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1.
The rational design of cancer‐targeted and bioresponsive drug delivery vehicles can enhance the anticancer efficacy of conventional chemotherapeutics and reduce their adverse side effects. However, the complexity of precise delivery and the ability to trigger drug release in specific tumor sites remain a challenging puzzle. Here, a sequentially triggered nanosystem composed of HER2 antibody with disulfide linkage as a surface decorator (HER2@NPs) is constructed for precise drug delivery and the simultaneous inhibition of cancer growth, migration, and invasion. The nanosystem actively accumulates in cancer cells, undergoes self‐immolative cleavage in response to biological thiols, and is degraded to form small nanoparticles. After internalization by receptor‐mediated endocytosis, the nanoparticles further disassemble under acidic conditions in the presence of lysozymes and cell lysates, leading to sequentially triggered drug release. The released payload triggers overproduction of reactive oxygen species and activates p53 and MAPKs pathways to induce cancer cell apoptosis. Moreover, HER2@NPs markedly suppress the migration and invasion of human bladder cancer cells at nontoxic concentrations. HER2@NPs demonstrate potent in vivo anticancer efficacy, but show no obvious histological damage to the major organs. Taken together, this study provides a valid tactic for the rational design of sequentially triggered nanosystems for precise drug delivery and cancer therapy.  相似文献   

2.
Developing a comprehensive platform which has both diagnosis and therapeutic strategies is necessary for efficient tumor treatment. In this work, a F uel I mproved micro R NA E xplorer (FIRE) probe with signal amplification capability is designed for sensitive detection of microRNA‐21 (miR‐21), which is upregulated in most tumor cells. Besides, FIRE could be loaded by polyethylenimine (PEI)‐modified gold nanorods (AuNR‐PEI) via facile electrostatic interaction, which could avoid the complicated processes commonly used to covalently conjugate nucleic acid probes onto AuNRs. The as‐fabricated AuNR‐PEI/FIRE system could efficiently distinguish tumor cells from non‐tumor cells. The fluorescence signals in MCF‐7 breast carcinoma and HeLa cervical carcinoma cells treated with AuNR‐PEI/FIRE are enhanced 7‐ and 4.5‐fold, respectively, compared with non‐amplification system. AuNR‐PEI/FIRE improves tumor detection ability in vivo and exhibits excellent tumor inhibition efficacy under the fluorescence imaging and photoacoustic imaging guided photothermal therapy. This is the first time to utilize the combined application of amplified nucleic acid detection and photothermal effect derived from gold nanorods together with PA imaging in a facile manner to provide a promising theranostic strategy for accurate diagnosis and tumor therapy.  相似文献   

3.
The nanoscale anisotropic patterns of bioactive ligands in the extracellular matrix regulate cell adhesion behaviors. However, the mechanisms of such regulation remain unclear. Here, RGD‐bearing gold nanorods (AuNRs) are conjugated with different aspect ratios (ARs, from 1 to 7) on cell culture substrates to decouple the effect of nanoscale anisotropic presentation of cell adhesive RGD peptides on cell adhesion. Compared with AuNRs with small ARs, AuNRs with large ARs significantly promote cell spreading, the alignment of the basal cytoskeletal structure, and nanopodia attachment. Furthermore, both ‐β3 and ‐β1 class integrins are recruited to AuNRs with large ARs, thereby promoting the development of focal adhesion toward fibrillar adhesion, whereas the recruitment of diverse integrins and the development of cell adhesion structures are hindered by small ARs AuNRs. The anisotropic presentation of ligands by large AR AuNRs better activates mechanotransduction signaling molecules. These findings are confirmed both in vitro and in vivo. Hence the enhanced mechanotransduction promotes osteogenic differentiation in stem cells. These findings demonstrate the potential use of well‐controlled synthetic nanoplatforms to unravel the fundamental mechanisms of cell adhesion and associated signaling at the molecular level and to provide valuable guidance for the rational design of biomaterials with tailored bioactive functions.  相似文献   

4.
A big challenge in cell culture is the non‐natural environment in which cells are routinely screened, making in vivo phenomena, such as cell invasion, difficult to understand and predict. To study cancer cell invasion, extracellular matrix (ECM) analogs with decoupled mechanical and chemical properties are required. Hyaluronic acid (HA)‐based hydrogels crosslinked with matrix‐metalloproteinase (MMP)‐cleavable peptides are developed to study MDA‐MB‐231 breast cancer cell invasion. Hydrogels are synthesized by reacting furan‐modified HA with bismaleimide peptide crosslinkers in a Diels–Alder click reaction. This new hydrogel takes advantage of the biomimetic properties of HA, which is overexpressed in breast cancer, and eliminates the use of nonadhesive crosslinkers, such as poly(ethylene glycol) (PEG). The crosslink (mechanical) and ligand (chemical) densities are varied independently to evaluate the effects of each parameter on cell migration. Increased crosslink density correlates with decreased MDA‐MB‐231 cell invasion whereas incorporation of MMP‐cleavable sequences within the peptide crosslinker enhances invasion. Increasing the ligand density of pendant GRGDS groups induces cell proliferation, but has no significant impact on invasion. By independently tuning the mechanical and chemical environment of ECM mimetic hydrogels, a platform is provided that recapitulates variable tissue properties and elucidates the role of the microenvironment in cancer cell invasion.  相似文献   

5.
纳米金棒(AuNRs)具有众多独特的属性,已广泛运用于生物医学领域,但其是否具有潜在的生物危害尚有争议.作者运用了激光扫描共聚焦显微镜技术、western blotting技术和其他分子生物学方法从细胞氧化应激的角度探讨了AuNRs诱导A549细胞产生自噬的分子机制.研究结果表明,4μg·mL-1的AuNRs处理6 h能够诱导A549细胞自噬标志蛋白LC3-Ⅱ表达增加,LC3蛋白从细胞核转移至细胞质并形成自噬小泡.进一步研究发现,AuNRs能够降低A549细胞线粒体膜电位、ATP含量、UCP2蛋白表达水平以及细胞抗氧化能力并导致活性氧蓄积,后者可能最终引起细胞产生自噬.而10 mmol·L-1抗氧化剂NAC能够逆转上述线粒体及细胞功能的改变,并抑制自噬的发生.这一研究为深入认识其生物危害及可能机制提供了有力的实验证据.  相似文献   

6.
Hyperactivity of the left stellate ganglion (LSG) contributes to the occurrence of ventricular arrhythmias (VAs). Recently, advances in neuromodulation have been achieved with near‐infrared (NIR)‐sensitive gold nanorods (AuNRs). Here, AuNRs are precisely regulated and applied to inhibit LSG function as well as neural activity, thus ameliorating myocardial ischemia‐induced VAs in a canine model. Specifically, the optimized AuNRs are synthesized and microinjected into the LSG of anesthetized dogs, and then followed by 5 min of NIR laser irradiation at a wavelength of 808 nm. The results demonstrate that 5 min NIR laser irradiation on the PEG‐AuNR‐treated LSG can reversely inhibit LSG function and neural activity, thereby ameliorating myocardial ischemia‐induced VAs. With the tissue‐penetrating NIR and excellent photothermal effect of AuNRs, this method may become a promising and noninvasive therapeutic strategy for suppressing hyperactivity of the cardiac sympathetic nerves, therefore benefiting patients with VAs in the future.  相似文献   

7.
The synergistic combination of photothermal and RNA interference therapy demonstrates great potential for effective treatment of metastatic breast cancer, but their efficacy is limited by the poor delivery efficiency to tumor. Herein, it is reported that an albumin biomimetic nanocorona (DRI‐S@HSA) can accomplish the high accumulation and deep penetration within tumor tissues, thereby holding great promise for synergistic therapy. DRI‐S@HSA is prepared by camouflaging human serum albumin (HSA) onto an IR‐780 and small interfering RNA‐loaded cell‐penetrating peptide nanoassembly (DRI‐S). In metastatic 4T1 breast cancer cells, DRI‐S@HSA can be largely internalized, and cause significant inhibition on cell migration and proliferation in combination with laser irradiation. Surprisingly, in vivo, the albumin camouflage in DRI‐S@HSA produces a 2.5‐fold enhancement on tumor accumulation compared to the undecorated DRI‐S, and dramatically improves the deep penetration capacity in tumor mass. Moreover, a single DRI‐S@HSA treatment plus 808 nm laser irradiation results in an 83.6% inhibition on tumor growth and efficient prevention of lung metastases. Taken together, the findings can provide an encouraging biomimetic tumor‐targeted drug delivery strategy to inhibit tumor progression and prevent lung metastases of breast cancer.  相似文献   

8.
The poor drug delivery to primary and metastatic tumors of breast cancer remains a great challenge for effective antimetastasis therapy. Herein, a tumor microenvironment‐activated cabazitaxel micelles decorated with legumain‐specific melittin (TCM‐legM) are rationally designed for programed targeting of breast cancer metastasis. TCM‐legM is quiescent in blood circulation, but can be specifically activated by the highly expressed legumain in tumor microenvironments to improve their specific targeting and deep penetrating to primary or metastatic tumors. Thereafter, the activated TCM‐legM can be efficiently internalized by cancer cells and motivate the rapid pH‐responsive drug release for antimetastasis therapy. In metastatic 4T1 breast cancer cells, TCM‐legM presents significant inhibition on the proliferation, migration, and invasion activities. In vivo, TCM‐legM can be effectively delivered to both primary and metastatic tumors of breast cancer with deep tumor penetration and efficient cellular internalization, thereby resulting in a notable reduction of tumor growth and producing a 93.4% suppression of lung metastasis. Taken together, the rationally designed TCM‐legM can provide an intelligent drug delivery strategy to enhance the medical performance on treating breast cancer metastasis.  相似文献   

9.
Mesoporous CoNi@Au core@shell nanorods are synthesized as magnetic drug nanocarriers by electrodeposition using ionic liquid‐in‐aqueous microemulsions. Mesoporous nanorods present a highly effective area (186 m2 g?1) and magnetic character that allows their manipulation, concentration, and retention by applying a magnetic field. The nanorods have been functionalized with thiol‐poly(ethyleneglycol) molecules, and molecules of Irinotecan, a drug used in chemotherapy, are retained in both the lattice of the linked thiol‐poly(ethyleneglycol) molecules and inside the interconnected nanorods pores. The nanorods' mesoporous character allows a high drug‐loading capability and magnetic behavior that allows the drug's controlled release. A high cellular viability of HeLa cells is obtained after their incubation with the nanorods functionalized with thiol‐poly(ethyleneglycol). However, when the nanorods function as carriers for Irinotecan, significant cell death is occurred when HeLa cells are incubated with the functionalized, drug‐loaded nanorods. Cell death is also produced by applying an alternating magnetic field due to both the effect of the release of Irinotecan from the carrier as to mechanical damage of cells by nanorods subjected to the effect of a magnetic field. The proposal to used mesoporous magnetic nanorods as drug carriers can thus dramatically reduce the amounts of both nanocarrier and drug needed to efficiently destroy cancer cells.  相似文献   

10.
Metastasis is the leading cause of mortality in cancer patients. Underlying this process is the invasion and colonization of cancer cells into healthy tissues. Engineered hydrogel models of tumor microenvironments present an opportunity to understand the microenvironmental determinants of cellular invasion. The biochemical and mechanical cues, presented in the form of adhesion sites, degradable cues, matrix stiffness, and architecture, have significant effects on the extent of cancer cell migration, and the mechanisms employed by these cells to move through their matrix. Coculture with stromal cells such as cancer associated fibroblasts, endothelial cells, and immune cells that are associated with poor prognosis demonstrate that these cells exacerbate cancer cell invasion. With these models, researchers aim not only to recapitulate known cancer cell behaviors in a dish, but also to uncover new insights into mechanisms underlying these phenomena, paving the way for novel treatment strategies. In this perspective, the design of engineered models that are used to study cancer cell invasion and metastasis in vitro is discussed. To this end, the authors seek to understand and put into perspective: do these models reveal relevant mechanisms of cancer cell migration, or are they simply pretty pictures with little biological translatability?  相似文献   

11.
The nanomechanics of cells have been proven to play important roles in regulating cell behaviors. However, conventional measurement of cell nanomechanics that is processed on uniform surfaces lacks the control of cell morphology, which is reported to significantly influence the cell nanomechanics. This study prepares the micropatterned surfaces using photolithographic micropatterning of photoreactive poly(vinyl alcohol) on cell‐culture polystyrene plates to provide controllable and reproducible cell morphology. The nanomechanics of osteoblasts (NHOst), mesenchymal stem cells (MSCs), and osteosarcoma cell line (MG‐63) are compared on micropatterns. Cell stiffness increases with increase of spreading area due to the ordering of cytoskeleton. Disrupting F‐actin assembly reduces cell stiffness. Meanwhile, cell spreading area influences the expression of phosphoezrin that affects cell surface roughness. Rough membrane is accompanied with high non‐specific adhesion force and migration rate. The influence of spreading area on cancer cell nanomechanics is not as evident as that of normal cells indicating cancer cells behave less dependently on their microenvironment compared to normal cells. The findings of this study suggest that the nanomechanical differences between normal and cancer cells can be used as a biomarker to enhance the diagnosis of cancers. The use of micropatterns should be very useful to compare the nanomechanics of cells.  相似文献   

12.
Lung cancer is a serious threat to human health with the highest morbidity and mortality; metastatic lung cancer accounts for a majority of cancer-related deaths. Hence, there is considerable interest in developing efficient lung-targeted drug delivery systems to improve overall survival and quality of life of lung cancer patients. Based on the lung-targeting characteristics of cubic crosslinked cyclodextrin metal–organic framework (CDF) nanoparticles, this study shows the synthesis of a nanoplatform using RGD-functionalized CDF to co-deliver low-molecular-weight heparin (LMWH) and doxorubicin (DOX) for treatment of lung cancer. Rational design of the DOX-loaded RGD-CDF-LMWH nanoplatform (RCLD) is carried out. RCLD nanoparticles are efficiently targeted to lung tumors following intravenous administration; RCLD accumulation in the lung is 5.8 times greater than that in the liver. Moreover, RCLD inhibits migration and invasion of cancer cells in vitro and significantly diminishes lung tumor nodule count and area of spread in human A549 and murine B16F10 lung cancer models in vivo. Furthermore, RCLD does not show serum enzyme or histopathologic indicators of tissue damage or adverse hematologic effects. Therefore, the multiple antitumor activities of this novel RCLD nanoplatform, alongside its safety profile for normal tissues, strongly support its use for targeted treatment of lung cancer.  相似文献   

13.
Nanorod‐based drug delivery systems have attracted great interest because of their enhanced cell internalization capacity and improved drug loading property. Herein, novel mesoporous silica nanorods (MSNRs) with different lengths are synthesized and used as nanocarriers to achieve higher drug loading and anticancer activity. As expected, MSNRs‐based drug delivery systems can effectively enhance the loading capacity of drugs and penetrate into tumor cells more rapidly than spherical nanoparticles due to their greater surface area and trans‐membrane transporting rates. Interestingly, these tailored MSNRs also enhance the cellular uptake of doxorubicin (DOX) in cancer cells, thus significantly enhancing its anticancer efficacy for hundreds of times by inducing of cell apoptosis. Internalized MSNRs‐DOX triggers intracellular reactive oxygen species (ROS) overproduction, which subsequently activates p53 and mitogen‐activated protein kinases (MAPKs) pathways to promote cell apoptosis. MSNRs‐DOX nanosystem also shows prolonged blood circulation time in vivo. In addition, MSNRs‐DOX significantly inhibits in vivo tumor growth in nude mice model and effectively reduced its in vivo toxicity. Therefore, this study provides an effective and safe strategy for designing chemotherapeutic agents for precise cancer therapy.  相似文献   

14.
Directed cell migration is essential for many biological processes, such as embryonic development or cancer progression. Cell contractility and adhesion to the extracellular matrix are known to regulate cell locomotion machinery. However, the cross‐talk between extrinsic and intrinsic factors at the molecular level on the biophysical mechanism of three dimensional (3D)‐directed cell migration is still unclear. In this work, a novel physiologically relevant in vitro model of the extracellular microenvironment is used to reveal how the topological anisotropy of the extracellular matrix synergizes with actomyosin contractility to modulate directional cell migration morphodynamics. This study shows that cells seeded on polarized 3D matrices display asymmetric protrusion morphodynamics and in‐vivo‐like phenotypes. It is found that matrix anisotropy significantly enhances cell directionality, but strikingly, not the invasion distance of cells. In Rho‐inhibited cells, matrix anisotropy counteracts the lack of actomyosin‐driven forces to stabilize cell directionality suggesting a myosin‐II‐independent mechanism for cell guidance. Finally, this study shows that on isotropic 3D environments, cell directionality is independent of actomyosin contractility. Altogether, this study provides novel quantitative data on the biomechanical regulation of directional cell motion and shows the important regulatory role of matrix anisotropy and actomyosin forces to guide cell migration in 3D microenvironments.  相似文献   

15.
Evidence shows that the enzyme human cytochrome P450 1A1 (CYP1A1) is associated with cancer; indeed, it is shown to play a key role in the occurrence of many cancers. Therefore, the molecular imaging of CYP1A1 in cells is of great significance for revealing the process of cancer development. Herein, a chemosensor, DCBEM, is reported that is able to selectively recognize CYP1A1 and achieve long-term labeling of the enzyme through an enzymolysis cascade reaction. The design of DCBEM relies on the reaction between the highly electrophilic intermediate (quinone methide) and the enzyme, which forms a fluorescent label with CYP1A1 via covalent bonding. The chemosensor reveals excellent specificity toward CYP1A1 and achieves high-resolution monitoring of cell migration with a strong retention capacity in vivo (up to 4 days). Further, using DCBEM, the pathways of invasion of colon cancer and breast cancer cells are successfully visualized in living mice. This method of labeling enzymes provides a simple and efficient way to render ordinary fluorescent chemosensors suitable for the long-term tracking of cancer cells, for which such molecular tools are currently lacking.  相似文献   

16.
A significant percentage of human cancers harbor missense mutations in the TP53 gene and express highly stabilized mutant p53 protein (mutp53) with tumor‐promoting gain‐of‐function (GOF) properties. Inducing mutp53 degradation is a viable precision anti‐tumor therapeutic strategy. Based on the previously reported finding that a zinc‐curcumin compound induced mutp53 degradation, a series of ZnFe nanoparticles (ZnFe NPs) are synthesized and it is found that ZnFe‐4, with an Zn:Fe ratio of 1:2, exhibits outstanding mutp53‐degrading capability. ZnFe‐4 induced ubiquitination‐mediated proteasomal degradation of several different mutp53 species, but not the wild‐type p53 protein. Cellular internalization, intracellular Zn++ elevation and increased ROS are all necessary for ZnFe‐4‐induced mutp53 degradation. Degradation of mutp53 by ZnFe‐4, abrogated mutp53‐manifested GOF, leading to increased p21 expression, cell cycle arrest, reduced cell proliferation and cell migration, and cell demise. ZnFe‐4 also sensitized to cisplatin‐elicited killing in p53 S241F ES‐2 ovarian cancer cells, and dramatically improved the therapeutic efficacy of cisplatin in a subcutaneous ES‐2 tumor model. The potential clinical utility of ZnFe‐4 is further demonstrated in an orthotopically‐implanted p53 Y220C patient‐derived xenograft (PDX) breast cancer model. ZnFe‐4 is the first reported mutp53‐degrading nanomaterial, and further materials engineering may lead to the development of zinc‐based nanoparticles with minimal toxicity and maximized mutp53‐degrading capability.  相似文献   

17.
Cell‐based drug delivery systems are a promising platform for tumor‐targeted therapy due to their high drug‐loading capacities and inherent tumor‐homing abilities. However, the real‐time tracking of these carrier cells and controlled release of the encapsulated drugs are still challenging. Here, ultrasound‐activatable cell bombs are developed by encapsulating doxorubicin (DOX) and phase transformable perfluoropentane (PFP) into hollow mesoporous organosilica nanoparticles (HMONs) to prepare DOX/PFP‐loaded HMONs (DPH), followed by internalization into macrophages (RAW 264.7 cells). The resulting cell bombs (DPH‐RAWs) can maintain viability and actively home to the tumor. Especially, their migration can be tracked in real time using ultrasound due to the vaporization of a small portion of PFP during cell incubation at 37 °C. After accumulation at the tumor site, the further vaporization of remaining PFP can be triggered by a short‐pulsed high intensity focused ultrasound (HIFU) sonication, resulting in the generation of several large microbubbles, which destroys DPH‐RAWs and allows drug release out of these cells. The DPH‐RAWs combined with short‐pulsed HIFU sonication significantly inhibit tumor growth and prolong survival of tumor‐bearing mice. In conclusion, this study provides a new approach to cell‐based drug delivery systems for real‐time tracking of their migration and targeted cancer treatment.  相似文献   

18.
Localized surface plasmon resonance (LSPRs) shown by gold nanorods (AuNRs) has several applications in photocatalysis, sensing, and biomedicine. The combination of AuNRs with Polydopamine (PDA) shells results in a strong photo-thermal effect, making them appealing nanomaterials for biomedical applications. However, the precise roles and relative contributions of plasmonic effects in gold, and light-to-heat conversion in PDA are still debated. Herein, a hybrid nanoplatform made by an AuNR core surrounded by a polydopamine (PDA) shell is synthesized, and its photocatalytic behavior is studied. Synthesis is based on a seed-mediated growth followed by the further self-polymerization of dopamine hydrochloride (DA) on the surface of the AuNRs, and the effect of the thickness of the PDA shell on the plasmon response of the composite is the main examined parameter. Photocatalytic performance is tested toward Rhodamine 6G (Rh6G), with the nanocomposites achieving better performance than bare AuNRs and bare PDA nanoparticles. The degradation of 54% of Rh6G initial concentration is achieved within 60 min of irradiation with a catalyst concentration of 7.4 µg mL−1. Photodegradation kinetics, time-resolved spectroscopy, and finite-element-method simulations of plasmons show that AuNRs plasmons, coupled with the low thermal conductivity of PDA, provide slow thermalization, while enhancing the charge carrier transfer.  相似文献   

19.
目的:研究RNAi沉默整合素连接激酶(integrin-linked kinase,ILK)基因对人膀胱癌BIU-87细胞裸鼠皮下成瘤的影响。方法:构建4条针对ILK基因的特异性miRNA干扰载体和1条阴性对照载体,并利用脂质体转染法将其转染BIU-87细胞,并筛选获得稳定转染细胞株。利用RT-PCR和Western blot分别从mRNA和蛋白水平检测抑制效果。将10只裸鼠随机分为2组,皮下分别接种转染组细胞和未转染组细胞,观察瘤体的生长情况,并于接种4周后处死裸鼠,测量其瘤体体积和重量,并将瘤体做HE染色,观察瘤体病理情况。结果:转染组细胞ILK的表达明显受到抑制,以miR-3组的抑制效率最高。裸鼠皮下成瘤实验检测发现:两组均有瘤体形成,未转染组较转染组瘤体生长快,未转染组体积平均为:289.56±36.49mm3,转染组为:56.67±4.32mm3。瘤体重量分别为:1.265±0.02 g和0.518±0.03g。转染组与未转染组相比差异具有统计学意义(P〈0.05)。结论:利用RNAi技术能有效抑制靶基因ILK的表达,从而降低膀胱癌细胞的体内的增殖能力。  相似文献   

20.
Oxoplatinum (USSR) caused a more pronounced anticancer effect than platidiam (CSSR) when treating nude mice with the transplantable human melanoma. Moderate lymphopenia was found with therapeutic doses of oxoplatinum and platidiam, but there was no direct inhibition of the energy metabolism of lymphocytes in the peripheral blood. In the cancer cells and in the lymphocytes infiltrating the tumour oxoplatinum caused a significant decrease in the alpha-GPDG activity realizing the binding of the glycolysis and oxidation which might evidence for a definite selective action of oxoplatinum on the human melanoma.  相似文献   

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