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

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.

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.

Potential applications of macrophages in cancer immunotherapy

Immunotherapy has improved cancer treatment based on investigations of tumor immune escape. Manipulation of the immune system stimulates antitumor immune responses and blocks tumor immune escape routes. Genetically adoptive cell therapy, such as T cells, has yielded promising results for hematologic malignancies, but their application to solid tumors has been challenging. Macrophages have a wide broad of capabilities in regulating immune responses, homeostasis, and tissue development, as well as the ability to phagocyte, present antigens, and infiltrate the tumor microenvironment (TME). Given the importance of macrophages in cancer development, they could serve as novel tool for tumor treatment. Therefore, macrophages are used in different formats for direct and indirect targeting of tumor cells. This review summarized the available data on the various applications of macrophages in cancer immunotherapy.

Classical Monocytes Shuttling for Precise Delivery of Nanotherapeutics to Glioblastoma

Glioblastoma (GBM) is the most aggressive brain tumor for which current therapies have limited efficacy. Immunosuppression and difficulties in accessing tumors with therapeutic agents are major obstacles for GBM treatments. Classical monocytes (CMs) possess the strongest infiltration among myeloid cells recruited into tumors during tumorigenesis. In this study, CMs are utilized to deliver the small-molecule CUDC-907 encapsulated in nanoparticles (907-NPs@CMs) for GBM therapy. Hitchhiking on CMs enables more 907-NPs to successfully penetrate the blood-brain barrier (BBB) and reach the interior of tumors. Results demonstrate that 907-NPs@CMs significantly improve the survival rates by suppressing tumor growth and reversing the immunosuppression of tumor microenvironment (TME). Furthermore, the high delivery efficiency of CMs reduces the amount of CUDC-907 required for treatments, reducing the physiological toxicity and off-target effects caused by high doses. 907-NPs@CMs is a safe and versatile therapeutic system that provides a platform for targeted drug delivery to tumors and the ability to treat GBM through a combination of chemotherapy and immunotherapy.

Advances in manufacturing chimeric antigen receptor immune cell therapies

Biomedical research has witnessed significant strides in manufacturing chimeric antigen receptor T cell (CAR-T) therapies, marking a transformative era in cellular immunotherapy. Nevertheless, existing manufacturing methods for autologous cell therapies still pose several challenges related to cost, immune cell source, safety risks, and scalability. These challenges have motivated recent efforts to optimize process development and manufacturing for cell therapies using automated closed-system bioreactors and models created using artificial intelligence. Simultaneously, non-viral gene transfer methods like mRNA, CRISPR genome editing, and transposons are being applied to engineer T cells and other immune cells like macrophages and natural killer cells. Alternative sources of primary immune cells and stem cells are being developed to generate universal, allogeneic therapies, signaling a shift away from the current autologous paradigm. These multifaceted innovations in manufacturing underscore a collective effort to propel this therapeutic approach toward broader clinical adoption and improved patient outcomes in the evolving landscape of cancer treatment. Here, we review current CAR immune cell manufacturing strategies and highlight recent advancements in cell therapy scale-up, automation, process development, and engineering.

Targeted Delivery of Nanoparticle-Conveyed Neutrophils to the Glioblastoma Site for Efficient Therapy

Glioblastoma is a common brain tumor that poses considerable challenges in drug delivery. In this study, we investigated the potential of cell-based nanoparticles for targeted drug delivery to the glioblastoma sites. The anticancer drug of temozolomide (TMZ)-loaded T7-cholesterol nanoparticle micelles efficiently delivered nanoparticles to neutrophils and, subsequently, to the tumors. T7 is a cell-penetrating peptide that enhances the delivery of T7/TMZ to the target cells. T7 also serves as a transferrin target peptide, enabling targeted delivery to tumors. T7-conjugated cholesterol can self-assemble into micelles in aqueous solution and attach to the membrane of neutrophils. We confirmed that T7/TMZ nanoparticle micelles were efficiently located inside the neutrophils. Thereafter, T7/TMZ-conveyed neutrophils were administered to a glioblastoma mouse model, enabling neutrophils to penetrate the blood-brain barrier and deliver drugs directly to the tumor site. We evaluated the drug delivery efficiency and therapeutic effects of intravenous injection of T7/TMZ-conveyed neutrophils to a glioblastoma mouse model. These results demonstrate the promising role of neutrophil-based nanoparticle delivery systems in the targeted therapy of glioblastoma.

Neutrophil generation from hematopoietic progenitor cells and induced pluripotent stem cells (iPSCs): potential applications

Neutrophils are the most frequent immune cell type in peripheral blood, performing an essential role against pathogens. People with neutrophil deficiencies are susceptible to deadly infections, highlighting the importance of generating these cells in host immunity. Neutrophils can be generated from hematopoietic progenitor cells (HPCs) and embryonic stem cells (ESCs) using a cocktail of cytokines. In addition, induced pluripotent stem cells (iPSCs) can be differentiated into various functional cell types, including neutrophils. iPSCs can be derived from differentiated cells, such as skin and blood cells, by reprogramming them to a pluripotent state. Neutrophil generation from iPSCs involves a multistep process that can be performed through feeder cell-dependent and feeder cell-independent manners. Various cytokines and growth factors, in particular, stem cell facto, IL-3, thrombopoietin and granulocyte colony-stimulating factor (G-CSF), are used in both methods, especially, G-CSF which induces the final differentiation of neutrophils in the granulocyte lineage. iPSC-derived neutrophils have been used as a valuable tool for studying rare genetic disorders affecting neutrophils. The iPSC-derived neutrophils can also be used for disease modeling, infection research and drug discovery. However, several challenges must be overcome before iPSC-derived neutrophils can be used therapeutically in transplantation medicine. This review provides an overview of the commonly employed protocols for generating neutrophils from HPCs, ESCs and iPSCs and discusses the potential applications of the generated cells in research and medicine.

Beyond CAR T cells: exploring alternative cell sources for CAR-like cellular therapies

Chimeric antigen receptor (CAR)-T cell therapy has led to remarkable clinical outcomes in the treatment of hematological malignancies. However, challenges remain, such as limited infiltration into solid tumors, inadequate persistence, systemic toxicities, and manufacturing insufficiencies. The use of alternative cell sources for CAR-based therapies, such as natural killer cells (NK), macrophages (MΦ), invariant Natural Killer T (iNKT) cells, γδT cells, neutrophils, and induced pluripotent stem cells (iPSC), has emerged as a promising avenue. By harnessing these cells' inherent cytotoxic mechanisms and incorporating CAR technology, common CAR-T cell-related limitations can be effectively mitigated. We herein present an overview of the tumoricidal mechanisms, CAR designs, and manufacturing processes of CAR-NK cells, CAR-MΦ, CAR-iNKT cells, CAR-γδT cells, CAR-neutrophils, and iPSC-derived CAR-cells, outlining the advantages, limitations, and potential solutions of these therapeutic strategies.

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.

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.

Tumour-associated neutrophils: Potential therapeutic targets in pancreatic cancer immunotherapy

Pancreatic cancer (PC) is a highly malignant tumour of the digestive system with poor therapeutic response and low survival rates. Immunotherapy has rapidly developed in recent years and has achieved significant outcomes in numerous malignant neoplasms. However, responses to immunotherapy in PC are rare, and the immunosuppressive and desmoplastic tumour microenvironment (TME) significantly hinders their efficacy in PC. Tumour-associated neutrophils (TANs) play a crucial role in the PC microenvironment and exert a profound influence on PC immunotherapy by establishing a robust stromal shelter and restraining immune cells to assist PC cells in immune escape, which may subvert the current status of PC immunotherapy. The present review aims to offer a comprehensive summary of the latest progress in understanding the involvement of TANs in PC desmoplastic and immunosuppressive functions and to emphasise the potential therapeutic implications of focusing on TANs in the immunotherapy of this deleterious disease. Finally, we provide an outlook for the future use of TANs in PC immunotherapy.

PTP1B phosphatase dampens iPSC-derived neutrophil motility and antimicrobial function

Neutrophils are rapidly recruited to sites of infection and are critical for pathogen clearance. Therapeutic use of primary neutrophils has been limited, as they have a short lifespan and are not amenable to genetic manipulation. Human induced pluripotent stem cells (iPSCs) can provide a robust source of neutrophils for infusion and are genetically tractable. However, current work has indicated that dampened intracellular signaling limits iPSC-derived neutrophil (iNeutrophil) cellular activation and antimicrobial response. Here, we show that protein tyrosine phosphatase 1B (PTP1B) inhibits intracellular signaling and dampens iNeutrophil effector function. Deletion of the PTP1B phosphatase increased PI3K and ERK signaling and was associated with increased F-actin polymerization, cell migration, and phagocytosis. In contrast, other effector functions like NETosis and reactive oxygen species production were reduced. PTP1B-deficient neutrophils were more responsive to Aspergillus fumigatus and displayed rapid recruitment and control of hyphal growth. Accordingly, depletion of PTP1B increased production of inflammatory factors including the neutrophil chemokine interleukin-8. Taken together, these findings suggest that PTP1B limits iNeutrophil motility and antimicrobial function.

Contemporary Approaches to Immunotherapy of Solid Tumors

In recent years, the arrival of the immunotherapy industry has introduced the possibility of providing transformative, durable, and potentially curative outcomes for various forms of malignancies. However, further research has shown that there are a number of issues that significantly reduce the effectiveness of immunotherapy, especially in solid tumors. First of all, these problems are related to the protective mechanisms of the tumor and its microenvironment. Currently, major efforts are focused on overcoming protective mechanisms by using different adoptive cell therapy variants and modifications of genetically engineered constructs. In addition, a complex workforce is required to develop and implement these treatments. To overcome these significant challenges, innovative strategies and approaches are necessary to engineer more powerful variations of immunotherapy with improved antitumor activity and decreased toxicity. In this review, we discuss recent innovations in immunotherapy aimed at improving clinical efficacy in solid tumors, as well as strategies to overcome the limitations of various immunotherapies.

Neutrophils, an emerging new therapeutic platform

Neutrophils possess unique characteristics that render them indispensable to health, and patients with irregular neutrophil counts or functions suffer from increased morbidity and mortality. As neutrophils are short-lived postmitotic cells, genetic aberrations cannot be corrected directly in neutrophils and must be targeted in their progenitors. Neutrophils are increasingly being contemplated for a range of therapeutic applications, including restoration or modulation of immune function and targeting of solid tumors. This review addresses the state-of-the-art in neutrophil transfusions and their possible applications for infectious disease prevention and treatment. It offers a landscape of the most recent gene therapy approaches to address neutrophil-related genetic diseases. We also discuss how ongoing research could broaden the applicability of neutrophil-based therapies to solid cancer treatments and beyond.

Nanoparticle-neutrophils interactions for autoimmune regulation

Neutrophils play an essential role as 'first responders' in the immune response, necessitating many immune-modulating capabilities. Chronic, unresolved inflammation is heavily implicated in the progression and tissue-degrading effects of autoimmune disease. Neutrophils modulate disease pathogenesis by interacting with the inflammatory and autoreactive cells through effector functions, including signaling, degranulation, and neutrophil extracellular traps (NETs) release. Since the current gold standard systemic glucocorticoid administration has many drawbacks and side effects, targeting neutrophils in autoimmunity provides a new approach to developing therapeutics. Nanoparticles enable targeting of specific cell types and controlled release of a loaded drug cargo. Thus, leveraging nanoparticle properties and interactions with neutrophils provides an exciting new direction toward novel therapies for autoimmune diseases. Additionally, recent work has utilized neutrophil properties to design novel targeted particles for delivery into previously inaccessible areas. Here, we outline nanoparticle-based strategies to modulate neutrophil activity in autoimmunity, including various nanoparticle formulations and neutrophil-derived targeting.

"On/off"-switchable crosslinked PTX-nanoformulation with improved precise delivery for NSCLC brain metastases and restrained adverse reaction over nab-PTX

Non-small cell lung cancer (NSCLC) brain metastases present a significant treatment challenge due to limited drug delivery efficiency and severe adverse reactions. In this study, we address these challenges by designing a "on/off" switchable crosslinked paclitaxel (PTX) nanocarrier, BPM-PD, with novel ultra-pH-sensitive linkages (pH 6.8 to 6.5). BPM-PD demonstrates a distinct "on/off" switchable release of the anti-cancer drug paclitaxel (PTX) in response to the acidic extratumoral microenvironment. The "off" state of BPM-PD@PTX effectively prevents premature drug release in the blood circulation, blood-brain barrier (BBB)/blood-tumor barrier (BTB), and normal brain tissue, surpassing the clinical PTX-nanoformulation (nab-PTX). Meanwhile, the "on" state facilitates precise delivery to NSCLC brain metastases cells. Compared to nab-PTX, BPM-PD@PTX demonstrates improved therapeutic efficacy with a reduced tumor area (only 14.6%) and extended survival duration, while mitigating adverse reactions (over 83.7%) in aspartate aminotransferase (AST) and alanine aminotransferase (ALT), offering a promising approach for the treatment of NSCLC brain metastases. The precise molecular switch also helped to increase the PTX maximum tolerated dose from 25 mg/kg to 45 mg/kg This research contributes to the field of cancer therapeutics and has significant implications for improving the clinical outcomes of NSCLC patients.

Chimeric antigen receptor-modified macrophages ameliorate liver fibrosis in preclinical models

BACKGROUND & AIMS

Treatments directly targeting fibrosis remain limited. Given the unique intrinsic features of macrophages and their capacity to engraft in the liver, we genetically engineered bone marrow-derived macrophages with a chimeric antigen receptor (CAR) to direct their phagocytic activity against hepatic stellate cells (HSCs) in multiple mouse models. This study aimed to demonstrate the therapeutic efficacy of CAR macrophages (CAR-Ms) in mouse models of fibrosis and cirrhosis and to elucidate the underlying mechanisms.

METHODS

uPAR expression was studied in patients with fibrosis/cirrhosis and in murine models of liver fibrosis, including mice treated with carbon tetrachloride, a 5-diethoxycarbonyl-1, 4-dihydrocollidine diet, or a high-fat/cholesterol/fructose diet. The safety and efficacy of CAR-Ms were evaluated in vitro and in vivo.

RESULTS

Adoptive transfer of CAR-Ms resulted in a significant reduction in liver fibrosis and the restoration of function in murine models of liver fibrosis. CAR-Ms modulated the hepatic immune microenvironment to recruit and modify the activation of endogenous immune cells to drive fibrosis regression. These CAR-Ms were able to recruit and present antigens to T cells and mount specific antifibrotic T-cell responses to reduce fibroblasts and liver fibrosis in mice.

CONCLUSION

Collectively, our findings demonstrate the potential of using macrophages as a platform for CAR technology to provide an effective treatment option for liver fibrosis. CAR-Ms might be developed for treatment of patients with liver fibrosis.

IMPACT AND IMPLICATIONS

Liver fibrosis is an incurable condition that afflicts millions of people globally. Despite the clear clinical need, therapies for liver fibrosis are limited. Our findings provide the first preclinical evidence that chimeric antigen receptor (CAR)-macrophages (CAR-Ms) targeting uPAR can attenuate liver fibrosis and cirrhosis. We show that macrophages expressing this uPAR CAR exert a direct antifibrotic effect and elicit a specific T-cell response that augments the immune response against liver fibrosis. These findings demonstrate the potential of using CAR-Ms as an effective cell-based therapy for the treatment of liver fibrosis.

Synthetic Cells and Molecules in Cellular Immunotherapy

Cellular immunotherapy has emerged as an exciting strategy for cancer treatment, as it aims to enhance the body's immune response to tumor cells by engineering immune cells and designing synthetic molecules from scratch. Because of the cytotoxic nature, abundance in peripheral blood, and maturation of genetic engineering techniques, T cells have become the most commonly engineered immune cells to date. Represented by chimeric antigen receptor (CAR)-T therapy, T cell-based immunotherapy has revolutionized the clinical treatment of hematological malignancies. However, serious side effects and limited efficacy in solid tumors have hindered the clinical application of cellular immunotherapy. To address these limitations, various innovative strategies regarding synthetic cells and molecules have been developed. On one hand, some cytotoxic immune cells other than T cells have been engineered to explore the potential of targeted elimination of tumor cells, while some adjuvant cells have also been engineered to enhance the therapeutic effect. On the other hand, diverse synthetic cellular components and molecules are added to engineered immune cells to regulate their functions, promoting cytotoxic activity and restricting side effects. Moreover, novel bioactive materials such as hydrogels facilitating the delivery of therapeutic immune cells have also been applied to improve the efficacy of cellular immunotherapy. This review summarizes the innovative strategies of synthetic cells and molecules currently available in cellular immunotherapies, discusses the limitations, and provides insights into the next generation of cellular immunotherapies.

Non-Tumor Cells within the Tumor Microenvironment-The "Eminence Grise" of the Glioblastoma Pathogenesis and Potential Targets for Therapy

Glioblastoma (GBM) is the most common malignancy of the central nervous system in adults. GBM has high levels of therapy failure and its prognosis is usually dismal. The phenotypic heterogeneity of the tumor cells, dynamic complexity of non-tumor cell populations within the GBM tumor microenvironment (TME), and their bi-directional cross-talk contribute to the challenges of current therapeutic approaches. Herein, we discuss the etiology of GBM, and describe several major types of non-tumor cells within its TME, their impact on GBM pathogenesis, and molecular mechanisms of such an impact. We also discuss their value as potential therapeutic targets or prognostic biomarkers, with reference to the most recent works on this subject. We conclude that unless all "key player" populations of non-tumor cells within the TME are considered, no breakthrough in developing treatment for GBM can be achieved.

Understanding the immunosuppressive microenvironment of glioma: mechanistic insights and clinical perspectives

Glioblastoma (GBM), the predominant and primary malignant intracranial tumor, poses a formidable challenge due to its immunosuppressive microenvironment, thereby confounding conventional therapeutic interventions. Despite the established treatment regimen comprising surgical intervention, radiotherapy, temozolomide administration, and the exploration of emerging modalities such as immunotherapy and integration of medicine and engineering technology therapy, the efficacy of these approaches remains constrained, resulting in suboptimal prognostic outcomes. In recent years, intensive scrutiny of the inhibitory and immunosuppressive milieu within GBM has underscored the significance of cellular constituents of the GBM microenvironment and their interactions with malignant cells and neurons. Novel immune and targeted therapy strategies have emerged, offering promising avenues for advancing GBM treatment. One pivotal mechanism orchestrating immunosuppression in GBM involves the aggregation of myeloid-derived suppressor cells (MDSCs), glioma-associated macrophage/microglia (GAM), and regulatory T cells (Tregs). Among these, MDSCs, though constituting a minority (4-8%) of CD45+ cells in GBM, play a central component in fostering immune evasion and propelling tumor progression, angiogenesis, invasion, and metastasis. MDSCs deploy intricate immunosuppressive mechanisms that adapt to the dynamic tumor microenvironment (TME). Understanding the interplay between GBM and MDSCs provides a compelling basis for therapeutic interventions. This review seeks to elucidate the immune regulatory mechanisms inherent in the GBM microenvironment, explore existing therapeutic targets, and consolidate recent insights into MDSC induction and their contribution to GBM immunosuppression. Additionally, the review comprehensively surveys ongoing clinical trials and potential treatment strategies, envisioning a future where targeting MDSCs could reshape the immune landscape of GBM. Through the synergistic integration of immunotherapy with other therapeutic modalities, this approach can establish a multidisciplinary, multi-target paradigm, ultimately improving the prognosis and quality of life in patients with GBM.

Convergence of nanomedicine and neutrophils for drug delivery

Neutrophils have recently emerged as promising carriers for drug delivery due to their unique properties including rapid response toward inflammation, chemotaxis, and transmigration. When integrated with nanotechnology that has enormous advantages in improving treatment efficacy and reducing side effects, neutrophil-based nano-drug delivery systems have expanded the repertoire of nanoparticles employed in precise therapeutic interventions by either coating nanoparticles with their membranes, loading nanoparticles inside living cells, or engineering chimeric antigen receptor (CAR)-neutrophils. These neutrophil-inspired therapies have shown superior biocompatibility, targeting ability, and therapeutic robustness. In this review, we summarized the benefits of combining neutrophils and nanotechnologies, the design principles and underlying mechanisms, and various applications in disease treatments. The challenges and prospects for neutrophil-based drug delivery systems were also discussed.

Engineering and Targeting Neutrophils for Cancer Therapy

Neutrophils are the most abundant white blood cells in the circulation and act as the first line of defense against infections. Increasing evidence suggests that neutrophils possess heterogeneous phenotypes and functional plasticity in human health and diseases, including cancer. Neutrophils play multifaceted roles in cancer development and progression, and an N1/N2 paradigm of neutrophils in cancer is proposed, where N1 neutrophils exert anti-tumor properties while N2 neutrophils display tumor-supportive and immune-suppressive functions. Selective activation of beneficial neutrophil population and targeted inhibition or re-polarization of tumor-promoting neutrophils has shown an important potential in tumor therapy. In addition, due to the natural inflammation-responsive and physical barrier-crossing abilities, neutrophils and their derivatives (membranes and extracellular vesicles (EVs)) are regarded as advanced drug delivery carriers for enhanced tumor targeting and improved therapeutic efficacy. In this review, the recent advances in engineering neutrophils for drug delivery and targeting neutrophils for remodeling tumor microenvironment (TME) are comprehensively presented. This review will provide a broad understanding of the potential of neutrophils in cancer therapy.

Biosensor-Enhanced Organ-on-a-Chip Models for Investigating Glioblastoma Tumor Microenvironment Dynamics

Glioblastoma, an aggressive primary brain tumor, poses a significant challenge owing to its dynamic and intricate tumor microenvironment. This review investigates the innovative integration of biosensor-enhanced organ-on-a-chip (OOC) models as a novel strategy for an in-depth exploration of glioblastoma tumor microenvironment dynamics. In recent years, the transformative approach of incorporating biosensors into OOC platforms has enabled real-time monitoring and analysis of cellular behaviors within a controlled microenvironment. Conventional in vitro and in vivo models exhibit inherent limitations in accurately replicating the complex nature of glioblastoma progression. This review addresses the existing research gap by pioneering the integration of biosensor-enhanced OOC models, providing a comprehensive platform for investigating glioblastoma tumor microenvironment dynamics. The applications of this combined approach in studying glioblastoma dynamics are critically scrutinized, emphasizing its potential to bridge the gap between simplistic models and the intricate in vivo conditions. Furthermore, the article discusses the implications of biosensor-enhanced OOC models in elucidating the dynamic features of the tumor microenvironment, encompassing cell migration, proliferation, and interactions. By furnishing real-time insights, these models significantly contribute to unraveling the complex biology of glioblastoma, thereby influencing the development of more accurate diagnostic and therapeutic strategies.

CAR products from novel sources: a new avenue for the breakthrough in cancer immunotherapy

Chimeric antigen receptor (CAR) T cell therapy has transformed cancer immunotherapy. However, significant challenges limit its application beyond B cell-driven malignancies, including limited clinical efficacy, high toxicity, and complex autologous cell product manufacturing. Despite efforts to improve CAR T cell therapy outcomes, there is a growing interest in utilizing alternative immune cells to develop CAR cells. These immune cells offer several advantages, such as major histocompatibility complex (MHC)-independent function, tumor microenvironment (TME) modulation, and increased tissue infiltration capabilities. Currently, CAR products from various T cell subtypes, innate immune cells, hematopoietic progenitor cells, and even exosomes are being explored. These CAR products often show enhanced antitumor efficacy, diminished toxicity, and superior tumor penetration. With these benefits in mind, numerous clinical trials are underway to access the potential of these innovative CAR cells. This review aims to thoroughly examine the advantages, challenges, and existing insights on these new CAR products in cancer treatment.

Neutrophils in cancer: dual roles through intercellular interactions

Neutrophils, the most abundant immune cells in human blood, play crucial and diverse roles in tumor development. In the tumor microenvironment (TME), cancer cells regulate the recruitment and behaviors of neutrophils, transforming some of them into a pro-tumor phenotype. Pro-tumor neutrophils interact with cancer cells in various ways to promote cancer initiation, growth, and metastasis, while anti-tumor neutrophils interact with cancer cells to induce senescence and death. Neutrophils can also interact with other cells in TME, including T cells, macrophages, stromal cells, etc. to exert anti- or pro-tumor functions. In this review, we will analyze the anti- and pro-tumor intercellular interactions mediated by neutrophils, with a focus on generalizing the mechanisms underlying the interaction of neutrophils with tumor cells and T cells. Furthermore, we will provide an overview of cancer treatment strategies targeting neutrophil-mediated cellular interactions.

Targeting neutrophils: Mechanism and advances in cancer therapy

BACKGROUND

Cancer is a thorny problem which cannot be conquered by mankind at present and recent researchers have put their focus on tumor microenviroment. Neutrophils, the prominent leukocytes in peripheral blood that accumulate in tumours, serves as frontline cells in response to tumour progression owing to the rapid development of micro biotechnology. Hence, targeted therapy with these neutrophils has made targeting treatment a promising field in cancer therapy.

MAIN BODY

We broadly summarise some studies on the phenotypes and functions of tumour-associated neutrophils as well as the unique web-like products of neutrophils that play a role in cancer progression-neutrophil extracellular traps-and the interactions between neutrophils and the tumour microenvironment. Moreover, several targeted neutrophils therapeutic studies have made some progress and provided potential strategies for the treatment of cancer.

CONCLUSION

This review aims to offer a holistic perspective on therapeutic interventions targeting neutrophils to further inspire more researches on cancer therapies.

Precise genome-editing in human diseases: mechanisms, strategies and applications

Precise genome-editing platforms are versatile tools for generating specific, site-directed DNA insertions, deletions, and substitutions. The continuous enhancement of these tools has led to a revolution in the life sciences, which promises to deliver novel therapies for genetic disease. Precise genome-editing can be traced back to the 1950s with the discovery of DNA's double-helix and, after 70 years of development, has evolved from crude in vitro applications to a wide range of sophisticated capabilities, including in vivo applications. Nonetheless, precise genome-editing faces constraints such as modest efficiency, delivery challenges, and off-target effects. In this review, we explore precise genome-editing, with a focus on introduction of the landmark events in its history, various platforms, delivery systems, and applications. First, we discuss the landmark events in the history of precise genome-editing. Second, we describe the current state of precise genome-editing strategies and explain how these techniques offer unprecedented precision and versatility for modifying the human genome. Third, we introduce the current delivery systems used to deploy precise genome-editing components through DNA, RNA, and RNPs. Finally, we summarize the current applications of precise genome-editing in labeling endogenous genes, screening genetic variants, molecular recording, generating disease models, and gene therapy, including ex vivo therapy and in vivo therapy, and discuss potential future advances.

Glioblastoma Therapy: Past, Present and Future

Glioblastoma (GB) stands out as the most prevalent and lethal form of brain cancer. Although great efforts have been made by clinicians and researchers, no significant improvement in survival has been achieved since the Stupp protocol became the standard of care (SOC) in 2005. Despite multimodality treatments, recurrence is almost universal with survival rates under 2 years after diagnosis. Here, we discuss the recent progress in our understanding of GB pathophysiology, in particular, the importance of glioma stem cells (GSCs), the tumor microenvironment conditions, and epigenetic mechanisms involved in GB growth, aggressiveness and recurrence. The discussion on therapeutic strategies first covers the SOC treatment and targeted therapies that have been shown to interfere with different signaling pathways (pRB/CDK4/RB1/P16ink4, TP53/MDM2/P14arf, PI3k/Akt-PTEN, RAS/RAF/MEK, PARP) involved in GB tumorigenesis, pathophysiology, and treatment resistance acquisition. Below, we analyze several immunotherapeutic approaches (i.e., checkpoint inhibitors, vaccines, CAR-modified NK or T cells, oncolytic virotherapy) that have been used in an attempt to enhance the immune response against GB, and thereby avoid recidivism or increase survival of GB patients. Finally, we present treatment attempts made using nanotherapies (nanometric structures having active anti-GB agents such as antibodies, chemotherapeutic/anti-angiogenic drugs or sensitizers, radionuclides, and molecules that target GB cellular receptors or open the blood-brain barrier) and non-ionizing energies (laser interstitial thermal therapy, high/low intensity focused ultrasounds, photodynamic/sonodynamic therapies and electroporation). The aim of this review is to discuss the advances and limitations of the current therapies and to present novel approaches that are under development or following clinical trials.

Biomimetic Nano-Drug Delivery System: An Emerging Platform for Promoting Tumor Treatment

With the development of nanotechnology, nanoparticles (NPs) have shown broad prospects as drug delivery vehicles. However, they exhibit certain limitations, including low biocompatibility, poor physiological stability, rapid clearance from the body, and nonspecific targeting, which have hampered their clinical application. Therefore, the development of novel drug delivery systems with improved biocompatibility and high target specificity remains a major challenge. In recent years, biofilm mediated biomimetic nano-drug delivery system (BNDDS) has become a research hotspot focus in the field of life sciences. This new biomimetic platform uses bio-nanotechnology to encapsulate synthetic NPswithin biomimetic membrane, organically integrating the low immunogenicity, low toxicity, high tumor targeting, good biocompatibility of the biofilm with the adjustability and versatility of the nanocarrier, and shows promising applications in the field of precision tumor therapy. In this review, we systematically summarize the new progress in BNDDS used for optimizing drug delivery, providing a theoretical reference for optimizing drug delivery and designing safe and efficient treatment strategies to improve tumor treatment outcomes.

Topical drug delivery strategies for enhancing drug effectiveness by skin barriers, drug delivery systems and individualized dosing

Topical drug delivery is widely used in various diseases because of the advantages of not passing through the gastrointestinal tract, avoiding gastrointestinal irritation and hepatic first-pass effect, and reaching the lesion directly to reduce unnecessary adverse reactions. The skin helps the organism to defend itself against a huge majority of external aggressions and is one of the most important lines of defense of the body. However, the skin's strong barrier ability is also a huge obstacle to the effectiveness of topical medications. Allowing the bioactive, composition in a drug to pass through the stratum corneum barrier as needed to reach the target site is the most essential need for the bioactive, composition to exert its therapeutic effect. The state of the skin barrier, the choice of delivery system for the bioactive, composition, and individualized disease detection and dosing planning influence the effectiveness of topical medications. Nowadays, enhancing transdermal absorption of topically applied drugs is the hottest research area. However, enhancing transdermal absorption of drugs is not the first choice to improve the effectiveness of all drugs. Excessive transdermal absorption enhances topical drug accumulation at non-target sites and the occurrence of adverse reactions. This paper introduces topical drug delivery strategies to improve drug effectiveness from three perspectives: skin barrier, drug delivery system and individualized drug delivery, describes the current status and shortcomings of topical drug research, and provides new directions and ideas for topical drug research.

Protein tyrosine phosphatases as emerging targets for cancer immunotherapy

Contemporary strategies in cancer immunotherapy, despite remarkable success, remain constrained by inherent limitations such as suboptimal patient responses, the emergence of drug resistance, and the manifestation of pronounced adverse effects. Consequently, the need for alternative strategies for immunotherapy becomes clear. Protein tyrosine phosphatases (PTPs) wield a pivotal regulatory influence over an array of essential cellular processes. Substantial research has underscored the potential in targeting PTPs to modulate the immune responses and/or regulate antigen presentation, thereby presenting a novel paradigm for cancer immunotherapy. In this review, we focus on recent advances in genetic and biological validation of several PTPs as emerging targets for immunotherapy. We also highlight recent development of small molecule inhibitors and degraders targeting these PTPs as novel cancer immunotherapeutic agents.

Beyond the horizon: Neutrophils leading the way in the evolution of immunotherapy

Cancer is a complex and dynamic disease, initiated by a multitude of intrinsic mutations and progressed with the assistance of the tissue microenvironment, encompassed by stromal cells including immune cell infiltration. The novel finding that tumors can evade anti-cancer immune functions shaped the field of immunotherapy, which has been a revolutionary approach for the treatment of cancers. However, the development of predominantly T cell-targeted immunotherapy approaches, such as immune checkpoint inhibition, also brought about an accumulation of evidence demonstrating other immune cell drivers of tumor progression, such as innate immune cells and notably, neutrophils. In the past decade, neutrophils have emerged to be primary mediators of multiple cancer types and even in recent years, are gaining attention for their potential use in the next generation of immunotherapies. Here, we review current immunotherapy strategies and thoroughly discuss the roles of neutrophils in cancer and novel neutrophil-targeted methods for treating cancer.

The CAR macrophage cells, a novel generation of chimeric antigen-based approach against solid tumors

Today, adoptive cell therapy has many successes in cancer therapy, and this subject is brilliant in using chimeric antigen receptor T cells. The CAR T cell therapy, with its FDA-approved drugs, could treat several types of hematological malignancies and thus be very attractive for treating solid cancer. Unfortunately, the CAR T cell cannot be very functional in solid cancers due to its unique features. This treatment method has several harmful adverse effects that limit their applications, so novel treatments must use new cells like NK cells, NKT cells, and macrophage cells. Among these cells, the CAR macrophage cells, due to their brilliant innate features, are more attractive for solid tumor therapy and seem to be a better candidate for the prior treatment methods. The CAR macrophage cells have vital roles in the tumor microenvironment and, with their direct effect, can eliminate tumor cells efficiently. In addition, the CAR macrophage cells, due to being a part of the innate immune system, attended the tumor sites. With the high infiltration, their therapy modulations are more effective. This review investigates the last achievements in CAR-macrophage cells and the future of this immunotherapy treatment method.

Advancing CAR-based immunotherapies in solid tumors: CAR- macrophages and neutrophils

Macrophages and neutrophils are the main components of the innate immune system and play important roles in promoting angiogenesis, extracellular matrix remodeling, cancer cell proliferation, and metastasis in the tumor microenvironment (TME). They can also be harnessed to mediate cytotoxic tumor killing effects and orchestrate effective anti-tumor immune responses with proper stimulation and modification. Therefore, macrophages and neutrophils have strong potential in cancer immunotherapy. In this review, we briefly outlined the applications of macrophages or neutrophils in adoptive cell therapies, and focused on chimeric antigen receptor (CAR)-engineered macrophages (CAR-Ms) and neutrophils (CAR-Ns). We summarized the construction strategies, the preclinical and clinical studies of CAR-Ms and CAR-Ns. In the end, we briefly discussed the limitations and challenges of CAR-Ms and CAR-Ns, as well as future research directions to extend their applications in treating solid tumors.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

CNS therapeutics: Immune cells break the barriers

Peripheral immune cells can be seen as attractive vectors and drug carriers for central nervous system therapeutics because these cells have unique properties that allow them to migrate across the blood-brain barrier, enabling drug delivery to brain regions that are inaccessible to free drugs.

Engineered hematopoietic and immune cells derived from human pluripotent stem cells

For the past decade, significant advances have been achieved in human hematopoietic stem cell (HSC) transplantation for treating various blood diseases and cancers. However, challenges remain with the quality control, amount, and cost of HSCs and HSC-derived immune cells. The advent of human pluripotent stem cells (hPSCs) may transform HSC transplantation and cancer immunotherapy by providing a cost-effective and scalable cell source for fundamental studies and translational applications. In this review, we discuss the current developments in the field of stem cell engineering for hematopoietic stem and progenitor cell (HSPC) differentiation and further differentiation of HSPCs into functional immune cells. The key advances in stem cell engineering include the generation of HSPCs from hPSCs, genetic modification of hPSCs, and hPSC-derived HSPCs for improved function, further differentiation of HPSCs into functional immune cells, and applications of cell culture platforms for hematopoietic cell manufacturing. Current challenges impeding the translation of hPSC-HSPCs and immune cells as well as further directions to address these challenges are also discussed.

The local microenvironment drives activation of neutrophils in human brain tumors

Neutrophils are abundant immune cells in the circulation and frequently infiltrate tumors in substantial numbers. However, their precise functions in different cancer types remain incompletely understood, including in the brain microenvironment. We therefore investigated neutrophils in tumor tissue of glioma and brain metastasis patients, with matched peripheral blood, and herein describe the first in-depth analysis of neutrophil phenotypes and functions in these tissues. Orthogonal profiling strategies in humans and mice revealed that brain tumor-associated neutrophils (TANs) differ significantly from blood neutrophils and have a prolonged lifespan and immune-suppressive and pro-angiogenic capacity. TANs exhibit a distinct inflammatory signature, driven by a combination of soluble inflammatory mediators including tumor necrosis factor alpha (TNF-ɑ) and Ceruloplasmin, which is more pronounced in TANs from brain metastasis versus glioma. Myeloid cells, including tumor-associated macrophages, emerge at the core of this network of pro-inflammatory mediators, supporting the concept of a critical myeloid niche regulating overall immune suppression in human brain tumors.

Unravelling the Glioblastoma Tumour Microenvironment: Can Aptamer Targeted Delivery Become Successful in Treating Brain Cancers?

The key challenges to treating glioblastoma multiforme (GBM) are the heterogeneous and complex nature of the GBM tumour microenvironment (TME) and difficulty of drug delivery across the blood-brain barrier (BBB). The TME is composed of various neuronal and immune cells, as well as non-cellular components, including metabolic products, cellular interactions, and chemical compositions, all of which play a critical role in GBM development and therapeutic resistance. In this review, we aim to unravel the complexity of the GBM TME, evaluate current therapeutics targeting this microenvironment, and lastly identify potential targets and therapeutic delivery vehicles for the treatment of GBM. Specifically, we explore the potential of aptamer-targeted delivery as a successful approach to treating brain cancers. Aptamers have emerged as promising therapeutic drug delivery vehicles with the potential to cross the BBB and deliver payloads to GBM and brain metastases. By targeting specific ligands within the TME, aptamers could potentially improve treatment outcomes and overcome the challenges associated with larger therapies such as antibodies.

Nanoparticle-Based Treatment in Glioblastoma

Glioblastoma (GB) is a malignant glioma associated with a mean overall survival of 12 to 18 months, even with optimal treatment, due to its high relapse rate and treatment resistance. The standardized first-line treatment consists of surgery, which allows for diagnosis and cytoreduction, followed by stereotactic fractionated radiotherapy and chemotherapy. Treatment failure can result from the poor passage of drugs through the blood-brain barrier (BBB). The development of novel and more effective therapeutic approaches is paramount to increasing the life expectancy of GB patients. Nanoparticle-based treatments include epitopes that are designed to interact with specialized transport systems, ultimately allowing the crossing of the BBB, increasing therapeutic efficacy, and reducing systemic toxicity and drug degradation. Polymeric nanoparticles have shown promising results in terms of precisely directing drugs to the brain with minimal systemic side effects. Various methods of drug delivery that pass through the BBB, such as the stereotactic injection of nanoparticles, are being actively tested in vitro and in vivo in animal models. A significant variety of pre-clinical studies with polymeric nanoparticles for the treatment of GB are being conducted, with only a few nanoparticle-based drug delivery systems to date having entered clinical trials. Pre-clinical studies are key to testing the safety and efficacy of these novel anticancer therapies and will hopefully facilitate the testing of the clinical validity of this promising treatment method. Here we review the recent literature concerning the most frequently reported types of nanoparticles for the treatment of GB.

TERT mutations-associated alterations in clinical characteristics, immune environment and therapy response in glioblastomas

OBJECTIVE TERT: is the most frequently mutated gene in adult glioblastomas (GBMs) defined by the 2021 World Health Organization classification system. The present study aims to explore differences in clinical characteristics and immune microenvironment between TERT mutant and wild-type GBM.

METHODS

Three GBM-related cohorts consisting of 205 GBM patients in our cohort, 463 GBM patients without immune checkpoint inhibitor(ICI) therapy and 1465 tumour patients (including 92 GBM cases) receiving ICI treatment in the MSK cohort were included. Retrospective analysis and immunohistochemistry assay were used for investigating the local (including tumour cells, local immune cells, and seizures) and systemic (including circulating immune cells, coagulation-related functions, and prognosis) effects of TERT mutations. Besides, differences in genetic alterations and immunotherapy responses between TERT mutant and wild-type GBMs were also explored.

RESULTS

We found that TERT mutant and wild-type GBMs possessed similar initial clinic symptoms, circulating immune microenvironment and immunotherapy response. With respect to that in TERT wild-type GBMs, mutations in TERT resulted in higher levels of tumour-infiltrating neutrophils, prolonged coagulation time, worse chemotherapy response and poorer overall survival.

CONCLUSION

Mutations in TERT alter the local immune environment and decrease the sensitivity of GBM to chemotherapy.

Nanoparticle Strategies to Improve the Delivery of Anticancer Drugs across the Blood-Brain Barrier to Treat Brain Tumors

Primary brain and central nervous system (CNS) tumors are a diverse group of neoplasms that occur within the brain and spinal cord. Although significant advances in our understanding of the intricate biological underpinnings of CNS neoplasm tumorigenesis and progression have been made, the translation of these discoveries into effective therapies has been stymied by the unique challenges presented by these tumors' exquisitely sensitive location and the body's own defense mechanisms (e.g., the brain-CSF barrier and blood-brain barrier), which normally protect the CNS from toxic insult. These barriers effectively prevent the delivery of therapeutics to the site of disease. To overcome these obstacles, new methods for therapeutic delivery are being developed, with one such approach being the utilization of nanoparticles. Here, we will cover the current state of the field with a particular focus on the challenges posed by the BBB, the different nanoparticle classes which are under development for targeted CNS tumor therapeutics delivery, and strategies which have been developed to bypass the BBB and enable effective therapeutics delivery to the site of disease.