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1.
In this study, a type of biocompatible and biodegradable oil-in-water emulsion for hydrophobic drug delivery was evaluated in vitro and in vivo. Bovine serum albumin (BSA)-dextran conjugates with different dextran molecular weights and different conjugation degrees were used as the emulsifier and stabilizer. Paclitaxel (PTX), a hydrophobic antitumor drug, was effectively loaded inside the oil droplets via high-pressure homogenization. The emulsions were heated at 90° C for 1 h to eliminate the anaphylaxis of BSA. By virtue of the cross-linked BSA films at the oil–water interfaces produced by the heat treatment and the hydrophilic dextran surfaces, the emulsions are stable in blood serum, as well as stable against long-term storage. In vitro cytotoxicity study verifies that the unloaded emulsions are biocompatible and the PTX-loaded emulsions have similar antitumor activity as PTX solution. In vivo investigation of murine ascites hepatoma H22-tumor-bearing mice demonstrates that the PTX-loaded emulsion with shorter and denser dextran surface has better tumor inhibition and survivability efficacy than the commercial PTX injection.  相似文献   

2.
In this study, to develop a multifunctional targeting nano-carrier drug delivery system for cancer therapy, the novel pH-sensitive ketal based oligosaccharides of hyaluronan (oHA) conjugates were synthesized by chemical conjugation of hydrophobic menthone 1,2-glycerol ketal (MGK) to the backbone of oHA with the histidine as the linker of proton sponge effect. The multifunctional oHA conjugates, oHA-histidine-MGK (oHM) carried the pH-sensitive MGK as hydrophobic moieties and oHA as the target of CD44 receptor. The oHM could self-assemble to nano-sized spherical shape with the average diameters of 128.6?nm at pH 7.4 PBS conditions. The oHM nanoparticles (oHMN) could release encapsulated curcumin (Cur) with 82.6% at pH 5.0 compared with 49.3% at pH 7.4. The results of cytotoxicity assay indicated that encapsulated Cur in oHMN (Cur-oHMN) were stable and have less toxicity compared to Cur suspension. The anti-tumor efficacy in vivo suggested that Cur-oHMN suppressed tumor growth most efficiently. These results present the promising potential of oHMN as a stable and effective nano-sized pH-sensitive drug delivery system for cancer treatment.  相似文献   

3.
The poor selectivity of chemotherapeutics for cancer treatment may lead to dose-limiting side effects that compromise clinical outcomes. To solve the problem, surface-functionalized polymer nanoparticles are regarded as promising tumor-targeting delivery system. On the basis of glucose transporter (GLUT) overexpression on cancer cells, d-glucosamine-conjugated and paclitaxel-loaded poly(ethylene glycol)-co-poly(trimethylene carbonate) copolymer nanoparticles (DGlu-NP/PTX) were developed as potential tumor-targeting drug delivery system in this study. Because of the high affinity between d-glucosamine and GLUT, DGlu-NP/PTX could target to tumor tissue through GLUT-mediated endocytosis to improve the selectivity of PTX. DGlu-NP/PTX was prepared by emulsion/solvent evaporation technique and characterized in terms of morphology, size, and zeta potential. In vitro evaluation of two-dimensional cells and three-dimensional tumor spheroids revealed that DGlu-NP/PTX was more potent than those of plain nanoparticles (NP/PTX) and Taxol. In vivo multispectral fluorescent imaging indicated that DGlu-NP had higher specificity and efficiency on subcutaneous xenografts tumor of mouse. Furthermore, DGlu-NP/PTX showed the greatest tumor growth inhibitory effect on in vivo subcutaneous xenografts model with no evident toxicity. Therefore, these results demonstrated that DGlu-NP/PTX could be used as potential vehicle for cancer treatment. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.  相似文献   

4.
Exosomes have emerged as a promising drug carrier with low immunogenicity, high biocompatibility and delivery efficiency. Here in, we isolated exosomes from A33-positive LIM1215 cells (A33-Exo) and loaded them with doxorubicin (Dox). Furthermore, we coated surface-carboxyl superparamagnetic iron oxide nanoparticles (US) with A33 antibodies (A33Ab-US), expecting that these A33 antibodies on the surface of the nanoparticles could bind to A33-positive exosomes and form a complex (A33Ab-US-Exo/Dox) to target A33-positive colon cancer cells. The results showed that A33Ab-US-Exo/Dox had good binding affinity and antiproliferative effect in LIM1215 cells, as shown by increased uptake of the complex. In vivo study showed that A33Ab-US-Exo/Dox had an excellent tumor targeting ability, and was able to inhibit tumor growth and prolong the survival of the mice with reduced cardiotoxicity. In summary, exosomes functionalized by targeting ligands through coating with high-density antibodies may prove to be a novel delivery system for targeted drugs against human cancers.  相似文献   

5.
《药学学报(英文版)》2020,10(8):1549-1562
Although high-efficiency targeted delivery is investigated for years, the efficiency of tumor targeting seems still a hard core to smash. To overcome this problem, we design a three-step delivery strategy based on streptavidin–biotin interaction with the help of c(RGDfK), magnetic fields and lasers. The ultrasmall superparamagnetic iron oxide nanoparticles (USIONPs) modified with c(RGDfK) and biotin are delivered at step 1, followed by streptavidin and the doxorubicin (Dox) loaded nanosystems conjugated with biotin at steps 2 and 3, respectively. The delivery systems were proved to be efficient on A549 cells. The co-localization of signal for each step revealed the targeting mechanism. The external magnetic field could further amplify the endocytosis of USPIONs based on c(RGDfK), and magnify the uptake distinctions among different test groups. Based on photoacoustic imaging, laser-heating treatment could enhance the permeability of tumor venous blood vessels and change the insufficient blood flow in cancer. Then, it was noticed in vivo that only three-step delivery with laser-heating and magnetic fields realized the highest tumor distribution of nanosystem. Finally, the magnetism/laser-auxiliary cascaded delivery exhibited the best antitumor efficacy. Generally, this study demonstrated the necessity of combining physical, biological and chemical means of targeting.  相似文献   

6.
Context: Paclitaxel (PTX) and carboplatin (CBP) are widely used for the combined chemotherapy of non-small cell lung cancer (NSCLC). However, the development of multidrug resistance of cancer cells, as well as systemic toxic side effects resulting from nonspecific localization of anticancer drugs to non-tumor areas are major obstacles to the success of chemotherapy in treating cancers.

Objective: This study aimed to engineer a prodrug-based nano-drug delivery system for co-encapsulate hydrophilic (CBP) and hydrophobic anti-tumor drugs (PTX). This system was expected to resolve the multidrug resistance cause by single drug, and the dual-drug-loaded liposome was also planned to specifically target the cancer cells without obvious influence on normal cells and tissues.

Methods: In this paper, PLGA-PEG-CBP was synthesized by the conjugation between the carboxylic group of PLGA-PEG-COOH and the amino group of CBP. Then, self-assembled nanoparticles for combination delivery of PTX and PLGA-PEG-CBP (PTX/CBP NPs) were prepared by solvent displacement technique. The in vitro and in vivo anti-tumor efficacy was assessed in NCL-H460 human non-small cell lung carcinoma cell line.

Results: PTX/CBP NPs achieved the highest cytotoxic effect among all formulations in vitro, as compared with single drug delivery NPs. In vivo investigation on NSCLC animal models showed that co-delivery of PTX and CBP possessed high tumor-targeting capacity and strong anti-tumor activity.

Conclusions: The PTX/CBP NPs constructed in this research offers an effective strategy for targeted combinational lung cancer therapy.  相似文献   

7.
It can be found from a large number of cancer treatments that use of anti-cancer drugs alone often presents low efficacy and high side effects. This study aims to develop a new drug carrier with tumor-specific response, controlled release in vivo and high tumor-suppressive property. Inorganic nano-materials MnO2 with pH and glutathione (GSH, abundant in cancer cells) responsiveness were used to construct sustained-release functional nano-liposome to be an excellent in vivo pH-sensitive drug delivery system. Some hydrophilic MnO2, gefitinib (Geb), and bevacizumab (Beb) were encapsulated in the phospholipid vesicles (liposomes), so as to integrate several anti-tumor drugs (MnO2-PDA@Lipo@Geb@Beb) to achieve effective treatment of non-small cell lung cancer (NSCLC). Part of the MnO2 nanorods on the lipid shell had the properties of pH and GSH responsiveness, which could further enhance anti-cancer efficacy. Cell assay results showed that MnO2-PDA@Lipo@Geb@Beb nano-drug had an effective inhibition on A549 cell progression and showed excellent biocompatibility. In vivo results further confirmed that MnO2-PDA@Lipo@Geb@Beb nano-drug could effectively inhibit the growth of NSCLC cells. Overall, it can be inferred from the above experimental results that the nanocomposite drug is expected to be widely used in the clinical application of lung cancer.  相似文献   

8.
Paclitaxel (PTX) is a microtubule inhibitor administered as an albumin-bound nanoformulation for the treatment of breast cancer. However, the effectiveness of PTX is limited by resistance mechanisms mediated in part by upregulation of the anti-apoptotic BCL-2 and P-glycoprotein (P-gp). Present investigation was designed to study the synergistic potential of NuBCP-9 and PTX loaded polymeric nanoparticles to minimize the dose and improve the efficacy and safety. PTX and NuBCP-9 loaded polylactic acid–polyethylene glycol-polypropylene glycol-polyethylene glycol [PLA-(PEG-PPG-PEG)] nanoparticles were prepared by double emulsion solvent evaporation method. PTX and NuBCP-9 loaded NPs displayed an average size of 90?nm with spherical morphology. PTX and NuBCP-9 dual loaded NPs reducedIC50 by ~40-fold and acted synergistically. Treatment of the syngeneic EAT mice with PTX-NuBCP-9/NPs resulted in improved efficacy than that alone treated mice. Overall, the concomitant delivery PTX and NuBCP-9 loaded NPs showed superior activity than that of PTX and NuBCP-9 alone treated mice.  相似文献   

9.
The extremely low bioavailability of oral paclitaxel(PTX) mainly due to the complicated gastrointestinal environment,the obstruction of intestinal mucus layer and epithelium barrier.Thus,it is of great significance to construct a coordinative delivery system which can overcome multiple intestinal physicochemical obstacles simultaneously.In this work,a high-density PEGylation-based glycocholic acid-decorated micelles(PTX@GNPs) was constructed by a novel polymer,9-Fluorenylmethoxy carbonyl-poly et...  相似文献   

10.
Breast cancer remains one of the most common cancers for females. Drug delivery based on cancer nanotechnology could improve the performance of some chemotherapeutic medicines already used in clinic. The emergence of polymersomes provided the potential to encapsulate hydrophobic/hydrophilic drugs. By modifying the weight ratio of methoxy-poly (ethylene glycol) (mPEG) chain to ethyl-p-aminobenzoate (EAB) side group, a series of amphiphilic graft polyphosphazenes (PEPs) was prepared. PEP can be tuned from micelles to polymersomes with the decrease of mPEG content via dialysis. Either hydrophilic doxorubicin hydrochloride (DOX·HCl) or hydrophobic doxorubicin base (DOX) could be encapsulated into PEP polymersomes with high payload and high encapsulation efficiency due to the strong intermolecular interaction with PEP. Compared with free DOX·HCl administration, in vivo investigation in growth inhibition of MCF-7 xenograft tumors in nude mice demonstrated that PEP polymersomes could enhance life safety without compromise of therapeutic efficacy, especially DOX·HCl loaded delivery system.From the Clinical EditorIn this preclinical study, polymerosomes based on PEPs were investigated as doxorubicin delivery systems, demonstrating similar efficacy but less toxicity compared to standard delivery methods.  相似文献   

11.
《药学学报(英文版)》2022,12(10):3972-3985
Due to the overwhelming percentage of poorly water-soluble drugs, pharmaceutical industry is in urgent need of efficient approaches for solubilization and permeability improvement. Salts consisting of lipophilic fatty acid anions and hydrophilic choline cations are found to be surface active and able to form ionic co-aggregates (ICAs) in water. Choline oleate-based ICAs significantly enhance oral absorption of paclitaxel (PTX) as compared with cremophor EL-based micelles (MCs). Aggregation-caused quenching probes enable tracking of intact ICAs in in vivo transport and cellular interaction. Prolonged intestinal retention of ICAs than MCs implies stronger solubilizing capability in vivo. Ex vivo imaging of major organs and intestinal tracts suggests transepithelial transport of intact ICAs. Cellular studies support the enhanced absorption of PTX and transmembrane transport of intact ICAs. In conclusion, ICAs, consisting of lipophilic ions and hydrophilic counter-ions, are of great potential in delivery of poorly water-soluble drugs by enhancing solubility and permeability.  相似文献   

12.
Doxorubicin-encapsulating liposomal formulations, known as Doxil, have been used for the treatment of Kaposi’s sarcoma and ovarian cancer. However, there is still a need for a drug delivery system for doxorubicin that limits the treatment’s side effects, namely, mucositis and hand-and-foot syndrome. The AG73 peptide derived from the laminin α1 chain is a ligand for syndecans, and syndecan-2 is highly expressed in some cancer cells. In this study, to develop a safer and more selective liposomal formulation, we prepared doxorubicin-encapsulating AG73 peptide-modified liposomes (AG73–Dox). First, we assessed the selectivity of AG73–Dox for cancer cells, including syndecan-2 over-expressing cells, using flow cytometry and confocal microscopy. AG73–Dox showed selective cellular uptake on cancer cells and enhancement of the intracellular uptake. Next, we examined the cytotoxicity of AG73–Dox using a WST assay. AG73–Dox exhibited a higher cytotoxicity against cancer cells than other control liposomes. In addition, we showed that the antitumor efficacy of AG73–Dox in vivo was better than that of free Dox. When we examined the biodistribution of liposomes, AG73 peptide-modified liposomes (AG73-L) tended to bind to intratumoral vessels and extravasated in the tumor tissue. Thus, further optimization of AG73-L toward tumor targeting may lead to a development of a useful tool for cancer therapy.  相似文献   

13.
The drug delivery systems improve the efficacy of chemotherapeutics through enhanced targeting and controlled release however, biological barriers of tumor microenvironment greatly impede the penetration of nanomedicine within the tumor. We report herein the fabrication of a PEG-detachable silybin (SLB) pH-sensitive liposome decorated with TAT-peptide. For this, Acyl hydrazide-activated PEG2000 was prepared and linked with ketone-derivatized DPPE via an acid-labile hydrazone bond to form mPEG2000-HZ-DPPE. TAT peptide was conjugated with a shorter -PEG1000-DSPE spacer and post-inserted into PEGylated liposome (DPPC: mPEG2000–DSPE: Chol). To prepare nanoliposomes (around 100 nm), first, a novel method was used to prepare SLB-Soya PC (SLB-SPC) complex, then this complex was incorporated into nanoliposomes. The pH-sensitivity and shielding effect of long PEG chain on TAT peptide was investigated using DiI liposome and FACS analysis. Pre-treatment to the lowered pH enhanced cellular association of TAT-modified pH-sensitive liposome due to the cleavage of hydrazone bond and TAT exposure. Besides, TAT-modified pH-sensitive liposomes significantly reduced cell viability compared to the plain liposome. In vivo results were very promising with pH-sensitive liposome by detaching PEG moieties upon exposure to the acidic tumor microenvironment, enhancing cellular uptake, retarding tumor growth, and prolonging the survival of 4T1 breast tumor-bearing BALB/c mice. TAT modification of pH-sensitive liposome improved cancer cell association and cytotoxicity and demonstrated potential intracellular delivery upon exposure to acidic pH. However, in in vivo studies, TAT as a targeting ligand significantly decreased the therapeutic efficacy of the formulation attributed to an inefficient tumor accumulation and higher release rate in the circulation. The results of this study indicated that pH-sensitive liposome containing SLB, which was prepared with a novel method with a significant SLB loading efficiency, is very effective in the treatment of 4T1 breast tumor-bearing BALB/c mice and merits further investigation.  相似文献   

14.
This study describes a novel nanocarrier of emulsion liposomes (eLiposomes) composed of a perfluoropentane nanodroplet within the aqueous interior of a DPPC liposome, along with the anticancer drug doxorubicin (Dox). The eLiposome containing Dox (eLipoDox) displayed good release of Dox upon insonation with low intensity ultrasound at 20-kHz, 1.0-MHz and 3.0-MHz. More release occurs in vitro at 20-kHz than at the higher frequencies. Controlled delivery was demonstrated by applying ultrasound (US) to HeLa tumor cells in vitro. The confocal images of Dox release to cells indicate that eLipoDox is an effective carrier of chemotherapeutic agent, and releases Dox to the cell cytosol upon insonation. This novel drug delivery system promises to provide more effective US therapy and tumor treatment and has the potential to reduce the side effects of cardiotoxicity caused by Dox.From the Clinical EditorIn this paper, an ultrasound-sensitive doxorubicine-carrying nanoliposome delivery system is reported. Doxorubicin release as a result of ultrasound exposure is clearly demonstrated, paving the way to potential clinical applications with the aim of reducing the systemic toxicity and enhanced local delivery of this compound.  相似文献   

15.
Multidrug resistance (MDR) has been considered as a huge challenge to the effective chemotherapy. Therefore, it is necessary to develop new strategies to effectively overcome MDR. Here, based on the previous research of N-(2-hydroxypropyl)methacrylamide (HPMA) polymer–drug conjugates, we designed an effective system that combined drug-efflux circumvention and mitochondria targeting of anticancer drug doxorubicin (Dox). Briefly, Dox was modified with mitochondrial membrane penetrating peptide (MPP) and then attached to (HPMA) copolymers (P-M-Dox). Our study showed that macromolecular HPMA copolymers successfully bypassed drug efflux pumps and escorted Dox into resistant MCF-7/ADR cells via endocytic pathway. Subsequently, the mitochondria accumulation of drugs was significantly enhanced with 11.6-fold increase by MPP modification. The excellent mitochondria targeting then resulted in significant enhancement of reactive oxygen species (ROS) as well as reduction of adenosine triphosphate (ATP) production, which could further inhibit drug efflux and resistant cancer cell growth. By reversing Dox resistance, P-M-Dox achieved much better suppression in the growth of 3D MCF-7/ADR tumor spheroids compared with free Dox. Hence, our study provides a promising approach to treat drug-resistant cancer through simultaneous drug efflux circumvention and direct mitochondria delivery.  相似文献   

16.
A doxorubicin (Dox) and curcumin (Cur) combination treatment regimen has been widely studied in pre-clinical research. However, the nanoparticles developed for this combination therapy require a consecutive drug loading process because of the different water-solubility of these drugs. This study provides a strategy for the “one-step” formation of nanoparticles encapsulating both Dox and Cur. We took advantage of polyacrylic acid (PAA) and calcium carbonate (CaCO3) to realise a high drug entrapment efficiency (EE) and pH-sensitive drug release using a simplified preparation method. Optimisation of lipid ratios and concentrations of CaCO3 was conducted. Under optimal conditions, the mean diameter of PEGylated lipid/PAA/CaCO3 nanoparticles with encapsulated Cur and Dox (LPCCD) was less than 100?nm. An obvious pH-sensitive release of both drugs was observed, with different Dox and Cur release rates. Successful co-delivery of Cur and Dox was achieved via LPCCD on HepG2 cells. LPCCD altered the bio-distribution of Dox and Cur in vivo and decreased Dox-induced cardiotoxicity. The current investigation has developed an efficient ternary system for co-delivery of Dox and Cur to tumours, using a “one-step” formation resulting in nanoparticles possessing remarkable pH-sensitive drug release behaviour, which may be valuable for further clinical studies and eventual clinical application.  相似文献   

17.
Poly-l-lysine (PLL) dendrimers are currently being investigated as antiangiogenic agent for therapy of cancer. In this study, we report folate conjugated poly-l-lysine dendrimers (FPLL) as an efficient carrier for model anticancer drug, doxorubicin hydrochloride (Dox); for pH sensitive drug release, selective targeting to cancer cells, anticancer activity and antiangiogenic activity. This nanoconjugate of Dox showed initial rapid in vitro release followed by gradual slow release, and the drug release was found to be pH sensitive with greater release at acidic pH. In the CAM assay and tubule formation assay with HUVEC, Dox-FPLL formulation showed the significant antiangiogenic activity confirming that activity of PLL was not compromised by the presence of Dox and folic acid. The ex vivo investigations with human breast cancer cell lines MCF-7 showed enhanced cytotoxicity of Dox-FPLL with significantly enhanced intracellular uptake (p < 0.001). The in vivo therapeutic potential of nanoconjugate was determined in MCF-7 breast cancer xenograft model in tumor-bearing mice. Dox-FPLL increased the concentration of Dox in tumor by 121.5-fold after 24 h in comparison with free Dox formulation. The folate conjugated dendrimeric Dox showed superior anti-tumor activity in tumor xenograft model with significantly prolonged survival determined by Kaplan Meier survival analysis (p < 0.001).  相似文献   

18.
The development of multidrug resistance (MDR) is a major hindrance to cancer eradication as it renders tumors unresponsive to most chemotherapeutic treatments and is associated with cancer resurgence. This study describes a novel mechanism to overcome MDR through a polymer-blend nanoparticle platform that delivers a combination therapy of C6-ceramide (CER), a synthetic analog of an endogenously occurring apoptotic modulator, together with the chemotherapeutic drug paclitaxel (PTX), in a single formulation. The PTX/CER combination therapy circumvents another cellular mechanism whereby MDR develops, by lowering the threshold for apoptotic signaling. In vivo studies in a resistant subcutaneous SKOV3 human ovarian and in an orthotopic MCF7 human breast adenocarcinoma xenograft showed that the PTX and CER nanoparticle combination therapy reduced the final tumor volume at least twofold over treatment with the standard PTX therapy alone. The study also revealed that the cotherapy accomplished this enhanced efficacy by generating an enhancement in apoptotic signaling in both tumor types. Additionally, acute evaluation of safety with the combination therapy did not show significant changes in body weight, white blood cell counts, or liver enzyme levels. The temporal-controlled nanoparticle delivery system presented in this study allows for a simultaneous delivery of PTX + CER in breast and ovarian tumor model drug, leading to a modulation of the apoptotic threshold. This strategy has tremendous potential for effective treatment of refractory disease in cancer patients.  相似文献   

19.
The application of paclitaxel (PTX) in clinic has been restricted due to its poor solubility. Several traditional nano-medicines have been developed to improve this defect, while they are still lack of tumor targeting ability and rapid drug release. In this work, an amphiphilic polymeric micelle of hyaluronic acid (HA) – all-trans-retinoid acid (ATRA) with a disulfide bond, was developed successfully for the co-delivery of PTX and ATRA. The combination chemotherapy of PTX and ATRA can strengthen the anti-tumor activity. Along with self-assembling to micelles in water, the delivery system displayed satisfying drug loading capacities for both PTX (32.62% ± 1.39%) and ATRA, due to directly using ATRA as the hydrophobic group. Rapid drug release properties of the PTX-loaded redox-sensitive micelles (HA-SS-ATRA) in vitro were confirmed under reducing condition containing GSH. Besides, HA-CD44 mediated endocytosis promoted the uptake of HA-SS-ATRA micelles by B16F10 cells. Due to these properties, cytotoxicity assay verified that PTX-loaded HA-SS-ATRA micelles showed concentration-dependent cytotoxicity and displayed obvious combination therapy of PTX and ATRA. Importantly, HA-SS-ATRA micelles could remarkably prolong plasma circulation time after intravenously administration. Therefore, redox-sensitive HA-SS-ATRA micelles could be utilized and explored as a promising drug delivery system for cancer combination chemotherapy.  相似文献   

20.
Tumor-associated macrophages (TAMs) and angiogenesis are increasingly considered as the pivotal factors that affect tumor progress. Herein, we developed the paclitaxel (PTX)-loaded nanoparticles (NP/PTX) and decorated it with an innovative peptide YI (YINP/PTX) for simultaneously targeting delivery of drug to TAMs and angiogenesis. We demonstrated that the modification of YI peptide significantly enhanced the internalization of nanoparticles by cells and accumulation of nanoparticles in tumor tissues, but down regulated the distribution of them in normal tissues especially the liver. We also made a confirmation that the YI peptide decorated nanoparticles had an excellent co-localization with TAMs and angiogenesis in vivo. Finally, in the HT-26 colorectal tumor-bearing mice, a pharmacodynamic evaluation was performed and results showed that the YINP/PTX was more effective than other PTX formulations in anti-tumor growth. These results together suggested that the prepared nanoparticles are promising in targeting delivery of chemotherapeutics to tumor microenvironment for enhancing tumor therapy effect.  相似文献   

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