Engineered macrophages as near-infrared light activated drug vectors for chemo-photodynamic therapy of primary and bone metastatic breast cancer

Fucoidan based Ce6-chloroquine self-assembled hydrogel as in situ vaccines to enhance tumor immunotherapy by autophagy inhibition and macrophage polarization

Tumor vaccines have become a promising approach for cancer treatment by triggering antigen-specific responses against tumors. However, autophagy and immunosuppressive tumor microenvironment (TME) reduce antigen exposure and immunogenicity, which limit the effect of tumor vaccines. Here, we develop fucoidan (Fuc) based chlorin e6 (Ce6)-chloroquine (CQ) self-assembly hydrogels (CCFG) as in situ vaccines. Ce6 triggers immune response in situ by photodynamic therapy (PDT) induced immunogenic cell death (ICD) effect, which is further enhanced by macrophage polarization of Fuc and autophagy inhibition of CQ. In vivo studies show that CCFG effectively enhances antigen presentation under laser irradiation, which induces a powerful in situ vaccine effect and significantly inhibits tumor metastasis and recurrence. Our study provides a novel approach for enhancing tumor immunotherapy and inhibiting tumor recurrence and metastasis.

Polymeric nanocarrier via metabolism regulation mediates immunogenic cell death with spatiotemporal orchestration for cancer immunotherapy

The limited efficacy of cancer immunotherapy occurs due to the lack of spatiotemporal orchestration of adaptive immune response stimulation and immunosuppressive tumor microenvironment modulation. Herein, we report a nanoplatform fabricated using a pH-sensitive triblock copolymer synthesized by reversible addition-fragmentation chain transfer polymerization enabling in situ tumor vaccination and tumor-associated macrophages (TAMs) polarization. The nanocarrier itself can induce melanoma immunogenic cell death (ICD) via tertiary amines and thioethers concentrating on mitochondria to regulate metabolism in triggering endoplasmic reticulum stress and upregulating gasdermin D for pyroptosis as well as some features of ferroptosis and apoptosis. After the addition of ligand cyclic arginine-glycine-aspartic acid (cRGD) and mannose, the mixed nanocarrier with immune adjuvant resiquimod encapsulation can target B16F10 cells for in situ tumor vaccination and TAMs for M1 phenotype polarization. In vivo studies indicate that the mixed targeting nanoplatform elicits tumor ICD, dendritic cell maturation, TAM polarization, and cytotoxic T lymphocyte infiltration and inhibits melanoma volume growth. In combination with immune checkpoint blockade, the survival time of mice is markedly prolonged. This study provides a strategy for utilizing immunoactive materials in the innate and adaptive immune responses to augment cancer therapy.

Nanotechnology Applications in Breast Cancer Immunotherapy

Next-generation cancer treatments are expected not only to target cancer cells but also to simultaneously train immune cells to combat cancer while modulating the immune-suppressive environment of tumors and hosts to ensure a robust and lasting response. Achieving this requires carriers that can codeliver multiple therapeutics to the right cancer and/or immune cells while ensuring patient safety. Nanotechnology holds great potential for addressing these challenges. This article highlights the recent advances in nanoimmunotherapeutic development, with a focus on breast cancer. While immune checkpoint inhibitors (ICIs) have achieved remarkable success and lead to cures in some cancers, their response rate in breast cancer is low. The poor response rate in solid tumors is often associated with the low infiltration of anti-cancer T cells and an immunosuppressive tumor microenvironment (TME). To enhance anti-cancer T-cell responses, nanoparticles are employed to deliver ICIs, bispecific antibodies, cytokines, and agents that induce immunogenic cancer cell death (ICD). Additionally, nanoparticles are used to manipulate various components of the TME, such as immunosuppressive myeloid cells, macrophages, dendritic cells, and fibroblasts to improve T-cell activities. Finally, this article discusses the outlook, challenges, and future directions of nanoimmunotherapeutics.

Engineered cyanobacteria-Fe3O4 hybrid system as oxygen generator and photosensitizer production factory for synergistic cancer PDT-immunotherapy

The combination of photodynamic therapy (PDT)-immunotherapy has brought much hope for cancer patients. However, the hypoxia tumor microenvironment (TME) can regulate tumor angiogenesis and inhibit immune response, thus limiting the therapeutic effects. In this paper, engineered cyanobacteria-M2-like tumor-associated macrophages (TAMs) targeting peptide modified Fe3O4 nanoparticles hybrid system (ECyano@Fe3O4-M2pep) was constructed for alleviating hypoxia and relieving immune suppression to achieve synergistic cancer PDT-immunotherapy. With the irradiation of red laser, oxygen was produced by the photosynthesis of ECyano to alleviate the hypoxia TME. Then, ECyano could secret 5-aminolevulinic acid (5-ALA) under the induction of theophylline for controllable PDT. In the process of PDT, the disulfide bond between ECyano and Fe3O4-M2pep was broken in response to reactive oxygen species (ROS), and then Fe3O4-M2pep was released to target M2-like TAMs, corresponding by the polarization of M2-like TAMs to M1-like TAMs for the killing of tumor cells. Compared with other groups, ECyano@Fe3O4-M2pep + theophylline + laser (ECyano@Fe3O4-M2pep + T + L) group displayed the lowest tumor volume (159.3 mm3) and the highest M1/M2 ratio (1.25- fold). We believe that this hybrid system will offer a promising way for the biomedical application of bacterial therapy.

A Biomimetic Autophagosomes-Based Nanovaccine Boosts Anticancer Immunity

Personalized cancer vaccines based on tumor cell lysates offer promise for cancer immunotherapy yet fail to elicit a robust therapeutic effect due to the weak immunogenicity of tumor antigens. Autophagosomes, obtained from pleural effusions and ascites of cancer patients, have been identified as abundant reservoirs of tumor neoantigens that exhibit heightened immunogenicity. However, their potential as personalized cancer vaccines have been constrained by suboptimal lymphatic-targeting performances and challenges in antigen-presenting cell endocytosis. Here,a reinforced biomimetic autophagosome-based (BAPs) nanovaccine generated by precisely amalgamating autophagosome-derived neoantigens and two types of adjuvants capable of targeting lymph nodes is developed to potently elicit antitumor immunity. The redox-responsive BAPs facilitate cytosolic vaccine opening within antigen-presenting cells, thereby exposing adjuvants and antigens to stimulate a strong immune response. BAPs evoke broad-spectrum T-cell responses, culminating in the effective eradication of 71.4% of established tumors. Notably, BAPs vaccination triggers enduring T-cell responses that confer robust protection, with 100% of mice shielded against tumor rechallenge and a significant reduction in tumor incidence by 87.5%. Furthermore, BAPs synergize with checkpoint blockade therapy to inhibit tumor growth in the poorly immunogenic breast cancer model. The biomimetic approach presents a powerful nanovaccine formula with high versatility for personalized cancer immunotherapy.

Tumor microenvironment-responsive macrophage-mediated immunotherapeutic drug delivery

Immunotherapy, as a promising treatment strategy for cancer, has been widely employed in clinics, while its efficiency is limited by the immunosuppression of tumor microenvironment (TME). Tumor-associate macrophages (TAMs) are the most abundant immune cells infiltrating the TME and play a crucial role in immune regulation. Herein, a M0-type macrophage-mediated drug delivery system (PR-M) was designed for carrying Toll-like receptors (TLRs) agonist-loaded nanoparticles. When TLR agonist R848 was released by responding to the TME, the PR-Ms were polarized from M0-type to M1-type and TAMs were also stimulated from M2-type to M1-type, which eventually reversed the immunosuppressive states of TME. By synergizing with the released R848 agonists, the PR-M significantly activated CD4+ and CD8+ T cells in the TME and turned the 'cold' tumor into 'hot' tumor by regulating the secretion of cytokines including IFN-γ, TNF-α, IL-10, and IL-12, thus ultimately promoting the activation of antitumor immunity. In a colorectal cancer mouse model, the PR-M treatment effectively accumulated at the tumor site, with a 5.47-fold increase in M1-type and a 65.08 % decrease in M2-type, resulting in an 85.25 % inhibition of tumor growth and a 87.55 % reduction of tumor volume compared with the non-treatment group. Our work suggests that immune cell-mediated drug delivery systems can effectively increase drug accumulation at the tumor site and reduce toxic side effects, resulting in a strong immune system for tumor immunotherapy. STATEMENT OF SIGNIFICANCE: The formation of TME and the activation of TAMs create an immunosuppressive network that allows tumor to escape the immune system and promotes its growth and spread. In this study, we designed an M0-type macrophage-mediated drug delivery system (PR-M). It leverages the synergistic effect of macrophages and agonists to improve the tumor immunosuppressive micro-environment by increasing M1-type macrophages and decreasing M2-type macrophages. As part of the treatment, the drug-loaded macrophages endowed the system with excellent tumor targeting. Furthermore, loading R848 into TME-responsive nanoparticles could protect macrophages and reduce the potential toxicity of agonists. Further investigations demonstrated that the designed PR-M could be a feasible strategy with high efficacy in tumor targeting, drug loading, autoimmunity activation, and lower side effects.

Effect of pelvic floor muscle exercise combined with infrared physiotherapy on postpartum urinary incontinence

BACKGROUND

Scientific treatments for postpartum urinary incontinence, including pelvic floor muscle exercises (such as Kegel exercises) and infrared therapy, can effectively improve pelvic floor and urethral function, thus enhancing quality of life. However, clinical research on the combined use of these interventions for postpartum urinary incontinence is limited.

OBJECTIVE

To investigate the combining efficacy of pelvic floor muscle exercises with infrared physiotherapy on postpartum urinary incontinence.

METHODS

Clinical information of 102 patients with postpartum urinary incontinence (June 2021-June 2022) were collected and analyzed. Patients were randomly divided into control (conventional intervention) and observation (pelvic floor muscle exercises combined with infrared physiotherapy) groups, with 52 and 50 cases respectively. We compared pelvic floor muscle strength, urodynamic indicators, leakage volume, quality of life, and overall clinical efficacy between the two groups.

RESULTS

Before intervention, both groups had similar pelvic floor function scores and urodynamic indicators. Post-intervention, the pelvic floor function scores in the observation group were significantly lower than control. The urodynamic indicator levels of the observation group were markedly higher than control after 2 months of intervention. Leakage volume was similar before intervention, while the observation group had significantly lower volumes after 1 and 2 months of intervention. Quality of life scores were similar initially, but after 2 months, the observation group scored higher. The observation group showed notably better pelvic floor rehabilitation at 2 months post-intervention.

CONCLUSION

Combining pelvic floor muscle exercise with infrared physiotherapy has been shown to be a highly effective approach in enhancing pelvic floor muscle strength and improving the quality of life for postpartum women experiencing urinary incontinence. This combined therapy also demonstrates positive effects on urodynamic indicators, reducing leakage volume, and facilitating pelvic floor rehabilitation.

Empowering brain tumor management: chimeric antigen receptor macrophage therapy

Brain tumors pose formidable challenges in oncology due to the intricate biology and the scarcity of effective treatment modalities. The emergence of immunotherapy has opened new avenues for innovative therapeutic strategies. Chimeric antigen receptor, originally investigated in T cell-based therapy, has now expanded to encompass macrophages, presenting a compelling avenue for augmenting anti-tumor immune surveillance. This emerging frontier holds promise for advancing the repertoire of therapeutic options against brain tumors, offering potential breakthroughs in combating the formidable malignancies of the central nervous system. Tumor-associated macrophages constitute a substantial portion, ranging from 30% to 50%, of the tumor tissue and exhibit tumor-promoting phenotypes within the immune-compromised microenvironment. Constructing CAR-macrophages can effectively repolarize M2-type macrophages towards an M1-type phenotype, thereby eliciting potent anti-tumor effects. CAR-macrophages can recruit T cells to the brain tumor site, thereby orchestrating a remodeling of the immune niche to effectively inhibit tumor growth. In this review, we explore the potential limitations as well as strategies for optimizing CAR-M therapy, offering insights into the future direction of this innovative therapeutic approach.

Nanomaterials for bone metastasis

Bone metastasis, a prevalent occurrence in primary malignant tumors, is often associated with a grim prognosis. The bone microenvironment comprises various coexisting cell types, working together in a coordinated manner. This dynamic microenvironment plays a pivotal role in the initiation and progression of bone metastases. While cancer therapies have made advancements, the available options for addressing bone metastases remain insufficient. The advent of nanotechnology has ushered in a new era for managing and preventing bone metastases because of the physicochemical and adaptable advantages of nanoplatforms. In this review, we make an introduction of the underlying mechanisms and the current clinical therapies of bone metastases, highlighting the advances of intelligent nanosystems that can stimulate vascular regeneration, promote bone regeneration, eliminate tumor cells, minimize bone damage, and expedite bone healing. The innovation surrounding bone-targeting nanoplatforms presents a fresh approach to the theranostics of bone metastases.

Optimized Bionic Drug-Delivery-Inducing Immunogenic Cell Death and cGAS-STING Pathway Activation for Enhanced Photodynamic-Chemotherapy-Driven Immunotherapy in Prostate Cancer

Prostate cancer presents as a challenging disease, as it is often characterized as an immunologically "cold" tumor, leading to suboptimal outcomes with current immunotherapeutic approaches in clinical settings. Photodynamic therapy (PDT) harnesses reactive oxygen species generated by photosensitizers (PSs) to disrupt the intracellular redox equilibrium. This process induces DNA damage in both the mitochondria and nucleus, activating the process of immunogenic cell death (ICD) and the cGAS-STING pathway. Ultimately, this cascade of events leads to the initiation of antitumor immune responses. Nevertheless, existing PSs face challenges, including suboptimal tumor targeting, aggregation-induced quenching, and insufficient oxygen levels in the tumor regions. To this end, a versatile bionic nanoplatform has been designed for the simultaneous delivery of the aggregation-induced emission PS TPAQ-Py-PF6 and paclitaxel (PTX). The cell membrane camouflage of the nanoplatform leads to its remarkable abilities in tumor targeting and cellular internalization. Upon laser irradiation, the utilization of TPAQ-Py-PF6 in conjunction with PTX showcases a notable and enhanced synergistic antitumor impact. Additionally, the nanoplatform has the capability of initiating the cGAS-STING pathway, leading to the generation of cytokines. The presence of damage-associated molecular patterns induced by ICD collaborates with these aforementioned cytokines lead to the recruitment and facilitation of dendritic cell maturation. Consequently, this elicits a systemic immune response against tumors. In summary, this promising strategy highlights the use of a multifunctional biomimetic nanoplatform, combining chemotherapy, PDT, and immunotherapy to enhance the effectiveness of antitumor treatment.

Theoretical basis, state and challenges of living cell-based drug delivery systems

The therapeutic efficacy of drugs is determined, to a certain extent, by the efficiency of drug delivery. The low efficiency of drug delivery systems (DDSs) is frequently associated with serious toxic side effects and can even prove fatal in certain cases. With the rapid development of technology, drug delivery has evolved from using traditional frameworks to using nano DDSs (NDDSs), endogenous biomaterials DDSs (EBDDSs), and living cell DDSs (LCDDSs). LCDDSs are receiving widespread attention from researchers at present owing to the unique advantages of living cells in targeted drug delivery, including their excellent biocompatibility properties, low immunogenicity, unique biological properties and functions, and role in the treatment of diseases. However, the theoretical basis and techniques involved in the application of LCDDSs have not been extensively summarized to date. Therefore, this review comprehensively summarizes the properties and applications of living cells, elaborates the various drug loading approaches and controlled drug release, and discusses the results of clinical trials. The review also discusses the current shortcomings and prospects for the future development of LCDDSs, which will serve as highly valuable insights for the development and clinical transformation of LCDDSs in the future.

The Evolution of Microfluidic-Based Drug-Loading Techniques for Cells and Their Derivatives

Conventional drug delivery techniques face challenges related to targeting and adverse reactions. Recent years have witnessed significant advancements in nanoparticle-based drug carriers. Nevertheless, concerns persist regarding their safety and insufficient metabolism. Employing cells and their derivatives, such as cell membranes and extracellular vesicles (EVs), as drug carriers effectively addresses the challenges associated with nanoparticle carriers. However, an essential hurdle remains in efficiently loading drugs into these carriers. With the advancement of microfluidic technology and its advantages in precise manipulation at the micro- and nanoscales, as well as minimal sample loss, it has found extensive application in the loading of drugs using cells and their derivatives, thereby fostering the development of drug-loading techniques. This paper outlines the characteristics and benefits of utilizing cells and their derivatives as drug carriers and provides an overview of current drug-loading techniques, particularly those rooted in microfluidic technology. The significant potential for microfluidic technology in targeted disease therapy through drug delivery systems employing cells and their derivatives, is foreseen.

Macrophage polarization in the tumor microenvironment: Emerging roles and therapeutic potentials

The tumor microenvironment (TME) is a combination of tumor cells and indigenous host stroma, which consists of tumor-infiltrating immune cells, endothelial cells, fibroblasts, pericytes, and non-cellular elements. Tumor-associated macrophages (TAMs) represent the major tumor-infiltrating immune cell type and are generally polarized into two functionally contradictory subtypes, namely classical activated M1 macrophages and alternatively activated M2 macrophages. Macrophage polarization refers to how macrophages are activated at a given time and space. The interplay between the TME and macrophage polarization can influence tumor initiation and progression, making TAM a potential target for cancer therapy. Here, we review the latest investigations on factors orchestrating macrophage polarization in the TME, how macrophage polarization affects tumor progression, and the perspectives in modulating macrophage polarization for cancer immunotherapy.

Macrophage based drug delivery: Key challenges and strategies

As a natural immune cell and antigen presenting cell, macrophages have been studied and engineered to treat human diseases. Macrophages are well-suited for use as drug carriers because of their biological characteristics, such as excellent biocompatibility, long circulation, intrinsic inflammatory homing and phagocytosis. Meanwhile, macrophages' uniquely high plasticity and easy re-education polarization facilitates their use as part of efficacious therapeutics for the treatment of inflammatory diseases or tumors. Although recent studies have demonstrated promising advances in macrophage-based drug delivery, several challenges currently hinder further improvement of therapeutic effect and clinical application. This article focuses on the main challenges of utilizing macrophage-based drug delivery, from the selection of macrophage sources, drug loading, and maintenance of macrophage phenotypes, to drug migration and release at target sites. In addition, corresponding strategies and insights related to these challenges are described. Finally, we also provide perspective on shortcomings on the road to clinical translation and production.

Nanoparticles destabilizing the cell membranes triggered by NIR light for cancer imaging and photo-immunotherapy

Cationic polymers have great potential for cancer therapy due to their unique interactions with cancer cells. However, their clinical application remains limited by their high toxicity. Here we show a cell membrane-targeting cationic polymer with antineoplastic activity (Pmt) and a second near-infrared (NIR-II) fluorescent biodegradable polymer with photosensitizer Bodipy units and reactive oxygen species (ROS) responsive thioketal bonds (PBodipy). Subsequently, these two polymers can self-assemble into antineoplastic nanoparticles (denoted mt-NPBodipy) which could further accumulate at the tumor and destroy cell membranes through electrostatic interactions, resulting in cell membrane destabilization. Meanwhile, the photosensitizer Bodipy produces ROS to induce damage to cell membranes, proteins, and DNAs to kill cancer cells concertedly, finally resulting in cell membrane lysis and cancer cell death. This work highlights the use of near-infrared light to spatially and temporarily control cationic polymers for photodynamic therapy, photo-immunotherapy, and NIR-II fluorescence for bio-imaging.

Macrophages-mediated delivery of protoporphyrin for sonodynamic therapy of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by infiltration of inflammatory cells, hyperplasia of synovium, and destruction of the joint cartilage. Owing to the low drug delivery efficiency and limited immunosuppression effect, complete cure for RA remains a formidable challenge. Here, we show that live macrophages (Mφs) carrying protoporphyrin-loaded Fe3O4 nanoparticles can migrate to the RA tissues and inhibit the inflammation by sonodynamic therapy. The inflammation of RA leads to the release of cytokines, which guides the migration of the Mφs into the RA tissues, realizing precise delivery of therapeutics. The following sonodynamic therapy induced by ultrasound and protoporphyrin destructs the proliferating synovial cells and also infiltrated inflammatory cells, demonstrating significant therapeutic effect for RA. Meanwhile, the cytokines and relapse of RA can be remarkably suppressed because of the efficient damage to the resident inflammatory cells.

Self-Generating Gold Nanocatalysts in Autologous Tumor Cells for Targeted Catalytic Immunotherapy

Employing tumor whole cells for tumor immunotherapy is a promising tumor therapy proposed in the early stage, but its therapeutic efficacy is weakened by the methods of eliminating pathogenicity and the mass ratio of the effective antigen carried by itself. Here, by adding gold ion to live cancer cells in the microfluidic droplets, this work obtains dead tumor whole cells with NIR-controlled catalytic ability whose pathogenicity is removed while plenary tumor antigens, major structure, and homing ability are reserved. The engineered tumor cell (Cell-Au) with the addition of prodrug provides 1O2 in an O2-free Russell mechanism, which serves better in a hypoxic tumor microenvironment. This tumor whole-cell catalytic vaccine (TWCV) promotes the activation of dendritic cells and the transformation of macrophages into tumor suppressor phenotype. In 4T1 tumor-bearing mice, the Cell-Au-based vaccine supports the polarization of cytotoxicity T cells, resulting in tumor eradication and long-term animal survival. Compared with antigen vaccines or adoptive cell therapy which takes months to obtain, this TWCV can be prepared in just a few days with satisfactory immune activation and tumor therapeutic efficacy, which provides an alternative way for the preparation of personalized tumor vaccines across tumor types and gives immunotherapy a new path.

Magnetic Microrobots for In Vivo Cargo Delivery: A Review

Magnetic microrobots, with their small size and agile maneuverability, are well-suited for navigating the intricate and confined spaces within the human body. In vivo cargo delivery within the context of microrobotics involves the use of microrobots to transport and administer drugs and cells directly to the targeted regions within a living organism. The principal aim is to enhance the precision, efficiency, and safety of therapeutic interventions. Despite their potential, there is a shortage of comprehensive reviews on the use of magnetic microrobots for in vivo cargo delivery from both research and engineering perspectives, particularly those published after 2019. This review addresses this gap by disentangling recent advancements in magnetic microrobots for in vivo cargo delivery. It summarizes their actuation platforms, structural designs, cargo loading and release methods, tracking methods, navigation algorithms, and degradation and retrieval methods. Finally, it highlights potential research directions. This review aims to provide a comprehensive summary of the current landscape of magnetic microrobot technologies for in vivo cargo delivery. It highlights their present implementation methods, capabilities, and prospective research directions. The review also examines significant innovations and inherent challenges in biomedical applications.

CAR-macrophage versus CAR-T for solid tumors: The race between a rising star and a superstar

Adoptive cell therapy (ACT) has been demonstrated to be one of the most promising cancer immunotherapy strategies due to its active antitumor capabilities in vivo. Engineering T cells to overexpress chimeric antigen receptors (CARs), for example, has shown potent efficacy in the therapy of some hematologic malignancies. However, the efficacy of chimeric antigen receptor T cell (CAR-T) therapy against solid tumors is still limited due to the immunosuppressive tumor microenvironment (TME) of solid tumors, difficulty in infiltrating tumor sites, lack of tumor-specific antigens, antigen escape, and severe side effects. In contrast, macrophages expressing CARs (CAR-macrophages) have emerged as another promising candidate in immunotherapy, particularly for solid tumors. Now at its nascent stage (with only one clinical trial progressing), CAR-macrophage still shows inspiring potential advantages over CAR-T in treating solid tumors, including more abundant antitumor mechanisms and better infiltration into tumors. In this review, we discuss the relationships and differences between CAR-T and CAR-macrophage therapies in terms of their CAR structures, antitumor mechanisms, challenges faced in treating solid tumors, and insights gleaned from clinical trials and practice for solid tumors. We especially highlight the potential advantages of CAR-macrophage therapy over CAR-T for solid tumors. Understanding these relationships and differences provides new insight into possible optimization strategies of both these two therapies in solid tumor treatment.

Bacteria Synergized with PD-1 Blockade Enhance Positive Feedback Loop of Cancer Cells-M1 Macrophages-T Cells in Glioma

Cancer immunotherapy is an attractive strategy because it stimulates immune cells to target malignant cells by regulating the intrinsic activity of the immune system. However, due to lacking many immunologic markers, it remains difficult to treat glioma, a representative "cold" tumor. Herein, to wake the "hot" tumor immunity of glioma, Porphyromonas gingivalis (Pg) is customized with a coating to create an immunogenic tumor microenvironment and further prove the effect in combination with the immune checkpoint agent anti-PD-1, exhibiting elevated therapeutic efficacy. This is accomplished not by enhancing the delivery of PD-1 blockade to enhance the effect of immunotherapy, but by introducing bacterial photothermal therapy to promote greater involvement of M1 cells in the immune response. After reaching glioma, the bacteria further target glioma cells and M2 phenotype macrophages selectively, enabling precise photothermal conversion for lysing tumor cells and M2 phenotype macrophages, which thereby enhances the positive feedback loop of cancer cells-M1 macrophages-T cells. Collectively, the bacteria synergized with PD-1 blockade strategy may be the key to overcoming the immunosuppressive glioma microenvironment and improving the outcome of immunotherapy toward glioma.

Chimeric Peptide-Engineered Self-Delivery Nanomedicine for Photodynamic-Triggered Breast Cancer Immunotherapy by Macrophage Polarization

A systemic treatment strategy is urgently demanded to suppress the rapid growth and easy metastasis characteristics of breast cancer. In this work, a chimeric peptide-engineered self-delivery nanomedicine (designated as ChiP-CeR) for photodynamic-triggered breast cancer immunotherapy by macrophage polarization. Among these, ChiP-CeR is composed of the photosensitizer of chlorine e6 (Ce6) and the TLR7/8 agonist of lmiquimod (R837), which is further modified with tumor matrix targeting peptide (Fmoc-K(Fmoc)-PEG8-CREKA. ChiP-CeR is preferred to actively accumulate at the tumor site via specific recognition of fibronectin, which can eradicate primary tumor growth through photodynamic therapy (PDT). Meanwhile, the destruction of primary tumors would trigger immunogenic cell death (ICD) effects to release high-mobility group box-1(HMGB1) and expose calreticulin (CRT). Moreover, ChiP-CeR can also polarize M2-type tumor-associated macrophages (TAMs) into M1-type TAMs, which can activate T cell antitumor immunity in combination with ICD. Overall, ChiP-CeR possesses superior antitumor effects against primary and lung metastatic tumors, which provide an applicable nanomedicine and a feasible strategy for the systemic management of metastatic breast cancer.

Nanodrug Delivery Systems in Antitumor Immunotherapy

Cancer has become one of the most important factors threatening human health, and the global cancer burden has been increasing rapidly. Immunotherapy has become another clinical research hotspot after surgery, chemotherapy, and radiotherapy because of its high efficiency and tumor metastasis prevention. However, problems such as lower immune response rate and immune-related adverse reaction in the clinical application of immunotherapy need to be urgently solved. With the development of nanodrug delivery systems, various nanocarrier materials have been used in the research of antitumor immunotherapy with encouraging therapeutic results. In this review, we mainly summarized the combination of nanodrug delivery systems and immunotherapy from the following 4 aspects: (a) nanodrug delivery systems combined with cytokine therapy to improve cytokines delivery in vivo; (b) nanodrug delivery systems provided a suitable platform for the combination of immune checkpoint blockade therapy with other tumor treatments; (c) nanodrug delivery systems helped deliver antigens and adjuvants for tumor vaccines to enhance immune effects; and (d) nanodrug delivery systems improved tumor treatment efficiency and reduced toxicity for adoptive cell therapy. Nanomaterials chosen by researchers to construct nanodrug delivery systems and their function were also introduced in detail. Finally, we discussed the current challenges and future prospects in combining nanodrug delivery systems with immunotherapy.

Macrophage heterogeneity in bone metastasis

Previous studies illustrated that macrophage, a type of innate immune cell, plays critical roles in tumour progression and metastasis. Bone is the most frequent site of metastasis for several cancer types including breast, prostate, and lung. In bone metastasis, osteoclast, a macrophage subset specialized in bone resorption, was heavily investigated in the past. Recent studies illustrated that other macrophage subsets, e.g. monocyte-derived macrophages, and bone resident macrophages, promoted bone metastasis independent of osteoclast function. These novel mechanisms further improved our understanding of macrophage heterogeneity in the context of bone metastasis and illustrated new opportunities for future studies.

Advances in Engineered Macrophages: A New Frontier in Cancer Immunotherapy

Macrophages, as pivotal cells within the tumour microenvironment, significantly influence the impact of and reactions to treatments for solid tumours. The rapid evolution of bioengineering technology has revealed the vast potential of engineered macrophages in immunotherapy, disease diagnosis, and tissue engineering. Given this landscape, the goal of harnessing and innovating macrophages as a novel strategy for solid tumour immunotherapy cannot be overstated. The diverse strategies for engineered macrophages in the realm of cancer immunotherapy, encompassing macrophage drug delivery systems, chimeric antigen receptor macrophage therapy, and synergistic treatment approaches involving bacterial outer membrane vesicles and macrophages, are meticulously examined in this review. These methodologies are designed to enhance the therapeutic efficacy of macrophages against solid tumours, particularly those that are drug-resistant and metastatic. Collectively, these immunotherapies are poised to supplement and refine current solid tumour treatment paradigms, thus heralding a new frontier in the fight against malignant tumours.

Enhancing photodynamic immunotherapy by reprograming the immunosuppressive tumor microenvironment with hypoxia relief

Tumor hypoxia impairs the generation of reactive oxygen species and the induction of immunogenic cell death (ICD) for photodynamic therapy (PDT), thus impeding its efficacy and the subsequent immunotherapy. In addition, hypoxia plays a critical role in forming immunosuppressive tumor microenvironments (TME) by regulating the infiltration of immunosuppressive tumor-associated macrophages (TAMs) and the expression of programmed death ligand 1 (PD-L1). To simultaneously tackle these issues, a MnO2-containing albumin nanoplatform co-delivering IR780, NLG919, and a paclitaxel (PTX) dimer is designed to boost photodynamic immunotherapy. The MnO2-catalyzed oxygen supply bolsters the efficacy of PDT and PTX-mediated chemotherapy, collectively amplifying the induction of ICD and the expansion of tumor-specific cytotoxic T lymphocytes (CTLs). More importantly, hypoxia releif reshapes the immunosuppressive TME via down-regulating the intratumoral infiltration of M2-type TAMs and the PD-L1 expression of tumor cells to enhance the infiltration and efficacy of CTLs in combination with immune checkpoint blockade (ICB) by NLG919, consequently eradicating primary tumors and almost completely preventing tumor relapse and metastasis. This study sets an example of enhanced immunotherapy for breast cancers through dual ICD induction and simultaneous immunosuppression modulation via both hypoxia relief and ICB, providing a strategy for the treatment of other hypoxic and immunosuppressive cancers.

Recent Advances in Reprogramming Strategy of Tumor Microenvironment for Rejuvenating Photosensitizers-Mediated Photodynamic Therapy

Photodynamic therapy (PDT) has recently been considered a potential tumor therapy due to its time-space specificity and non-invasive advantages. PDT can not only directly kill tumor cells by using cytotoxic reactive oxygen species but also induce an anti-tumor immune response by causing immunogenic cell death of tumor cells. Although it exhibits a promising prospect in treating tumors, there are still many problems to be solved in its practical application. Tumor hypoxia and immunosuppressive microenvironment seriously affect the efficacy of PDT. The hypoxic and immunosuppressive microenvironment is mainly due to the abnormal vascular matrix around the tumor, its abnormal metabolism, and the influence of various immunosuppressive-related cells and their expressed molecules. Thus, reprogramming the tumor microenvironment (TME) is of great significance for rejuvenating PDT. This article reviews the latest strategies for rejuvenating PDT, from regulating tumor vascular matrix, interfering with tumor cell metabolism, and reprogramming immunosuppressive related cells and factors to reverse tumor hypoxia and immunosuppressive microenvironment. These strategies provide valuable information for a better understanding of the significance of TME in PDT and also guide the development of the next-generation multifunctional nanoplatforms for PDT.

Doxorubicin-Loaded Microalgal Delivery System for Combined Chemotherapy and Enhanced Photodynamic Therapy of Osteosarcoma

Osteosarcoma (OS) is considered the most frequent type of primary malignant bone tumor. Currently, radiotherapy, photodynamic (PDT), and other therapies for osteosarcoma are limited by tumor hypoxia and single efficacy and serve side-effects. Herein, we reported a microalgal drug delivery system (SpiD), doxorubicin (DOX)-loaded Spirulina platensis (Spi) for OS therapy. The specific surface of Spirulina platensis allowed for effective loading of DOX via surface channels and electrostatic interactions. Under 650 nm laser irradiation, SpiD enabled high oxygen production by photosynthesis and enhanced reactive oxygen species (ROS) generation via chlorophyll-assisted photosensitization, synergistically killing tumor cells with the released DOX. Combined chemotherapy and enhanced PDT mediated by SpiD exerted synergic antitumor effects and resulted in potent therapeutic efficacy in orthotopic osteosarcoma mice. Furthermore, SpiD could reduce the side-effects of chemotherapy, showing excellent blood and tissue safety. Taken together, this microalgal drug delivery system provided a natural, efficient, safe, and inexpensive strategy for OS treatment.

Nanocarriers in topical photodynamic therapy

INTRODUCTION

Photodynamic therapy (PDT) has gained significant attention due to its superiority over conventional treatments. In the context of skin cancers and nonmalignant skin diseases, topical application of photosensitizer formulations onto affected skin, followed by illumination, offers distinct advantages. Topical PDT simplifies therapy by providing easy access to the skin, increasing drug concentration within the target area, and confining residual photosensitivity to the treated skin. However, the effectiveness of topical PDT is often hindered by challenges such as limited skin penetration or photosensitizer instability. Additionally, the hypoxic tumor environment poses further limitations. Nanocarriers present a promising solution to address these challenges.

AREAS COVERED

The objective of this review is to comprehensively explore and highlight the role of various nanocarriers in advancing topical PDT for the treatment of skin diseases. The primary focus is to address the challenges associated with conventional topical PDT approaches and demonstrate how nanotechnology-based strategies can overcome these challenges, thereby improving the overall efficiency and efficacy of PDT.

EXPERT OPINION

Nanotechnology has revolutionized the field of PDT, offering innovative tools to combat the unfavorable features of photosensitizers and hurdles in PDT. Nanocarriers enhance skin penetration and stability of photosensitizers, provide controlled drug release, reduce needed dose, increase production of reactive oxygen species, while reducing side effects, thereby improving PDT effectiveness.

Reducing Cholesterol Level in Live Macrophages Improves Delivery Performance by Enhancing Blood Shear Stress Adaptation

In recent years, live-cell-based drug delivery systems have gained considerable attention. However, shear stress, which accompanies blood flow, may cause cell death and weaken the delivery performance. In this study, we found that reducing cholesterol in macrophage plasma membranes enhanced their tumor targeting ability by more than 2-fold. Our study demonstrates that the reduced cholesterol level deactivated the mammalian target of rapamycin (mTOR) and consequently promoted the nuclear translocation of transcription factor EB (TFEB), which in turn enhanced the expression of superoxide dismutase (SOD) to reduce reactive oxygen species (ROS) induced by shear stress. A proof-of-concept system using low cholesterol macrophages attached to MXene (e.g., l-RX) was fabricated. In a melanoma mouse model, l-RX and laser irradiation treatments eliminated tumors with no recurrences observed in mice. Therefore, cholesterol reduction is a simple and effective way to enhance the targeting performance of macrophage-based drug delivery systems.

Beyond boundaries: unraveling innovative approaches to combat bone-metastatic cancers

Evidence demonstrated that bones, liver, and lungs are the most common metastasis sites in some human malignancies, especially in prostate and breast cancers. Bone is the third most frequent target for spreading tumor cells among these organs and tissues. Patients with bone-metastatic cancers face a grim prognosis characterized by short median survival time. Current treatments have proven insufficient, as they can only inhibit metastasis or tumor progression within the bone tissues rather than providing a curative solution. Gaining a more profound comprehension of the interplay between tumor cells and the bone microenvironment (BME) is of utmost importance in tackling this issue. This knowledge will pave the way for developing innovative diagnostic and therapeutic approaches. This review summarizes the mechanisms underlying bone metastasis and discusses the clinical aspects of this pathologic condition. Additionally, it highlights emerging therapeutic interventions aimed at enhancing the quality of life for patients affected by bone-metastatic cancers. By synthesizing current research, this review seeks to shed light on the complexities of bone metastasis and offer insights for future advancements in patient care.

Metal-polyphenol "prison" attenuated bacterial outer membrane vesicle for chemodynamics promoted in situ tumor vaccines

As natural adjuvants, the bacterial outer membrane vesicles (OMV) hold great potential in cancer vaccines. However, the inherent immunotoxicity of OMV and the rarity of tumor-specific antigens seriously hamper the clinical translation of OMV-based cancer vaccines. Herein, metal-phenolic networks (MPNs) are used to attenuate the toxicity of OMV, meanwhile, provide tumor antigens via the chemodynamic effect induced immunogenic cell death (ICD). Specifically, MPNs are assembled on the OMV surface through the coordination reaction between ferric ions and tannic acid. The iron-based "prison" is locally collapsed in the tumor microenvironment (TME) with both low pH and high ATP features, and thus the systemic toxicity of OMV is significantly attenuated. The released ferric ions in TME promote the ICD of cancer cells through Fenton reaction and then the generation of abundant tumor antigens, which can be used to fabricate in-situ vaccines by converging with OMV. Together with the immunomodulatory effect of OMV, potent tumor repression on a bilateral tumor model is achieved with good biosafety.

Zuogui pill disrupt the malignant cycle in breast cancer bone metastasis through the Piezo1-Notch-1-GPX4 pathway and active molecules fishing

BACKGROUND

Breast cancer bone metastasis is closely associated with the bone microenvironment. Zuogui Pill (ZGP), a clinically approved formulation in China, effectively regulates the bone microenvironment for the prevention and treatment of osteoporosis.

PURPOSE

Few reports have utilized the ZGP for bone metastasis models. This study investigated the intervention and bone-protective properties of ZGP against breast cancer bone metastasis, explored the potential mechanism, and screened for its active compositions by molecules fishing.

METHODS

To investigate the intervention efficacy of ZGP and its protein-level mechanism of action, the mouse bone metastasis model and in vitro cell co-culture model were constructed. Affinity ultrafiltration, molecular docking, cellular thermal shift assay and physical scale detection were used to investigate the affinity components of the RANKL protein in ZGP.

RESULTS

The administration of ZGP combined with zoledronic acid inhibited the development of tumors and secondary lung metastasis in mice. This translated to a prolonged survival period and enhanced quality of life. ZGP could disrupt the malignant cycle by modulating the Piezo1-Notch-1-GPX4 signaling pathway in the "bone-cancer" communication in the cell co-culture model. Furthermore, 25 chemical components of ZGP were identified, with 10 active compounds exhibiting significant affinity for the RANKL protein.

CONCLUSION

The findings of this work highlighted ZGP's potential for intervening in the progression of breast cancer bone metastasis. Thus, this investigation served as an experimental foundation for expanding the application scope of ZGP and for advancing drug development efforts in bone metastasis treatment.

The One-Stop Integrated Nanoagent Based on Photothermal Therapy for Deep Infection Healing and Inflammation Inhibition

Chronic wounds caused by bacterial infections are a major challenge in medical fields. The hypoxia condition extremely induces reactive oxygen species (ROS) generation and upregulates the expression of hypoxia-inducible factor, both of which can increase the pro-inflammatory M1 subtype macrophages production while reducing the anti-inflammatory M2 subtype macrophages. Besides, bacteria-formed biofilms can hinder the penetration of therapeutic agents. Encouraged by natural motors automatically executing tasks, hypothesized that supplying sufficient oxygen (O2 ) would simultaneously drive therapeutic agent movement, rescue the hypoxic microenvironment, and disrupt the vicious cycle of inflammation. Here, small organic molecule-based nanoparticles (2TT-mC6B@Cu5.4 O NPs) that possess high photothermal conversion efficiency and enzymatic activities are developed, including superoxide dismutase-, catalase-, and glutathione peroxidase-like activity. 2TT-mC6B@Cu5.4 O NPs exhibit superior ROS-scavenging and O2 production abilities that synergistically relieve inflammation, alleviate hypoxia conditions, and promote their deep penetration in chronic wound tissues. Transcriptome analysis further demonstrates that 2TT-mC6B@Cu5.4O NPs inhibit biological activities inside bacteria. Furthermore, in vivo experiments prove that 2TT-mC6B@Cu5.4 O NPs-based hyperthermia can effectively eliminate bacteria in biofilms to promote wound healing.

Phototherapy techniques for the management of musculoskeletal disorders: strategies and recent advances

Musculoskeletal disorders (MSDs), which include a range of pathologies affecting bones, cartilage, muscles, tendons, and ligaments, account for a significant portion of the global burden of disease. While pharmaceutical and surgical interventions represent conventional approaches for treating MSDs, their efficacy is constrained and frequently accompanied by adverse reactions. Considering the rising incidence of MSDs, there is an urgent demand for effective treatment modalities to alter the current landscape. Phototherapy, as a controllable and non-invasive technique, has been shown to directly regulate bone, cartilage, and muscle regeneration by modulating cellular behavior. Moreover, phototherapy presents controlled ablation of tumor cells, bacteria, and aberrantly activated inflammatory cells, demonstrating therapeutic potential in conditions such as bone tumors, bone infection, and arthritis. By constructing light-responsive nanosystems, controlled drug delivery can be achieved to enable precise treatment of MSDs. Notably, various phototherapy nanoplatforms with integrated imaging capabilities have been utilized for early diagnosis, guided therapy, and prognostic assessment of MSDs, further improving the management of these disorders. This review provides a comprehensive overview of the strategies and recent advances in the application of phototherapy for the treatment of MSDs, discusses the challenges and prospects of phototherapy, and aims to promote further research and application of phototherapy techniques.

Macrophage-Based Microrobots for Anticancer Therapy: Recent Progress and Future Perspectives

Macrophages, which are part of the mononuclear phagocytic system, possess sensory receptors that enable them to target cancer cells. In addition, they are able to engulf large amounts of particles through phagocytosis, suggesting a potential "Trojan horse" drug delivery approach to tumors by facilitating the engulfment of drug-hidden particles by macrophages. Recent research has focused on the development of macrophage-based microrobots for anticancer therapy, showing promising results and potential for clinical applications. In this review, we summarize the recent development of macrophage-based microrobot research for anticancer therapy. First, we discuss the types of macrophage cells used in the development of these microrobots, the common payloads they carry, and various targeting strategies utilized to guide the microrobots to cancer sites, such as biological, chemical, acoustic, and magnetic actuations. Subsequently, we analyze the applications of these microrobots in different cancer treatment modalities, including photothermal therapy, chemotherapy, immunotherapy, and various synergistic combination therapies. Finally, we present future outlooks for the development of macrophage-based microrobots.

Nanoengineered Macrophages Armed with TLR7/8 Agonist Enhance Remodeling of Immunosuppressive Tumor Microenvironment

Although adoptive cell-based therapy is illuminated as one of the promising approaches in cancer immunotherapy, it shows low antitumor efficacy because transferred cells adapt and alter toward a pro-tumoral phenotype in response to the tumor's immunosuppressive milieu. Herein, nanoengineered macrophages anchored with functional liposome armed with cholesterol-conjugated Toll-like receptor 7/8 agonist (masked TLR7/8a, m7/8a) are generated to overcome the shortcomings of current macrophage-based therapies and enhance the remodeling of the immunosuppressive tumor microenvironment (TME). The liposome-anchored macrophages (LAMΦ-m7/8a), are fabricated by anchoring dibenzocyclooctyne-modified liposome(m7/8a) onto azido-expressing macrophages via a bio-orthogonal click reaction, are continuously invigorated due to the slow internalization of liposome(m7/8a) and sustained activation. LAMΦ-m7/8a secreted ≈3 and 33-fold more IL-6 and TNF-α than conventional M1-MΦ, maintained the M1 phenotype, and phagocytosed tumor cells for up to 48 h in vitro. Both intratumoral and intravenous injections of LAMΦ-m7/8a induced effective antitumor efficacy when treated in combination with doxorubicin-loaded liposomes in 4T1-tumor bearing mice. It not only increases the infiltration of antigen-specific CD8+ T cells secreting granzyme B, IFN-γ, and TNF-α within the TME, but also reduces myeloid-derived suppressor cells. These results suggest that LAMΦ-m7/8a may provide a suitable alternative to next-generation cell-based therapy platform.

Good CARMA: Turning bad tumor-resident myeloid cells good with chimeric antigen receptor macrophages

In religious philosophy, the concept of karma represents the effect of one's past and present actions on one's future. Macrophages are highly plastic cells with myriad roles in health and disease. In the setting of cancer, macrophages are among the most plentiful members of the immune microenvironment where they generally support tumor growth and restrain antitumor immunity. However, macrophages are not necessarily born bad. Macrophages or their immediate progenitors, monocytes, are induced to traffic to the tumor microenvironment (TME) and during this process they are polarized toward a tumor-promoting phenotype. Efforts to deplete or repolarize tumor-associated macrophages (TAM) for therapeutic benefit in cancer have to date disappointed. By contrast, genetic engineering of macrophages followed by their transit into the TME may allow these impressionable cells to mend their ways. In this review, we summarize and discuss recent advances in the genetic engineering of macrophages for the treatment of cancer.

Controllable hypoxia-activated chemotherapy as a dual enhancer for synergistic cancer photodynamic immunotherapy

The efficacy of photodynamic therapy (PDT) is severely limited by the hypoxic tumor microenvironment (TME), while the performance of PDT-aroused antitumor immunity is frustrated by the immunosuppressive TME and deficient immunogenic cell death (ICD) induction. To simultaneously tackle these pivotal problems, we herein create an albumin-based nanoplatform co-delivering IR780, NLG919 dimer and a hypoxia-activated prodrug tirapazamine (TPZ) as the dual enhancer for synergistic cancer therapy. Under NIR irradiation, IR780 generates 1O2 for PDT, which simultaneously cleaves the ROS-sensitive linker for triggered TPZ release, and activates its chemotherapy via exacerbated tumor hypoxia. Meanwhile, firstly found by us, TPZ-mediated chemotherapy boosts PDT-induced tumor ICD to evoke stronger antitumor immunity including the development of tumor-specific cytotoxic T lymphocytes (CTLs). Eventually, enriched intratumoral GSH triggers the activation of NLG919 to mitigate the immunosuppressive TME via specific indoleamine 2,3-dioxygenase 1 (IDO-1) inhibition, consequently promoting the intratumoral infiltration of CTLs and the killing of both primary and distant tumors, while the resultant memory T cells allows nearly 100% suppression of tumor recurrence and metastasis. This nanoplatform sets up an example for dully enhanced photodynamic immunotherapy of breast cancer via hypoxia-activated chemotherapy, and paves a solid way for the treatment of other hypoxic and immunosuppressive malignant tumors.

Promotion of ICD via Nanotechnology

Immunotherapy represents the most promising treatment strategy for cancer, but suffers from compromised therapeutic efficiency due to low immune activity of tumor cells and an immunosuppressive microenvironment, which significantly hampers the clinical translations of this treatment strategy. To promote immunotherapy with desired therapeutic efficiency, immunogenic cell death (ICD), a particular type of death capable of reshaping body's antitumor immune activity, has drawn considerable attention due to the potential to stimulate a potent immune response. Still, the potential of ICD effect remains unsatisfactory because of the intricate tumor microenvironment and multiple drawbacks of the used inducing agents. ICD has been thoroughly reviewed so far with a general classification of ICD as a kind of immunotherapy strategy and repeated discussion of the related mechanism. However, there are no published reviews, to the authors' knowledge, providing a systematic summarization on the enhancement of ICD via nanotechnology. For this purpose, this review first discusses the four stages of ICD according to the development mechanisms, followed by a comprehensive description on the use of nanotechnology to enhance ICD in the corresponding four stages. The challenges of ICD inducers and possible solutions are finally summarized for future ICD-based enhanced immunotherapy.

Revolutionizing cancer treatment: The power of cell-based drug delivery systems

Intravenous administration of drugs is a widely used cancer therapy approach. However, the efficacy of these drugs is often hindered by various biological barriers, including circulation, accumulation, and penetration, resulting in poor delivery to solid tumors. Recently, cell-based drug delivery platforms have emerged as promising solutions to overcome these limitations. These platforms offer several advantages, including prolonged circulation time, active targeting, controlled release, and excellent biocompatibility. Cell-based delivery systems encompass cell membrane coating, intracellular loading, and extracellular backpacking. These innovative platforms hold the potential to revolutionize cancer diagnosis, monitoring, and treatment, presenting a plethora of opportunities for the advancement and integration of pharmaceuticals, medicine, and materials science. Nevertheless, several technological, ethical, and financial barriers must be addressed to facilitate the translation of these platforms into clinical practice. In this review, we explore the emerging strategies to overcome these challenges, focusing specifically on the functions and advantages of cell-mediated drug delivery in cancer treatment.

A photo-triggered self-accelerated nanoplatform for multifunctional image-guided combination cancer immunotherapy

Precise and efficient image-guided immunotherapy holds great promise for cancer treatment. Here, we report a self-accelerated nanoplatform combining an aggregation-induced emission luminogen (AIEgen) and a hypoxia-responsive prodrug for multifunctional image-guided combination immunotherapy. The near-infrared AIEgen with methoxy substitution simultaneously possesses boosted fluorescence and photoacoustic (PA) brightness for the strong light absorption ability, as well as amplified type I and type II photodynamic therapy (PDT) properties via enhanced intersystem crossing process. By formulating the high-performance AIEgen with a hypoxia-responsive paclitaxel (PTX) prodrug into nanoparticles, and further camouflaging with macrophage cell membrane, a tumor-targeting theranostic agent is built. The integration of fluorescence and PA imaging helps to delineate tumor site sensitively, providing accurate guidance for tumor treatment. The light-induced PDT effect could consume the local oxygen and lead to severer hypoxia, accelerating the release of PTX drug. As a result, the combination of PDT and PTX chemotherapy induces immunogenic cancer cell death, which could not only elicit strong antitumor immunity to suppress the primary tumor, but also inhibit the growth of distant tumor in 4T1 tumor-bearing female mice. Here, we report a strategy to develop theranostic agents via rational molecular design for boosting antitumor immunotherapy.

Dynamic regulation of drug biodistribution by turning tumors into decoys for biomimetic nanoplatform to enhance the chemotherapeutic efficacy of breast cancer with bone metastasis

Breast cancer with bone metastasis accounts for serious cancer-associated pain which significantly reduces the quality of life of affected patients and promotes cancer progression. However, effective treatment using nanomedicine remains a formidable challenge owing to poor drug delivery efficiency to multiple cancer lesions and inappropriate management of cancer-associated pain. In this study, using engineered macrophage membrane (EMM) and drugs loaded nanoparticle, we constructed a biomimetic nanoplatform (EMM@DJHAD) for the concurrent therapy of bone metastatic breast cancer and associated pain. Tumor tropism inherited from EMM provided the targeting ability for both primary and metastatic lesions. Subsequently, the synergistic combination of decitabine and JTC801 boosted the lytic and inflammatory responses accompanied by a tumoricidal effect, which transformed the tumor into an ideal decoy for EMM, resulting in prolonged troop migration toward tumors. EMM@DJHAD exerted significant effects on tumor suppression and a pronounced analgesic effect by inhibiting µ-opioid receptors in bone metastasis mouse models. Moreover, the nanoplatform significantly reduced the severe toxicity induced by chemotherapy agents. Overall, this biomimetic nanoplatform with good biocompatibility may be used for the effective treatment of breast cancer with bone metastasis.

Theranostic chimeric antigen receptor (CAR)-T cells: Insight into recent trends and challenges in solid tumors

Cell therapy has reached significant milestones in various life-threatening diseases, including cancer. Cell therapy using fluorescent and radiolabeled chimeric antigen receptor (CAR)-T cell is a successful strategy for diagnosing or treating malignancies. Since cell therapy approaches have different results in cancers, the success of hematological cancers has yet to transfer to solid tumor therapy, leading to more casualties. Therefore, there are many areas for improvement in the cell therapy platform. Understanding the therapeutic barriers associated with solid cancers through cell tracking and molecular imaging may provide a platform for effectively delivering CAR-T cells into solid tumors. This review describes CAR-T cells' role in treating solid and non-solid tumors and recent advances. Furthermore, we discuss the main obstacles, mechanism of action, novel strategies and solutions to overcome the challenges from molecular imaging and cell tracking perspectives.

"Zombie" Macrophages for Targeted Drug Delivery to Treat Acute Pneumonia

A cell-based drug delivery system has emerged as a promising drug delivery platform. Due to their innate inflammatory tropism, natural and engineered macrophages have exhibited targeted accumulation in inflammatory tissues, which has allowed targeted delivery of medicine for the treatment of a variety of inflammatory diseases. Nevertheless, live macrophages may take up the medicine and metabolize it during preparation, storage, and in vivo delivery, sometimes causing unsatisfactory therapeutic efficacy. In addition, live macrophage-based drug delivery systems are usually freshly prepared and injected, due to the poor stability that does not allow storage. "Off-the-shelf" products would be indeed conducive to the timely therapy of acute diseases. Herein, a cryo-shocked macrophage-based drug delivery system was developed via supramolecular conjugation of cyclodextrin (CD)-modified "zombie" macrophages and adamantane (ADA)-functionalized nanomedicine. "Zombie" macrophages exhibited a much better storage stability over time than their counterpart live macrophage drug carriers and maintained cell morphology, membrane integrity, and biological functions. In an acute pneumonia mouse model, "zombie" macrophages carried quercetin-loaded nanomedicine, hand-in-hand, to the inflammatory lung tissues and effectively alleviated the inflammation in mice.

Light-responsive nanomedicine for cancer immunotherapy

Immunotherapy emerged as a paradigm shift in cancer treatments, which can effectively inhibit cancer progression by activating the immune system. Remarkable clinical outcomes have been achieved through recent advances in cancer immunotherapy, including checkpoint blockades, adoptive cellular therapy, cancer vaccine, and tumor microenvironment modulation. However, extending the application of immunotherapy in cancer patients has been limited by the low response rate and side effects such as autoimmune toxicities. With great progress being made in nanotechnology, nanomedicine has been exploited to overcome biological barriers for drug delivery. Given the spatiotemporal control, light-responsive nanomedicine is of great interest in designing precise modality for cancer immunotherapy. Herein, we summarized current research utilizing light-responsive nanoplatforms to enhance checkpoint blockade immunotherapy, facilitate targeted delivery of cancer vaccines, activate immune cell functions, and modulate tumor microenvironment. The clinical translation potential of those designs is highlighted and challenges for the next breakthrough in cancer immunotherapy are discussed.

Targeting immune checkpoints on tumor-associated macrophages in tumor immunotherapy

Unprecedented breakthroughs have been made in cancer immunotherapy in recent years. Particularly immune checkpoint inhibitors have fostered hope for patients with cancer. However, immunotherapy still exhibits certain limitations, such as a low response rate, limited efficacy in certain populations, and adverse events in certain tumors. Therefore, exploring strategies that can improve clinical response rates in patients is crucial. Tumor-associated macrophages (TAMs) are the predominant immune cells that infiltrate the tumor microenvironment and express a variety of immune checkpoints that impact immune functions. Mounting evidence indicates that immune checkpoints in TAMs are closely associated with the prognosis of patients with tumors receiving immunotherapy. This review centers on the regulatory mechanisms governing immune checkpoint expression in macrophages and strategies aimed at improving immune checkpoint therapies. Our review provides insights into potential therapeutic targets to improve the efficacy of immune checkpoint blockade and key clues to developing novel tumor immunotherapies.

CD44 and HAP-Conjugated hADSCs as Living Materials for Targeted Tumor Therapy and Bone Regeneration

Combining targeted tumor therapy with tissue regeneration represents a promising strategy for synergistic tumor therapy. In this study, a multifunctional living material is constructed with human-derived adipose stem cells (hADSCs) and antibody-modified hydroxyapatite nanorods (nHAP) for targeted drug delivery and bone regeneration following surgery. The living material delivers the therapeutics to the tumor site efficiently based on the strength of the inherent tumor tropism of hADSCs. The bioconjugation of nHAP with hADSCs via specific antibody modification is found to be biocompatible, even when loaded with the chemotherapeutic drug doxorubicin (Dox). The endocytosis of nHAP stimulates the osteogenic differentiation of hADSCs, promoting bone tissue regeneration. Moreover, the antibody-modified nHAP-hADSC conjugate exhibits targeted tumor delivery, which is further facilitated by pH-triggered release of Dox, inducing apoptosis of tumor cells with low toxicity to healthy tissues. Therefore, the present study provides a general strategy for engineering living materials to achieve targeted tumor therapy and bone tissue regeneration after surgery, which can be extended to other disease types.

Microfluidic Formulation of Curcumin-Loaded Multiresponsive Gelatin Nanoparticles for Anticancer Therapy

Current anticancer research shows that a combination of multiple treatment methods can greatly improve the killing of tumor cells. Using the latest microfluidic swirl mixer technology, combined with chemotherapy and photothermal-ablation therapy, we developed multiresponsive targeted antitumor nanoparticles (NPs) made of folate-functionalized gelatin NPs under 200 nm in size and with encapsulated CuS NPs, Fe₃O₄ NPs, and curcumin (Cur). By exploring gelatin's structure, adjusting its concentration and pH, and fine-tuning the fluid dynamics in the microfluidic device, the best preparation conditions were obtained for gelatin NPs with an average particle size of 90 ± 7 nm. The comparative targeting of the drug delivery system (DDS) was demonstrated on lung adenocarcinoma A549 cells (low level of folate receptors) and breast adenocarcinoma MCF-7 cells (high level of folate receptors). Folic acid helps achieve targeting and accurate delivery of NPs to the MCF-7 tumor cells. The synergistic photothermal ablation and curcumin's anticancer activity are achieved through infrared light irradiation (980 nm), while Fe₃O₄ is guided with an external magnetic field to target gelatin NPs and accelerate the uptake of drugs, thus efficiently killing tumor cells. The method described in this work is simple, easy to repeat, and has great potential to be scaled up for industrial production and subsequent clinical use.

Long Circulating Cancer Cell-Targeted Bionic Nanocarriers Enable Synergistic Combinatorial Therapy in Colon Cancer

Cancer nanomedicine treatment aims to achieve highly specific targeting and localization to cancer cells. Coating of nanoparticles with cell membranes endows them with homologous cellular mimicry, enabling nanoparticles to acquire new functions and properties, including homologous targeting and long circulation in vivo, and can enhance internalization by homologous cancer cells. Herein, we fused a human-derived HCT116 colon cancer cell membrane (cM) with a red blood cell membrane (rM) to fabricate an erythrocyte-cancer cell hybrid membrane (hM). Oxaliplatin and chlorin e6 (Ce6) co-encapsulated reactive oxygen species-responsive nanoparticles (NPOC) were camouflaged by hM and obtained a hybrid biomimetic nanomedicine (denoted as hNPOC) for colon cancer therapy. hNPOC exhibited prolonged circulation time and recognized homologous targeting ability in vivo since both rM and HCT116 cM proteins were maintained on the hNPOC surface. hNPOC showed enhanced homologous cell uptake in vitro and considerable homologous self-localization in vivo, producing effective synergistic chemophotodynamic therapy efficacy under irradiation with a homologous HCT116 tumor compared to that with a heterologous tumor. Together, the biomimetic hNPOC nanoparticles showed prolonged blood circulation and preferential cancer cell-targeted function in vivo to provide a bioinspired strategy for chemophotodynamic synergistic therapy of colon cancer.

Bone/cartilage targeted hydrogel: Strategies and applications

The skeletal system is responsible for weight-bearing, organ protection, and movement. Bone diseases caused by trauma, infection, and aging can seriously affect a patient's quality of life. Bone targeted biomaterials are suitable for the treatment of bone diseases. Biomaterials with bone-targeted properties can improve drug utilization and reduce side effects. A large number of bone-targeted micro-nano materials have been developed. However, only a few studies addressed bone-targeted hydrogel. The large size of hydrogel makes it difficult to achieve systematic targeting. However, local targeted hydrogel still has significant prospects. Molecules in bone/cartilage extracellular matrix and bone cells provide binding sites for bone-targeted hydrogel. Drug delivery systems featuring microgels with targeting properties is a key construction strategy for bone-targeted hydrogel. Besides, injectable hydrogel drug depot carrying bone-targeted drugs is another strategy. In this review, we summarize the bone-targeted hydrogel through application environment, construction strategies and disease applications. We hope this article will provide a reference for the development of bone-targeted hydrogels. We also hope this article could increase awareness of bone-targeted materials.

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Introducing the microenvironment and target molecules in different parts of long bones.

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Summarizing the construction strategy of micro/nanoparticle hydrogel with bone targeting properties.

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Summarizing the construction strategy of hydrogel based depot carrying bone-targeted drugs.

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Reporting the application and effect of bone targeting hydrogel in common bone diseases.