CAR-neutrophil mediated delivery of tumor-microenvironment responsive nanodrugs for glioblastoma chemo-immunotherapy

Challenges and material innovations in drug delivery to central nervous system tumors

Central nervous system (CNS) tumors, encompassing a diverse array of neoplasms in the brain and spinal cord, pose significant therapeutic challenges due to their intricate anatomy and the protective presence of the blood-brain barrier (BBB). The primary treatment obstacle is the effective delivery of therapeutics to the tumor site, which is hindered by multiple physiological, biological, and technical barriers, including the BBB. This comprehensive review highlights recent advancements in material science and nanotechnology aimed at surmounting these delivery challenges, with a focus on the development and application of nanomaterials. Nanomaterials emerge as potent tools in designing innovative drug delivery systems that demonstrate the potential to overcome the limitations posed by CNS tumors. The review delves into various strategies, including the use of lipid nanoparticles, polymeric nanoparticles, and inorganic nanoparticles, all of which are engineered to enhance drug stability, BBB penetration, and targeted tumor delivery. Additionally, this review highlights the burgeoning role of theranostic nanoparticles, integrating therapeutic and diagnostic functionalities to optimize treatment efficacy. The exploration extends to biocompatible materials like biodegradable polymers, liposomes, and advanced material-integrated delivery systems such as implantable drug-eluting devices and microfabricated devices. Despite promising preclinical results, the translation of these material-based strategies into clinical practice necessitates further research and optimization.

Tumor microenvironment pH-responsive size-transformable peptide self-assembling nanocarriers for tumor-specific treatment

Peptide-based drug carriers with exceptional biodegradability offer promising avenues for tumor-targeted therapy. Nonetheless, almost all existing drug carriers harness receptor recognition to target tumors, which ultimately fall short in addressing tumor heterogeneity. Such a strategy requires intricate chemical modifications for carriers to selectively bind to specific receptors. While these modifications may induce long-term toxicity, tumor receptors are not absolutely specific but also exist in normal cells. Thus, precision therapeutic agents may inadvertently harm healthy cells as well. Tumors possess a distinctive weak acidic (pH 6.0-6.8) tumor microenvironment (TME) that contrasts with normal tissues (pH ~7.4). Hence, we developed a TME pH-triggered multilevel self-assembling peptide with simple modifications. The drug-encapsulating self-assembled peptide is size transformable from aggregates (~1.56 μm) at pH 7.4 to positively charged nanomicelles (~100 nm) at an acidic TME by protonation, which avoids being taken up by normal cells but could readily enter tumor cells, allowing TME pH-triggered tumor-specific therapy. This study establishes a breaking strategy of using peptide for TME-based tumor-specific treatment and advances the medical applications of peptide nanomaterials.

Enhancing immunotherapy with tumour-responsive nanomaterials

The targeted delivery of immunotherapies to tumours using tumour-responsive nanomaterials is a promising area of cancer research with the potential to address the limitations of systemic administration such as on-target off-tumour toxicities and a lack of activity owing to the immunosuppressive tumour microenvironment (TME). Attempts to address these challenges include the design and functionalization of nanomaterials capable of releasing their cargoes in response to specific TME characteristics, thus facilitating the targeted delivery of immune-checkpoint inhibitors, cytokines, mRNAs, vaccines and, potentially, chimaeric antigen receptors as well as of agents that modulate the extracellular matrix and induce immunogenic cell death. In this Review, we describe these various research efforts in the context of the dynamic properties of the TME, such as pH, reductive conditions, reactive oxygen species, hypoxia, specific enzymes, high levels of ATP and locoregional aspects, which can be leveraged to enhance the specificity and efficacy of nanomaterial-based immunotherapies. Highlighting preclinical successes and ongoing clinical trials, we evaluate the current landscape and potential of these innovative approaches. We also consider future research directions as well as the most important barriers to successful clinical translation, emphasizing the transformative potential of tumour-responsive nanomaterials in overcoming the barriers that limit the activity of traditional immunotherapies, thus improving patient outcomes.

DNA scaffold-framed natural killer cell with programmed drug release for chemo-adoptive cell therapy

Choosing appropriate delivery system for chemotherapeutic drugs as well as arranging the time spots for adoptive cells administrations is the key to achieve efficient combined chemo-adoptive cell therapy. Tumor-homing character makes adoptive immune cells appropriate targeting delivery carriers, but they are rarely used for chemtoxic payloads considering payloads internalization during administration which impairs adoptive cells. Herein, we frame adoptive NK cells using DNA scaffold with chemotherapeutic payloads fastened exterior, and achieves time-programmed drugs release and NK cell decapsulation to minimize side effects and enhance therapeutic effect. IL-21 nanoparticles are prepared by conjugating cytokine IL-21 with a GSH cleavable linker and act as anchor points for DNA scaffold assembly. Chemotherapeutic payloads are prepared by loading DOX/verapamil drugs to PLGA nanoparticles (PLGAdrugs NPs), and connected to the exterior of DNA scaffold with a ROS cleavable linker. Porous DNA scaffold protects NK cells functions from impairing by chemotherapeutic payloads, while guarantees efficient communication of NK cells with exterior environment to keep tumor homing capability. Reactive oxygen species (ROS) in tumor microenvironment releases PLGAdrugs NPs to perform chemotherapy, which subsequently generates a reductive environment to detach DNA scaffold for NK cell and IL-21 release to achieve combined chemo-adoptive cell therapy with enhanced therapeutic efficiency.

Targeted editing of CCL5 with CRISPR-Cas9 nanoparticles enhances breast cancer immunotherapy

Breast cancer remains one of the leading causes of cancer-related mortality among women worldwide. Immunotherapy, a promising therapeutic approach, often faces challenges due to the immunosuppressive tumor microenvironment. This study explores the innovative use of CRISPR-Cas9 technology in conjunction with FCPCV nanoparticles to target and edit the C-C Motif Chemokine Ligand 5 (CCL5) gene, aiming to improve the efficacy of breast cancer immunotherapy. Single-cell RNA sequencing (scRNA-seq) and TCGA-BRCA data identified CCL5 as a key immune-related gene in breast cancer. Using CRISPR-Cas9, sgRNA targeting CCL5 was designed and delivered to breast cancer cells and humanized mouse models via FCPCV nanoparticles. In vitro experiments demonstrated that FCPCV nanoparticles effectively silenced CCL5, enhanced CD8+ T cell activity, and increased the production of cytokines such as IFN-γ, TNF-α, and GZMB. In vivo studies revealed significant tumor suppression, improved immune microenvironment, and increased CD8+/CD4+ ratios in treated mice, without notable toxic side effects. These findings highlight the potential of CRISPR-Cas9 nanoparticle-mediated gene editing as a novel strategy for enhancing breast cancer immunotherapy, providing a new direction for personalized and effective cancer treatment.

Targeting HSP90AA1 to overcome multiple drug resistance in breast cancer using magnetic nanoparticles loaded with salicylic acid

Multiple drug resistance (MDR) remains a major obstacle in effective breast cancer chemotherapy. This study explores the role of HSP90AA1 in driving MDR and evaluates the potential of magnetic nanoparticles (Fe3O4@SA) loaded with salicylic acid (SA) to counteract drug resistance. A comprehensive screening of 200 SA-related target genes identified nine core genes, including HSP90AA1. Pharmacophore analysis revealed that SA interacts with HSP90AA1, a key regulator of mitochondrial K+ channels. Fe3O4@SA nanoparticles demonstrated efficient cellular uptake and lysosomal escape, markedly improving the chemosensitivity of resistant breast cancer cells and promoting apoptosis. In vivo experiments further confirmed the anticancer efficacy of Fe3O4@SA, highlighting its potential as a promising therapeutic strategy to overcome MDR in breast cancer.

Novel neutrophil targeting platforms in treating Glioblastoma: Latest evidence and therapeutic approaches

Glioblastoma (GBM) is the most aggressive and lethal type of primary brain tumor, characterized by its rapid growth, resistance to conventional therapies, and a highly immunosuppressive tumor microenvironment (TME). Recent studies have highlighted the critical role of neutrophils in the progression of GBM, where they contribute to tumor growth, invasion, and treatment resistance. As a result, neutrophils have emerged as a promising target for therapeutic intervention in GBM. Various strategies are being investigated to specifically target neutrophils within the GBM environment, including using small molecules, antibodies, and nanoparticle-based methods. These approaches aim to regulate neutrophils' recruitment, activation, and functions. This study reviews the latest findings regarding the involvement of neutrophils in GBM, explores potential techniques targeting neutrophils for therapeutic purposes, and discusses current clinical studies and prospects in this rapidly evolving field. By studying the diverse functions of neutrophils in GBM, these innovative therapeutic strategies can help address some of the most significant challenges in treating this malignancy.

Opportunities to Modulate Tumor Ecosystem Toward Successful Glioblastoma Immunotherapy

Over the past decade, the failure of multiple clinical trials has confirmed the need for a systematic and comprehensive understanding of glioblastoma (GBM). Current immunotherapies aiming to harness the immune system to achieve anti-tumor effects remain largely ineffective, highlighting the complexities of the GBM microenvironment. However, our recent understanding of immune niches within the central nervous system provides both opportunities and challenges in translating these insights into successful immunotherapy implementation. We discuss these strategies, including targeting multiple antigens within the heterogeneous GBM microenvironment, identifying new druggable targets to abrogate immunosuppression, and understanding niche-specific immune cell functionality to modulate tumor-immune-stroma interactions.

Targeting gut microbiota: a potential therapeutic approach for tumor microenvironment in glioma

Glioma, being one of the malignant tumors with the highest mortality rate globally, has an unclear pathogenesis, and the existing treatment effects still have certain limitations. The tumor microenvironment (TME) plays an important role in the occurrence, development, and recurrence of glioma. As one of the important regulatory factors of TME, the gut microbiota can regulate the progression of glioma not only by interacting with the brain through the brain-gut axis but also by influencing the tumor immune microenvironment (TIME) and inflammatory microenvironment. Recent studies have identified the gut microbiota and TME as potential therapeutic targets for glioma. This paper aims to summarize the role of the gut microbiota in TME, the association between them and glioma, and the potential of developing new intervention measures by targeting the gut microbiota. Understanding the involvement process of the gut microbiota in glioma may pave the way for the development of effective treatment methods that can regulate TME and prevent disease progression.

Are monocytes a preferable option to develop myeloid cell-based therapies for solid tumors?

In the last two decades, novel and promising cell-based therapies have populated the treatment landscape for haematological tumors. However, commonly exploited T and NK cell-based therapies show limited applicability to solid tumors. This is mainly given by the impaired tumor trafficking capability and limited effector activity of these cells within a highly immunosuppressive tumor microenvironment. Myeloid cells spontaneously home to tumors and can thus be reprogrammed and/or engineered to directly attack tumor cells or locally and selectively deliver therapeutically relevant payloads that may improve the efficacy of immunotherapy against difficult-to-access solid tumors. In the context of myeloid cell-based therapies, adoptive transfer of monocytes has often been overshadowed by infusion of differentiated macrophages or hematopoietic stem cell transplantation despite their promising therapeutic potential. Here, we summarize the recent improvements and benefits of using monocytes for the treatment of solid tumors, their current clinical applications and the challenges of their use as well as some possible strategies to overcome them.

Harnessing myeloid cells in cancer

Cancer-associated myeloid cells due to their plasticity play dual roles in both promoting and inhibiting tumor progression. Myeloid cells with immunosuppressive properties play a critical role in anti-cancer immune regulation. Cells of different origin, such as tumor associated macrophages (TAMs), tumor associated neutrophils (TANs), myeloid derived suppressor cells (also called MDSCs) and eosinophils are often expanded in cancer patients and significantly influence their survival, but also the outcome of anti-cancer therapies. For this reason, the variety of preclinical and clinical studies to modulate the activity of these cells have been conducted, however without successful outcome to date. In this review, pro-tumor activity of myeloid cells, myeloid cell-specific therapeutic targets, in vivo studies on myeloid cell re-polarization and the impact of myeloid cells on immunotherapies/genetic engineering are addressed. This paper also summarizes ongoing clinical trials and the concept of chimeric antigen receptor macrophage (CAR-M) therapies, and suggests future research perspectives, offering new opportunities in the development of novel clinical treatment strategies.

Tumor Metastasis: Mechanistic Insights and Therapeutic Intervention

Metastasis remains a leading cause of cancer‐related deaths, defined by a complex, multi‐step process in which tumor cells spread and form secondary growths in distant tissues. Despite substantial progress in understanding metastasis, the molecular mechanisms driving this process and the development of effective therapies remain incompletely understood. Elucidating the molecular pathways governing metastasis is essential for the discovery of innovative therapeutic targets. The rapid advancements in sequencing technologies and the expansion of biological databases have significantly deepened our understanding of the molecular drivers of metastasis and associated drug resistance. This review focuses on the molecular drivers of metastasis, particularly the roles of genetic mutations, epigenetic changes, and post‐translational modifications in metastasis progression. We also examine how the tumor microenvironment influences metastatic behavior and explore emerging therapeutic strategies, including targeted therapies and immunotherapies. Finally, we discuss future research directions, stressing the importance of novel treatment approaches and personalized strategies to overcome metastasis and improve patient outcomes. By integrating contemporary insights into the molecular basis of metastasis and therapeutic innovation, this review provides a comprehensive framework to guide future research and clinical advancements in metastatic cancer.

TLR7/8 signaling activation enhances the potency of human pluripotent stem cell-derived eosinophils in cancer immunotherapy for solid tumors

BACKGROUND

Efficient tumor T-cell infiltration is crucial for the effectiveness of T-cell-based therapies against solid tumors. Eosinophils play crucial roles in recruiting T cells in solid tumors. Our group has previously generated induced eosinophils (iEOs) from human pluripotent stem cells and exhibited synergistic efficacy with CAR-T cells in solid tumor inhibition. However, administrated eosinophils might influx into inflammatory lungs, posing a potential safety risk. Mitigating the safety concern and enhancing efficacy is a promising development direction for further application of eosinophils.

METHODS

We developed a new approach to generate eosinophils with enhanced potency from human chemically reprogrammed induced pluripotent stem cells (hCiPSCs) with the Toll-like receptor (TLR) 7/8 signaling agonist R848.

RESULTS

R848-activated iEOs (R-iEOs) showed significantly decreased influx to the inflamed lungs, indicating a lower risk of causing airway disorders. Furthermore, these R-iEOs had enhanced anti-tumor functions, preferably accumulated at tumor sites, and further increased T-cell infiltration. The combination of R-iEOs and CAR-T cells suppressed tumor growth in mice. Moreover, the chemo-trafficking signaling increased in R-iEOs, which may contribute to the decreased lung influx of R-iEOs and the increased tumor recruitment of T cells.

CONCLUSION

Our study provides a novel approach to alleviate the potential safety concerns associated with eosinophils while increasing T-cell infiltration in solid tumors. This finding offers a prospective strategy for incorporating eosinophils to improve CAR-T-cell immunotherapy for solid tumors in the future.

Yiqi Huayu Jiedu Decoction reduces colorectal cancer liver metastasis by promoting N1 neutrophil chemotaxis

Objective

To observe the inhibitory effect and potential mechanism of Yiqi Huayu Jiedu Decoction (YHJD) on liver metastasis of colorectal cancer (CRC).

Methods

We compared the changes of liver weight and liver index before and after YHJD treatment in CRC liver metastasis mouse models. HE staining was employed to observe the pathological changes in mouse liver tissue sections. Flow cytometry was used to analyze the number and marker of neutrophils treated with YHJD. Transcriptomics, proteomics, and multiplex cytokine array analyses were conducted to further verify the role of YHJD on CXCL1. Differential gene analysis was performed to further explore the mechanism by which YHJD inhibits liver metastasis of CRC.

Results

Animal studies demonstrated that YHJD reduces liver metastases. Flow cytometry results revealed that YHJD promotes N1 neutrophils in liver. Combining multi-omics and multiple cytokine arrays, we observed a significant increase in the expression of CXCL1 in the liver and plasma. GO and KEGG enrichment analyses indicated that YHJD may regulate the chemotaxis of neutrophils to inhibit the liver metastasis of CRC by participating in the regulation of cell adhesion molecule binding, adhesion protein binding, and multiple metabolic pathways.

Conclusions

YHJD inhibits CRC liver metastasis by upregulating CXCL1, thereby promoting N1 neutrophil chemotaxis towards the liver, and concurrently raising the expression of N1 neutrophil markers.

Efficient Photosensitizer Delivery by Neutrophils for Targeted Photodynamic Therapy of Glioblastoma

Background/Objectives: Glioblastoma (GBM) is the deadliest type of brain tumor and photodynamic therapy (PDT) is a promising treatment modality of GBM. However, insufficient photosensitizer distribution in the GBM critically limits the success of PDT. To address this obstacle, we propose tumoritropic neutrophils (NE) as active carriers for photosensitizer delivery to achieve GBM-targeted PDT. Methods: Isolated mouse NE were loaded with functionalized hexagonal boron nitride nanoparticles carrying the photosensitizer chlorin e6 (BNPD-Ce6). In vitro experiments were conducted to determine drug release from the loaded NE (BNPD-Ce6@NE) to mouse GBM cells and consequential photo-cytotoxicity. In vivo experiments were performed on mice bearing intracranial graft GBMs to demonstrate GBM-targeted drug delivery and the efficacy of anti-GBM PDT mediated by BNPD-Ce6@NE. Results: BNPD-Ce6@NE displayed good viability and migration ability, and rapidly released BNPD-Ce6 to co-cultured mouse GBM cells, which then exhibited marked reactive oxygen species (ROS) generation and cytotoxicity following 808 nm laser irradiation (LI). In the in vivo study, a single intravenous bolus injection of BNPD-Ce6@NE resulted in pronounced Ce6 distribution in intracranial graft GBMs 4 h post injection, which peaked around 8 h post injection. A PDT regimen consisting of multiple intravenous BNPD-Ce6@NE injections each followed by one extracranial tumor-directed LI 8 h post injection significantly slowed the growth of intracranial graft GBMs and markedly improved the survival of host animals. Histological analysis revealed massive tumor cell damage and NE infiltration in the PDT-treated GBMs. Conclusions: NE are efficient carriers for GBM-targeted photosensitizer delivery to achieve efficacious anti-GBM PDT.

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.

Forward programming of hPSCs to neutrophils using chemically defined media

Polymorphonuclear neutrophils (PMNs), the most abundant leukocytes circulating in human blood, are pivotal players in the innate immune system. In recent years, PMNs have gained increasing recognition for their significant involvement in the pathogenesis of a wide array of human diseases, including sepsis, pulmonary conditions, autoimmune disorders, and various cancers. Due to their terminally differentiated state, PMNs possess a short lifespan and exhibit limited proliferative potential, which makes continuous replenishment from the bone marrow essential for maintaining immune homeostasis. This demand underscores the need for efficient, reliable, and robust methods of PMN production. In this study, we evaluated three forward programming protocols and one directed differentiation protocol aimed at generating PMNs from human pluripotent stem cells (hPSCs). We analyzed not only their differentiation efficiency but also the transcriptomic profiles and functional capabilities of the resulting PMNs. Our findings revealed that both the forward programming method and the directed differentiation approach can successfully generate functional PMNs. Furthermore, by fine-tuning the culture media at various stages during forward programming, we identified an optimal protocol that significantly enhances hematopoietic differentiation potential and promotes the functional maturity of the neutrophils.

Brain-targeting drug delivery systems: The state of the art in treatment of glioblastoma

Glioblastoma (GBM) is the most prevalent primary malignant brain tumor, characterized by a high mortality rate and a poor prognosis. The blood-brain barrier (BBB) and the blood-tumor barrier (BTB) present significant obstacles to the efficacy of tumor-targeted pharmacotherapy, thereby impeding the therapeutic potential of numerous candidate drugs. Targeting delivery of adequate doses of drug across the BBB to treat GBM has become a prominent research area in recent years. This emphasis has driven the exploration and evaluation of diverse technologies for GBM pharmacotherapy, with some already undergoing clinical trials. This review provides a thorough overview of recent advancements and challenges in targeted drug delivery for GBM treatment. It specifically emphasizes systemic drug administration strategies to assess their potential and limitations in GBM treatment. Furthermore, this review highlights promising future research directions in the development of intelligent drug delivery systems aimed at overcoming current challenges and enhancing therapeutic efficacy against GBM. These advancements not only support foundational research on targeted drug delivery systems for GBM but also offer methodological approaches for future clinical applications.

Pluripotent stem cell-based immunotherapy: advances in translational research, cell differentiation, and gene modifications

Cell-based immunotherapy, recognized as living drugs, is revolutionizing clinical treatment to advanced cancer and shaping the landscape of biomedical research for complex diseases. The differentiation of human pluripotent stem cells (PSCs) emerges as a novel platform with the potential to generate an unlimited supply of therapeutic immune cells, especially when coupled with gene modification techniques. PSC-based immunotherapy is expected to meet the vast clinical demand for living drugs. Here, we examine recent preclinical and clinical advances in PSC-based immunotherapy, focusing on PSC gene modification strategies and differentiation methods for producing therapeutic immune cells. We also discuss opportunities in this field and challenges in cell quality and safety and stresses the need for further research and transparency to unlock the full potential of PSC immunotherapies.

Adoptive Cell Therapy from the Dish: Potentiating Induced Pluripotent Stem Cells

Background

The clinical success of autologous adoptive cell therapy (ACT) is substantial but wide application is challenged by the quality and quantity of the patient's immune cells and the need for personalized manufacturing processes. Induced pluripotent stem cells (iPSCs) can be differentiated into immune effectors and thus provide an alternative, allogeneic cell source for ACT. Here, we compare iPSC-derived immune effectors to their PBMC-derived counterparts and review iPSC-derived ACT products currently under preclinical and clinical development.

Summary

iPSC-derived T cells, NK cells, macrophages, and neutrophils largely mimic their PBMC-derived counterparts in terms of cell-surface marker expression and cytotoxic effector functions. iPSC-derived immune effectors can be engineered with chimeric antigen receptors and other activating receptors to redirect their cytotoxic potential specifically to tumor-associated antigens (TAAs). However, several differences between iPSC- and PBMC-derived immune effectors remain and have inspired additional engineering strategies to enhance the antitumor capacity of iPSC-derived immune effectors.

Key Messages

iPSCs can be engineered to facilitate the generation of immune effectors with homogenous specificity for TAAs and enhanced effector functions. TAA-specific and functionally enhanced iPSC-derived T and NK cells are currently undergoing clinical evaluation in phase 1 trials. Engineered iPSC-derived macrophages and neutrophils are in preclinical development.

Ultrasonic-Controlled Drug Release Prevents Protumorigenic Transition and Improves Sequential Targeting Effect to Enhance Treatment of Residual Hepatocellular Carcinoma

Insufficient radio-frequency ablation (IRFA) of hepatocellular carcinoma accelerates the recurrence of residual tumor, leading to a poor prognosis. Neutrophils (NEs), as the initial leukocytes to infiltrate the IRFA-associated inflammatory area, were utilized as drug carriers due to their inherent chemotactic properties for targeted delivery of chemotherapy drugs to the inflammatory site where residual tumor persists post-IRFA. Previous research has highlighted that the immunosuppressive cytokines in the tumor microenvironment could promote the transition of NEs into a protumorigenic phenotype. However, it is unclear whether NEs used as drug delivery carriers undergo similar changes and how this transition affects treatment effectiveness. Here, we present novel findings demonstrating the phenotypic transition of NEs in the residual tumor microenvironment from an antitumorigenic to a protumorigenic state following IRFA treatment. More critically, we found for the first time that NE carriers undergo a comparable phenotypic transition in the residual tumor, thereby attenuating the therapeutic outcome. Ingeniously, coloading NE carriers with perfluorohexane not only enabled ultrasound imaging but also facilitated spatiotemporally controllable drug release through ultrasound irradiation, thus preventing the protumorigenic transition of NE carriers and maintaining an inflammatory microenvironment at the residual tumor zone. This significantly improved the sequential targeting effect of NE carriers and ultimately enhanced the treatment of residual tumor post-IRFA. Our study provided novel insights into the modulatory role of the immune microenvironment on the phenotypic transition of live NE carriers in the drug delivery system and presented a strategy to prevent adverse effects and enhance residual tumor treatment.

Neutrophil Engulfment in Cancer: Friend or Foe?

Neutrophils, the most abundant circulating white blood cells, are essential for the initial immune response to infection and injury. Emerging research reveals a dualistic function of neutrophils in cancer, where they can promote or inhibit tumor progression. This dichotomy is influenced by the tumor microenvironment, with neutrophils capable of remodeling the extracellular matrix, promoting angiogenesis, or alternatively inducing cancer cell death and enhancing immune responses. An intriguing yet poorly understood aspect of neutrophil-cancer interactions is the phenomenon of neutrophil engulfment by cancer cells, which has been observed across various cancers. This process, potentially mediated by LC3-associated phagocytosis (LAP), raises questions about whether it serves as a mechanism for immune evasion or contributes to tumor cell death through pathways like ferroptosis. This review examines current knowledge on neutrophil development, their roles in cancer, and the mechanisms of LAP in neutrophil engulfment by tumor cells. We discuss how manipulating LAP impacts cancer progression and may represent a therapeutic strategy. We also explore neutrophils' potential as delivery vehicles for cancer therapeutic agents. Understanding the complex functions of tumor-associated neutrophils (TANs) and the molecular mechanisms underlying LAP in cancer may open new avenues for effective therapeutic interventions and mitigate potential risks.

Adaptations of neutrophils in cancer

There is a renewed interest in neutrophil biology, largely instigated by their prominence in cancer. From an immunologist's perspective, a conceptual breakthrough is the realization that prototypical inflammatory, cytotoxic leukocytes can be tamed to promote the survival and growth of other cells. This has sparked interest in defining the biological principles and molecular mechanisms driving the adaptation of neutrophils to cancer. Yet, many questions remain: is this adaptation mediated by reprogramming mature neutrophils inside the tumoral mass, or rather by rewiring granulopoiesis in the bone marrow? Why, in some instances, are neutrophils beneficial and in others detrimental to cancer? How many different functional programs can be induced in neutrophils by tumors, and is this dependent on the type of tumor? This review summarizes what we know about these questions and discusses therapeutic strategies based on our incipient knowledge of how neutrophils adapt to cancer.

Collagen Hydrogel Tube Microbioreactors for Cell and Tissue Manufacturing

The production of mammalian cells in large quantities is essential for various applications. However, scaling up cell culture using existing bioreactors poses significant technical challenges and high costs. To address this, we previously developed an innovative 3D culture system, known as the AlgTube cell culture system, for high-density cell cultivation. This system involves processing cells into microscale alginate hydrogel tubes, which are suspended in the culture medium within a vessel. These hydrogel tubes shield cells from hydrodynamic stress and maintain the cell mass below 400 µm in diameter, facilitating efficient mass transport and creating a favorable microenvironment for cell growth. Under optimized conditions, AlgTubes supported long-term culture with high cell viability, rapid expansion (1000-fold increase over 9 days per passage), and high yield (5×10⁸ cells/mL), offering significant advantages over conventional methods. Despite these benefits, AlgTubes have critical drawbacks. They are mechanically fragile, with frequent breakage during culture leading to cell leakage and production failures. Additionally, many cell types exhibit poor growth due to the inability to adhere to the alginate surface, making alginate hydrogel microtubes unsuitable for industrial-scale cell production. To overcome these challenges, we developed a novel collagen hydrogel tube-based microbioreactor system in this work. This system provides enhanced robustness and adhesion, enabling scalable, cost-effective, and efficient cell production for a wide range of applications.

Cell therapies for viral diseases: a new frontier

Despite advances in medicine and antimicrobial research, viral infections continue to pose a major threat to human health. While major strides have been made in generating vaccines and small molecules to combat emerging pathogens, new modalities of treatment are warranted in diseases where there is a lack of treatment options, or where treatment cannot fully eradicate pathogens, as in HIV infection. Cellular therapies, some of which are FDA approved for treating cancer, take advantage of our developing understanding of the immune system, and harness this knowledge to enhance, or direct, immune responses toward infectious agents. As with cancer, viruses that evade immunity, do so by avoiding immune recognition or by redirecting the cellular responses that would eradicate them. As such, infusing virus specific immune cells has the potential to improve patient outcomes and should be investigated as a potential tool in the arsenal to fight infection. The present manuscript summarizes key findings made using cellular therapies for the treatment of viral infections, focusing on the potential that these strategies might have in controlling disease.

Activated neutrophils: A next generation cellular immunotherapy

Cell therapies are at the forefront of novel therapeutics. Neutrophils, despite being the most populous immune cells in human blood circulation, are not considered a viable option for cellular therapies because of their short lifespan and poor understanding of their role in the pathophysiology of various diseases. In inflammatory conditions, neutrophils exhibit an activated phenotype. Activation brings about significant changes to neutrophil biology such as increased lifespan, inflammatory cytokine secretion, and enhanced effector functions. Activated neutrophils also possess the potential to stimulate the downstream immune response and are described as essential effectors in the immune response to tumors. This makes activated neutrophils an interesting candidate for cell therapies. Here, we review the biology of activated neutrophils in detail. We discuss the different ways neutrophils can be activated and the effect they have on other immune cells for stimulation of downstream immune response. We review the conditions where activated neutrophil therapy can be therapeutically beneficial and discuss the challenges associated with their eventual translation. Overall, this review summarizes the current state of understanding of neutrophil-based immunotherapies and their clinical potential.

Heterogeneity of tumor-associated neutrophils in hepatocellular carcinoma

Neutrophils are the most abundant cell type in human blood and play a crucial role in the immune system and development of tumors. This review begins with the generation and development of neutrophils, traces their release from the bone marrow into the bloodstream, and finally discusses their role in the hepatocellular carcinoma (HCC) microenvironment. It elaborates in detail the mechanisms by which tumor-associated neutrophils (TANs) exert antitumor or protumor effects under the influence of various mediators in the tumor microenvironment. Neutrophils can exert antitumor effects through direct cytotoxic action. However, they can also accelerate the formation and progression of HCC by being recruited and infiltrated, promoting tumor angiogenesis, and maintaining an immunosuppressive microenvironment. Therefore, based on the heterogeneity and plasticity of neutrophils in tumor development, this review summarizes the current immunotherapies targeting TANs, discusses potential opportunities and challenges, and provides new insights into exploring more promising strategies for treating HCC.

Effect of neutrophils on tumor immunity and immunotherapy resistance with underlying mechanisms

Neutrophils are key mediators of the immune response and play essential roles in the development of tumors and immune evasion. Emerging studies indicate that neutrophils also play a critical role in the immunotherapy resistance in cancer. In this review, firstly, we summarize the novel classification and phenotypes of neutrophils and describe the regulatory relationships between neutrophils and tumor metabolism, flora microecology, neuroendocrine and tumor therapy from a new perspective. Secondly, we review the mechanisms by which neutrophils affect drug resistance in tumor immunotherapy from the aspects of the immune microenvironment, tumor antigens, and epigenetics. Finally, we propose several promising strategies for overcoming tumor immunotherapy resistance by targeting neutrophils and provide new research ideas in this area.

Nanocarriers in glioblastoma treatment: a neuroimmunological perspective

Glioblastoma multiforme (GBM) is the most fatal brain tumor with a poor prognosis with current treatments, mainly because of intrinsic resistance processes. GBM is also referred to as grade 4 astrocytoma, that makes up about 15.4 % of brain cancers globally as well as 60-75 % of astrocytoma. The most prevalent therapeutic choices for GBM comprise surgery in combination with radiotherapy and chemotherapy, providing patients with an average survival of 6-14 months. Nanocarriers provide various benefits such as enhanced drug solubility, biocompatibility, targeted activity, as well as minimized side effects. In addition, GBM treatment comes with several challenges such as the presence of the blood-brain barrier (BBB), blood-brain tumor barrier (BBTB), overexpressed efflux pumps, infiltration, invasion, drug resistance, as well as immune escape due to tumor microenvironment (TME) and cancer stem cells (CSC). Recent research has focused on nanocarriers due to their ability to self-assemble, improve bioavailability, provide controlled release, and penetrate the BBB. These nano-based components could potentially enhance drug accumulation in brain tumor tissues and reduce systemic toxicity, making them a compelling solution for GBM therapy. This review captures the complexities associated with multi-functional nano drug delivery systems (NDDS) in crossing the blood-brain barrier (BBB) and targeting cancer cells. In addition, it presents a succinct overview of various types of targeted multi-functional nano drug delivery system (NDDS) which has exhibited promising value for improving drug delivery to the brain.

Neutrophil and Colorectal Cancer

Colorectal cancer (CRC) is often associated with metastasis and recurrence and is the leading cause of cancer-related mortality. In the progression of CRC, recent studies have highlighted the critical role of neutrophils, particularly tumor-associated neutrophils (TANs). TANs have both tumor-promoting and tumor-suppressing activities, contributing to metastasis, immunosuppression, angiogenesis, and epithelial-to-mesenchymal transition. Tumor-promoting TANs promote tumor growth by releasing proteases, reactive oxygen species, and cytokines, whereas tumor-suppressing TANs enhance immune responses by activating T cells and natural killer cells. Understanding the mechanisms underlying TAN mobilization, plasticity, and their role in the tumor microenvironment has revealed potential therapeutic targets. This review provides a comprehensive overview of TAN biology in CRC and discusses both the tumor-promoting and tumor-suppressing functions of neutrophils. Novel therapeutic approaches targeting TANs, such as chemokine receptor antagonists, aim to modulate neutrophil reprogramming and offer promising avenues for improving treatment outcomes of CRC.

Targeting Cancer: Microenvironment and Immunotherapy Innovations

In 2024, the United States was projected to experience 2 million new cancer diagnoses and approximately 611,720 cancer-related deaths, reflecting a broader global trend in which cancer cases are anticipated to exceed 35 million by 2050. This increasing burden highlights ongoing challenges in cancer treatment despite significant advances that have reduced cancer mortality by 31% since 1991. Key obstacles include the disease's inherent heterogeneity and complexity, such as treatment resistance, cancer stem cells, and the multifaceted tumor microenvironment (TME). The TME-comprising various tumor and immune cells, blood vessels, and biochemical factors-plays a crucial role in tumor growth and resistance to therapies. Recent innovations in cancer treatment, particularly in the field of immuno-oncology, have leveraged insights into TME interactions. An emerging example is the FDA-approved therapy using tumor-infiltrating lymphocytes (TILs), demonstrating the potential of cell-based approaches in solid tumors. However, TIL therapy is just one of many strategies being explored. This review provides a comprehensive overview of the emerging field of immuno-oncology, focusing on how novel therapies targeting or harnessing components of the TME could enhance treatment efficacy and address persistent challenges in cancer care.

CRISPR-Cas9-mediated homology-directed repair for precise gene editing

CRISPR-Cas9-mediated homology-directed repair (HDR) is a versatile platform for creating precise site-specific DNA insertions, deletions, and substitutions. These precise edits are made possible through the use of exogenous donor templates that carry the desired sequence. CRISPR-Cas9-mediated HDR can be widely used to study protein functions, disease modeling, and gene therapy. However, HDR is limited by its low efficiency, especially in postmitotic cells. Here, we review CRISPR-Cas9-mediated HDR, with a focus on methodologies for boosting HDR efficiency, and applications of precise editing via HDR. First, we describe two common mechanisms of DNA repair, non-homologous end joining (NHEJ), and HDR, and discuss their impact on CRISPR-Cas9-mediated precise genome editing. Second, we discuss approaches for improving HDR efficiency through inhibition of the NHEJ pathway, activation of the HDR pathway, modification of donor templates, and delivery of Cas9/sgRNA reagents. Third, we summarize the applications of HDR for protein labeling in functional studies, disease modeling, and ex vivo and in vivo gene therapies. Finally, we discuss alternative precise editing platforms and their limitations, and describe potential avenues to improving CRISPR-Cas9-mediated HDR efficiency and fidelity in future research.

The development and application of chimeric antigen receptor natural killer (CAR-NK) cells for cancer therapy: current state, challenges and emerging therapeutic advances

Immunotherapy has transformed the landscape of cancer treatment, with chimeric antigen receptor (CAR)-engineered T (CAR-T) cell therapy emerging as a front runner in addressing some hematological malignancies. Despite its considerable efficacy, the occurrence of severe adverse effects associated with CAR-T cell therapy has limited their scope and prompted the exploration of alternative therapeutic strategies. Natural killer (NK) cells, characterized by both their innate cytotoxicity and ability to lyse target cells without the constraint of peptide specificity conferred by a major histocompatibility complex (MHC), have similarly garnered attention as a viable immunotherapy. As such, another therapeutic approach has recently emerged that seeks to combine the continued success of CAR-T cell therapy with the flexibility of NK cells. Clinical trials involving CAR-engineered NK (CAR-NK) cell therapy have exhibited promising efficacy with fewer deleterious side effects. This review aims to provide a concise overview of the cellular and molecular basis of NK cell biology, facilitating a better understanding of advancements in CAR design and manufacturing. The focus is on current approaches and strategies employed in CAR-NK cell development, exploring at both preclinical and clinical settings. We will reflect upon the achievements, advantages, and challenges intrinsic to CAR-NK cell therapy. Anticipating the maturation of CAR-NK cell therapy technology, we foresee its encouraging prospects for a broader range of cancer patients and other conditions. It is our belief that this CAR-NK progress will bring us closer to making significant strides in the treatment of refractory and recurrent cancers, as well as other immune-mediated disorders.

Cerebral biomimetic nano-drug delivery systems: A frontier strategy for immunotherapy

Brain diseases are a significant threat to human health, especially in the elderly, and this problem is growing as the aging population increases. Efficient brain-targeted drug delivery has been the greatest challenge in treating brain disorders due to the unique immune environment of the brain, including the blood-brain barrier (BBB). Recently, cerebral biomimetic nano-drug delivery systems (CBNDSs) have provided a promising strategy for brain targeting by mimicking natural biological materials. Herein, this review explores the latest understanding of the immune microenvironment of the brain, emphasizing the immune mechanisms of the occurrence and progression of brain disease. Several brain targeting systems are summarized, including cell-based, exosome-based, protein-based, and microbe-based CBNDSs, and their immunological mechanisms are highlighted. Moreover, given the rise of immunotherapy, the latest applications of CBNDSs in immunotherapy are also discussed. This review provides a comprehensive understanding of CBNDSs and serves as a guideline for immunotherapy in treating brain diseases. In addition, it provides inspiration for the future of CBNDSs.

Glutathione-Depleted Photodynamic Nanoadjuvant for Triggering Nonferrous Ferroptosis to Amplify Radiotherapy of Breast Cancer

Radiotherapy plays a crucial role in the treatment of advanced breast cancer, but the increased antioxidant system, especially the rise in glutathione (GSH), presents a significant obstacle to its effectiveness. To address this challenge, a versatile GSH-depleted photodynamic nanoadjuvant is developed to augment the efficacy of radiotherapy for breast cancer treatment. This nanoadjuvant operates within the tumor microenvironment to effectively deplete intracellular GSH through a sequence of cascaded processes, including GSH exhaustion, biosynthetic inhibition, and photodynamic oxidation. This leads to a notable accumulation of lipid peroxides (LPO) and subsequent suppression of glutathione peroxidase 4 (GPX4) activity. Consequently, the combined GSH depletion induced by the nanoadjuvant markedly promotes nonferrous ferroptosis, thereby contributing to the augmentation of antitumor efficiency during radiotherapy in breast cancer. This work presents an innovative approach to designing and synthesizing biocompatible nanoadjuvants with the goal of improving the efficacy of radiotherapy for breast cancer in prospective clinical scenarios.

Advancements in adoptive CAR immune cell immunotherapy synergistically combined with multimodal approaches for tumor treatment

Adoptive immunotherapy, notably involving chimeric antigen receptor (CAR)-T cells, has obtained Food and Drug Administration (FDA) approval as a treatment for various hematological malignancies, demonstrating promising preclinical efficacy against cancers. However, the intricate and resource-intensive autologous cell processing, encompassing collection, expansion, engineering, isolation, and administration, hamper the efficacy of this therapeutic modality. Furthermore, conventional CAR T therapy is presently confined to addressing solid tumors due to impediments posed by physical barriers, the potential for cytokine release syndrome, and cellular exhaustion induced by the immunosuppressive and heterogeneous tumor microenvironment. Consequently, a strategic integration of adoptive immunotherapy with synergistic multimodal treatments, such as chemotherapy, radiotherapy, and vaccine therapy etc., emerges as a pivotal approach to surmount these inherent challenges. This collaborative strategy holds the key to addressing the limitations delineated above, thereby facilitating the realization of more precise personalized therapies characterized by heightened therapeutic efficacy. Such synergistic strategy not only serves to mitigate the constraints associated with adoptive immunotherapy but also fosters enhanced clinical applicability, thereby advancing the frontiers of therapeutic precision and effectiveness.

Novel immunotherapeutic approaches in gastric cancer

Gastric cancer is a malignant tumor that ranks third in cancer-related deaths worldwide. Early-stage gastric cancer can often be effectively managed through surgical resection. However, the majority of cases are diagnosed in advanced stages, where outcomes with conventional radiotherapy and chemotherapy remain unsatisfactory. Immunotherapy offers a novel approach to treating molecularly heterogeneous gastric cancer by modifying the immunosuppressive tumor microenvironment. Immune checkpoint inhibitors and adoptive cell therapy are regarded as promising modalities in cancer immunotherapy. Food and Drug Administration-approved programmed death-receptor inhibitors, such as pembrolizumab, in combination with chemotherapy, have significantly extended overall survival in gastric cancer patients and is recommended as a first-line treatment. Despite challenges in solid tumor applications, adoptive cell therapy has demonstrated efficacy against various targets in gastric cancer treatment. Among these approaches, chimeric antigen receptor-T cell therapy research is the most widely explored and chimeric antigen receptor-T cell therapy targeting claudin18.2 has shown acceptable safety and robust anti-tumor capabilities. However, these advancements primarily remain in preclinical stages and further investigation should be made to promote their clinical application. This review summarizes the latest research on immune checkpoint inhibitors and adoptive cell therapy and their limitations, as well as the role of nanoparticles in enhancing immunotherapy.

The Pluripotent Path to Immunotherapy

Adoptive cell therapy (ACT) enhances the patient's own immune cells' ability to identify and eliminate cancer cells. Several immune cell types are currently being applied in autologous ACT, including T cells, natural killer (NK) cells, and macrophages. The cells' inherent antitumor capacity can be used, or they can be targeted toward tumor-associated antigen through expression of a chimeric antigen receptor (CAR). Although CAR-based ACT has achieved great results in hematologic malignancies, the accessibility of ACT is limited by the autologous nature of the therapy. Induced pluripotent stem cells (iPSCs) hold the potential to address this challenge, because they can provide an unlimited source for the in vitro generation of immune cells. Various immune subsets have been generated from iPSC for application in ACT, including several T-cell subsets (αβT cells, mucosal-associated invariant T cells, invariant NKT [iNKT] cells, and γδT cells), as well as NK cells, macrophages, and neutrophils. iPSC-derived αβT, NK, and iNKT cells are currently being tested in phase I clinical trials. The ability to perform (multiplexed) gene editing at the iPSC level and subsequent differentiation into effector populations not only expands the arsenal of ACT but allows for development of ACT utilizing cell types which cannot be efficiently obtained from peripheral blood or engineered and expanded in vitro.

Multifaceted roles of neutrophils in tumor microenvironment

Neutrophils, the most abundant leukocyte population in circulation, play a crucial role in detecting and responding to foreign cells, such as pathogens and tumor cells. However, the impact of neutrophils on cancer pathogenesis has been overlooked because of their short lifespan, terminal differentiation, and limited transcriptional activity. Within the tumor microenvironment (TME), neutrophils can be influenced by tumor cells or other stromal cells to acquire either protumor or antitumor properties via the cytokine environment. Despite progress in neutrophil-related research, a comprehensive understanding of tissue-specific neutrophil diversity and adaptability in the TME is still lacking, which poses a significant obstacle to the development of neutrophil-based cancer therapies. This review evaluated the current studies on the dual roles of neutrophils in cancer progression, emphasizing their importance in predicting clinical outcomes, and explored various approaches for targeting neutrophils in cancer treatment, including their potential synergy with cancer immunotherapy.

ROS-responsive glycol chitosan-linked prodrug nanoparticle as a nanoplatform for tumor chemo-photodynamic therapy

Herein, we designed and synthesized novel reactive oxygen species (ROS)-responsive glycol chitosan-doxorubicin (DOX) prodrug via a ROS-cleavable thioketal (TK) linker. The obtained GC-TK-DOX formed self-assembled nanoparticles of 312 nm in aqueous media. Photosensitizers zinc phthalocyanine (ZnPc)-loaded GC-TK-DOX (GC-TK-DOX/ZnPc) nanoparticles were fabricated by using a dialysis approach. The GC-TK-DOX and GC-TK-DOX/ZnPc nanoparticles were nearly spherical by transmission electron microscopy (TEM) observation. Under 660-nm laser irradiation, GC-TK-DOX/ZnPc could generate singlet oxygen. Further, GC-TK-DOX/ZnPc nanoparticles exhibited ROS-sensitive release of DOX and ZnPc in vitro. GC-TK-DOX/ZnPc with laser irradiation showed more drug uptake and higher cytotoxic effects than GC-TK-DOX/ZnPc without irradiation, free DOX and GC-TK-DOX in HeLa tumor cells. Overall, these findings suggested that GC-TK-DOX/ZnPc could be a promising nanoarchitecture for synergetic chemo-photodynamic therapy against tumors.

Chimeric antigen receptor adoptive immunotherapy in central nervous system tumors: state of the art on clinical trials, challenges, and emerging strategies to addressing them

PURPOSE OF REVIEW

Central nervous system (CNS) tumors represent a significant unmet medical need due to their enduring burden of high mortality and morbidity. Chimeric antigen receptor (CAR) T-cell therapy emerges as a groundbreaking approach, offering hope for improved treatment outcomes. However, despite its successes in hematological malignancies, its efficacy in solid tumors, including CNS tumors, remains limited. Challenges such as the intricate tumor microenvironment (TME), antigenic heterogeneity, and CAR T-cell exhaustion hinder its effectiveness. This review aims to explore the current landscape of CAR T-cell therapy for CNS tumors, highlighting recent advancements and addressing challenges in achieving therapeutic efficacy.

RECENT FINDINGS

Innovative strategies aim to overcome the barriers posed by the TME and antigen diversity, prevent CAR T-cell exhaustion through engineering approaches and combination therapies with immune checkpoint inhibitors to improving treatment outcomes.

SUMMARY

Researchers have been actively working to address these challenges. Moreover, addressing the unique challenges associated with neurotoxicity in CNS tumors requires specialized management strategies. These may include the development of grading systems, monitoring devices, alternative cell platforms and incorporation of suicide genes. Continued research efforts and clinical advancements are paramount to overcoming the existing challenges and realizing the full potential of CAR T-cell therapy in treating CNS tumors.

New avenues for cancer immunotherapy: Cell-mediated drug delivery systems

Cancer research has become increasingly complex over the past few decades as knowledge of the heterogeneity of cancer cells, their proliferative ability, and their tumor microenvironments has become available. Although conventional therapies remain the most compelling option for cancer treatment to date, immunotherapy is a promising way to harness natural immune defenses to target and kill cancer cells. Cell-mediated drug delivery systems (CDDSs) have been an active line of research for enhancing the therapeutic efficacy and specificity of cancer immunotherapy. These systems can be tailored to different types of immune cells, allowing immune evasion and accumulation in the tumor microenvironment. By enabling the targeted delivery of therapeutic agents such as immune stimulants, cytokines, antibodies, and antigens, CDDSs have improved the survival of some patients with cancer. This review summarizes the research status of CDDSs, with a focus on their underlying mechanisms of action, biology, and clinical applications. We also discuss opportunities and challenges for implementation of CDDSs into mainstream cancer immunotherapy.

Trogocytosis in CAR immune cell therapy: a key mechanism of tumor immune escape

Immune cell therapy based on chimeric antigen receptor (CAR) technology platform has been greatly developed. The types of CAR immune cell therapy have expanded from T cells to innate immune cells such as NK cells and macrophages, and the diseases treated have expanded from hematological malignancies to non-tumor fields such as infectious diseases and autoimmune diseases. Among them, CAR-T and CAR-NK therapy have observed examples of rapid remission in approved clinical trials, but the efficacy is unstable and plagued by tumor resistance. Trogocytosis is a special phenomenon of intercellular molecular transfer that is common in the immune system and is achieved by recipient cells through acquisition and internalization of donor cell-derived molecules and mediates immune effects. Recently, a novel short-term drug resistance mechanism based on trogocytosis has been proposed, and the bidirectional molecular exchange between CAR immune cells and tumor cells triggered by trogocytosis partially explains the long-term relapse phenomenon after treatment with CAR immune cells. In this review, we summarize the research progress of trogocytosis in CAR immunotherapy, discuss the influencing factors of trogocytosis and its direct and indirect interference with CAR immune cells and emphasize that the interference of trogocytosis can further release the potential of CAR immune cell therapy.

Stimuli-Responsive Polymeric Nanocarriers Accelerate On-Demand Drug Release to Combat Glioblastoma

Glioblastoma multiforme (GBM) is a highly malignant brain tumor with a poor prognosis and limited treatment options. Drug delivery by stimuli-responsive nanocarriers holds great promise for improving the treatment modalities of GBM. At the beginning of the review, we highlighted the stimuli-active polymeric nanocarriers carrying therapies that potentially boost anti-GBM responses by employing endogenous (pH, redox, hypoxia, enzyme) or exogenous stimuli (light, ultrasonic, magnetic, temperature, radiation) as triggers for controlled drug release mainly via hydrophobic/hydrophilic transition, degradability, ionizability, etc. Modifying these nanocarriers with target ligands further enhanced their capacity to traverse the blood-brain barrier (BBB) and preferentially accumulate in glioma cells. These unique features potentially lead to more effective brain cancer treatment with minimal adverse reactions and superior therapeutic outcomes. Finally, the review summarizes the existing difficulties and future prospects in stimuli-responsive nanocarriers for treating GBM. Overall, this review offers theoretical guidelines for developing intelligent and versatile stimuli-responsive nanocarriers to facilitate precise drug delivery and treatment of GBM in clinical settings.

Biomimetic nanocarriers in cancer therapy: based on intercellular and cell-tumor microenvironment communication

Inspired by the concept of "natural camouflage," biomimetic drug delivery systems have emerged to address the limitations of traditional synthetic nanocarriers, such as poor targeting, susceptibility to identification and clearance, inadequate biocompatibility, low permeability, and systemic toxicity. Biomimetic nanocarriers retain the proteins, nucleic acids, and other components of the parent cells. They not only facilitate drug delivery but also serve as communication media to inhibit tumor cells. This paper delves into the communication mechanisms between various cell-derived biomimetic nanocarriers, tumor cells, and the tumor microenvironment, as well as their applications in drug delivery. In addition, the additional communication capabilities conferred on the modified biomimetic nanocarriers, such as targeting and environmental responsiveness, are outlined. Finally, we propose future development directions for biomimetic nanocarriers, hoping to inspire researchers in their design efforts and ultimately achieve clinical translation.

Potential alternatives to αβ-T cells to prevent graft-versus-host disease (GvHD) in allogeneic chimeric antigen receptor (CAR)-based cancer immunotherapy: A comprehensive review

Currently, CAR-T cell therapy relies on an individualized manufacturing process in which patient's own T cells are infused back into patients after being engineered and expanded ex vivo. Despite the astonishing outcomes of autologous CAR-T cell therapy, this approach is endowed with several limitations and drawbacks, such as high cost and time-consuming manufacturing process. Switching the armature of CAR-T cell therapy from autologous settings to allogeneic can overcome several bottlenecks of the current approach. Nevertheless, the use of allogeneic CAR-T cells is limited by the risk of life-threatening GvHD. Thus, in recent years, developing a method to move CAR-T cell therapy to allogeneic settings without the risk of GvHD has become a hot research topic in this field. Since the alloreactivity of αβ T-cell receptor (TCR) accounts for developing GvHD, several efforts have been made to disrupt endogenous TCR of allogeneic CAR-T cells using gene editing tools to prevent GvHD. Nonetheless, the off-target activity of gene editing tools and their associated genotoxicities, as well as the negative consequences of endogenous TCR disruption, are the main concerns of using this approach. As an alternative, CAR αβ-T cells can be replaced with other types of CAR-engineered cells that are capable of recognizing and killing malignant cells through CAR while avoiding the induction of GvHD. These alternatives include T cell subsets with restricted TCR repertoire (γδ-T, iNKT, virus-specific T, double negative T cells, and MAIT cells), killer cells (NK and CIK cells), non-lymphocytic cells (neutrophils and macrophages), stem/progenitor cells, and cell-free extracellular vesicles. In this review, we discuss how these alternatives can move CAR-based immunotherapy to allogeneic settings to overcome the bottlenecks of autologous manner without the risk of GvHD. We comprehensively discuss the pros and cons of these alternatives over the traditional CAR αβ-T cells in light of their preclinical studies and clinical trials.

Blood-Brain Barrier Conquest in Glioblastoma Nanomedicine: Strategies, Clinical Advances, and Emerging Challenges

Glioblastoma (GBM) is a prevalent type of malignancy within the central nervous system (CNS) that is associated with a poor prognosis. The standard treatment for GBM includes the surgical resection of the tumor, followed by radiotherapy and chemotherapy; yet, despite these interventions, overall treatment outcomes remain suboptimal. The blood-brain barrier (BBB), which plays a crucial role in maintaining the stability of brain tissue under normal physiological conditions of the CNS, also poses a significant obstacle to the effective delivery of therapeutic agents to GBMs. Recent preclinical studies have demonstrated that nanomedicine delivery systems (NDDSs) offer promising results, demonstrating both effective GBM targeting and safety, thereby presenting a potential solution for targeted drug delivery. In this review, we first explore the various strategies employed in preclinical studies to overcome the BBB for drug delivery. Subsequently, the results of the clinical translation of NDDSs are summarized, highlighting the progress made. Finally, we discuss potential strategies for advancing the development of NDDSs and accelerating their translational research through well-designed clinical trials in GBM therapy.

Innate immune cells in tumor microenvironment: A new frontier in cancer immunotherapy

Innate immune cells, crucial in resisting infections and initiating adaptive immunity, play diverse and significant roles in tumor development. These cells, including macrophages, granulocytes, dendritic cells (DCs), innate lymphoid cells, and innate-like T cells, are pivotal in the tumor microenvironment (TME). Innate immune cells are crucial components of the TME, based on which various immunotherapy strategies have been explored. Immunotherapy strategies, such as novel immune checkpoint inhibitors, STING/CD40 agonists, macrophage-based surface backpack anchoring, ex vivo polarization approaches, DC-based tumor vaccines, and CAR-engineered innate immune cells, aim to enhance their anti-tumor potential and counteract cancer-induced immunosuppression. The proximity of innate immune cells to tumor cells in the TME also makes them excellent drug carriers. In this review, we will first provide a systematic overview of innate immune cells within the TME and then discuss innate cell-based therapeutic strategies. Furthermore, the research obstacles and perspectives within the field will also be addressed.

Microenvironmental regulation of tumor-associated neutrophils in malignant glioma: from mechanism to therapy

Glioma is the most common primary intracranial tumor in adults, with high incidence, recurrence, and mortality rates. Tumor-associated neutrophils (TANs) are essential components of the tumor microenvironment (TME) in glioma and play a crucial role in glioma cell proliferation, invasion and proneural-mesenchymal transition. Besides the interactions between TANs and tumor cells, the multi-dimensional crosstalk between TANs and other components within TME have been reported to participate in glioma progression. More importantly, several therapies targeting TANs have been developed and relevant preclinical and clinical studies have been conducted in cancer therapy. In this review, we introduce the origin of TANs and the functions of TANs in malignant behaviors of glioma, highlighting the microenvironmental regulation of TANs. Moreover, we focus on summarizing the TANs-targeted methods in cancer therapy, aiming to provide insights into the mechanisms and therapeutic opportunities of TANs in the malignant glioma microenvironment.

Intratumoral Microbiota as a Target for Advanced Cancer Therapeutics

In recent years, advancements in microbial sequencing technology have sparked an increasing interest in the bacteria residing within solid tumors and its distribution and functions in various tumors. Intratumoral bacteria critically modulate tumor oncogenesis and development through DNA damage induction, chronic inflammation, epigenetic alterations, and metabolic and immune regulation, while also influencing cancer treatment efficacy by affecting drug metabolism. In response to these discoveries, a variety of anti-cancer therapies targeting these microorganisms have emerged. These approaches encompass oncolytic therapy utilizing tumor-associated bacteria, the design of biomaterials based on intratumoral bacteria, the use of intratumoral bacterial components for drug delivery systems, and comprehensive strategies aimed at the eradication of tumor-promoting bacteria. Herein, this review article summarizes the distribution patterns of bacteria in different solid tumors, examines their impact on tumors, and evaluates current therapeutic strategies centered on tumor-associated bacteria. Furthermore, the challenges and prospects for developing drugs that target these bacterial communities are also explored, promising new directions for cancer treatment.