Erythrocyte membrane bioengineered nanoprobes via indocyanine green-directed assembly for single NIR laser-induced efficient photodynamic/photothermal theranostics

Surface-engineered erythrocyte membrane-camouflage fluorescent bioprobe for precision ovarian cancer surgery

PURPOSE

Fluorescence imaging-guided surgery has been used in oncology. However, for tiny tumors, the current imaging probes are still difficult to achieve high-contrast imaging, leading to incomplete resection. In this study, we achieved precise surgical resection of tiny metastatic cancers by constructing an engineering erythrocyte membrane-camouflaged bioprobe (AR-M@HMSN@P).

METHODS

AR-M@HMSN@P combined the properties of aggregation-induced emission luminogens (AIEgens) named PF3-PPh3 (P), with functional erythrocyte membrane modified by a modular peptide (AR). Interestingly, AR was composed of an asymmetric tripodal pentapeptide scaffold (GGKGG) with three appended modulars: KPSSPPEE (A6) peptide, RRRR (R4) peptide and cholesterol. To verify the specificity of the probe in vitro, SKOV3 cells with overexpression of CD44 were used as the positive group, and HLF cells with low expression of CD44 were devoted as the control group. The AR-M@HMSN@P fluorescence imaging was utilized to provide surgical guidance for the removal of micro-metastatic lesions.

RESULTS

In vivo, the clearance of AR-M@HMSN@P by the immune system was reduced due to the natural properties inherited from erythrocytes. Meanwhile, the A6 peptide on AR-M@HMSN@P was able to specifically target CD44 on ovarian cancer cells, and the electrostatic attraction between the R4 peptide and the cell membrane enhanced the firmness of this targeting. Benefiting from these multiple effects, AR-M@HMSN@P achieved ultra-precise tumor imaging with a signal-to-noise ratio (SNR) of 15.2, making it possible to surgical resection of tumors < 1 mm by imaging guidance.

CONCLUSION

We have successfully designed an engineered fluorescent imaging bioprobe (AR-M@HMSN@P), which can target CD44-overexpressing ovarian cancers for precise imaging and guide the resection of minor tumors. Notably, this work holds significant promise for developing biomimetic probes for clinical imaging-guided precision cancer surgery by exploiting their externally specified functional modifications.

Biomimetic Cell Membrane-Coated Nanoparticles for Cancer Theranostics

Nanoparticles can enhance drugs accumulating at the tumor site and hold tremendous promise for achieving effective tumor treatment. However, due to the complexity of cancer heterogeneity and suppressive tumor microenvironment, the delivery of traditional nanoparticles has poor infiltration and off-target effects, making it difficult to control the drug release rate and causing off-target toxicity. In recent years, cell membrane-coated biomimetic nanoparticles have been developed, which have both the natural characteristics of biomembranes and the physical characteristics of traditional nanoparticles, thus improving the homologous targeting ability of nanoparticles to tumor cells and better biocompatibility. In this paper, we reviewed the application of single cell membrane and hybrid cell membrane-coated biomimetic nanoparticles in the integration for tumor diagnosis and treatment. We talked about the preparation methods of cell membrane-coated nanoparticles, the targeting mechanisms, and the effects of imaging and therapeutic outcomes of different cell membrane-coated biomimetic nanoparticles in detail. Finally, we discussed the existing problems and prospects of cell membrane-coated biomimetic nanomaterials.

Biomimetic Ghost Nanomedicine-Based Optotheranostics for Cancer

Theranostic medicine combines diagnostics and therapeutics, focusing on solid tumors at minimal doses. Optically activated photosensitizers are significant examples owing to their photophysical and chemical properties. Several optotheranostics have been tested that convert light to imaging signals, therapeutic radicals, and heat. Upon light exposure, conjugated photosensitizers kill tumor cells by producing reactive oxygen species and heat or by releasing cancer antigens. Despite clinical trials, these molecularly conjugated photosensitizers require protection from their surroundings and a localized direction for site-specific delivery during blood circulation. Therefore, cell membrane biomimetic ghosts have been proposed for precise and safe delivery of these optically active large molecules, which are clinically relevant because of their biocompatibility, long circulation time, bypass of immune cell recognition, and targeting ability. This review focuses on the role of biomimetic nanoparticles in the treatment and diagnosis of tumors through light-mediated diagnostics and therapy, providing insights into their preclinical and clinical status.

Osteosarcoma-targeted Cu and Ce based oxide nanoplatform for NIR II fluorescence/magnetic resonance dual-mode imaging and ros cascade amplification along with immunotherapy

BACKGROUND

As the lethal bone tumor, osteosarcoma often frequently occurs in children and adolescents with locally destructive and high metastasis. Distinctive kinds of nanoplatform with high therapeutical effect and precise diagnosis for osteosarcoma are urgently required. Multimodal optical imaging and programmed treatment, including synergistic photothermal-chemodynamic therapy (PTT-CDT) elicits immunogenetic cell death (ICD) is a promising strategy that possesses high bio-imaging sensitivity for accurate osteosarcoma delineating as well as appreciable therapeutic efficacy with ignorable side-effects.

METHODS AND RESULTS

In this study, mesoporous Cu and Ce based oxide nanoplatform with Arg-Gly-Asp (RGD) anchoring is designed and successfully constructed. After loading with indocyanine green, this nanoplatform can be utilized for precisely targeting and efficaciously ablating against osteosarcoma via PTT boosted CDT and the closely following ICD stimulation both in vitro and in vivo. Besides, it provides off-peak fluorescence bio-imaging in the second window of near-infrared region (NIR II, 1000-1700 nm) and Magnetic resonance signal, serves as the dual-mode contrast agents for osteosarcoma tissue discrimination.

CONCLUSION

Tumor targeted Cu&Ce based mesoporous nanoplatform permits efficient osteosarcoma suppression and dual-mode bio-imaging that opens new possibility for effectively diagnosing and inhibiting the clinical malignant osteosarcoma.

Nano-modulators with the function of disrupting mitochondrial Ca2+ homeostasis and photothermal conversion for synergistic breast cancer therapy

Breast cancer treatment has been a global puzzle, and apoptosis strategies based on mitochondrial Ca2+ overload have attracted extensive attention. However, various limitations of current Ca2+ nanogenerators make it difficult to maintain effective Ca2+ overload concentrations. Here, we constructed a multimodal Ca2+ nano-modulator that, for the first time, combined photothermal therapy (PTT) and mitochondrial Ca2+ overload strategies to inhibit tumor development. By crosslinking sodium alginate (SA) on the surface of calcium carbonate (CaCO3) nanoparticles encapsulating with Cur and ICG, we prepared a synergistic Ca2+ nano-regulator SA/Cur@CaCO3-ICG (SCCI). In vitro studies have shown that SCCI further enhanced photostability while preserving the optical properties of ICG. After uptake by tumor cells, SCCI can reduce mitochondrial membrane potential and down-regulate ATP production by producing large amounts of Ca2+ at low pH. Near-infrared light radiation (NIR) laser irradiation made the tumor cells heat up sharply, which not only accelerated the decomposition of CaCO3, but also produced large amounts of reactive oxygen species (ROS) followed by cell apoptosis. In vivo studies have revealed that the Ca2+ nano-regulators had excellent targeting, biocompatibility, and anti-tumor effects, which can significantly inhibit the proliferation of tumor cells and play a direct killing effect. These findings indicated that therapeutic strategies based on ionic interference and PTT had great therapeutic potential, providing new insights into antitumor therapy.

Advanced targeted drug delivery by bioengineered white blood cell-membrane camouflaged nanoparticulate delivery nanostructures

Targeted drug delivery has emerged as a pivotal approach within precision medicine, aiming to optimize therapeutic efficacy while minimizing systemic side effects. Leukocyte membrane coated nanoparticles (NPs) have attracted a lot of interest as an effective approach for delivering targeted drugs, capitalizing on the natural attributes of leukocytes to achieve site-specific accumulation, and heightened therapeutic outcomes. An overview of the present state of the targeted medication delivery research is given in this review. Notably, Leukocyte membrane-coated NPs offer inherent advantages such as immune evasion, extended circulation half-life, and precise homing to inflamed or diseased tissues through specific interactions with adhesion molecules. leukocyte membrane-coated NPs hold significant promise in advancing targeted drug delivery for precision medicine. As research progresses, they are anticipated to contribute to improved therapeutic outcomes, enabling personalized and effective treatments for a wide range of diseases and conditions. The review covers the method of preparation, characterization, and biological applications of leucocytic membrane coated NPs. Further, patents related factors, gap of translation from laboratory to clinic, and future prospective were discussed in detail. Overall, the review covers extensive literature to establish leucocytic membrane NPs for targeted drug delivery.

Advance Progress in Assembly Mechanisms of Carrier-Free Nanodrugs for Cancer Treatment

Nanocarriers have been widely studied and applied in the field of cancer treatment. However, conventional nanocarriers still suffer from complicated preparation processes, low drug loading, and potential toxicity of carriers themselves. To tackle the hindrance, carrier-free nanodrugs with biological activity have received increasing attention in cancer therapy. Extensive efforts have been made to exploit new self-assembly methods and mechanisms to expand the scope of carrier-free nanodrugs with enhanced therapeutic performance. In this review, we summarize the advanced progress and applications of carrier-free nanodrugs based on different types of assembly mechanisms and strategies, which involved noncovalent interactions, a combination of covalent bonds and noncovalent interactions, and metal ions-coordinated self-assembly. These carrier-free nanodrugs are introduced in detail according to their assembly and antitumor applications. Finally, the prospects and existing challenges of carrier-free nanodrugs in future development and clinical application are discussed. We hope that this comprehensive review will provide new insights into the rational design of more effective carrier-free nanodrug systems and advancing clinical cancer and other diseases (e.g., bacterial infections) infection treatment.

Near-infrared photodynamic and photothermal co-therapy based on organic small molecular dyes

Near-infrared (NIR) organic small molecule dyes (OSMDs) are effective photothermal agents for photothermal therapy (PTT) due to their advantages of low cost and toxicity, good biodegradation, and strong NIR absorption over a wide wavelength range. Nevertheless, OSMDs have limited applicability in PTT due to their low photothermal conversion efficiency and inadequate destruction of tumor regions that are nonirradiated by NIR light. However, they can also act as photosensitizers (PSs) to produce reactive oxygen species (ROS), which can be further eradicated by using ROS-related therapies to address the above limitations of PTT. In this review, the synergistic mechanism, composition, and properties of photodynamic therapy (PDT)-PTT nanoplatforms were comprehensively discussed. In addition, some specific strategies for further improving the combined PTT and PDT based on OSMDs for cancer to completely eradicate cancer cells were outlined. These strategies include performing image-guided co-therapy, enhancing tumor infiltration, increasing H2O2 or O2 in the tumor microenvironment, and loading anticancer drugs onto nanoplatforms to enable combined therapy with phototherapy and chemotherapy. Meanwhile, the intriguing prospects and challenges of this treatment modality were also summarized with a focus on the future trends of its clinical application.

Innovative Design Strategies Advance Biomedical Applications of Phthalocyanines

Owing to their long absorption wavelengths, high molar absorptivity, and tunable photosensitivity, phthalocyanines have been widely used in photodynamic therapy (PDT). However, phthalocyanines still face the drawbacks of poor targeting, "always-on" photosensitizing properties, and unsatisfactory therapeutic efficiency, which limit their wide applications in biomedical fields. Thus, new design strategies such as modification of targeting molecules, formation of nanoparticles, and activating photosensitizers are developed to improve the above defects. Notably, recent studies have shown that novel phthalocyanines are not only used in fluorescence imaging and PDT, but also in photoacoustic imaging, photothermal imaging, sonodynamic therapy, and photothermal therapy. This review focuses on recent design strategies, applications in biomedicine, and clinical development of phthalocyanines, providing ideas and references for the design and application of phthalocyanine, so as to promote their future transformation into clinical applications.

Red blood cells: a potential delivery system

Red blood cells (RBCs) are the most abundant cells in the body, possessing unique biological and physical properties. RBCs have demonstrated outstanding potential as delivery vehicles due to their low immunogenicity, long-circulating cycle, and immune characteristics, exhibiting delivery abilities. There have been several developments in understanding the delivery system of RBCs and their derivatives, and they have been applied in various aspects of biomedicine. This article compared the various physiological and physical characteristics of RBCs, analyzed their potential advantages in delivery systems, and summarized their existing practices in biomedicine.

Medical Applications and Advancement of Near Infrared Photosensitive Indocyanine Green Molecules

Indocyanine green (ICG) is an important kind of near infrared (NIR) photosensitive molecules for PTT/PDT therapy as well as imaging. When exposed to NIR light, ICG can produce reactive oxygen species (ROS), which can kill cancer cells and pathogenic bacteria. Moreover, the absorbed light can also be converted into heat by ICG molecules to eliminate cancer cells. In addition, it performs exceptionally well in optical imaging-guided tumor therapy and antimicrobial therapy due to its deeper tissue penetration and low photobleaching properties in the near-infrared region compared to other dyes. In order to solve the problems of water and optical stability and multi-function problem of ICG molecules, composite nanomaterials based on ICG have been designed and widely used, especially in the fields of tumors and sterilization. So far, ICG molecules and their composite materials have become one of the most famous infrared sensitive materials. However, there have been no corresponding review articles focused on ICG molecules. In this review, the molecular structure and properties of ICG, composite material design, and near-infrared light- triggered anti-tumor, and antibacterial, and clinical applications are reviewed in detail, which of great significance for related research.

Bioengineered nanogenerator with sustainable reactive oxygen species storm for self-reinforcing sono-chemodynamic oncotherapy

Oxidative stress-based antitumor modalities derived from reactive oxygen species (ROS) storms have attracted increasing attention. Nevertheless, low delivery efficiency, poor selectivity, hypoxia and overexpressed glutathione (GSH) have severely restricted the sustainable generation of the ROS storm in tumor cells. Herein, we design a bioengineered nanogenerator by coordination-driven co-assembly of sonosensitizer indocyanine green (ICG), Fenton-like agent copper ion (Cu^Ⅱ) and mitochondrial respiratory inhibitor metformin (MET), which is then camouflaged by a cancer cytomembrane to induce a sustainable intracellular ROS storm for on-demand self-reinforcing sono-chemodynamic oncotherapy. Such a nanogenerator with a core-shell structure, suitable diameter and outstanding stability can efficiently accumulate in tumor regions and then internalize into tumor cells through the camouflaging and homologous targeting strategy of the cancer cytomembrane. The nanogenerator shows an exceptional instability under the triple stimulations of acidic lysosomes, overexpressed GSH and ultrasound (US) radiation, thereby resulting in the rapid disassembly and burst drug release. Interestingly, the released MET significantly enhances the sonodynamic therapy (SDT) efficacy of the released ICG by inhibiting mitochondrial respiration and meanwhile the released Cu^Ⅱ obviously reduces ROS elimination by downregulating overexpressed GSH for self-amplifying and self-protecting the intracellular ROS storm. Moreover, such a nanogenerator almost completely achieves the tumor ablation in vivo in a single therapy cycle. Taken together, our bioengineered nanogenerator with a sustainable ROS storm can provide a promising strategy for ROS storm-based oncotherapy.

Red Blood Cell Membrane-coated Functionalized Au Nanocage as a Biomimetic Platform for Improved MicroRNA Delivery in Hepatocellular Carcinoma

Dysregulation of microRNAs (miRNAs) expression is closely related to cancers and managing miRNA expression holds great promise for cancer therapy. However, their wide clinical application has been hampered by their poor stability, short half-life and non-specific biodistribution in vivo. Herein, a novel biomimetic platform designated as RHAuNCs-miRNA for improved miRNA delivery was prepared through wrapping miRNA-loaded functionalized Au nanocages (AuNCs) with red blood cell (RBC) membrane. RHAuNCs-miRNA not only successfully loaded miRNAs but also effectively protected them from enzymatic degradation. With good stability, RHAuNCs-miRNA had the characteristics of photothermal conversion and sustained release. Cellular uptake of RHAuNCs-miRNA by SMMC-7721 cells was in a time-dependent manner via clathrin- and caveolin-mediated endocytosis. The uptake of RHAuNCs-miRNAs was affected by cell types and improved by mild near infrared (NIR) laser irradiation. More importantly, RHAuNCs-miRNA exhibited a prolonged circulation time without the occurrence of accelerated blood clearance (ABC) in vivo, resulting in efficient delivery to tumor tissues. This study may demonstrate the great potential of RHAuNCs-miRNA for improved miRNAs delivery.

Nanoparticles-based phototherapy systems for cancer treatment: Current status and clinical potential

Remarkable progress in phototherapy has been made in recent decades, due to its non-invasiveness and instant therapeutic efficacy. In addition, with the rapid development of nanoscience and nanotechnology, phototherapy systems based on nanoparticles or nanocomposites also evolved as an emerging hotspot in nanomedicine research, especially in cancer. In this review, first we briefly introduce the history of phototherapy, and the mechanisms of phototherapy in cancer treatment. Then, we summarize the representative development over the past three to five years in nanoparticle-based phototherapy and highlight the design of the innovative nanoparticles thereof. Finally, we discuss the feasibility and the potential of the nanoparticle-based phototherapy systems in clinical anticancer therapeutic applications, aiming to predict future research directions in this field. Our review is a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology, nanoscience and cancer.

Erythrocyte-Inspired Functional Materials for Biomedical Applications

Erythrocytes are the most abundant cells in the blood. As the results of long-term natural selection, their specific biconcave discoid morphology and cellular composition are responsible for gaining excellent biological performance. Inspired by the intrinsic features of erythrocytes, various artificial biomaterials emerge and find broad prospects in biomedical applications such as therapeutic delivery, bioimaging, and tissue engineering. Here, a comprehensive review from the fabrication to the applications of erythrocyte-inspired functional materials is given. After summarizing the biomaterials mimicking the biological functions of erythrocytes, the synthesis strategies of particles with erythrocyte-inspired morphologies are presented. The emphasis is on practical biomedical applications of these bioinspired functional materials. The perspectives for the future possibilities of the advanced erythrocyte-inspired biomaterials are also discussed. It is hoped that the summary of existing studies can inspire researchers to develop novel biomaterials; thus, accelerating the progress of these biomaterials toward clinical biomedical applications.

A new chitosan-based thermosensitive nanoplatform for combined photothermal and chemotherapy

Targeting the delivery of anti-cancer drugs to a tumor site is essential for effective treatment and to ensure minimal damage to healthy cells and tissues. In this work, a chitosan-based nanoplatform was constructed for combined photothermal therapy and chemotherapy of breast cancer. The pH-sensitive and biocompatible biopolymer chitosan (CS) was grafted with N-vinylcaprolactam (NVCL) and modified with biotin (Bio), imparting it with temperature sensitive property and also the ability for active targeting. The polymer self-assembled to give nanoparticles (NPs) loaded with indocyanine green (ICG) and doxorubicin (DOX). When the NPs are exposed to near-infrared (NIR) laser irradiation, ICG converts the light to heat, inducing a significant phase transition in the NPs and facilitating the release of the drug cargo. In addition, the solubility of chitosan is increased in the slightly acidic microenvironment of the tumor site, which also promotes drug release. A detailed analysis of the NPs both in vitro and in vivo showed that the carrier system is biocompatible, while the drug-loaded NPs are selectively taken up by cancer cells. Particularly when augmented with NIR irradiation, this leads to potent cell death in vitro and also in an in vivo murine xenograft model of breast cancer.

Biomimetic dual-responsive bioengineered nanotheranostics for intracellular cascade-synthesizing chemo-drugs and efficient oncotherapy

Intracellular-synthesized chemo-drugs based on the inherent characteristics of the tumor microenvironment (TME) have been extensively applied in oncotherapy. However, combining other therapeutic strategies to convert nontoxic small molecules into toxic small-molecule chemo-drugs in the TME is still a huge challenge. To address this issue, herein we have developed a biomimetic dual-responsive bioengineered nanotheranostics system via the supramolecular co-assembly of the nontoxic small-molecule 1,5-dihydroxynaphthalene (DHN) and small-molecule photosensitizer indocyanine green (ICG) followed by surface cloaking through red blood cell membranes (RBCs) for intracellular cascade-synthesizing chemo-drugs and efficient oncotherapy. Such nanotheranostics with a suitable diameter, core-shell structure, ultrahigh dual-drug payload rate, and excellent stability can efficiently accumulate in tumor regions and then internalize into tumor cells. Under the dual stimulations of near-infrared laser irradiation and acidic lysosomes, the nanotheranostics system exhibited exceptional instability under heat-primed membrane rupture and pH decrease, thereby achieving rapid disassembly and on-demand drug release. Furthermore, the released ICG can efficiently convert ³O₂ into ¹O₂. After that, the generated ¹O₂ can efficiently oxidize the released nontoxic DHN into the highly toxic chemo-drug juglone, thereby realizing intracellular cascade-synthesizing chemo-drugs and synergistic photodynamic-chemotherapy while reducing detrimental side effects on normal cells or tissues. Overall, it is envisioned that RBC-cloaked nanotheranostics with intracellular cascade-synthesizing chemo-drugs can provide a promising strategy for intracellular chemo-drug synthesis-based oncotherapy.

Red blood cell membrane nanoparticles for tumor phototherapy

Non-invasive phototherapy includes photodynamic therapy (PDT) and photothermal therapy (PTT), and has garnered special interest in anti-tumor therapy. However, traditional photosensitizers or photothermal agents are faced with major challenges, including easy recognition by immune system, rapid clearance from blood circulation, and low accumulation in target sites. Combining the characteristics of natural cell membrane with the characteristics of photosensitizer or photothermal agent is an important technology to achieve the ideal therapeutic effect of cancer. Red cell membrane (RBMs) coated can disguise phototherapy agents as endogenous substances, thus constructing a new nano bionic therapeutic platform, resisting blood clearance and prolonging circulation time. At present, a variety of phototherapy agents based on Nano-RBMs have been isolated or designed. In this review, firstly, the basic principles of Nano-RBMs and phototherapy are expounded respectively. Then, the latest progress of Nano-RBMs for PDT, PTT and PDT/PTT applications in recent five years has been introduced respectively. Finally, the problems and challenges of Nano-RBMs in the field of phototherapy are put forward.

Synergistic chemotherapy and phototherapy based on red blood cell biomimetic nanomaterials

Novel drug delivery systems (DDSs) have become the mainstay of research in targeted cancer therapy. By combining different therapeutic strategies, potential DDSs and synergistic treatment approaches are needed to effectively deal with evolving drug resistance and the adverse effects of cancer. Nowadays, developing and optimizing human cell-based DDSs has become a new research strategy. Among them, red blood cells can be used as DDSs as they significantly enhance the pharmacokinetics of the transported drug cargo. Phototherapy, as a novel adjuvant in cancer treatment, can be divided into photodynamic therapy and photothermal therapy. Phototherapy using erythropoietic nanocarriers to mimic the unique properties of erythrocytes and overcome the limitations of existing DDSs shows excellent prospects in clinical settings. This review provides an overview of the development of photosensitizers and research on bio-nano-delivery systems based on erythrocytes and erythrocyte membranes that are used in achieving synergistic outcomes during phototherapy/chemotherapy.

Membrane-wrapped nanoparticles for photothermal cancer therapy

Cancer is a global health problem that needs effective treatment strategies. Conventional treatments for solid-tumor cancers are unsatisfactory because they cause unintended harm to healthy tissues and are susceptible to cancer cell resistance. Nanoparticle-mediated photothermal therapy is a minimally invasive treatment for solid-tumor cancers that has immense promise as a standalone therapy or adjuvant to other treatments like chemotherapy, immunotherapy, or radiotherapy. To maximize the success of photothermal therapy, light-responsive nanoparticles can be camouflaged with cell membranes to endow them with unique biointerfacing capabilities that reduce opsonization, prolong systemic circulation, and improve tumor delivery through enhanced passive accumulation or homotypic targeting. This ensures a sufficient dose of photoresponsive nanoparticles arrives at tumor sites to enable their complete thermal ablation. This review summarizes the state-of-the-art in cell membrane camouflaged nanoparticles for photothermal cancer therapy and provides insights to the path forward for clinical translation.

Recent advances in erythrocyte membrane-camouflaged nanoparticles for the delivery of anti-cancer therapeutics

INTRODUCTION

Red blood cell (or erythrocyte) membrane-camouflaged nanoparticles (RBC-NPs) not only have a superior circulation life and do not induce accelerated blood clearance, but also possess special functions, which offers great potential in cancer therapy.

AREAS COVERED

This review focuses on the recent advances of RBC-NPs for delivering various agents to treat cancers in light of their vital role in improving drug delivery. Meanwhile, the construction and in vivo behavior of RBC-NPs are discussed to provide an in-depth understanding of the basis of RBC-NPs for improved cancer drug delivery.

EXPERT OPINION

Although RBC-NPs are quite prospective in delivering anti-cancer therapeutics, they are still in their infancy stage and many challenges need to be overcome for successful translation into the clinic. The preparation and modification of RBC membranes, the optimization of coating methods, the scale-up production and the quality control of RBC-NPs, and the drug loading and release should be carefully considered in the clinical translation of RBC-NPs for cancer therapy.

Indocyanine green potentiated paclitaxel nanoprodrugs for imaging and chemotherapy

Self-assembled prodrug nanoparticles with tumor-responsive capacity have great potential in tumor visualization and treatment. However, the nanoparticle formulas usually contain multiple components, especially polymeric materials, which result in various potential issues. Herein, we report an indocyanine green (ICG)-driven assembly of paclitaxel prodrugs integrating near-infrared fluorescence imaging and tumor-specific chemotherapy. By feat of the hydrophilic merit of ICG, paclitaxel dimer could form more uniformly monodispersed nanoparticles. This two-in-one strategy reinforces the complementary advantages, resulting in superior assembly behavior, robust colloidal stability, enhanced tumor accumulation as well as desirable near-infrared imaging and in vivo feedback of chemotherapy. The in vivo experiments validated the prodrug activation at tumor sites as evidenced by enhanced fluorescence intensity, potent tumor growth suppression, and reduced systemic toxicity compared with commercial Taxol. The universality of ICG potentiated strategy toward photosensitizers and fluorescence dyes was confirmed. This presentation provides deep insight into the feasibility of constructing clinical-close alternatives for improving antitumor efficacy.

pH/Thermal-Sensitive Nanoplatform Capable of On-Demand Specific Release to Potentiate Drug Delivery and Combinational Hyperthermia/Chemo/Chemodynamic Therapy

Therapeutic platforms with spatiotemporal control were recently of considerable interest. However, the site-specific regulation of chemotherapeutics release remains an enormous challenge. Herein, a versatile nanoplatform capable of tumor-specific delivery and controlled drug release, coined as PDDFe, was constructed for elevating cancer theranostics. Iron-oxide nanoparticles (IONPs) and doxorubicin (Dox) were encapsulated in pH/thermal-sensitive micelles composed of poly(ethylene)glycol-poly(β-amino esters) and dipalmitoyl phosphatidylcholine to obtain tumor-targeted dual-responsive nanoplatforms. With remarkable magnetic targeting effects, PDDFe specifically accumulated at tumor locations. After internalization by cancer cells, the acidic environment and localized heat generated by hyperthermia therapy would spur PDDFe to become loose and collapse to liberate its payload. In addition to boosting the release, the increased temperature also resulted in direct tumor damage. Meanwhile, the released Dox and IONPs, respectively, stimulated chemotherapy and chemodynamic therapy to jointly destroy cancer, thus leading to a pronounced therapeutic effect. In vivo magnetic resonance/fluorescence/photoacoustic imaging experiments validated that the dual-sensitive nanoplatforms were able to accumulate at the tumor sites. Treatment with PDDFe followed by alternating magnetic field and laser irradiation could prime hyperthermia/chemo/chemodynamic therapy to effectively retard tumor growth. This work presents a nanoplatform with a site-specific controlled release characteristic, showing great promises in potentiating drug delivery and advancing combinational cancer therapy.

Multifunctional theranostic nanoplatform loaded with autophagy inhibitor for enhanced photothermal cancer therapy under mild near-infrared irradiation

Photothermal therapy (PTT) usually causes hyperthermia and damages healthy tissues. Developing a PTT platform with enhanced therapeutic effects and reduced side effects to normal tissues attracts increasing attention. Herein, we developed a multifunctional theranostic nanoplatform using poly(lactic-co-glycolic acid) (PLGA) loaded with near-infrared (NIR) photothermal agent (new indocyanine green IR820), fluorescence imaging agent (ZnCdSe/ZnS quantum dots, QDs) and autophagy inhibitor (chloroquine, CQ). These PLGA/IR820/Fluorescence imaging agent/CQ co-loading nanoparticles (termed PIFC NPs) displayed photothermal effects, enhanced the stability of IR820 in vivo, and enabled QDs to have stable fluorescent signals in vitro and in vivo. The PIFC NPs with particle size around 240 nm aggregated to tumor sites through the high permeability and retention effects of solid tumors. The intracellular delivery of CQ molecules through PIFC NPs significantly attenuated the degradation of autophagic lysosomes in tumor cells and effectively inhibited the autophagy mediated repair of photothermal damaged cells. Under milder NIR irradiation conditions, PIFC NPs exhibited high antitumor effect. By regulating autophagy, PTT can be effectively sensitized, which will provide a new idea for future cancer treatment research.

Prolonged blood circulation outperforms active targeting for nanocarriers-mediated enhanced hepatocellular carcinoma therapy in vivo

Successful hepatocellular carcinoma (HCC) therapy in vivo remains a significant challenge due to the down-regulated expression of the receptors on the surface of tumor cells for compromised active targeting efficiency and cellular uptake of nanoparticles (NPs)-based drug delivery systems (DDSs) and "accelerated blood clearance" and premature unpackaging of NPs in vivo induced by the poly(ethylene glycol)ylation (PEGylation). Inspired by the repeatedly highlighted prolonged blood circulation property of RBCm-camouflaged NPs, we hypothesis that the prolonged blood circulation property resulting from RBCm coating outperforms the active targeting mechanisms of various targeting ligands for enhanced HCC therapy in vivo. Clarification of this hypothesis is therefore of great significance and urgency to break the afore mentioned bottlenecks that hamper the efficient HCC treatment in vivo. For this purpose, we reported in this study the first identification of a determining factor of nanocarriers for enhanced HCC therapy in vivo by the use of the previously fabricated pectin-doxorubicin nanoparticles (PDC-NPs) as a typical example, i.e., the natural RBCm was used as a stealth coating of PDC-NPs for the fabrication of biomimetic DDSs, PDC@RBC-NPs via hypotonic dialysis and mechanical co-extrusion methods. Comprehensive in vitro and in vivo evaluation and comparison of the properties and performance of PDC@RBC-NPs and PDC-NPs were performed in terms of colloidal stability, biosafety, drug release profiles, macrophage escape, anti-HCC effect. The resulting PDC@RBC-NPs outperformed PDC-NPs for HCC therapy in vitro and in vivo. Notably, PDC@RBC-NPs-treated BALB/c nude mice showed a significantly smaller final average tumor volume of 613 mm³ after 16 days than the PDC-NPs-treated group with an average value of 957 mm³. Therefore, the PDC@RBC-NPs developed herein showed great potential for clinical transformations due to the facile preparation and superior therapeutic efficiency against HCC. Most importantly, prolonged blood circulation was identified as a determining factor of nanocarriers instead of active targeting for enhanced HCC therapy in vivo, which could be used to direct the future design and development of advanced DDSs with greater therapeutic efficiency for HCC.

A Novel Nanoprobe for Targeted Imaging and Photothermal/Photodynamic Therapy of Lung Cancer

An effective accumulation of the photosensitive drugs in the target tissues is a vital prerequisite for obtaining the optimal photodynamic or photothermal treatment effects during the lung cancer treatment. In this study, porous Fe₃O₄ nanoparticles were used to efficiently load the near-infrared photosensitive drug indocyanine green (ICG) in the pores (denoted as Fe/ICG) by electrostatic adsorption. Subsequently, Fe/ICG was modified with hyaluronic acid (HA) to construct a novel target nanoprobe (denoted as Fe/ICG@HA). Fe/ICG@HA exhibited not only excellent ICG loading and stability but also a significant uptake by the lung cancer cells owing to the targeting characteristics. Meanwhile, the nanoprobe improved the efficiency of thermal conversion and generation of singlet oxygen, thereby resulting in an optimal photothermal/photodynamic therapy effect. Based on the in vivo experiments and T2-magnetic resonance (MR) imaging, the nanoprobe was confirmed to possess excellent tumor-targeting abilities. Furthermore, under 808 nm laser irradiation, a significant therapeutic effect was observed on the tumor growth in the animal models. The proposed treatment strategy may provide a functional pathway for the targeted combined photothermal/photodynamic lung cancer therapy.

An erythrocyte membrance-camouflaged biomimetic nanoplatform for enhanced chemo-photothermal therapy of breast cancer

Nano drug delivery system is a research hotspot in the field of tumor therapy. Molybdenum disulfide (MoS2) nanosheet was selected as the base material and natural red blood cell membrane...

Biomimetic nanoparticles loading with gamabutolin-indomethacin for chemo/photothermal therapy of cervical cancer and anti-inflammation

A pro-nanodrug combinational strategy for efficient cervical cancer therapy with intrinsic tumor microenvironment (TME)-responsive elements and low side effects is highly desired. Here, a pro-nanodrug complexes with GSH and NIR responsive manner is reported to boost gamabufotalin induced chemo-photothermal therapy with the assistance of reprogrammed TME by indomethacin. In addition, hybrid cell membrane was used to endow nanocomplexes with the prolonging circulation time and high accumulation of drug at tumor tissue. Indomethacin activated by the high level GSH can attenuate tumor inflammation microenvironment triggered by PTT and sensitize tumor cells to gamabufotalin through inhibiting PGE2 secretion. The released low-dose gamabufotalin with low side effects can efficiently kill tumor cells by ROS production and COX-2 low expression. In vitro and in vivo assays demonstrated that strong anti-tumor activity of nanocomplexes in tumor-bearing mice through chemo-photothermal therapy, which was reflected by the eradication of cervical tumor and significant extension of survival time of mice.

Optimization of Nanoparticles for Smart Drug Delivery: A Review

Nanoparticle delivery systems have good application prospects in the treatment of various diseases, especially in cancer treatment. The effect of drug delivery is regulated by the properties of nanoparticles. There have been many studies focusing on optimizing the structure of nanoparticles in recent years, and a series of achievements have been made. This review summarizes the optimization strategies of nanoparticles from three aspects-improving biocompatibility, increasing the targeting efficiency of nanoparticles, and improving the drug loading rate of nanoparticles-aiming to provide some theoretical reference for the subsequent drug delivery of nanoparticles.