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The invasion of nerves by cancer cells, or perineural invasion (PNI), is potentiated by the nerve microenvironment and is associated with adverse clinical outcomes. However, the cancer cell characteristics that enable PNI are poorly defined. Here, we generated cell lines enriched for a rapid neuroinvasive phenotype by serially passaging pancreatic cancer cells in a murine sciatic nerve model of PNI. Cancer cells isolated from the leading edge of nerve invasion showed a progressively increasing nerve invasion velocity with higher passage number. Transcriptome analysis revealed an upregulation of proteins involving the plasma membrane, cell leading edge, and cell movement in the leading neuroinvasive cells. Leading cells progressively became round and blebbed, lost focal adhesions and filipodia, and transitioned from a mesenchymal to amoeboid phenotype. Leading cells acquired an increased ability to migrate through microchannel constrictions and associated more with dorsal root ganglia than nonleading cells. ROCK inhibition reverted leading cells from an amoeboid to mesenchymal phenotype, reduced migration through microchannel constrictions, reduced neurite association, and reduced PNI in a murine sciatic nerve model. Cancer cells with rapid PNI exhibit an amoeboid phenotype, highlighting the plasticity of cancer migration mode in enabling rapid nerve invasion.
Assuntos
Amoeba , Tecido Nervoso , Neoplasias Pancreáticas , Camundongos , Animais , Neoplasias Pancreáticas/genética , Nervo Isquiático/metabolismo , Pâncreas/metabolismo , Tecido Nervoso/metabolismo , Movimento Celular/genética , Invasividade Neoplásica , Microambiente TumoralRESUMO
Animals integrate sensory information from the environment and display various behaviors in response to external stimuli. In Caenorhabditis elegans hermaphrodites, 33 types of sensory neurons are responsible for chemosensation, olfaction, and mechanosensation. However, the functional roles of all sensory neurons have not been systematically studied due to the lack of facile genetic accessibility. A bipartite cGAL-UAS system has been previously developed to study tissue- or cell-specific functions in C. elegans. Here, we report a toolkit of new cGAL drivers that can facilitate the analysis of a vast majority of the 60 sensory neurons in C. elegans hermaphrodites. We generated 37 sensory neuronal cGAL drivers that drive cGAL expression by cell-specific regulatory sequences or intersection of two distinct regulatory regions with overlapping expression (split cGAL). Most cGAL-drivers exhibit expression in single types of cells. We also constructed 28 UAS effectors that allow expression of proteins to perturb or interrogate sensory neurons of choice. This cGAL-UAS sensory neuron toolkit provides a genetic platform to systematically study the functions of C. elegans sensory neurons.
Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriais/metabolismoRESUMO
Deep-blue perovskite light-emitting diodes (PeLEDs) based on quasi-two-dimensional (quasi-2D) systems exist heightened sensitivity to the domain distribution. The top-down crystallization mode will lead to a vertical gradient distribution of quantum well (QW) structure, which is unfavorable for deep-blue emission. Herein, a thermal gradient annealing treatment is proposed to address the polydispersity issue of vertical QWs in quasi-2D perovskites. The formation of large-n domains at the upper interface of the perovskite film can be effectively inhibited by introducing a low-temperature source in the annealing process. Combined with the utilization of NaBr to inhibit the undesirable n=1 domain, a vertically concentrated QW structure is ultimately attained. As a result, the fabricated device delivers a narrow and stable deep-blue emission at 458â nm with an impressive external quantum efficiency (EQE) of 5.82 %. Green and sky-blue PeLEDs with remarkable EQE of 21.83 % and 17.51 % are also successfully achieved, respectively, by using the same strategy. The findings provide a universal strategy across the entire quasi-2D perovskites, paving the way for future practical application of PeLEDs.
RESUMO
The device performance of deep-blue perovskite light-emitting diodes (PeLEDs) is primarily constrained by low external quantum efficiency (EQE) especially poor operational stability. Herein, we develop a facile strategy to improve deep-blue emission through rational interface engineering. We innovatively reported the novel electron transport material, 4,6-Tris(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine (P-POT2T), and utilized a sequential wet-dry deposition method to form homogenic gradient interface between electron transport layer (ETL) and perovskite surface. Unlike previous reports that achieved carrier injection balance by inserting new interlayers, our strategy not only passivated uncoordinated Pb in the perovskite via P=O functional groups but also reduced interfacial carrier recombination without introducing new interfaces. Additionally, this strategy enhanced the interface contact between the perovskite and ETL, significantly boosting device stability. Consequently, the fabricated deep-blue PeLEDs delivered an external quantum efficiency (EQE) exceeding 5% (@ 460 nm) with an exceptional halftime extended to 31.3 minutes. This straightforward approach offers a new strategy to realize highly efficient especially stable PeLEDs.
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Buried interface modification can effectively improve the compatibility between interfaces. Given the distinct interface selections in perovskite solar cells (PSCs), the applicability of a singular modification material remains limited. Consequently, in response to this challenge, we devised a tailored molecular strategy based on the electronic effects of specific functional groups. Therefore, we prepared three distinct silane coupling agents, and due to the varying inductive effects of these functional groups, the electronic distribution and molecular dipole moments of the coupling agents are correspondingly altered. Among them, trimethoxy (3,3,3-trifluoropropyl)-silane (F3 -TMOS), which possesses electron-withdrawing groups, generates a molecular dipole moment directed toward the hole transport layer (HTL). This approach changes the work function of the HTL, optimizes the energy level alignment, reduces the open-circuit voltage loss, and facilitates carrier transport. Furthermore, through the buffering effect of the coupling agent, the interface strain and lattice distortion caused by annealing the perovskite are reduced, enhancing the stability of the tin-based perovskite. Encouragingly, tin PSCs treated with F3 -TMOS achieved a champion efficiency of 14.67 %. This strategy provides an expedient avenue for the design of buried interface modification materials, enabling precise molecular adjustments in accordance with distinct interfacial contexts to ameliorate mismatched energetics and enhance carrier dynamics.
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Blue perovskite light-emitting diodes (PeLEDs) are crucial avenues for achieving full-color displays and lighting based on perovskite materials. However, the relatively low external quantum efficiency (EQE) has hindered their progression towards commercial applications. Quasi-two-dimensional (quasi-2D) perovskites stand out as promising candidates for blue PeLEDs, with optimized control over low-dimensional phases contributing to enhanced radiative properties of excitons. Herein, the impact of organic molecular dopants on the crystallization of various n-phase structures in quasi-2D perovskite films. The results reveal that the highly reactive bis(4-(trifluoromethyl)phenyl)phosphine oxide (BTF-PPO) molecule could effectively restrain the formation of organic spacer cation-ordered layered perovskite phases through chemical reactions, simultaneously passivate those uncoordinated Pb2+ defects. Consequently, the prepared PeLEDs exhibited a maximum EQE of 16.6 % (@ 490â nm). The finding provides a new route to design dopant molecules for phase modulation in quasi-2D PeLEDs.
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Achieving efficient blue electroluminescence (EL) remains the fundamental challenge that impedes perovskite light-emitting diodes (PeLEDs) towards commercial applications. The bottleneck accounting for the inefficient blue PeLEDs is broadly attributed to the poor-emissive blue perovskite emitters based on either mixed halide engineering or reduced-dimensional strategy. Herein, we report the high-performing sky-blue PeLEDs (490â nm) with the maximum EQE exceeding 15 % by incorporating a molecular modifier, namely 4,4'-Difluorophenone, for significantly suppressing the non-radiative recombination and tuning of the low-dimensional phase distribution of quasi-2D blue perovskites, which represents a remarkable paradigm for developing the new generation of blue lighting sources.
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Perovskite nanocrystals (PeNCs) deliver size- and composition-tunable luminescence of high efficiency and color purity in the visible range. However, attaining efficient electroluminescence (EL) in the near-infrared (NIR) region from PeNCs is challenging, limiting their potential applications. Here we demonstrate a highly efficient NIR light-emitting diode (LED) by doping ytterbium ions into a PeNCs host (Yb3+ : PeNCs), extending the EL wavelengths toward 1000â nm, which is achieved through a direct sensitization of Yb3+ ions by the PeNC host. Efficient quantum-cutting processes enable high photoluminescence quantum yields (PLQYs) of up to 126 % from the Yb3+ : PeNCs. Through halide-composition engineering and surface passivation to improve both PLQY and charge-transport balance, we demonstrate an efficient NIR LED with a peak external quantum efficiency of 7.7 % at a central wavelength of 990â nm, representing the most efficient perovskite-based LEDs with emission wavelengths beyond 850â nm.
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Defect states play an important role in the photovoltaic performance of metal halide perovskites. Particularly, the passivation of surface defects has made great contributions to high-performance perovskite photovoltaics. This highlights the importance of understanding the surface defects from a fundamental level by developing more accurate and operando characterization techniques. Herein, a strategy to enable the surface carriers and photocurrent distributions on perovskite films to be visualized in the horizontal direction is put forward. The visual image of photocurrent distribution is realized by combining the static local distribution of carriers provided by scanning near-field optical microscopy with the dynamic transporting of carriers achieved via a scanning photocurrent measurement system. Taking a surface passivated molecule as an example, a comprehensive defect scene including static and dynamic as well as local and entire conditions is obtained using this strategy. The comprehensive analysis of the trap states in perovskite films is pioneered vertically and horizontally, which will powerfully promote the deep understanding of defect mechanisms and carrier behavior for the goal of fabricating high-performance perovskite optoelectronic devices.
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Signaling that instructs the migration of neurons needs to be tightly regulated to ensure precise positioning of neurons and subsequent wiring of the neuronal circuits. Wnt-Frizzled signaling controls neuronal migration in metazoans, in addition to many other aspects of neural development. We show that Caenorhabditis elegans VANG-1, a membrane protein that acts in the planar cell polarity (PCP) pathway, antagonizes Wnt signaling by facilitating endocytosis of the Frizzled receptors. Mutations of vang-1 suppress migration defects of multiple classes of neurons in the Frizzled mutants, and overexpression of vang-1 causes neuronal migration defects similar to those of the Frizzled mutants. Our genetic experiments suggest that VANG-1 facilitates Frizzled endocytosis through ß-arrestin2. Co-immunoprecipitation experiments indicate that Frizzled proteins and VANG-1 form a complex, and this physical interaction requires the Frizzled cysteine-rich domain. Our work reveals a novel mechanism mediated by the PCP protein VANG-1 that downregulates Wnt signaling through Frizzled endocytosis.
Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Polaridade Celular , Endocitose , Receptores Frizzled/metabolismo , Fosfoproteínas/metabolismo , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Movimento Celular , Larva/citologia , Complexos Multiproteicos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fosfoproteínas/química , Fosfoproteínas/genéticaRESUMO
BACKGROUND: Studies have shown diverse results regarding the association between H. pylori (HP) infection and the risk of malignancy. There is accumulating evidence relating HP infection to urological diseases. We investigated whether there was an association between HP-infected peptic ulcers and the subsequent risk of prostate cancer. METHODS: We collected HP-infected male patients from 1998 to 2008 from the Longitudinal Health Insurance Database (LHID). HP-infected patients were identified as those who had a diagnosis of peptic ulcers upon admission and received HP eradication therapy within 1 year after diagnosis. The date of HP infection diagnosis upon admission was defined as the index date. Patients aged < 20 years or with a cancer history were excluded. For each HP-infected patient, we selected four males without peptic ulcers or a history of HP eradication in the LHID for the comparison cohort according to propensity score matching by age, index year, and comorbidity. The risk of prostate cancer and associated risk factors was assessed by Cox proportional hazard regression. RESULTS: A total of 2620 HP infection treatment patients and 10,480 matched comparisons were selected. There were 36 patients in the HP-infected treatment cohort and 117 patients in the comparison cohort with documented prostate cancer development (1.52 and 1.21 per 1000 person-years, respectively). Compared to the comparison cohort, the HP infection cohort had a 1.26-fold increased prostate cancer risk in the Cox models after adjusting for matched-pairs (95% CI = 0.87-1.34). There were no significant differences in subsequent prostate cancer development between HP-infected treatment patients and the comparison cohort. CONCLUSION: Our findings showed no significant association between HP-infected peptic ulcers and the subsequent risk of prostate cancer. Further studies are warranted to investigate whether this observation is attributable to an HP eradication policy.
Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori , Úlcera Péptica/complicações , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Adulto , Idoso , Povo Asiático , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Medição de Risco , Fatores de Risco , Adulto JovemRESUMO
Spatial arrangement of neurite branching is instructed by both attractive and repulsive cues. Here we show that in C. elegans, the Wnt family of secreted glycoproteins specify neurite branching sites in the PLM mechanosensory neurons. Wnts function through MIG-1/Frizzled and the planar cell polarity protein (PCP) VANG-1/Strabismus/Vangl2 to restrict the formation of F-actin patches, which mark branching sites in nascent neurites. We find that VANG-1 promotes Wnt signaling by facilitating Frizzled endocytosis and genetically acts in a common pathway with arr-1/ß-arrestin, whose mutation results in defective PLM branching and F-actin patterns similar to those in the Wnt, mig-1 or vang-1 mutants. On the other hand, the UNC-6/Netrin pathway intersects orthogonally with Wnt-PCP signaling to guide PLM branch growth along the dorsal-ventral axis. Our study provides insights for how attractive and repulsive signals coordinate to sculpt neurite branching patterns, which are critical for circuit connectivity.
Assuntos
Proteínas de Caenorhabditis elegans/genética , Receptores Frizzled/genética , Proteínas do Tecido Nervoso/genética , Neurogênese/genética , Fosfoproteínas/genética , beta-Arrestina 1/genética , Actinas/genética , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Polaridade Celular/genética , Endocitose/genética , Netrinas , Neuritos/metabolismo , Neurônios/metabolismo , Via de Sinalização Wnt/genéticaRESUMO
The JPEG-XR encoding process utilizes two types of transform operations: Photo Overlap Transform (POT) and Photo Core Transform (PCT). Using the Device Porting Kit (DPK) provided by Microsoft, we performed encoding and decoding processes on JPEG XR images. It was discovered that when the quantization parameter is >1-lossy compression conditions, the resulting image displays chequerboard block artefacts, border artefacts and corner artefacts. These artefacts are due to the nonlinearity of transforms used by JPEG-XR. Typically, it is not so visible; however, it can cause problems while copying and scanning applications, as it shows nonlinear transforms when the source and the target of the image have different configurations. Hence, it is important for document image processing pipelines to take such artefacts into account. Additionally, these artefacts are most problematic for high-quality settings and appear more visible at high compression ratios. In this paper, we analyse the cause of the above artefacts. It was found that the main problem lies in the step of POT and quantization. To solve this problem, the use of a "uniform matrix" is proposed. After POT (encoding) and before inverse POT (decoding), an extra step is added to multiply this uniform matrix. Results suggest that it is an easy and effective way to decrease chequerboard, border and corner artefacts, thereby improving the image quality of lossy encoding JPEG XR than the original DPK program with no increased calculation complexity or file size.
RESUMO
Neurons remodel their connectivity in response to various insults, including microtubule disruption. How neurons sense microtubule disassembly and mount remodeling responses by altering genetic programs in the soma are not well defined. Here we show that in response to microtubule disassembly, the Caenorhabditis elegans PLM neuron remodels by retracting its synaptic branch and overextending the primary neurite. This remodeling required RHGF-1, a PDZ-Rho guanine nucleotide exchange factor (PDZ-RhoGEF) that was associated with and inhibited by microtubules. Independent of the myosin light chain activation, RHGF-1 acted through Rho-dependent kinase LET-502/ROCK and activated a conserved, retrograde DLK-1 MAPK (DLK-1/dual leucine zipper kinase) pathway, which triggered synaptic branch retraction and overgrowth of the PLM neurite in a dose-dependent manner. Our data represent a neuronal remodeling paradigm during development that reshapes the neural circuit by the coordinated removal of the dysfunctional synaptic branch compartment and compensatory extension of the primary neurite.
Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Fatores de Troca do Nucleotídeo Guanina/fisiologia , MAP Quinase Quinase Quinases/fisiologia , Mecanorreceptores/fisiologia , Microtúbulos/metabolismo , Regeneração Nervosa/fisiologia , Neurônios/fisiologia , Animais , Axônios/ultraestrutura , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Forma Celular , Colchicina/farmacologia , Ativação Enzimática , Genes Reporter , Larva , Sistema de Sinalização das MAP Quinases/fisiologia , Mecanorreceptores/ultraestrutura , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Mutação , Neuritos/metabolismo , Neuritos/ultraestrutura , Neurônios/ultraestrutura , Paclitaxel/farmacologia , Interferência de RNA , Proteínas Recombinantes de Fusão/metabolismo , Tato/fisiologia , Tubulina (Proteína)/deficiência , Tubulina (Proteína)/genética , Tubulina (Proteína)/fisiologia , Moduladores de Tubulina/farmacologia , Quinases Associadas a rho/fisiologiaRESUMO
Neuronal cargos are differentially targeted to either axons or dendrites, and this polarized cargo targeting critically depends on the interaction between microtubules and molecular motors. From a forward mutagenesis screen, we identified a gain-of-function mutation in the C. elegans α-tubulin gene mec-12 that triggered synaptic vesicle mistargeting, neurite swelling and neurodegeneration in the touch receptor neurons. This missense mutation replaced an absolutely conserved glycine in the H12 helix with glutamic acid, resulting in increased negative charges at the C-terminus of α-tubulin. Synaptic vesicle mistargeting in the mutant neurons was suppressed by reducing dynein function, suggesting that aberrantly high dynein activity mistargeted synaptic vesicles. We demonstrated that dynein showed preference towards binding mutant microtubules over wild-type in microtubule sedimentation assay. By contrast, neurite swelling and neurodegeneration were independent of dynein and could be ameliorated by genetic paralysis of the animal. This suggests that mutant microtubules render the neurons susceptible to recurrent mechanical stress induced by muscle activity, which is consistent with the observation that microtubule network was disorganized under electron microscopy. Our work provides insights into how microtubule-dynein interaction instructs synaptic vesicle targeting and the importance of microtubule in the maintenance of neuronal structures against constant mechanical stress.
Assuntos
Proteínas de Caenorhabditis elegans/genética , Degeneração Neural/genética , Transmissão Sináptica/genética , Vesículas Sinápticas/genética , Tubulina (Proteína)/genética , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Dendritos/genética , Dendritos/metabolismo , Dendritos/patologia , Dineínas/metabolismo , Exocitose , Humanos , Microtúbulos/metabolismo , Mutação de Sentido Incorreto , Degeneração Neural/patologia , Neuritos/metabolismo , Neuritos/patologia , Vesículas Sinápticas/metabolismo , Tubulina (Proteína)/metabolismoRESUMO
The ability of cancer cells to invade along nerves is associated with aggressive disease and diminished patient survival rates. Perineural invasion (PNI) may be mediated by nerve secretion of glial cell line-derived neurotrophic factor (GDNF) attracting cancer cell migration through activation of cell surface Ret proto-oncogene (RET) receptors. GDNF family receptor (GFR)α1 acts as coreceptor with RET, with both required for response to GDNF. We demonstrate that GFRα1 released by nerves enhances PNI, even in the absence of cancer cell GFRα1 expression. Cancer cell migration toward GDNF, RET phosphorylation, and MAPK pathway activity are increased with exposure to soluble GFRα1 in a dose-dependent fashion. Dorsal root ganglia (DRG) release soluble GFRα1, which potentiates RET activation and cancer cell migration. In vitro DRG coculture assays of PNI show diminished PNI with DRG from GFRα1(+/-) mice compared with GFRα1(+/+) mice. An in vivo murine model of PNI demonstrates that cancer cells lacking GFRα1 maintain an ability to invade nerves and impair nerve function, whereas those lacking RET lose this ability. A tissue microarray of human pancreatic ductal adenocarcinomas demonstrates wide variance of cancer cell GFRα1 expression, suggesting an alternate source of GFRα1 in PNI. These findings collectively demonstrate that GFRα1 released by nerves enhances PNI through GDNF-RET signaling and that GFRα1 expression by cancer cells enhances but is not required for PNI. These results advance a mechanistic understanding of PNI and implicate the nerve itself as a key facilitator of this adverse cancer cell behavior.
Assuntos
Adenocarcinoma/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Células 3T3 , Adenocarcinoma/patologia , Animais , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Técnicas de Cocultura , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Invasividade Neoplásica , Tecido Nervoso/metabolismo , Tecido Nervoso/patologia , Neoplasias Pancreáticas/patologia , Neoplasias do Sistema Nervoso Periférico/metabolismo , Neoplasias do Sistema Nervoso Periférico/patologia , Proto-Oncogene Mas , RNA Interferente Pequeno/genética , Neuropatia Ciática/metabolismo , Neuropatia Ciática/patologia , SolubilidadeRESUMO
We investigated the therapeutic efficacy of a replication-competent oncolytic vaccinia virus, GLV-1h153, carrying human sodium iodide symporter (hNIS), in combination with radioiodine in an orthotopic triple-negative breast cancer (TNBC) murine model. In vitro viral infection was confirmed by immunoblotting and radioiodine uptake assays. Orthotopic xenografts (MDA-MB-231 cells) received intratumoral injection of GLV-1h153 or PBS. One week after viral injection, xenografts were randomized into 4 treatment groups: GLV-1h153 alone, GLV-1h153 and (131)I (â¼ 5 mCi), (131)I alone, or PBS, and followed for tumor growth. Kruskal-Wallis and Wilcoxon tests were performed for statistical analysis. Radiouptake assay showed a 178-fold increase of radioiodine uptake in hNIS-expressing infected cells compared with PBS control. Systemic (131)I-iodide in combination with GLV-1h153 resulted in a 6-fold increase in tumor regression (24 compared to 146 mm(3) for the virus-only treatment group; P<0.05; d 40). We demonstrated that a novel vaccinia virus, GLV-1h153, expresses hNIS, increases the expression of the symporter in TNBC cells, and serves both as a gene marker for noninvasive imaging of virus and as a vehicle for targeted radionuclide therapy with (131)I.
Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/terapia , Vaccinia virus/fisiologia , Animais , Western Blotting , Linhagem Celular Tumoral , Feminino , Imunofluorescência , Humanos , Immunoblotting , Camundongos , Neoplasias de Mama Triplo Negativas/metabolismo , Vaccinia virus/genéticaRESUMO
Snake venom consists of toxin proteins with multiple disulfide linkages to generate unique structures and biological functions. Determination of these cysteine connections usually requires the purification of each protein followed by structural analysis. In this study, dimethyl labeling coupled with LC-MS/MS and RADAR algorithm was developed to identify the disulfide bonds in crude snake venom. Without any protein separation, the disulfide linkages of several cytotoxins and PLA2 could be solved, including more than 20 disulfide bonds. The results show that this method is capable of analyzing protein mixture. In addition, the approach was also used to compare native cytotoxin 3 (CTX III) and its scrambled isomer, another category of protein mixture, for unknown disulfide bonds. Two disulfide-linked peptides were observed in the native CTX III, and 10 in its scrambled form, X-CTX III. This is the first study that reports a platform for the global cysteine connection analysis on a protein mixture. The proposed method is simple and automatic, offering an efficient tool for structural and functional studies of venom proteins.
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Dissulfetos/análise , Venenos de Serpentes/química , Espectrometria de Massas em Tandem , Algoritmos , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Venenos de Cnidários/análise , Venenos de Cnidários/química , Bases de Dados de Proteínas , Isomerismo , Peptídeos/análiseRESUMO
Vascular endothelial growth factor (VEGF) expression is higher in triple-negative breast cancers (TNBC) compared to other subtypes and is reported to predict incidence of distant metastases and shorter overall survival. We investigated the therapeutic impact of a vaccinia virus (VACV) GLV-1h164 (derived from its parent virus GLV-1h100), encoding a single-chain antibody (scAb) against VEGF (GLAF-2) in an orthotopic TNBC murine model. GLV-1h164 was tested against multiple TNBC cell lines. Viral infectivity, cytotoxicity, and replication were determined. Mammary fat pad tumors were generated in athymic nude mice using MDA-MB-231 cells. Xenografts were treated with GLV-1h164, GLV-1h100, or PBS and followed for tumor growth. Viral infectivity was time- and concentration-dependent. GLV-1h164 killed TNBC cell lines in a dose-dependent fashion with greater than 90% cytotoxicity within 4 days at a multiplicity of infection of 5.0. In vitro, cytotoxicity of GLV-1h164 was identical to GLV-1h100. GLV-1h164 replicated efficiently in all cell lines with an over 400-fold increase in copy numbers from the initial viral dose within 4 days. In vivo, mean tumor volumes after 2 weeks of treatment were 73, 191, and 422 mm(3) (GLV-1h164, GLV-1h100, and PBS, respectively) (p < 0.05). Both in vivo Doppler ultrasonography and immuno-staining showed decreased neo-angiogenesis in GLV-1h164-treated tumors compared to both GLV-1h100 and PBS controls (p < 0.05). This is the first study to demonstrate efficient combination of oncolytic and anti-angiogenic activity of a novel VACV on TNBC xenografts. Our results suggest that GLV-1h164 is a promising therapeutic agent that warrants testing for patients with TNBC.
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Neovascularização Patológica/terapia , Vírus Oncolíticos/genética , Neoplasias de Mama Triplo Negativas/terapia , Vaccinia virus/genética , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/genética , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Neovascularização Patológica/genética , Neovascularização Patológica/virologia , Terapia Viral Oncolítica/métodos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/virologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Selective synthesis of 1- and 3-substituted 2-methoxyindenes from the carboalkoxylations of 2-ethynylbenzyl ethers is described; the former is obtained efficiently with P(t-Bu)2(o-biphenyl)AuCl/NaBARF in DCM/MS 4 Å whereas the latter is produced preferably with P(t-Bu)2(o-biphenyl)AuCl/AgNTf2 in pre-dried DCM. Both 1- and 3-substituted 2-indenyl ethers are subjected to ozone oxidations to afford two distinct carbonyl products. Our new data indicate that 1-substituted 2-indenyl ethers are generated from gold catalysts whereas their 3-substituted analogues arise from Brønsted acids.