Nano drug delivery systems have made significant progress in delivering anticancer drugs camptothecin(CPT).However,many challenges for CPT delivery remain,including low drug loading efficiency,premature drug leakage,a...Nano drug delivery systems have made significant progress in delivering anticancer drugs camptothecin(CPT).However,many challenges for CPT delivery remain,including low drug loading efficiency,premature drug leakage,and poor cellular internalization.Herein,we report a novel dual-sensitive polypeptide-based micelle with remarkably high drug loading of CPT for cancer therapy.This self-assembled micelle possesses the following essential components for CPT:(1)pH-sensitive PEG(OHC-PEG-CHO)for prolonging blood circulation and allowing biocompatibility by shielding the cationic micelles,which can be detached under the tumor acidic microenvironment and facilitates the cellular uptake;(2)polypeptide polylysine-polyphenylalanine(PKF)synthesized via ring-opening polymerization for micelle formation and CPT analogue loading;(3)dimeric CPT(DCPT)with redox-sensitive linker for increasing CPT loading and ensuring drug release at tumor sites.Interestingly,the linear-like morphology of PEG-PKF/DCPT micelles was able to enhance their cellular internalization when compared with the spherical blank PKF micelles.Also,the anticancer efficacy of DCPT against lung cancer cells was significantly improved by the micelle formation.In conclusion,this work provides a promising strategy facilitating the safety and effective application of CPT in cancer therapy.展开更多
Most of the conventional chemotherapeutic agents used for cancer chemotherapy suffer from multidrug resistance of tumor cells and poor antitumor efficacy.Based on physiological differences between the normal tissue an...Most of the conventional chemotherapeutic agents used for cancer chemotherapy suffer from multidrug resistance of tumor cells and poor antitumor efficacy.Based on physiological differences between the normal tissue and the tumor tissue,one effective approach to improve the efficacy of cancer chemotherapy is to develop pH-sensitive polymeric micellar delivery systems.The copolymers with reversible protonationedeprotonation core units or acid-liable bonds between the therapeutic agents and the micelle-forming copolymers can be used to form pH-sensitive polymeric micelles for extracellular and intracellular drug smart release.These systems can be triggered to release drug in response to the slightly acidic extracellular fluids of tumor tissue after accumulation in tumor tissues via the enhanced permeability and retention effect,or they can be triggered to release drug in endosomes or lysosomes by pH-controlled micelle hydrolysis or dissociation after uptake by cells via the endocytic pathway.The pH-sensitive micelles have been proved the specific tumor cell targeting,enhanced cellular internalization,rapid drug release,and multidrug resistance reversal.The multifunctional polymeric micelles combining extracellular pH-sensitivity with receptor-mediated active targeting strategies are of great interest for enhanced tumor targeting.The micelles with receptor-mediated and intracellular pH targeting functions are internalized via receptor-mediated endocytosis followed by endosomal-pH triggered drug release inside the cells,which reverses multidrug resistance.The pH sensitivity strategy of the polymeric micelles facilitates the specific drug delivery with reduced systemic side effects and improved chemotherapeutical efficacy,and is a novel promising platform for tumor-targeting drug delivery.展开更多
Targeted drug delivery coupled with rapid drug release in cytoplasm is a powerful strategy to enhance efficacy and reduce off-target effects of anti-cancer drugs. Herein, we describe a dual-functional mixed micellar s...Targeted drug delivery coupled with rapid drug release in cytoplasm is a powerful strategy to enhance efficacy and reduce off-target effects of anti-cancer drugs. Herein, we describe a dual-functional mixed micellar system consisting of a pH-responsive copolymer D-α-tocopheryl polyethylene glycol 1000-block- poly-（β-amino ester） （TPGS-b-PBAE, TP） and AS1411 aptamer （Apt） decorated TPGS polymer （Apt-TPGS）, which recognizes the over-expressed nucleolin on the plasma membrane of cancer cells. The anti-cancer drug paclitaxel （PTX） was encapsulated in the Apt-mixed micelles, and these drug-loaded micelles had a suitable particle size and zeta potential of 116.3 nm ± 12.4 nm and -26.2 mV ±4.2 mV, respectively. PTX/Apt-mixed micelles were stable at pH 7.4, but they dissociated and quickly released the encapsulated PTX in a weakly acidic environment （pH 5.5）. Compared with non-Apt modified mixed micelles, more Apt-modified mixed micelles were internalized in SKOV3 ovarian cancer cells, whereas no significant difference in cellular uptake was observed in normal cells （LO2 cells）. The enhanced transmembrane ability of Apt-modified mixed micelles was achieved through Apt-nucleolin interaction. With a synergistic effect of cancer cell recognition and pH-sensitive drug release, we observed significantly increased cytotoxicity and G2/M phase arrest against SKOV3 cells by PTX/ Apt-mixed micelles. Intravenous administration of PTX/Apt-mixed micelles for 16 days significantly increased tumor accumulation of PTX, inhibited tumor growth, and reduced myelosuppression on tumor-bearing mice compared with free PTX injection. Therefore, this dual-functional Apt-mixed micellar system is a promising drug delivery system for targeted cancer therapy.展开更多
In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles...In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles were designed and fabricated to encapsulate doxorubicin(DOX) by combination of p H-sensitive amphiphilic polymer poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) with FA-conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide). The prepared micelles were characterized to have about 36 nm in diameter with narrow distribution, well-defined spherical shape observed under TEM and p H-responsive drug release behavior. Moreover, the tumor targeting ability of the FA-modified p H-sensitive polymeric micelles was demonstrated by the cellular uptake, in vitro cytotoxicity to FR-positive KB cells and in vivo real time near-infrared fluorescence imaging in KB tumor-bearing nude mice. The efficient drug delivery by the micelles was ascribed to the synergistic effects of FR-mediated targeting and p H-triggered drug release. In conclusion, the designed FR-targeted p H-sensitive polymeric micelles might be of great potential in tumor targeted delivery of water-insoluble anticancer drugs.展开更多
In the present study, we designed and fabricated pH-sensitive polymeric micelles based on the conjugate of poly（2-ethyl-2-oxazoline）-poly（D,L-lactide）（PEOz-PLA） with doxorubicin（PEOz-PLA-imi-DOX） to efficientl...In the present study, we designed and fabricated pH-sensitive polymeric micelles based on the conjugate of poly（2-ethyl-2-oxazoline）-poly（D,L-lactide）（PEOz-PLA） with doxorubicin（PEOz-PLA-imi-DOX） to efficiently inhibit tumor cell growth. Hence, PEOz-PLA-imi-DOX was successfully synthesized by connecting DOX to the hydrophobic end of pH-sensitive PEOz-PLA via acid cleavable benzoic imine linker and characterized by 1 H NMR spectrum and thin layer chromatography. The critical micelle concentration of PEOz-PLA-imi-DOX was determined to be（14.84±3.85） mg/L. The conjugate micelles（denoted as PP-DOX-PM） formed by PEOz-PLA-imi-DOX using film-hydration method were characterized to have a nano-scaled size of about 21 nm in diameter, and the drug loading content was 1.67%. PP-DOX-PM showed pH-dependent drug release behavior with gradually accelerated release of DOX with decrease of pH value, illustrating the micelles＇ distinguishing feature of endo/lysosomal pH from physiological pH by accelerating drug release. As anticipated, PP-DOX-PM maintained the cytotoxicity of DOX against MDA-MB-231 cells. Collectively, PP-DOX-PM might have great potential for effective suppression of tumor growth.展开更多
Nanoparticles armed with chemotherapy drug and fluorescence probe have become an effective anticancer strategy for their advantages in cancer diagnosis and treatment.However,fluorophore for diagnostic medicine with de...Nanoparticles armed with chemotherapy drug and fluorescence probe have become an effective anticancer strategy for their advantages in cancer diagnosis and treatment.However,fluorophore for diagnostic medicine with deep penetration depth and high resolution are still very rare,while rational designs are also required to improve the tumor retention and target-site drug delivery.Herein,a two-photon fluorophore with aggregation-induced emission and large two-photon absorption cross-section has been designed for two-photon bioimaging,and a novel theranostic nanoplatform is also constructed based on doxorubicin and the two-photon fluorophore conjugated copolymer,P(TPMA-co-AEMA)-PEI(DA)-Blink-PEG (PAEEBlink-DA).The micelles maintain a “stealth” property during blood circulation and is activated in the acidic tumor microenvironment,which triggers the charge-conversion and results in enhanced micellar internalization.Meanwhile,PAEMA chains can convert from hydrophobicity to hydrophilicity with accelerated drug release and particle size expansion.The enlarged particle size would potentially extend the retention time of these micelles.Moreover,a great AIE active two-photon bioimaging with tissue penetration depth up to 150 μm is observed and the in vivo biodistribution of nanoparticles can be traced.The in vivo antitumor results further indicate the obvious reduction of adverse effect and enhanced treatment effect of these micelles,proving that these PAEEBlink-DA micelles would be a potential candidate for tumor theranostic applications.展开更多
To guide the molecular design of the pH-sensitive triblock amphiphilic polymer MPEG-PAE-PLA and the for- mula design of its doxorubicine （DOX）-loaded micelles, dissipative particle dynamics （DPD） simulations are e...To guide the molecular design of the pH-sensitive triblock amphiphilic polymer MPEG-PAE-PLA and the for- mula design of its doxorubicine （DOX）-loaded micelles, dissipative particle dynamics （DPD） simulations are em- ployed to investigate the aggregation behaviors of the DOX-loaded micelles. The simulation results showed that the aggregate morphologies of micelles and DOX distribution are influenced by degree of polymerization of blocks, and the proposed structure of polymer is MPEG44-PAE3-PLA4. With different contents of polymer or DOX, differ- ent aggregate morphologies of the micelles, like microsphere, spindle/column, reticulation or lamella are observed. To prepare the micro-spherical DOX-loaded micelles, the polymer content is proposed as 10%--15%, and the DOX content less than 10%.展开更多
Supramolecular structures have received growing attention and been widely applied in many fields.Herein, we synthesized hydrophobic β-cyclodextrin-contained poly(β-amino ester)(PAE-β-CD) and hydrophilic adamantyl-t...Supramolecular structures have received growing attention and been widely applied in many fields.Herein, we synthesized hydrophobic β-cyclodextrin-contained poly(β-amino ester)(PAE-β-CD) and hydrophilic adamantyl-terminated poly(ethylene glycol)(PEG-AD) to form a supramolecular micelle via the host-guest interaction. The micelle displayed pH responsive structure change due to the transform of hydrophobic PAE core to hydrophilic form in weakly acid condition. After the anticancer drug curcumin(Cur) was loaded into the micelle, the drug release behavior of the Cur-loaded micelle was studied, and it turned out that the Cur-loaded supramolecular micelle could effectively unload the drug at pH 5.5.Furthermore, the antitumor efficiency of the Cur-loaded micelle was also examined both in vitro and in vivo, indicating considerable inhibition ratio as high as 62.14% against mouse sarcoma 180.展开更多
Photothermo-chemotherapy, as a new strategy for cancer treatment, incorporates the complementary advantages of photothermal therapy and chemotherapy. In this study, a pH-sensitive diblock copolymer poly（aspartic acid...Photothermo-chemotherapy, as a new strategy for cancer treatment, incorporates the complementary advantages of photothermal therapy and chemotherapy. In this study, a pH-sensitive diblock copolymer poly（aspartic acid-butanediamine）-poly（2- （diisopropylamino）ethyl methacrylate） （PAsp（DAB）-PDPA） was synthesized and self-assembled into doxorubicin-loaded micelle, which was further used as a template to form a gold nanoshell. After fitrther modification with poly（ethylene glycol）, the resulting nanoplatform provided good biocompatibility and desirable photo-thermal conversion efficiency to facilitate photothermal therapy. Meanwhile the nanoparticle also exhibited pH sensitivity, which prevented drug loss while circulating in the blood but enabled rapid drug release after endocytosis. An improved effect was achieved with the combination of photothermal therapy and chemotherapy. In addition, systemic delivery of the nanoplatform could be monitored by photoacoustic tomography. Thereby, this multifunctional nanoplatform would be highly potential for the diagnosis and therapy of cancer.展开更多
基金supported by the National Natural Science Foundation of China (51922111)the Science and Technology Development Fund, Macao SAR (File no. 0124/2019/A3)+1 种基金the University of Macao (File no. MYRG2022-00203-ICMS)Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials (2019B121205002)
文摘Nano drug delivery systems have made significant progress in delivering anticancer drugs camptothecin(CPT).However,many challenges for CPT delivery remain,including low drug loading efficiency,premature drug leakage,and poor cellular internalization.Herein,we report a novel dual-sensitive polypeptide-based micelle with remarkably high drug loading of CPT for cancer therapy.This self-assembled micelle possesses the following essential components for CPT:(1)pH-sensitive PEG(OHC-PEG-CHO)for prolonging blood circulation and allowing biocompatibility by shielding the cationic micelles,which can be detached under the tumor acidic microenvironment and facilitates the cellular uptake;(2)polypeptide polylysine-polyphenylalanine(PKF)synthesized via ring-opening polymerization for micelle formation and CPT analogue loading;(3)dimeric CPT(DCPT)with redox-sensitive linker for increasing CPT loading and ensuring drug release at tumor sites.Interestingly,the linear-like morphology of PEG-PKF/DCPT micelles was able to enhance their cellular internalization when compared with the spherical blank PKF micelles.Also,the anticancer efficacy of DCPT against lung cancer cells was significantly improved by the micelle formation.In conclusion,this work provides a promising strategy facilitating the safety and effective application of CPT in cancer therapy.
基金This work was financially supported from the National Nature Science Foundation of China(NO.81360483)from the Nature Science Foundation of Ningxia(No.NZ12193).
文摘Most of the conventional chemotherapeutic agents used for cancer chemotherapy suffer from multidrug resistance of tumor cells and poor antitumor efficacy.Based on physiological differences between the normal tissue and the tumor tissue,one effective approach to improve the efficacy of cancer chemotherapy is to develop pH-sensitive polymeric micellar delivery systems.The copolymers with reversible protonationedeprotonation core units or acid-liable bonds between the therapeutic agents and the micelle-forming copolymers can be used to form pH-sensitive polymeric micelles for extracellular and intracellular drug smart release.These systems can be triggered to release drug in response to the slightly acidic extracellular fluids of tumor tissue after accumulation in tumor tissues via the enhanced permeability and retention effect,or they can be triggered to release drug in endosomes or lysosomes by pH-controlled micelle hydrolysis or dissociation after uptake by cells via the endocytic pathway.The pH-sensitive micelles have been proved the specific tumor cell targeting,enhanced cellular internalization,rapid drug release,and multidrug resistance reversal.The multifunctional polymeric micelles combining extracellular pH-sensitivity with receptor-mediated active targeting strategies are of great interest for enhanced tumor targeting.The micelles with receptor-mediated and intracellular pH targeting functions are internalized via receptor-mediated endocytosis followed by endosomal-pH triggered drug release inside the cells,which reverses multidrug resistance.The pH sensitivity strategy of the polymeric micelles facilitates the specific drug delivery with reduced systemic side effects and improved chemotherapeutical efficacy,and is a novel promising platform for tumor-targeting drug delivery.
文摘Targeted drug delivery coupled with rapid drug release in cytoplasm is a powerful strategy to enhance efficacy and reduce off-target effects of anti-cancer drugs. Herein, we describe a dual-functional mixed micellar system consisting of a pH-responsive copolymer D-α-tocopheryl polyethylene glycol 1000-block- poly-（β-amino ester） （TPGS-b-PBAE, TP） and AS1411 aptamer （Apt） decorated TPGS polymer （Apt-TPGS）, which recognizes the over-expressed nucleolin on the plasma membrane of cancer cells. The anti-cancer drug paclitaxel （PTX） was encapsulated in the Apt-mixed micelles, and these drug-loaded micelles had a suitable particle size and zeta potential of 116.3 nm ± 12.4 nm and -26.2 mV ±4.2 mV, respectively. PTX/Apt-mixed micelles were stable at pH 7.4, but they dissociated and quickly released the encapsulated PTX in a weakly acidic environment （pH 5.5）. Compared with non-Apt modified mixed micelles, more Apt-modified mixed micelles were internalized in SKOV3 ovarian cancer cells, whereas no significant difference in cellular uptake was observed in normal cells （LO2 cells）. The enhanced transmembrane ability of Apt-modified mixed micelles was achieved through Apt-nucleolin interaction. With a synergistic effect of cancer cell recognition and pH-sensitive drug release, we observed significantly increased cytotoxicity and G2/M phase arrest against SKOV3 cells by PTX/ Apt-mixed micelles. Intravenous administration of PTX/Apt-mixed micelles for 16 days significantly increased tumor accumulation of PTX, inhibited tumor growth, and reduced myelosuppression on tumor-bearing mice compared with free PTX injection. Therefore, this dual-functional Apt-mixed micellar system is a promising drug delivery system for targeted cancer therapy.
基金National Natural Science Foundation of China(Grant No.81673366)。
文摘In order to enhance the targeted delivery of anticancer drugs by polymeric micelles, folic acid(FA), the ligand of folate receptor(FR) over-expressed in the most cancer cells, modified p H-sensitive polymeric micelles were designed and fabricated to encapsulate doxorubicin(DOX) by combination of p H-sensitive amphiphilic polymer poly(2-ethyl-2-oxazoline)-poly(D,L-lactide) with FA-conjugated poly(2-ethyl-2-oxazoline)-poly(D,L-lactide). The prepared micelles were characterized to have about 36 nm in diameter with narrow distribution, well-defined spherical shape observed under TEM and p H-responsive drug release behavior. Moreover, the tumor targeting ability of the FA-modified p H-sensitive polymeric micelles was demonstrated by the cellular uptake, in vitro cytotoxicity to FR-positive KB cells and in vivo real time near-infrared fluorescence imaging in KB tumor-bearing nude mice. The efficient drug delivery by the micelles was ascribed to the synergistic effects of FR-mediated targeting and p H-triggered drug release. In conclusion, the designed FR-targeted p H-sensitive polymeric micelles might be of great potential in tumor targeted delivery of water-insoluble anticancer drugs.
基金National Natural Science Foundation of China(Grant No.81673366)the National Key Science Research Program of China(973 Program,Grant No.2015CB932100)
文摘In the present study, we designed and fabricated pH-sensitive polymeric micelles based on the conjugate of poly（2-ethyl-2-oxazoline）-poly（D,L-lactide）（PEOz-PLA） with doxorubicin（PEOz-PLA-imi-DOX） to efficiently inhibit tumor cell growth. Hence, PEOz-PLA-imi-DOX was successfully synthesized by connecting DOX to the hydrophobic end of pH-sensitive PEOz-PLA via acid cleavable benzoic imine linker and characterized by 1 H NMR spectrum and thin layer chromatography. The critical micelle concentration of PEOz-PLA-imi-DOX was determined to be（14.84±3.85） mg/L. The conjugate micelles（denoted as PP-DOX-PM） formed by PEOz-PLA-imi-DOX using film-hydration method were characterized to have a nano-scaled size of about 21 nm in diameter, and the drug loading content was 1.67%. PP-DOX-PM showed pH-dependent drug release behavior with gradually accelerated release of DOX with decrease of pH value, illustrating the micelles＇ distinguishing feature of endo/lysosomal pH from physiological pH by accelerating drug release. As anticipated, PP-DOX-PM maintained the cytotoxicity of DOX against MDA-MB-231 cells. Collectively, PP-DOX-PM might have great potential for effective suppression of tumor growth.
基金supported by the National Natural Science Foundation of China (No.21502129)the National 111 Project of Introducing Talents of Discipline to Universities (No.B16033)+2 种基金China Postdoctoral Science Foundation Funded Project (Nos.2017M612956 and 2018T110969)the Key Technology Support Program of Sichuan Province (No.2016SZ0004)the State Key Laboratory of Polymer Materials Engineering (No.sklpme2018-3-05).
文摘Nanoparticles armed with chemotherapy drug and fluorescence probe have become an effective anticancer strategy for their advantages in cancer diagnosis and treatment.However,fluorophore for diagnostic medicine with deep penetration depth and high resolution are still very rare,while rational designs are also required to improve the tumor retention and target-site drug delivery.Herein,a two-photon fluorophore with aggregation-induced emission and large two-photon absorption cross-section has been designed for two-photon bioimaging,and a novel theranostic nanoplatform is also constructed based on doxorubicin and the two-photon fluorophore conjugated copolymer,P(TPMA-co-AEMA)-PEI(DA)-Blink-PEG (PAEEBlink-DA).The micelles maintain a “stealth” property during blood circulation and is activated in the acidic tumor microenvironment,which triggers the charge-conversion and results in enhanced micellar internalization.Meanwhile,PAEMA chains can convert from hydrophobicity to hydrophilicity with accelerated drug release and particle size expansion.The enlarged particle size would potentially extend the retention time of these micelles.Moreover,a great AIE active two-photon bioimaging with tissue penetration depth up to 150 μm is observed and the in vivo biodistribution of nanoparticles can be traced.The in vivo antitumor results further indicate the obvious reduction of adverse effect and enhanced treatment effect of these micelles,proving that these PAEEBlink-DA micelles would be a potential candidate for tumor theranostic applications.
文摘To guide the molecular design of the pH-sensitive triblock amphiphilic polymer MPEG-PAE-PLA and the for- mula design of its doxorubicine （DOX）-loaded micelles, dissipative particle dynamics （DPD） simulations are em- ployed to investigate the aggregation behaviors of the DOX-loaded micelles. The simulation results showed that the aggregate morphologies of micelles and DOX distribution are influenced by degree of polymerization of blocks, and the proposed structure of polymer is MPEG44-PAE3-PLA4. With different contents of polymer or DOX, differ- ent aggregate morphologies of the micelles, like microsphere, spindle/column, reticulation or lamella are observed. To prepare the micro-spherical DOX-loaded micelles, the polymer content is proposed as 10%--15%, and the DOX content less than 10%.
基金supported by the National Natural Science Foundation of China(No.81473173)
文摘Supramolecular structures have received growing attention and been widely applied in many fields.Herein, we synthesized hydrophobic β-cyclodextrin-contained poly(β-amino ester)(PAE-β-CD) and hydrophilic adamantyl-terminated poly(ethylene glycol)(PEG-AD) to form a supramolecular micelle via the host-guest interaction. The micelle displayed pH responsive structure change due to the transform of hydrophobic PAE core to hydrophilic form in weakly acid condition. After the anticancer drug curcumin(Cur) was loaded into the micelle, the drug release behavior of the Cur-loaded micelle was studied, and it turned out that the Cur-loaded supramolecular micelle could effectively unload the drug at pH 5.5.Furthermore, the antitumor efficiency of the Cur-loaded micelle was also examined both in vitro and in vivo, indicating considerable inhibition ratio as high as 62.14% against mouse sarcoma 180.
基金financially supported by the National Natural Science Foundation of China(No.U1401242)National Basic Research Program of China(No.2015CB755500)+1 种基金Natural Science Foundation of the Guangdong Province(No.2014A030312018)the Fundamental Research Funds for the Central Universities(Nos.17lgjc01 and 17lgpy08)
文摘Photothermo-chemotherapy, as a new strategy for cancer treatment, incorporates the complementary advantages of photothermal therapy and chemotherapy. In this study, a pH-sensitive diblock copolymer poly（aspartic acid-butanediamine）-poly（2- （diisopropylamino）ethyl methacrylate） （PAsp（DAB）-PDPA） was synthesized and self-assembled into doxorubicin-loaded micelle, which was further used as a template to form a gold nanoshell. After fitrther modification with poly（ethylene glycol）, the resulting nanoplatform provided good biocompatibility and desirable photo-thermal conversion efficiency to facilitate photothermal therapy. Meanwhile the nanoparticle also exhibited pH sensitivity, which prevented drug loss while circulating in the blood but enabled rapid drug release after endocytosis. An improved effect was achieved with the combination of photothermal therapy and chemotherapy. In addition, systemic delivery of the nanoplatform could be monitored by photoacoustic tomography. Thereby, this multifunctional nanoplatform would be highly potential for the diagnosis and therapy of cancer.
