Integrating Liquification of the Gelated Tumor Interstitium around Nanomedicines with Biconditional GD2-Targeting for Precise and Safe Chemotherapy.

The quick diffusion of nanomedicines in the polysaccharide-gel-filling tumor interstitium and precise active targeting are two major obstacles that have not yet been overcome. Here, a poly(L-glutamyl-L-lysine(EK) (p(EK))-camouflaged, doxorubicin (Dox)-conjugated nanomedicine is developed to demonstrate the underlying mechanism of zwitterionic shell in synchronous barrier-penetration and biconditional active targeting. The zwitterionic p(EK) shell liquifies its surrounding water molecules in the polysaccharide gel of tumor interstitium, leading to five times faster diffusion than the pegylated Doxil with similar size in tumor tissue. Its doped sulfonate groups lead to more precise active tumor-targeting than disialoganglioside (GD2) antibody by meeting the dual requirements of tumor microenvironment (TME) pH and overexpression of GD2 on tumor. Consequently, the concentrations of the nanomedicine in tumor are always higher than in life-supported organs in whole accumulation process, reaching over ten times higher Dox in GD2-overexpressing MCF-7 tumors than in life-supporting organs. Furthermore, the nanomedicine also avoids anti-GD2-like accumulation in GD2-expressing kidney in a mouse model. Thus, the nanomedicine expands the therapeutic window of Doxil by more than three times and eliminates tumors with negligible myocardial and acute toxicity. This new insight paves an avenue to design nanodelivery systems for highly precise and safe chemotherapy.

An Engineered Design of Self-Assembly Nanomedicine Guided by Molecular Dynamic Simulation for Photodynamic and Hypoxia-Directed Therapy.

To overcome the hypoxia barrier in tumor therapy, a hypoxia-activated prodrug of docetaxel (DTX-PNB) was synthesized and self-assembled with indocyanine green (ICG), forming a combination nanomedicine ISDNN. With the guidance of molecular dynamic simulation, the ISDNN construction could be accurately controlled, achieving uniform size distribution and high drug loading up to 90%. Within the hypoxic tumor environment, ISDNN exerted ICG-mediated photodynamic therapy and aggravated hypoxia to boost DTX-PNB activation for chemotherapy, enabling enhanced antitumor efficacy.

Chitosan-derived nanoparticles impede signal transduction in T790M lung cancer therapy.

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treated patients ultimately develop disease progression, about 50% of which are involved in the emergence of a p.Thr790Met (T790M) mutation acquiring drug resistance. In order to solve the aforementioned problem, a therapeutic nanoparticles DGA is developed to overcome EGFR-T790M resistance via downstream anti-apoptotic signal transduction blocking by a combination with persuading mitochondrial dysfunction and inhibiting miRNA expression. As the concept of design, chitosan-derived nanocarrier DCAFP, capable of persuading mitochondrial dysfunction, is demonstrated to convey gefitinib (GFT) and miR21 inhibitor (anti-miR21) to form DGA nanoparticles. The superior accumulation of antitumor therapeutics and synergistic blocking of downstream signal transduction by mitochondrial dysfunction and miRNA regulation lead to high sensitivity of DGA nanoparticles to EGFR-T790M mutated non-small cell lung cancer (NSCLC) cells with significant inhibition of tumor cell growth. The in vivo study demonstrates superior safety and antitumor efficacy of EGFRT790M mutated lung cancer mouse models. These results highlight the promise of DGA nanoparticles for enhancing GFT sensitivity to EGFRT790M NSCLC.

In Vitro Anticancer Activity of Nanoformulated Mono- and Di-nuclear Pt Compounds.

Nanoformulations of mononuclear Pt complexes cis-PtCl2 (PPh3 )2 (1), [Pt(PPh3 )2 (L-Cys)] ⋅ H2 O (3, L-Cys=L-cysteinate), trans-PtCl2 (PPh2 PhNMe2 )2 (4; PPh2 PhNMe2 =4-(dimethylamine)triphenylphosphine), trans-PtI2 (PPh2 PhNMe2 )2 (5) and dinuclear Pt cluster Pt2 (µ-S)2 (PPh3 )4 (2) have comparable cytotoxicity to cisplatin against murine melanoma cell line B16F10. Masking of these discrete molecular entities within the hydrophobic core of Pluronic® F-127 significantly boosted their solubility and stability, ensuring efficient cellular uptake, giving in vitro IC50 values in the range of 0.87-11.23 µM. These results highlight the potential therapeutic value of Pt complexes featuring stable Pt-P bonds in nanocomposite formulations with biocompatible amphiphilic polymers.

Structural Insights into the Host-Guest Complexation between ß-Cyclodextrin and Bio-Conjugatable Adamantane Derivatives.

Understanding the host-guest chemistry of α-/ß-/γ- cyclodextrins (CDs) and a wide range of organic species are fundamentally attractive, and are finding broad contemporary applications toward developing efficient drug delivery systems. With the widely used ß-CD as the host, we herein demonstrate that its inclusion behaviors toward an array of six simple and bio-conjugatable adamantane derivatives, namely, 1-adamantanol (adm-1-OH), 2-adamantanol (adm-2-OH), adamantan-1-amine (adm-1-NH2), 1-adamantanecarboxylic acid (adm-1-COOH), 1,3-adamantanedicarboxylic acid (adm-1,3-diCOOH), and 2-[3-(carboxymethyl)-1-adamantyl]acetic acid (adm-1,3-diCH2COOH), offer inclusion adducts with diverse adamantane-to-CD ratios and spatial guest locations. In all six cases, ß-CD crystallizes as a pair supported by face-to-face hydrogen bonding between hydroxyl groups on C2 and C3 and their adjacent equivalents, giving rise to a truncated-cone-shaped cavity to accommodate one, two, or three adamantane derivatives. These inclusion complexes can be terminated as (adm-1-OH)2⊂CD2 (1, 2:2), (adm-2-OH)3⊂CD2 (2, 3:2), (adm-1-NH2)3⊂CD2 (3, 3:2), (adm-1-COOH)2⊂CD2 (4, 2:2), (adm-1,3-diCOOH)⊂CD2 (5, 1:2), and (adm-1,3-diCH2COOH)⊂CD2 (6, 1:2). This work may shed light on the design of nanomedicine with hierarchical structures, mediated by delicate cyclodextrin-based hosts and adamantane-appended drugs as the guests.

Cyclodextrin-based host-guest complexes loaded with regorafenib for colorectal cancer treatment.

The malignancy of colorectal cancer (CRC) is connected with inflammation and tumor-associated macrophages (TAMs), but effective therapeutics for CRC are limited. To integrate therapeutic targeting with tumor microenvironment (TME) reprogramming, here we develop biocompatible, non-covalent channel-type nanoparticles (CNPs) that are fabricated through host-guest complexation and self-assemble of mannose-modified γ-cyclodextrin (M-γ-CD) with Regorafenib (RG), RG@M-γ-CD CNPs. In addition to its carrier role, M-γ-CD serves as a targeting device and participates in TME regulation. RG@M-γ-CD CNPs attenuate inflammation and inhibit TAM activation by targeting macrophages. They also improve RG's anti-tumor effect by potentiating kinase suppression. In vivo application shows that the channel-type formulation optimizes the pharmacokinetics and bio-distribution of RG. In colitis-associated cancer and CT26 mouse models, RG@M-γ-CD is proven to be a targeted, safe and effective anti-tumor nanomedicine that suppresses tumor cell proliferation, lesions neovascularization, and remodels TME. These findings indicate RG@M-γ-CD CNPs as a potential strategy for CRC treatment.

On the Single-Crystal Structure of Tenofovir Alafenamide Mono-Fumarate: A Metastable Phase Featuring a Mixture of Co-Crystal and Salt.

Tenofovir alafenamide (TAF) is a prodrug of tenofovir as a potent nucleotide reverse transcriptase inhibitor. It serves as the key component of Genvoya® for the first-line treatment of human immunodeficiency virus infection (HIV) and is the active component of Vemlidy® for the treatment of chronic hepatitis B. Vemlidy® is also a monotherapeutic regimen formulated as TAF hemifumarate (1; TAF:fumarate = 2:1). In this work, we report for the first time the single-crystal structure of TAF fumarate hemihydrate (2, TAF:fumarate:H2O = 2:2:1). Compound 2 is initially documented as a salt in which one proton of the fumaric acid migrates to the amine group of the adenine moiety in TAF. It was recently proposed that ca. 20-30% proton is transferred to the N atom on the aromatic adenine backbone. We herein provide definitive single-crystal X-ray diffraction results to confirm that 2, though phase pure, is formed as a mixture of co-crystal (75%) and salt (25%). It features two pairs of TAF fumarates, wherein one of the four H atoms on the fumaric acid is transferred to the N atom of the adjacent adenine moiety while the other three carboxylates remain in their intrinsic acid form. Compound 2 is a metastable phase during the preparation of 1 and can be isolated by halting the reaction during the refluxing of TAF and fumaric acid in acetonitrile (MeCN). Our report complements the previous characterizations of TAF monofumarate, and its elusive structural patterns are finally deciphered.

Design and tuning of ionic liquid-based HNO donor through intramolecular hydrogen bond for efficient inhibition of tumor growth.

Developing ionic liquid (IL) drugs broaden new horizons in pharmaceuticals. The tunable nature endows ILs with capacity to delivery active ingredients. However, the tunability is limited to screen ionic components, and none realizes the kinetic tuning of drug release, which is a key challenge in the design of IL drugs. Here, a series of ILs are developed using biocompatible ionic components, which realizes absorption of gaseous NO to yield IL-NONOates. These IL-NONOates serve as HNO donors to release active ingredient. The release kinetics can be tuned through configuring the geometric construction of ILs (release half-lives, 4.2 to 1061 min). Mechanism research indicates that the tunability depends on the strength of intramolecular hydrogen bond. Furthermore, the IL-based HNO donors exert pharmacological potential to inhibit tumor progression by regulating intratumoral redox state. Coupled with biosafety, these IL-based HNO donors with facile preparation and tunable functionalization can be promising candidates for pharmaceutical application.

Montmorillonite-Enveloped Zeolitic Imidazolate Framework as a Nourishing Oral Nano-Platform for Gastrointestinal Drug Delivery.

Oral administration of medicine faces physiological constraints imposed by the gastrointestinal tract (GIT) and simultaneously causes irritation to GI mucosa, which motivates us to pursue the innovation of a GI drug delivery system. Inspired by the mucosa-nutrient functions of Zinc element and smectite clay, a montmorillonite (MMT)-enveloped zeolitic imidazolate framework (M-ZIF-8) is developed in a successive one-pot fabrication of ZIF-8 encapsulated medicine, and followed MMT coating to yield a core-shell nanoplatform for GI drug delivery. ZIF-8 encapsulated medicines can maintain their intrinsic structure, and MMT layer potentiates mucous-adhesion and optimizes medicine release. Validated in gastritis and colitis models, M-ZIF-8 not only achieves efficient GI delivery of nonsteroidal anti-inflammatory drugs (NSAIDs) for inflammation inhibition, but also reduces the NSAIDs-induced GI irritation, promoting mucosal healing in GIT. Coupled with the facile construction and biocompatibility, M-ZIF-8 shows a significant advancement in GI drug delivery.

[Synthesis of folate modified chitosan-based nanomicelles and its in vitro anti-tumor activity].

OBJECTIVE: To design and synthesize folate-modified pH-responsive chitosan-based nanomicelles and investigate the in vitro anti-tumor activity of the drug-loaded micelles. METHODS: CHI-DMA was obtained by reductive amination reaction of aldehyde-based chitosan and hydrophilic amine compounds, and CHI-DMA-LA was obtained by condensation reaction with lauric acid; FA-CHI-DMA-LA was obtained after modification with folic acid (FA). The drug-loaded nanomicelles FA-CHI-DMA-LA/DOX were assembled by solvent change method. The physicochemical properties of polymers were characterized by hydrogen nuclear magnetic resonance and transmission electron microscope. The particle size and surface potential were determined by dynamic light scattering method. Folic acid access rate, doxorubicin (DOX) loading rate and entrapped efficiency were measured by UV-vis spectrophotometer. The drug release properties of DOX-loaded micelles in vitro were monitored by fluorescence spectrophotometer at different pHs (7.4, 6.5, 5.0). The cytotoxicity against human oral cancer KB cells was detected by MTT assay. Fluorescence microscope and flow cytometry were applied to investigate the phagocytosis of DOX-loaded micelles on KB cells. RESULTS: FA-CHI-DMA-LA was synthesized. The particle sizes of FA-CHI-DMA-LA-1 and FA-CHI-DMA-LA-2 micelles which used for the subsequent experiments were (73±14) nm and (106±15) nm, zeta potential were (15.59±1.98) mV and (21.20±2.35) mV, respectively. The drug loading rates of drug-loaded micelles FA-CHI-DMA-LA-1/DOX and FA-CHI-DMA-LA-2/DOX are (4.08±1.12)%and (4.12±0.44)%, respectively. In vitro drug release is pH-responsive, with cumulative release of DOX up to 37%and 36%at pH 5.0, which is about 1.5 times higher than that of pH 7.4. For FA-CHI-DMA-LA micelles with 1.25 to 125 µg/mL concentration, the survival rate of KB cells is more than 70%after incubation for 24 hours. The cell uptake of FA-CHI-DMA-LA/DOX micelles was enhanced compared to CHI-DMA-LA/DOX, and the cell uptake was higher in incubation without FA medium than that with FA. Compared with free DOX or CHI-DMA-LA/DOX, FA-CHI-DMA-LA/DOX nanomicelles showed higher cyctoxicity to KB cells, especially the FA-CHI-DMA-LA-2/DOX nanomicelles, the cell survival rate was about 17% after incubation for 24 hours. CONCLUSIONS: FA-modified chitosan-based nanomicelle with good biocompatibility was successfully prepared, which exhibits tumor microenvironmental pH responsive drug release and tumor targeting.

A supramolecular platform for controlling and optimizing molecular architectures of siRNA targeted delivery vehicles.

It requires multistep synthesis and conjugation processes to incorporate multifunctionalities into a polyplex gene vehicle to overcome numerous hurdles during gene delivery. Here, we describe a supramolecular platform to precisely control, screen, and optimize molecular architectures of siRNA targeted delivery vehicles, which is based on rationally designed host-guest complexation between a ß-cyclodextrin-based cationic host polymer and a library of guest polymers with various PEG shape and size, and various density of ligands. The host polymer is responsible to load/unload siRNA, while the guest polymer is responsible to shield the vehicles from nonspecific cellular uptake, to prolong their circulation time, and to target tumor cells. A series of precisely controlled molecular architectures through a simple assembly process allow for a rapid optimization of siRNA delivery vehicles in vitro and in vivo for therapeutic siRNA-Bcl2 delivery and tumor therapy, indicating the platform is a powerful screening tool for targeted gene delivery vehicles.

A versatile ultrafine and super-absorptive H+-modified montmorillonite: application for metabolic syndrome intervention and gastric mucosal protection.

Metabolic syndrome (MetS) includes central obesity, hypertension, insulin resistance, and dyslipidemia and is closely related to nonalcoholic fatty liver disease, atherosclerotic cardiovascular disease (CVD) and type 2 diabetes mellitus, involving multiple causative factors. Current drug therapies for intervention and amelioration of MetS are essential in clinical treatment of metabolic disease. In this report, we proposed an H+-modified montmorillonite (H-MMT) using an acid modification method with ultrafine structure and super absorption ability as a potential drug for MetS. Hamsters fed a high-fat diet were orally treated with H-MMT and simvastatin was applied as a control. H-MMT lowered lipids by decreasing intestinal absorption and promoting lipid excretion, subsequently preventing obesity, fatty liver, and hyperlipidemia. Moreover, H-MMT was significantly safer and better tolerated by the liver compared to simvastatin, which was hepatotoxic. In addition, we found that H-MMT had protective effects on gastric mucosal damage. Therefore, this versatile H-MMT provides a potential strategy to effectively improve MetS and provide gastric mucosal protection in clinical applications.

A zipped-up tunable metal coordinated cationic polymer for nanomedicine.

Incorporating metal elements into polymers is a feasible means to fabricate new materials with multiple functionalities. In this work, a metal coordinated cationic polymer (MCCP) was developed. Ferric ions were incorporated into the polyethyleneimine-ß-cyclodextrin (PC) polymer chain via coordination to produce a zipped-up polymer with a micro-ordered and macro-disordered topological structure. By varying the metal concentration, a tunable superstructure could be formed on the nano-templates via the "zipping" effect. In addition, the physicochemical properties of the assembly of MCCPs and nucleic acids were tailored by tuning the composition of the metal ions and polymers. The loading efficiency of Rhodamine-B by MCCPs was enhanced. The in vitro and in vivo results showed that the hybrid materials could be adjusted to deliver nucleic acids or small molecules with good performance and acquired the capacity of generating reactive oxygen species in tumor cells. Thus, the tunable and multifunctional MCCP system has great potential in nanomedicine and biomaterial science.

A Hybrid Eukaryotic-Prokaryotic Nanoplatform with Photothermal Modality for Enhanced Antitumor Vaccination.

Cytomembrane-derived nanoplatforms are an effective biomimetic strategy in cancer therapy. To improve their functionality and expandability for enhanced vaccination, a eukaryotic-prokaryotic vesicle (EPV) nanoplatform is designed and constructed by fusing melanoma cytomembrane vesicles (CMVs) and attenuated Salmonella outer membrane vesicles (OMVs). Inheriting the virtues of the parent components, the EPV integrates melanoma antigens with natural adjuvants for robust immunotherapy and can be readily functionalized with complementary therapeutics. In vivo prophylactic testing reveals that the EPV nanoformulation can be utilized as a prevention vaccine to stimulate the immune system and trigger the antitumor immune response, combating tumorigenesis. In the melanoma model, the poly(lactic-co-glycolic acid)-indocyanine green (ICG) moiety (PI)-implanted EPV (PI@EPV) in conjunction with localized photothermal therapy with durable immune inhibition shows synergetic antitumor effects as a therapeutic vaccine. The eukaryotic-prokaryotic fusion strategy provides new perspectives for the design of tumor-immunogenic, self-adjuvanting, and expandable vaccine platforms.

Bioengineering Bacterial Vesicle-Coated Polymeric Nanomedicine for Enhanced Cancer Immunotherapy and Metastasis Prevention.

We herein propose a bioengineering approach where bacterial outer membrane vesicles (OMVs) were coated on drug-loaded polymeric micelles to generate an innovative nanomedicine for effective cancer immunotherapy and metastasis prevention. Whereas OMVs could activate the host immune response for cancer immunotherapy, the loaded drug within polymeric micelles would exert both chemotherapeutic and immunomodulatory roles to sensitize cancer cells to cytotoxic T lymphocytes (CTLs) and to kill cancer cells directly. We demonstrated that the systemic injection of such a bioinspired immunotherapeutic agent would not only provide effective protective immunity against melanoma occurrence but also significantly inhibited tumor growth in vivo and extended the survival rate of melanoma mice. Importantly, the nanomedicine could also effectively inhibit tumor metastasis to the lung. The bioinspired immunomodulatory nanomedicine we have developed repurposes the bacterial-based formulation for cancer immunotherapy, which also defines a useful bioengineering strategy to the improve current cancer immunotherapeutic agents and delivery systems.

Reconstructed chitosan with alkylamine for enhanced gene delivery by promoting endosomal escape.

Poor buffering capacity of chitosan (CS) results in insufficient intracellular gene release which poses the major barrier in gene delivery. Herein, we reconstructed pristine CS with propylamine (PA), (diethylamino) propylamine (DEAPA), and N, N-dimethyl- dipropylenetriamine (DMAMAPA) to obtain a series of alkylamine-chitosan (AA-CS). The introduction of multiple amino groups with rational ratios functionally enhance the buffering capacity of AA-CS, among which DMAPAPA-CS showed buffering capacity of 1.58 times that of chitosan. The reconstructed AA-CS functionally enhance the ability of gene binding and endosomal escape. It was observed that the DMAPAPA-CS/pDNA complexes exhibit a notable gene delivery efficiency, which promotes the functionalization of loaded pDNA. Importantly, the in vivo delivery assay reveals that the deep penetration issue can be resolved using DMAPAPA-CS gene delivery vector. Finally, the DMAPAPA-CS is applied to deliver the therapeutic p53 gene in A549 bearing mice, showing efficient therapeutic potential for cancer.

Reverting chemoresistance of targeted agents by a ultrasoluble dendritic nanocapsule.

Malignancies treated by insoluble targeted agents show low dose exposure and therapeutic responses, therefore easily develop drug resistance. Nanoparticle-modified drugs might disrupt chemoresistance by increasing dose exposure and altering resistance pathways, as administrated via the intravenous route to maximize efficacy. Herein, we proposed a self-assembled nanocapsulation strategy to construct a nanocomplex with multiarm polymer and novel dendrimer series (MAP-mG3) for encapsulating insoluble inhibitors by nucleotide lock. MAP-mG3 delivering the mammalian target of rapamycin (mTOR) inhibitor OSI-027 (MAP-mG3/OSI-027) showed higher loading capacity, enhanced solubility, controlled release, and increased intracellular tumoral accumulation. MAP-mG3/OSI-027, more efficiently than the free targeted agents, attenuated mTOR phosphorylation and inhibited growth of pancreatic cancer cells. In addition, MAP-mG3/OSI-027 reverted chemoresistance to OSI-027 in drug resistance pancreatic cancer by increasing intracellular dose exposure, as well as regulating ABCB1 expression and compensatory pathways. The optimized nanocapsulation design provides an effective strategy to engineer and reactivate insoluble targeted agents for chemoresistant applications.

A Multifunctional Hybrid[4]arene-Based Macrocyclic Amphiphile: Self-Assembly, Tunable LCST Behavior, and Construction of Fluorescent Nanoparticles for Cell Imaging.

A novel macrocyclic amphiphile based on hybrid[4]arene containing tri(ethylene glycol) chains as the hydrophilic part and benzene rings as the hydrophobic part was synthesized. It self-assembled to produce nanoparticles and showed lower critical solution temperature behavior that was affected by its concentration and K+. Moreover, amphiphilic H can encapsulate dye G to form host-guest complexes H⊃G, accompanied by significant fluorescence enhancement. H⊃G can further self-assemble to form fluorescent nanoparticles that can be applied in cell imaging.

Enhanced antitumour effect for hepatocellular carcinoma in the advanced stage using a cyclodextrin-sorafenib-chaperoned inclusion complex.

Hepatocellular carcinoma (HCC) is a hypervascular tumour characterized by tumour-driven neovascularization. The degrees of blood oxygen saturation (DBOS), microvessel density (MVD) and tumour size (TS) are indicators in identifying the development stage of HCC. Herein, we proposed an HCC staging model using HepG2 tumour-bearing mice based on DBOS, MVD and TS. According to the patterns of these three criteria, HCC was classified into four stages: early, intermediate, advanced and end stages. The advanced stage was characterized by MVD of 50-90 (number per mm2), DBOS of 12-16% and TS of 250-600 mm3, which poses a critical challenge in HCC therapy. In order to efficiently control and treat HCC in the advanced stage, we developed a cyclodextrin (CD)-based chaperoned inclusion complex using Sorafenib (Sor), ß-CD and γ-CD (SCD) via the co-crystallization method. The structural study manifested that CDs could encapsulate Sor with the hydrophobic cavities at a 1 : 1 stoichiometry ratio. The crystallographic analysis indicated that Sor-ß-CD presented a diagonal stacking pattern, while Sor-γ-CD possessed a channel-type structure. The resultant chaperoned inclusion complexes significantly improved the solubility, dissolution rate and drug release of Sor, leading to superior pharmacokinetics, biodistribution and biosafety through oral administration. The antitumour effect was then evaluated on a mouse model with advanced HCC through oral administration and intratumour injection. The treatment involving the oral administration of SCDs showed a promising therapeutic effect on advanced HCC, which efficiently blocked angiogenesis and inhibited tumour progression. For the treatments using intratumour injections, only Sor-γ-CD exhibited a satisfactory anti-tumour effect with reduction in TS, MVD and DBOS. The enhanced therapeutic performance of Sor-γ-CD was attributed to its channel-type structure, which had an impact on the dissociation and release of the drug. Thus, Sor-γ-CD can be used as a potential pro-drug for clinical medicine and basic research to treat HCC.

A PEGylated megamer-based microRNA delivery system activatable by stepwise microenvironment stimulation.

We developed a biodegradable, oncosensitive, megamer-based delivery system for miRNA therapy. The miRNA nanotherapeutics, activatable by stepwise stimulation of acidity and reduction mimicking tumor microenvironment, efficiently improve liver-specific miR-122 expression, increasing the possibility of translational application of miR-122 therapy against liver cancer.