Self-assembled micellar nanocomplexes comprising green tea catechin derivatives and protein drugs for cancer therapy

Anti-neoplastic Potential of Flavonoids and Polysaccharide Phytochemicals in Glioblastoma

Clinically, gliomas are classified into four grades, with grade IV glioblastoma multiforme being the most malignant and deadly, which accounts for 50% of all gliomas. Characteristically, glioblastoma involves the aggressive proliferation of cells and invasion of normal brain tissue, outcomes as poor patient prognosis. With the current standard therapy of glioblastoma; surgical resection and radiotherapy followed by adjuvant chemotherapy with temozolomide, it remains fatal, because of the development of drug resistance, tumor recurrence, and metastasis. Therefore, the need for the effective therapeutic option for glioblastoma remains elusive. Previous studies have demonstrated the chemopreventive role of naturally occurring pharmacological agents through preventing or reversing the initiation phase of carcinogenesis or arresting the cancer progression phase. In this review, we discuss the role of natural phytochemicals in the amelioration of glioblastoma, with the aim to improve therapeutic outcomes, and minimize the adverse side effects to improve patient's prognosis and enhancing their quality of life.

Recent development of amorphous metal coordination polymers for cancer therapy

Nanoscale metal coordination polymers (NCPs), built from metal ions and organic ligands, have attracted tremendous interest in biomedical applications. This is mainly due to their mesoporous structure, tunable size and morphology and versatile functionality. NCPs can be further divided into nanoscale metal-organic frameworks (NMOFs) and amorphous coordination polymer particles (ACPPs) depending on their structural crystallinity. NMOFs as nanocarriers have been extensively reviewed. However, the highlights of ACPPs as theranostic nanoplatforms are still limited. In this review, the recent progress of ACPPs as theranostic nanoplatforms is summarized based on what types of organic linkers used. The ACPPs are divided into three main parts: photosensitizers-based ACPPs, chemical drugs-based ACPPs, and biomolecules-based ACPPs. Finally, the prospects and challenges of the ACPPs for enhanced biomedical applications are also discussed. STATEMENT OF SIGNIFICANCE: Over the last decades, amorphous metal coordination polymers (ACPPs), constructed by metal ions and organic linkers, have attracted enormous interest in cancer treatment owing to their high drug loading capability, facile synthetic procedures, low long-term toxicity, and mild preparation conditions. In this review, we highlight the recent progress of ACPPs for biomedical application based on different types of organic building blocks including photosensitizers, chemical drugs, and biomolecules. Moreover, the prospects and challenges of ACPPs for clinical application are also discussed. We hope this review entitled "Recent development of amorphous metal coordination polymers for cancer therapy" would arise the researchers' interest in this field to accelerate their clinical application in cancer therapy.

Nanomedicine-Cum-Carrier by Co-Assembly of Natural Small Products for Synergistic Enhanced Antitumor with Tissues Protective Actions

The application of natural small products with self-assembly characteristics in a drug-delivery system is attractive for biomedical applications because of its inherent biological safety and pharmacological activity, and there is no complex structural modification process. However, drug carriers with pharmacological effects have not been developed enough. Here, we report a pure natural nanomedicine-cum-carrier (NMC) drug delivery system. The NMC is formed by the direct co-assembly of two small molecular natural compounds through noncovalent interaction, and a molecular dynamics model for predicting the co-assembly of two small molecular compounds was established. The representative co-assembled NMC (oleanolic acid and glycyrrhetinic acid) not only shows excellent stability, high drug loading, and sustained release characteristics but also the co-assembled NMC formed by two small molecular compounds has a synergistic antitumor effect (CI < 0.7). After drug loading, the antitumor effect is further improved. In addition, this NMC highlights the unique advantages of active natural products in biosafety and health benefits. Compared with free drugs, it can reduce the liver damage caused by chemotherapy drugs through upregulating key antioxidant pathways. Compared to nonpharmacologically active drug delivery systems, it can reduce the risk of nanotoxicity. Taken together, this co-assembly drug-carrier system overcomes the shortcomings that pharmacologically active compounds cannot be directly applied, enhances the pharmacological activity of bioactive drug carriers, improves the antitumor efficacy, and slows down the side effects induced by chemotherapy drugs and the additional toxicity caused by long-term use of non-bioactive nanocarriers.

Nanotheranostics With the Combination of Improved Targeting, Therapeutic Effects, and Molecular Imaging

There is an increasing interest in the design of targeted carrier systems with combined therapeutic and diagnostic modalities. Therapeutic modalities targeting tumors with single ligand-based targeting nanocarriers are insufficient for proficient delivery and for targeting two different surface receptors that are overexpressed in cancer cells. Here, we evaluated an activated nanoparticle delivery system comprising fucoidan/hyaluronic acid to improve therapeutic efficacy. The system comprised polyethylene glycol-gelatin-encapsulated epigallocatechin gallate (EGCG), poly (D,L-lactide-co-glycolide; PLGA), and stable iron oxide nanoparticles (IOs). The latter enables targeting of prostate cancers in their molecular images. We demonstrate the transfer of nanoparticles and their entry into prostate cancer cells through ligand-specific recognition. This system may prove the benefits of drug delivery that enhances the inhibition of cell growth through apoptosis induction. Moreover, the improved targeting of nanotheranostics significantly suppressed orthotopic prostate tumor growth and more accurately targeted tumors compared with systemic combination therapy. In the presence of nanoparticles with iron oxides, the hypointensity of the prostate tumor was visualized on a T2-weignted magnetic resonance image. The diagnostic ability of this system was demonstrated by accumulating fluorescent nanoparticles in the prostate tumor from the in vivo imaging system, computed tomography. It is suggested that theranostic nanoparticles combined with a molecular imaging system can be a promising cancer therapy in the future.

Dexamethasone-loaded H2O2-activatable anti-inflammatory nanoparticles for on-demand therapy of inflammatory respiratory diseases

Asthma is a common airway inflammatory disorder, characterized by increased infiltration of leukocytes and bronchoconstriction. Dexamethasone (DEX) has been widely used in the treatment of allergic asthma. However, long-term and frequent use of DEX has side effects. We therefore reasoned that if drug carriers have intrinsic anti-inflammatory and anti-asthmatic activity and synergize with drug payloads, a low dose of DEX could exert sufficient therapeutic effects. In this study, we developed DEX-loaded H₂O₂-activatable boronate maltodextrin (DEX-BM) nanoparticles. DEX-BM nanoparticles released DEX in a H₂O₂-triggered manner and remarkably suppressed the expression of pro-inflammatory cytokines in activated macrophages and lung epithelial cells. In the studies of a murine allergic asthma model, DEX-BM nanoparticles (5 mg/kg) effectively inhibited the inflammatory cell infiltration and airway inflammation than equivalent DEX and BM nanoparticles without noticeable side effects. We anticipate that DEX-BM nanoparticles hold great potential as therapeutic agents for various airway inflammatory diseases.

Enzyme-mediated one-pot synthesis of hydrogel with the polyphenol cross-linker for skin regeneration

Polyphenols can trigger immunity that activates intracellular anti-inflammatory signaling and prevents external infections. In this study, we report the fabrication of chitosan-based hydrogels with epigallocatechin gallate (EGCG) using enzyme-mediated one-pot synthesis. The tyrosinase-mediated oxidative reaction of the phenolic rings of EGCG with the primary amines on chitosan results in stable EGCG-chitosan hydrogels. The EGCG concentrations contributed to the cross-linking density and physical properties of EGCG-chitosan hydrogels. Furthermore, EGCG-chitosan hydrogels maintained intrinsic properties such as antibacterial and antioxidant effects. When endotoxin-activated RAW 264.7 macrophage cells were cultured with EGCG-chitosan hydrogels, the hydrogels reduced the inflammatory response of the RAW 264.7 cells. Furthermore, subcutaneous implantation of EGCG-chitosan hydrogels reduced endogenous macrophage and monocyte activation. When the EGCG-chitosan hydrogels were applied to a full-skin defect wound, they facilitated skin regeneration. Our study demonstrates that the one-pot synthesized EGCG-chitosan hydrogels can be applied in broad tissue regeneration applications that require immune modulation.

Prospects of nanodentistry for the diagnosis and treatment of maxillofacial pathologies and cancers

Despite the commendable milestones achieved in molecular maxillofacial pathology in the last decade, there remains a paucity of utilization of ancillary nanomolecular tools that complement the omics-based approaches. As the advent of omics science transforms our understanding of tumour biology from a phenomenological to a complex network (systems-oriented) paradigm, several ancillary tools have emerged to improve the scope of individualized medicine. Targeted nano drug delivery systems have significantly reduced toxicity of chemotherapeutic agents in a precise manner. Many conventional cancer therapies are limited in efficacy and this has led to the emergence of nanomedical innovations. Despite the success of nanomedicine, a major challenge that persists is tumour heterogeneity and biological complexity. A good understanding of the interaction between inorganic nanoparticles and the biological systems has led to the development of better tools for individualized medicine. Tools such as the composite organic-inorganic nanoparticles (COINs) and the quantum dots (QD) have significantly improved the identification and quantification of disease biomarkers, histopathological detection methods, as well as improving the clinical translation and utility of these nanomaterials. Nanomedicine has lent credence to several multipronged theranostic applications in medicine, and this has improved the medical practice tremendously. Despite the palpable influence of nanomedicine on the delivery of individualized medical therapies, the term "nanodentistry" remains in the background without much hype, albeit some progress has been made in this area. Hence, this review discusses the potential and challenges of nanodentistry in the diagnosis and treatment of maxillofacial pathologies, particularly cancer in resource-limited settings.

Prevention of Obesity Related Diseases through Laminarin-induced targeted delivery of Bindarit

Rationale: The developement of oral targeted therapeutics for obesity and obesity-related diseases is challenging, as these diseases involve multiple lesions distributed throughout the whole body. Herein, we report a successful stragety for targeted oral delivery of bindarit to multiple obesity-related lesions including inflamed adipose tissue, fatty liver and atherosclerotic plaques.

Methods: The computer simulation from atomstic to mesoscale was first applied for designing bindarit-loaded nanoparticles (pBIN) and laminarin-modified bindarit-loaded nanoparticles (LApBIN). Then pBIN were suceesfully prepared using a dialysis procedure, and LApBIN were prepared though the interaction bewtween laminarin and pBIN. The physiochemical properties, in vitro and in vivo pharmacokinetics, oral targeting capability and in vivo efficacy of LApBIN in various obesity-related diseases were examined.

Results: LApBIN were sucessfully designed and prepared. Following oral administration of LApBIN, the nanoparticles could be sucessully orally adsorbed and translocated to monocytes. Contributed by the recruitment of monocytes to multiple obesity-related lesions, LApBIN successfully delivered bindarit to these lesions, and effectively suppressed inflammation there, which exerted successful preventive effects on high-fat-diet-induced obesity, insulin resistance, fatty liver and atherosclerosis.

Conclusions:This strategy could represent a promising approach to develop effective oral treatments for obesity and other metabolic diseases.

Oral delivery of anti-TNF antibody shielded by natural polyphenol-mediated supramolecular assembly for inflammatory bowel disease therapy

Rationale: Anti-tumor necrosis factor (TNF) therapy is a very effective way to treat inflammatory bowel disease. However, systemic exposure to anti-TNF-α antibodies through current clinical systemic administration can cause serious adverse effects in many patients. Here, we report a facile prepared self-assembled supramolecular nanoparticle based on natural polyphenol tannic acid and poly(ethylene glycol) containing polymer for oral antibody delivery. Method: This supramolecular nanoparticle was fabricated within minutes in aqueous solution and easily scaled up to gram level due to their pH-dependent reversible assembly. DSS-induced colitis model was prepared to evaluate the ability of inflammatory colon targeting ability and therapeutic efficacy of this antibody-loaded nanoparticles. Results: This polyphenol-based nanoparticle can be aqueous assembly without organic solvent and thus scaled up easily. The oral administration of antibody loaded nanoparticle achieved high accumulation in the inflamed colon and low systemic exposure. The novel formulation of anti-TNF-α antibodies administrated orally achieved high efficacy in the treatment of colitis mice compared with free antibodies administered orally. The average weight, colon length, and inflammatory factors in colon and serum of colitis mice after the treatment of novel formulation of anti-TNF-α antibodies even reached the similar level to healthy controls. Conclusion: This polyphenol-based supramolecular nanoparticle is a promising platform for oral delivery of antibodies for the treatment of inflammatory bowel diseases, which may have promising clinical translation prospects.

General Nanomedicine Platform by Solvent-Mediated Disassembly/Reassembly of Scalable Natural Polyphenol Colloidal Spheres

The current strategy using the assembly of medicines and active functional molecules to develop nanomedicines often requires both molecules to have a specific matched chemical molecular structure; however, this is often difficult to predict, execute, and control in practical applications. Herein, we reported a general solvent-mediated disassembly/reassembly strategy for preparing nanomedicines based on epigallocatechin gallate (EGCG) active molecules. The polyphenol colloidal spheres (CSs) were self-assembled from molecular condensed EGCG in aqueous solution but disassembled in organic solvents and reassembled in aqueous solution. The solvent-mediated disassembly and reassembly capability of CSs gave rise to the active binding of condensed EGCG to various hydrophilic and hydrophobic guest molecules. The maximum encapsulation and drug-loading rate of reassembled CSs/DOX were 90 and 44%, respectively, and the nanomedicines could reverse drug resistance of tumor cells and exhibit enhanced therapeutic effects for breast cancer. Last but not least, 37.3 g of polyphenol CSs was massively produced at one time with a yield of 74.6%, laying a solid foundation for the practical applications of reassembled nanomedicines. The present strategy leading to a general nanomedicines platform was concise and highly efficient for both hydrophilic and hydrophobic drugs, making a breakthrough for low loading dilemma of current nanomedicines, and would open up a new direction for the preparation of nanocarriers, nanocomposites, and nanomedicines from natural polyphenols.

Augmenting Therapeutic Potential of Polyphenols by Hydrogen-Bonding Complexation for the Treatment of Acute Lung Inflammation

Dysregulated inflammation is considered as an essential pathological process in inflammation-associated diseases, which would be aggravated by high levels of reactive oxygen species (ROS) generation inducing oxidative stress. Currently, extensive attention has been paid to polyphenolic compounds owing to their broad spectrum biological activities, such as antioxidant and anti-inflammatory effects, while their therapeutic potential has been compromised by the poor stability, short plasma half-life, and low bioavailability. Given that polyphenols have a wide range of structural characteristics and various physicochemical properties, there remains a real challenge toward green, mass production of universal nanocarriers for effective entrapment of these active pharmaceutical ingredients. In this study, we adopted a flash nanocomplexation (FNC) platform to prepare nanocomplexes comprising polyphenols and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) enabled by hydrogen bonding. We confirmed that the molecular structure of polyphenols has a great influence on their complexation with TPGS, and stable nanocomplexes were formed when the number of phenolic hydroxyl groups of polyphenols was above the value of 8. These hydrogen-bonded nanocomplexes produced by an FNC apparatus exhibited well-controlled quality with uniform size, good colloidal stability, and high batch-to-batch repeatability, thus improving the druggability as potent nanotherapeutics for antioxidant and anti-inflammatory applications. In vivo experiments indicated that the optimal nanocomplex (EGCG-NC) can be applied to ameliorate acute lung injury in a mice model after nasal administration. These results proved that polyphenols formulated with TPGS for nanocomplex formation through hydrogen-bonding complexation could augment their therapeutic potential for modulating hyperactive inflammation in the treatment of acute lung inflammation.

Preparation of Strong Antioxidative, Therapeutic Nanoparticles Based on Amino Acid-Induced Ultrafast Assembly of Tea Polyphenols

Nanoformulations offer the opportunity to overcome the shortcomings of drug molecules, such as low solubility, side effects, insufficient stability, etc., but in most of the current nanomedicines, nanocarriers as excipients do not directly participate in the therapy procedure. Accordingly, it is promising to develop the nanotherapeutics composed entirely of pharmaceutically active molecules. Tea polyphenols, especially epigallocatechin gallate (EGCG), are a kind of natural antioxidants with various biological and health beneficial effects and are extensively investigated as nutrients and anticancer drugs. Here, the size-tunable and highly active polyphenol nanoparticles were conveniently synthesized in water and could be massively produced with a simple facility. Compared to the previous strategies, either molecular assembly via oxidative coupling or combination with other biomacromolecules, the present preparation was conducted by the amino acid-triggered Mannish condensation reactions, thus permitting the flexible molecular design of various polyphenol nanoparticles by selecting different amino acids. This straightforward and ultrafast method actually opens up a novel means to make use of naturally reproducible polyphenols. Moreover, inheriting the salient properties of EGCG, these nanoparticles show strong antioxidation capacity, 10-fold higher than the extensively investigated polydopamine nanoparticles, and they are biosafe but have therapeutic effects, according to the in vitro and in vivo assessments of anticancer activity, which is promising for various biomedical purposes.

Polyphenol-Mediated Assembly for Particle Engineering

Polyphenols are naturally occurring compounds that are ubiquitous in plants and display a spectrum of physical, chemical, and biological properties. For example, they are antioxidants, have therapeutic properties, absorb UV radiation, and complex with metal ions. Additionally, polyphenols display high adherence, which has been exploited for assembling nanostructured materials. We previously reviewed the assembly of different phenolic materials and their applications (Angew. Chem. Int. Ed. 2019, 58, 1904-1927); however, there is a need for a summary of the fundamental interactions that govern the assembly, stability, and function of polyphenol-based materials. A detailed understanding of interactions between polyphenols and various other building blocks will facilitate the rational design and assembly of advanced polyphenol particles for specific applications. This Account discusses how different interactions and bonding (i.e., hydrogen, π, hydrophobic, metal coordination, covalent, and electrostatic) can be leveraged to assemble and stabilize polyphenol-based particles for diverse applications. In polyphenol-mediated assembly strategies, the polyphenols typically exert more than one type of stabilizing attractive force. However, one interaction often dominates the assembly process and dictates the physicochemical behavior of the particles, which in turn influences potential applications. This Account is thus divided into sections that each focus on a key interaction with relevant examples of applications to highlight structure-function relationships. For example, metal coordination generally becomes weaker at lower pH, which makes it possible to engineer metal-phenolic materials with a pH-responsive disassembly profile suitable for drug delivery. Engineered particles, such as hollow capsules, mesoporous and core-shell particles, and self-assembled nanoparticles are some of the systems that are covered to highlight how polyphenols interact with other building blocks and therefore make up the major focus of this Account. Some of the applications of these materials exemplified in this Account include drug delivery, catalysis, environmental remediation, and forensics. Finally, a perspective is provided on the current challenges and trends in polyphenol-mediated particle assembly, and viable near-term strategies for further elucidating the interplay of various competing interactions in particle formation are discussed. This Account is also expected to serve as a reference to guide fundamental research and facilitate the rational design of polyphenol-based materials for diverse emerging applications.

Nanoparticles Derived from the Natural Antioxidant Rosmarinic Acid Ameliorate Acute Inflammatory Bowel Disease

Rosmarinic acid (RA), one of the most important polyphenol-based antioxidants, has received growing interest because of its bioactive properties, including anti-inflammatory, anticancer, and antibacterial activities. Despite the high therapeutic potential of RA, its intrinsic properties of poor water solubility and low bioavailability have limited its translation into the clinic. Here, we report on the synthesis and preparation of PEGylated RA-derived nanoparticles (RANPs) and their use as a therapeutic nanomedicine for treatment of inflammatory bowel disease (IBD) in a dextran sulfate sodium (DSS)-induced acute colitis mouse model. PEGylated RA, synthesized via a one-step process from RA and a PEG-containing amine, self-assembled in buffer to form nanoparticles (RANPs) with a diameter of 63.5 ± 4.0 nm. The resulting RANPs showed high colloidal stability in physiological medium up to 2 weeks. RANPs were capable of efficiently scavenging H2O2, thereby protecting cells from H2O2-induced damage. Furthermore, the corticosteroid drug, dexamethasone (DEX), could be loaded into RANPs and released in response to a reactive oxygen species stimulus. Intravenously administered RANPs exhibited significantly improved pharmacokinetic parameters compared with those of the parent RA and were preferentially localized to the inflamed colon. Intravenous administration of RANPs in DSS-induced colitis mice substantially mitigated colonic inflammation in a dose-dependent manner compared with the parent RA, as evidenced by significantly reduced disease activity index scores, body weight loss, and colonic inflammatory damage. In addition, RANPs suppressed expression and production of typical pro-inflammatory cytokines in the inflamed colon. Furthermore, DEX-loaded RANPs showed enhanced therapeutic efficacy in the colitis model compared with bare RANPs at the equivalent dose, indicating synergy with a conventional medication. These findings suggest that RANPs deserve further consideration as a potential therapeutic nanomedicine for the treatment of various inflammatory diseases, including IBD.

Synergistic Release of Crop Nutrients and Stimulants from Hydroxyapatite Nanoparticles Functionalized with Humic Substances: Toward a Multifunctional Nanofertilizer

The use of salt- or macro-sized NPK fertilizers is typically associated with low nutrient use efficiency and water eutrophication. Nanotechnology can overcome such drawbacks, but its practical application on a large scale is limited by (i) high costs and difficult scale-up of nanoparticle synthesis, (ii) questionable advantages over traditional methods, and (iii) health hazards related to nanomaterial introduction in the food stream and the environment. Here, we report on a novel biocompatible and multifunctional P nanofertilizer obtained by self-assembling natural or synthetic humic substances and hydroxyapatite nanoparticles using a simple and straightforward dipping process, exploiting the interaction between the polyphenolic groups of humic substances and the surface of nanohydroxyapatite. Pot tests using the as-prepared materials were performed on Zea mays as a model crop, and the results were compared to those obtained using commercial fused superphosphate and bare nanohydroxyapatites. A significant improvement, in terms of early plant growth, corn productivity, rhizosphere bacteria, and the resistance to NaCl-induced abiotic stresses, was achieved using hydroxyapatite nanoparticles assembled with humic substances. These effects were ascribed to the synergistic co-release of phosphate ions and humic substances, which are two types of plant-beneficial agents for crop nutrition and stimulation, respectively. The release patterns were proven to be tunable with the amount of humic substances adsorbed on the nanoparticles, inducing competition between humic-substance-driven phosphorous dissolution and block of water contact. Such positive effects on plant growth in association with its intrinsic biocompatibility, simple synthesis, and multifunctionality qualify this novel nanofertilizer as a promising material for large-scale use in the agronomic field.

Transforming Complexity to Simplicity: Protein-Like Nanotransformer for Improving Tumor Drug Delivery Programmatically

It was difficult for nanodrugs to simultaneously meet the contradictory requirements of prolonged circulation time, augmented cellular uptake, rapid lysosome escape, precise drug release, and tumor penetration in tumor drug delivery. We prepared a nanotransformer (DTIG) through assembling doxorubicin, tannic acid, and indocyanine green to overcome this dilemma. Hydrophilic DTIG showed prolonged blood circulation time. Besides, DTIG could be efficiently internalized by tumor cells through transforming into hydrophobic particles in an acidic tumor microenvironment. Subsequently, oversized hydrophobic particles were further formed in acidic lysosomes to escape from it through rupturing the lysosome. These hydrophobic DTIGs could rapidly revert to a smaller hydrophilic nanoassembly and release the payloads in cytoplasm. Similar to denaturation and renaturation of protein, these high-efficiency instantaneous transformations were activated by proton. Besides, photothermal therapy of DTIG promoted drug penetration efficiency in tumor. This optimized drug delivery process of DTIG finally offered potent antitumor efficacy and an obvious advantage on prognosis.

Preparation of a novel emulsifier by self-assembling of proanthocyanidins from Chinese bayberry (Myrica rubra Sieb. et Zucc.) leaves with gelatin

A physicochemically stable emulsion was developed by using a novel emulsifier, which was self-assembled colloidal complex of gelatin (GLT) and proanthocyanidins from Chinese bayberry (Myrica rubra Sieb et Zucc.) leaves (BLPs), with epigallocatechin-3-O-gallate (EGCG) as structure units. The GLT-BLP colloidal complexes were spherically shaped by transmission electron microscope (TEM). The data of Fourier transform infrared spectrum (FTIR), circular dichroism (CD), isothermal titration calorimetry (ITC) revealed that the main binding force between GLT and BLPs of the colloidal complexes was hydrogen bond. The incorporation of BLPs to GLT provided GLT with stronger affinity at oil-water interface and thus enhanced the physical stability of GLT-stabilizing emulsion. In addition, the emulsions stabilized by the colloidal complexes showed higher oxidation stability than that stabilized by free GLT only. The novel emulsifier developed in this study have potential applications as functional emulsifiers in food-grade emulsions with high anti-oxidation activity.

Biomimetic preparation of core-shell structured surface-enhanced Raman scattering substrate with antifouling ability, good stability, and reliable quantitative capability

The fouling and stability are two most critical limiting factors for practical applications of surface-enhanced Raman scattering (SERS)-based microfluidic electrophoresis device. Herein, we present a novel biomimetic nanoengineering strategy to achieve a SERS substrate featuring antifouling ability, good stability, and reliable quantitative capability. Typically, by employing tea polyphenol as the reducing agent, the substrate made of silver core-gold shell nanostructures in situ grown on silicon wafer surface is fabricated. The core-shell nanostructures are further embedded with internal standard molecules. Remarkably, the fabricated substrate preserves distinct SERS effects, adaptable reproducibility, and reliable quantitative ability even if the substrate is incubated with 15% H₂ O₂ , 13% HNO₃ , or 10⁸  CFU/mL bacteria, or suffered from 12-day continuous vibration at 250 rpm/min in PBS buffer. As a proof-of-concept application, the DNA-functionalized substrate is capable of precise quantification of Hg²⁺ with a limit of detection down to ca. 1 pM even in sewage water.

Tumor microenvironment-responsive prodrug nanoplatform via co-self-assembly of photothermal agent and IDO inhibitor for enhanced tumor penetration and cancer immunotherapy

Nanomedicine-based phototherapy in combination with immune checkpoint blockade therapy has been reported as a promising strategy for improved cancer immunotherapy. However, tumor penetration of nanomedicine into solid tumor is still an unresolved obstacle to an effective drug delivery, leading to limitations in their applications. Here, we developed a tumor microenvironment-responsive prodrug nanoplatform for efficient penetration and photo-immunotherapy of cancer. The prodrug nanoplatform is performed by integrating PEGylated indoleamine-2,3-dioxygenase (IDO) inhibitor (Epacadostat) and photosensitizer (Indocyanine green, ICG) into a core-shell nanostructure via intermolecular interactions, which can transform into small dual-drug complexes (<40 nm) at tumor microenvironment. The resulting small dual-drug complexes could undergo caveolae-mediated endocytosis, enhance cellular uptake, directly kill tumor cells, in situ trigger antitumor immune response and modulate IDO-mediated immunosuppression. More significantly, the prodrug nanoplatform in combination with PD-L1 checkpoint blockade synergistically promoted the antitumor immunity and efficiently inhibited the growth of both primary and abscopal tumors. The present study provides a novel delivery strategy for nanoenabled phototherapy and IDO inhibition to combine PD-L1 checkpoint blockade for achieving more effective therapy of solid tumors.

Tumor microenvironment-activated self-recognizing nanodrug through directly tailored assembly of small-molecules for targeted synergistic chemotherapy

Carrier-free nanodrug via small-molecule assembly is a promising alternative strategy for tumor therapy. Thus, developing a self-recognizing carrier-free nanodrug without introduction of foreign ligand is very attractive to meet both targeting and therapeutic requirements while reducing structural complexity. Here we fabricated a tumor microenvironment-activated self-targeting nanodrug, via co-assembly of hydroxycamptothecin (HCPT) and bi-functional methotrexate (MTX, not only has antitumor effect but also shows innate affinity towards folate receptors) followed by surface covering through acidity-responsive polyethylene glycol (PEG). Notably, the morphology and size of MTX-HCPT nanodrug could be tuned by varying the drug-to-drug ratio and assembly time. The PEG shell of our nanodrug could be detached in response to acidic tumor microenvironment, and then MTX could be exposed for self-targeting to enhance tumor cell uptake. Subsequently, the shell-detached nanodrug could be dissociated in relatively stronger acidic lysosomal environment, resulting in burst release of both drugs. Further in vitro and in vivo studies demonstrated that our nanodrug showed a ~2.98-fold increase in cancer cell uptake, a ~1.25-fold increase in drug accumulation at tumor site, a significantly lower CI₅₀ value of ~0.3, a ~27.3% improvement in tumor inhibition comparing with the corresponding non-responsive nanodrug. Taken together, the here reported tumor microenvironment-activated self-recognizing nanodrug might be an extremely promising strategy for synergistically enhancing chemotherapy efficiency with minimized side effects.

Exploration of the Natural Active Small-Molecule Drug-Loading Process and Highly Efficient Synergistic Antitumor Efficacy

The development and application of nano-drug carriers might provide an excellent opportunity for cancer therapy. However, it is still an important challenge to realize the regulation and control of drug loading by analyzing the assembly process of carrier-loaded drugs. Herein, we show a "self-contained bioactive nanocarrier" system, which is prepared from ursolic acid, one of the very promising biologically active natural products with self-assembly properties. The study decrypts the assembly process of drug-carrier interaction and achieves the regulation of drug loading by controlling the interaction force. This nanocarrier highlights the unique advantages of active natural products in therapeutic efficacy and health benefits. In antitumor experiments, the carrier and drug demonstrated synergistic therapeutic efficacy. Furthermore, the nanocarrier is biosafe and capable of reducing the risk of liver damage induced by chemotherapeutics through the upregulation of key antioxidant pathways. Taken together, this "self-contained bioactive nanocarrier" system makes up for the drawback that conventional nanocarriers have no therapeutic efficacy and health benefits and eliminates the trouble of the toxic side effects associated with chemotherapy agents and the additional toxicity caused by long-term use of nanocarriers.

Potential of nano-phytochemicals in cervical cancer therapy

Cervical cancer is common among women with a recurrence rate of 35% despite surgery, radiation, and chemotherapy. Patients receiving chemotherapy or radiotherapy routinely experience several side effects including toxicity, non-targeted damage of tissues, hair loss, neurotoxicity, multidrug resistance (MDR), nausea, anemia and neutropenia. Phytochemicals can interfere with almost every stage of carcinogenesis to prevent cancer development. Many natural compounds are known to activate/deactivate multiple redox-sensitive transcription factors that modulate tumor signaling pathways. Polyphenols have been found to be promising agents against cervical cancer. However, applications of phytochemicals as a therapeutic drug are limited due to low oral bioavailability, poor aqueous solubility and requirement of high doses. Nano-sized phytochemicals (NPCs) are promising anti-cancer agents as they are required in minute quantities which lowers overall treatment costs. Several phytochemicals, including quercetin, lycopene, leutin, curcumin, green tea polyphenols and others have been packaged as nanoparticles and proven to be useful in nano-chemoprevention and nano-chemotherapy. Nanoparticles have high biocompatibility, biodegradability and stability in biological environment. Nano-scale drug delivery systems are excellent source for enhanced drug specificity, improved absorption rates, reduced drug degradation and systemic toxicity. The present review discusses current knowledge in the involvement of phytochemical nanoparticles in cervical cancer therapy over conventional chemotherapy.

A Metal-Polyphenol-Coordinated Nanomedicine for Synergistic Cascade Cancer Chemotherapy and Chemodynamic Therapy

The clinical application of chemotherapy is impeded by the unsatisfactory efficacy and severe side effects. Chemodynamic therapy (CDT) has emerged as an efficient strategy for cancer treatment utilizing Fenton chemistry to destroy cancer cells by converting endogenous H₂ O₂ into highly toxic reactive oxygen species. Apart from the chemotherapeutic effect, cisplatin is able to act as an artificial enzyme to produce H₂ O₂ for CDT through cascade reactions, thus remarkably improving the anti-tumor outcomes. Herein, an organic theranostic nanomedicine (PTCG NPs) is constructed with high loading capability using epigallocatechin-3-gallate (EGCG), phenolic platinum(IV) prodrug (Pt-OH), and polyphenol modified block copolymer (PEG-b-PPOH) as the building blocks. The high stability of PTCG NPs during circulation stems from their strong metal-polyphenol coordination interactions, and efficient drug release is realized after cellular internalization. The activated cisplatin elevates the intracellular H₂ O₂ level through cascade reactions. This is further utilized to produce highly toxic reactive oxygen species catalyzed by an iron-based Fenton reaction. In vitro and in vivo investigations demonstrate that the combination of chemotherapy and chemodynamic therapy achieves excellent anticancer efficacy. Meanwhile, systemic toxicity faced by platinum-based drugs is avoided through this nanoformulation. This work provides a promising strategy to develop advanced nanomedicine for cascade cancer therapy.

ATP-Charged Nanoclusters Enable Intracellular Protein Delivery and Activity Modulation for Cancer Theranostics

Protein drugs own a large share in the market and hold great prospects for the treatment of many diseases. However, the available protein drugs are limited to the extracellular target, owing to the inefficient transduction and activity modulation of proteins targeting intracellular environment. In this study, we constructed ATP-charged platforms to overcome the above-mentioned barriers for cancer theranostics. The phenylboronic acid-modified polycations (PCD) were synthesized to assemble with enzymes and shield its activity in the blood circulation. When the PCD nanoclusters reached tumor site, they effectively transported the enzymes into the cells, followed by recovering its catalytic activity after being charged with ATP. Importantly, the cascaded enzyme systems (GOx&HRPA) selectively induced starvation therapy as well as photoacoustic imaging of tumor. Our results revealed that the intelligent nanoclusters were broadly applicable for protein transduction and enzyme activity modulation, which could accelerate the clinical translation of protein drugs toward intracellular target.

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ATP-charged nanoclusters capable of enzyme activity modulation

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Universal platform for intracellular protein delivery

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Selective cellular cascaded catalysis for cancer theranostics

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Photoacoustic (PA) imaging and starvation therapy of breast cancer

Folate-grafted glycyl-glycine-melphalan conjugate self-assembled amphilphilc nanomicelles augmented drug delivery, cytotoxicity and cellular uptake in human ovarian cancer cells

Objectives: Folic acid was coupled to melphalan using glycyl-glycine (FA-Gly-Gly-Melphalan) to synthesize self-assembled nanomicelles for targeting ovarian cancer cells, SKOV3.Methods and Results: FA-Gly-Gly-Melphalan self-assembled nanomicelles were prepared with critical micellar concentration (CMC) of 12-μg/ml. The mean particle size of FA-Gly-Gly-Melphalan self-assembled nanomicelles was measured to be 95.9 ± 3.4-nm significantly (P < 0.05) higher than 73.8 ± 6.3-nm of Gly-Gly-Melphalan self-assembled nanomicelles. Subsequently, zeta-potential of FA-Gly-Gly-Melphalan self-assembled nanomicelles was estimated to be -28.0 ± 1.5-mV significantly (P < 0.05) lower than -36.6 ± 2.7-mV of Gly-Gly-Melphalan self-assembled nanomicelles. The IC₅₀ of FA-Gly-Gly-Melphalan self-assembled nanomicelles was estimated to be 4.1-μg/ml significantly (P < 0.001) lower than 14.2-μg/ml of Gly-Gly-Melphalan self-assembled nanomicelles and >18-μg/ml of melphalan. FA-Gly-Gly-Melphalan self-assembled nanomicelles preferentially accumulated in cytoplasm of SKOV3 cells nearby nucleus via receptor mediated endocytosis pathway after 24-h of incubation period, whilst Gly-Gly-Melphalan self-assembled nanomicelles were not incorporated sufficiently.Conclusion: FA-Gly-Gly-Melphalan self-assembled nanomicelles warrant in depth in vivo study for their safety, efficacy, and potency in clinical settings.

Solanesol derived therapeutic carriers for anticancer drug delivery

Metabolites of a large number of inert drug carriers can cause long-term exogenous biological toxicity. Therefore, carriers with simultaneous therapeutic effects may be a good choice for drug delivery. Herein, a series of pharmacologically active solanesol derivatives were synthesized and investigated for use as micellar drug carriers for cancer therapy. Solanesyl thiosalicylic acid (STS) was first synthesized by introducing a thiosalicylic acid group to solanesol, inspired by the characteristic structure of farnesyl thiosalicylic acid (FTS) which is a non-toxic inhibitor of all active forms of the RAS protein. Then, two amphiphilic derivatives of STS were formed with ester- and hydrazone (HZ)-bond linked methyl poly(ethylene glycol)(mPEG), mPEG-STS and mPEG-HZ-STS, respectively. The PEGylated STS could be formed stable nano-sized micelles loaded with Doxorubicin (DOX). In vitro, DOX loaded mPEG-STS and mPEG-HZ-STS micelles exhibited stronger tumor inhibition ability compared with free DOX. In vivo, blank mPEG-STS and mPEG-HZ-STS micelles showed an obvious inhibiting effect on tumor growth while the drug loaded micelles had the greatest tumor inhibition effect. The enhanced therapeutic effects and the synergistic effect observed with this solanesol-based drug delivery system could be attributed to the inherent therapeutic qualities of the drug carriers.

In vivo biocompatibility and immunogenicity of metal-phenolic gelation

In vivo forming hydrogels are of interest for diverse biomedical applications due to their ease-of-use and minimal invasiveness and therefore high translational potential. Supramolecular hydrogels that can be assembled using metal-phenolic coordination of naturally occurring polyphenols and group IV metal ions (e.g. TiIV or ZrIV) provide a versatile and robust platform for engineering such materials. However, the in situ formation and in vivo response to this new class of materials has not yet been reported. Here, we demonstrate that metal-phenolic supramolecular gelation occurs successfully in vivo and we investigate the host response to the material over 14 weeks. The TiIV-tannic acid materials form stable gels that are well-tolerated following subcutaneous injection. Histology reveals a mild foreign body reaction, and titanium biodistribution studies show low accumulation in distal tissues. Compared to poloxamer-based hydrogels (commonly used for in vivo gelation), TiIV-tannic acid materials show a substantially improved in vitro drug release profile for the corticosteroid dexamethasone (from <1 day to >10 days). These results provide essential in vivo characterization for this new class of metal-phenolic hydrogels, and highlight their potential suitability for biomedical applications in areas such as drug delivery and regenerative medicine.

Controllable silicon nanostructures featuring stable fluorescence and intrinsic in vitro and in vivo anti-cancer activity

In this manuscript, we demonstrate that the in situ growth of fluorescent silicon (Si) nanomaterials is stimulated when organosilicane molecules interact with different green teas, producing multifunctional Si nanomaterials with controllable zero- (e.g., nanoparticles), two- (e.g., nanosheets), and three- (e.g., nanospheres) dimensional nanostructures. Such green tea-originated Si nanomaterials (GTSN) exhibit strong fluorescence (quantum yield: ∼19-30%) coupled with ultrahigh photostability, as well as intrinsic anti-cancer activity with high specificity (e.g., the GTSN can accurately kill various cancer cells, rather than normal cells). Taking advantage of these unique merits, we further performed systematic in vitro and in vivo experiments to interrogate the mechanism of the green tea- and GTSN-related cancer prevention. Typically, we found that the GTSN entered the cell nuclei and induced cell apoptosis/death of cancer cells. The prepared GTSN were observed in vivo to accumulate in the tumour tissues after 14-d post-injection, leading to an efficient inhibition of tumour growth. Our results open new avenues for designing novel multifunctional and side-effect-free Si nanomaterials with controllable structures.

Targeted molecular imaging of TLR4 in hepatocellular carcinoma using zwitterionic near-infrared fluorophores

Background

Tumor-associated macrophages (TAMs) are one of the most abundant immune cell types in solid tumors and implicated in tumor progression. Toll-like receptor 4 (TLR4) is expressed in TAMs and plays a key role in immune surveillance and tumor progression. Therefore, molecular imaging of TLR4 has potential not only for detection of TAM-enriched progressing tumors, but also evaluation of TLR4 expression in tumor microenvironment.

Methods

Here, we report that near-infrared (NIR) fluorescence imaging can provide a real-time imaging of a syngeneic model of murine hepatocellular carcinoma using targeted strategy against TLR4. We conjugated a zwitterionic NIR fluorophore ZW800-1C with minimal nonspecific tissue interactions to anti-TLR4 antibody and observed its targetability. The bioconjugates showed high affinity to murine macrophages in cell culture and in vivo.

Results

Interestingly, we observed predominant NIR signals in the tumor site, which persisted for more than 48 h after single intravenous administration of the bioconjugate.

Conclusions

This result suggests that TLR4 targeting combined with NIR fluorescence imaging is a useful tool for cancer imaging. This imaging strategy could be used to detect cancerous tissue with the increased TAM content and evaluate the status of TLR4 signaling in solid tumors, ultimately impacting on the diagnostic and prognostic imaging of human cancers.

A Generic Coordination Assembly-Enabled Nanocoating of Individual Tumor Cells for Personalized Immunotherapy

A generic and effective tumor cells encapsulation strategy enabled by metal-organic coordination is developed to prepare a vaccine for personalized immunotherapy. Specifically, an epigallocatechin-3-gallate (EGCG)-Al(III) coordination layer is in situ formed onto individual living cells in aqueous phase and the process can be completed within an hour. 98% of proteins in the cells are entrapped within the microparticles, which are endowed with high antigens loading capacity. The microparticles enhance the uptake efficiency of antigens, protect antigens from degradation in vivo, and delay the retention time of antigens in the lymph nodes. Moreover, dendritic cells (DCs) activation is triggered by the microparticles, and simultaneously, the expression of costimulation marker on DCs and the production of Th1-related cytokines are significantly upregulated. Moreover, six kinds of tumor cells are utilized and successfully coated with the EGCG/Al(III) layer, suggesting the generalization of this strategy. More importantly, the microparticles exhibit a comparative antitumor effect with polyinosinic-polycytidylic acid (PolyI:C) in B16 pulmonary metastasis model. Overall, the encapsulation strategy enabled by metal-organic coordination can be potentially useful for personalized immunotherapy customized to individual patient's tumor cells.

Dietary flavonoids: Nano delivery and nanoparticles for cancer therapy

Application of nanotechnologies to cancer therapy might increase solubility and/or bioavailability of bioactive compounds of natural or synthetic origin and offers other potential benefits in cancer therapy, including selective targeting. In the present review we aim to evaluate in vivo studies on the anticancer activity of nanoparticles (NPs) obtained from food-derived flavonoids. From a systematic search a total of 60 studies were identified. Most of the studies involved the flavanol epigallocatechin-3-O-gallate and the flavonol quercetin, in both delivery and co-delivery (with anti-cancer drugs) systems. Moreover, some studies investigated the effects of other flavonoids, such as anthocyanins aglycones anthocyanidins, flavanones, flavones and isoflavonoids. NPs inhibited tumor growth in both xenograft and chemical-induced animal models of cancerogenesis. Encapsulation improved bioavailability and/or reduced toxicity of both flavonoids and/or co-delivered drugs, such as doxorubicin, docetaxel, paclitaxel, honokiol and vincristine. Moreover, flavonoids have been successfully applied in molecular targeted nanosystems. Selectivity for cancer cells involves pH- and/or reactive oxygen species-mediated mechanisms. Furthermore, flavonoids are good candidates as drug delivery for anticancer drugs in green synthesis systems. In conclusion, although human studies are needed, NPs obtained from food-derived flavonoids have promising anticancer effects in vivo.

Real-Time Fluorescence Imaging in Thoracic Surgery

Near-infrared (NIR) fluorescence imaging provides a safe and cost-efficient method for immediate data acquisition and visualization of tissues, with technical advantages including minimal autofluorescence, reduced photon absorption, and low scattering in tissue. In this review, we introduce recent advances in NIR fluorescence imaging systems for thoracic surgery that improve the identification of vital tissues and facilitate the resection of tumorous tissues. When coupled with appropriate NIR fluorophores, NIR fluorescence imaging may transform current intraoperative thoracic surgery methods by enhancing the precision of surgical procedures and augmenting postoperative outcomes through improvements in diagnostic accuracy and reductions in the remission rate.

Real-Time Imaging of Vaccine Biodistribution Using Zwitterionic NIR Nanoparticles

Efficient and timely delivery of vaccine antigens to the secondary lymphoid tissue is crucial to induce protective immune responses by vaccination. However, determining the longitudinal biodistribution of injected vaccines in the body has been a challenge. Here, the near-infrared (NIR) fluorescence imaging is reported that can efficiently enable the trafficking and biodistribution of vaccines in real time. Zwitterionic NIR fluorophores are conjugated on the surface of model vaccines and tracked the fate of bioconjugated vaccines after intradermal administration. Using an NIR fluorescence imaging system, it is possible to obtain time-course imaging of vaccine trafficking through the lymphatics, observing notable uptake in lymph nodes with minimal nonspecific tissue interactions. Flow cytometry analysis confirmed that the uptake in lymph nodes by antigen presenting cells was highly dependent on the hydrodynamic diameter of vaccines. These results demonstrate that the combination of a real-time NIR fluorescence imaging system and zwitterionic fluorophores is a powerful tool to determine the fate of vaccine antigens. Since such non-specific vaccine uptake causes serious adverse reactions, this method is not only useful for optimization of vaccine design, but also for safety evaluation of clinical vaccine candidates.

Carrier-Enhanced Anticancer Efficacy of Sunitinib-Loaded Green Tea-Based Micellar Nanocomplex beyond Tumor-Targeted Delivery

Although a few nanomedicines have been approved for clinical use in cancer treatment, that recognizes improved patient safety through targeted delivery, their improved efficacy over conventional drugs has remained marginal. One of the typical drawbacks of nanocarriers for cancer therapy is a low drug-loading capacity that leads to insufficient efficacy and requires an increase in dosage and/or frequency of administration, which in turn increases carrier toxicity. In contrast, elevating drug-loading would cause the risk of nanocarrier instability, resulting in low efficacy and off-target toxicity. This intractable drug-to-carrier ratio has imposed constraints on the design and development of nanocarriers. However, if the nanocarrier has intrinsic therapeutic effects, the efficacy would be synergistically augmented with less concern for the drug-to-carrier ratio. Sunitinib-loaded micellar nanocomplex (SU-MNC) was formed using poly(ethylene glycol)-conjugated epigallocatechin-3-O-gallate (PEG-EGCG) as such a carrier. SU-MNC specifically inhibited the vascular endothelial growth factor-induced proliferation of endothelial cells, exhibiting minimal cytotoxicity to normal renal cells. SU-MNC showed enhanced anticancer effects and less toxicity than SU administered orally/intravenously on human renal cell carcinoma-xenografted mice, demonstrating more efficient effects on anti-angiogenesis, apoptosis induction, and proliferation inhibition against tumors. In comparison, a conventional nanocarrier, SU-loaded polymeric micelle (SU-PM) comprised of PEG-b-poly(lactic acid) (PEG-PLA) copolymer, only reduced toxicity with no elevated efficacy, despite comparable drug-loading and tumor-targeting efficiency to SU-MNC. Improved efficacy of SU-MNC was ascribed to the carrier-drug synergies with the high-performance carrier of PEG-EGCG besides tumor-targeted delivery.

PEG-Derivatized Dual-Functional Nanomicelles for Improved Cancer Therapy

Polymeric micelles have attracted considerable attention for effective delivery of poorly water-soluble cancer drugs. Polyethylene glycol (PEG), which has been approved for human use by the US Food and Drug Administration, is the most commonly used hydrophilic component of polymeric micelles because it is biocompatible and biodegradable. One disadvantage of traditional polymeric micelles is that they include a large amount of inert carrier materials, which do not contribute to therapeutic activity but increase cost and toxicity risk. A better alternative may be "dual-functional" micellar carriers, in which the hydrophobic carrier material (conjugated to PEG) has intrinsic therapeutic activity that complements, or even synergizes with, the antitumor activity of the drug cargo. This review summarizes recent progress in the development of PEG-derivatized dual-functional nanomicelles and surveys the evidence of their feasibility and promise for cancer therapy.

Highly Water-Soluble Methotrexate-Polyethyleneglycol-Rhodamine Prodrug Micelle for High Tumor Inhibition Activity

Highly water-soluble prodrug micelle (50-fold compared with free MTX) of methotrexate-polyethyleneglycol-rhodamine (MTX-PEG-rhodamine) and MTX-mPEG was synthesized by the esterification reaction. The stability of the prodrug micelles was evaluated in phosphate buffer saline (PBS) with 10% fetal bovine serum (FBS). The tumor volume of the saline, MTX, and MTX-PEG-rhodamine groups was increased 3.7-fold, 2.8-fold, and 1.8-fold, respectively, compared with the initial tumor volume. TUNEL and drug distribution results further confirmed that the micelle of MTX-PEG-rhodamine possessed fewer side effects on the normal tissue compared with MTX. The prodrug micelle showed four advantages: retention of the drug activity site, higher water solubility of methotrexate (MTX), ease of preparation and application, and preferential accumulation in tumor tissues. These advantages of MTX-mPEG make it a promising drug delivery system (DDS) for clinical use.