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1.
Proc Natl Acad Sci U S A ; 120(3): e2208927120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36626550

RESUMO

The process of oncogene-induced senescence (OIS) and the conversion between OIS and malignant transformation during carcinogenesis is poorly understood. Here, we show that following overactivation of oncogene Ras in lung epithelial cells, high-level transforming growth factor ß1 (TGF-ß1)-activated SMAD3, but not SMAD2 or SMAD4, plays a determinant role in inducing cellular senescence independent of the p53/p16/p15 senescence pathways. Importantly, SMAD3 binds a potential tumor suppressor ATOH8 to form a transcriptional complex that directly represses a series of cell cycle-promoting genes and consequently causes senescence in lung epithelial cells. Interestingly, the prosenescent SMAD3 converts to being oncogenic and essentially facilitates oncogenic Ras-driven malignant transformation. Furthermore, depleting Atoh8 rapidly accelerates oncogenic Ras-driven lung tumorigenesis, and lung cancers driven by mutant Ras and Atoh8 loss, but not by mutant Ras only, are sensitive to treatment of a specific SMAD3 inhibitor. Moreover, hypermethylation of the ATOH8 gene can be found in approximately 12% of clinical lung cancer cases. Together, our findings demonstrate not only epithelial cellular senescence directed by a potential tumor suppressor-controlled transcriptional program but also an important interplay between the prosenescent and transforming effects of TGF-ß/SMAD3, potentially laying a foundation for developing early detection and anticancer strategies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Transformação Celular Neoplásica , Genes ras , Proteína Smad3 , Humanos , Transformação Celular Neoplásica/genética , Senescência Celular/genética , Genes Supressores de Tumor , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
2.
Proc Natl Acad Sci U S A ; 117(38): 23869-23878, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32907937

RESUMO

Mounting evidence has associated Zika virus (ZIKV) infection with congenital malformations, including microcephaly, which raises global alarm. Nonetheless, mechanisms by which ZIKV disrupts neurogenesis and causes microcephaly are far from being understood. In this study, we discovered direct effects of ZIKV on neural progenitor cell development by inducing caspase-1- and gasdermin D (GSDMD)-mediated pyroptotic cell death, linking ZIKV infection with the development of microcephaly. Importantly, caspase-1 depletion or its inhibitor VX-765 treatment reduced ZIKV-induced inflammatory responses and pyroptosis, and substantially attenuated neuropathology and brain atrophy in vivo. Collectively, our data identify caspase-1- and GSDMD-mediated pyroptosis in neural progenitor cells as a previously unrecognized mechanism for ZIKV-related pathological effects during neural development, and also provide treatment options for ZIKV-associated diseases.


Assuntos
Encefalopatias , Células-Tronco Neurais , Piroptose/fisiologia , Infecção por Zika virus , Zika virus , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/virologia , Encefalopatias/metabolismo , Encefalopatias/virologia , Células Cultivadas , Humanos , Camundongos , Microcefalia/metabolismo , Microcefalia/virologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/virologia , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologia
3.
Proc Natl Acad Sci U S A ; 116(28): 14019-14028, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31235588

RESUMO

It is well recognized that metastasis can occur early in the course of lung adenocarcinoma (LAD) development, and yet the molecular mechanisms driving this capability of rapid metastasis remain incompletely understood. Here we reported that a long noncoding RNA, LINC00673, was up-regulated in LAD cells. Of note, we first found that LINC00673-v4 was the most abundant transcript of LINC00673 in LAD cells and its expression was associated with adverse clinical outcome of LAD. In vitro and in vivo experiments demonstrated that LINC00673-v4 enhanced invasiveness, migration, and metastasis of LAD cells. Mechanistically, LINC00673-v4 augmented the interaction between DDX3 and CK1ε and thus the phosphorylation of dishevelled, which subsequently activated WNT/ß-catenin signaling and consequently caused aggressiveness of LAD. Antagonizing LINC00673-v4 suppressed LAD metastasis in vivo. Together, our data suggest that LINC00673-v4 is a driver molecule for metastasis via constitutively activating WNT/ß-catenin signaling in LAD and may represent a potential therapeutic target against the metastasis of LAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Caseína Quinase 1 épsilon/genética , RNA Helicases DEAD-box/genética , RNA Longo não Codificante/genética , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica , Ativação Transcricional , Via de Sinalização Wnt/genética
4.
J Cell Mol Med ; 24(14): 7884-7895, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452100

RESUMO

Tumour-associated macrophages (TAMs), which possess M2-like characters and are derived from immature monocytes in the circulatory system, represent a predominant population of inflammatory cells in solid tumours. TAM infiltration in tumour microenvironment can be used as an important prognostic marker in many cancer types and is a potential target for cancer prevention or treatment. VEGI-251 not only is involved in the inhibition of tumour angiogenesis, but also participates in the regulation of host immunity. This work aimed to investigate the involvement of VEGI-251 in the regulation of specific antitumour immunity. We found that recombinant human VEGI-251(rhVEGI-251) efficiently mediated the elimination of TAMs in tumour tissue in mice, and induced apoptosis of purified TAMs in vitro. During this process, caspase-8 and caspase-3 were activated, leading to PARP cleavage and apoptosis. Most importantly, we further elucidated the mechanism underlying VEGI-251-triggered TAM apoptosis, which suggests that ASK1, an intermediate component of the VEGI-251, activates the JNK pathway via TRAF2 in a potentially DR3-dependent manner in the process of TAM apoptosis. Collectively, our findings provide new insights into the basic mechanisms underlying the actions of VEGI-251 that might lead to future development of antitumour therapeutic strategies using VEGI-251 to target TAMs.


Assuntos
Antineoplásicos/farmacologia , Proteínas Recombinantes/farmacologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/farmacologia , Macrófagos Associados a Tumor/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Biomarcadores , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Imunofenotipagem , Camundongos , Modelos Moleculares , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/química , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/uso terapêutico , Macrófagos Associados a Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
BMC Med ; 18(1): 204, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32731873

RESUMO

BACKGROUND: Zika virus (ZIKV) infection is a global health problem, and its complications, including congenital Zika syndrome and Guillain-Barré syndrome, constitute a continued threat to humans. Unfortunately, effective therapeutics against ZIKV infection are not available thus far. METHODS: We screened the compounds collection consisting of 1789 FDA-approved drugs by a computational docking method to obtain anti-ZIKV candidate compounds targeting ZIKV RNA-dependent RNA polymerase (RdRp). SPR (BIAcore) assay was employed to demonstrate the candidate compounds' direct binding to ZIKV RdRp, and polymerase activity assay was used to determine the inhibitory effect on ZIKV RdRp-catalyzed RNA synthesis. The antiviral effects on ZIKV in vitro and in vivo were detected in infected cultured cells and in Ifnar1-/- mice infected by ZIKV virus using plaque assay, western blotting, tissue immunofluorescence, and immunohistochemistry. RESULTS: Here, we report that a first-in-class macrocyclic antibiotic, which has been clinically used to treat Clostridium difficile infection, fidaxomicin, potently inhibits ZIKV replication in vitro and in vivo. Our data showed that fidaxomicin was effective against African and Asian lineage ZIKV in a wide variety of cell lines of various tissue origins, and prominently suppressed ZIKV infection and significantly improved survival of infected mice. In addition, fidaxomicin treatment reduced the virus load in the brains and testes, and alleviated ZIKV-associated pathological damages, such as paralysis, hunching, and neuronal necrosis in the cerebra. Furthermore, our mechanistic study showed that fidaxomicin directly bound ZIKV NS5 protein and inhibited the RNA synthesis-catalyzing activity of ZIKV RdRp. CONCLUSIONS: Our data suggest that fidaxomicin may represent an effective anti-ZIKV agent. In the light that fidaxomicin is already a clinically used drug, there might be a promising prospect in the development of fidaxomicin to be an antiviral therapeutic.


Assuntos
Fidaxomicina/uso terapêutico , RNA Polimerase Dependente de RNA/uso terapêutico , Infecção por Zika virus/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Feminino , Fidaxomicina/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , RNA Polimerase Dependente de RNA/farmacologia , Células Vero , Infecção por Zika virus/patologia
6.
J Cell Mol Med ; 23(3): 1852-1864, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30515972

RESUMO

Long noncoding RNAs (lncRNAs) are involved in the pathology of various tumours, including non-small cell lung cancer (NSCLC). However, the underlying molecular mechanisms of their specific association with NSCLC have not been fully elucidated. Here, we report that a cytoplasmic lncRNA, DUXAP9-206 is overexpressed in NSCLC cells and closely related to NSCLC clinical features and poor patient survival. We reveal that DUXAP9-206 induced NSCLC cell proliferation and metastasis by directly interacting with Cbl-b, an E3 ubiquitin ligase, and reducing the degradation of epidermal growth factor receptor (EGFR) and thereby augmenting EGFR signaling in NSCLC. Notably, correlations between DUXAP9-206 and activated EGFR signaling were also validated in NSCLC patient specimens. Collectively, our findings reveal the novel molecular mechanisms of DUXAP9-206 in mediating the progression of NSCLC and DUXAP9-206 may serve as a potential target for NSCLC therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas c-cbl/metabolismo , RNA Longo não Codificante/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Movimento Celular , Proliferação de Células , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Proteínas Proto-Oncogênicas c-cbl/genética , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Infect Dis ; 217(12): 1942-1951, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29518228

RESUMO

Zika virus (ZIKV) is a mosquito-borne virus that has been identified as a cause of several severe disease manifestations, including congenital microcephaly and Guillain-Barré syndrome, meningoencephalitis, and myelitis. Previous studies showed that ZIKV-infected patients exhibited elevated plasma levels of interleukin 1ß (IL-1ß), indicating that ZIKV may activate inflammasomes. However, the molecular basis for its viral pathogenesis remains poorly understood. In this current study, we found that ZIKV infection caused severe inflammatory pathological changes and promoted IL-1ß production in vitro and in vivo. We here demonstrate that the maturation and secretion of IL-1ß during ZIKV infection was mediated by NLRP3 inflammasome activation and that ZIKV nonstructural protein 5 (NS5) facilitated the assembly of the NLRP3 inflammasome complex, leading to IL-1ß activation through interaction with NLRP3 and induction of reactive oxygen species production. Collectively, our data identify NLRP3 inflammasome-derived IL-1ß production as a critical feature of inflammation during ZIKV infection. These findings offer new insights into inflammasome-mediated diseases and may provide new therapeutic options for ZIKV-associated diseases.


Assuntos
Inflamassomos/metabolismo , Inflamação/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infecção por Zika virus/metabolismo , Zika virus/patogenicidade , Animais , Proteínas de Transporte/metabolismo , Linhagem Celular , Células HEK293 , Humanos , Inflamação/virologia , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Proteínas não Estruturais Virais/metabolismo
8.
Mol Cancer ; 16(1): 106, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28633632

RESUMO

BACKGROUND: The plasticity of cancer stem cells (CSCs)/tumor-initiating cells (T-ICs) suggests that multiple CSC/T-IC subpopulations exist within a tumor and that multiple oncogenic pathways collaborate to maintain the CSC/T-IC state. Here, we aimed to identify potential therapeutic targets that concomitantly regulate multiple T-IC subpopulations and CSC/T-IC-associated pathways. METHODS: A chemoresistant patient-derived xenograft (PDX) model of human esophageal squamous cell carcinoma (ESCC) was employed to identify microRNAs that contribute to ESCC aggressiveness. The oncogenic effects of microRNA-455-3p (miR-455-3p) on ESCC chemoresistance and tumorigenesis were examined by in vivo and in vitro chemoresistance, tumorsphere formation, side-population, and in vivo limiting dilution assays. The roles of miR-455-3p in activation of the Wnt/ß-catenin and transforming growth factor-ß (TGF-ß)/Smad pathways were determined by luciferase and RNA immunoprecipitation assays. RESULTS: We found that miR-455-3p played essential roles in ESCC chemoresistance and tumorigenesis. Treatment with a miR-455-3p antagomir dramatically chemosensitized ESCC cells and reduced the subpopulations of CD90+ and CD271+ T-ICs via deactivation of multiple stemness-associated pathways, including Wnt/ß-catenin and TGF-ß signaling. Importantly, miR-455-3p exhibited aberrant upregulation in various human cancer types, and was significantly associated with decreased overall survival of cancer patients. CONCLUSIONS: Our results demonstrate that miR-455-3p functions as an oncomiR in ESCC progression and may provide a potential therapeutic target to achieve better clinical outcomes in cancer patients.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , MicroRNAs/genética , Animais , Antagomirs/farmacologia , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago , Feminino , Inativação Gênica , Humanos , Masculino , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo , Antígenos Thy-1/genética , Antígenos Thy-1/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Virol ; 90(16): 7219-7230, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27252539

RESUMO

UNLABELLED: Dengue virus (DENV) is the most common mosquito-borne virus infecting humans and is currently a serious global health challenge. To establish infection in its host cells, DENV must subvert the production and/or antiviral effects of interferon (IFN). The aim of this study was to understand the mechanisms by which DENV suppresses IFN production. We determined that DENV NS4A interacts with mitochondrial antiviral signaling protein (MAVS), which was previously found to activate NF-κB and IFN regulatory factor 3 (IRF3), thus inducing type I IFN in the mitochondrion-associated endoplasmic reticulum membranes (MAMs). We further demonstrated that NS4A is associated with the N-terminal CARD-like (CL) domain and the C-terminal transmembrane (TM) domain of MAVS. This association prevented the binding of MAVS to RIG-I, resulting in the repression of RIG-I-induced IRF3 activation and, consequently, the abrogation of IFN production. Collectively, our findings illustrate a new molecular mechanism by which DENV evades the host immune system and suggest new targets for anti-DENV strategies. IMPORTANCE: Type I interferon (IFN) constitutes the first line of host defense against invading viruses. To successfully establish infection, dengue virus (DENV) must counteract either the production or the function of IFN. The mechanism by which DENV suppresses IFN production is poorly understood and characterized. In this study, we demonstrate that the DENV NS4A protein plays an important role in suppressing interferon production through binding MAVS and disrupting the RIG-I-MAVS interaction in mitochondrion-associated endoplasmic reticulum membranes (MAMs). Our study reveals that MAVS is a novel host target of NS4A and provides a molecular mechanism for DENV evasion of the host innate immune response. These findings have important implications for understanding the pathogenesis of DENV and may provide new insights into using NS4A as a therapeutic and/or prevention target.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Vírus da Dengue/imunologia , Dengue/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Interferon Tipo I/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Antivirais/metabolismo , Western Blotting , Células Cultivadas , Dengue/metabolismo , Dengue/virologia , Retículo Endoplasmático/metabolismo , Imunofluorescência , Células HEK293 , Células HeLa , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Fator Regulador 3 de Interferon/antagonistas & inibidores , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Monócitos/virologia , NF-kappa B/genética , NF-kappa B/metabolismo , Ligação Proteica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteínas não Estruturais Virais/genética
10.
J Biol Chem ; 290(41): 24678-88, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26286747

RESUMO

The molecular mechanism underlying constitutive activation of AKT signaling, which plays essential roles in astrocytoma progression, is not fully characterized. Increasing numbers of studies have reported that microRNAs are involved in the malignant behavior of astrocytoma cells via directly targeting multiple oncogenes or tumor suppressors. Here, we found that microRNA (miR)-542-3p expression was decreased in glioblastoma cell lines and astrocytoma tissues, and reduced levels of miR-542-3p expression correlated with high histopathological grades and poor prognosis of astrocytoma patients. Exogenous miR-542-3p suppressed glioblastoma cell invasion through not only targeting AKT1 itself but also directly down-regulating its two important upstream regulators, namely, integrin-linked kinase and PIK3R1. Notably, overexpressing miR-542-3p decreased AKT1 phosphorylation and directly and indirectly repressed nuclear translocation and transactivation activity of ß-catenin to exert its anti-invasive effect. Furthermore, the miR-542-3p expression level negatively correlated with AKT activity as well as levels of integrin-linked kinase and PIK3R1 in human astrocytoma specimens. These findings suggest that miR-542-3p acts as a negative regulator in astrocytoma progression and that miR-542-3p down-regulation contributes to aberrant activation of AKT signaling, leaving open the possibility that miR-542-3p may be a potential therapeutic target for high grade astrocytoma.


Assuntos
Glioblastoma/patologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , Linhagem Celular Tumoral , Classe Ia de Fosfatidilinositol 3-Quinase , Progressão da Doença , Regulação para Baixo/genética , Glioblastoma/diagnóstico , Glioblastoma/genética , Humanos , Gradação de Tumores , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/genética , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Regulação para Cima/genética , beta Catenina/metabolismo
12.
Cell Microbiol ; 17(1): 105-18, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25131332

RESUMO

Interferon-inducible transmembrane proteins 1, 2 and 3 (IFITM1, IFITM2 and IFITM3) have recently been identified as potent antiviral effectors that function to suppress the entry of a broad range of enveloped viruses and modulate cellular tropism independent of viral receptor expression. However, the antiviral effect and mechanisms of IFITMs in response to viral infections remain incompletely understood and characterized. In this work, we focused our investigation on the function of the extracellular IFITM3 protein. In cell models of DENV-2 infection, we found that IFITM3 contributed to both the baseline and interferon-induced inhibition of DENV entry. Most importantly, our study for the first time demonstrated the presence of IFITM-containing exosome in the extracellular environment, and identified an ability of cellular exosome to intercellularly deliver IFITM3 and thus transmit its antiviral effect from infected to non-infected cells. Thus, our findings provide new insights in the basic mechanisms underlying the actions of IFITM3, which might lead to future development of exosome-mediated anti-viral strategies using IFITM3 as a therapeutic agent. Conceivably, variations in the basal and inducible levels of IFITMs, as well as in intracellular and extracellular levels of IFITMs, might predict the severity of dengue virus infections among individuals or across species.


Assuntos
Antivirais/metabolismo , Vírus da Dengue/imunologia , Dengue/imunologia , Exossomos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/metabolismo , Vírus da Dengue/fisiologia , Internalização do Vírus
13.
J Pathol ; 235(3): 490-501, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25385148

RESUMO

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies, in which the NF-κB pathway plays an important role and is constitutively activated. Better understanding of the molecular pathogenesis of HCC and the NF-κB pathway are needed to improve patient outcomes. Herein, we identified an unappreciated protein involved in NF-κB-induced activation, Golgi phosphoprotein 3 (GOLPH3). The mRNA and protein expression levels of GOLPH3 were frequently up-regulated in HCC and GOLPH3 expression correlated closely with clinical stage and survival in both the testing and validation cohorts. Ectopic over-expression of GOLPH3 in PLC/PRF/5 (PLC) and Huh7 HCC cells protected against cisplatin-induced apoptosis, promoted angiogenesis and proliferation and increased the aggressiveness of HCC cells in vitro and in vivo, whereas inhibition of GOLPH3 led to decreased aggressiveness. Through analysis of two published HCC patient profiles, GOLPH3 expression significantly correlated with NF-κB signalling. Furthermore, we demonstrated that GOLPH3 promoted K63-linked polyubiquitination of tumour necrosis factor receptor-associated factor 2 (TRAF2), receptor interacting protein (RIP) and NF-κB essential modulator (NEMO) and substantially sustained the activation of NF-κB in HCC cells. Taken together, our findings provided evidence that GOLPH3 is a prognostic and/or potential therapeutic biomarker for HCC patients and plays an important role in activation of the NF-κB pathway during HCC progression.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Proteínas de Membrana/fisiologia , NF-kappa B/fisiologia , Invasividade Neoplásica/fisiopatologia , Transdução de Sinais/fisiologia , Animais , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Feminino , Xenoenxertos , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
14.
Gut ; 64(1): 26-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24667177

RESUMO

OBJECTIVE: Transducin (ß)-like 1 X-linked receptor 1 (TBL1XR1) plays an important role in controlling the precisely regulated switch between gene repression and gene activation in transcriptional regulation. We investigated its biological function and clinical significance in esophageal squamous cell carcinoma (ESCC). DESIGN: Immunoblotting and immunochemistry were used to determine TBL1XR1 expression in ESCC cell lines, ESCC clinical tissues and 230 clinicopathologically characterised ESCC specimens. The role of TBL1XR1 in lymphangiogenesis and lymphatic metastasis was examined by tube formation, cell invasion and wound-healing assays in vitro, and by a popliteal lymph node metastasis model in vivo. The molecular mechanism by which TBL1XR1 upregulates vascular endothelial growth factor C (VEGF-C) expression was explored using real-time PCR, ELISA, luciferase reporter assay and chromatin immunoprecipitation. RESULTS: TBL1XR1 expression was significantly upregulated in ESCC, positively correlated with disease stage and patient survival, and identified as an independent prognostic factor for patient outcome. We found that TBL1XR1 overexpression promoted lymphangiogenesis and lymphatic metastasis in ESCC in vitro and in vivo, whereas TBL1XR1 silencing had the converse effect. We demonstrated that TBL1XR1 induced VEGF-C expression by binding to the VEGF-C promoter. We confirmed the correlation between TBL1XR1 and VEGF-C expression in a large cohort of clinical ESCC samples and through analysis of published datasets in gastric, colorectal and breast cancer. CONCLUSIONS: Our results demonstrated that TBL1XR1 induced lymphangiogenesis and lymphatic metastasis in ESCC via upregulation of VEGF-C, and may represent a novel prognostic biomarker and therapeutic target for patients with ESCC.


Assuntos
Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/secundário , Linfangiogênese , Proteínas Nucleares/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Carcinoma de Células Escamosas do Esôfago , Humanos , Metástase Linfática , Células Tumorais Cultivadas , Fator C de Crescimento do Endotélio Vascular/fisiologia
15.
Int J Cancer ; 136(4): E39-50, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25142862

RESUMO

Multiple nodes in the one-carbon metabolism pathway play important regulatory roles in cancer cell growth and tumorigenesis. The specific biological functions of metabolic enzymes in regulating the signaling pathways that are associated with tumor cell growth and survival, however, remain unclear. Our current study found that phosphoserine aminotransferase 1 (PSAT1), an enzyme catalyzing serine biosynthesis, was significantly up-regulated in non-small cell lung cancer (NSCLC) and was involved in the regulation of E2F activity. Loss- and gain-of-function experiments demonstrated that PSAT1 promoted cell cycle progression, cell proliferation and tumorigenesis. Mechanistic study suggested that elevated PSAT1 led to inhibition of cyclin D1 degradation and subsequently an alteration in Rb-E2F pathway activity, which in turn enhanced G1 progression and proliferation of NSCLC cells. Moreover, phosphorylation of cyclin D1 at threonine 286 by GSK-3ß was required for PSAT1-induced blockage of cyclin D1 degradation. We also found that the activity of p70S6K mediated the effects of PSAT1 on GSK-3ß phosphorylation and cyclin D1 degradation. We further identified that PSAT1 was over-expressed in NSCLC and predicted poor clinical outcome of patients with the disease. Correlation analysis showed that PSAT1 expression positively correlated with the levels of phosphorylated GSK-3ß, cyclin D1 and phosphorylated Rb in NSCLC primary tumors. These findings uncover a mechanism for constitutive activation of E2F via which unrestrained cell cycle progression occurs in NSCLC and may represent a prognostic biomarker and therapeutic target.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Proliferação de Células , Ciclina D1/metabolismo , Neoplasias Pulmonares/enzimologia , Transaminases/fisiologia , Animais , Linhagem Celular Tumoral , Fatores de Transcrição E2F/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosforilação , Prognóstico , Processamento de Proteína Pós-Traducional , Proteólise , Transdução de Sinais , Transcriptoma , Carga Tumoral
17.
Int J Cancer ; 135(7): 1531-42, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24550137

RESUMO

A microRNA usually has the ability to coordinately repress multiple target genes and therefore are associated with many pathological conditions such as human cancer. Our understanding of the biological roles of microRNAs in lung cancer, however, remains incomplete. In this study, we identified miR-503 as a tumor-suppressive microRNA in human non-small cell lung carcinoma (NSCLC), whose expression level correlates inversely with overall survival in NSCLC patients. Ectopic expression of miR-503 suppressed tumor cell proliferation and metastasis-related traits in vitro as well as in vivo, supporting a anti-cancer role of the microRNA in NSCLC progression. Mechanistic study revealed that oncogenic PI3K p85 and IKK-ß were direct targets of miR-503. Overexpression of either PI3K p85 or IKK-ß partially restored the malignant properties of NSCLC cells in the presence of miR-503. Taken together, our data demonstrate miR-503 inhibits the malignant phenotype of NSCLC by targeting PI3K p85 and IKK-ß and might play a suppressive role in the pathogenesis of NSCLC, thus providing new insights in developing novel diagnostic and therapeutic approaches.


Assuntos
Adenocarcinoma/secundário , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/secundário , Quinase I-kappa B/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Animais , Apoptose , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Quinase I-kappa B/genética , Técnicas Imunoenzimáticas , Imunoprecipitação , Hibridização In Situ , Luciferases/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Fosfatidilinositol 3-Quinases/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Cicatrização , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Biochem Biophys Res Commun ; 450(1): 899-905, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24971537

RESUMO

Non-small cell lung cancer (NSCLC) remains a highly challenging and deadly malignancy with limited improvements in prognosis over years. Further understanding the molecular events involved in NSCLC oncogenesis and progression will help develop new and effective therapeutic strategies. In this study, we identified a ubiquitous up-regulation of DEPDC1B in NSCLC cell lines and clinical specimens, as well as its inverse correlation with patient survival. Ectopic expression of DEPDC1B endowed NSCLC cells with enhanced migration and invasion, while silencing its expression suppressed these traits. Mechanistic study showed that DEPDC1B was able to activate Wnt/ß-catenin signaling, and that depletion of TCF4 or LEF1 abrogated the biological effects of DEPDC1B on cellular migration and invasion. Taken together, our data demonstrate that DEPDC1B might confer metastasis-related malignant phenotype to NSCLC in a Wnt/ß-catenin dependent manner, providing new insights in developing novel anti-NSCLC strategies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Cateninas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Linhagem Celular Tumoral , Movimento Celular , Humanos , Invasividade Neoplásica , Transdução de Sinais
19.
Gastroenterology ; 143(4): 995-1005.e12, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22732732

RESUMO

BACKGROUND & AIMS: The flotillin family of proteins, including flotillin-1 (FLOT1 or Reggie-2), are lipid raft proteins that initiate receptor kinase signaling and are up-regulated in several tumor types. We investigated the role of FLOT1 signaling and activation of the transcription factor nuclear factor (NF)-κB in esophageal squamous cell carcinoma (ESCC) cells. METHODS: We used immunoblot and immunochemical analyses to determine levels of the lipid raft-associated protein FLOT1 in ESCC cell lines and 432 ESSC samples from patients; primary normal esophageal epithelial cells and matched adjacent nontumor tissues were used as controls. We determined the ability of FLOT1 to activate NF-κB using kinase, electrophoretic mobility shift, and luciferase reporter assays. We measured the effects of FLOT1 overexpression and knockdown with short hairpin RNAs in ESCC cell lines using colony formation, anchorage-independent growth, chicken chorioallantoic membrane, transwell matrix penetration, and Annexin V-binding assays. We analyzed growth of ESCC xenograft tumors in nude mice. RESULTS: Levels of FLOT1 were increased in ESCC cell lines and samples from patients, compared with controls; protein levels correlated with disease stage and survival time. Overexpression of FLOT1 in Kyse30 and Kyse510 ESCC cell lines increased proliferation, anchorage-independent growth, and invasive activity and protected them from apoptosis. FLOT1-transduced ESCC cells formed larger tumors in nude mice than control cells (transduced with only the vector). FLOT1 facilitated recruitment of the tumor necrosis factor-α receptor to lipid rafts; promoted K63-linked polyubiquitination of the signaling intermediaries tumor necrosis factor receptor associated factor 2, receptor interacting protein, and NEMO; and sustained the activation of NF-κB. Levels of FLOT1 correlated with activation of NF-κB in ESCC samples from patients. CONCLUSIONS: The lipid raft protein FLOT1 is up-regulated in ESCC cell lines and samples from patients and promotes ESCC cell proliferation and tumor growth in mice. FLOT1 activates tumor necrosis factor-α receptor signaling and sustains activation of NF-κB in ESCC cells.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais , Animais , Apoptose , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Distribuição de Qui-Quadrado , Progressão da Doença , Endotélio/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/metabolismo , Feminino , Humanos , Quinase I-kappa B/metabolismo , Masculino , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Transplante Heterólogo , Ubiquitina/metabolismo , Regulação para Cima
20.
J Pathol ; 226(3): 534-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21960069

RESUMO

Stomatin-like protein 2 (STOML2), a member of the stomatin family, has been reported to be up-regulated in several types of human cancers. The clinical significance and biological role of STOML2 in gliomas remain largely unknown. Here, we describe the significantly up-regulated expression of STOML2 in glioma cell lines and glioma tissues at both the transcriptional and translational levels. Silencing endogenous STOML2 in glioma cells and primary glioma cells drastically reduced their migratory speed and invasive ability, associated with induction of matrix metallopeptidase 9 (MMP-9). We also demonstrated that knockdown of STOML2 significantly inhibited the transcriptional activity of NF-κB and repressed the expression levels of NF-κB target genes, including MMP-9. A luciferase reporter assay revealed that the impact of STOML2 on MMP-9 expression is NF-κB-dependent. Immunohistochemical analysis showed that the up-regulation of STOML2 was significantly correlated with the WHO histological grade of gliomas (p < 0.001). Patients with higher STOML2 expression levels had an overall shorter survival time, whereas patients with lower expression of STOML2 had a longer survival time. A multivariate analysis revealed that STOML2 expression might be an independent prognostic indicator for the survival of glioma patients. Taken together, our results suggest that overexpression of STOML2 is associated with glioma aggressiveness and may represent an independent prognostic factor for the outcome of glioma patients.


Assuntos
Proteínas Sanguíneas/fisiologia , Glioma/fisiopatologia , Inibidores de Metaloproteinases de Matriz , Proteínas de Membrana/fisiologia , NF-kappa B/antagonistas & inibidores , Invasividade Neoplásica/fisiopatologia , Proteínas de Neoplasias/fisiologia , Adolescente , Adulto , Idoso , Proteínas Sanguíneas/deficiência , Proteínas Sanguíneas/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Criança , Pré-Escolar , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes/métodos , Inativação Gênica/fisiologia , Glioma/metabolismo , Glioma/patologia , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Invasividade Neoplásica/patologia , Proteínas de Neoplasias/genética , Prognóstico , Transdução de Sinais/fisiologia , Ativação Transcricional/fisiologia , Regulação para Cima , Adulto Jovem
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