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1.
Cancer Cell Int ; 24(1): 114, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528618

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of digestive system tumor related death in the world. Unfortunately, effective chemopreventive agent is lack for patients with ESCC in clinical practice, which leads to the extremely high mortality rate. METHODS: A library of prescribed drugs was screened for finding critical anti-tumor properties in ESCC cells. The phosphoproteomics, kinase array, pulldown assay and drug affinity responsive target stabilization assay (DARTS) were applied to explore mechanisms and searched for synergistic targets. Established models of PDX in mice were used to determine the therapeutic effect of domperidone. RESULTS: After screening a library of prescribed drugs, we discovered that domperidone has anti-tumor properties. Domperidone, acting as a gastroprokinetic agent, has been widely used in clinic for gastrointestinal motility disorders. Despite limited research, there are indications that domperidone may have anti-tumor properties. In this study, we determined that domperidone significantly inhibited ESCC proliferation in vitro and in vivo. We employed phosphoproteomics to reveal p-ERK, and p-SMAD3 down-regulation upon domperidone treatment. Then, the results of kinase assay and pulldown assay further validated that domperidone directly combined with MEK1/2 and CDK4, leading to the inhibition of their kinase activity. Furthermore, our results revealed that MEK/ERK and CDK4/SMAD3 signal pathway were major pathways in domperidone against ESCC. CONCLUSION: Collectively, these findings suggest that domperidone serves as an effective "multi-target" inhibitor of MEK1/2 and CDK4, offering potential benefits for the chemoprevention of ESCC.

2.
Mol Carcinog ; 62(4): 517-531, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36645220

RESUMO

Esophageal squamous cell carcinoma (ESCC) accounts for 90% of esophageal cancers and has a high mortality rate worldwide. The 5-year survival rate of ESCC patients in developing countries is <20%. Hence, there is an urgent need for developing new and effective treatments that are based on newly-discovered emerging molecules and pathways to prevent ESCC occurrence and recurrence. We investigated the effects of Daurisoline, a bis-benzylisoquinoline alkaloid extracted from the rhizome of menisperum dauricum, on ESCC cell proliferation and elucidated the molecular mechanisms underlying its functions. To explore the effects of Daurisoline on ESCC growth in vitro and in vivo, cell proliferation assays and anchorage-independent growth assays were performed and a patient-derived xenograft (PDX) model was established. Subsequently, phosphoproteomics, molecular docking analysis, pull down assays, mutation experiments and in vitro kinase assay were performed to explore the mechanism of Daurisoline's function on ESCC. Daurisoline inhibited ESCC proliferation in vitro and reduced ESCC PDX exnograft growth in vivo by reducing ERK1/2 phosphorylation. Furthermore, it directly bound to MEK1 (at Asn78 and Lys97) and MEK2 (at Asp194 and Asp212) kinases to inactivate the ERK1/2 signaling pathway. Our results suggest that Daurisoline is a dual inhibitor of MEK1 and MEK2 and suppresses ESCC growth both in vitro and in vivo by inactivating the ERK1/2 signaling pathway. This is first report on the use of MEK inhibitor for ESCC and highlights its potential applications for ESCC treatment and prevention.


Assuntos
Benzilisoquinolinas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Simulação de Acoplamento Molecular , Proliferação de Células , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Benzilisoquinolinas/farmacologia , Regulação Neoplásica da Expressão Gênica
3.
Opt Lett ; 48(4): 1052-1055, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791008

RESUMO

We demonstrate high-power longwave mid-IR ultrafast sources based on a high-power Er-fiber laser system at 1.55 µm with a 32-MHz repetition rate. Compared with previous 1.03-µm-driven difference frequency generation (DFG), our current configuration allows tighter focusing in the GaSe crystal thanks to an increased damage threshold at 1.55 µm. Consequently, the 1.55-µm-driven DFG can operate in the regime of optical parametric amplification (OPA), in which the mid-IR power grows exponentially with respect to the square root of the pumping power. We experimentally demonstrate this operation regime and achieve broadband mid-IR pulses that are tunable in the 7.7-17.3 µm range with a maximum average power of 58.3 mW, which is also confirmed by our numerical simulation.

4.
Br J Cancer ; 126(7): 1037-1046, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34912075

RESUMO

BACKGROUND: Due to the high recurrence and low 5-year survival rates of esophageal squamous cell carcinoma (ESCC) after treatment, the discovery of novel drugs for recurrence chemoprevention is of particular importance. METHODS: We screened the FDA-approved drug library and found that Nuplazid, an atypical antipsychotic that acts as an effective 5-HT 2 A receptor inverse agonist, could potentially exert anticancer effects in vitro and in vivo on ESCC. RESULTS: Pull-down results indicated that Nuplazid binds with p21-activated kinase 4 (PAK4), and a kinase assay showed that Nuplazid strongly suppressed PAK4 kinase activity. Moreover, Nuplazid exhibited inhibitory effects on ESCC in vivo. CONCLUSIONS: Our findings indicate that Nuplazid can suppress ESCC progression through targeting PAK4.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Piperidinas , Ureia/análogos & derivados , Quinases Ativadas por p21/metabolismo
5.
Anal Chem ; 94(49): 17212-17222, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36459499

RESUMO

Esophageal cancer, especially esophageal squamous cell carcinoma (ESCC), poses a serious threat to human health. It is urgently needed to develop recognition tools and discover molecular targets for early diagnosis and targeted therapy of esophageal cancer. Here, we developed several DNA aptamers that can bind to ESCC KYSE410 cells with a nanomolar range of dissociation constants by using cell-based systematic evolution of ligands by exponential enrichment (cell-SELEX). The selected A2 aptamer is found to strongly bind with multiple cancer cells, including several ESCC cell lines. Tissue imaging displayed that the A2 aptamer can specifically recognize clinical ESCC tissues but not the adjacent tissues. Moreover, we identified integrin ß1 as the binding target of A2 through pull-down and RNA interference assays. Meanwhile, molecular docking and mutation assays suggested that A2 probably binds to integrin ß1 through the nucleotides of DA16-DG21, and competitive binding and structural alignment assays indicated that A2 shares the overlapped binding sites with laminin and arginine-glycine-aspartate ligands. Furthermore, we engineered A2-induced targeted therapy for ESCC. By constructing A2-tethered DNA nanoassemblies carrying multiple doxorubicin (Dox) molecules as antitumor agents, inhibition of tumor cell growth in vitro and in vivo was achieved. This work provides a useful targeting tool and a potential molecular target for cancer diagnosis and targeted therapy and is helpful for understanding the integrin mechanism and developing integrin inhibitors.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Aptâmeros de Nucleotídeos/química , Integrina beta1/metabolismo , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/tratamento farmacológico , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Ligantes , Técnica de Seleção de Aptâmeros
6.
Sensors (Basel) ; 22(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36501890

RESUMO

The transmission of satellite payload data is critical for services provided by aerospace ground networks. To ensure the correctness of data transmission, the TCP data transmission protocol has been used typically. However, the standard TCP congestion control algorithm is incompatible with networks with a long time delay and a large bandwidth, resulting in low throughput and resource waste. This article compares recent studies on TCP-based acceleration algorithms and proposes an acceleration algorithm based on the learning of historical characteristics, such as end-to-end delay and its variation characteristics, the arrival interval of feedback packets (ACK) at the receiving end and its variation characteristics, the degree of data packet reversal and its variation characteristics, delay and jitter caused by the security equipment's deep data inspection, and random packet loss caused by various factors. The proposed algorithm is evaluated and compared with the TCP congestion control algorithms under both laboratory and ground network conditions. Experimental results indicate that the proposed acceleration algorithm is efficient and can significantly increase throughput. Therefore, it has a promising application prospect in high-speed data transmission in aerospace-ground service networks.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Retroalimentação , Aceleração
7.
J Cell Mol Med ; 25(4): 2176-2189, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33354912

RESUMO

Circulating exosomes delivering microRNAs are involved in the occurrence and development of cardiovascular diseases. How are the circulating exosomes involved in the repair of endothelial injury in acute myocardial infarction (AMI) convalescence (3-7 days) was still not clear. In this study, circulating exosomes from AMI patients (AMI-Exo) and healthy controls (Normal-Exo) were extracted. In vitro and in vivo, our study showed that circulating exosomes protected endothelial cells (HUVECs) from oxidative stress damage; meanwhile, Normal-Exo showed better protective effects. Through the application of related inhibitors, we found that circulating exosomes shuttled between HUVECs via dynamin. Microarry analysis and qRT-PCR of circulating exosomes showed higher expression of miR-193a-5p in Normal-Exo. Our study showed that miR-193a-5p was the key factor on protecting endothelial cells in vitro and in vivo. Bioinformatics analyses found that activin A receptor type I (ACVR1) was the potential downstream target of miR-193a-5p, which was confirmed by ACVR1 expression and dual-luciferase report. Inhibitor of ACVR1 showed similar protective effects as miR-193a-5p. While overexpression of ACVR1 could attenuate protective effects of miR-193a-5p. To sum up, these findings suggest that circulating exosomes could shuttle between cells through dynamin and deliver miR-193a-5p to protect endothelial cells from oxidative stress damage via ACVR1.


Assuntos
Células Endoteliais/metabolismo , Exossomos/metabolismo , Técnicas de Transferência de Genes , MicroRNAs/metabolismo , Adulto , Animais , Transporte Biológico , Biópsia , Biologia Computacional , Dinaminas/metabolismo , Exossomos/ultraestrutura , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Imuno-Histoquímica , Masculino , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/administração & dosagem , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Estresse Oxidativo , Plasmídeos , Interferência de RNA , Ratos
8.
Analyst ; 146(13): 4180-4187, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34105524

RESUMO

Esophageal cancer is the ninth most common cancer and the sixth most common cause of cancer-related death worldwide, and the esophageal squamous cell carcinoma (ESCC) subtype accounts for about 90% of all cases of esophageal cancer globally. Currently, ESCC is usually diagnosed in late stages, and targeted therapy is lacking. Therefore, the development of ESCC-specific recognition molecules for an early detection and targeted treatment of ESCC is urgently needed. Aptamers are an excellent molecular recognition tool with unique advantages. In this manuscript, three aptamers (S2, S3, and S8) specific to ESCC cells were successfully screened via cell-SELEX. The experimental results displayed the high affinities of the three aptamers for target KYSE150 cells with dissociation constants in the nanomolar range. The specificity evaluation showed that S2 only bound target KYSE150 cells, but S3 and S8 were capable of targeting a series of ESCC cells. Moreover, several truncated aptamers were generated through sequence optimization. In particular, an ultrashort aptamer S3-2-3 with only 18 bases was successfully obtained; after labeling with Cy5 dyes, it was feasible for the specific imaging of ESCC tissues. Furthermore, the target types of the selected aptamers were preliminarily identified as membrane proteins, and target proteins could be captured by S3-2-3, which may be useful for biomarker discovery. Therefore, the selected aptamers hold great potential for clinical diagnosis, biomarker discovery, and the targeted therapy of ESCC.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Linhagem Celular Tumoral , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Humanos , Técnica de Seleção de Aptâmeros
9.
Mol Carcinog ; 59(2): 215-226, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793679

RESUMO

The high incidence and mortality of esophageal squamous cell cancer (ESCC) is a major health problem worldwide. Precancerous lesions of ESCC may either progress to cancer or revert to normal epithelium with appropriate interventions; the bidirectional instability of the precancerous lesions of ESCC provides opportunities for intervention. Reports suggest that the upregulation of ornithine decarboxylase (ODC) is closely related to carcinogenesis. In this study, we investigated whether ODC may act as a target for chemoprevention in ESCC. Immunohistochemistry (IHC) assays indicate that ODC expression is higher in esophageal precancerous lesions compared with normal tissue controls. Its overexpression promotes cell proliferation and transformation of normal esophageal epithelial cells, and its activity is increased after N-nitrosomethylbenzylamine (NMBA) induction in Shantou human embryonic esophageal cell line (SHEE) and human immortalized cells (Het1A) cells. In addition, p38 α, extracellular regulated kinase (ERK1/2) in the mitogen-activated protein kinase pathway and protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K) pathways are activated in response to NMBA treatment. Difluoromethylornithine (DFMO) is an ODC inhibitor, which inhibits NMBA-induced activation of p38 α, ERK1/2 and AKT/mTOR/p70S6K pathways; this has been verified by Western blotting. DFMO was also found to suppress the development of esophageal precancerous lesions in an NMBA-induced rat model; IHC demonstrated p38 α, ERK1/2, and AKT/mTOR/p70S6K pathways to be downregulated in these rats. These findings indicate the mechanisms by which ODC inhibition suppresses the development of esophageal precancerous lesions by downregulating p38 α, ERK1/2, and AKT/mTOR/p70S6k signaling pathways, ODC may be a potential target for chemoprevention in ESCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Inibidores da Ornitina Descarboxilase/farmacologia , Ornitina Descarboxilase/metabolismo , Lesões Pré-Cancerosas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinógenos/farmacologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Dimetilnitrosamina/análogos & derivados , Dimetilnitrosamina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Humanos , Ornitina Descarboxilase/genética , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Transdução de Sinais/genética
10.
Mol Carcinog ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33289209

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors of the digestive tract in humans. Several studies have indicated that PAK4 is associated with the risk of ESCC and may be a potential druggable kinase for ESCC treatment. However, the underlying mechanism remains largely unknown. The aim of our study is to identify the functional role of PAK4 in ESCC. To determine the expression of PAK4 in ESCC, Western blot analysis and immunohistochemistry were performed, and the results showed that PAK4 is significantly upregulated in ESCC tissues and cell lines compared with normal controls and normal esophageal epithelial cell line. To further investigate the role of PAK4 in ESCC, cell viability assays, anchorage-independent cell growth assays, wound healing assays, cellular invasion assays, in vivo xenograft mouse models, and metastasis assays were conducted, and the results showed that PAK4 can significantly facilitate ESCC proliferation and metastasis in vitro and in vivo. To determine the potential target of PAK4 in ESCC progression, a pull-down assay was performed, and the results showed that LASP1 may be a potential target of PAK4. An immunoprecipitation assay and confocal microscopy analysis confirmed that PAK4 can bind to and colocalize with LASP1 in vitro and in cells. Notably, rescue experiments further illustrated the mechanistic network of PAK4/LASP1. Our research reveals the oncogenic roles of PAK4 in ESCC and preliminarily elucidates the mechanistic network of PAK4/LASP1 in ESCC.

11.
Opt Express ; 28(11): 15855-15862, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32549421

RESUMO

We use an ultrafast optical pump-probe spectroscopy to study quasiparticle (QP) dynamics in a topological insulator LaBi. Temperature-dependent optical measurements have been carried out, by which we observed nearly constant fast component (with a lifetime of 0.15 ps) and slow component (with a lifetime of 1.5 ps) for the whole range from 10 K to 295 K. The laser fluence dependence result shows that there is no saturation for the QP dynamics up to 3.3 mJ /cm2. Moreover, an Eg mode transverse optical (TO) coherent phonon has also been observed, with a frequency of 2.8 THz. Our results provide for the first time the ultrafast dynamics information of both the QPs and coherent phonons in a nodal line topological material.

12.
BMC Cancer ; 20(1): 43, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959146

RESUMO

Following publication of the original article [1], the authors reported the errors in Fig. 1C and D, Fig. 2, Fig. 4B and C and Fig. 6D and E.

13.
Analyst ; 145(7): 2676-2681, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32065595

RESUMO

Highly sensitive and specific detection of rare tumor cells is urgently needed for early tumor diagnosis. Herein, a split aptamer-based dual hybridization chain reaction (dual-HCR) strategy with flow cytometry analysis was developed to meet this purpose. With the split aptamer pair as the recognition unit and HCR as the signal amplification technique, this strategy achieved an improved detection limit as low as 20 cells in 200 µL binding buffer. Meanwhile, this method was highly specific with distinct recognition of the target cells from the control cell and mixed cell samples. Furthermore, we succeeded in the specific detection of the target cells in 50% human serum, demonstrating that this method has great potential in clinical applications. In theory, this strategy can be used to detect different target cells by using different split aptamers. Therefore, this general, sensitive and specific tumor cell detection method may be helpful for early clinical diagnosis and cancer research.


Assuntos
Aptâmeros de Nucleotídeos/química , Neoplasias/patologia , Hibridização de Ácido Nucleico/métodos , Aptâmeros de Nucleotídeos/metabolismo , Linhagem Celular Tumoral , Citometria de Fluxo , Corantes Fluorescentes/química , Humanos , Microscopia Confocal , Nanoestruturas/química , Neoplasias/diagnóstico , Neoplasias/metabolismo , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo
14.
Opt Lett ; 44(21): 5214-5217, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674971

RESUMO

We report on an unambiguous observation of the third-order nonlinear optical effect, spatial self-phase modulation (SSPM), in a MoTe2 dispersion. The values of the third-order nonlinear optical coefficients effectively for one-layer MoTe2, χone-layer(3), are obtained through the SSPM method at excitation wavelengths 473, 532, 750, and 801 nm, respectively. The wind-chime model is used to explain the ring formation time. The wavelength dependence of χone-layer(3) compares well with the photo-absorption spectra. Significantly, we find a correlation between χ(3) and the carrier mobility µ or effective mass m*, which again further supports the laser-induced ac electron coherence in 2D materials.

15.
BMC Cancer ; 19(1): 1264, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888532

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a fatal disease with poor prognosis. The predominant reason for ESCC-related death is distal metastasis. A comprehensive understanding of the molecular mechanism underlying metastasis is needed for improving patient prognosis. T-LAK cell-originated protein kinase (TOPK) is a MAPKK-like kinase, which plays a vital role in various physiological and pathophysiological processes. However, the role of TOPK in ESCC metastasis is unclear. METHODS: Tissue array was used to evaluate the correlation between TOPK expression and ESCC lymph node metastasis. Wound healing assay, transwell assay, and lung metastasis mice model were used to examine the role of TOPK in the migration of ESCC cells in vitro and in vivo. Protein kinase array, mass spectrometry (MS), and molecular modeling were used to examine the pathways and direct target proteins of TOPK that are involved in ESCC metastasis. Additionally, immunofluorescence and western blotting analyses were performed to verify these findings. RESULTS: The enhanced expression of TOPK was correlated with lymph node metastasis in the ESCC tissues. TOPK knockdown or treatment with the TOPK inhibitor (HI-TOPK-032) decreased the invasion and migration of ESCC cells in vitro. HI-TOPK-032 also inhibited the lung metastasis in ESCC cell xenograft in vivo model. Moreover, TOPK promoted the invasion of ESCC cells by activating the Src/GSK3ß/STAT3 and ERK signaling pathways via γ-catenin. CONCLUSION: The findings of this study reveal that TOPK is involved in ESCC metastasis and promoted the ESCC cell mobility by activating the Src/GSK3ß/STAT3 and ERK signaling pathways. This indicated that TOPK may be a potential molecular therapeutic target for ESCC metastasis.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , gama Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Glicogênio Sintase Quinase 3 beta/metabolismo , Xenoenxertos , Humanos , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Invasividade Neoplásica , Estadiamento de Neoplasias , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Quinases da Família src/metabolismo
16.
Mol Carcinog ; 57(11): 1540-1552, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30035335

RESUMO

Esophageal squamous cell carcinoma (ESCC) is highly prevalent in Asia, especially in China. Research findings indicate that nitrosamines, malnutrition, unhealthy living habits, and genetics contribute to esophageal carcinogenesis. Currently, the 5-year survival rate for ESCC patients remains low, owing in part to a lack of a clear understanding of mechanisms involved. Chemoprevention using natural or synthesized compounds might be a promising strategy to reduce esophageal cancer incidence. The epidermal growth factor receptor (EGFR) can activate downstream pathways including the phosphatidylinositol 3-kinase (PI3K) pathway and the Ras/mitogen-activated protein kinase (MAPK) pathways. Among the important players, AKT and ERKs have an important relationship with cancer initiation and progression. Here, we found that phosphorylated (p)-AKT and p-ERKs were highly expressed in esophageal cancer cell lines and in esophageal cancer patients. Human phospho-kinase array and pull-down assay results showed that quercetin-3-methyl ether (Q3ME) is a natural flavonoid compound that interacted with AKT and ERKs and inhibited their kinase activities. At the cellular level, Q3ME attenuated esophageal cancer cell proliferation and anchorage-independent growth. Western blot analysis showed that this compound suppressed the activation of AKT and ERKs downstream signaling pathways, subsequently inhibiting activating protein-1 (AP-1) activity. Importantly, Q3ME inhibited the formation of esophageal preneoplastic lesions induced by N-nitrosomethylbenzylamine (NMBA). The inhibition by Q3ME was associated with decreased inflammation and esophageal cancer cell proliferation in vivo. Collectively, our data suggest that Q3ME is a promising chemopreventive agent against esophageal carcinogenesis by targeting AKT and ERKs.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Neoplasias Esofágicas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quercetina/análogos & derivados , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Biomarcadores , Linhagem Celular Tumoral , Mucosa Esofágica/metabolismo , Neoplasias Esofágicas/patologia , Humanos , Inflamação/metabolismo , Proteínas Quinases Ativadas por Mitógeno/química , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt/química , Quercetina/química , Quercetina/farmacologia , Ratos , Proteínas Quinases S6 Ribossômicas 70-kDa/química , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/química
17.
J Transl Med ; 16(1): 138, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29788985

RESUMO

BACKGROUND: The overall 5-year survival rate of lung cancer is about 15% even with therapeutic drugs like tyrosine kinase inhibitors. Ideal models are urgently needed for exploring mechanisms and finding new drugs. Patient-derived xenografts (PDX) models and primary cells are both used to screen therapeutic regimens for cancer. However, PDX models and primary cells from the same patient are difficult to establish. Their consistency to the original tumor tissue is not well studied. METHODS: 31 lung cancer patient tissues were procured to establish the lung cancer PDX models and primary cell lines. Tumor growth measurements, histological and immunohistochemistry analysis, Western blotting, EGFR and K-RAS mutation detection and gefitinib sensitive assay were performed to evaluate the characteristic of established PDX models. Immunofluorescence analysis, anchorage-independent cell growth, Western blotting and gefitinib sensitive assay were performed to assay the characteristic of established primary cell lines. The whole-exome sequencing was used to compare the characteristic of the patient's tumor tissue, established PDX and primary cell line. RESULTS: Twenty-one lung cancer PDX models (67.74%, 21/31) and ten primary cell lines (32.25%, 10/31) were established from patients' tumor tissues. The histology and pathological immunohistochemistry of PDX xenografts are consistent with the patients' tumor samples. Various signal pathways were activated in different PDX models (n = 5) and primary cell lines (n = 2). EGFR mutation PDX model and primary cell line (LG1) were sensitive to gefitinib treatment. The expression of CK8/18, TTF1 and NapsinA in LG1 and LG50 primary cells were also positive. And the activated signal pathways were activated in LG1 and LG50 primary cell lines. Furthermore, the gene mutation in PDX tumor tissues and primary cell line (LG50) was consistent with the mutation in LG50 patient's tumor tissues. CONCLUSION: These data suggested that established lung cancer PDX models and primary cell lines reserved mostly molecular characteristics of primary lung cancer and could provide a new tool to further understand the mechanisms and explore new therapeutic strategies.


Assuntos
Neoplasias Pulmonares/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Receptores ErbB/metabolismo , Feminino , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Camundongos Endogâmicos C57BL , Camundongos SCID , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos , Sequenciamento do Exoma
18.
Proc Natl Acad Sci U S A ; 112(38): 11800-5, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26351696

RESUMO

Generating electron coherence in quantum materials is essential in optimal control of many-body interactions and correlations. In a multidomain system this signifies nonlocal coherence and emergence of collective phenomena, particularly in layered 2D quantum materials possessing novel electronic structures and high carrier mobilities. Here we report nonlocal ac electron coherence induced in dispersed MoS2 flake domains, using coherent spatial self-phase modulation (SSPM). The gap-dependent nonlinear dielectric susceptibility χ(3) measured is surprisingly large, where direct interband transition and two-photon SSPM are responsible for excitations above and below the bandgap, respectively. A wind-chime model is proposed to account for the emergence of the ac electron coherence. Furthermore, all-optical switching is achieved based on SSPM, especially with two-color intraband coherence, demonstrating that electron coherence generation is a ubiquitous property of layered quantum materials.

19.
Ecotoxicol Environ Saf ; 145: 235-243, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28738207

RESUMO

Metals and metalloids in soil could be transferred into reproductive organs and floral rewards of hyperaccumulator plants and influence their reproductive success, yet little is known whether non-hyperaccumulator plants can translocate heavy metals from soil into their floral organs and rewards (i.e., nectar and pollen) and, if so, whether plant reproduction will be affected. In our studies, summer squash (Cucurbita pepo L. cv. Golden Apple) was exposed to heavy-metal treatments during bud stage to investigate the translocation of soil-supplemented zinc, copper, nickel and lead into its floral organs (pistil, anther and nectary) and rewards (nectar and pollen) as well as floral metal accumulation effects on its reproduction. The results showed that metals taken up by squash did translocate into its floral organs and rewards, although metal accumulation varied depending on different metal types and concentrations as well as floral organ/reward types. Mean foraging time of honey bees to each male and female flower of squash grown in metal-supplemented soils was shorter relative to that of plants grown in control soils, although the visitation rate of honeybees to both male and female flowers was not affected by metal treatments. Pollen viability, pollen removal and deposition as well as mean mass per seed produced by metal-treated squash that received pollen from plants grown in control soils decreased with elevated soil-supplemented metal concentrations. The fact that squash could translocate soil-supplemented heavy metals into floral organs and rewards indicated possible reproductive consequences caused either directly (i.e., decreasing pollen viability or seed mass) or indirectly (i.e., affecting pollinators' visitation behavior to flowers) to plant fitness.


Assuntos
Cucurbita/química , Flores/química , Metais Pesados/análise , Néctar de Plantas/química , Pólen/química , Poluentes do Solo/análise , Animais , Abelhas/fisiologia , Cucurbita/fisiologia , Metais Pesados/toxicidade , Polinização/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Sementes/efeitos dos fármacos , Poluentes do Solo/toxicidade
20.
Tumour Biol ; 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27726097

RESUMO

Dendritic cells (DC) have been exploited for vaccination against cancer for years. DC loading autologous tumor lysate (ATL-DC) have been assessed in ongoing clinical trials, but frequently do not meet expectation. In this study, we found that mice immunized with ATL-DC induced less protective anti-tumor effect than immunized with DC alone. The percentage of CD8+ T cells and the lysis efficiency of CTLs to auto tumor cells in ATL-DC vaccination group was less than that of DC group. Moreover, vaccination of mice with ATL-DC also promoted tumor angiogenesis by analyzing the CD31 positive microvessel density and hemoglobin content of tumor specimens. Human umbilical vein endothelial cells (HUVEC) have been proved effective in the anti-angiogenesis immunity against cancer. However, in the following research we found that the anti-tumor effect was attenuated while immunized mice with HUVEC combined with ATL-DC (HUVEC + ATL-DC). Furthermore, immunized mice with HUVEC + ATL-DC profoundly increased the tumor angiogenesis by analyzing the microvessel density and hemoglobin content of tumor specimens. These data suggest that vaccination using ATL-DC antagonized HUVEC induced anti-angiogenesis effect. Our research for the first time indicated that ATL-DC have the potential to promote the process of tumor angiogenesis in vivo. As vaccines based on DC loading autologous tumor lysate have been used in clinical, this find warned that the safety of this kind of vaccine should be taken into consideration seriously.

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