Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jconrel.2021.10.015

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jconrel.2021.09.023

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/adma.202105254

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jacs.0c09029

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.202004180

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/ange.202004180

Language：English   Publishing type：Research paper (scientific journal)  

A major critical issue in systemically administered nanomedicines is nonspecific clearance by the liver sinusoidal endothelium, causing a substantial decrease in the delivery efficiency of nanomedicines into the target tissues. Here, we addressed this issue by in situ stealth coating of liver sinusoids using linear or two-armed poly(ethylene glycol) (PEG)–conjugated oligo(<sc>l</sc>-lysine) (OligoLys). PEG-OligoLys selectively attached to liver sinusoids for PEG coating, leaving the endothelium of other tissues uncoated and, thus, accessible to the nanomedicines. Furthermore, OligoLys having a two-armed PEG configuration was ultimately cleared from sinusoidal walls to the bile, while OligoLys with linear PEG persisted in the sinusoidal walls, possibly causing prolonged disturbance of liver physiological functions. Such transient and selective stealth coating of liver sinusoids by two-arm-PEG-OligoLys was effective in preventing the sinusoidal clearance of nonviral and viral gene vectors, representatives of synthetic and nature-derived nanomedicines, respectively, thereby boosting their gene transfection efficiency in the target tissues.

DOI： 10.1126/sciadv.abb8133

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsnano.9b09991

Language：English   Publishing type：Research paper (scientific journal)  

Therapeutic Polymersome Nanoreactors with Tumor-Specific Activable Cascade Reactions for Cooperative Cancer Therapy
Therapeutic nanoreactors are of increasing interest in precise cancer therapy, which have been explored to in situ produce therapeutic compounds from inert prodrugs or intrinsic molecules at the target sites. However, engineering a nanoreactor with tumor activable cascade reactions for efficient cooperative cancer therapy remains a great challenge. Herein, we demonstrate a polymersome nanoreactor with tumor acidity-responsive membrane permeability to activate cascade reactions for orchestrated cooperative cancer treatment. The nanoreactors are constructed from responsive polyprodrug polymersomes incorporating ultrasmall iron oxide nanoparticles and glucose oxidase in the membranes and inner aqueous cavities, respectively. The cascade reactions including glucose consumption to generate H2O2, accelerated iron ion release, Fenton reaction between H2O2 and iron ion to produce hydroxyl radicals (center dot OH), and center dot OH-triggered rapid release of parent drugs can be specifically activated by the tumor acidity-responsive membrane permeability. During this process, the orchestrated cooperative cancer therapy including starving therapy, chemodynamic therapy, and chemotherapy is realized for high-efficiency tumor suppression by the in situ consumed and produced compounds. The nanoreactor design with tumor-activable cascade reactions represents an insightful paradigm for precise cooperative cancer therapy.

DOI： 10.1021/acsnano.8b09082

Language：English   Publishing type：Research paper (scientific journal)  

Sustained and Bioresponsive Two‐Stage Delivery of Therapeutic miRNA via Polyplex Micelle‐Loaded Injectable Hydrogels for Inhibition of Intervertebral Disc Fibrosis

DOI： 10.1002/adhm.201800623

Language：English   Publishing type：Research paper (scientific journal)  

Precise tuning of disulfide crosslinking in mRNA polyplex micelles for optimizing extracellular and intracellular nuclease tolerability

DOI： 10.1080/1061186x.2018.1550646

Language：English   Publishing type：Research paper (scientific journal)  

Intracellular glutathione-depleting polymeric micelles for cisplatin prodrug delivery to overcome cisplatin resistance of cancers

DOI： 10.1016/j.jconrel.2018.01.019

Language：English   Publishing type：Research paper (scientific journal)  

Polymeric nanoreactors (NRs) have distinct advantages to improve chemical reaction efficiency, but the in vivo applications are limited by lack of tissue-specificity. Herein, novel glucose oxidase (GOD)-loaded therapeutic vesicular NRs (theraNR) are constructed based on a diblock copolymer containing poly(ethylene glycol) (PEG) and copolymerized phenylboronic ester or piperidine-functionalized methacrylate (P(PBEM-co-PEM)). Upon systemic injection, theraNR are inactive in normal tissues. At a tumor site, theraNR are specifically activated by the tumor acidity via improved permeability of the membranes. Hydrogen peroxide (H2O2) production by the catalysis of GOD in theraNR increases tumor oxidative stress significantly. Meanwhile, high levels of H2O2 induce self-destruction of theraNR releasing quinone methide (QM) to deplete glutathione and suppress the antioxidant ability of cancer cells. Finally, theraNR efficiently kill cancer cells and ablate tumors via the synergistic effect.

DOI： 10.1002/anie.201706964

Language：English   Publishing type：Research paper (scientific journal)  

Polymer Prodrug-Based Nanoreactors Activated by Tumor Acidity for Orchestrated Oxidation/Chemotherapy

DOI： 10.1021/acs.nanolett.7b03531

Language：English   Publishing type：Research paper (scientific journal)  

Therapeutic Vesicular Nanoreactors with Tumor‐Specific Activation and Self‐Destruction for Synergistic Tumor Ablation

DOI： 10.1002/ange.201706964

Language：English   Publishing type：Research paper (scientific journal)  

Light-Triggered Clustered Vesicles with Self-Supplied Oxygen and Tissue Penetrability for Photodynamic Therapy against Hypoxic Tumor
Smart nanocarriers are of particular interest for highly effective photodynamic therapy (PDT) in the field of precision nanomedicine. Nevertheless, a critical challenge still remains in the exploration of potent PDT treatment against hypoxic tumor. Herein, light-triggered clustered polymeric vesicles for photoinduced hypoxic tumor ablation are demonstrated, which are able to deeply penetrate into the tumor and simultaneously afford oxygen supply upon light irradiation. Hydrogen peroxide (H2O2) and poly(amidoamine) dendrimer conjugating chlorin e6/cypate (CC-PAMAM) are coassembled with reactive-oxygen-species-responsive triblock copolymer into the polymeric vesicles. Upon 805 nm irradiation, the vesicles exhibit the light-triggered thermal effect that is able to decompose H2O2 into O-2, which distinctly ensures the alleviation of tumor hypoxia at tumor. Followed by 660 nm irradiation, the vesicles are rapidly destabilized through singlet oxygen-mediated cleavage of copolymer under light irradiation and thus allow the release of photoactive CC-PAMAM from the vesicular chambers, followed by their deep penetration in the poorly permeable tumor. Consequently, the light-triggered vesicles with both self-supplied oxygen and deep tissue penetrability achieve the total ablation of hypoxic hypopermeable pancreatic tumor through photodynamic damage. These findings represent a general and smart nanoplatform for effective photoinduced treatment against hypoxic tumor.

DOI： 10.1002/adfm.201702108

Language：English   Publishing type：Research paper (scientific journal)  

Integrated Nanoparticles To Synergistically Elevate Tumor Oxidative Stress and Suppress Antioxidative Capability for Amplified Oxidation Therapy

DOI： 10.1021/acsami.7b08347

Language：English   Publishing type：Research paper (scientific journal)  

Smart nanocarriers attract considerable interest in the filed of precision nanomedicine. Dynamic control of the interaction between nano carriers and cells offers the feasibility that in situ activates cellular internalization at the targeting sites. Herein, we demonstrate a novel class of enzyme-responsive asymmetric polymeric vesicles self-assembled from matrix metalloproteinase (MMP)-cleavable peptide-linked triblock copolymer, poly(ethylene glycol)-GPLGVIZG-b-poly(epsilon-caprolactone)-b-poly(3-guanidinopropyl methacrylamide) (PEG-GPLGVRG-PCL-PGPMA), in which the cell-penetrating PGPMA segments asymmetrically distribute in the outer and inner shells with fractions of 9&#37; and 91&#37;, respectively. Upon treatment with MMP-2, to cleave the stealthy PEG Shell, the vesicles undergo morphological transformation into fused multicavity vesicles and small nanoparticles, accompanied by redistribution of PGPMA segments with 76&#37; exposed to the outside. The vesicles after dePEGylation show significantly increased cellular internalization efficiency (similar to 10 times) as compared to the original ones due to the triggered availability of cell-penetrating shells. The vesicles loading hydrophobic anticancer drug paclitaxel (PTX) in the membrane exhibit significantly enhanced cytotoxicity against MMP-overexpressing HT1080 cells and multicellular spheroids. The proposed vesicular system can serve as a smart nanoplatform for in situ activating intracellular drug delivery in MMP-enriched tumors.

DOI： 10.1021/acsami.7b02808

Language：English   Publishing type：Research paper (scientific journal)  

Radiosensitizer plays an important role in the cancer radiotherapy for efficient killing of hypoxic cancer cells at a low radiation dose. However, the commercially available small molecular radiosensitizers show low efficiency due to poor bioavailability in tumor tissues. In this report, we develop a novel amphiphilic block copolymer radiosensitizer, metronidazole-conjugated poly(ethylene glycol)-b-poly(gamma-propargyl-L-glutamate) (PEG-b-P(PLG-g-MN)), which can be self assembled into core shell micelles (MN-Micelle) with an optimal size of similar to 60 nm in aqueous solution. In vitro cytotoxicity evaluation indicated that MN-Micelle sensitized the hypoxic cancer cells more efficiently under radiation with the sensitization enhancement ratio (SER) of 1.62 as compared with that of commercially available sodium glycididazole (GS; SER = 1.17) at the metronidazole-equivalent concentration of 180 mu g/mL. Upon intravenous injection of MN-Micelle into the tumor-bearing mice, high tumor deposition was achieved, which finally suppressed tumor growth completely after electron beam radiation at a low radiation dose of 4 Gy. MN-Micelle with outstanding performance as an in vivo radiosensitizer holds great potentials for translation into radiotherapy application.

DOI： 10.1021/acsmacrolett.7b00196

Language：English   Publishing type：Research paper (scientific journal)  

Modular Design and Facile Synthesis of Enzyme-Responsive Peptide-Linked Block Copolymers for Efficient Delivery of Doxorubicin

DOI： 10.1021/acs.biomac.6b00997

Language：English   Publishing type：Research paper (scientific journal)  

Finely Tuned Thermo-Responsive Block Copolymer Micelles for Photothermal Effect-Triggered Efficient Cellular Internalization
Although biodegradable amphiphilic block copolymer micelles have been widely applied in the clinical applications as drug delivery nanocarriers, low-efficiency cellular internalization frequently reduces therapeutic efficacy of the loaded drugs. Here, photothermal effect-promoted cellular internalization of finely tuned thermo-responsive amphiphilic biodegradable block copolymer nanocarriers via noninvasive stimuli of near-infrared (NIR) light irradiation is demonstrated. Amphiphilic block copolymers, poly(epsilon-caprolactone)-block-poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) (PCL-b-P(NIPAM-co-DMA)), are prepared with finely tuned compositions of P(NIPAM-co-DMA) for desirable lower critical solution temperature of the block copolymer micelles in aqueous solution. The block copolymers are then used to co-encapsulate doxorubicin and indocyanine green, which show high encapsulation efficiency and significant photothermal effect upon exposure to NIR light irradiation. The photo thermal effect-induced collapse and hydrophilic-to-hydrophobic transition of P(NIPAM-co-DMA) shells significantly enhance the interactions between drug-loaded micelles and cell membranes, which dramatically promote the cellular internalization of the micelles and therapeutic efficacy of loaded anticancer drugs.

DOI： 10.1002/mabi.201600119

Language：English   Publishing type：Research paper (scientific journal)  

Direct encapsulation of hydrophobic drugs into amphiphilic block copolymer micelles is frequently subjected to low drug loading efficiency (DLE) and loading content (DLC), as well as lower micellar stability and uncontrollable drug release. In this report, we prepare the copolymer prodrugs (PPEMA-co-PCPTM) via reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(piperidin-1-yl)ethyl methacrylate (PEMA) and reduction-responsive CPT monomer (CPTM), which were quantitatively encapsulated into poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PEG-b-PCL) micelles. The polymer prodrug-loaded nanoparticles showed high stability for a long time in aqueous solution or blood serum and even maintain similar size after a lyophilization-dissolution cycle. The tumoral pH (similar to 6.8)-responsive properties of PPEMA segments endow the micellar cores with triggered transition from neutral to positively charged and swellable properties. The PEG-b-PCL nanoparticles loading polymer prodrugs (PPEMA-b-PCPTM) eliminated burst drug release. Simultaneously, CPT drug release can be triggered by reductive agents and solution pH. At pH 6.8, efficient cellular internalization was achieved due to positively charged cores of the nanoparticles. As compared with nanoparticles loading PCPTM, higher cytotoxicity was observed by the nanoparticles loading PPEMA-b-PCPTM at pH 6.8. Further multicellular tumor spheroid (MCTs) penetration and growth suppression studies demonstrated that high-efficiency penetration capability and significant size shrinkage of MCTs were achieved after treatment by PPEMA-b-PCPTM-loaded nanoparticles at pH 6.8. Therefore, the responsive polymer prodrug encapsulation strategy represents an effective method to overcome the disadvantages of common hydrophobic drug encapsulation approaches by amphiphilic block copolymer micelles and simultaneously endows the nanoparticles with responsive drug release behaviors as well as enhanced cellular internalization and tumor penetration capability.

DOI： 10.1021/acsami.5b12227

Language：English   Publishing type：Research paper (scientific journal)  

One of distinct features in tumor tissues is the elevated concentration of reactive oxygen species (ROS) during tumor immortality, proliferation and metastasis. However, ROS-responsive materials are rarely utilized in the field of in vivo tumoral ROS-responsive applications due to the fact that the intrinsic ROS level in the tumors could not escalate to an adequate level that the developed materials can possibly respond. Herein, palmitoyl ascorbate (PA) as a prooxidant for hydrogen peroxide (H2O2) production in tumor tissue is strategically compiled into a H2O2-responsive camptothecin (CPT) polymer prodrug micelle, which endowed the nanocarriers with self-sufficing H2O2 stimuli in tumor tissues. Molecular oncology manifests the hallmarks of tumoral physiology with deteriorating propensity in eliminating hazardous ROS. H2O2 production was demonstrated to specifically sustain in tumors, which not only induced tumor cell apoptosis by elevated oxidation stress but also served as autochthonous H2O2 resource to trigger CPT release for chemotherapy. Excess H2O2 and released CPT could penetrate into cells efficiently, which showed synergistic cytotoxicity toward cancer cells. Systemic therapeutic trial revealed potent tumor suppression of the proposed formulation via synergistic oxidation-chemotherapy. This report represents a novel nanomedicine platform combining up-regulation of tumoral H2O2 level and self-sufficing H2O2-responsive drug release to achieve novel synergistic oxidation-chemotherapy. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jconrel.2016.01.029

Language：English   Publishing type：Research paper (scientific journal)  

Endogenous Stimuli-Sensitive Multistage Polymeric Micelleplex Anticancer Drug Delivery System for Efficient Tumor Penetration and Cellular Internalization
To efficiently deliver anticancer drugs to the entire tumor tissue and cancer cells, an endogenous stimuli-sensitive multistage polymeric micelle-plex drug delivery system is developed via electrostatic complexation between poly(ethylene glycol)-block-poly[(N'-dimethylmaleoyl-2-aminoethyl)aspartamide]-block-poly(epsilon-caprolactone) (PEG-b-PAsp(EDA-DM)-b-PCL) triblock copolymer micelles and cisplatin prodrug (Pt(IV))-conjugated cationic poly(amidoamine) dendrimers (PAMAM-Pt(IV)). The micelleplexes maintain structural stability at pH 7.4 ensuring long blood circulation and high tumor accumulation level, while they exhibit triggered release of secondary PAMAM.Pt( IV) dendrimer nanocarriers at tumoral acidity (approximate to pH 6.8) due to acid-labile charge-reversal properties of PAsp(EDA-DM) component under mildly acidic condition. The released PAMAM delivery nanocarriers with small size and slightly positive charges exhibit significantly deep tumor tissue penetration and efficient cellular internalization, followed by release of active cisplatin anticancer drug in intracellular reducing medium. In vivo investigation reveals that the Pt(IV)-loading micelleplexes significantly suppress tumor growth via intravenous injection due to synergistic effect of long circulation in bloodstream, high tumor accumulation, deep tumor tissue penetration, and efficient cellular internalization. Thus, the micelleplexes with stimuli-responsive multistage release feature show great potentials for better therapeutic efficacy of cancer especially through enhanced tumor penetration and cellular internalization.

DOI： 10.1002/adhm.201500379

Language：English   Publishing type：Research paper (scientific journal)  

A Near-Infrared Photothermal Effect-Responsive Drug Delivery System Based on Indocyanine Green and Doxorubicin-Loaded Polymeric Micelles Mediated by Reversible Diels-Alder Reaction
Near-infrared light (NIR) possesses great advantages for light-responsive controllable drug release, such as deep tissue penetration and low damage to healthy tissues. Herein, a NIR-responsive drug delivery system is developed based on a NIR dye, indocyanine green (ICG), and anticancer drug, doxorubicin (DOX)-loaded thermoresponsive block copolymer micelles, in which the drug release can be controlled via NIR irradiation. First, block copolymers, poly(oligo(ethylene glycol) methacrylate)-block-poly(furfuryl methacrylate) (POEGMA-b-PFMA), are synthesized by sequential reversible addition-fragmentation chain-transfer (RAFT) polymerization, followed by modification with N-octyl maleimide through Diels-Alder (DA) reaction to produce POEGMA-b-POMFMA. The self-assembly of POEGMA-b-POMFMA by nanoprecipitation in aqueous solution affords the polymeric micelles which are used to simultaneously encapsulate ICG and DOX. Upon irradiation by NIR light (805 nm), the loaded DOX is released rapidly from the micelles due to partial retro DA reaction and local temperature increase-induced faster drug diffusion by the photothermal effect. Cytotoxicity evaluation and intracellular distribution observation demonstrate significant synergistic effects of NIR-triggered drug release, photothermal, and chemotherapy toward cancer cells under NIR irradiation.

DOI： 10.1002/marc.201500337

Language：English   Publishing type：Research paper (scientific journal)  

Endosomal-escape polymers based on multicomponent reaction-synthesized monomers integrating alkyl and imidazolyl moieties for efficient gene delivery

DOI： 10.1021/acsmacrolett.5b00615

Language：English   Publishing type：Research paper (scientific journal)  

Simultaneous achievement of prolonged retention in blood circulation and efficient gene transfection activity in target tissues has always been a major challenge hindering in vivo applications of nonviral gene vectors via systemic administration. Herein, we constructed novel rod-shaped ternary polyplex micelles (TPMs) via complexation between the mixed block copolymers of poly(ethylene glycol)-b-poly{N'-[N-(2-aminoethyl)-2-aminoethyl] aspartamide} (PEG-b-PAsp(DET)) and poly(N-isopropylacrylamide)-b-PAsp(DET) (PNIPAM-b-PAsp (DET)) and plasmid DNA (pDNA) at room temperature, exhibiting distinct temperature-responsive formation of a hydrophobic intermediate layer between PEG shells and pDNA cores through facile temperature increase from room temperature to body temperature (similar to 37 degrees C). As compared with binary polyplex micelles of PEG-b-PAsp(DET) (BPMs), TPMs were confirmed to condense pDNA into a more compact structure, which achieved enhanced tolerability to nuclease digestion and strong counter polyanion exchange. In vitro gene transfection results demonstrated TPMs exhibiting enhanced gene transfection efficiency due to efficient cellular uptake and endosomal escape. Moreover, in vivo performance evaluation after intravenous injection confirmed that TPMs achieved significantly prolonged blood circulation, high tumor accumulation, and promoted gene expression in tumor tissue. Moreover, TPMs loading therapeutic pDNA encoding an anti-angiogenic protein remarkably suppressed tumor growth following intravenous injection into H22 tumor-bearing mice. These results suggest TPMs with PEG shells and facilely engineered intermediate barrier to inner complexed pDNA have great potentials as systemic nonviral gene vectors for cancer gene therapy. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jconrel.2015.04.024

Language：English   Publishing type：Research paper (scientific journal)  

Safe and high-efficiency gene therapy for nucleus pulposus (NP) regeneration was urgently desired to treat disc degeneration-associated diseases. In this work, an efficient nonviral cationic block copolymer gene delivery system was used to deliver therapeutic plasmid DNA (pDNA), which was prepared via complexation between the mixed cationic block copolymers, poly(ethylene glycol)-block-poly{N-[N-(2-aminoethyl)-2-aminoehtyl]aspartamide) IPEG-b-PAsp(DET)] and poly(N-isopropylacrylamide)-block-PAsp(DET) [PNIPAM-b-PAsp(DET)], and pDNA at 25 degrees C. The mixed polyplex micelles (MPMs) containing heterogeneous coronas with hydrophobic and hydrophilic microdomains coexisting could be obtained upon heating from 25 to 37 degrees C, which showed high tolerability against nuclease and strong resistance towards protein adsorption. The gene transfection efficiency of MPMs in NP cells was significantly higher than that of regular polyplex micelles prepared from sole block copolymer of PEG-b-PAsp(DET) (SPMs) in in vitro and in vivo evaluation due to the synergistic effect of improved colloidal stability and low cytotoxicity. High expression of heme oxygenase-1 (HO-1) in NP cells transfected by MPMs loading HO-1 pDNA significantly decreased the expression activity of matrix metalloproteinases 3 (MMP-3) and cyclooxygenase-2 (COX-2) induced by interleukin-1 beta (IL-1 beta), and simultaneously increased the NP phenotype-associated genes such as aggrecan, type II collagen, and SOX-9. Moreover, the therapeutic effects of MPMs loading pDNA were tested to treat disc degeneration induced by stab injury. The results demonstrated that administration of HO-1 pDNA carried by MPMs in rat tail discs apparently reduced inflammatory responses induced by need stab and increased glycosaminoglycan (GAG) content, finally achieving better therapeutic efficacy as compared with SPMs. Consequently, MPMs loading HO-1 pDNA were demonstrated to be potential as a safe and high-efficiency nonviral gene delivery system for retarding or regenerating the degenerative discs. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biomaterials.2015.02.024

Language：English   Publishing type：Research paper (scientific journal)  

Adequate retention in blood circulation is a prerequisite for construction of gene delivery carriers for systemic applications. The stability of gene carriers in the bloodstream requires them to effectively resist protein adsorption and maintain small size in the bloodstream avoiding dissociation, aggregation, and nuclease digestion under salty and proteinous medium. Herein, a mixture of two block catiomers consisting of the same cationic block, poly{N-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} (PAsp(DET)), but varying shell-forming blocks, poly[2-(2-methoxyethoxy) ethyl methacrylate] (PMEO(2)MA), and poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA), was used to complex with plasmid DNA (pDNA) to fabricate polyplex micelles with mixed shells (MPMs) at 20 degrees C. The thermoresponsive property of PMEO(2)MA allows distinct phase transition from hydrophilic to hydrophobic by increasing incubation temperature from 20 to 37 degrees C, which results in a distinct heterogeneous corona containing hydrophilic and hydrophobic regions at the surface of the MPMs. Subsequent study verified that this transition promoted further condensation of pDNA, thereby giving rise to improved complex and colloidal stability. The proposed system has shown remarkable stability in salty and proteinous solution and superior tolerance to nuclease degradation. As compared with polyplex micelles formed from single POEGMA-b-PAsp(DET) block copolymer, in vivo circulation experiments in the bloodstream further confirmed that the retention time of MPMs was prolonged significantly. Moreover, the proposed system exhibited remarkably high cell transfection activity especially at low N/P ratios and negligible cytotoxicity and thus portends promising utility for systemic gene therapy applications.

DOI： 10.1021/bm500532x