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1.
Molecular therapy using a small interfering RNA (siRNA) has shown promise in the development of novel therapeutics. Various formulations have been used for in vivo delivery of siRNAs. However, the stability of short double‐stranded RNA molecules in the blood and efficiency of siRNA delivery into target organs or tissues following systemic administration have been the major issues that limit applications of siRNA in human patients. In this study, multifunctional siRNA delivery nanoparticles are developed that combine imaging capability of nanoparticles with urokinase plasminogen activator receptor‐targeted delivery of siRNA expressing DNA nanocassettes. This theranostic nanoparticle platform consists of a nanoparticle conjugated with targeting ligands and double‐stranded DNA nanocassettes containing a U6 promoter and a shRNA gene for in vivo siRNA expression. Targeted delivery and gene silencing efficiency of firefly luciferase siRNA nanogenerators are demonstrated in tumor cells and in animal tumor models. Delivery of survivin siRNA expressing nanocassettes into tumor cells induces apoptotic cell death and sensitizes cells to chemotherapy drugs. The ability of expression of siRNAs from multiple nanocassettes conjugated to a single nanoparticle following receptor‐mediated internalization should enhance the therapeutic effect of the siRNA‐mediated cancer therapy.  相似文献   

2.
Lipopolymer 49, a solid‐phase synthesized T‐shaped peptide‐like oligoamide containing two central oleic acids, 20 aminoethane, and two terminal cysteine units, is identified as very potent and biocompatible small interfering RNA (siRNA) carrier for gene silencing in glioma cells. This carrier is combined with a novel targeting polymer 727, containing a precise sequence of Angiopep 2 targeting peptide, linked with 28 monomer units of ethylene glycol, 40 aminoethane, and two terminal cysteines in siRNA complex formation. Angiopep‐polyethylene glycol (PEG)/siRNA polyplexes exhibit good nanoparticle features, effective glioma‐targeting siRNA delivery, and intracellular siRNA release, resulting in an outstanding gene downregulation both in glioma cells and upon intravenous delivery in glioma model nude mice without significant biotoxicity. Therefore, this novel siRNA delivery system is expected to be a promising strategy for targeted and safe glioma therapy.  相似文献   

3.
Nucleic acid‐based therapies rely on efficient formulations for nucleic acid protection and delivery. As nonviral strategies, polymeric and lipid‐based nanoparticles have been introduced; however, biological efficacy and biocompatibility as well as poor storage properties due to colloidal instability and their unavailability as ready‐to‐use systems are still major issues. Polyethylenimine is the most widely explored and promising candidate for gene delivery. Polyethylenimine‐based polyplexes and their combination with liposomes, lipopolyplexes, are efficient for DNA or siRNA delivery in vitro and in vivo. In this study, a highly potent spray‐dried nanoparticle‐in‐microparticle delivery system is presented for the encapsulation of polyethylenimine‐based polyplexes and lipopolyplexes into poly(vinyl alcohol) microparticles, without requiring additional stabilizing agents. This easy‐to‐handle gene delivery device allows prolonged nanoparticle storage and protection at ambient temperature. Biological analyses reveal further advantages regarding profoundly reduced cytotoxicity and enhanced transfection efficacies of polyethylenimine‐based nanoparticles from the nanoparticle‐in‐microparticle delivery system over their freshly prepared counterparts, as determined in various cell lines. Importantly, this nanoparticle‐in‐microparticle delivery system is demonstrated as ready‐to‐use dry powder to be an efficient device for the inhalative delivery of polyethylenimine‐based lipopolyplexes in vivo, as shown by transgene expression in mice after only one administration.  相似文献   

4.
Hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide. Small interfering RNA (siRNA) holds promise as a new class of therapeutics for HCC, as it can achieve sequence‐specific gene knockdown with low cytotoxicity. However, the main challenge in the clinical application of siRNA lies in the lack of effective delivery approaches that need to be highly specific and thus incur low or no systemic toxicity. Here, a nonviral nanoparticle‐based gene carrier is presented that can specifically deliver siRNA to HCC. The nanovector (NP‐siRNA‐GPC3 Ab) is made of an iron oxide core coated with chitosan‐polyethylene glycol (PEG) grafted polyethyleneimine copolymer, which is further functionalized with siRNA and conjugated with a monoclonal antibody (Ab) against human glypican‐3 (GPC3) receptor highly expressed in HCC. A rat RH7777 HCC cell line that coexpresses human GPC3 and firefly luciferase (Luc) is established to evaluate the nanovector. The nanoparticle‐mediated delivery of siRNA against Luc effectively suppresses Luc expression in vitro without notable cytotoxicity. Significantly, NP‐siLuc‐GPC3 Ab administered intravenously in an orthotopic model of HCC is able to specifically bound to tumor and induce remarkable inhibition of Luc expression. The findings demonstrate the potential of using this nanovector for targeted delivery of therapeutic siRNA to HCC.  相似文献   

5.
A novel light‐operated vehicle for targeted intracellular drug delivery is constructed using photosensitizer‐incorporated G‐quadruplex DNA‐capped mesoporous silica nanoparticles. Upon light irradiation, the photosensitizer generates ROS, causing the DNA capping to be cleaved and allowing cargo to be released. Importantly, this platform makes it possible to develop a drug‐carrier system for the synergistic combination of chemotherapy and PDT for cancer treatment with spatial/temporal control. Furthermore, the introducing of targeting ligands further improves tumor targeting efficiency. The excellent biocompatibility, cell‐specific intracellular drug delivery, and cellular uptake properties set up the basis for future biomedical application that require in vivo controlled, targeted drug delivery.  相似文献   

6.
Targeted delivery of intracellularly active diagnostics and therapeutics in vivo is a major challenge in cancer nanomedicine. A nanocarrier should possess long circulation time yet be small and stable enough to freely navigate through interstitial space to deliver its cargo to targeted cells. Herein, it is shown that by adding targeting ligands to nanoparticles that mimic high‐density lipoprotein (HDL), tumor‐targeted sub‐30‐nm peptide–lipid nanocarriers are created with controllable size, cargo loading, and shielding properties. The size of the nanocarrier is tunable between 10 and 30 nm, which correlates with a payload of 15–100 molecules of fluorescent dye. Ligand‐directed nanocarriers targeting epidermal growth factor receptor (EGFR) are confirmed both in vitro and in vivo. The nanocarriers show favorable circulation time, tumor accumulation, and biodistribution with or without the targeting ligand. The EGFR targeting ligand is proved to be essential for the EGFR‐mediated tumor cell uptake of the nanocarriers, a prerequisite of intracellular delivery. The results demonstrate that targeted HDL‐mimetic nanocarriers are useful delivery vehicles that could open new avenues for the development of clinically viable targeted nanomedicine.  相似文献   

7.
The abilities to deliver siRNA to its intended action site and assess the delivery efficiency are challenges for current RNAi therapy, where effective siRNA delivery will join force with patient genetic profiling to achieve optimal treatment outcome. Imaging could become a critical enabler to maximize RNAi efficacy in the context of tracking siRNA delivery, rational dosimetry and treatment planning. Several imaging modalities have been used to visualize nanoparticle‐based siRNA delivery but rarely did they guide treatment planning. We report a multimodal theranostic lipid‐nanoparticle, HPPS(NIR)‐chol‐siRNA, which has a near‐infrared (NIR) fluorescent core, enveloped by phospholipid monolayer, intercalated with siRNA payloads, and constrained by apoA‐I mimetic peptides to give ultra‐small particle size (<30 nm). Using fluorescence imaging, we demonstrated its cytosolic delivery capability for both NIR‐core and dye‐labeled siRNAs and its structural integrity in mice through intravenous administration, validating the usefulness of NIR‐core as imaging surrogate for non‐labeled therapeutic siRNAs. Next, we validated the targeting specificity of HPPS(NIR)‐chol‐siRNA to orthotopic tumor using sequential four‐steps (in vivo, in situ, ex vivo and frozen‐tissue) fluorescence imaging. The image co‐registration of computed tomography and fluorescence molecular tomography enabled non‐invasive assessment and treatment planning of siRNA delivery into the orthotopic tumor, achieving efficacious RNAi therapy.  相似文献   

8.
The paradigm of using nanoparticle‐based formulations for drug delivery relies on their enhanced passive accumulation in the tumor interstitium. Nanoparticles with active targeting capabilities attempt to further enhance specific delivery of drugs to the tumors via interaction with overexpressed cellular receptors. Consequently, it is widely accepted that drug delivery using actively targeted nanoparticles maximizes the therapeutic benefit and minimizes the off‐target effects. However, the process of nanoparticle mediated active targeting initially relies on their passive accumulation in tumors. In this article, it is demonstrated that these two tumor‐targeted drug delivery mechanisms are interrelated and dosage dependent. It is reported that at lower doses, actively targeted nanoparticles have distinctly higher efficacy in tumor inhibition than their passively targeted counterparts. However, the enhanced permeability and retention effect of the tumor tissue becomes the dominant factor influencing the efficacy of both passively and actively targeted nanoparticles when they are administered at higher doses. Importantly, it is demonstrated that dosage is a pivotal parameter that needs to be taken into account in the assessment of nanoparticle mediated targeted drug delivery.  相似文献   

9.
Co‐delivery of both chemotherapy drugs and siRNA from a single delivery vehicle can have a significant impact on cancer therapy due to the potential for overcoming issues such as drug resistance. However, the inherent chemical differences between charged nucleic acids and hydrophobic drugs have hindered entrapment of both components within a single carrier. While poly(ethylene glycol)‐block‐poly(lactic‐co‐glycolic acid) (PEG–PLGA) copolymers have been used successfully for targeted delivery of chemotherapy drugs, loading of DNA or RNA has been poor. It is demonstrated that significant amounts of DNA can be encapsulated within PLGA‐containing nanoparticles through the use of a new synthetic DNA analog, click nucleic acids (CNAs). First, triblock copolymers of PEG‐CNA‐PLGA are synthesized and then formulated into polymer nanoparticles from oil‐in‐water emulsions. The CNA‐containing particles show high encapsulation of DNA complementary to the CNA sequence, whereas PEG‐PLGA alone shows minimal DNA loading, and non‐complementary DNA strands do not get encapsulated within the PEG‐CNA‐PLGA nanoparticles. Furthermore, the dye pyrene can be successfully co‐loaded with DNA and lastly, a complex, larger DNA sequence that contains an overhang complementary to the CNA can also be encapsulated, demonstrating the potential utility of the CNA‐containing particles as carriers for chemotherapy agents and gene silencers.  相似文献   

10.
Despite the promise of ribonucleic acid interference therapeutics, the delivery of oligonucleotides selectively to diseased tissues in the body, and specifically to the cellular location in the tissues needed to provide optimal therapeutic outcome, remains a significant challenge. Here, key material properties and biological mechanisms for delivery of short interfering RNAs (siRNAs) to effectively silence target‐specific cells in vivo are identified. Using porous silicon nanoparticles as the siRNA host, tumor‐targeting peptides for selective tissue homing, and fusogenic lipid coatings to induce fusion with the plasma membrane, it is shown that the uptake mechanism can be engineered to be independent of common receptor‐mediated endocytosis pathways. Two examples of the potential broad clinical applicability of this concept in a mouse xenograft model of ovarian cancer peritoneal carcinomatosis are provided: silencing the Rev3l subunit of polymerase Pol ζ to impair DNA repair in combination with cisplatin; and reprogramming tumor‐associated macrophages into a proinflammatory state.  相似文献   

11.
Nanoparticles are used for delivering therapeutics into cells. However, size, shape, surface chemistry and the presentation of targeting ligands on the surface of nanoparticles can affect circulation half-life and biodistribution, cell-specific internalization, excretion, toxicity and efficacy. A variety of materials have been explored for delivering small interfering RNAs (siRNAs)--a therapeutic agent that suppresses the expression of targeted genes. However, conventional delivery nanoparticles such as liposomes and polymeric systems are heterogeneous in size, composition and surface chemistry, and this can lead to suboptimal performance, a lack of tissue specificity and potential toxicity. Here, we show that self-assembled DNA tetrahedral nanoparticles with a well-defined size can deliver siRNAs into cells and silence target genes in tumours. Monodisperse nanoparticles are prepared through the self-assembly of complementary DNA strands. Because the DNA strands are easily programmable, the size of the nanoparticles and the spatial orientation and density of cancer-targeting ligands (such as peptides and folate) on the nanoparticle surface can be controlled precisely. We show that at least three folate molecules per nanoparticle are required for optimal delivery of the siRNAs into cells and, gene silencing occurs only when the ligands are in the appropriate spatial orientation. In vivo, these nanoparticles showed a longer blood circulation time (t(1/2) ≈ 24.2 min) than the parent siRNA (t(1/2) ≈ 6 min).  相似文献   

12.
The last decade has seen remarkable advances in the development of drug delivery systems as alternative to parenteral injection‐based delivery of insulin. Neonatal Fc receptor (FcRn)‐mediated transcytosis has been recently proposed as a strategy to increase the transport of drugs across the intestinal epithelium. FcRn‐targeted nanoparticles (NPs) could hijack the FcRn transcytotic pathway and cross the epithelial cell layer. In this study, a novel nanoparticulate system for insulin delivery based on porous silicon NPs is proposed. After surface conjugation with albumin and loading with insulin, the NPs are encapsulated into a pH‐responsive polymeric particle by nanoprecipitation. The developed NP formulation shows controlled size and homogeneous size distribution. Transmission electron microscopy (TEM) images show successful encapsulation of the NPs into pH‐sensitive polymeric particles. No insulin release is detected at acidic conditions, but a controlled release profile is observed at intestinal pH. Toxicity studies show high compatibility of the NPs with intestinal cells. In vitro insulin permeation across the intestinal epithelium shows approximately fivefold increase when insulin is loaded into FcRn‐targeted NPs. Overall, these FcRn‐targeted NPs offer a toolbox in the development of targeted therapies for oral delivery of insulin.  相似文献   

13.
A nanoconstruct (NC) is developed from a biocompatible natural polymer and siRNA conjugates to deliver small interfering RNA (siRNA) target‐specifically without cationic condensation reagents. This study reports a novel siRNA‐mediated cross‐linked NC produced by hybridizing two complementary single‐stranded siRNAs that are conjugated to the polymer dextran via a disulfide linkage. The reducible disulfide bond between the siRNA and polymer allow siRNA release from the NC in the reducible cytoplasmic region after the NC enters the cell. In addition, when the NC contains the prostate‐carcinoma‐binding peptide aptamer DUP‐1, it can selectively deliver siRNA into prostate cancer cells of the PC‐3 lines; thus, the newly formulated NC has reduced the cytotoxicity and improved the efficacy of target‐specific siRNA delivery. Moreover, this new concept of NCs using biocompatible siRNA and a neutral polymer may provide insightful knowledge for future directions for designing NCs for stimuli‐responsive and advanced target‐specific siRNA delivery.  相似文献   

14.
An efficient and safe delivery system for small interfering RNA (siRNA) is required for clinical application of RNA interfering therapeutics. Polyethyleneimine (PEI)‐capped gold nanoparticles (AuNPs) are successfully manufactured using PEI as the reductant and stabilizer, which bind siRNA at an appropriate weight ratio by electrostatic interaction and result in well‐dispersed nanoparticles with uniform structure and narrow size distribution. With siRNA binding, PEI‐capped AuNPs induce more significant and enhanced reduction in targeted green fluorescent protein expression in MDA‐MB‐435s cells, though more internalized PEI/siRNA complexes in cells are evidenced by confocal laser scanning microscopy observation and fluorescence‐activated cell sorting analyses. PEI‐capped AuNPs/siRNA targeting endogenous cell‐cycle kinase, an oncogene polo‐like kinase 1 (PLK1), display significant gene expression knockdown and induce enhanced cell apoptosis, whereas it is not obvious when the cells are treated with PLK1 siRNA using PEI as the carrier. Without exhibiting cellular toxicity, PEI‐capped AuNPs appear to be suitable as a potential carrier for intracellular siRNA delivery.  相似文献   

15.
The use of modified nanoparticles in interactions with biological targets is attracting rapidly increasing attention. In this Full Paper, the application of gold nanoparticles capped with mercaptoethanesulfonate (Au‐MES NPs) as effective inhibitors of Herpes simplex virus type 1 infection based on their ability to mimic cell‐surface‐receptor heparan sulfate is described. Mechanistic studies reveal that Au‐MES NPs interfere with viral attachment, entry, and cell‐to‐cell spread, thereby preventing subsequent viral infection in a multimodal manner. The ligand multiplicity achieved with carrier nanoparticles is crucial in generating polyvalent interactions with the virus at high specificity, strength, and efficiency. Such multivalent‐nanoparticle‐mediated inhibition is a promising approach for alternative antiviral therapy.  相似文献   

16.
The design and synthesis of a novel reduction‐sensitive, robust, and biocompatible vesicle (SSCB[6]VC) are reported, which is self‐assembled from an amphiphilic cucurbit[6]uril (CB[6]) derivative that contains disulfide bonds between hexaethylene glycol units and a CB[6] core. The remarkable features of SSCB[6]VC include: 1) facile, non‐destructive, non‐covalent, and modular surface modification using exceptionally strong host–guest chemistry; 2) high structural stability; 3) facile internalization into targeted cells by receptor‐mediated endocytosis, and 4) efficient triggered release of entrapped drugs in a reducing environment such as cytoplasm. Furthermore, a significantly increased cytotoxicity of the anticancer drug doxorubicin to cancer cells is demonstrated using doxorubicin‐loaded SSCB[6]VC, the surface of which is decorated with functional moieties such as a folate–spermidine conjugate and fluorescein isothiocyanate–spermidine conjugate as targeting ligand and fluorescence imaging probe, respectively. SSCB[6]VC with such unique features can be used as a highly versatile multifunctional platform for targeted drug delivery, which may find useful applications in cancer therapy. This novel strategy based on supramolecular chemistry and the unique properties of CB[6] can be extended to design smart multifunctional materials for biomedical applications including gene delivery.  相似文献   

17.
Although tremendous efforts have been made on targeted drug delivery systems, current therapy outcomes still suffer from low circulating time and limited targeting efficiency. The integration of cell‐mediated drug delivery and theranostic nanomedicine can potentially improve cancer management in both therapeutic and diagnostic applications. By taking advantage of innate immune cell's ability to target tumor cells, the authors develop a novel drug delivery system by using macrophages as both nanoparticle (NP) carriers and navigators to achieve cancer‐specific drug delivery. Theranostic NPs are fabricated from a unique polymer, biodegradable photoluminescent poly (lactic acid) (BPLP‐PLA), which possesses strong fluorescence, biodegradability, and cytocompatibility. In order to minimize the toxicity of cancer drugs to immune cells and other healthy cells, an anti‐BRAF V600E mutant melanoma specific drug (PLX4032) is loaded into BPLP‐PLA nanoparticles. Muramyl tripeptide is also conjugated onto the nanoparticles to improve the nanoparticle loading efficiency. The resulting nanoparticles are internalized within macrophages, which are tracked via the intrinsic fluorescence of BPLP‐PLA. Macrophages carrying nanoparticles deliver drugs to melanoma cells via cell–cell binding. Pharmacological studies also indicate that the PLX4032 loaded nanoparticles effectively kill melanoma cells. The “self‐powered” immune cell‐mediated drug delivery system demonstrates a potentially significant advancement in targeted theranostic cancer nanotechnologies.  相似文献   

18.
Nanoparticles have been investigated as drug delivery vehicles, contrast agents, and multifunctional devices for patient care. Current nanoparticle‐based therapeutic strategies for cancer treatment are mainly based on delivery of chemotherapeutic agents to induce apoptosis or DNA/siRNA to regulate oncogene expression. Here, a nanoparticle system that demonstrates an alternative approach to the treatment of cancers through the inhibition of cell invasion, while serving as a magnetic resonance and optical imaging contrast agent, is presented. The nanoparticle comprises an iron oxide nanoparticle core conjugated with an amine‐functionalized poly(ethylene glycol) silane and a small peptide, chlorotoxin (CTX), which enables the tumor cell‐specific binding of the nanoparticle. It is shown that the nanoparticle exhibits substantially enhanced cellular uptake and an invasion inhibition rate of ~98% compared to unbound CTX (~45%). Significantly, the investigation from flow cytometry analysis, transmission electron microscopy, and fluorescent imaging reveals that the CTX‐enabled nanoparticles deactivated the membrane‐bound matrix metalloproteinase 2 (MMP‐2) and induced increased internalization of lipid rafts that contain surface‐expressed MMP‐2 and volume‐regulating ion channels through receptor‐mediated endocytosis, leading to enhanced prohibitory effects. Since upregulation and activity of MMP‐2 have been observed in tumors of neuroectodermal origin, and in cancers of the breast, colon, skin, lung, prostate, ovaries, and a host of others, this nanoparticle system can be potentially used for non‐invasive diagnosis and treatment of a variety of cancer types.  相似文献   

19.
The chemotherapy of glioblastoma is severely hindered by the immunosuppressive tumor microenvironment, especially the tumor growth factor β (TGF‐β), an immunosuppressive cytokine. In this study, it is proposed to employ RNAi‐based immunomodulation to modify the tumor immune microenvironment and improve the effect of chemotherapy. Herein, a nanotheranostic system (Angiopep LipoPCB(Temozolomide+BAP/siTGF‐β), ALBTA) with dual targeting and ROS response is established for intracranial glioblastoma treatment. The traceable nanoparticles exhibit strong siRNA condensation, high drug loading efficiency, good serum stability, and magnetic property. They can efficiently cross the blood–brain barrier and target to glioblastoma cells via receptor‐mediated transcytosis. The zwitterionic lipid (distearoyl phosphoethanol‐amine‐polycarboxybetaine lipid) in ALBTA promotes endosomal/lysosomal escape, and thus enhances the cytotoxicity of temozolomide and improves gene silencing efficiency of siTGF‐β. ALBTA significantly improves the immunosuppressive microenvironment and prolongs the survival time of glioma‐bearing mice. Moreover, ALBTA can be accurately traced by MRI in brain tumors. The study indicates that this immunochemotherapeutic platform can serve as a flexible and powerful synergistic system for treatment with brain tumors as well as other brain diseases in central nervous system.  相似文献   

20.
Small interfering RNA (siRNA) holds inherent advantages and great potential for treating refractory diseases. However, lack of suitable siRNA delivery systems that demonstrate excellent circulation stability and effective at‐site delivery ability is currently impeding siRNA therapeutic performance. Here, a polymeric siRNA nanomedicine (3I‐NM@siRNA) stabilized by triple interactions (electrostatic, hydrogen bond, and hydrophobic) is constructed. Incorporating extra hydrogen and hydrophobic interactions significantly improves the physiological stability compared to an siRNA nanomedicine analog that solely relies on the electrostatic interaction for stability. The developed 3I‐NM@siRNA nanomedicine demonstrates effective at‐site siRNA release resulting from tumoral reactive oxygen species (ROS)‐triggered sequential destabilization. Furthermore, the utility of 3I‐NM@siRNA for treating glioblastoma (GBM) by functionalizing 3I‐NM@siRNA nanomedicine with angiopep‐2 peptide is enhanced. The targeted Ang‐3I‐NM@siRNA exhibits superb blood–brain barrier penetration and potent tumor accumulation. Moreover, by cotargeting polo‐like kinase 1 and vascular endothelial growth factor receptor‐2, Ang‐3I‐NM@siRNA shows effective suppression of tumor growth and significantly improved survival time of nude mice bearing orthotopic GBM brain tumors. New siRNA nanomedicines featuring triple‐interaction stabilization together with inbuilt self‐destruct delivery ability provide a robust and potent platform for targeted GBM siRNA therapy, which may have utility for RNA interference therapy of other tumors or brain diseases.  相似文献   

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