Ultrasound-propelled nanomotors for efficient cancer cell ferroptosis

Ferroptosis is a non-apoptotic form of cell death that is dependent on the accumulation of intracellular iron that causes elevation of toxic lipid peroxides. Therefore, it is crucial to improve the levels of intracellular iron and reactive oxygen species (ROS) in a short time. Here, we first propose ultrasound (US)-propelled Janus nanomotors (Au-FeOx/PEI/ICG, AFPI NMs) to accelerate cellular internalization and induce cancer cell ferroptosis. This nanomotor consists of a gold-iron oxide rod-like Janus nanomotor (Au-FeOx, AF NMs) and a photoactive indocyanine green (ICG) dye on the surface. It not only exhibits accelerating cellular internalization (∼4-fold) caused by its attractive US-driven propulsion but also shows good intracellular motion behavior. In addition, this Janus nanomotor shows excellent intracellular ROS generation performance due to the synergistic effect of the "Fenton or Fenton-like reaction" and the "photochemical reaction". As a result, the killing efficiency of actively moving nanomotors on cancer cells is 88% higher than that of stationary nanomotors. Unlike previous passive strategies, this work is a significant step toward accelerating cellular internalization and inducing cancer-cell ferroptosis in an active way. These novel US-propelled Janus nanomotors with strong propulsion, efficient cellular internalization and excellent ROS generation are suitable as a novel cell biology research tool.

Influence of PEGylation on WS2 Nanosheets and Its Application in Photothermal Therapy

Photothermal therapy (PTT) is an alternative cancer therapy with minimal side effects and higher efficiency and selectivity. In this study, WS2 nanosheets were developed by ultrasonic exfoliation with different ratios of polyethylene glycol (PEG), and their effects on physicochemical properties were studied. The utilization of PEG during sonication significantly influenced the size and thickness of the resulting WS2 nanosheet layers, which was confirmed through scanning electron microscopy, atomic force microscopy, and dynamic light scattering analyses. PEG functionalization also improved the dispersibility of WS2 in aqueous solution by making its surface hydrophilic, which resulted in better biocompatibility. The intrinsic near-infrared absorbance of the nanosheets positions them as valuable agents for PTT. The study further explores the efficacy of these nanosheets as photothermal agents in the ablation of MDAMB-231 breast cancer cells. Although the use of PEG to demonstrate exfoliation and biocompatibility for WS2 has been reported previously, the effect of PEGylation on various physicochemical properties has not been studied in-depth until now. This study paves the way for the use of highly versatile PEG across a range of 2D material systems.

Combination cancer imaging and phototherapy mediated by membrane-wrapped nanoparticles

Cancer is a devastating health problem with inadequate treatment options. Many conventional treatments for solid-tumor cancers lack tumor specificity, which results in low efficacy and off-target damage to healthy tissues. Nanoparticle (NP)-mediated photothermal therapy (PTT) is a promising minimally invasive treatment for solid-tumor cancers that has entered clinical trials. Traditionally, NPs used for PTT are coated with passivating agents and/or targeting ligands, but alternative coatings are being explored to enhance tumor specific delivery. In particular, cell-derived membranes have emerged as promising coatings that improve the biointerfacing of photoactive NPs, which reduces their immune recognition, prolongs their systemic circulation and increases their tumor accumulation, allowing for more effective PTT. To maximize treatment success, membrane-wrapped nanoparticles (MWNPs) that enable dual tumor imaging and PTT are being explored. These multifunctional theranostic NPs can be used to enhance tumor detection and/or ensure a sufficient quantity of NPs that have arrived in the tumor prior to laser irradiation. This review summarizes the current state-of-the-art in engineering MWNPs for combination cancer imaging and PTT and discusses considerations for the path toward clinical translation.

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.

Microenvironment Restruction of Emerging 2D Materials and their Roles in Therapeutic and Diagnostic Nano-Bio-Platforms

Engineering advanced therapeutic and diagnostic nano-bio-platforms (NBPFs) have emerged as rapidly-developed pathways against a wide range of challenges in antitumor, antipathogen, tissue regeneration, bioimaging, and biosensing applications. Emerged 2D materials have attracted extensive scientific interest as fundamental building blocks or nanostructures among material scientists, chemists, biologists, and doctors due to their advantageous physicochemical and biological properties. This timely review provides a comprehensive summary of creating advanced NBPFs via emerging 2D materials (2D-NBPFs) with unique insights into the corresponding molecularly restructured microenvironments and biofunctionalities. First, it is focused on an up-to-date overview of the synthetic strategies for designing 2D-NBPFs with a cross-comparison of their advantages and disadvantages. After that, the recent key achievements are summarized in tuning the biofunctionalities of 2D-NBPFs via molecularly programmed microenvironments, including physiological stability, biocompatibility, bio-adhesiveness, specific binding to pathogens, broad-spectrum pathogen inhibitors, stimuli-responsive systems, and enzyme-mimetics. Moreover, the representative therapeutic and diagnostic applications of 2D-NBPFs are also discussed with detailed disclosure of their critical design principles and parameters. Finally, current challenges and future research directions are also discussed. Overall, this review will provide cutting-edge and multidisciplinary guidance for accelerating future developments and therapeutic/diagnostic applications of 2D-NBPFs.

Gold Nanoblackbodies-based Multifunctional Nanocomposite for Multimodal Cancer Therapy

Multifunctional nanocomposites are of potential use to achieve complete tumor elimination and, thus, to avoid tumor recurrence. Herein, polydopamine (PDA)-based gold nanoblackbodies (AuNBs) loaded with indocyanine green (ICG) and Doxorubicin (DOX) termed as A-P-I-D nanocomposite were investigated for multimodal plasmonic photothermal-photodynamic-chemotherapy. Upon near-infrared (NIR) irradiation, A-P-I-D nanocomposite showed enhanced photothermal conversion efficiency of 69.2% compared to bare AuNBs (62.9%) due to the presence of ICG, along with ROS (¹O₂) generation as well as enhanced DOX release. On assessment of therapeutic effects on breast cancer (MCF-7) and melanoma (B16F10) cell lines, A-P-I-D nanocomposite showed significantly lower cell viabilities of 45.5% and 24% compared to 79.3% and 76.8% for AuNBs. Fluorescence images of stained cells revealed characteristic signs of apoptotic mode of cell death, with almost complete damage on A-P-I-D nanocomposite+NIR treated cells. Further, on evaluation of photothermal performance through breast tumor-tissue mimicking phantoms, A-P-I-D nanocomposite provided required thermal ablation temperatures within the tumor along with the potential for the elimination of residual cancerous cells through photodynamic therapy and chemotherapy. Overall, this study demonstrates that A-P-I-D nanocomposite+NIR provides better therapeutic outcome on cell lines and enhanced photothermal performance on breast tumor-tissue mimicking phantoms to be a promising agent for multimodal cancer therapy.

Biomimetic graphene oxide quantum dots nanoparticles targeted photothermal-chemotherapy for gastric cancer

Direct use of chemotherapy drugs in the treatment of gastric cancer often leads to systemic side effects and unsatisfied therapeutic efficacy due to the lack of tumour-targeting ability. The excellent properties of nanoparticles make them good tools to provide more options for the targeted delivery of chemotherapeutic drugs. Herein, we developed a novel nanomedicine (GOQD-ICG-CS-6@HM nanoparticles, GIC@HM NPs), which employed graphene oxide quantum dots (GOQDs) to co-load photosensitizer indocyanine green (ICG) and chemotherapeutic drug gamabufotalin (CS-6) as the core and wrapped with the hybrid membrane (erythrocyte membrane and gastric cancer cell membrane, HM) on its surface. This nanomedicine possesses the functions of photothermal therapy and chemotherapy, making it a good choice for the treatment of gastric cancer. The results showed that the bionic-coated hybrid membrane not only improves the biocompatibility of the nanomedicine, and prolong its circulating half-life, but also delivers the drug to the tumour site precisely and improves the efficiency of drug utilisation. In vitro and in vivo studies further showed that GIC@HM NPs exhibited combinational effects on tumour therapy while displaying no obvious side effects on normal tissue. To sum up, the newly developed GIC@HM NPs provide a safer, more efficient, and more precise method for gastric cancer treatment.

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.

Membrane-wrapped nanoparticles for nucleic acid delivery

There is an unmet need for carriers that can deliver nucleic acids (NAs) to cancer cells and tumors to perpetuate gene regulation and manage disease progression. Membrane-wrapped nanoparticles (NPs) can be loaded with exogenously designed nucleic acid cargoes, such as plasmid deoxyribonucleic acid (pDNA), messenger ribonucleic acid (mRNA), small interfering RNA (siRNA), microRNA (miRNA), and immunostimulatory CpG oligodeoxynucleotides (CpG ODNs), to mitigate challenges presented by NAs' undesirable negative charge, hydrophilicity, and relatively large size. By conjugating or encapsulating NAs within membrane-wrapped NPs, various physiological barriers can be overcome so that NAs experience increased blood circulation half-lives and enhanced accumulation in intended sites. This review discusses the status of membrane-wrapped NPs as NA delivery vehicles and their advancement in gene regulation for cancer management in vitro and in vivo. With continued development, membrane-wrapped NPs have great potential as future clinical tools to treat cancer and other diseases with a known genetic basis.

Understanding the bidirectional interactions between two-dimensional materials, microorganisms, and the immune system

Two-dimensional (2D) materials such as the graphene-based materials, transition metal dichalcogenides, transition metal carbides and nitrides (MXenes), black phosphorus, hexagonal boron nitride, and others have attracted considerable attention due to their unique physicochemical properties. This is true not least in the field of medicine. Understanding the interactions between 2D materials and the immune system is therefore of paramount importance. Furthermore, emerging evidence suggests that 2D materials may interact with microorganisms - pathogens as well as commensal bacteria that dwell in and on our body. We discuss the interplay between 2D materials, the immune system, and the microbial world in order to bring a systems perspective to bear on the biological interactions of 2D materials. The use of 2D materials as vectors for drug delivery and as immune adjuvants in tumor vaccines, and 2D materials to counteract inflammation and promote tissue regeneration, are explored. The bio-corona formation on and biodegradation of 2D materials, and the reciprocal interactions between 2D materials and microorganisms, are also highlighted. Finally, we consider the future challenges pertaining to the biomedical applications of various classes of 2D materials.

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.

Multifunctional nanoparticles of sinomenine hydrochloride for treat-to-target therapy of rheumatoid arthritis via modulation of proinflammatory cytokines

Sinomenine is a bioactive alkaloid isolated from the Chinese medicinal plant of Sinomenium acutum (Thunb.) Rehd.et Wils. Currently, sinomenine hydrochloride (SIN) preparations, classified as a natural disease-modifying anti-rheumatic drug (nDMARD), have been used for therapy of rheumatoid arthritis (RA); however, the efficacy of SIN was seriously limited by its short half-life, low bioavailability, and dose-dependent adverse reactions. In this study, a biomimetic nanocomplex based on Prussian blue nanoparticles (PB NPs) was developed for overcoming clinical limitations of SIN and accordingly improving its efficacy. In vitro studies showed that the nanocomplexes significantly inhibited abnormal proliferation of fibroblast-like synoviocytes (FLSs) by scavenging reactive oxygen species (ROS) and inhibiting secretion of proinflammatory cytokines. In vivo imaging demonstrated that the improved immune-escape properties of the nanocomplexes resulted in markedly increased half-life of circulation and levels of accumulated drugs at arthritic sites of adjuvant-induced arthritis (AIA) rats. Notably, the nanocomplexes significantly suppressed joint inflammation and protected against bone destruction of AIA rats by inhibiting inflammatory cytokine secretion of the synovial macrophages and FLSs. These results indicate that the nanocomplexes provide an excellent carrier for controlled release and targeted accumulation of SIN within the arthritic sites, which consequently achieve disease-remitting effects of SIN on RA.

Recent Advances in Transition-Metal Based Nanomaterials for Noninvasive Oncology Thermal Ablation and Imaging Diagnosis

With the developments of nanobiotechnology and nanomedicine, non-invasive thermal ablation with fewer side effects than traditional tumor treatment methods has received extensive attention in tumor treatment. Non-invasive thermal ablation has the advantages of non-invasiveness and fewer side effects compared with traditional treatment methods. However, the clinical efficiency and biological safety are low, which limits their clinical application. Transition-metal based nanomaterials as contrast agents have aroused increasing interest due to its unique optical properties, low toxicity, and high potentials in tumor diagnosis. Transition-metal based nanomaterials have high conversion efficiency of converting light energy into heat energy, good near-infrared absorption characteristics, which also can targetedly deliver those loaded drugs to tumor tissue, thereby improving the therapeutic effect and reducing the damage to the surrounding normal tissues and organs. This article mainly reviews the synthesis of transition-metal based nanomaterials in recent years, and discussed their applications in tumor thermal ablation and diagnosis, hopefully guiding the development of new transition metal-based nanomaterials in enhancing thermal ablation.

2D Nanosheets-A New Class of Therapeutic Formulations against Cancer

Researchers in cancer nanomedicine are exploring a revolutionary multifaceted carrier for treatment and diagnosis, resulting in the proposal of various drug cargos or "magic bullets" in this past decade. Even though different nano-based complexes are registered for clinical trials, very few products enter the final stages each year because of various issues. This prevents the formulations from entering the market and being accessible to patients. In the search for novel materials, the exploitation of 2D nanosheets, including but not limited to the highly acclaimed graphene, has created extensive interest for biomedical applications. A unique set of properties often characterize 2D materials, including semiconductivity, high surface area, and their chemical nature, which allow simple decoration and functionalization procedures, structures with high stability and targeting properties, vectors for controlled and sustained release of drugs, and materials for thermal-based therapies. This review discusses the challenges and opportunities of recently discovered 2D nanosheets for cancer therapeutics, with special attention paid to the most promising design technologies and their potential for clinical translation in the future.

Novel nanomedicines to overcome cancer multidrug resistance

Chemotherapy remains a powerful tool to eliminate malignant cells. However, the efficacy of chemotherapy is compromised by the frequent emergence of intrinsic and acquired multidrug resistance (MDR). These chemoresistance modalities are based on a multiplicity of molecular mechanisms of drug resistance, including : 1) Impaired drug uptake into cancer cells; 2) Increased expression of ATP-binding cassette efflux transporters; 3) Loss of function of pro-apoptotic factors; 4) Enhanced DNA repair capacity; 5) Qualitative or quantitative alterations of specific cellular targets; 6) Alterations that allow cancer cells to tolerate adverse or stressful conditions; 7) Increased biotransformation or metabolism of anticancer drugs to less active or completely inactive metabolites; and 8) Intracellular and intercellular drug sequestration in well-defined organelles away from the cellular target. Hence, one of the major aims of cancer research is to develop novel strategies to overcome cancer drug resistance. Over the last decades, nanomedicine, which focuses on targeted delivery of therapeutic drugs into tumor tissues using nano-sized formulations, has emerged as a promising tool for cancer treatment. Therefore, nanomedicine has been introduced as a reliable approach to improve treatment efficacy and minimize detrimental adverse effects as well as overcome cancer drug resistance. With rationally designed strategies including passively targeted delivery, actively targeted delivery, delivery of multidrug combinations, as well as multimodal combination therapy, nanomedicine paves the way towards efficacious cancer treatment and hold great promise in overcoming cancer drug resistance. Herein, we review the recent progress of nanomaterials used in medicine, including liposomal nanoparticles, polymeric nanoparticles, inorganic nanoparticles and hybrid nanoparticles, to surmount cancer multidrug resistance. Finally, the future perspectives of the application of nanomedicine to reverse cancer drug resistance will be addressed.

A hybrid membrane coating nanodrug system against gastric cancer via the VEGFR2/STAT3 signaling pathway

Although drug combination has proved to be an efficient strategy for clinic gastric cancer therapy, how to further improve their bioavailability and reduce the side effects are still challenges due to the low solubility and untargeted ability of drugs. Recently, newly emerging nanotechnology has provided an alternative for constructing new drug delivery systems with high targeting ability and solubility. In this study, a pH-responsive liposome (Liposome-PEO, LP) loaded with apatinib (AP) and cinobufagin (CS-1) was used for combinational therapy against gastric cancer after coating with a hybrid membrane (R/C). The results indicated that the constructed nanocomplex LP-R/C@AC not only efficiently killed tumor cells in vitro by inducing apoptosis, autophagy, and pyroptosis, but also significantly inhibited tumor invasion and metastasis via the VEGFR2/STAT3 pathway. Moreover, it showed stronger anti-tumor activity in gastric cancer-bearing mouse models, as compared to the sole drugs. A naturally-derived hybrid cell membrane coating bestowed nanocomplexes with enhanced biointerfacing including prolonged circulation time and targeting ability.

Polymer encapsulated clinical ICG nanoparticles for enhanced photothermal therapy and NIR fluorescence imaging in cervical cancer

Photothermal therapy (PTT) is a popular tumor therapy method, which is based on efficient photothermal nanoagents (PTNs). Clinical Indocyanine Green (ICG), as a Food and Drug Administration (FDA) approved agent, is an often-used PTN, meanwhile it is also a good near-infrared (NIR) fluorescence contrast agent. However, the further applications of ICG in biomedical fields are limited due to its poor stability. In this study, ICG was encapsulated by the amphiphilic polymer poly(styrene-co-maleic anhydride) (PSMA) to form ICG@PSMA nanoparticles. Furthermore, optical and thermal characteristics of ICG@PSMA nanoparticles were studied in detail. Strong NIR fluorescence and excellent photothermal properties of ICG@PSMA nanoparticles under 808 nm laser irradiation were measured. Besides, favorable biocompatibility of ICG@PSMA nanoparticles was demonstrated on a human cervical cancer cell line (HeLa) via cell viability studies. Hence, ICG@PSMA nanoparticles were further applied to enhanced PTT of living HeLa cells under 808 nm excitation, and a high PTT efficiency of ∼70% was obtained. The novel ICG nanoparticles as a promising PTT nanoplatform could offer an opportunity for further tumour treatments.

PSMA encapsulated Clinical ICG to form ICG@PSMA nanoparticles. ICG@PSMA nanoparticles showed strong NIR fluorescence and excellent photothermal properties.

Biomimetic Nanoscale Erythrocyte Delivery System for Enhancing Chemotherapy via Overcoming Biological Barriers

Overcoming multiple biological barriers, including circulation time in vivo, tumor vascular endothelium, reticuloendothelial system (RES), extracellular matrix (ECM), etc., is the key to improve the therapeutic efficacy of drug delivery systems in treating tumors. Inspired by the ability of natural erythrocytes to cross multiple barriers, in this study, a biomimetic delivery system named NE@DOX-Ang2 was developed for enhancing the chemotherapy of breast cancer, which employed nano-erythrocyte (NE) encapsulating doxorubicin (DOX) and surface modification with a targeted angiopep-2 peptide (Ang2). NE@DOX-Ang2 enhanced the capacity to cross biological barriers in a three-dimensional (3D) tumor spheroid model and in vivo in mice. Compared with a conventional drug delivery system of liposomes, the half-life of NE@DOX-Ang2 increased approximately 2.5 times. Moreover, NE@DOX-Ang2 exhibited excellent tumor-targeting ability and antitumor effects in vitro and in vivo. Briefly, the prepared nano-erythrocyte drug carrier has features of favorable biocompatibility and low immunogenicity and the advantage of prolonging the half-life of drugs, which may provide a novel perspective for development of clinically available nanomedicines.

Nanocarrier-Based Drug Delivery for Melanoma Therapeutics

Melanoma, as a tumor cell derived from melanocyte transformation, has the characteristics of malignant proliferation, high metastasis, rapid recurrence, and a low survival rate. Traditional therapy has many shortcomings, including drug side effects and poor patient compliance, and so on. Therefore, the development of an effective treatment is necessary. Currently, nanotechnologies are a promising oncology treatment strategy because of their ability to effectively deliver drugs and other bioactive molecules to targeted tissues with low toxicity, thereby improving the clinical efficacy of cancer therapy. In this review, the application of nanotechnology in the treatment of melanoma is reviewed and discussed. First, the pathogenesis and molecular targets of melanoma are elucidated, and the current clinical treatment strategies and deficiencies of melanoma are then introduced. Following this, we discuss the main features of developing efficient nanosystems and introduce the latest reports in the literature on nanoparticles for the treatment of melanoma. Subsequently, we review and discuss the application of nanoparticles in chemotherapeutic agents, immunotherapy, mRNA vaccines, and photothermal therapy, as well as the potential of nanotechnology in the early diagnosis of melanoma.

Cell membrane camouflaged bismuth nanoparticles for targeted photothermal therapy of homotypic tumors

Bi nanoparticles (NPs) have been demonstrated as effective all-in-one type theranostic agent for imaging-guided photothermal therapy, but their applications have been limited by relatively low biocompatibility and target accumulation capacity. To address this issue, we report the camouflage of Bi NPs (size: ~42 ± 2 nm) by using the mouse colon cancer CT26 cells membrane (CT26 CCM). The camouflaging process confers the efficient coating of CCM shell layer with thickness of ~8 ± 2 nm on Bi NPs cores, which can be confirmed by TEM image, zeta potential and protein gel electrophoresis tests. Simultaneously, CCM shell has no side effects on the photoabsorption/photothermal effect. Importantly, Bi@CCM NPs retain significant features of CCM, including good biocompatibility and homologous targeting ability. When Bi@CCM dispersion was intravenously (i.v.) injected into mice, they exhibited higher blood circulation half-life (11.5 h, ~2.9 times) and accumulation amount (4.7 ± 0.56% ID/g, ~2.3 times) in homotypic CT26 tumor compared to those (4.0 h in blood and 2.03 ± 0.60% ID/g in tumor) from uncoated Bi NPs. After 808 nm laser irradiation, CT26 cancer cells could be effectively ablated after the photothermal therapy of high-accumulated Bi@CCM NPs, and then the tumor tends to be eradicated after 12 days. Thus, Bi NPs camouflaged with CT26 CCM have great potential for the targeted photothermal therapy of homotypic tumors.