M2 macrophage microvesicle-inspired nanovehicles improve accessibility to cancer cells and cancer stem cells in tumors

Synergistic Therapy of Metastatic Breast Cancers by Biomimetic Chemotherapeutic Drug-Gene Nanoparticles

Cancer metastasis is responsible for more than 90% of tumor-related deaths. Especially, metastatic breast cancer (MBC) is a common malignancy with a high mortality among women worldwide. It is urgent to develop effective drugs for the treatment of MBC. Herein, biomimetic chemotherapeutic drug-gene nanoparticles (named TPT-ASOVEGF@MM NPs) were constructed for the combination therapy of MBC. First, topotecan hydrochloride (TPT) and vascular endothelial growth factor antisense oligonucleotide (ASOVEGF) were coself-assembled in water through electrostatic interaction to produce chemotherapeutic drug-gene nanoparticles (TPT-ASOVEGF NPs). Then, the nanoparticles were encapsulated within macrophage membranes (MM) to form biomimetic TPT-ASOVEGF@MM NPs with long circulation time in blood and active tumor-targeting ability. TPT-ASOVEGF@MM NPs can be effectively internalized by breast cancer cells and then the nanoparticles collapse to simultaneously release TPT and ASOVEGF. ASOVEGF can inhibit the expression of VEGF, impeding the process of neovascularization and blocking the metastatic pathway of cancer cells. Meanwhile, TPT can bind to the topoisomerase I-DNA complex to prevent DNA repair and replication, and further induce apoptosis of cancer cells. In addition, TPT can also affect hypoxia-inducible factor 1α (HIF-1α) expression and inhibit hypoxia-induced tumor metastasis to achieve synergistic therapy with ASOVEGF. In MBC mouse models, the in vivo inhibition rate of TPT-ASOVEGF@MM NPs for lung metastasis was 89.5%, with minor toxic side effects and the least number of metastatic nodules in the lungs. In summary, TPT-ASOVEGF@MM NPs would be a promising biomimetic nanodrug for chemo-gene combination therapy of MBC with high efficacy and safety in clinics.

Nanotherapeutics for Macrophage Network Modulation in Tumor Microenvironments: Targets and Tools

Macrophage is an important component in the tumor immune microenvironment, which exerts significant influence on tumor development and metastasis. Due to their dual nature of promoting and suppressing inflammation, macrophages can serve as both targets for tumor immunotherapy and tools for treating malignancies. However, the abundant infiltration of tumor-associated macrophages dominated by an immunosuppressive phenotype maintains a pro-tumor microenvironment, and engineering macrophages using nanotechnology to manipulate the tumor immune microenvironment represent a feasible approach for cancer immunotherapy. Additionally, considering the phagocytic and specifically tumor-targeting capabilities of M1 macrophages, macrophages manipulated through cellular engineering and nanotechnology, as well as macrophage-derived exosomes and macrophage membranes, can also become effective tools for cancer treatment. In conclusion, nanotherapeutics targeting macrophages remains immense potential for the development of macrophage-mediated tumor treatment methods and will further enhance our understanding, diagnosis, and treatment of various malignants.

Innovative utilization of cell membrane-coated nanoparticles in precision cancer therapy

Cell membrane-coated nanoparticles (CMNPs) have recently emerged as a promising platform for cancer therapy. By encapsulating therapeutic agents within a cell membrane-derived coating, these nanoparticles combine the advantages of synthetic nanoparticles and natural cell membranes. This review provides a comprehensive overview of the recent advancements in utilizing CMNPs as effective drug delivery vehicles for cancer therapy. The synthesis and fabrication methods of CMNPs are comprehensively discussed. Various techniques, such as extrusion, sonication, and self-assembly, are employed to coat synthetic nanoparticles with cell membranes derived from different cell types. The cell membrane coating enables biocompatibility, reducing the risk of an immune response and enhancing the stability of the nanoparticles in the bloodstream. Moreover, functionalization strategies for CMNPs, primarily chemical modification, genetic engineering, and external stimuli, are highlighted. The presence of specific cell surface markers on the coated membrane allows targeted drug delivery to cancer cells and maximizes therapeutic efficacy. Preclinical studies utilizing CMNPs for cancer therapy demonstrated the successful delivery of various therapeutic agents, such as chemotherapeutic drugs, nucleic acids, and immunotherapeutic agents, using CMNPs. Furthermore, the article explores the future directions and challenges of this technology while offering insights into its clinical potential.

Membrane-camouflaged biomimetic nanoplatform with arsenic complex for synergistic reinforcement of liver cancer therapy

Aim: Arsenic has excellent anti-advanced liver cancer effects through a variety of pathways, but its severe systemic toxicity forces the need for a safe and effective delivery strategy.Methods: Based on the chelating metal ion properties of polydopamine (PDA), arsenic was immobilized on an organic carrier, and a M1-like macrophage cell membrane (MM)-camouflaged manganese-arsenic complex mesoporous polydopamine (MnAsOx@MP@M) nanoplatform was successfully constructed. MnAsOx@MP@M was evaluated at the cellular level for tumor inhibition and tumor localization, and in vivo for its anti-liver cancer effect in a Hepa1-6 tumor-bearing mouse model.Results: The nanoplatform targeted the tumor site through the natural homing property of MM, completely degraded and released drugs to kill tumor cells in an acidic environment, while playing an immunomodulatory role in promoting tumor-associated macrophages (TAMs) repolarization.Conclusion: MnAsOx@MP@M has synergistically enhanced the targeted therapeutics against liver cancer via nanotechnology and immunotherapy, and it is expected to become a safe and multifunctional treatment platform in clinical oncology.

Genetically engineered nanomodulators elicit potent immunity against cancer stem cells by checkpoint blockade and hypoxia relief

Rapid development of checkpoint inhibitors has provided significant breakthroughs for cancer stem cell (CSC) therapy, while the therapeutic efficacy is restricted by hypoxia-mediated tumor immune evasion, especially hypoxia-induced CD47 overexpression in CSCs. Herein, we developed a genetically engineered CSC membrane-coated hollow manganese dioxide (hMnO2@gCMs) to elicit robust antitumor immunity by blocking CD47 and alleviating hypoxia to ultimately achieve the eradication of CSCs. The hMnO2 core effectively alleviated tumor hypoxia by inducing decomposition of tumor endogenous H2O2, thus suppressing the CSCs and reducing the expression of CD47. Cooperating with hypoxia relief-induced downregulation of CD47, the overexpressed SIRPα on gCM shell efficiently blocked the CD47-SIRPα "don't eat me" pathway, synergistically eliciting robust antitumor-mediated immune responses. In a B16F10-CSC bearing melanoma mouse model, the hMnO2@gCMs showed an enhanced therapeutic effect in eradicating CSCs and inhibiting tumor growth. Our work presents a simple, safe, and robust platform for CSC eradication and cancer immunotherapy.

Stemness subtypes in lower-grade glioma with prognostic biomarkers, tumor microenvironment, and treatment response

Our research endeavors are directed towards unraveling the stem cell characteristics of lower-grade glioma patients, with the ultimate goal of formulating personalized treatment strategies. We computed enrichment stemness scores and performed consensus clustering to categorize phenotypes. Subsequently, we constructed a prognostic risk model using weighted gene correlation network analysis (WGCNA), random survival forest regression analysis as well as full subset regression analysis. To validate the expression differences of key genes, we employed experimental methods such as quantitative Polymerase Chain Reaction (qPCR) and assessed cell line proliferation, migration, and invasion. Three subtypes were assigned to patients diagnosed with LGG. Notably, Cluster 2 (C2), exhibiting the poorest survival outcomes, manifested characteristics indicative of the subtype characterized by immunosuppression. This was marked by elevated levels of M1 macrophages, activated mast cells, along with higher immune and stromal scores. Four hub genes-CDCA8, ORC1, DLGAP5, and SMC4-were identified and validated through cell experiments and qPCR. Subsequently, these validated genes were utilized to construct a stemness risk signature. Which revealed that Lower-Grade Glioma (LGG) patients with lower scores were more inclined to demonstrate favorable responses to immune therapy. Our study illuminates the stemness characteristics of gliomas, which lays the foundation for developing therapeutic approaches targeting CSCs and enhancing the efficacy of current immunotherapies. By identifying the stemness subtype and its correlation with prognosis and TME patterns in glioma patients, we aim to advance the development of personalized treatments, enhancing the ability to predict and improve overall patient prognosis.

Recent Advances in the Development of Membrane-derived Vesicles for Cancer Immunotherapy

The surface proteins on cell membranes enable the cells to have different properties, such as high biocompatibility, surface modifiability, and homologous targeting ability. Cell-membrane-derived vesicles have features identical to those of their parental cells, which makes them one of the most promising materials for drug delivery. Recently, as a result of the impressive effects of immunotherapy in cancer treatment, an increasing number of researchers have used cell-membrane-derived vesicles to enhance immune responses. To be more specific, the membrane vesicles derived from immune cells, tumor cells, bacteria, or engineered cells have the antigen presentation capacity and can trigger strong anti-tumor effects of the immune system. In this review, we first indicated a brief description of the vesicles and then introduced the detection technology and drug-loading methods for them. Secondly, we concluded the characteristics and applications of vesicles derived from different sources in cancer immunotherapy.

Influence of unsaturated fatty acids on the antitumor activity of polymeric conjugates grafted with cabazitaxel against prostate cancer

Cabazitaxel (CTX) is a medication used for treating metastatic prostate cancer. However, its effectiveness is majorly limited by its poor water solubility and lack of tumor targeting. In this study, three unsaturated fatty acids, GLA, ALA and DHA, were separately connected with CTX and then covalently attached to bifunctionalized dextran through a linker to produce three dual drug conjugates named dextran-GLA-CTX, dextran-ALA-CTX and dextran-DHA-CTX. The three conjugates displayed enhanced solubility of CTX in water and improved antitumor effects compared to the conventional CTX formulation. The results also confirmed that dextran-GLA-CTX exhibited the strongest antitumor activity, while dextran-DHA-CTX displayed less efficacy, as evaluated through xenografted nude mice bearing PC-3 and DU145 prostate cancer cells. Additionally, dextran-GLA-CTX showed greater inhibition of tumor growth than dextran-CTX. Moreover, the dextran-GLA-CTX conjugate was found to prolong the half-life of CTX in plasma and selectively accumulate in tumors. This study revealed that unsaturated fatty acids can enhance the antitumor activity of dextran-based conjugates grafted with CTX.

Sniping Cancer Stem Cells with Nanomaterials

Cancer stem cells (CSCs) drive tumor initiation, progression, and therapeutic resistance due to their self-renewal and differentiation capabilities. Despite encouraging progress in cancer treatment, conventional approaches often fail to eliminate CSCs, necessitating the development of precise targeted strategies. Recent advances in materials science and nanotechnology have enabled promising CSC-targeted approaches, harnessing the power of tailoring nanomaterials in diverse therapeutic applications. This review provides an update on the current landscape of nanobased precision targeting approaches against CSCs. We elucidate the nuanced application of organic, inorganic, and bioinspired nanomaterials across a spectrum of therapeutic paradigms, encompassing targeted therapy, immunotherapy, and multimodal synergistic therapies. By examining the accomplishments and challenges in this potential field, we aim to inform future efforts to advance nanomaterial-based therapies toward more effective "sniping" of CSCs and tumor clearance.

What should be the future direction of development in the field of prostate cancer with lung metastasis?

BACKGROUND

Since the start of the 21st century, prostate cancer with lung metastasis (PCLM) has accumulated significant scientific research output. However, a systematic knowledge framework for PCLM is still lacking.

AIM

To reconstruct the global knowledge system in the field of PCLM, sort out hot research directions, and provide reference for the clinical and mechanism research of PCLM.

METHODS

We retrieved 280 high-quality papers from the Web of Science Core Collection and conducted a bibliometric analysis of keywords, publication volume, and citation frequency. Additionally, we selected differentially expressed genes from global high-throughput datasets and performed enrichment analysis and protein-protein interaction analysis to further summarize and explore the mechanisms of PCLM.

RESULTS

PCLM has received extensive attention over the past 22 years, but there is an uneven spatial distribution in PCLM research. In the clinical aspect, the treatment of PCLM is mainly based on chemotherapy and immunotherapy, while diagnosis relies on methods such as prostate-specific membrane antigen positron emission tomography/computed tomography. In the basic research aspect, the focus is on cell adhesion molecules and signal transducer and activator of transcription 3, among others. Traditional treatments, such as chemotherapy, remain the mainstay of PCLM treatment, while novel approaches such as immunotherapy have limited effectiveness in PCLM. This study reveals for the first time that pathways related to coronavirus disease 2019, cytokine-cytokine receptor interaction, and ribosome are closely associated with PCLM.

CONCLUSION

Future research should focus on exploring and enhancing mechanisms such as cytokine-cytokine receptor interaction and ribosome and improve existing mechanisms like cadherin binding and cell adhesion molecules.

The Roles of Extracellular Vesicles in the Progression of Renal Cell Carcinoma and Their Potential for Future Clinical Application

Renal cell carcinoma (RCC) is the most common type of kidney cancer and is thought to originate from renal tubular epithelial cells. Extracellular vesicles (EVs) are nanosized lipid bilayer vesicles that are secreted into extracellular spaces by nearly all cell types, including cancer cells and non-cancerous cells. EVs are involved in multiple steps of RCC progression, such as local invasion, host immune modulation, drug resistance, and metastasis. Therefore, EVs secreted from RCC are attracting rapidly increasing attention from researchers. In this review, we highlight the mechanism by which RCC-derived EVs lead to disease progression as well as the potential and challenges related to the clinical implications of EV-based diagnostics and therapeutics.

A type I AIE photosensitiser-loaded biomimetic nanosystem allowing precise depletion of cancer stem cells and prevention of cancer recurrence after radiotherapy

Radioresistance of Cancer stem cell (CSC) is an important cause of tumor recurrence after radiotherapy (RT). Herein, we designed a type I aggregation-induced emission (AIE) photosensitiser-loaded biomimetic mesoporous organosilicon nanosystem (PMT) for precise depletion of CSC to prevent tumor recurrence after RT. This PMT system is composed of a type I AIE photosensitiser (TBP-2) loaded mesoporous organosilicon nanoparticles (MON) with an outer platelet membrane. The PMT system is able to specifically target CSC. Intracellular glutathione activity leads to MON degradation and the release of TBP-2. Type I photodynamic therapy is activated by exposure to white light, producing a large amount of hydroxyl radicals to promote CSC death. The results of in vivo experiments demonstrated specific removal of CSC following PMT treatment, with no tumor recurrence observed when combined with RT. However, tumor recurrence was observed in mice that received RT only. The expression of CSC markers was significantly reduced following PMT treatment. We demonstrate the development of a system for the precise removal of CSC with good biosafety and high potential for clinical translation. We believe the PMT nanosystem represents a novel idea in the prevention of tumor recurrence.

Spatial-Drug-Laden Protease-Activatable M1 Macrophage System Targets Lung Metastasis and Potentiates Antitumor Immunity

Lung metastasis is a critical cause of cancer mortality and its therapy is largely challenged by the limited drug delivery efficiency and robust immunosuppression in metastatic tumors. Herein, we designed a spatial-drug-laden M1 macrophage system with liposomal R848 inside and fibroblast activation protein protease (FAP)-sensitive phospholipid-DM4 conjugate on the membrane of M1 macrophage (RDM). RDM could preferentially accumulate at the metastatic lesions in lungs and responsively release the therapeutic agents as free drug molecules or drug-loaded nanovesicles. RDM treatment notably enhanced the infiltration of CD3⁺CD8⁺ T cells to lung metastasis and, respectively, caused an 8.54-, 12.87- and 2.85-fold improvement of the granzyme-B-, interferon-γ-, and Ki67-positive subtypes versus negative control. Moreover, RDM treatment produced a 90.99% inhibition of lung metastasis in 4T1 models and significant prolongation of survival in three murine lung metastatic models. Therefore, the drug-laden FAP-sensitive M1 macrophage system represents a feasible strategy to target lung metastasis and boost antitumor immunity for antimetastasis therapy.

A Meta-analysis on the Effectiveness of Extracellular Vesicles as Nanosystems for Targeted Delivery of Anticancer Drugs

While the efficacy of anticancer drugs is hampered by low bioavailability and systemic toxicity, the uncertainty remains whether encapsulation of these drugs into natural nanovesicles such as extracellular vesicles (EVs) could improve controlled drug release and efficacy for targeted tumor therapy. Thus, we performed a meta-analysis for studies reporting the efficacy of EVs as nanosystems to deliver drugs and nucleic acid, protein, and virus (NPV) to tumors using the random-effects model. The electronic search of articles was conducted through Cochrane, PubMed, Scopus, Science Direct, and Clinical Trials Registry from inception up till September 2022. The pooled summary estimate and 95% confidence interval of tumor growth inhibition, survival, and tumor targeting were obtained to assess the efficacy. The search yielded a total of 119 studies that met the inclusion criteria having only 1 clinical study. It was observed that the drug-loaded EV was more efficacious than the free drug in reducing tumor volume and weight with the standardized mean difference (SMD) of -1.99 (95% CI: -2.36, -1.63; p < 0.00001) and -2.12 (95% CI: -2.48, -1.77; p < 0.00001). Similarly, the mean estimate of tumor volume and weight for NPV were the following: SMD: -2.30, 95% CI: -3.03, -1.58; p < 0.00001 and SMD: -2.05, 95% CI: -2.79, -1.30; p < 0.00001. Treatment of tumors with EV-loaded anticancer agents also prolonged survival (HR: 0.15, 95% CI: 0.10, 0.22, p < 0.00001). Furthermore, EVs significantly delivered drugs to tumors as revealed by the higher concentration at the tumor site (SMD: -2.73, 95% CI: -3.77, -1.69; p < 0.00001). This meta-analysis revealed that EV-loaded drugs and NPV performed significantly better in tumor growth inhibition with improved survival than the free anticancer agents, suggesting EVs as safe nanoplatforms for targeted tumor therapy.

Macrophage Membrane-Coated Nano-Gemcitabine Promotes Lymphocyte Infiltration and Synergizes AntiPD-L1 to Restore the Tumoricidal Function

The limited lymphocyte infiltration and exhaustion of tumoricidal functions in solid tumors remain a formidable obstacle to cancer immunotherapy. Herein, we designed a macrophage membrane-coated nano-gemcitabine system (MNGs) to promote lymphocyte infiltration and then synergized anti-programmed death ligand 1 (antiPD-L1) to reinvigorate the exhausted lymphocytes. MNGs exhibited effective intratumor-permeating and responsive drug-releasing capacity, produced notable elimination of versatile immunosuppressive cells, and promoted lymphocyte infiltration into cancer cell regions in tumors, but over 50% of these infiltrated lymphocytes were in the exhausted state. Compared with MNG monotherapy, the MNGs+antiPD-L1 combination produced 31.77% and 30.63% reduction of exhausted CD3⁺CD8⁺ T cells and natural killer (NK) cells and 2.83- and 3.17-fold increases of interferon-γ (IFN-γ)-positive subtypes, respectively, thereby resulting in considerable therapeutic benefits in several tumor models. Thus, MNGs provide an encouraging strategy to promote lymphocyte infiltration and synergize antiPD-L1 to restore their tumoricidal function for cancer immunotherapy.

Bioinspired nanovehicle of furoxans-oxaliplatin improves tumoral distribution for chemo-radiotherapy

The spatiotemporal distribution of therapeutic agents in tumors remains an essential challenge of radiation-mediated therapy. Herein, we rationally designed a macrophage microvesicle-inspired nanovehicle of nitric oxide donor-oxaliplatin (FO) conjugate (M-PFO), aiming to promote intratumor permeation and distribution profiles for chemo-radiotherapy. FO was responsively released from M-PFO in intracellular acidic environments, and then be activated by glutathione (GSH) into active oxaliplatin and NO molecules in a programmed manner. M-PFO exhibited notable accumulation, permeation and cancer cell accessibility in tumor tissues. Upon radiation, the reactive peroxynitrite species (ONOO^-) were largely produced, which could diffuse into regions over 400 μm away from the tumor vessels and be detectable after 24 h of radiation, thereby exhibiting superior efficacy in improving the spatiotemporal distribution in tumors versus common reactive oxygen species (ROS). Moreover, M-PFO mediated chemo-radiotherapy caused notable inhibition of tumor growth, with an 89.45% inhibition in HT-29 tumor models and a 92.69% suppression in CT-26 tumor models. Therefore, this bioinspired design provides an encouraging platform to improve intratumor spatiotemporal distribution to synergize chemo-radiotherapy.

Metabolism in Cancer Stem Cells: Targets for Clinical Treatment

Cancer stem cells (CSCs) have high tumorigenicity, high metastasis and high resistance to treatment. They are the key factors for the growth, metastasis and drug resistance of malignant tumors, and are also the important reason for the occurrence and recurrence of tumors. Metabolic reprogramming refers to the metabolic changes that occur when tumor cells provide sufficient energy and nutrients for themselves. Metabolic reprogramming plays an important role in regulating the growth and activity of cancer cells and cancer stem cells. In addition, the immune cells or stromal cells in the tumor microenvironment (TME) will change due to the metabolic reprogramming of cancer cells. Summarizing the characteristics and molecular mechanisms of metabolic reprogramming of cancer stem cells will provide new ideas for the comprehensive treatment of malignant tumors. In this review, we summarized the changes of the main metabolic pathways in cancer cells and cancer stem cells.

Macrophage Cell Membrane-Cloaked Nanoplatforms for Biomedical Applications

Biomimetic approaches utilize natural cell membrane-derived nanovesicles to camouflage nanoparticles to circumvent some limitations of nanoscale materials. This emergent cell membrane-coating technology is inspired by naturally occurring intercellular interactions, to efficiently guide nanostructures to the desired locations, thereby increasing both therapeutic efficacy and safety. In addition, the intrinsic biocompatibility of cell membranes allows the crossing of biological barriers and avoids elimination by the immune system. This results in enhanced blood circulation time and lower toxicity in vivo. Macrophages are the major phagocytic cells of the innate immune system. They are equipped with a complex repertoire of surface receptors, enabling them to respond to biological signals, and to exhibit a natural tropism to inflammatory sites and tumorous tissues. Macrophage cell membrane-functionalized nanosystems are designed to combine the advantages of both macrophages and nanomaterials, improving the ability of those nanosystems to reach target sites. Recent studies have demonstrated the potential of these biomimetic nanosystems for targeted delivery of drugs and imaging agents to tumors, inflammatory, and infected sites. The present review covers the preparation and biomedical applications of macrophage cell membrane-coated nanosystems. Challenges and future perspectives in the development of these membrane-coated nanosystems are addressed.

Macrophages Are a Double-Edged Sword: Molecular Crosstalk between Tumor-Associated Macrophages and Cancer Stem Cells

Cancer stem cells (CSCs) are a subset of highly tumorigenic cells in tumors. They have enhanced self-renewal properties, are usually chemo-radioresistant, and can promote tumor recurrence and metastasis. They can recruit macrophages into the tumor microenvironment and differentiate them into tumor-associated macrophages (TAMs). TAMs maintain CSC stemness and construct niches that are favorable for CSC survival. However, how CSCs and TAMs interact is not completely understood. An understanding on these mechanisms can provide additional targeting strategies for eliminating CSCs. In this review, we comprehensively summarize the reported mechanisms of crosstalk between CSCs and TAMs and update the related signaling pathways involved in tumor progression. In addition, we discuss potential therapies targeting CSC–TAM interaction, including targeting macrophage recruitment and polarization by CSCs and inhibiting the TAM-induced promotion of CSC stemness. This review also provides the perspective on the major challenge for developing potential therapeutic strategies to overcome CSC-TAM crosstalk.

Strategies of engineering nanomedicines for tumor retention

The retention of therapeutic agents in solid tumors at sufficient concentration and duration is crucial for their antitumor effects. Given the important contribution of nanomedicines to oncology, we herein summarized two major strategies of nanomedicines for tumor retention, such as transformation- and interactions-mediated strategies. The transformation-mediated retention strategy was achieved by enlarging particle size of nanomedicines or modulating the morphology into fibrous structures, while the interactions-mediated retention strategy was accomplished by modulating nanomedicines to promote their interactions with versatile cells or components in tumors. Moreover, we provide some considerations and perspectives of tumor-retaining nanomedicines for effective cancer therapy.