodrugs. Actively targeting glioma lesions after overcoming the BBB is another key factor helping nanodrugs accurately treat in situ gliomas. This aim can also be achieved by loading nanodrugs into intact cells and modifying ligand or cell membrane fragments on the surface of nanodrugs. Targeting decorated nanodrugs can guarantee precise glioma killing and avoid side effects on normal brain tissues that contribute to the specific recognition of glioma lesions. Furthermore, the challenges and prospects of nanodrugs in clinical glioma treatment are discussed.

Biohybrid nano-platforms manifesting effective cancer therapy: Fabrication, characterization, challenges and clinical perspective

Nanotechnology-based delivery systems have brought a paradigm shift in the management of cancer. However, the main obstacles to nanocarrier-based delivery are their limited circulation duration, excessive immune clearance, inefficiency in interacting effectively in a biological context and overcoming biological barriers. This demands effective engineering of nanocarriers to achieve maximum efficacy. Nanocarriers can be maneuvered with biological components to acquire biological identity for further regulating their biodistribution and cell-to-cell cross-talk. Thus, the integration of synthetic and biological components to deliver therapeutic cargo is called a biohybrid delivery system. These delivery systems possess the advantage of synthetic nanocarriers, such as high drug loading, engineerable surface, reproducibility, adequate communication and immune evasion ability of biological constituents. The biohybrid delivery vectors offer an excellent opportunity to harness the synergistic properties of the best entities of the two worlds for improved therapeutic outputs. The major spotlights of this review are different biological components, synthetic counterparts of biohybrid nanocarriers, recent advances in hybridization techniques, and the design of biohybrid delivery systems for cancer therapy. Moreover, this review provides an overview of biohybrid systems with therapeutic and diagnostic applications. In a nutshell, this article summarizes the advantages and limitations of various biohybrid nano-platforms, their clinical potential and future directions for successful translation in cancer management.

Review of recent preclinical and clinical research on ligand-targeted liposomes as delivery systems in triple negative breast cancer therapy

Triple-negative breast Cancer (TNBC) is one of the deadliest types, making up about 20% of all breast cancers. Chemotherapy is the traditional manner of progressed TNBC treatment; however, it has a short-term result with a high reversibility pace. The lack of targeted treatment limited and person-dependent treatment options for those suffering from TNBC cautions to be the worst type of cancer among breast cancer patients. Consequently, appropriate treatment for this disease is considered a major clinical challenge. Therefore, various treatment methods have been developed to treat TNBC, among which chemotherapy is the most common and well-known approach recently studied. Although effective methods are chemotherapies, they are often accompanied by critical limitations, especially the lack of specific functionality. These methods lead to systematic toxicity and, ultimately, the expansion of multidrug-resistant (MDR) cancer cells. Therefore, finding novel and efficient techniques to enhance the targeting of TNBC treatment is an essential requirement. Liposomes have demonstrated that they are an effective method for drug delivery; however, among a large number of liposome-based drug delivery systems annually developed, a small number have just received authorization for clinical application. The new approaches to using liposomes target their structure with various ligands to increase therapeutic efficiency and diminish undesired side effects on various body tissues. The current study describes the most recent strategies and research associated with functionalizing the liposomes' structure with different ligands as targeted drug carriers in treating TNBCs in preclinical and clinical stages.

Brain targeted biomimetic siRNA nanoparticles for drug resistance glioblastoma treatment

Glioblastoma multiforme (GBM), the most aggressive intracranial neoplasm, remains incurable at present, primarily due to drug resistance, which significantly contributes to elevated recurrence rates and dismal prognosis. Signal transducer and activator of transcription 3 (STAT3) is a critical gene closely associated with GBM drug resistance and the progression of GBM stem cells (GSCs), making it a promising therapeutic target. In this study, we developed cancer cell membrane-cloaked biomimetic nanoparticles to deliver STAT3 siRNA to reverse drug resistance in homologous GBM. These biomimetic nanoparticles leverage homotypic targeting, rapid endosome escape, and fast siRNA release, leading to efficient in vitro STAT3 knockdown in both temozolomide-resistant U251-TR cells and X01 GSCs. Moreover, benefited from the membrane functionalization, significant prolonged blood circulation, improved blood brain barrier (BBB) penetration and GBM tumor accumulation are achieved by these siRNA biomimetic nanoparticles. Importantly, these nanoparticles effectively inhibit tumor proliferation, significantly extending median survival time in orthotopic U251-TR (43.5 d versus 20 d for PBS control) and X01 GSC-bearing mouse xenografts (52 d versus 19.5 d for PBS control). Altogether, this biomimetic siRNA platform offers a promising strategy for gene therapy targeting drug-resistant GBM.

Functionalized liposomes: an enticing nanocarrier for management of glioma

Glioma is one of the most severe central nervous systems (CNS)-specific tumors, with rapidly growing malignant glial cells accounting for roughly half of all brain tumors and having a poor survival rate ranging from 12 to 15 months. Despite being the most often used technique for glioma therapy, conventional chemotherapy suffers from low permeability of the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB) to anticancer drugs. When it comes to nanocarriers, liposomes are thought of as one of the most promising nanocarrier systems for glioma treatment. However, owing to BBB tight junctions, non-targeted liposomes, which passively accumulate in most cancer cells primarily via the increased permeability and retention effect (EPR), would not be suitable for glioma treatment. The surface modification of liposomes with various active targeting ligands has shown encouraging outcomes in the recent times by allowing various chemotherapy drugs to pass across the BBB and BBTB and enter glioma cells. This review article introduces by briefly outlining the landscape of glioma, its classification, and some of the pathogenic causes. Further, it discusses major barriers for delivering drugs to glioma such as the BBB, BBTB, and tumor microenvironment. It further discusses modified liposomes such as long-acting circulating liposomes, actively targeted liposomes, stimuli responsive liposomes. Finally, it highlighted the limitations of liposomes in the treatment of glioma and the various actively targeted liposomes undergoing clinical trials for the treatment of glioma.

A state-of-the-art liposome technology for glioblastoma treatment

Glioblastoma (GBM) is a challenging problem due to the poor BBB permeability of cancer drugs, its recurrence after the treatment, and high malignancy and is difficult to treat with the currently available therapeutic strategies. Furthermore, the prognosis and survival rate of GBM are still poor after surgical removal via conventional combination therapy. Owing to the existence of the formidable blood-brain barrier (BBB) and the aggressive, infiltrating nature of GBM growth, the diagnosis and treatment of GBM are quite challenging. Recently, liposomes and their derivatives have emerged as super cargos for the delivery of both hydrophobic and hydrophilic drugs for the treatment of glioblastoma because of their advantages, such as biocompatibility, long circulation, and ease of physical and chemical modification, which facilitate the capability of targeting specific sites, circumvention of BBB transport restrictions, and amplification of the therapeutic efficacy. Herein, we provide a timely update on the burgeoning liposome-based drug delivery systems and potential challenges in these fields for the diagnosis and treatment of brain tumors. Furthermore, we focus on the most recent liposome-based drug delivery cargos, including pH-sensitive, temperature-sensitive, and biomimetic liposomes, to enhance the multimodality in imaging and therapeutics of glioblastoma. Furthermore, we highlight the future difficulties and directions for the research and clinical translation of liposome-based drug delivery. Hopefully, this review will trigger the interest of researchers to expedite the development of liposome cargos and even their clinical translation for improving the prognosis of glioblastoma.

Lipid-hybrid cell-derived biomimetic functional materials: A state-of-the-art multifunctional weapon against tumors

Tumors are among the leading causes of death worldwide. Cell-derived biomimetic functional materials have shown great promise in the treatment of tumors. These materials are derived from cell membranes, extracellular vesicles and bacterial outer membrane vesicles and may evade immune recognition, improve drug targeting and activate antitumor immunity. However, their use is limited owing to their low drug-loading capacity and complex preparation methods. Liposomes are artificial bionic membranes that have high drug-loading capacity and can be prepared and modified easily. Although they can overcome the disadvantages of cell-derived biomimetic functional materials, they lack natural active targeting ability. Lipids can be hybridized with cell membranes, extracellular vesicles or bacterial outer membrane vesicles to form lipid-hybrid cell-derived biomimetic functional materials. These materials negate the disadvantages of both liposomes and cell-derived components and represent a promising delivery platform in the treatment of tumors. This review focuses on the design strategies, applications and mechanisms of action of lipid-hybrid cell-derived biomimetic functional materials and summarizes the prospects of their further development and the challenges associated with it.

Tumor targeted cancer membrane-camouflaged ultra-small Fe nanoparticles for enhanced collaborative apoptosis and ferroptosis in glioma

Glioma is recognized as the most common and aggressive primary brain tumor in adults. Owing to the occurrence of drug resistance and the failure of drug to penetrate the blood-brain barrier (BBB), there is no effective strategy for the treatment of glioma. The main objective of this study was to develop a biomimetic glioma C6 cell membrane (C6M) derived nanovesicles (DOX-FN/C6M-NVs) loaded with doxorubicin (DOX) and ultra-small Fe nanoparticles (FN) for accomplishing the effective brain tumor-targeted delivery of DOX and improving anti-cancer efficacy via inducing collaborative apoptosis and ferroptosis. The findings revealed that employing C6M-NVs as a carrier significantly improved the therapeutic efficacy by enabling evasion of immune surveillance, facilitating targeted drug delivery to tumor sites, and minimizing cardiotoxicity and adverse effects associated with DOX. DOX-FN/C6M-NVs exhibited more potent anti-tumor effects as compared with free DOX by promoting DOX-mediated apoptosis and accelerating ferroptosis via the mediation of FN. This study suggested that DOX-FN/C6M-NVs as the potential inducer of ferroptosis and apoptosis conferred effective tumor suppression in the treatment of glioma.

Cell membrane-based biomimetic vehicles for effective central nervous system target delivery: Insights and challenges

Central nervous system (CNS) disorders, including brain tumor, ischemic stroke, Alzheimer's disease, and Parkinson's disease, threaten human health. And the existence of the blood-brain barrier (BBB) hinders the delivery of drugs and the design of drug targeting delivery vehicles. Over the past decades, great interest has been given to cell membrane-based biomimetic vehicles since the rise of targeting drug delivery systems and biomimetic nanotechnology. Cell membranes are regarded as natural multifunction biomaterials, and provide potential for targeting delivery design and modification. Cell membrane-based biomimetic vehicles appear timely with the participation of cell membranes and nanoparticles, and raises new lights for BBB recognition and transport, and effective therapy with its biological multifunction and high biocompatibility. This review summarizes existing challenges in CNS target delivery and recent advances of different kinds of cell membrane-based biomimetic vehicles for effective CNS target delivery, and deliberates the BBB targeting mechanism. It also discusses the challenges and possibility of clinical translation, and presents new insights for development.

Cancer cell-mitochondria hybrid membrane coated Gboxin loaded nanomedicines for glioblastoma treatment

Glioblastoma (GBM) remains the most lethal malignant tumours. Gboxin, an oxidative phosphorylation inhibitor, specifically restrains GBM growth by inhibiting the activity of F₀F₁ ATPase complex V. However, its anti-GBM effect is seriously limited by poor blood circulation, the blood brain barrier (BBB) and non-specific GBM tissue/cell uptake, leading to insufficient Gboxin accumulation at GBM sites, which limits its further clinical application. Here we present a biomimetic nanomedicine (HM-NPs@G) by coating cancer cell-mitochondria hybrid membrane (HM) on the surface of Gboxin-loaded nanoparticles. An additional design element uses a reactive oxygen species responsive polymer to facilitate at-site Gboxin release. The HM camouflaging endows HM-NPs@G with unique features including good biocompatibility, improved pharmacokinetic profile, efficient BBB permeability and homotypic dual tumour cell and mitochondria targeting. The results suggest that HM-NPs@G achieve improved blood circulation (4.90 h versus 0.47 h of free Gboxin) and tumour accumulation (7.73% ID/g versus 1.06% ID/g shown by free Gboxin). Effective tumour inhibition in orthotopic U87MG GBM and patient derived X01 GBM stem cell xenografts in female mice with extended survival time and negligible side effects are also noted. We believe that the biomimetic Gboxin nanomedicine represents a promising treatment for brain tumours with clinical potential.

Reconstituted Lipid Nanoparticles from Cells/Tissues for Drug Delivery in Cancer

Nanomedicine represents a promising way to devise better drug delivery systems (DDSs), and the development of cell/tissue-based lipid carriers is a promising strategy. In this study, the author proposes the concept of reconstituted lipid nanoparticles (rLNPs) and offers a facile preparation method. The results demonstrated that the preparation of ultrasmall (∼20 nm) rLNPs can be highly reproducible from both cells (a mouse breast cancer cell line, 4T1) and tissue (mouse liver tissue). As a selected model platform, rLNPs derived from mouse liver tissue can be further labeled with imaging molecules (indocyanine green and coumarin 6) and modified with targeting moiety (biotin). Moreover, rLNPs were proved to be highly biocompatible and able to load various drugs, such as doxorubicin hydrochloride (Dox) and curcumin (Cur). Most importantly, Dox-loaded rLNPs (rLNPs/Dox) exerted good in vitro and in vivo anticancer performances. Therefore, rLNPs might be a potential versatile carrier for the construction of different DDSs and treatment of a variety of diseases.

Macrophage cell membrane infused biomimetic liposomes for glioblastoma targeted therapy

Glioblastoma (GBM) is a highly aggressive malignant brain tumor currently without an effective treatment. Inspired by the recent advances in cell membrane biomimetic nanocarriers and by the key role of macrophages in GBM pathology, we developed macrophage membrane liposomes (MML) for GBM targeting. For the first time, it was assessed the role of macrophage polarization states in the effectiveness of these drug delivery systems. Interestingly, we observed that MML derived from M2 macrophages (M2 MML) presents higher uptake and increased delivery of the anticarcinogenic drug doxorubicin compared to M1 macrophage-derived nanocarriers (M1 MML) and control liposomes (CL). Moreover, the lowest uptake by macrophages of MML reveals promising immune escaping properties. Notably, M2 macrophages unveiled a higher expression of integrin CD49d, a crucial protein involved in the bilateral communication of macrophages with tumor cells. Therefore, our findings suggest the potential of using M2 macrophage membranes to develop novel nanocarriers targeting GBM.

Getting drugs to the brain: advances and prospects of organic nanoparticle delivery systems for assisting drugs to cross the blood-brain barrier

The blood-brain barrier (BBB) plays an irreplaceable role in protecting the central nervous system (CNS) from bloodborne pathogens. However, the BBB complicates the treatment of CNS diseases because it prevents almost all therapeutic drugs from getting into the CNS. With the growing understanding of the physiological characteristics of the BBB and the development of nanotechnology, nanomaterial-based drug delivery systems have become promising tools for delivering drugs across the BBB to the CNS. Herein, we systematically summarize the recent progress in organic-nanoparticle delivery systems for treating CNS diseases and evaluate their mechanisms in overcoming the BBB with the aim to provide a comprehensive understanding of the advantages, disadvantages, and challenges of organic nanoparticles in delivering drugs across the BBB. This review may inspire new research ideas and directions for applying nanotechnology to treat CNS diseases.

Micro-Nanocarriers Based Drug Delivery Technology for Blood-Brain Barrier Crossing and Brain Tumor Targeting Therapy

The greatest obstacle to using drugs to treat brain tumors is the blood-brain barrier (BBB), making it difficult for conventional drug molecules to enter the brain. Therefore, how to safely and effectively penetrate the BBB to achieve targeted drug delivery to brain tumors has been a challenging research problem. With the intensive research in micro- and nanotechnology in recent years, nano drug-targeted delivery technologies have shown great potential to overcome this challenge, such as inorganic nanocarriers, organic polymer-carriers, liposomes, and biobased carriers, which can be designed in different sizes, shapes, and surface functional groups to enhance their ability to penetrate the BBB and targeted drug delivery for brain tumors. In this review, the composition and overcoming patterns of the BBB are detailed, and then the hot research topics of drug delivery carriers for brain tumors in recent years are summarized, and their mechanisms of action on the BBB and the factors affecting drug delivery are described in detail, and the effectiveness of targeted therapy for brain tumors is evaluated. Finally, the challenges and dilemmas in developing brain tumor drug delivery systems are discussed, which will be promising in the future for targeted drug delivery to brain tumors based on micro-nanocarriers technology.

Brain Co-Delivery of Temozolomide and Cisplatin for Combinatorial Glioblastoma Chemotherapy

Glioblastoma (GBM) is an intractable malignancy with high recurrence and mortality. Combinatorial therapy based on temozolomide (TMZ) and cisplatin (CDDP) shows promising potential for GBM therapy in clinical trials. However, significant challenges include limited blood-brain-barrier (BBB) penetration, poor targeting of GBM tissue/cells, and systemic side effects, which hinder its efficacy in GBM therapy. To surmount these challenges, new GBM-cell membrane camouflaged and pH-sensitive biomimetic nanoparticles (MNPs) inspired by the fact that cancer cells readily pass the BBB and localize with homologous cells, are developed. This study's results show that MNPs can efficiently co-load TMZ and CDDP, transport these across the BBB to specifically target GBM. Incorporation of pH-sensitive polymer then allows for controlled release of drug cargos at GBM sites for combination drug therapy. Mice bearing orthotopic U87MG or drug-resistant U251^R GBM tumor and treated with MNPs@TMZ+CDDP show a potent anti-GBM effect, greatly extending the survival time relative to mice receiving single-drug loaded nanoparticles. No obvious side effects are apparent in histological analyses or blood routine studies. Considering these results, the study's new nanoparticle formulation overcomes multiple challenges currently limiting the efficacy of combined TMZ and CDDP GBM drug therapy and appears to be a promising strategy for future GBM combinatorial chemotherapy.

Biomimetic semiconducting polymer dots for highly specific NIR-II fluorescence imaging of glioma

Glioma with very short medium survival time consists of 80% of primary malignant types of brain tumors. The unique microenvironment such as the existence of the blood-brain barrier (BBB) makes the glioma theranostics exhibit low sensitivity in diagnosis, a poor prognosis and low treatment efficacy. Therefore, the development of multifunctional nanoplatform that can cross BBB and target the glioma is essential for the high-sensitivity detection and ablation of cancer cells. In this study, C6 cell membrane-coated conjugated polymer dots (Pdots-C6) were constructed for targeted glioma tumor detection. As a new kind of biomimetic and biocompatible nanoprobes, Pdots-C6 preserve the complex biological functions of natural cell membranes while possessing physicochemical properties for NIR-II fluorescence imaging of glioma. After encapsulating C6 cell membrane on the surface of conjugated Pdots, Pdots-C6 exhibited the most favorable specific targeting capabilities in vitro and in vivo. In particular, this pilot study demonstrates that biomimetic nanoparticles offer a potential tool to enhance specific targeting to the brain, hence improving glioma tumor detection accuracy.

Biomimetic multifunctional persistent luminescence nanoprobes for long-term near-infrared imaging and therapy of cerebral and cerebellar gliomas

Glioma is the most common malignant primary brain tumor, and the accurate diagnosis of glioma has always been a challenge. Moreover, cerebellar glioma, which is difficult to be detected by magnetic resonance imaging, is not usually diagnosed until after the appearance of clinical symptoms. In this study, TRZD, a near-infrared (NIR) persistent luminescence (PL) nanoparticle with a dual function of imaging and therapy, was synthesized based on ZnGa₂O₄:Cr³⁺,Sn⁴⁺. TRZD showed excellent rechargeable NIR PL for more than 30 hours in vivo with good tissue penetration for long-term autofluorescence-free imaging. The tumor growth of both the subcutaneous and orthotropic glioma models was significantly inhibited by TRZD. This is the first-time approach using NIR PL nanoprobes for both diagnosis and therapy of glioma. This is also the first-time report of nanotechnology-based diagnosis and therapy of cerebellar gliomas. This study offers a highly promising multifunctional nanoparticle for theranostics of a wide range of brain diseases.

Biomimetic and cell-based nanocarriers - New strategies for brain tumor targeting

In the last two decades no significant advances were achieved in the treatment of the most frequent and malignant types of brain tumors. The main difficulties in achieving progress are related to the incapacity to deliver drugs in therapeutic amounts into the central nervous system and the associated severe side effects. Indeed, to obtain effective treatments, the drugs should be able to cross the intended biological barriers and not being inactivated before reaching the specific therapeutic target. To overcome these challenges the development of synthetic nanocarriers has been widely explored for brain tumor treatment but unfortunately with no clinical translation until date. The use of cell-derived nanocarriers or biomimetic nanocarriers has been studied in the last few years, considering their innate bio-interfacing properties. The ability to carry therapeutic agents and a higher selectivity towards brain tumors would bring new hope for the development of safe and effective treatments. In this review, we explore the biological barriers that need to be crossed for effective delivery in brain tumors, and the types and properties of cell-based nanocarriers (extracellular vesicles and cell-membrane coated nanocarriers) currently under investigation.

Delivery of pOXR1 through an injectable liposomal nanoparticle enhances spinal cord injury regeneration by alleviating oxidative stress

Oxidation resistance 1 (OXR1) is regarded as a critical regulator of cellular homeostasis in response to oxidative stress. However, the role of OXR1 in the neuronal response to spinal cord injury (SCI) remains undefined. On the other hand, gene therapy for SCI has shown limited success to date due in part to the poor utility of conventional gene vectors. In this study, we evaluated the function of OXR1 in SCI and developed an available carrier for delivering the OXR1 plasmid (pOXR1). We found that OXR1 expression is remarkably increased after SCI and that this regulation is protective after SCI. Meanwhile, we assembled cationic nanoparticles with vitamin E succinate-grafted ε-polylysine (VES-g-PLL) (Nps). The pOXR1 was precompressed with Nps and then encapsulated into cationic liposomes. The particle size of pOXR1 was compressed to 58 nm, which suggests that pOXR1 can be encapsulated inside liposomes with high encapsulation efficiency and stability to enhance the transfection efficiency. The agarose gel results indicated that Nps-pOXR1-Lip eliminated the degradation of DNA by DNase I and maintained its activity, and the cytotoxicity results indicated that pOXR1 was successfully transported into cells and exhibited lower cytotoxicity. Finally, Nps-pOXR1-Lip promoted functional recovery by alleviating neuronal apoptosis, attenuating oxidative stress and inhibiting inflammation. Therefore, our study provides considerable evidence that OXR1 is a beneficial factor in resistance to SCI and that Nps-Lip-pOXR1 exerts therapeutic effects in acute traumatic SCI.

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OXR1 is upregulated after SCI and may provide a protective effect in response to neural injury.

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OXR1 plasmid is condensed by VES-g-PLL micelles and then encapsulated into cationic liposomes.

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Liposome complexes significantly enhance the OXR1 protein expression in vivo and in vitro.

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Overexpressed OXR1 relieving oxidative stress after SCI through Nrf-2/HO-1 pathway.

Environmentally Self-Adaptative Nanocarriers Suppress Glioma Proliferation and Stemness via Codelivery of shCD163 and Doxorubicin

Gliomas-devastating intracranial tumors with a dismal outcome-are in dire need of innovative treatment. Although nanodrugs have been utilized as a target therapy for certain types of solid tumors, their therapeutic effects in gliomas are limited due to the complications of the systemic circulation, blood-brain barrier (BBB), and specific glioma environment. Thus, we aimed to establish a nanoliposome adaptable to different environments by codelivery of shCD163 and doxorubicin (DOX) to treat gliomas. In this study, we first synthesized pH-sensitive DSPE-cRGD-Hz-PEG₂₀₀₀ to form an environmentally self-adaptative nanoliposome (cRGD-DDD Lip) via a thin film method. We used in vitro BBB models, in vitro cell uptake experiments, and in vivo biodistribution assays to confirm the long circulation time and low cell uptake of the cRGD-DDD Lip as a result of the poly(ethylene glycol) (PEG) shell of cRGD-DDD Lip in the neutral pH systemic circulation. Moreover, the cRGD-DDD Lip bypassed the BBB and attached to the intracranial glioma following the removal of the PEG shell and the exposure of cRGD to the weakly acidic tumor microenvironment. We further assembled the shCD163/DOX@cRGD-DDD Lip through cRGD-DDD Lip loading of shCD163 and DOX. In vitro, cell proliferation and self-renewal of glioma cells were inhibited by the shCD163/DOX@cRGD-DDD Lip due to the toxicity of DOX and the suppression of shCD163 via the CD163 pathway. In vivo, the shCD163/DOX@cRGD-DDD Lip disturbed the progression of in situ gliomas by inhibiting the growth and stemness of glioma cells and prevented the recurrence of gliomas after resection. In conclusion, the cRGD-DDD Lip may be a promising nanodrug-loading platform to cope with different environments and the shCD163/DOX@cRGD-DDD Lip may potentially be a novel nanodrug for glioma therapy.