Curvature-sensing peptide inhibits tumour-derived exosomes for enhanced cancer immunotherapy

Bioresponsive nanoreactor initiates cascade reactions for tumor vascular normalization and lactate depletion to augment immunotherapy

Immune checkpoint blockade (ICB) therapy has revolutionized cancer treatment. However, abnormal tumor vasculature and excess lactate contribute to tumor immunosuppression and confer resistance to ICB therapy, seriously limiting its clinical application. Here, we have developed a bioresponsive nanoreactor, ALMn, which consists of hollow manganese dioxide nanoparticles with encapsulation of lactate oxidase and L-Arginine, to overcome immunosuppression and sensitize ICB therapy. In the tumor microenvironment, lactate oxidase catalyzes lactate to produce hydrogen peroxide, which subsequently oxidizes L-Arginine to generate nitric oxide for vascular normalization. Through cascade reactions, ALMn effectively depletes excess lactate and normalize tumor vasculature, reshaping the immunosuppressive phenotype to an immune-activated one. Transcriptomics and immunological analyses prove that ALMn facilitates the infiltration and activation of effector cells, further potentiating antitumor immunity. Consequently, ALMn sensitizes anti-PD-L1 therapy, significantly suppressing tumor growth with an 83.7 % suppression, and prolonging the survival of mice, with the median survival time increasing from 29.5 days to 54.5 days. Our study demonstrates that ALMn effectively alleviates tumor immunosuppression and synergizes with anti-PD-L1, which shows promise in boosting ICB therapy.

Enhancing immunogenicity and release of in situ-generated tumor vesicles for autologous vaccines

In situ vaccination (ISV) strategies offer an innovative approach to cancer immunotherapy by utilizing drug combinations directly at tumor sites to elicit personalized immune responses. Tumor cell-derived extracellular vesicles (TEVs) in ISV have great potential but face challenges such as low release rates and immunosuppressive proteins like programmed death ligand 1 (PD-L1) and CD47. This study develops a nanoparticle-based ISV strategy (Combo-NPs@shGNE) that enhances TEV release and modulates cargo composition. This approach combines Andrographolide, Icariside II, and shRNA targeting UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE), which accumulates in the tumor region, resulting in the regulation of immunosuppressive pathways and the reduction of sialic acid production. Decreasing the level of sialylation on the membrane through necroptosis and inhibition of sialic acid synthesis decreased the loading of PD-L1 and CD47 on vesicles, while increasing the loading of heat shock protein 70 and high mobility group box 1 on vesicles, and induced the release of highly immunogenic TEVs from the cancer cells, with a 56.44 % release, 9.57 times higher than that of blank nanoparticle-treated cells. In vivo studies demonstrate that Combo-NPs@shGNE enhances TEV yield, tumor growth, reduces metastases, and improves survival in an osteosarcoma mouse model. It promotes dendritic cell maturation, increases CD4+ and CD8+ T cell infiltration, and alters the microenvironment by reducing myeloid-derived suppressor cells and enhancing immunostimulatory factors. Additionally, it transitions tumor-associated macrophages from M2 to an M1 phenotype, thereby augmenting tumor immunity. Overall, Combo-NPs@shGNE offers a promising method for transforming tumors into personalized autologous vaccines, potentially advancing cancer treatment strategies.

Progress of extracellular vesicles-based system for tumor therapy

The increasing number of new cancer cases and cancer-related deaths worldwide highlights the urgent need to develop novel anti-tumor treatment methods to alleviate the current challenging situation. Nearly all organisms are capable of secreting extracellular vesicles (EVs), and these nano-scale EVs carrying biological molecules play an important role in intercellular communication, further affecting various physiological and pathological processes. Notably, EVs from different sources have differences in their characteristics and functions. Consequently, diverse EVs have been utilized as drug or vaccine delivery carriers for improving anti-tumor treatment due to their good safety, ease of modification and unique properties, and achieved satisfactory results. Meanwhile, the clinical trials of EV-based platform for tumor therapy are also continuously being conducted. Therefore, in this review, we summarize the recent research progress of EV-based tumor treatment methods, including the introduction of main sources and unique functions of EVs, the application of EVs in tumor treatment as well as their prospects and challenges. Additionally, considering the unique advantages of artificial EVs over natural EVs, we also highlighted their characteristics and applications in tumor treatments. We believe that this review will help researchers develop novel EV-based anti-tumor platforms through a bottom-up design and accelerate the development in this field.

Harnessing engineered extracellular vesicles for enhanced therapeutic efficacy: advancements in cancer immunotherapy

Extracellular vesicles (EVs), particularly engineered variants, have emerged as promising tools in cancer immunotherapy due to their inherent ability to modulate immune responses and deliver therapeutic agents with high specificity and minimal toxicity. These nanometer-sized vesicles, which include exosomes (Exos) and other subtypes, naturally participate in intercellular communication and are capable of carrying a diverse range of bioactive molecules, including proteins, lipids, RNAs, and metabolites. Recent advancements in the biogenesis of engineered EVs, such as strategies to modify their surface characteristics and cargo, have significantly expanded their potential as effective vehicles for targeted cancer therapies. Tailoring the contents of EVs, such as incorporating immunomodulatory molecules or gene-editing tools (GETs), has shown promising outcomes in enhancing anti-tumor immunity and overcoming the immunosuppressive tumor microenvironment (TME). Moreover, optimizing delivery mechanisms, through both passive and active targeting strategies, is crucial for improving the clinical efficacy of EV-based therapies. This review provides an overview of recent developments in the engineering of EVs for cancer immunotherapy, focusing on their biogenesis, methods of content customization, and innovations in cargo delivery. Additionally, the review addresses the challenges associated with the clinical translation of EV-based therapies, such as issues related to scalability, safety, and targeted delivery. By offering insights into the current state of the field and identifying key areas for future research, this review aims to advance the application of engineered EVs in cancer treatment.

Rational design of peptides to overcome drug resistance by metabolic regulation

Chemotherapy is widely used clinically, however, its efficacy is often compromised by the development of drug resistance, which arises from prolonged administration of drugs or other stimuli. One of the driven causes of drug resistance in tumors or bacterial infections is metabolic reprogramming, which alters mitochondrial metabolism, disrupts metabolic pathways and causes ion imbalance. Bioactive peptide materials, due to their biocompatibility, diverse bioactivities, customizable sequences, and ease of modification, have shown promise in overcoming drug resistance. This review provides an in-depth analysis of metabolic reprogramming and associated microenvironmental changes that contribute to drug resistance in common tumors and bacterial infections, suggesting potential therapeutic targets. Additionally, we explore peptide-based materials for regulating metabolism and their potential synergic effect with other therapies, highlighting the mechanisms by which these peptides reverse drug resistance. Finally, we discuss future perspectives and the clinical challenges in peptide-based treatments, aiming to offer insights for overcoming drug-resistant diseases.

Emerging Nanoparticle-Based Diagnostics and Therapeutics for Cancer: Innovations and Challenges

Malignant growth is expected to surpass other significant causes of death as one of the top reasons for dismalness and mortality worldwide. According to a World Health Organization (WHO) study, this illness causes approximately between 9 and 10 million instances of deaths annually. Chemotherapy, radiation, and surgery are the three main methods of treating cancer. These methods seek to completely eradicate all cancer cells while having the fewest possible unintended impacts on healthy cell types. Owing to the lack of target selectivity, the majority of medications have substantial side effects. On the other hand, nanomaterials have transformed the identification, diagnosis, and management of cancer. Nanostructures with biomimetic properties have been grown as of late, fully intent on observing and treating the sickness. These nanostructures are expected to be consumed by growth in areas with profound disease. Furthermore, because of their extraordinary physicochemical properties, which incorporate nanoscale aspects, a more prominent surface region, explicit geometrical features, and the ability to embody different substances within or on their outside surfaces, nanostructures are remarkable nano-vehicles for conveying restorative specialists to their designated regions. This review discusses recent developments in nanostructured materials such as graphene, dendrimers, cell-penetrating peptide nanoparticles, nanoliposomes, lipid nanoparticles, magnetic nanoparticles, and nano-omics in the diagnosis and management of cancer.

Engineering therapeutical extracellular vesicles for clinical translation

Cell-based therapies are revolutionizing medicine by replacing or modifying dysfunctional cells with healthy cells or engineered derivatives, offering disease reversal and cure. One promising approach is using cell-derived extracellular vesicles (EVs), which offer therapeutic benefits similar to cell transplants without the biosafety risks. Although EV applications face challenges like limited production, inadequate therapeutic loading, and poor targeting efficiency, recent advances in bioengineering have enhanced their effectiveness. Herein, we summarize technological breakthroughs in EV bioengineering over the past 5 years, highlighting their improved therapeutic functionalities and potential clinical prospects. We also discuss biomanufacturing processes, regulation, and safety considerations for bioengineered EV therapies, emphasizing the significance of establishing robust frameworks to ensure translation capability, safety, and therapeutic effectiveness for successful clinical adoption.

An investigation of the effect of the protein corona on the cellular uptake of nanoliposomes under flow conditions using quartz crystal microgravimetry with dissipation

When nanoparticle delivery systems are immersed in biological fluids, a complex assembly of proteins forms on their surface, creating a protein corona. The protein corona alters the physicochemical properties, toxicity, biodistribution, cellular uptake, and immune response of the nanoparticles, and consequently, their therapeutic efficacy. Currently, there is a lack of in vitro methods to assess the effects of the protein corona on nanoparticle uptake under dynamic flow and assess their binding kinetics in real-time. Here, we introduce quartz crystal microbalance with dissipation (QCM-D) as an in vitro technique, capable of incorporating dynamic flow, to study the effect of the protein corona on the binding of nanoliposome (NLP) formulations to cell surfaces as a first step in their cellular uptake. The interactions of four NLP formulations (low PEGylated, high PEGylated, negatively charged and positively charged NLPs) with A375 melanoma and THP1 cell lines were assessed by QCM-D, before and after the formation of a protein corona. Through real-time recording of the frequency and dissipation shifts (Δf and ΔD, respectively), the QCM-D results provided strong evidence of the role of the protein corona in the cellular interaction of these NLP formulations, with a variation in their adsorption kinetics depending on their initial composition. NLP's attachment to the cell surface was the lowest for PEGylated NLPs (<5%), while the positively charged NLPs showed the highest cellular attachment (≈100%), regardless of the presence of the protein corona or cell type. The effect of the protein corona was more pronounced for the negatively charged NLPs, where a significant reduction in the NLP attachment was observed. To complement the QCM-D data on the NLP attachment and to determine whether the NLP attachment leads to cellular uptake, confocal microscopy and flow cytometry were used to confirm NLP uptake by A375 and THP1 cells. Proteomic analysis revealed a differential composition of the protein corona on the various NLPs with possible implications for their sequestration and cellular uptake. Collectively, the findings suggest that QCM-D can be an important tool to study the binding of NLP formulations or other nanoparticles with cell membranes under dynamic flow, which very often differs from nanoparticle uptake under static conditions.

Therapeutically Harnessing Tumor Cell-Derived Extracellular Vesicles for Multiple Myeloma: Recent Advances and Future Perspectives

Extracellular vesicles (EVs) have emerged as pivotal regulators for extensive intercellular crosstalk owing to capsuled diverse bioactive substances such as proteins, nucleic acids, and lipids. Recent studies have shown that tumor-derived EVs significantly influence the bone marrow microenvironment, contributing to the progression of multiple myeloma (MM). This highlights the robust potential of EVs as a promising avenue for developing more effective and precise diagnostic and therapeutic strategies for MM. In this review, we briefly discuss the multifaceted roles of EVs in MM progression, as well as the diagnostic and therapeutic value in MM management. Specifically, we focus on the latest research progress regarding the therapeutic potential of EVs for MM, particularly tumor cell-derived EVs, as we elaborate on three main aspects: (i) EVs as therapeutic targets, including the targeted inhibition of EV biogenesis and uptake, and the possibility of eliminating tumor-derived EVs; (ii) EVs as delivery nanovectors, where we discuss the latest anti-MM candidates and potential ways to optimize therapeutic efficiency; and (iii) engineered EVs as antitumor vaccines, focusing on the use of tumor cell-derived EVs in immunotherapy. Finally, we address the prospects and challenges of harnessing the therapeutic potential of EVs in clinical transformation.

Size Matters: Curvature and Antigen-Mediated Dual Recognition of Size-Specific Tumor-Derived Exosomes

Accurate identification of tumor-derived exosomes is crucial for advancing cancer diagnosis and therapies. However, distinguishing tumor-derived exosomes is challenging due to the heterogeneity of exosomes, which reflect different sizes and cells of origin. To address this challenge, we introduce the curvature and antigen-mediated proximity ligation assay for tumor-derived exosomes (CAPTURE) strategy, which leverages the size-selective properties of curvature-sensing peptides and specific antigen binding of aptamers. CAPTURE enables highly specific identification and precise quantification of the PD-L1+ exosomes in plasma samples. CAPTURE is proven to be simple, homogeneous, rapid, and highly selective, achieving a 100% specificity in discriminating colorectal cancer (CRC) patients from healthy donors. Overall, the CAPTURE strategy presents a promising avenue for precise and noninvasive cancer diagnosis.

The role and clinical applications of exosomes in cancer drug resistance

Tumor-secreted exosomes are heterogeneous multi-signal messengers that support cancer growth and dissemination by mediating intercellular crosstalk and activating signaling pathways. Distinct from previous reviews, we focus intently on exosome-therapeutic resistance dynamics and summarize the new findings about the regulation of cancer treatment resistance by exosomes, shedding light on the complex processes via which these nanovesicles facilitate therapeutic refractoriness across various malignancies. Future research in exosome biology can potentially transform diagnostic paradigms and therapeutic interventions for cancer management. This review synthesizes recent insights into the exosome-driven regulation of cancer drug resistance, illuminates the sophisticated mechanisms by which these nanovesicles facilitate therapeutic refractoriness across various malignancies, and summarizes some strategies to overcome drug resistance.

Tumor Microenvironment-Derived Exosomes: A Double-Edged Sword for Advanced T Cell-Based Immunotherapy

The tumor microenvironment (TME) plays a crucial role in cancer progression and immune evasion, partially mediated by the activity of the TME-derived exosomes. These extracellular vesicles are pivotal in shaping immune responses through the transfer of proteins, lipids, and nucleic acids between cells, facilitating a complex interplay that promotes tumor growth and metastasis. This review delves into the dual roles of exosomes in the TME, highlighting both their immunosuppressive functions and their emerging therapeutic potential. Exosomes can inhibit T cell function and promote tumor immune escape by carrying immune-modulatory molecules, such as PD-L1, yet they also hold promise for cancer therapy as vehicles for delivering tumor antigens and costimulatory signals. Additionally, the review discusses the intricate crosstalk mediated by exosomes among various cell types within the TME, influencing both cancer progression and responses to immunotherapies. Moreover, this highlights current challenges and future directions. Collectively, elucidating the detailed mechanisms by which TME-derived exosomes mediate T cell function offers a promising avenue for revolutionizing cancer treatment. Understanding these interactions allows for the development of targeted therapies that manipulate exosomal pathways to enhance the immune system's response to tumors.

PEDF-Enriched Extracellular Vesicle for Vessel Normalization to Potentiate Immune Checkpoint Blockade Therapy

The abnormal tumor vasculature acts as the physical and functional barrier to the infiltration and activity of effector T cells, leading to the low response rate of immune checkpoint inhibitors (ICIs). Herein, antiangiogenic extracellular vesicles that enable normalization of the tumor-associated vasculature were prepared to potentiate the efficacy of ICIs. Small extracellular vesicles were exploited as the delivery platform to protect the antiangiogenic protein, pigment epithelium-derived factor (PEDF), from proteolytic degradation. Along with the physicochemical characteristics of the PEDF-enriched extracellular vesicles (P-EVs), their inhibitory effects on migration, proliferation, and tube formation of endothelial cells were investigated in vitro. In tumor-bearing mice, it was confirmed that, compared to bare PEDFs, P-EVs efficiently reduced vessel leakiness, improved blood perfusion, and attenuated hypoxia. Consequently, when combined with anti-PD-1 antibodies, P-EVs remarkably augmented the antitumor immunity, as evidenced by increased infiltration of CD8+ T cells and reduced regulatory T cells. These results suggest that P-EVs are promising therapeutics for tumors refractory to ICIs.

A Self-Cascade Penetrating Brain Tumor Immunotherapy Mediated by Near-Infrared II Cell Membrane-Disrupting Nanoflakes via Detained Dendritic Cells

Immunotherapy can potentially suppress the highly aggressive glioblastoma (GBM) by promoting T lymphocyte infiltration. Nevertheless, the immune privilege phenomenon, coupled with the generally low immunogenicity of vaccines, frequently hampers the presence of lymphocytes within brain tumors, particularly in brain tumors. In this study, the membrane-disrupted polymer-wrapped CuS nanoflakes that can penetrate delivery to deep brain tumors via releasing the cell-cell interactions, facilitating the near-infrared II (NIR II) photothermal therapy, and detaining dendritic cells for a self-cascading immunotherapy are developed. By convection-enhanced delivery, membrane-disrupted amphiphilic polymer micelles (poly(methoxypoly(ethylene glycol)-benzoic imine-octadecane, mPEG-b-C18) with CuS nanoflakes enhances tumor permeability and resides in deep brain tumors. Under low-power NIR II irradiation (0.8 W/cm2), the intense heat generated by well-distributed CuS nanoflakes actuates the thermolytic efficacy, facilitating cell apoptosis and the subsequent antigen release. Then, the positively charged polymer after hydrolysis of the benzoic-imine bond serves as an antigen depot, detaining autologous tumor-associated antigens and presenting them to dendritic cells, ensuring sustained immune stimulation. This self-cascading penetrative immunotherapy amplifies the immune response to postoperative brain tumors but also enhances survival outcomes through effective brain immunotherapy.

Revisiting the advances and challenges in the clinical applications of extracellular vesicles in cancer

Extracellular vesicles (EVs) have been the subject of an exponentially growing number of studies covering their biogenesis mechanisms, isolation and analysis techniques, physiological and pathological roles, and clinical applications, such as biomarker and therapeutic uses. Nevertheless, the heterogeneity of EVs both challenges our understanding of them and presents new opportunities for their potential application. Recently, the EV field experienced a wide range of advances. However, the challenges also remain huge. This review focuses on the recent progress and difficulties encountered in the practical use of EVs in clinical settings. In addition, we also explored the concept of EV heterogeneity to acquire a more thorough understanding of EVs and their involvement in cancer, specifically focusing on the fundamental nature of EVs.

Focal adhesion and actin orientation regulated by cellular geometry determine stem cell differentiation via mechanotransduction

Tuning cell adhesion geometry can affect cytoskeleton organization and the distribution of cytoskeleton forces, which play critical roles in controlling cell functions. To elucidate the geometrical relationship with cytoskeleton force distribution, it is necessary to control cell morphology. In this study, a series of dextral vortex micropatterns were prepared to precisely control cell morphology for investigating the influence of the curvature degree of adhesion curves on intracellular force distribution and stem cell differentiation at a sub-cellular level. Peripherial actin filaments of micropatterned cells were assembled along the adhesion curves and showed different orientations, filament thicknesses and densities. Focal adhesion and cytoskeleton force distribution were dependent on the curvature degree. Intracellular force distribution was also regulated by adhesion curves. The cytoskeleton and force distribution affected the osteogenic differentiation of mesenchymal stem cells through a YAP/TAZ-mediated mechanotransduction process. Thus, regulation of cell adhesion curvature, especially at cytoskeletal filament level, is critical for cell function manipulation. STATEMENT OF SIGNIFICANCE: In this study, a series of dextral micro-vortexes were prepared and used for the culture of human mesenchymal stem cells (hMSCs) to precisely control adhesive curvatures (0°, 30°, 60°, and 90°). The single MSCs on the micropatterns had the same size and shape but showed distinct focal adhesion (FA) and cytoskeleton orientations. Cellular nanomechanics were observed to be correlated with the curvature degrees, subsequently influencing nuclear morphological features. As a consequence, the localization of the mechanotransduction sensor and activator-YAP/TAZ was affected, influencing osteogenic differentiation. The results revealed the pivotal role of adhesive curvatures in the manipulation of stem cell differentiation via the machanotransduction process, which has rarely been investigated.

Piezoelectric Catalysis Induces Tumor Cell Senescence to Boost Chemo-Immunotherapy

Cellular senescence, a vulnerable state of growth arrest, has been regarded as a potential strategy to weaken the resistance of tumor cells, leading to dramatic improvements in treatment efficacy. However, a selective and efficient strategy for inducing local tumor cellular senescence has not yet been reported. Herein, piezoelectric catalysis is utilized to reduce intracellular NAD+ to NADH for local tumor cell senescence for the first time. In detail, a biocompatible nanomedicine (BTO/Rh-D@M) is constructed by wrapping the piezoelectric BaTiO3/(Cp*RhCl2)2 (BTO/Rh) and doxorubicin (DOX) in the homologous cytomembrane with tumor target. After tumors are stimulated by ultrasound, negative and positive charges are generated on the BTO/Rh by piezoelectric catalysis, which reduce the intracellular NAD+ to NADH for cellular senescence and oxidize H2O to reactive oxygen species (ROS) for mitochondrial damage. Thus, the therapeutic efficacy of tumor immunogenic cell death-induced chemo-immunotherapy is boosted by combining cellular senescence, DOX, and ROS. The results indicate that 23.9% of the piezoelectric catalysis-treated tumor cells senesced, and solid tumors in mice disappeared completely after therapy. Collectively, this study highlights a novel strategy to realize cellular senescence utilizing piezoelectric catalysis and the significance of inducing tumor cellular senescence to improve therapeutic efficacy.

Synthetic Peptides with Genetic-Codon-Tailored Affinity for Assembling Tetraspanin CD81 at Cell Interfaces and Inhibiting Cancer Metastasis

Probing biomolecular interactions at cellular interfaces is crucial for understanding and interfering with life processes. Although affinity binders with site specificity for membrane proteins are unparalleled molecular tools, a high demand remains for novel multi-functional ligands. In this study, a synthetic peptide (APQQ) with tight and specific binding to the untargeted extracellular loop of CD81 evolved from a genetically encoded peptide pool. With tailored affinity, APQQ flexibly accesses, site-specifically binds, and forms a complex with CD81, enabling in-situ tracking of the dynamics and activity of this protein in living cells, which has rarely been explored because of the lack of ligands. Furthermore, APQQ triggers the relocalization of CD81 from diffuse to densely clustered at cell junctions and modulates the interplay of membrane proteins at cellular interfaces. Motivated by these, efficient suppression of cancer cell migration, and inhibition of breast cancer metastasis were achieved in vivo.

Exosomal PD-L1 in cancer and other fields: recent advances and perspectives

PD-1/PD-L1 signaling is a key factor of local immunosuppression in the tumor microenvironment. Immune checkpoint inhibitors targeting PD-1/PD-L1 signaling have achieved tremendous success in clinic. However, several types of cancer are particularly refractory to the anti-PD-1/PD-L1 treatment. Recently, a series of studies reported that IFN-γ can stimulate cancer cells to release exosomal PD-L1 (exoPD-L1), which possesses the ability to suppress anticancer immune responses and is associated with anti-PD-1 response. In this review, we introduce the PD-1/PD-L1 signaling, including the so-called 'reverse signaling'. Furthermore, we summarize the immune treatments of cancers and pay more attention to immune checkpoint inhibitors targeting PD-1/PD-L1 signaling. Additionally, we review the action mechanisms and regulation of exoPD-L1. We also introduce the function of exoPD-L1 as biomarkers. Finally, we review the methods for analyzing and quantifying exoPD-L1, the therapeutic strategies targeting exoPD-L1 to enhance immunotherapy and the roles of exoPD-L1 beyond cancer. This comprehensive review delves into recent advances of exoPD-L1 and all these findings suggest that exoPD-L1 plays an important role in both cancer and other fields.

The rising roles of exosomes in the tumor microenvironment reprogramming and cancer immunotherapy

Exosomes are indispensable for intercellular communications. Tumor microenvironment (TME) is the living environment of tumor cells, which is composed of various components, including immune cells. Based on TME, immunotherapy has been recently developed for eradicating cancer cells by reactivating antitumor effect of immune cells. The communications between tumor cells and TME are crucial for tumor development, metastasis, and drug resistance. Exosomes play an important role in mediating these communications and regulating the reprogramming of TME, which affects the sensitivity of immunotherapy. Therefore, it is imperative to investigate the role of exosomes in TME reprogramming and the impact of exosomes on immunotherapy. Here, we review the communication role of exosomes in regulating TME remodeling and the efficacy of immunotherapy, as well as summarize the underlying mechanisms. Furthermore, we also introduce the potential application of the artificially modified exosomes as the delivery systems of antitumor drugs. Further efforts in this field will provide new insights on the roles of exosomes in intercellular communications of TME and cancer progression, thus helping us to uncover effective strategies for cancer treatment.

Hypoxia preconditioning of adipose stem cell-derived exosomes loaded in gelatin methacryloyl (GelMA) promote type H angiogenesis and osteoporotic fracture repair

The challenges posed by delayed atrophic healing and nonunion stand as formidable obstacles in osteoporotic fracture treatment. The processes of type H angiogenesis and osteogenesis emerge as pivotal mechanisms during bone regeneration. Notably, the preconditioning of adipose-derived stem cell (ADSC) exosomes under hypoxic conditions has garnered attention for its potential to augment the secretion and functionality of these exosomes. In the present investigation, we embarked upon a comprehensive elucidation of the underlying mechanisms of hypo-ADSC-Exos within the milieu of osteoporotic bone regeneration. Our findings revealed that hypo-ADSC-Exos harboured a preeminent miRNA, namely, miR-21-5p, which emerged as the principal orchestrator of angiogenic effects. Through in vitro experiments, we demonstrated the capacity of hypo-ADSC-Exos to stimulate the proliferation, migration, and angiogenic potential of human umbilical vein endothelial cells (HUVECs) via the mediation of miR-21-5p. The inhibition of miR-21-5p effectively attenuated the proangiogenic effects mediated by hypo-ADSC-Exos. Mechanistically, our investigation revealed that exosomal miR-21-5p emanating from hypo-ADSCs exerts its regulatory influence by targeting sprouly1 (SPRY1) within HUVECs, thereby facilitating the activation of the PI3K/AKT signalling pathway. Notably, knockdown of SPRY1 in HUVECs was found to potentiate PI3K/AKT activation and, concomitantly, HUVEC proliferation, migration, and angiogenesis. The culminating stage of our study involved a compelling in vivo demonstration wherein GelMA loaded with hypo-ADSC-Exos was validated to substantially enhance local type H angiogenesis and concomitant bone regeneration. This enhancement was unequivocally attributed to the exosomal modulation of SPRY1. In summary, our investigation offers a pioneering perspective on the potential utility of hypo-ADSC-Exos as readily available for osteoporotic fracture treatment.

Anticancer Therapy Targeting Cancer-Derived Extracellular Vesicles

Extracellular vesicles (EVs) are natural lipid nanoparticles secreted by most types of cells. In malignant cancer, EVs derived from cancer cells contribute to its progression and metastasis by facilitating tumor growth and invasion, interfering with anticancer immunity, and establishing premetastasis niches in distant organs. In recent years, multiple strategies targeting cancer-derived EVs have been proposed to improve cancer patient outcomes, including inhibiting EV generation, disrupting EVs during trafficking, and blocking EV uptake by recipient cells. Developments in EV engineering also show promising results in harnessing cancer-derived EVs as anticancer agents. Here, we summarize the current understanding of the origin and functions of cancer-derived EVs and review the recent progress in anticancer therapy targeting these EVs.

Extracellular vesicles for developing targeted hearing loss therapy

Substantial efforts have been made for local administration of small molecules or biologics in treating hearing loss diseases caused by either trauma, genetic mutations, or drug ototoxicity. Recently, extracellular vesicles (EVs) naturally secreted from cells have drawn increasing attention on attenuating hearing impairment from both preclinical studies and clinical studies. Highly emerging field utilizing diverse bioengineering technologies for developing EVs as the bioderived therapeutic materials, along with artificial intelligence (AI)-based targeting toolkits, shed the light on the unique properties of EVs specific to inner ear delivery. This review will illuminate such exciting research field from fundamentals of hearing protective functions of EVs to biotechnology advancement and potential clinical translation of functionalized EVs. Specifically, the advancements in assessing targeting ligands using AI algorithms are systematically discussed. The overall translational potential of EVs is reviewed in the context of auditory sensing system for developing next generation gene therapy.

Photonic control of image-guided ferroptosis cancer nanomedicine

Photonic nanomaterials, characterized by their remarkable photonic tunability, empower a diverse range of applications, including cutting-edge advances in cancer nanomedicine. Recently, ferroptosis has emerged as a promising alternative strategy for effectively killing cancer cells with minimizing therapeutic resistance. Novel design of photonic nanomaterials that can integrate photoresponsive-ferroptosis inducers, -diagnostic imaging, and -synergistic components provide significant benefits to effectively trigger local ferroptosis. This review provides a comprehensive overview of recent advancements in photonic nanomaterials for image-guided ferroptosis cancer nanomedicine, offering insights into their strengths, constraints, and their potential as a future paradigm in cancer treatment.

Amphipathic Helices Can Sense Both Positive and Negative Curvatures of Lipid Membranes

Curvature sensing is an essential ability of biomolecules to preferentially localize to membrane regions of a specific curvature. It has been shown that amphipathic helices (AHs), helical peptides with both hydrophilic and hydrophobic regions, could sense a positive membrane curvature. The origin of this AH sensing has been attributed to their ability to exploit lipid-packing defects that are enhanced in regions of positive curvature. In this study, we revisit an alternative framework where AHs act as sensors of local internal stress within the membrane, suggesting the possibility of an AH sensing a negative membrane curvature. Using molecular dynamics simulations, we gradually tuned the hydrophobicity of AHs, thereby adjusting their insertion depth so that the curvature preference of AHs is switched from positive to negative. This study suggests that highly hydrophobic AHs could preferentially localize proteins to regions of a negative membrane curvature.

Immunogenic Extracellular Vesicles Derived from Endoplasmic Reticulum-Stressed Tumor Cells: Implications as the Therapeutic Cancer Vaccine

Tumor-derived extracellular vesicles (TDEs) have potential for therapeutic cancer vaccine applications since they innately possess tumor-associated antigens, mediate antigen presentation, and can incorporate immune adjuvants for enhanced vaccine efficacy. However, the original TDEs also contain immune-suppressive proteins. To address this, we proposed a simple yet powerful preconditioning method to improve the overall immunogenicity of the TDEs. This approach involved inducing endoplasmic reticulum (ER) stress on parental tumor cells via N-glycosylation inhibition with tunicamycin. The generated immunogenic TDEs (iTDEs) contained down-regulated immunosuppressive proteins and up-regulated immune adjuvants, effectively activating dendritic cells (DCs) in vitro. Furthermore, in vivo evidence from a tumor-bearing mouse model showed that iTDEs activated DCs, enabling cytotoxic T lymphocytes (CTLs) to target tumors, and eventually established a systemic antitumor immune response. Additionally, iTDEs significantly delayed tumor recurrence in a postsurgery model compared with control groups. These findings highlight the immense potential of our strategy for utilizing TDEs to develop effective cancer vaccines.

Challenges Coexist with Opportunities: Spatial Heterogeneity Expression of PD-L1 in Cancer Therapy

Cancer immunotherapy using anti-programmed death-ligand 1 (PD-L1) antibodies has been used in various clinical applications and achieved certain results. However, such limitations as autoimmunity, tumor hyperprogression, and overall low patient response rate impede its further clinical application. Mounting evidence has revealed that PD-L1 is not only present in tumor cell membrane but also in cytoplasm, exosome, or even nucleus. Among these, the dynamic and spatial heterogeneous expression of PD-L1 in tumors is mainly responsible for the unsatisfactory efficacy of PD-L1 antibodies. Hence, numerous studies focus on inhibiting or degrading PD-L1 to improve immune response, while a comprehensive understanding of the molecular mechanisms underlying spatial heterogeneity of PD-L1 can fundamentally transform the current status of PD-L1 antibodies in clinical development. Herein, the concept of spatial heterogeneous expression of PD-L1 is creatively introduced, encompassing the structure and biological functions of various kinds of PD-L1 (including mPD-L1, cPD-L1, nPD-L1, and exoPD-L1). Then an in-depth analysis of the regulatory mechanisms and potential therapeutic targets of PD-L1 is provided, seeking to offer a solid basis for future investigation. Moreover, the current status of agents is summarized, especially small molecular modulators development directed at these new targets, offering a novel perspective on potential PD-L1 therapeutics strategies.

Membrane Proteins and Membrane Curvature: Mutual Interactions and a Perspective on Disease Treatments

The pathogenesis of various diseases often involves an intricate interplay between membrane proteins and membrane curvature. Understanding the underlying mechanisms of this interaction could offer novel perspectives on disease treatment. In this review, we provide an introduction to membrane curvature and its association with membrane proteins. Furthermore, we delve into the impact and potential implications of this interaction in the context of disease treatment. Lastly, we discuss the prospects and challenges associated with harnessing these interactions for effective disease management, aiming to provide fresh insights into therapeutic strategies.