Inorganic Nanocarriers Overcoming Multidrug Resistance for Cancer Theranostics

Potent in vitro activity of curcumin and quercetin co-encapsulated in nanovesicles without hyaluronan against Aspergillus and Candida isolates

The rapid emergence of resistance to classical antifungals has increased the interest in novel antifungal compounds. Curcumin and quercetin are two natural plant-derived bioactive molecules shown to promote wound healing in injured tissues. In this study, we investigated the in vitro susceptibility of several Aspergillus and Candida isolates to curcumin and quercetin encapsulated in nanovesicles with and without hyaluronan and elucidated the efficacy of these nanovesicles as topical drug delivery systems. Antifungal susceptibility testing performed according to the CLSI guidelines indicated that curcumin-quercetin co-encapsulated in nanovesicles without hyaluronan (CUR-QUE-NV-WH) had stronger activity against Candida isolates than fluconazole. Furthermore, CUR-QUE-NV-WH showed efficacy against fluconazole-resistant Candida isolates as evidenced by MICs at least two times lower than those of fluconazole. Examination of skin permeation profiles using an in vitro Franz diffusion cell system revealed that curcumin and quercetin delivered by nanovesicles were released and accumulated in the skin; however, only quercetin could penetrate through the skin layers. Collectively, our results demonstrate that CUR-QUE-NV-WH has potent antifungal activity against Candida isolates and might be a topical treatment, which warrants its further investigation as a novel antifungal agent.

Biodegradable photoresponsive nanoparticles for chemo-, photothermal- and photodynamic therapy of ovarian cancer

Ovarian cancer (OC) is the deadliest gynecological cancer. Standard treatment of OC is based on cytoreductive surgery followed by chemotherapy with platinum drugs and taxanes; however, innate and acquired drug-resistance is frequently observed followed by a relapse after treatment, thus, more efficient therapeutic approaches are required. Combination therapies involving phototherapies and chemotherapy (the so-called chemophototherapy) may have enhanced efficacy against cancer, by attacking cancer cells through different mechanisms, including DNA-damage and thermally driven cell membrane and cytoskeleton damage. We have designed and synthesized poly(lactic-co-glycolic) nanoparticles (PLGA NPs) containing the chemo-drug carboplatin (CP), and the near infrared (NIR) photosensitizer indocyanine green (ICG). We have evaluated the drug release profile, the photodynamic ROS generation and photothermal capacities of the NPs. Also, the antitumoral efficiency of the NPs was evaluated using the SKOV-3 cell line as an in vitro OC model, observing an enhanced cytotoxic effect when irradiating cells with an 800 nm laser. Evidence here shown supports the potential application of the biodegradable photoresponsive NPs in the clinical stage due to the biocompatibility of the materials used, the spatiotemporal control of the therapy and, also, the less likely development of resistance against the combinatorial therapy.

Ligand-Installed Nanocarriers toward Precision Therapy

Development of drug-delivery systems that selectively target neoplastic cells has been a major goal of nanomedicine. One major strategy for achieving this milestone is to install ligands on the surface of nanocarriers to enhance delivery to target tissues, as well as to enhance internalization of nanocarriers by target cells, which improves accuracy, efficacy, and ultimately enhances patient outcomes. Herein, recent advances regarding the development of ligand-installed nanocarriers are introduced and the effect of their design on biological performance is discussed. Besides academic achievements, progress on ligand-installed nanocarriers in clinical trials is presented, along with the challenges faced by these formulations. Lastly, the future perspectives of ligand-installed nanocarriers are discussed, with particular emphasis on their potential for emerging precision therapies.

Nanocarriers for the Delivery of Medical, Veterinary, and Agricultural Active Ingredients

Nanocarrier-based delivery systems can be used to increase the safety and efficacy of active ingredients in medical, veterinary, or agricultural applications, particularly when such ingredients are unstable, sparingly soluble, or cause off-target effects. In this review, we highlight the diversity of nanocarrier materials and their key advantages compared to free active ingredients. We discuss current trends based on peer-reviewed research articles, patent applications, clinical trials, and the nanocarrier formulations already approved by regulatory bodies. Although most nanocarriers have been engineered to combat cancer, the number of formulations developed for other purposes is growing rapidly, especially those for the treatment of infectious diseases and parasites affecting humans, livestock, and companion animals. The regulation and prohibition of many pesticides have also fueled research to develop targeted pesticide delivery systems based on nanocarriers, which maximize efficacy while minimizing the environmental impact of agrochemicals.

Endosome/lysosome-detained supramolecular nanogels as an efflux retarder and autophagy inhibitor for repeated photodynamic therapy of multidrug-resistant cancer

The presence of drug efflux pumps and endo/lysosomal entrapment phenomena in multidrug-resistant cancer cells leads to insufficient and off-target accumulation of anticancer drugs in the cells, which severely reduces the drugs' therapeutic efficacies. Here, we prepare a novel type of photosensitizer (PS)-loaded supramolecular nanogel, which can utilize the endo/lysosomal entrapment for enhanced photodynamic therapy (PDT) of multidrug-resistant cancer. The PS-loaded nanogels can elude the drug efflux pumps, and be markedly internalized by drug-resistant cancer cells through the endocytic pathway. With their pH-sensitive properties, the internalized nanogels can aggregate in the acidic endosomes/lysosomes, thus retarding their exocytosis from the cells. Moreover, the lysosomes of the nanogel-treated cells are severely damaged after irradiation, which inhibits the protective autophagy and improves the photodynamic therapeutic performance of the nanogels. Besides, the in vivo experiments show that the nanogels significantly prolong the tumor retention of the PSs, thus enabling multiple PDT treatments after a single drug injection.

RNA Nanotechnology-Mediated Cancer Immunotherapy

RNA molecules (e.g., siRNA, microRNA, and mRNA) have shown tremendous potential for immunomodulation and cancer immunotherapy. They can activate both innate and adaptive immune system responses by silencing or upregulating immune-relevant genes. In addition, mRNA-based vaccines have recently been actively pursued and tested in cancer patients, as a form of treatment. Meanwhile, various nanomaterials have been developed to enhance RNA delivery to the tumor and immune cells. In this review article, we summarize recent advances in the development of RNA-based therapeutics and their applications in cancer immunotherapy. We also highlight the variety of nanoparticle platforms that have been used for RNA delivery to elicit anti-tumor immune responses. Finally, we provide our perspectives of potential challenges and opportunities of RNA-based nanotherapeutics in clinical translation towards cancer immunotherapy.

Towards early monitoring of chemotherapy-induced drug resistance based on single cell metabolomics: Combining single-probe mass spectrometry with machine learning

Despite the presence of methods evaluating drug resistance during chemotherapies, techniques, which allow for monitoring the degree of drug resistance in early chemotherapeutic stage from single cells in their native microenvironment, are still absent. Herein, we report an analytical approach that combines single cell mass spectrometry (SCMS) based metabolomics with machine learning (ML) models to address the existing challenges. Metabolomic profiles of live cancer cells (HCT-116) with different levels (i.e., no, low, and high) of chemotherapy-induced drug resistance were measured using the Single-probe SCMS technique. A series of ML models, including random forest (RF), artificial neural network (ANN), and penalized logistic regression (LR), were constructed to predict the degrees of drug resistance of individual cells. A systematic comparison of performance was conducted among multiple models, and the method validation was carried out experimentally. Our results indicate that these ML models, especially the RF model constructed on the obtained SCMS datasets, can rapidly and accurately predict different degrees of drug resistance of live single cells. With such rapid and reliable assessment of drug resistance demonstrated at the single cell level, our method can be potentially employed to evaluate chemotherapeutic efficacy in the clinic.

Photodynamic effect of Zirconium phosphate biocompatible nano-bilayers containing methylene blue on cancer and normal cells

Pharmaceutical applications of methylene blue, especially as photosensitizer, have been limited due to its rapid enzymatic reduction in the biological systems. In this study nano-platelet zirconium phosphate was synthesized and its biocompatibility was evaluated. The synthesized material was considered as drug delivery vehicle for methylene blue to enhance the photodynamic therapy efficacy in human breast cancer cells. Zirconium phosphate-methylene blue nano-hybrids were characterized by X-Ray Powder Diffraction (XRPD), Scanning Electron Microscopy (SEM), and Thermo gravimetric Analysis (TGA). Biocompatibility of synthesized nano materials were studied on Hu02 human fibroblast normal cell and MDA-MB-231 human breast cancer cell. The results clarified that ZrP-MB nanoparticles could decrease the dark toxicity of free methylene blue. Photodynamic therapy using zirconium phosphate-methylene blue on MDA-MB-231 human breast cancer was evaluated by MTT assay, colony forming ability assay, AO/EB dual staining and flow cytometry detection of apoptosis. The results suggest that zirconium phosphate-methylene blue nano-hybrids significantly enhance photodynamic therapy efficacy probably via apoptosis cell death mechanism against human breast cancer cells. According to the results, zirconium phosphate nanoparticles could be suggested as a promising nano-carrier for photosensitizer delivery in photodynamic therapy.

Genetically Engineered Plasma Membrane Nanovesicles for Cancer-Targeted Nanotheranostics

A series of ligand-targeted nanosystems have been rapidly exploited to selectively deliver drug molecules to desired cell populations. The conjugation of protein ligands to the nanoparticle (NP) surface endows nanovehicles with active targeting properties. However, the nonspecific covalent coupling of protein ligands to nanocarriers may compromise the protein targeting due to the uncontrolled ligand orientation as well as the decline in ligand activity during linkage process. With this regard, biomimetic synthetic strategies are employed for the preparation of genetically engineered nanovesicles (GNV) from cellular plasma membrane with targeting moieties on the surface in a ligand-oriented manner. Herein, we introduce the biomimetic synthetic strategy and procedures for GNV preparation. This chapter may guide readers to design analogous NPs for cell-specific targeting by displaying particular protein probes (e.g., antibody, nanobody, and single-chain antibody) on the surface of GNVs.

Calcium phosphate nanocarriers for drug delivery to tumors: imaging, therapy and theranostics

Calcium phosphate (CaP) was engineered as a drug delivery nanocarrier nearly 50 years ago due to its biocompatibility and biodegradability. In recent years, several approaches have been developed for the preparation of size-controllable, stable and multifunctional CaP nanocarriers, and several targeting moieties have also been decorated on the surface of these nanocarriers for active targeting. The CaP nanocarriers have been utilized for loading probes, nucleic acids, anticancer drugs and photosensitizers for cancer imaging, therapy and theranostics. Herein, we reviewed the recent advances in the preparation strategies of CaP nanocarriers and the applications of these nanocarriers in tumor diagnosis, gene delivery, drug delivery and theranostics and finally provided perspectives.

Stimuli-responsive nanodrug self-assembled from amphiphilic drug-inhibitor conjugate for overcoming multidrug resistance in cancer treatment

Severe multidrug resistance (MDR) often develops in the process of chemotherapy for most small molecule anticancer drugs, which results in clinical chemotherapy failures.

Methods: Here, a nanodrug is constructed through the self-assembly of amphiphilic drug-inhibitor conjugates (ADIC) containing a redox-responsive linkage for reversing the multidrug resistance (MDR) in cancer treatment. Specifically, hydrophilic anticancer irinotecan (Ir) and hydrophobic P-gp protein inhibitor quinine (Qu) are linked by a redox responsive bridge for overcoming MDR of tumors.

Results: Ir-ss-Qu is able to self-assemble into nanoparticles (NPs) in water and shows the longer blood retention half-life compared with that of free Ir or Qu, which facilitates drug accumulation in tumor site. After endocytosis of Ir-ss-Qu NPs by drug-resistant tumor cells, the disulfide bond in the linkage between Ir and Qu is cleaved rapidly induced by glutathione (GSH) to release anticancer drug Ir and inhibitor Qu synchronously. The released Qu can markedly reduce the expression of P-gp in drug-resistant tumor cells and inhibits P-gp to pump Ir out of the cells. The increased concentration of intracellular Ir can effectively improve the therapeutic efficacy.

Conclusions: Such redox-responsive Ir-ss-Qu NPs, as a drug delivery system, exhibit very high cytotoxicity and the most effective inhibitory to the growth of drug-resistant breast cancer compared with that of free therapeutic agents in vitro and in vivo.

Molecular Targeting-Mediated Mild-Temperature Photothermal Therapy with a Smart Albumin-Based Nanodrug

Photothermal therapy (PTT) usually requires hyperthermia >50 °C for effective tumor ablation, which inevitably induces heating damage to the surrounding normal tissues/organs. Moreover, low tumor retention and high liver accumulation are the two main obstacles that significantly limit the efficacy and safety of many nanomedicines. To solve these problems, a smart albumin-based tumor microenvironment-responsive nanoagent is designed via the self-assembly of human serum albumin (HSA), dc-IR825 (a cyanine dye and a photothermal agent), and gambogic acid (GA, a heat shock protein 90 (HSP90) inhibitor and an anticancer agent) to realize molecular targeting-mediated mild-temperature PTT. The formed HSA/dc-IR825/GA nanoparticles (NPs) can escape from mitochondria to the cytosol through mitochondrial disruption under near-infrared (NIR) laser irradiation. Moreover, the GA molecules block the hyperthermia-induced overexpression of HSP90, achieving the reduced thermoresistance of tumor cells and effective PTT at a mild temperature (<45 °C). Furthermore, HSA/dc-IR825/GA NPs show pH-responsive charge reversal, effective tumor accumulation, and negligible liver deposition, ultimately facilitating synergistic mild-temperature PTT and chemotherapy. Taken together, the NIR-activated NPs allow the release of molecular drugs more precisely, ablate tumors more effectively, and inhibit cancer metastasis more persistently, which will advance the development of novel mild-temperature PTT-based combination strategies.

Method for the Instant In-Flight Manufacture of Black Phosphorus to Assemble Core@Shell Nanocomposites for Targeted Photoimmunotherapy

Inorganic nanomaterial (INM)-based combination cancer therapies have been extensively employed over the past two decades because of their benefits over traditional chemo- and radiotherapies. However, issues regarding the toxicity and accumulation of INMs in the body have arisen. This problem may be improved through the use of biodegradable or disintegrable nanosystems such as black phosphorus (BP). Challenges to the manufacture of fully nanodimensional BP remain. In addition, improvements in recently developed cancer immunotherapies require their incorporation with drugs, targeting agents, and delivery vehicles. With these needs in mind, this study develops a method for instant in-flight manufacture of nanodimensional BP using plug-and-play devices for subsequent assembly of photoimmunotherapeutic core@shell composites containing mutated B-raf inhibitors (dabrafenib), immune checkpoint inhibitors (PD-L1), and cancer-targeting antibodies (CXCR4). The resulting nanocomposites exhibited cancer targetability and regulatability of PD-L1 expression both in vitro and in vivo. These activities were further increased upon near-infrared irradiation due to the incorporation of a phototherapeutic component. These results suggest that these nanocomposites are promising as a new class of advanced cancer therapeutic agents.

Environmentally responsive dual-targeting nanotheranostics for overcoming cancer multidrug resistance

The development of multiple drug resistance (MDR) to chemotherapy and subsequent treatment failures are major obstacles in cancer therapy. An attractive option for combating MDR is inhibiting the expression of P-glycoprotein (P-gp) in tumor cells. Here, we report a novel chemosensitizing agent, XMD8-92, which can down-regulate P-gp. To enhance the specificity of MDR chemotherapy, a promising nanotheranostic micelle system based on poly(ethylene glycol)-blocked-poly(L-leucine) (PEG-b-Leu) was developed to simultaneously carry the anticancer drug doxorubicin, chemosensitizing agent XMD8-92, and superparamagnetic iron oxide nanoparticles (SPIOs). Featured with MDR environmentally responsive dual-targeting capability, controllable drug delivery, and efficient magnetic resonance (MR) imaging characteristics, the prepared nanotheranostics (DXS@NPs) showed outstanding in vitro cytotoxicity on MDR cells (SCG 7901/VCR) with only 53% of cells surviving compared to 90% of DOX-treated cells. Furthermore, efficient tumor inhibition and highly reduced systemic toxicity were exhibited by MDR tumor-bearing mice treated with DXS@NPs. Overall, the environmentally responsive dual-targeting nanotheranostics represent a promising approach for overcoming cancer MDR.

Carbon-Based Nanomaterials for Biomedical Applications: A Recent Study

The study of carbon-based nanomaterials (CBNs) for biomedical applications has attracted great attention due to their unique chemical and physical properties including thermal, mechanical, electrical, optical and structural diversity. With the help of these intrinsic properties, CBNs, including carbon nanotubes (CNT), graphene oxide (GO), and graphene quantum dots (GQDs), have been extensively investigated in biomedical applications. This review summarizes the most recent studies in developing of CBNs for various biomedical applications including bio-sensing, drug delivery and cancer therapy.

An ingenious non-spherical mesoporous silica nanoparticle cargo with curcumin induces mitochondria-mediated apoptosis in breast cancer (MCF-7) cells

Curcumin delivery to cancer cells is challenging due to its hydrophobic nature, low bio distribution and low availability. Many nano vehicles suffer from low stability and toxicity, and hence the prerequisite of a non-toxic nano vehicle with effective drug delivery is still being delved. The present study investigates the delivery efficiency of curcumin with non-spherical mesoporous silica nanoparticles (MSNAs). Their mechanism of drug delivery and signalling proteins activated to induce apoptosis was further explored in MCF-7 cells. A non-spherical MSN was synthesised, functionalised with PEI (MSNAP) and analysed its intracellular behaviour. Our result indicates that MSNAP was non-toxic until 20 µg/mL and likely localizes in cytoplasmic vesicles. On contrast, well-known MCM-41P induced autophagosome formation, indicating cellular toxicity. Curcumin was loaded on MSNAP and its effectiveness in inducing cell death was studied in MCF-7 and in MCF-7R cells. Curcumin loading on MSNAP induces better cell death with 30 µM curcumin, better than unbounded curcumin. Western blot analysis suggest, curcumin induce apoptosis through the activation of caspase 9, 6, 12, PARP, CHOP and PTEN. The cell survival protein Akt1 was downregulated by curcumin with and without the nanostructure. Interestingly, cleaved caspase 9 was activated in higher amount in nano-conjugated curcumin compared to the free curcumin. But other ER resident protein like IRE1α, PERK and GRP78 were downregulated indicating curcumin disturbs ER homeostasis. Further, electron microscopic analysis reveled that nanocurcumin induced apoptosis by disrupting mitochondria and nucleus. Our results with doxorubicin resistant MCF-7 cell lines confirm nanodelivery of doxorubicin and curcumin sensitised cells effectively at lesser concentration. Further docking studies of curcumin indicate it interacts with the apoptotic proteins through hydrogen bonding formation and with higher binding energy.

Vehicle-saving theranostic probes based on hydrophobic iron oxide nanoclusters using doxorubicin as a phase transfer agent for MRI and chemotherapy

A simple approach for constructing vehicle-saving theranostic nanobeads for MRI and chemotherapy is developed by using doxorubicin for phase transfer of iron oxide nanoclusters.

Cationic Silver Nanoclusters as Potent Antimicrobials against Multidrug-Resistant Bacteria

Bacterial multidrug resistance (MDR) is a serious healthcare issue caused by the long-term subtherapeutic clinical treatment of infectious diseases. Nanoscale engineering of metal nanoparticles has great potential to address this issue by tuning the nano-bio interface to target bacteria. Herein, we report the use of branched polyethylenimine-functionalized silver nanoclusters (bPEI-Ag NCs) to selectively kill MDR pathogenic bacteria by combining the antimicrobial activity of silver with the selective toxicity of bPEI toward bacteria. The minimum inhibitory concentration of bPEI-Ag NCs was determined against 12 uropathogenic MDR strains and found to be 10- to 15-fold lower than that of PEI and 2- to 3-fold lower than that of AgNO₃ alone. Cell viability and hemolysis assays demonstrated the biocompatibility of bPEI-Ag NCs with human fibroblasts and red blood cells, with selective toxicity against MDR bacteria.

Photothermally controlled drug release system with high dose loading for synergistic chemo-photothermal therapy of multidrug resistance cancer

Chemotherapy is an important first-line strategy for tumor therapy in cancer treatment, but multidrug resistance (MDR) is a major problem that reduces the efficacy of chemotherapeutics. Herein, we report a novel photothermally controlled intelligent drug release system (AuNP@mSiO₂-DOX-FA) with a large amount of drugs loading for synergistic chemo-photothermal therapy of MDR in breast cancer. The nanoplatform utilized gold nanoparticles as a hyperthermia core, and large-mesoporous silica as a shell for doxorubicin (DOX) loading. Benefiting from the thick layer and large pore size, the encapsulation and loading efficiency were as high as 97.7% and 8.84%, respectively. Furthermore, under the trigger of 808 nm near infrared (NIR) light, the released DOX increased significantly at pH 5.0 and reached to 39.0% in 20 min, achieving a facile intelligent control of chemotherapy additional to the photothermal therapy. The viability of MCF-7/ADR cells could be efficiently reduced to 16.9%, demonstrating the proposed photothermally controlled system with synergistic chemo-photothermal therapy has great potential capability to overcome MDR in breast cancer.

Shape-Controlled Synthesis of Luminescent Hemoglobin Capped Hollow Porous Platinum Nanoclusters and their Application to Catalytic Oxygen Reduction and Cancer Imaging

Engineering hollow and porous platinum nanostructures using biomolecular templates is currently a significant focus for the enhancement of their facet-dependent optical, electronic, and electrocatalytic properties. However, remains a formidable challenge due to lack of appropriate biomolecules to have a structure-function relationship with nanocrystal facet development. Herein, human hemoglobin found to have facet-binding abilities that can control the morphology and optical properties of the platinum nanoclusters (Pt NCs) by regulation of the growth kinetics in alkaline media. Observations revealed the growth of unusual polyhedra by shape-directed nanocluster attachment along a certain orientation accompanied by Ostwald ripening and, in turn, yield well-dispersed hollow single-crystal nanotetrahedrons, which can easily self-aggregated and crystallized into porous and polycrystalline microspheres. The spontaneous, biobased organization of Pt NCs allow the intrinsic aggregation-induced emission (AIE) features in terms of the platinophilic interactions between Pt(II)-Hb complexes on the Pt(0) cores, thereby controlling the degree of aggregation and the luminescent intensity of Pt(0)@Pt(II)−Hb core−shell NCs. The Hb-Pt NCs exhibited high-performance electrocatalytic oxygen reduction providing a fundamental basis for outstanding catalytic enhancement of Hb-Pt catalysts based on morphology dependent and active site concentration for the four-electron reduction of oxygen. The as-prepared Hb-Pt NCs also exhibited high potential to use in cellular labeling and imaging thanks to the excellent photostability, chemical stability, and low cytotoxicity.

Functional probes for cardiovascular molecular imaging

Cardiovascular diseases (CVDs) are a severely threatening disorder and frequently cause death in industrialized countries, posing critical challenges to modern research and medicine. Molecular imaging has been heralded as the solution to many problems encountered in individuals living with CVD. The use of probes in cardiovascular molecular imaging is causing a paradigmatic shift from regular imaging techniques, to future advanced imaging technologies, which will facilitate the acquisition of vital information at the cellular and molecular level. Advanced imaging for CVDs will help early detection of disease development, allow early therapeutic intervention, and facilitate better understanding of fundamental biological processes. To promote a better understanding of cardiovascular molecular imaging, this article summarizes the current developments in the use of molecular probes, highlighting some of the recent advances in probe design, preparation, and functional modification.

An Intravascular Magnetic Catheter Enables the Retrieval of Nanoagents from the Bloodstream

The clinical adoption of nanoscale agents for targeted therapy is still hampered by the quest for a balance between therapy efficacy and side effects on healthy tissues, due to nanoparticle biodistribution and undesired drug accumulation issues. Here, an intravascular catheter able to efficiently retrieve from the bloodstream magnetic nanocarriers not contributing to therapy, thus minimizing their uncontrollable dispersion and consequently attenuating possible side effects, is proposed. The device consists of a miniature module, based on 27 permanent magnets arranged in two coaxial series, integrated into a clinically used 12 French catheter. This device can capture ≈94% and 78% of the unused agents when using as carriers 500 and 250 nm nominal diameter superparamagnetic iron oxide nanoparticles, respectively. This approach paves the way to the exploitation of new "high-risk/high-gain" drug formulations and supports the development of novel therapeutic strategies based on magnetic hyperthermia or magnetic microrobots.

A drug-delivering-drug strategy for combined treatment of metastatic breast cancer

Treatment of metastatic cancer continues to be a huge challenge worldwide. Notably, drug nanocrystals (Ns) in nanosuspensions clearly belong to a type of nanoparticle. Therefore, a question arose as to whether these drug particles can also be applied as carriers for drug delivery. Here, we design a novel paclitaxel (PTX) nanocrystal stabilized with complexes of matrix metalloproteinase (MMP)-sensitive β-casein/marimastat (MATT) for co-delivering MATT and PTX and combined therapy of metastatic breast cancer. The prepared Ns (200 nm) with a drug-loading of >50% were potent in treatment of metastatic cancer, which markedly inhibited MMP expression and activity and greatly blocked the lung metastasis and angiogenesis. In conclusion, employing protein-drug complexes as stabilizers, Ns with dual payloads are developed and are a promising strategy for co-delivery. Furthermore, the developed Ns can target the tumor microenvironment and cancer cells and, as a result, enable efficient treatment for breast metastatic cancer.

HAase-sensitive dual-targeting irinotecan liposomes enhance the therapeutic efficacy of lung cancer in animals

Among all cancers, lung cancer is one of the most common and serious types of cancer. It is challenging for site-specific delivery of anticancer therapeutics to tumor cells. Herein, we developed a novel“smart” dual-targeting liposomal platform to respond to the highly expressed hyaluronidase (HAase) in the tumor microenvironment and improve tumor targeting and antitumor efficacy.

Methods: In our design, the HA was used as a sensitive linker between a liposomal lipid and long chain PEG block to synthesize three functional conjugates in order to prepare“smart” liposomal platform modified with epidermal growth factor receptor (EGFR) antibody (GE11) and cell-penetrating peptide (TATp). Using irinotecan as a model therapeutic, evaluations were performed on the human lung adenocarcinoma A549 cells as well as the xenografted A549 cancer cells in nude mice.

Results: The GE11/HA/TATp-irinotecan liposomes evidently increased the uptake of irinotecan and showed significant antitumor efficacy in the xenografted A549 cancer cells in nude mice by intravenous administration. The mechanisms were defined to be two aspects: GE11 exhibits high affinity for EGFR binding and the degradation of the HA by HAase results in the long-chain PEG removal and exposure of the previously hidden surface-attached TATp to enhance the target cell internalization.

Conclusion: Our findings suggest that this functional liposomal platform may provide a novel strategy for treating lung cancers because of effective intracellular delivery.

NanoTRAIL-Oncology: A Strategic Approach in Cancer Research and Therapy

TRAIL is a member of the tumor necrosis factor superfamily that can largely trigger apoptosis in a wide variety of cancer cells, but not in normal cells. However, insufficient exposure to cancer tissues or cells and drug resistance has severely impeded the clinical application of TRAIL. Recently, nanobiotechnology has brought about a revolution in advanced drug delivery for enhanced anticancer therapy using TRAIL. With the help of materials science, immunology, genetic engineering, and protein engineering, substantial progress is made by expressing fusion proteins with TRAIL, engineering TRAIL on biological membranes, and loading TRAIL into functional nanocarriers or conjugating it onto their surfaces. Thus, the nanoparticle-based TRAIL (nanoTRAIL) opens up intriguing opportunities for efficient and safe bioapplications. In this review, the mechanisms of action and biological function of TRAIL, as well as the current status of TRAIL treatment, are comprehensively discussed. The application of functional nanotechnology combined with TRAIL in cancer therapy is also discussed.

Photo-excitable hybrid nanocomposites for image-guided photo/TRAIL synergistic cancer therapy

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can induce apoptosis in cancer cells without toxicity to normal cells. However, the efficiency is greatly limited by its short half-life and wild resistance in various cancer cells. In this study, we reported a micellar hybrid nanoparticle to carry TRAIL ligand (denoted as IPN@TRAIL) for a novel photo-excited TRAIL therapy. These IPN@TRAIL offered increased TRAIL stability, prolonged half-life and enhanced tumor accumulation, monitored by dual mode imaging. Furthermore, IPN@TRAIL nanocomposites enhanced wrapped TRAIL therapeutic efficiency greatly towards resistant cancer cells by TRAIL nanovectorization. More importantly, when upon external laser, these nanocomposites not only triggered tumor photothermal therapy (PTT), but also upregulated the expression of death receptors (DR4 and DR5), resulting in a greater apoptosis mediated by co-delivered TRAIL ligand. Such photo/TRAIL synergistic effect showed its great killing effects in a controllable manner on TRAIL-resistant A549 tumor model bearing mice. Finally, these nanocomposites exhibited rapid clearance without obvious systemic toxicity. All these features rendered our nanocomposites a promising theranostic platform in cancer therapy.

2D Ultrathin MXene-Based Drug-Delivery Nanoplatform for Synergistic Photothermal Ablation and Chemotherapy of Cancer

Two-dimensional (2D) MXenes, as a new 2D functional material nanosystem, have been extensively explored for broad applications. However, their specific performance and applications in theranostic nanomedicine have still rarely been explored. This work reports on the drug-delivery performance and synergistic therapeutic efficiency of Ti₃ C₂ MXenes for highly efficient tumor eradication. These Ti₃ C₂ MXenes not only possess high drug-loading capability of as high as 211.8%, but also exhibit both pH-responsive and near infrared laser-triggered on-demand drug release. Especially, based on the high photothermal-conversion capability of Ti₃ C₂ MXenes, they have been further explored for efficient tumor eradication by synergistic photothermal ablation and chemotherapy, which has been systematically demonstrated both in vitro and in vivo. These Ti₃ C₂ MXenes have also been demonstrated as the desirable contrast agents for photoacoustic imaging, showing the potential for diagnostic-imaging guidance and monitoring during therapy. The high in vivo histocompatibility of Ti₃ C₂ and their easy excretion out of the body have been evaluated and demonstrated, showing the potential high biosafety for further clinical translation. This work paves a new way for broadening biomedical applications of MXenes in nanomedicine where they can exert the high performance and functionality for synergistic therapy, especially on combating cancer.

pH Responsive Doxorubicin Delivery by Fluorous Polymers for Cancer Treatment

Polymeric nanoparticles have emerged as valuable drug delivery vehicles as they improve solubility of hydrophobic drugs, enhance circulation lifetime, and can improve the biodistribution profile of small-molecule therapeutics. These nanoparticles can take on a host of polymer architectures including polymersomes, hyperbranched nanoparticles, and dendrimers. We have recently reported that simple low molecular weight fluorous copolymers can self-assemble into nanoparticles and show exceptional passive targeting into multiple tumor models. Given the favorable biodistribution of these particles, we sought to develop systems that enable selective delivery in acidic environments, such as the tumor microenvironment or the lysosomal compartment. In this report, we describe the synthesis and in vitro biological studies of a pH-responsive doxorubicin (DOX) fluorous polymer conjugate. A propargyl DOX hydrazone was synthesized and covalently attached to a water-dispersible fluorous polymer composed of trifluoroethyl methacrylate (TFEMA) and oligo(ethylene glycol) methyl ether methacrylate (OEGMEMA) using the ligand-accelerated copper-catalyzed azide-alkyne cycloaddition. Driven by the high fluorine content of the copolymer carrier, the DOX-copolymer formed stable micelles under aqueous conditions with a hydrodynamic diameter of 250 nm. The DOX-copolymer showed internalization into multiple in vitro models for breast and ovarian cancer. Cytotoxicity assays demonstrated efficacy in both breast and ovarian cancer with overall efficacy being highly dependent on the cell line chosen. Taken together, these results present a platform for the pH-triggered delivery of DOX from a fluorous micelle carrier effective against multiple cancer models in vitro.

Metalla-aromatic loaded magnetic nanoparticles for MRI/photoacoustic imaging-guided cancer phototherapy

In this study, metalla-aromatic agents and a cluster of superparamagnetic iron oxide nanoparticles were loaded inside a micellar carrier and used for MRI/PA imaging-guided PTT/PDT synergistic cancer therapy.

Eumelanin–Fe3O4 hybrid nanoparticles for enhanced MR/PA imaging-assisted local photothermolysis

In this work, we report on biodegradable eumelanin–Fe₃O₄ hybrid nanoparticles (euMel–Fe₃O₄ NPs) for multiple imaging-assisted local photothermolysis.

MDR in cancer: Addressing the underlying cellular alterations with the use of nanocarriers

Multidrug resistance (MDR) is associated with a wide range of pathological changes at different cellular and intracellular levels. Nanoparticles (NPs) have been extensively exploited as the carriers of MDR reversing payloads to resistant tumor cells. However, when properly formulated in terms of chemical composition and physicochemical properties, NPs can serve as beyond delivery systems and help overcome MDR even without carrying a load of chemosensitizers or MDR reversing molecular cargos. Whether serving as drug carriers or beyond, a wise design of the nanoparticulate systems to overcome the cellular and intracellular alterations underlying the resistance is imperative. Within the current review, we will initially discuss the cellular changes occurring in resistant cells and how such changes lead to chemotherapy failure and cancer cell survival. We will then focus on different mechanisms through which nanosystems with appropriate chemical composition and physicochemical properties can serve as MDR reversing units at different cellular and intracellular levels according to the changes that underlie the resistance. Finally, we will conclude by discussing logical grounds for a wise and rational design of MDR reversing nanoparticulate systems to improve the cancer therapeutic approaches.

Nucleolin-targeted selenium nanocomposites with enhanced theranostic efficacy to antagonize glioblastoma

Glioblastoma is considered as the most lethal cancer, due to the inability of chemotherapeutic agents to reach the glioma core as well as the infiltration zone of the invasive glioma cells. Nanotechnology based delivery systems bring new hope to cancer targeted therapy and diagnosis owing to their enhancement of selective cellular uptake and cytotoxicity to cancer cells through various smart designs. We prepared a novel selenium-based composite nanosystem (QDs/Se@Ru(A)) surface functionalized with the AS1411 aptamer and loaded with quantum dots to realize selectivity against glioblastoma and enhance theranostic effects. This cancer targeted nanosystem significantly enhanced the cellular uptake in glioma cells through nucleolin mediated endocytosis, and increased selectivity between cancer and normal cells. The QDs/Se@Ru(A) nanosystem can also be used for spontaneous fluorescence of biological probes to explore their localization in cancer cells, because of the green fluorescent quantum dots loaded into the selenium nanoparticles. QDs/Se@Ru(A) promotes excess reactive oxygen species (ROS) production in glioma cells to induce DNA damage, thus activating diverse downstream signaling pathways, and inhibiting proliferation of U87 cells through the G2/M phase cycle. Thus, this study provides an effective strategy to design a theranostic agent to simultaneously realize cell imaging and therapy for glioblastoma treatment.

Self-Assembled Bifunctional Peptide as Effective Drug Delivery Vector with Powerful Antitumor Activity

E-cadherin/catenin complex is crucial for cancer cell migration and invasion. The histidine-alanine-valine (HAV) sequence has been shown to inhibit a variety of cadherin-based functions. In this study, by fusing HAV and the classical tumor-targeting Arg-Gly-Asp (RGD) motif and Asn-Gly-Arg (NGR) motif to the apoptosis-inducing peptide sequence-AVPIAQK, a bifunctional peptide has been constructed with enhanced tumor targeting and apoptosis effects. This peptide is further processed as a nanoscale vector to encapsulate the hydrophobic drug docetaxel (DOC). Bioimaging analysis shows that peptide nanoparticles can penetrate into xenograft tumor cells with a significantly long retention in tumors and high tumor targeting specificity. In vivo, DOC/peptide NPs are substantially more effective at inhibiting tumor growth and prolonging survival compared with DOC control. Together, the findings of this study suggest that DOC/peptide NPs may have promising applications in pulmonary carcinoma therapy.

Multifunctional gold-nanoparticles: A nanovectorization tool for the targeted delivery of novel chemotherapeutic agents

Due to their small size and unique properties, multifunctional nanoparticles arise as versatile delivery systems easily grafted with a vast array of functional moieties, such as anticancer cytotoxic chemotherapeutics and targeting agents. Here, we formulated a multifunctional gold-nanoparticle (AuNP) system composed of a monoclonal antibody against epidermal growth factor receptor (EGFR) (anti-EGFR D-11) for active targeting and a Co(II) coordination compound [CoCl(H₂O)(phendione)₂][BF₄] (phendione=1,10-phenanthroline-5,6-dione) (TS265) with proven antiproliferative activity towards cancer cells (designated as TargetNanoTS265). The efficacy of this nanoformulation, and the non-targeted counterpart (NanoTS265), were evaluated in vitro using cancer cell models and in vivo using mice xenografts. Compared to the free compound, both nanoformulations (TargetNanoTS265 and NanoTS265) efficiently delivered the cytotoxic cargo in a controlled selective manner due to the active targeting, boosting tumor cytotoxicity. Treatment of HCT116-derived xenografts tumors with TargetNanoTS265 led to 93% tumor reduction. This simple conceptual nanoformulation demonstrates the potential of nanovectorization of chemotherapeutics via simple assembly onto AuNPs of BSA/HAS-drug conjugates that may easily be expanded to suit other cargo of novel compounds that require optimized controlled delivery to cancer target.

Inorganic Nanocarriers Overcoming Multidrug Resistance for Cancer Theranostics

Cancer multidrug resistance (MDR) could lead to therapeutic failure of chemotherapy and radiotherapy, and has become one of the main obstacles to successful cancer treatment. Some advanced drug delivery platforms, such as inorganic nanocarriers, demonstrate a high potential for cancer theranostic to overcome the cancer-specific limitation of conventional low-molecular-weight anticancer agents and imaging probes. Specifically, it could achieve synergetic therapeutic effects, demonstrating stronger killing effects to MDR cancer cells by combining the inorganic nanocarriers with other treatment manners, such as RNA interference and thermal therapy. Moreover, the inorganic nanocarriers could provide imaging functions to help monitor treatment responses, e.g., drug resistance and therapeutic effects, as well as analyze the mechanism of MDR by molecular imaging modalities. In this review, the mechanisms involved in cancer MDR and recent advances of applying inorganic nanocarriers for MDR cancer imaging and therapy are summarized. The inorganic nanocarriers may circumvent cancer MDR for effective therapy and provide a way to track the therapeutic processes for real-time molecular imaging, demonstrating high performance in studying the interaction of nanocarriers and MDR cancer cells/tissues in laboratory study and further shedding light on elaborate design of nanocarriers that could overcome MDR for clinical translation.