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1.
Opt Lett ; 49(4): 818-821, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359190

RESUMO

Artificial neural networks usually consist of successive linear multiply-accumulate operations and nonlinear activation functions. However, most optical neural networks only achieve the linear operation in the optical domain, while the optical implementation of activation function remains challenging. Here we present an optical ReLU-like activation function (with 180° rotation) based on a semiconductor laser subject to the optical injection in an experiment. The ReLU-like function is achieved in a broad regime above the Hopf bifurcation of the injection-locking diagram and is operated in the continuous-wave mode. In particular, the slope of the activation function is reconfigurable by tuning the frequency difference between the master laser and the slave laser.

2.
Opt Express ; 31(2): 2456-2466, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785259

RESUMO

Time-delay reservoir computing uses a nonlinear node associated with a feedback loop to construct a large number of virtual neurons in the neural network. The clock cycle of the computing network is usually synchronous with the delay time of the feedback loop, which substantially constrains the flexibility of hardware implementations. This work shows an asynchronous reservoir computing network based on a semiconductor laser with an optical feedback loop, where the clock cycle (20 ns) is considerably different to the delay time (77 ns). The performance of this asynchronous network is experimentally investigated under various operation conditions. It is proved that the asynchronous reservoir computing shows highly competitive performance on the prediction task of Santa Fe chaotic time series, in comparison with the synchronous counterparts.

3.
Environ Sci Pollut Res Int ; 30(18): 51422-51439, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36809631

RESUMO

In recent years, environmental, social, and governance (ESG) have been extensive concerned. However, few studies have focused on the impact of situational factors on corporate ESG practice decisions. Based on this, using 9428 observations of Chinese A-share listed companies from 2009 to 2019, this paper attempts to explore the impact of local official turnover on corporate ESG practices, and analyzes the boundary effects of this impact from three aspects: region, industry, and corporate. Our results suggest that (1) official turnover can lead to changes in economic policies and redistribution of political resources, which can stimulate companies' "risk aversion motivation" and "development motivation" and thus promote their ESG practices; (2) this effect is more significant in the high degree of government intervention, the high level of industry competition and private corporates. (3) Further test finds that only when the official turnover abnormally and the regional economic development well, official turnover can significantly contribute to corporate ESG. This paper enriches the relevant research on the decision-making scenarios of corporate ESG practices from the macro-institutional perspective.


Assuntos
Tomada de Decisões Gerenciais , Meio Ambiente , Regulamentação Governamental , Corporações Profissionais , Fatores Socioeconômicos , China , Desenvolvimento Econômico , Governo , Motivação , Reorganização de Recursos Humanos , Corporações Profissionais/economia , Corporações Profissionais/organização & administração , Assunção de Riscos
4.
Anal Chem ; 94(32): 11298-11306, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35926081

RESUMO

Herein, a novel strategy was proposed for identifying carbon monoxide (CO), which plays a crucial part in living systems. For the first time, we have managed to design, synthesize, and characterize successfully this new Cu2+-assisted fluorescent probe (DPHP) in detecting CO. Compared with the commonly adopted Pd0-mediated Tsuji-Trost reaction recognition method, such a new strategy did not engage costly palladium (II) salt and generated no leaving group, indicating a satisfactory anti-interference ability. The recognition mechanism was confirmed by IR, 1H NMR titration, HR-MS, cyclic voltammetry, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and optical properties. Surprisingly, it was found that the new method achieved high selectivity and rapid identification of CO with a lower limit of detection (1.7 × 10-8 M). More intriguingly, it could recognize endogenous and exogenous CO in HeLa cells. The cytotoxicity of this new method was so low that it allowed the detection of CO in mice and zebrafish. Basically, our results trigger a novel viewpoint of rationally designing and synthesizing advanced materials for CO detection with unique features, impelling new research in detection chemistry.


Assuntos
Monóxido de Carbono , Corantes Fluorescentes , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Camundongos , Imagem Óptica/métodos , Peixe-Zebra
5.
J Colloid Interface Sci ; 628(Pt A): 308-317, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35932668

RESUMO

Molybdenum-based oxides have been widely investigated as promising material for lithium ion batteries owing to their unique physical and chemical properties as well as the large specific capacities. However, the fast capacity fading and poor cyclability originated from the large volume expansion and the sluggish electrode kinetics still inhibit their practical application. Herein, Ag nanoparticles combined with amorphous MoOx-in-plane nanoconfined on three dimensional N-doped porous carbon networks (3DNC) are designed and synthesized through salt-template strategy accompanied by annealing treatment and hydrothermal method (3DNC-MoOx-Ag). The synergistic effect of Ag nanoparticles and amorphous MoOx can inhibit the "dead volume" and aggregation of the electrode, accommodate the volume change, accelerate the diffusion kinetics during the lithium ion intercalation and de-intercalation processes. As a result, the designed 3DNC-MoOx-Ag delivers prominent cycling stability (834 mAh g-1 after 100 cycles at 200 mA g-1) and excellent rate performance (419 mAh g-1 after 70 cycles at 5000 mA g-1). Even at 5000 mA g-1, a specific capacity as high as 369 mAh g-1 can be achieved after 500 cycles.

6.
Angew Chem Int Ed Engl ; 61(30): e202205906, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35535865

RESUMO

Chiral hybrid metal halides with a high dissymmetry factor (glum ) and a superior photoluminescence quantum yield (PLQY) are promising candidates for circularly polarized luminescence (CPL) light sources. Here, we report eight new chiral hybrid manganese halides, crystallizing in the non-centrosymmetric space group P21 21 21 and showing intense CPL emissions. Oppositely-signed circular dichroism (CD) and CPL signals are detected according to the R- and S-configurations of the chiral alkanolammonium cations. Time-resolved PL spectra show long averaged decay lifetimes up to 1 ms for (R-3-quinuclidinol)MnBr3 (R-1). The glum of polycrystalline samples for coordinated structures (23×10-3 ) is more than doubled compared with the non-coordinated ones (8.5×10-3 ), due to the structural variations. R-1 exhibit both a high glum and a high PLQY (50.2 %). The effective chirality transfer mechanism through coordination bonds, with strongly emissive MnII centers, enables a new class of high-performance CPL materials.

7.
IEEE Trans Pattern Anal Mach Intell ; 43(7): 2257-2268, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33905326

RESUMO

We present a neural modeling framework for non-line-of-sight (NLOS) imaging. Previous solutions have sought to explicitly recover the 3D geometry (e.g., as point clouds) or voxel density (e.g., within a pre-defined volume) of the hidden scene. In contrast, inspired by the recent Neural Radiance Field (NeRF) approach, we use a multi-layer perceptron (MLP) to represent the neural transient field or NeTF. However, NeTF measures the transient over spherical wavefronts rather than the radiance along lines. We therefore formulate a spherical volume NeTF reconstruction pipeline, applicable to both confocal and non-confocal setups. Compared with NeRF, NeTF samples a much sparser set of viewpoints (scanning spots) and the sampling is highly uneven. We thus introduce a Monte Carlo technique to improve the robustness in the reconstruction. Experiments on synthetic and real datasets demonstrate NeTF achieves state-of-the-art performance and can provide reliable reconstructions even under semi-occlusions and on non-Lambertian materials.


Assuntos
Algoritmos , Redes Neurais de Computação , Imageamento Tridimensional , Método de Monte Carlo
8.
ACS Omega ; 6(12): 8616-8624, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33817522

RESUMO

A new fluorescent probe LXY based on the rhodamine 6G platforms has been designed, synthesized, and characterized, which could recognize Fe3+ effectively in HEPES buffer (10 mM, pH = 7.4)/CH3CN (2:3, v/v). And the distinct color change and the rapid emergence of fluorescence emission at 550 nm achieved "naked eye" detection of Fe3+. The interaction mode between them was achieved by Job's plot, MS, SEM, and X-ray single-crystal diffraction. Importantly, the crystal structures proved that Fe3+ could induce the rhodamine moiety transform the closed-cycle form to the open-cycle form. But it is interesting that Fe3+ did not appear in the crystal structures. Meanwhile, the limit of detection (LOD) of LXY to Fe3+ was calculated to be 3.47 × 10-9. In addition, the RGB experiment, test papers, and silica gel plates all indicated that the probe LXY could be used to distinguish Fe3+ quantitatively and qualitatively on-site. Moreover, the probe LXY has also been successfully applied to Fe3+ image in Caenorhabditis elegans, adult mice, and plant tissues. Thus, LXY was considered to have some potential for application in bioimaging.

9.
Onco Targets Ther ; 13: 12141-12149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33268993

RESUMO

PURPOSE: To determine the role and underlying mechanism of hepsin in epithelial-mesenchymal transition (EMT) and cell invasion in prostate cancer. METHODS: The expression of hepsin in prostate cancer tissue samples and cell lines was measured by immunohistochemical staining and Western blotting. The EMT and cell invasion abilities of prostate cancer cells were detected by Western blot and transwell assays. RNA transfection was used to inhibit or overexpress related genes. The expression of miR-222 was detected by RT-qPCR. A dual­luciferase reporter gene assay was performed to determine the target of miR-222. RESULTS: Hepsin expression was upregulated in prostate cancer tissue samples and cell lines. Inhibition of hepsin attenuated EMT and cell invasion and downregulated the expression of miR-222. Decreased miR-222 expression enhanced the level of PPP2R2A, which in turn attenuated the AKT signaling. Activation of miR-222 or AKT could block the inhibitory effects on EMT and cell invasion induced by hepsin deficiency. CONCLUSION: Hepsin promotes EMT and cell invasion through the miR-222/PPP2R2A/AKT axis in prostate cancer.

10.
Ther Adv Med Oncol ; 12: 1758835920970845, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240400

RESUMO

Urothelial carcinoma (UC) is a common malignancy of the lower and upper urinary tract. Recurrent UC has poor prognosis due to delayed diagnosis and a lack of clinical management guidance, especially for upper urinary tract UC. Patients with germline or somatic BRCA1/2 mutations are a special population in UC. No evidence is available so far on the effectiveness of poly ADP-ribose polymerase inhibitor (PARPi) in this population. Here, we report a 60-year-old female patient diagnosed with left ureter high-grade UC. Recurrent lesions were found 20 months after radical surgery. Computed tomography (CT) examination showed a slightly high-density soft tissue mass (3.2 × 3.1 cm) on the left posterior wall of the abdomen (waist), soft tissue mass adjacent to the left inner wall of the pelvis (3.2 × 4.2 cm), and multiple enlarged lymph nodes to the left of abdominal aorta. A next-generation sequencing (NGS)-based 605-gene panel detected a novel BRCA2 pathogenic germline mutation c.1670T>A (p.L557*), and a series of somatic insertion and deletion (INDEL) mutations of BRCA1, RB1, and JAK2, and single nucleotide variation (SNV) mutations of TP53, KMT2D, MET, ROS1, and IL7R. The above lesions were reduced significantly or disappeared (partial response, PR) after a 3-month Olaparib treatment, and the patient's general condition remained well. In conclusion, this study proved for the first time that PARPi was effective for UC treatment in patients carrying germline BRCA2 pathogenic mutations, providing new treatment options for such patients. In addition, the circulating tumor DNA (ctDNA) test can be used for drug selection and response monitoring in UC treatment.

11.
Front Chem ; 8: 800, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33134262

RESUMO

The fluorescent probe L, based on naphthalimide-modified coumarin, was designed, synthesized, and characterized, which could recognize Cu2+ from other cations selectively and sensitively in HEPES buffer (10 mM, Ph = 7. 4)/CH3CN (1:4, V/V). When the probe L interacted with Cu2+, the color and the fluorescent intensity changed obviously and it provided the naked-eye detection for Cu2+. The recognition mode between them was achieved by Job's plot, IR, MS, SEM, and 1HNMR. In addition, test strips made from L could still interact with Cu2+ in tap water effectively. The limit of detection (LOD) of L was 3.5 × 10-6 M. Additionally, the density functional theory (DFT) calculation method was used to analyze the action mechanism of L toward Cu2+. Importantly, the fluorescent probe L could demonstrate favorable selectivity toward Cu2+ in Caenorhabditis elegans. Thus, L was considered to have some potential for application in bioimaging.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32570750

RESUMO

Environmental regulations (ERs) that can stimulate technological innovation (TI) are the key to enabling a win-win strategy that benefits both economic development and environmental protection. This study seeks to analyze the impacts of ERs on TI. Previous literature highlighted that the black box of TI can be decomposed into technology investment and technology transformation, but empirical studies on such a decomposition have largely been ignored. Moreover, a detailed discussion of the links between ERs and the decomposed components of TI has not been conducted in developing countries such as China. Our study attempts to address these research gaps by (i) decomposing TI using a novel data envelopment analysis (DEA) procedure and further analyzing the impacts of ERs on the decomposed components of TI and (ii) applying this novel methodology to Chinese context. Accordingly, this study is conducted in two stages. First, a novel application of the slack-based measure Network DEA model is developed to uncover the black box of TI using Chinese data in order to estimate the overall efficiency of technological innovation (TIE) and to decompose it into the efficiency of technology investment (TVE) and the efficiency of technology transformation (TTE). Second, a random effect Tobit model is applied to (i) investigate both the linear and nonlinear impacts of ERs on TIE in all sectors and (ii) examine whether the impacts of ERs on TVE and TTE in different subprocesses are heterogeneous or not. Our results have showed the benefits of decomposing TI: while technology transformation in China closely follows the trend of TI, the trend of technology investment is somewhat different. The estimation results further indicate that the impacts of ERs on TIE are nonlinear. Besides, ERs have heterogeneous impacts on the decomposed components of TI. The impacts of ERs on TVE are nonlinear, whereas the impacts of ERs on TTE are statistically insignificant.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Econômico , Invenções , China , Regulamentação Governamental , Investimentos em Saúde
13.
BMC Urol ; 20(1): 57, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460817

RESUMO

BACKGROUND: Penile squamous cell carcinoma (PSCC) represents an important public health problem for developing countries. The major prognostic factors in PSCC are pathological subtype, perineural invasion, lymphovascular invasion, depth of invasion and grade, which are hard to obtain precisely before the operation. Besides, micro-metastases will be detected in about 30% of intermediate-risk patients with clinically non-palpable inguinal lymph nodes after inguinal lymph node dissection (ILND). It means approximately 70% of patients are unable to benefit from ILND who might suffered from the complications of surgery. We hope some biomarkers could be found which are able to predict the outcome before surgery and reflect the inguinal lymph nodes metastasis. METHODS: A total of 349 consecutive patients of penile cancer in Yunnan cancer hospital in China between October 2002 and December2017. Two hundred twenty-five was succeed to follow-up. The association between NLR, LMR, PLR, LDH and Overall survival (OS), progression free survival (PFS), inguinal lymph node (N stage) was analyzed with K-M analysis, univariable, multivariable logistic regression and Kendall's tau-b correlation coefficient. RESULTS: Multivariable analysis reveal that only PLR was significant independent factor which is associated with inferior OS and PFS; Age and LDH was associated with inferior OS; Lymph node and metastatic status remained significant for OS and PFS as NCCN and EAU Guidelines indicated; the tumor type, initial treatment and NLR LMR were not significant in predicting both OS and PFS. NLR, LMR and PLR were corresponded to N stage, while LDH was not associated with the N stage based on logistic regression model analysis. NLR, LMR and PLR were found weakly related to N stage through an application of Kendall's tau-b correlation coefficient. CONCLUSIONS: PLR was significant independent factors for OS and PFS, Age and LDH was significant independent factors for OS. NLR, LMR, PLR was corresponded to N stage.


Assuntos
Plaquetas , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/mortalidade , L-Lactato Desidrogenase/sangue , Linfócitos , Monócitos , Neutrófilos , Neoplasias Penianas/sangue , Neoplasias Penianas/mortalidade , Adulto , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
14.
Int Urol Nephrol ; 52(1): 187-196, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31828476

RESUMO

BACKGROUND: Cisplatin could result in a wide range of kidney injuries. During the pathogenetic process, the excessive generation of reactive oxygen species (ROS) induced by cisplatin has been regarded as the initial and critical role, by which DNA damage and cell death could subsequently come up. Therefore the elimination of ROS has long been considered as effective mean to prevent cisplatin-induced kidney injury. Myricitrin is a newfound natural polyphenol hydroxy flavonoid glycoside compound, whose forceful anti-oxidative properties had been confirmed. Thus, we aim to investigate if myricitrin could protect against cisplatin-induced kidney injury. METHODS: A cisplatin-induced kidney injury model was established in mice by intraperitoneal injection of cisplatin. The protective effect of myricitrin on kidney injury was evaluated by serum BUN and Cre level. The Kidney pathology was observed with H&E and TUNEL staining. Then cell viability and apoptosis rate were measured using MMT assay and flow cytometry to assess if myricitrin could protect KH-2 cells against cisplatin-induced injury. The intracellular ROS was detected by ROS fluorogenic probe and quantitatively analyzed by flow cytometry. Finally, the expression of Bcl-2 and Bax was investigated by western blotting to indicate the influence in apoptosis pathway. RESULTS: Myricitrin could significantly remit kidney injury induced by cisplatin and inhibit apoptosis of KH-2 cells. In mechanism, myricitrin could eliminate ROS and subsequently block activation of apoptosis pathway. CONCLUSION: Myricitrin protects against cisplatin-induced kidney injury by eliminating excessive ROS.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Flavonoides/uso terapêutico , Injúria Renal Aguda/patologia , Animais , Apoptose , Sobrevivência Celular , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio
15.
Polymers (Basel) ; 11(10)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561626

RESUMO

A series of pyrenyl-containing PDMAA copolymers were prepared by free radical copolymerization of dimethylacrylamide (DMAA) with pyrenebutanoyloxy ethyl methacrylate (PyBEMA). The structure of as-prepared copolymers was characterized by UV, FT-IR and 1H NMR spectroscopy. The effect of cyclodextrins (α-CD, ß-CD and γ-CD) on the thermosensitivity and fluorescence of the copolymers in aqueous solutions were investigated. It was found that the as-prepared copolymers exhibit lower critical solution temperature (LCST)-type thermosensitivity. Cloud point (Tcp) decreases with the increasing molar content of PyBEMA unit in the copolymers. Tcp of the copolymers increases after the CD is added from half molar to equivalent amount relative to pyrenyl moiety, and that further adding twice equivalent CD results in a slight decrease in Tcp. The copolymers exhibit a pyrene emission located at 377 nm and a broad excimer emission centered at 470 nm. The copolymers in water present a stronger excimer emission (Intensity IE) relative to monomer emission (Intensity IM) than that in ethanol. The IE/IM values decrease after the addition of equivalent α-CD, ß-CD and γ-CD into the copolymers in aqueous solution, respectively. The IE/IM values abruptly increase as the copolymers' concentration is over 0.2 mg/L whether in ethanol solution or aqueous solution with or without CD, from which can probably be inferred that intra-polymeric pyrene aggregates dominate for solution concentration below 0.2 mg/L and inter-polymeric pyrene aggregates dominate over 0.2 mg/L. Furthermore, the formation of the CD pseudopolyrotaxanes makes it possible to form pyrene aggregates. For high concentration of 5 g/L, the copolymers and their inclusion complexes completely exhibit an excimer emission. The IE values abruptly increased as the temperature went up to Tcp, which indicates that the IE values can be used to research phase separation of polymers.

16.
Oncol Lett ; 15(6): 9953-9958, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29844842

RESUMO

The present study aimed to understand the roles of hepcidin and iron metabolism in the onset of prostate cancer. The prostate cancer LNCap, PC3 and DU145 cell lines were transfected with small interfering RNA (siRNA) targeting hepcidin to knockdown hepcidin expression in LNCap, PC3 and DU145 cells. The expression levels of hepcidin in prostate cancer and normal prostate RWPE-1cells were detected by western blot analysis. Exogenous hepcidin was added into the hepcidin-silenced cell lines. Intracellular iron levels were detected using a fluorescence assay, and the proliferative and migratory capacities of cells were detected using the MTT and wound-healing assays, respectively. The apoptotic rate was measured using flow cytometry, and changes in the expression of the iron-export protein ferroportin on the cell membrane were detected by western blot analysis. Hepcidin expression in prostate cancer cells was significantly higher than that of normal prostate cells (P<0.05). Furthermore, the iron levels of hepcidin-silenced cells (hepcidin-ve groups) were significantly lower than those in the cells treated with exogenous hepcidin (hepcidin+ve groups) (P<0.05). The proliferative capacity of the hepcidin+ve cells significantly exceeded those of the hepcidin-ve groups (P<0.05) and increased over time. In the wound-healing assay, the number of hepcidin+ve cells present within the scratch sites increased compared with hepcidin-ve cells, indicating a higher migration rate. Additionally, the expression of ferroportin in the hepcidin-ve groups significantly exceeded that in the hepcidin+ve groups (P<0.05). Hepcidin is involved in the onset of prostate cancer, most likely by reducing ferroportin expression and increasing intracellular iron levels to enhance the proliferation, migration and anti-apoptotic capacities of cancer cells.

17.
RSC Adv ; 8(2): 895-903, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35538951

RESUMO

In this work, Co-P coatings were deposited from a chloride-based bath by direct current (DC), pulse current (PC) and pulse reverse current (PRC) methods, respectively. The effects of current modes on the microstructure, composition, microhardness, wear resistance and corrosion resistance of the Co-P coatings were explored. Results showed that the P content in the Co-P coatings increased and the surface roughness decreased in the sequence of DC, PC and PRC methods. The coatings with low P content deposited by DC and PC methods are crystalline with fcc and hcp structures, respectively, while the coating with high P content deposited by the PRC method is amorphous. Comparing to DC and PC methods, the PRC method can evidently improve the microhardness, wear resistance and corrosion resistance of Co-P coatings. The excellent wear and corrosion resistance of the Co-P coatings deposited by the PRC method could be attributed to its high P content, smooth surface and amorphous structure.

18.
Mol Cell Biochem ; 439(1-2): 95-104, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28795314

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs that exert their functions by targeting specific mRNA sequences. Many studies have demonstrated that miRNAs are crucial for cancer progression, during which they can act as either oncogenes or tumor suppressors. Previous research has shown that miR-335 is downregulated in breast cancer, and it has been shown to be a breast cancer suppressor. In addition, emerging evidence indicates that erythropoietin-producing hepatocellular A4 (EphA4) is implicated in cancer cell proliferation, migration, and invasion. However, little is known about the relationship between miR-335 and EphA4 in breast cancer. In the present study, we used bioinformatic and biochemical analyses to demonstrate that EphA4 is a direct downstream target of miR-335 in human breast cancer MCF-7 and MDA-MB-23 cells and revealed that miR-335 negatively regulates the expression of EphA4 in these cells. Further investigation revealed that miR-335 overexpression inhibits MCF-7 and MDA-MB-231 cell proliferation and that this inhibition is attenuated by EphA4 coexpression. Similarly, miR-335 overexpression also inhibited growth and downregulated EphA4 expression in tumors in nude mice. Moreover, our results demonstrated that miR-335 overexpression suppresses migration and invasion in MCF-7 and MDA-MB-231 cells, an effect that was reversed by EphA4 overexpression. These findings confirmed that EphA4 is a direct target gene of miR-335 and that miR-335 suppresses breast cancer cell proliferation and motility in part by directly inhibiting EphA4 expression.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Proliferação de Células , MicroRNAs/metabolismo , Proteínas de Neoplasias/biossíntese , RNA Neoplásico/metabolismo , Receptor EphA4/biossíntese , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Proteínas de Neoplasias/genética , RNA Neoplásico/genética , Receptor EphA4/genética
19.
Cancer Biomark ; 21(3): 613-620, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29278879

RESUMO

Long non-coding RNAs (lncRNAs) were playing critical roles in tumorigenesis. However, in prostate cancer, the roles and mechanisms of lncRNAs especially ANRIL were largely unknown. We investigated the effects of ANRIL on the proliferation and migration of prostate cancer cells using CCK-8 assay and Transwell migration assay. Real-time PCR and western blotting assays were used to analyze the levels of ANRIL, let-7a, TGF-ß1, p-Smad2 and p-Smad7. Our results showed that ANRIL was significantly overexpressed in prostate cancer tissues compared with corresponding normal tissues. Knockdown of ANRIL significantly inhibited the proliferation and migration of prostate cancer LNCap, PC3 and DU145 cells. Knockdown of ANRIL significantly decreased the levels of TGF-ß1 and p-Smad2, and increased the level of p-Smad7 in prostate cancer LNCap cells. We further found that knockdown of ANRIL significantly enhanced the expression of let-7a, and rescue experiment found that let-7a inhibitor recovered the suppressive effects of ANRIL silencing on the proliferation and migration of prostate cancer LNCap, PC3 and DU145 cells. And let-7a inhibitor recovered the suppressive effects of ANRIL silencing on the activity of TGF-ß1/Smad signaling pathway in prostate cancer LNCap cells. Taken together, our findings indicated that overexpression of lncRNA ANRIL promoted the proliferation and migration of prostate cancer cells via regulating let-7a/TGF-ß1/Smad signaling pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , Masculino , Neoplasias da Próstata/patologia
20.
Oncol Lett ; 14(6): 7970-7976, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29250185

RESUMO

Ectopic activation of the canonical Hedgehog signaling pathway is involved in the development and progression of prostate cancer, which is one of the leading causes of cancer-associated mortality in males worldwide. However, the role of the non-canonical Hedgehog signaling pathway in prostate cancer remains generally unexplored. In the present study, it was identified that Gli (glioma-associated oncogene)1 and Gli2 were highly expressed at the protein level in the androgen-independent prostate cancer cell lines PC3 and DU145, but not in the androgen-dependent cancer cell line LNCaP. Silencing of Gli1 using small interfering RNA markedly decreased PC3 cell viability and liquid colony formation in vitro. The Gli1/2-specific inhibitor GANT61 markedly decreased cell viability by inducing cell apoptosis in PC3 and DU145 cells. GANT61 also alleviated liquid colony formation efficiency in PC3 and DU145 cells, suggesting that the activity of Gli1 is required for prostate cancer cell survival. To explore further the upstream signaling pathway involved in the regulation of Gli1 expression, it was identified that tumor necrosis factor α-triggered mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase 1 (S6K1) activation was required for Gli1 expression. Pharmacological and genetic inhibition of S6K1 activation markedly decreased Gli1 and its downstream target gene mRNA expression. In addition, the phosphoinositide 3-kinase/mTOR inhibitor BEZ235 markedly decreased in vitro PC3 cell proliferation. The results of the present study indicate that the non-canonical Hedgehog pathway (mTOR/S6K1/Gli1) contributes to the development and progression of prostate cancer and that Gli1 is a potential therapeutic target in the treatment of prostate cancer.

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