Cell-penetrating peptides(CPPs)have been widely used to enhance the membrane transloca-tion of various carriers for many years,but the non-specificity of CPPs seriously limits their utility in vivo.In this study,chole...Cell-penetrating peptides(CPPs)have been widely used to enhance the membrane transloca-tion of various carriers for many years,but the non-specificity of CPPs seriously limits their utility in vivo.In this study,cholesterol-anchored,reduction-sensitive PEG(first synthesized by our laboratory)was applied to develop a co-modified liposome with improved tumor targeting.Following optimization of the formulation,the in vitro and in vivo properties of the co-modified liposome were evaluated.The co-modified liposome had a much lower cellular uptake and tumor spheroid uptake,but a much higher tumor accumulation compared to CPP-modified liposome,indicating the non-specific penetration of CPPs could be attenuated by the outer PEG coating.With the addition of exogenous reducing agent,both the in vitro and in vivo cellular uptake was markedly increased,demonstrating that the reduction-sensitive PEG coating achieved a controllable detachment from the surface of liposomes and did not affect the penetrating abilities of CPPs.The present results demonstrate that the combination of cholestervsitive PEG and CPPs is an ideal alternative for the application of CPP-modified carriers in vivo.展开更多
Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect pene...Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect penetration abilities of nanostructured lipid carriers（NLC）. Real--time penetration of folate--or cell penetrating peptide（CPP）-modified NLC was evaluated using a multicellular tumor spheroid（MTS） established by stacking culture method as an in vitro testing platform. The results suggested that CPP modification had a better penetration behavior both on penetration depth and intensity compared with folate-modified NLC at the early stage of penetration process.展开更多
The dense extracellular matrix and high interstitial fluid pressure of tumor tissues prevent the ability of anti-tumor agents to penetrate deep into the tumor parenchyma for treatment effects. C-end rule(CendR) peptid...The dense extracellular matrix and high interstitial fluid pressure of tumor tissues prevent the ability of anti-tumor agents to penetrate deep into the tumor parenchyma for treatment effects. C-end rule(CendR) peptides can enhance the permeability of tumor blood vessels and tumor tissues via binding to neuropilin-1(NRP-1), thus aiding in drug delivery. In this study, we selected one of the CendR peptides(sequence RGERPPR) as the parent L-peptide and substituted D-amino acids for the L-amino acids to synthesize its inverso peptide D(RGERPPR). We investigated the NRP-1 binding activity and tumorpenetrating ability of D(RGERPPR). We found that the binding affinity of D(RGERPPR) with NRP-1 and the cellular uptake was significantly higher than that of RGERPPR. Evans Blue tests revealed that D(RGERPPR) exhibited improved tumor-penetrating ability in C6, U87 and A549 tumor-bearing nude mice. Using nude mice bearing A549 xenograft tumors as a model, we found that the rate of tumor growth in the group co-administered with D(RGERPPR) and gemcitabine(Gem) was significantly lower than the gemcitabine-treated group with a tumor suppression rate(TSR%) of 55.4%. Together, our results demonstrate that D(RGERPPR) is a potential tumor-penetrating peptide.展开更多
Tumor penetration is important for effectively tumor targeting drug delivery.Recently,many researches are published to overcome the barriers that restrict tumor penetration and improve drug delivery efficiency.In the ...Tumor penetration is important for effectively tumor targeting drug delivery.Recently,many researches are published to overcome the barriers that restrict tumor penetration and improve drug delivery efficiency.In the mini review,we first analyzed the barriers influence the tumor penetration,including tumor microenvironment barriers,nanoparticle properties,and interaction barriers between tumor and nanoparticles.To overcome the barrier,several strategies are developed,including modulating tumor microenvironment,changing particle size,transcytosis enabled tumor penetration,cell penetrating peptide modification and overcoming binding site barrier,which could effectively improve tumor penetration,and finally enhance tumor treatment outcome.展开更多
Drug resistance renders standard chemotherapy ineffective in the treatment of connective tissue growth factor （CTGF）-overexpressing breast cancer. By co-embedding the breast tumor cell-penetrating peptide （PEGA-pVE...Drug resistance renders standard chemotherapy ineffective in the treatment of connective tissue growth factor （CTGF）-overexpressing breast cancer. By co-embedding the breast tumor cell-penetrating peptide （PEGA-pVEC） and hyaluronic acid （HA） as a targeting media, novel cascaded targeting nanoparficles （HACT NPs） were created on a rattle mesoporous silica （rmSiO2） scaffold for the pinpoint delivery of siRNAs along with an anticancer drug, aiming at overcoming the drug resistance of CTGF-overexpressing breast cancer in vivo. The targeting nanoparticles selectively accumulated in the vasculature under the guidance of the PEGA-pVEC peptide, cascaded by receptor-mediated endocytosis with the aid of another targeting agent, HA, presenting a greater in vivo tumor targeting ability than single targeting ligand vectors. In addition, an HA shell prevented the leakage of therapeutic drugs during the cargo transport process, until the hyaluronidase （HAase）-triggered degradation upon lysosomes entering, guaranteeing a controllable drug release inside the target cells. When the protective shell disintegrates, the released siRNA took charge to silence the gene associated with drug resistance, CTGF, thus facilitating doxorubicin-induced apoptosis. The cascaded targeting media （PEGA-pVEC and HA） advances precision-guided therapy in vivo, while the encapsulation of siRNAs into a chemotherapy drug delivery system provides an efficient strategy for the treatment of drug resistance cancers.展开更多
基金The work was funded by the National Natural Science Foundation of China(81373337)the National Basic Research Program of China(973 Program,2013CB932504).
文摘Cell-penetrating peptides(CPPs)have been widely used to enhance the membrane transloca-tion of various carriers for many years,but the non-specificity of CPPs seriously limits their utility in vivo.In this study,cholesterol-anchored,reduction-sensitive PEG(first synthesized by our laboratory)was applied to develop a co-modified liposome with improved tumor targeting.Following optimization of the formulation,the in vitro and in vivo properties of the co-modified liposome were evaluated.The co-modified liposome had a much lower cellular uptake and tumor spheroid uptake,but a much higher tumor accumulation compared to CPP-modified liposome,indicating the non-specific penetration of CPPs could be attenuated by the outer PEG coating.With the addition of exogenous reducing agent,both the in vitro and in vivo cellular uptake was markedly increased,demonstrating that the reduction-sensitive PEG coating achieved a controllable detachment from the surface of liposomes and did not affect the penetrating abilities of CPPs.The present results demonstrate that the combination of cholestervsitive PEG and CPPs is an ideal alternative for the application of CPP-modified carriers in vivo.
基金National key Basic Research Program(Grant No.2013CB932501)National Natural Science Foundation of China(Grant No.81273454 and 81473156)+1 种基金Beijing National Science Foundation(Grant No.7132113)Doctoral Foundation of the Ministry of Education(Grant No.20130001110055)
文摘Surface modification may have important influences on the penetration behavior of nanoscale drug delivery system. In the present study, we mainly focused on whether cell targeting or cell penetration could affect penetration abilities of nanostructured lipid carriers（NLC）. Real--time penetration of folate--or cell penetrating peptide（CPP）-modified NLC was evaluated using a multicellular tumor spheroid（MTS） established by stacking culture method as an in vitro testing platform. The results suggested that CPP modification had a better penetration behavior both on penetration depth and intensity compared with folate-modified NLC at the early stage of penetration process.
基金supported by the National Science Foundation of China (Grant Nos.81473148 and 81690263)the Foundation Program of Key Laboratory of Smart Drug Delivery of the Ministry of Education
文摘The dense extracellular matrix and high interstitial fluid pressure of tumor tissues prevent the ability of anti-tumor agents to penetrate deep into the tumor parenchyma for treatment effects. C-end rule(CendR) peptides can enhance the permeability of tumor blood vessels and tumor tissues via binding to neuropilin-1(NRP-1), thus aiding in drug delivery. In this study, we selected one of the CendR peptides(sequence RGERPPR) as the parent L-peptide and substituted D-amino acids for the L-amino acids to synthesize its inverso peptide D(RGERPPR). We investigated the NRP-1 binding activity and tumorpenetrating ability of D(RGERPPR). We found that the binding affinity of D(RGERPPR) with NRP-1 and the cellular uptake was significantly higher than that of RGERPPR. Evans Blue tests revealed that D(RGERPPR) exhibited improved tumor-penetrating ability in C6, U87 and A549 tumor-bearing nude mice. Using nude mice bearing A549 xenograft tumors as a model, we found that the rate of tumor growth in the group co-administered with D(RGERPPR) and gemcitabine(Gem) was significantly lower than the gemcitabine-treated group with a tumor suppression rate(TSR%) of 55.4%. Together, our results demonstrate that D(RGERPPR) is a potential tumor-penetrating peptide.
文摘Tumor penetration is important for effectively tumor targeting drug delivery.Recently,many researches are published to overcome the barriers that restrict tumor penetration and improve drug delivery efficiency.In the mini review,we first analyzed the barriers influence the tumor penetration,including tumor microenvironment barriers,nanoparticle properties,and interaction barriers between tumor and nanoparticles.To overcome the barrier,several strategies are developed,including modulating tumor microenvironment,changing particle size,transcytosis enabled tumor penetration,cell penetrating peptide modification and overcoming binding site barrier,which could effectively improve tumor penetration,and finally enhance tumor treatment outcome.
文摘Drug resistance renders standard chemotherapy ineffective in the treatment of connective tissue growth factor （CTGF）-overexpressing breast cancer. By co-embedding the breast tumor cell-penetrating peptide （PEGA-pVEC） and hyaluronic acid （HA） as a targeting media, novel cascaded targeting nanoparficles （HACT NPs） were created on a rattle mesoporous silica （rmSiO2） scaffold for the pinpoint delivery of siRNAs along with an anticancer drug, aiming at overcoming the drug resistance of CTGF-overexpressing breast cancer in vivo. The targeting nanoparticles selectively accumulated in the vasculature under the guidance of the PEGA-pVEC peptide, cascaded by receptor-mediated endocytosis with the aid of another targeting agent, HA, presenting a greater in vivo tumor targeting ability than single targeting ligand vectors. In addition, an HA shell prevented the leakage of therapeutic drugs during the cargo transport process, until the hyaluronidase （HAase）-triggered degradation upon lysosomes entering, guaranteeing a controllable drug release inside the target cells. When the protective shell disintegrates, the released siRNA took charge to silence the gene associated with drug resistance, CTGF, thus facilitating doxorubicin-induced apoptosis. The cascaded targeting media （PEGA-pVEC and HA） advances precision-guided therapy in vivo, while the encapsulation of siRNAs into a chemotherapy drug delivery system provides an efficient strategy for the treatment of drug resistance cancers.
