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Herein, a new centrosymmetric phase Na4Nb8P4O32 (referred to as CS-Na4Nb8P4O32) was obtained by a molten salt method, which is a polymorph of niobium phosphate bronze Na4Nb8P4O32. CS-Na4Nb8P4O32 displays high structural similarity to the noncentrosymmetric Na4Nb8P4O32 phase (referred to as NCS-Na4Nb8P4O32): Distorted NbO6 octahedra are corner-coordinated to form ReO3-type layers, which are further joined together by isolated PO4 tetrahedra. However, two polymorphous phases adopt different packings of structural units, resulting in distinct symmetries. NbO3 layers and PO4 tetrahedra are reversely arranged along the crystallographic a direction in CS-Na4Nb8P4O32, thereby producing a centrosymmetric structure. The reverse packing cancels out all contributions of dipole moments originating from the distorted NbO6 octahedra; NCS-Na4Nb8P4O32 exhibits the C2-rotation distribution of NbO3 layers and PO4 tetrahedra, thus generating a noncentrosymmetric and polar structure. The C2-rotation packing of structural units brings a constructive addition of the dipole moments, further obtaining large calculated independent second harmonic generation susceptibilities. The study of structural evolution deduced by the packings of structural units in polymorphous Na4Nb8P4O32 might provide valuable insights into polymorphism and structural regulation.
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Replacing alkali metals (K, Na atoms) by an alkaline-earth metal (Ba atom), α-Ba3Sc2(BO3)4 (high-temperature phase) is successfully obtained by a molten salt method, taking Ba2K1.6Na0.4Sc2(BO3)4 as the parent template. Although both of them exhibit similar layered structures composed of ScO6 and BO3 units, α-Ba3Sc2(BO3)4 shows largely distorted ScO6 octahedra (Δd = 0.56) forced by the uniform tension of a larger space effect from BaO12 polyhedrons, rather than regular ScO6 octahedra like in Ba2K1.6Na0.4Sc2(BO3)4. Experimental measurements and calculated analyses elucidate that distorted ScO6 octahedra in α-Ba3Sc2(BO3)4, displaying a second-order Jahn-Teller (SOJT) effect, enlarge the experimental birefringence up to 0.14@550 nm, while Ba2K1.6Na0.4Sc2(BO3)4 with regular ScO6 octahedra only shows Δn = 0.11 under the same condition. In addition, other optical and thermal properties of the two title compounds were characterized. The experimental results indicate that Ba2K1.6Na0.4Sc2(BO3)4 and α-Ba3Sc2(BO3)4 are promising birefringent materials.
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BACKGROUND: Microglia have been implicated in the pathogenesis of radiation-induced brain injury (RIBI), which severely influences the quality of life during long-term survival. Recently, irradiated microglia were speculated to present an aging-like phenotype. Long noncoding RNAs (lncRNAs) have been recognized to regulate a wide spectrum of biological processes, including senescence; however, their potential role in irradiated microglia remains largely uncharacterized. METHODS: We used bioinformatics and experimental methods to identify and analyze the senescence phenotype of irradiated microglia. Western blotting, enzyme-linked immunosorbent assays, immunofluorescence, and quantitative real-time reverse transcription-polymerase chain reaction were performed to clarify the relationship between the radiation-induced differentially expressed lncRNAs (RILs) and the distinctive molecular features of senescence in irradiated microglia. RESULTS: We found that the senescence of microglia could be induced using ionizing radiation (IR). A mutual regulation mode existed between RILs and three main features of the senescence phenotype in irradiated microglia: inflammation, the DNA damage response (DDR), and metabolism. Specifically, for inflammation, the expression of two selected RILs (ENSMUST00000190863 and ENSMUST00000130679) was dependent on the major inflammatory signaling pathways of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK). The two RILs modulated the activation of NF-κB/MAPK signaling and subsequent inflammatory cytokine secretion. For the DDR, differential severity of DNA damage altered the expression profiles of RILs. The selected RIL, ENSMUST00000130679, promoted the DDR. For metabolism, blockade of sterol regulatory element-binding protein-mediated lipogenesis attenuated the fold-change of several RILs induced by IR. CONCLUSIONS: Our findings revealed that certain RILs interacted with senescence in irradiated microglia. RILs actively participated in the regulation of senescence features, suggesting that RILs could be promising intervention targets to treat RIBI.
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Senescencia Celular/efectos de la radiación , Microglía/metabolismo , ARN Largo no Codificante/metabolismo , Transducción de Señal/efectos de la radiación , Animales , Línea Celular , Ratones , Microglía/efectos de la radiación , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , ARN Largo no Codificante/genética , Radiación IonizanteRESUMEN
In order to evaluate the biomechanical stability of titanium alloy screw with different structural parameters under bone remodeling, some three-dimensional finite element models were established and the bone remodeling process after implanting the screw was simulated. Three-dimensional finite element models consist of bone and screw with different lengths and diameters. Bone remodeling process was simulated by user-defined subroutine. It is found that the stress on the bone is concentrated on the groove and root of the internal thread. The screw stress is mainly on the beginning of the thread, and the whole stress decreases along the long axis of the screw. The stress distribution trend of bone and screw did not change significantly during the bone remodeling. The maximum equivalent stress value was different, the maximum equivalent stress on the screw and cancellous bone increased while the maximum equivalent stress value on the cortical bone decreased.
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Remodelación Ósea , Tornillos Óseos , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Estrés Mecánico , TitanioRESUMEN
Precise and reliable liquid delivery is vital for microfluidic applications. Here, we illustrate the design, fabrication, characterization, and application of a portable, low cost, and robust micropump, which brings solution to stable liquid delivery in microfluidic environment. The pump is designed with three optional speeds of different pumping flow rates, and it can be simply actuated by spring-driven mechanism. The different flow rates of the pump are realized via passive microvalves in a compact microfluidic chip, which is installed in the pump. Importantly, the membrane structures of the microvalves allow accurate liquid control, and stable flow rates can be achieved via a spring setup. The proposed pump is applied to continuously and stably infuse microbead suspension into an inertial microfluidic chip, and good particle focusing is realized in the spiral channel of the inertial microfluidic chip. The proposed portable, self-powered, and cost-efficient pump is crucial for microfluidic lab-on-a-chip system integration, which may facilitate microfluidic application for precise liquid delivery, control, measurement, and analysis.
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Técnicas Analíticas Microfluídicas/instrumentación , Microfluídica/instrumentación , Diseño de Equipo , Dispositivos Laboratorio en un Chip , Presión , SilicioRESUMEN
Spontaneous tumor regression can be observed in many tumors, however, studies related to the altered expression of lncRNA in spontaneous glioma regression are limited, and the potential contributions of lncRNAs to spontaneous glioma regression remain unknown. To investigate the biological roles of lncRNA-135528 in spontaneous glioma regression. The cDNA fragment of lncRNA-135528 was obtained by rapid-amplification of cDNA ends (RACE) technology and cloned into the plvx-mcmv-zsgreen-puro vector. Additionally, we stably silenced or overexpressed lncRNA-135528 in G422 cells by transfecting with siRNA against lncRNA-135528 or lncRNA-135528 overexpression plasmid. Then, we examined lncRNA-135528 overexpressing and lncRNA-135528 silencing on glioma cells and its effects on CXCL10 and JAK/STAT pathways. The main findings indicated that lncRNA-135528 promoted glioma cell apoptosis, inhibited cell proliferation and arrested cell cycle progression; the up-regulation of lncRNA135528 led to significantly increased CXCL10 levels and the differential expression of mRNA associated with JAK/STAT pathway in glioma cells. lncRNA-135528 can inhibit tumor progression by up-regulating CXCL10 through the JAK/STAT pathway.
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Quimiocina CXCL10/genética , Quinasas Janus/genética , Regresión Neoplásica Espontánea/genética , ARN Largo no Codificante/metabolismo , Factores de Transcripción STAT/genética , Activación Transcripcional , Animales , Apoptosis , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Perfilación de la Expresión Génica , Silenciador del Gen , Glioma/genética , Glioma/metabolismo , Glioma/patología , Humanos , Quinasas Janus/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Regresión Neoplásica Espontánea/patología , Regresión Neoplásica Espontánea/fisiopatología , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/genética , ARN Mensajero/metabolismo , Factores de Transcripción STAT/metabolismo , Transducción de Señal/genéticaRESUMEN
Based on successful targeting to the αvß3 integrin of cyclic arginine-glycine-aspartic acid (cRGD), cRGD-conjugated small interfering RNA (siRNA) exhibits tumor targeting and has become a new treatment strategy for solid tumors. However, the nephrotoxicity caused by its renal retention limits its clinical application. Here, we evaluated the protective effect of Gelofusine against cRGD-conjugated siRNA-induced nephrotoxicity in mice. Male Kunming mice (six per group) were either co-injected with Gelofusine and cRGD-siRNA or injected with cRGD-siRNA alone. After administration of these treatments five times, creatinine and blood urea nitrogen (BUN) levels were determined. Hematoxylin-eosin staining (HE staining) and transferase dUTP nick end labeling (TUNEL) analysis were used to compare the difference in renal damage between the groups. Additionally, fluorescence imaging was used to observe the distribution of cRGD-siRNA in vivo. The group co-injected with Gelofusine and cRGD-siRNA displayed lower creatinine and BUN levels than the cRGD-siRNA-alone group and showed less renal damage upon HE staining and TUNEL analysis. Gelofusine decreased the retention time and accelerated the elimination of cRGD-siRNA from the organs, as observed in the fluorescence images. These data indicate that Gelofusine significantly increased the excretion of cRGD-conjugated siRNA and reduced the associated renal damage.
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Lesión Renal Aguda/prevención & control , Riñón/efectos de los fármacos , Poligelina/uso terapéutico , ARN Interferente Pequeño/inmunología , Eliminación Renal/efectos de los fármacos , Lesión Renal Aguda/inmunología , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Humanos , Integrina alfaVbeta3/genética , Riñón/metabolismo , Masculino , Ratones , Péptidos Cíclicos/administración & dosificación , Péptidos Cíclicos/química , Péptidos Cíclicos/toxicidad , Poligelina/farmacología , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , Distribución TisularRESUMEN
OBJECTIVE: To assess the efficacy and safety of Reduqing granules in patients with common cold with wind-heat syndrome (CCWHS). METHODS: A randomized, double-blind, double-dummy, parallel, positive- controlled trial included 72 CCWHS patients was performed. The participants were randomly assigned to two groups, Reduqing (RDQ) group and Lianhuaqingwen (LHQW) group, in a 1:1 ratio. Patients in RDQ group received Reduqing granules and dummy Lianhuaqingwen capsules three times a day and patients in LHQW group received Lianhuaqingwen capsules and dummy Reduqing granules three times daily. The duration of treatment and follow-up were four days. RESULTS: There were no statistically significant differences in total markedly effective rate and total effective rate between RDQ group and LHQW group after treatment. Traditional Chinese Medicine (TCM) symptom score was significantly reduced after treatment in RDQ group, as well as in LHQW group. However, the difference of change in TCM symptom score between two groups was not statistically significant (P > 0.05). There were no significant differences between two groups in the median time to fever relief [RDQ group (4 ± 8) h vs LHQW group (4 ± 5) h] or the median time to fever clearance (RDQ group 47 h vs LHQW 36 h). No serious adverse events were reported during the study. CONCLUSION: Compared with Lianhuaqingwen capsules, Reduqing granules achieved similar therapeutic effect in the treatment of CCWHS and no drug-related adverse events were reported during the study. Therefore, Reduqing granules might be effective and safe in the treatment of CCWHS.
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Resfriado Común/tratamiento farmacológico , Medicamentos Herbarios Chinos/administración & dosificación , Adolescente , Adulto , Anciano , Método Doble Ciego , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Fiebre/tratamiento farmacológico , Humanos , Masculino , Medicina Tradicional China , Persona de Mediana Edad , Resultado del Tratamiento , Adulto JovenRESUMEN
To evaluate the biomechanical stability of femoral shaft fracture fixation using different locking plates combined with different screw layout, for two different fracture settings, we build six groups different length locking plate combined with different screw number and different screw layout, fix with the fracture models respectively, and use the biomechanical finite element method to analysis the models. Then we attain the axial displacement and equivalent stress distribution of the internal fixation system under the action of axial load. The research shows that filling relatively softer material in femoral fracture can guarantee the stability of the internal fixation system, the long plate combined with less screw layout is obviously better than the short plate combined with the all screw layout, the same length plate combined with the selective screw layout is more effective than combined with the all screw layout. And plate combined with screws fixed in four threaded hole of distal fracture make the screw system stress disperse, and avoiding screw fixed in proximal fracture can alleviate the stress concentration of screws.
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Tornillos Óseos , Fracturas del Fémur/cirugía , Análisis de Elementos Finitos , Fijación Interna de Fracturas , Fenómenos Biomecánicos , Placas Óseas , HumanosRESUMEN
RNAi technology is taking strong position among the key therapeutic modalities, with dozens of siRNA-based programs entering and successfully progressing through clinical stages of drug development. To further explore potentials of RNAi technology as therapeutics, we engineered and tested VEGFR2 siRNA molecules specifically targeted to tumors through covalently conjugated cyclo(Arg-Gly-Asp-d-Phe-Lys[PEG-MAL]) (cRGD) peptide, known to bind αvß3 integrin receptors. cRGD-siRNAs were demonstrated to specifically enter and silence targeted genes in cultured αvß3 positive human cells (HUVEC). Microinjection of zebrafish blastocysts with VEGFR2 cRGD-siRNA resulted in specific inhibition of blood vessel growth. In tumor-bearing mice, intravenously injected cRGD-siRNA molecules generated no innate immune response and bio-distributed to tumor tissues. Continuous systemic delivery of two different VEGFR2 cRGD-siRNAs resulted in down-regulation of corresponding mRNA (55 and 45%) and protein (65 and 45%) in tumors, as well as in overall reduction of tumor volume (90 and 70%). These findings demonstrate strong potential of cRGD-siRNA molecules as anti-tumor therapy.
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Neoplasias/terapia , Péptidos Cíclicos/administración & dosificación , Interferencia de ARN , ARN Interferente Pequeño/administración & dosificación , Animales , Línea Celular Tumoral , Células Cultivadas , Femenino , Técnicas de Silenciamiento del Gen , Células HeLa , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/irrigación sanguínea , Neovascularización Fisiológica , Péptidos Cíclicos/análisis , Péptidos Cíclicos/química , ARN Interferente Pequeño/química , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Pez Cebra/embriologíaRESUMEN
Ab initio calculations on the anisotropic relaxation of a CuO/TiO2 surface under electric fields and the visible light absorption of these relaxed surfaces are reported. We compare the relaxation of the CuO/TiO2 surface under the electric fields in the direction of [001] or [010]. Fewer Cu-O bonds with highly coordinated Cu-ions are found in the CuO/TiO2 relaxed surface under the electric field in the [010] direction. The Cu-O bonds in the interface of the CuO/TiO2 surface led to an improved visible light absorption in the polarization direction of [001]. The CuO/TiO2 relaxed surface under the electric field in the [010] direction exhibits a more effective absorption of visible light. However, the electric field in the [001] direction induces more relaxation on the CuO/TiO2 surface, breaking the Cu-O bonds. This leads to the partial reduction of CuO to Cu2O on the CuO/TiO2 relaxed surface under the electric field in the [001] direction and inefficient absorption of visible light is observed for this surface.
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Long non-coding RNAs (lncRNAs) are series of transcripts with important biological functions. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. In this review, we highlight the mechanisms of dynamic lncRNA expression. The chromatin state contributes to the low and specific expression of lncRNAs. The transcription of non-coding RNA genes is regulated by many core transcription factors applied to protein-coding genes. However, specific DNA sequences may allow their unsynchronized transcription with their location-associated mRNAs. Additionally, there are multiple mechanisms involved in the post-transcriptional regulation of lncRNAs. Among these, microRNAs might have indispensible regulatory effects on lncRNAs, based on recent discoveries.
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Regulación de la Expresión Génica , ARN Largo no Codificante/genética , Animales , Humanos , Procesamiento Postranscripcional del ARN , Estabilidad del ARN , ARN Largo no Codificante/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Iniciación de la Transcripción GenéticaRESUMEN
Medical waste (MW) is exploding due to the COVID-19 pandemic, posing a significant environmental threat, and leading to the urgent requirement for affordable and environmentally friendly MW disposal technologies. Prior research on individual MW disposal plants is region-specific, applying these results to other regions may introduce bias. In this study, major MW disposal technologies in China, i.e., incineration technologies (pyrolysis incineration and rotary kiln incineration), and sterilization technologies (steam sterilization, microwave sterilization, and chemical disinfection) with residue landfill or incineration were analyzed from an industry-level perspective via life cycle assessment (LCA), life cycle costing (LCC) and net present value (NPV) methods. Life cycle inventories and economic cost data for 4-5 typical companies were selected from 128 distinct enterprises and academic sources for each technology. LCA results show that microwave sterilization with residue incineration has the lowest environmental impact, emitting only 480 kg CO2 eq. LCC and NPV analyses indicate that steam sterilization with landfilling is the most economical, yielding revenues of 1,210 CNY/t and breaking even in the first year. Conversely, pyrolysis and rotary kiln incineration break even between the 4th and 5th years. Greenhouse gas emissions from the MW disposal in ten cities with the largest MW production in 2020 increased by 7% over 2019 to 43,800 tons and other pollutants increased by 6% to 12%. Economically, Shanghai exhibits the highest cost-effectiveness, while Nanjing delivers the lowest. It can be observed that the adoption of optimal environmental technologies has resulted in a diminution of greenhouse gas emissions by 279,000 tons and energy conservation of 1.76 billion MJ.
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Gases de Efecto Invernadero , Eliminación de Residuos Sanitarios , Residuos Sanitarios , Eliminación de Residuos , Administración de Residuos , Humanos , Eliminación de Residuos Sanitarios/métodos , Ciudades , Vapor , Análisis Costo-Beneficio , Pandemias , China , Incineración/métodos , Instalaciones de Eliminación de Residuos , Eliminación de Residuos/métodos , Administración de Residuos/métodosRESUMEN
INTRODUCTION: A systematic review and meta-analysis were conducted to evaluate the efficacy and the overall safety of Faricimab compared with other anti-vascular endothelial growth factors (VEGF) therapy for neovascular age-related macular degeneration (AMD) and diabetic macular edema (DME). MATERIALS AND METHODS: A systematic literature search of a comprehensive electronic database was performed to identify randomized clinical trials published from January 2013 to January 2023 for Faricimab in AMD and DME. Weighted mean differences and risk ratios were used to integrate the different studies. RESULTS: A total of 4 randomized controlled trials (RCTs) with 1678 AMD patients and 3 RCTs with 20 DME patients were included in the meta-analysis.In patients with AMD, a significant difference was found in the number of injections between Faricimab and other anti-VEGF therapy (MDâ =â -2.42, 95% CI [-3.93 to -0.90], Pâ =â .002).No significant difference was found for the change in best corrected visual acuity (BVCA), central subfoveal thickness (CST), and gaining 15 or more letters. Similarly, no significant difference was found for adverse events.In patients with DME, a significant difference was observed for CST (MDâ =â -22.41, 95% CI [-29.95 to -14.86], Pâ <â .00001) and the number of injections(MDâ =â -0.93, 95% CI [-1.33 to -0.54], Pâ <â .00001). No significant difference was found for BVCA and gaining 15 or more letters, and no significant difference was found for adverse events. CONCLUSIONS: Comprehensive evidence confirms that Faricimab achieves non-inferior or even better CST improvement than other anti-VEGF therapies with extended dosing intervals, but more long-term follow-up studies are needed to support our conclusions.
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Anticuerpos Biespecíficos , Complicaciones de la Diabetes , Degeneración Macular , Edema Macular , Factor A de Crecimiento Endotelial Vascular , Anticuerpos Biespecíficos/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Degeneración Macular/terapia , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Edema Macular/etiología , Edema Macular/terapia , Complicaciones de la Diabetes/terapia , Resultado del TratamientoRESUMEN
Reed straw and electric furnace dust (EFD) waste were used to prepare magnetic Fe-C composite (EFD&C) by co-precipitation and high-temperature activation method to remove Cr(VI) from water. The magnetic EFD&C owned a large specific surface (536.61 m2/g) and a porous structure (micropores and mesopores), and had an efficient removal capacity for Cr(VI). Under conditions of pH (2), the addition amount of EFD&C (1 g/L), the adsorption time (760 min), and the temperature (45 °C), the maximum adsorption capacity reached 111.94 mg/g. The adsorption mechanism mainly attributed to chemical adsorption (redox), Cr(VI) reduced to Cr(III) by Fe(II) and Fe(0) (from Fe3O4 and Fe components in EFD) and surface functional groups of -OH, C = C, C-C and O-C = O (from biochar), and secondary attributed to physical adsorption, Cr(VI) and Cr(III) (from reduced Cr(VI)) adsorbed into the porous structure of EFD&C. This study provided a feasible solution for the preparation of adsorbents for adsorbing heavy metals from iron-containing metallurgical solid waste and biomass waste, which contributed to reducing the environmental pollution and lowering the cost of adsorbent preparation.
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Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Carbón Orgánico/química , Hierro/química , Cromo/química , Adsorción , Fenómenos MagnéticosRESUMEN
Alzheimer's disease (AD) is characterized by progressive cognitive decline, which is considered as the most common form of dementia in the elderly. Recently, it is suggested that impaired cerebrovascular function may precede the onset of AD. Claudin-5, which is the most enriched tight junction protein, has been reported to prevent the passage of damaging material at the blood-brain barrier. However, whether claudin-5 impacts AD has no direct evidence. We found a decrease level of claudin-5 in the hippocampus of AD and elder mice. And intravenous injection of claudin-5 improved learning and memory ability in these mice, while knockout of the protein led to impaired learning and memory and long-term potentiation in adult control mice. Furthermore, the effects of claudin-5 are mediated by suppressing inhibitory GABAergic neurotransmission. Our results suggest benefit effects of claudin-5 on learning and memory, which may provide a new treatment strategy for AD.
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Enfermedad de Alzheimer , Claudina-5/metabolismo , Disfunción Cognitiva , Enfermedad de Alzheimer/metabolismo , Animales , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/metabolismo , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Ratones , Ratones Transgénicos , Transmisión Sináptica , Ácido gamma-Aminobutírico/metabolismoRESUMEN
The vascular endothelial growth factor receptor 2 (VEGFR2) is considered to be a pivotal target for anti-tumor therapy against angiogenesis of non-small cell lung cancer (NSCLC). However, effective and low-toxicity targeted therapies to inhibit VEGFR2 are still lacking. Here, biRGD-siVEGFR2 conjugate comprising murine VEGFR2 siRNA and [cyclo(Arg-Gly-Asp-D-Phe-Lys)-Ahx]2-Glu-PEG-MAL (biRGD) peptide which selectively binds to integrin αvß3 receptors expressing on neovascularization endothelial cell was synthesized. The anti-tumor activity and renal toxicity of biRGD-siVEGFR2 or its combination therapy with low-dose apatinib were investigated on NSCLC xenografts. The immunogenicity of biRGD-siVEGFR2 was also evaluated in C57BL/6J mice. In vivo, intravenously injected biRGD-siVEGFR2 substantially inhibited NSCLC growth with a marked reduction of vessels and a down-regulation of VEGFR2 in tumor tissue. Furthermore, biRGD-siVEGFR2 in combination with low-dose apatinib achieved powerful anti-tumor effect with less nephrotoxicity compared with the regular dose of apatinib. Besides, no obvious immunogenicity of biRGD-siVEGFR2 was found. These findings demonstrate that biRGD-siVEGFR2 conjugate can be used as a new candidate for the treatment of NSCLC and its combination therapy with apatinib may also provide a novel strategy for cancer treatment in clinic.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Péptidos Cíclicos/farmacología , ARN Interferente Pequeño/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/metabolismo , Péptidos Cíclicos/administración & dosificación , Piridinas/farmacología , ARN Interferente Pequeño/administración & dosificación , Distribución Aleatoria , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The aim of this paper is to report the study on gene silencing efficiency of siRNA targeted against mouse VEGFR2 (siVEGFR2) in vitro mediated by polyethyleneimine (PEI) and its anti-tumor effect in vivo. CY3-labeled siRNA was compounded into PEI and transfected into MS1 cells. Confocal microscopy was used to image the subcellular distribution of siRNA in MS1 cells. Semi-quantitative RT-PCR and Western blotting were used to evaluate VEGFR2 gene silencing induced by siVEGFR2/PEI complexes. A tumor-bearing nude mice model was established to compare the anti-tumor effect after delivered by local and systemic routes. siVEGFR2/PEI complex-transfected cells exhibited much fluorescence in cytoplasm with no evidence of nuclear accumulation. The expression levels of VEGFR2 mRNA and protein in PEI-transfected cells were significantly down-regulated compared with that in blank group, the silencing efficiency were 28.2% and 23.6% respectively. The tumor sizes in mice intratumorally injected with siVEGFR2/PEI complexes (189.429 +/- 17.562 mm3) were reduced definitely compared to that in mice injected with siVEGFR2/PEI complexes via vein route (315.507 +/- 20.491 mm3), or to saline groups (365.844 +/- 20.713 mm3). The study demonstrated that PEI could effectively transfect siRNA into cells and silence the VEGFR2 gene expression. Intratumoral delivery is more suitable for non-targeted modified PEI/siRNA complexes to inhibit the tumor growth in vivo. The present data lay a solid foundation to further study on the gene silencing mechanism for PEI-medicated RNAi and its anti-tumor efficiency in vivo.
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Silenciador del Gen , Neoplasias Pulmonares/patología , Polietileneimina/química , ARN Interferente Pequeño/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Línea Celular Tumoral , Células Cultivadas , Células Endoteliales/citología , Células Endoteliales/metabolismo , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Desnudos , Trasplante de Neoplasias , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Bazo/citología , Transfección , Carga Tumoral , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genéticaRESUMEN
Radiotherapy is one of the standard treatments for glioma patients; however, its clinical efficacy is limited by radioresistance. We identified a mechanism of such resistance mediated by linc-RA1 (radioresistance-associated long intergenic noncoding RNA 1). Linc-RA1 was upregulated in radioresistant glioma cells and glioma tissue samples, compared with radiosensitive cells and nontumor tissues. Linc-RA1 was associated with inferior overall survival and advanced clinical stage of glioma. Linc-RA1 promoted glioma radioresistance in vitro and in vivo. Mechanistically, linc-RA1 stabilized the level of H2B K120 monoubiquitination (H2Bub1) by combining with H2B and inhibiting the interaction between H2Bub1 and ubiquitin-specific protease 44 (USP44), which inhibited autophagy, thus contributing to glioma radioresistance. These results reveal that linc-RA1-mediated autophagy is a key mechanism of radioresistance and is an actionable target for improving radiotherapy efficacy in patients with glioma.