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1.
Adv Sci (Weinh) ; 7(16): 2000925, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32832354

RESUMO

Metastasis accounts for 90% of cancer death worldwide, and effective therapeutic strategies are lacking. The aim of this work is to identify the key drivers in tumor metastasis and screen therapeutics for treatment of esophageal squamous cell carcinoma (ESCC). Gene Ontology analysis of The Cancer Genome Atlas (TCGA) gene expression datasets of ESCC patients with or without lympy metastasis identifies that TGFß2 is highly enriched in the pathways essential for tumor metastasis and upregulates in the metastatic ESCC tumors. High TGFß2 expression in ESCC correlates with metastasis and patient survival, and functionally contributes to tumor metastasis via activating extracellular signal-regulated kinases (ERK) signaling. By screening of a library consisting of 429 bioactive compounds, imperatorin is verified as a novel TGFß2 inhibitor, with robustly suppressive effect on tumor metastasis in multiple mice models. Mechanistically, direct binding of imperatorin and CREB1 inhibits phosphorylation, nuclear translocation of CREB1, and its interaction with TGFß2 promoter, represses TGFß2 expression and fibroblasts-secreted CCL2, and then inactivates ERK signaling to block cancer invasion and abrogates the paracrine effects of fibroblasts on tumor angiogenesis and metastasis. Overall, the findings suggest the use of TGFß2 as a diagnostic and prognostic biomarker and therapeutic target in ESCC, and supports the potential of imperatorin as a novel therapeutic strategy for cancer metastasis.

2.
Theranostics ; 9(6): 1599-1613, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31037126

RESUMO

Rationale: Dysregulated microRNA (miRNA) expressions in cancer can contribute to chemoresistance. This study aims to identify miRNAs that are associated with fluorouracil (5-FU) chemoresistance in esophageal squamous cell carcinoma (ESCC). The potential of miR-29c as a novel diagnostic, prognostic and treatment-predictive marker in ESCC, and its mechanisms and therapeutic implication in overcoming 5-FU chemoresistance were explored. Methods: The miRNA profiles of an ESCC cell model with acquired chemoresistance to 5-FU were analyzed using a Taqman miRNA microarray to identify novel miRNAs associated with 5-FU chemoresistance. Quantitative real-time PCR was used to determine miR-29c expression in tissue and serum samples of patients. Bioinformatics, gain- and loss-of-function experiments, and luciferase reporter assay were performed to validate F-box only protein 31 (FBXO31) as a direct target of miR-29c, and to identify potential transcription factor binding events that control miR-29c expression. The potential of systemic miR-29c oligonucleotide-based therapy in overcoming 5-FU chemoresistance was evaluated in tumor xenograft model. Results: MiR-29c, under the regulatory control of STAT5A, was frequently downregulated in tumor and serum samples of patients with ESCC, and the expression level was correlated with overall survival. Functional studies showed that miR-29c could override 5-FU chemoresistance in vitro and in vivo by directly interacting with the 3'UTR of FBXO31, leading to repression of FBXO31 expression and downstream activation of p38 MAPK. Systemically administered miR-29c dramatically improved response of 5-FU chemoresistant ESCC xenografts in vivo. Conclusions: MiR-29c modulates chemoresistance by interacting with FBXO31, and is a promising non-invasive biomarker and therapeutic target in ESCC.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/patologia , Proteínas F-Box/metabolismo , Fluoruracila/farmacologia , MicroRNAs/metabolismo , Neoplasias de Células Escamosas/patologia , Proteínas Supressoras de Tumor/metabolismo , Perfilação da Expressão Gênica , Humanos , Modelos Teóricos , Células Tumorais Cultivadas
3.
ISA Trans ; 84: 111-117, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30316571

RESUMO

The optimal modified performance of the multi-input multi-output (MIMO) networked control systems (NCSs) with encoding-decoding, channel noise in the forward channel and packet dropouts, quantization in the feedback channel is investigated in this paper. A new and efficient tracking performance index for the NCSs is presented which prevents variations in the tracking error where there is no integrator in the plant. The optimal modified performance is obtained by the method of coprime factorization and partial fraction. The results demonstrate that the optimal modified performance is related to the locations of the non-minimum phase (NMP) zeros, unstable poles of the given plant as well as their directions. In addition, the modified factor, packet dropouts probability, channel noise and encoding-decoding are also closely related to optimal modified performance of the NCSs. Finally, we present some particular examples to illustrate the theoretical results.

4.
Nanomaterials (Basel) ; 8(12)2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30551647

RESUMO

Due to their excellent properties and two-dimensional geometry, graphenes (Grs) have been widely used as reinforced fillers in graphene/aluminum nanolaminated composite (GANC). The separation and slippage behavior of the GANC is highly dependent on the interfacial properties between Gr and aluminum (Al). In this study, two interfacial failures of GANCs, i.e., pull-up failure and pull-out failure, were investigated using a molecular dynamics (MD) method. The effects of the crystal orientation of single-crystal Al component and the geometry of the Gr component on the normal and shear interfacial properties of the GANC were examined. It was evident that the interfacial pull-up resistance resulted from the atomic forces of all the atoms at the interface, whereas the interfacial shear force during pull-out stems from the atomic forces of the atoms at the crack tip. In addition, the studies revealed that the interface bonding strength between the Gr and Al was sensitive to both the crystal orientation of the Al and the environmental temperature. Finally, the cohesive law was used to describe the interfacial behavior of the Gr and Al, providing the interfacial data for the finite element modeling of composites with Gr and Al interface.

5.
J Agric Food Chem ; 66(35): 9248-9258, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30113849

RESUMO

A library consisting of 429 food-source compounds was used to screen the natural products with anticancer properties in esophageal squamous cell carcinoma (ESCC). We demonstrated for the first time that synephrine, an active compound isolated from leaves of citrus trees, markedly suppressed cell proliferation (inhibition rate with 20 µM synephrine at day 5:71.1 ± 5.8% and 75.7 ± 6.2% for KYSE30 and KYSE270, respectively) and colony formation (inhibition rate with 10 µM synephrine: 86.5 ± 5.9% and 82.3 ± 4.5% for KYSE30 and KYSE270, respectively), as well as migration (inhibition rate with 10 µM synephrine: 76.9 ± 4.4% and 62.2 ± 5.8% for KYSE30 and KYSE270, respectively) and invasion abilities (inhibition rate with 10 µM synephrine: 73.3 ± 7.5% and 75.3 ± 3.4% for KYSE30 and KYSE270, respectively) of ESCC cells in a dose-dependent manner, without significant toxic effect on normal esophageal epithelial cells. Mechanistically, quantitative proteomics and bioinformatics analyses were performed to explore the synephrine-regulated proteins. Western blot and qRT-PCR data indicated that synephrine may downregulate Galectin-3 to inactivate AKT and ERK pathways. In addition, we found that the sensitivity of ESCC to fluorouracil (5-FU) could be enhanced by synephrine. Furthermore, in vivo experiments showed that synephrine had significant antitumor effect on ESCC tumor xenografts in nude mice (inhibition rate with 20 mg/kg synephrine is 61.3 ± 20.5%) without observed side effects on the animals. Taken together, synephrine, a food-source natural product, may be a potential therapeutic strategy in ESCC.


Assuntos
Citrus/química , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/fisiopatologia , Sistema de Sinalização das MAP Quinases , Extratos Vegetais/administração & dosagem , Sinefrina/administração & dosagem , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Galectina 3/genética , Galectina 3/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Extratos Vegetais/química , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sinefrina/química
6.
J Chem Theory Comput ; 13(8): 3706-3714, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28682610

RESUMO

Graphene is a one-atom thick layer of carbon atoms arranged in a hexagonal pattern, which makes it the strongest material in the world. The Tersoff potential is a suitable potential for simulating the mechanical behavior of the complex covalently bonded system of graphene. In this paper, we describe a new coarse-grained (CG) potential, TersoffCG, which is based on the function form of the Tersoff potential. The TersoffCG applies to a CG model of graphene that uses the same hexagonal pattern as the atomistic model. The parameters of the TersoffCG potential are determined using structural feature and potential-energy fitting between the CG model and the atomic model. The modeling process of graphene is highly simplified using the present CG model as it avoids the necessity to define bonds/angles/dihedrals connectivity. What is more, the present CG model provides a new perspective of coarse-graining scheme for crystal structures of nanomaterials. The structural changes and mechanical properties of multilayer graphene were calculated using the new potential. Furthermore, a CG model of a graphene aerogel was built in a specific form of assembly. The chemical bonding in the joints of graphene-aerogel forms automatically during the energy relaxation process. The compressive and recover test of the graphene aerogel was reproduced to study its high elasticity. Our computational examples show that the TersoffCG potential can be used for simulations of graphene and its assemblies, which have many applications in areas of environmental protection, aerospace engineering, and others.

7.
Nanomaterials (Basel) ; 6(10)2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28335306

RESUMO

A nanorope is comprised of several carbon nanotubes (CNTs) with different chiralities. A molecular dynamic model is built to investigate the ionic adsorption and desorption of the CNT nanoropes. The charge distribution on the nanorope is obtained by using a modified gradient method based on classical electrostatic theory. The electrostatic interactions among charged carbon atoms are calculated by using the Coulomb law. It was found here that the charged nanorope can adsorb heavy metal ions, and the adsorption and desorption can be realized by controlling the strength of applied electric field. The distance between the ions and the nanorope as well as the amount of ions have an effect on the adsorption capacity of the nanorope. The desorption process takes less time than that of adsorption. The study indicates that the CNT nanorope can be used as a core element of devices for sewage treatment.

8.
Ying Yong Sheng Tai Xue Bao ; 24(9): 2599-607, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24417120

RESUMO

Taking the Dongguan City with rapid urbanization as a case, and selecting landscape ecological security level as evaluation criterion, the urbanization cellular number of 1 km x 1 km ecological security cells was obtained, and imbedded into the transition rules of cellular automata (CA) as the restraint term to control urban development, establish ecological security urban CA, and simulate ecological security urban development pattern. The results showed the integrated landscape ecological security index of the City decreased from 0.497 in 1998 to 0.395 in 2005, indicating that the ecological security at landscape scale was decreased. The CA-simulated integrated ecological security index of the City in 2005 was increased from the measured 0.395 to 0.479, showing that the simulated urban landscape ecological pressure from human became lesser, ecological security became better, and integrated landscape ecological security became higher. CA could be used as an effective tool in researching urban ecological security.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Modelos Teóricos , Urbanização , China , Cidades , Simulação por Computador , Ecologia/métodos
9.
Chin J Integr Med ; 12(2): 118-21, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16800990

RESUMO

OBJECTIVE: To investigate the effect of Chinese recipe, Wuye Decoction (WYD), on immune function in patients with non-small cell lung cancer (NSCLC). METHODS: Eighty-two patients of NSCLC with pathologically confirmed diagnosis, who had received operative treatment and completed the post-operational chemotherapy, were randomly assigned into 2 groups. Group A (42 cases) received WYD and Group B (40 cases) received no specific medicine. Positive rate of various peripheral lymphocyte subsets, including CD3, CD4, CD8, CD16, CD19 and CD25, in both groups was observed immediately after chemotherapy (T(0)) and 3 months later (T(1)), the same indexes of 20 healthy volunteers allocated in Group C were also determined at T(0) for control. RESULTS: The positive rates of CD4, CD4/CD8, CD16, CD19 and CD25 were significantly lower (P < 0.05) while that of CD8 was significantly higher (P < 0.05) in Group A and B at T(0) than those in Group C; at T(1), these indexes, except CD25, got significantly restored in Group A with the level approaching normal range (P > 0.05), and showed significant difference from those in Group B (P < 0.05), since these indexes in that group remained unchanged at the corresponding period. As for CD25, it was insignificantly changed in Group A after WYD treatment, and thus, at T(1), it was still lower than that in Group C (P < 0.05) and showed insignificant difference as compared with that in Group B (P > 0.05). Comparison of CD3 among the 3 groups showed no significant difference (P > 0.05). CONCLUSION: WYD could activate the immune function of NSCLC patients, and so it is recommended to be used in the treatment of NSCLC in clinical practice.


Assuntos
Adjuvantes Imunológicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/imunologia , Subpopulações de Linfócitos/imunologia , Adjuvantes Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fenótipo
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