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1.
Carcinogenesis ; 42(7): 995-1007, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34089582

RESUMO

MicroRNAs, as a group of post-transcriptional regulators, regulate multiple pathological processes including metastasis during tumor development. Here, we demonstrated the metastasis-suppressive function of microRNA (miR)-338-5p in esophageal squamous cell carcinoma (ESCC). Overexpression of miR-338-5p had inhibitory effect on invasive ability of ESCC cells and extracellular matrix degradation, whereas silencing miR-338-5p had opposite effects. Mechanistically, miR-338-5p directly targeted the 3' untranslated regions of hepatocellular growth factor receptor cMet (cMET) and epidermal growth factor receptor (EGFR). As a result, miR-338-5p inhibited the downstream signaling cascades of cMET and EGFR and repressed cMET- and EGFR-mediated ESCC cell invasion. Re-expression of cMET or EGFR in miR-338-5p overexpressing ESCC cells was sufficient to derepress ESCC cell invasion both in vitro and in vivo. We further showed that such manipulation downregulated the expression and secretion of matrix metalloproteinases 2 and 9, which resulted in impaired extracellular matrix degradation and cell invasion. Most importantly, systemic delivery of miR-338-5p mimic significantly inhibited metastasis of ESCC cells in nude mice. Taken together, our results uncovered a previously unknown mechanism through which miR-338-5p suppresses ESCC invasion and metastasis by regulating cMET/EGFR-matrix metalloproteinase 2/9 axis and highlighted the potential significance of miR-338-5p-based therapy in treating patients with metastatic ESCC.


Assuntos
Neoplasias Esofágicas/prevenção & controle , Carcinoma de Células Escamosas do Esôfago/prevenção & controle , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/prevenção & controle , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Apoptose , Proliferação de Células , Receptores ErbB/antagonistas & inibidores , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , MicroRNAs/administração & dosagem , Invasividade Neoplásica , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Proc Natl Acad Sci U S A ; 114(36): 9683-9688, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28831010

RESUMO

Nasopharyngeal carcinoma (NPC) most frequently occurs in southern China and southeast Asia. Epidemiology studies link NPC to genetic predisposition, Epstein-Barr virus (EBV) infection, and environmental factors. Genetic studies indicate that mutations in chromatin-modifying enzymes are the most frequent genetic alterations in NPC. Here, we used H3K27ac chromatin immune precipitation followed by deep sequencing (ChIP-seq) to define the NPC epigenome in primary NPC biopsies, NPC xenografts, and an NPC cell line, and compared them to immortalized normal nasopharyngeal or oral epithelial cells. We identified NPC-specific enhancers and found these enhancers were enriched with nuclear factor κB (NF-κB), IFN-responsive factor 1 (IRF1) and IRF2, and ETS family members ETS1 motifs. Normal cell-specific enhancers were enriched with basic leucine zipper family members and TP53 motifs. NPC super-enhancers with extraordinarily broad and high H3K27ac signals were also identified, and they were linked to genes important for oncogenesis including ETV6. ETV6 was also highly expressed in NPC biopsies by immunohistochemistry. High ETV6 expression correlated with a poor prognosis. Furthermore, we defined the EBV episome epigenetic landscapes in primary NPC tissue.


Assuntos
Carcinoma/genética , Elementos Facilitadores Genéticos , Neoplasias Nasofaríngeas/genética , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Idoso , Animais , Azepinas/farmacologia , Carcinoma/etiologia , Carcinoma/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos/efeitos dos fármacos , Epigênese Genética , Infecções por Vírus Epstein-Barr/complicações , Feminino , Genoma Viral , Xenoenxertos , Sequenciamento de Nucleotídeos em Larga Escala , Código das Histonas/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/etiologia , Neoplasias Nasofaríngeas/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Prognóstico , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologia , Adulto Jovem , Variante 6 da Proteína do Fator de Translocação ETS
3.
BMC Cancer ; 17(1): 409, 2017 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-28601093

RESUMO

BACKGROUND: Granulin-epithelin precursor (GEP) is a secretory growth factor, which has been demonstrated to control cancer growth, invasion, drug resistance and immune escape. Our previous studies and others also demonstrated its potential in targeted therapy. Comprehensive characterization of GEP partner on cancer cells are warranted. We have previously shown that GEP interacted with heparan sulfate on the surface of liver cancer cells and the interaction is crucial for GEP-mediated signaling transduction. This study aims to characterize GEP protein partner at the cell membrane with the co-immunoprecipitation and mass spectrometry approach. METHODS: The membrane fraction from liver cancer model Hep3B was used for capturing binding partner with the specific monoclonal antibody against GEP. The precipitated proteins were analyzed by mass spectrometry. After identifying the GEP binding partner, this specific interaction was validated in additional liver cancer cell line HepG2 by co-immunoprecipitation using GRP78 and GEP antibodies, respectively, as the bait. GRP78 transcript levels in hepatocellular carcinoma (HCC) clinical samples (n = 77 pairs) were examined by real-time quantitative RT-PCR. GEP and GRP78 protein expressions were investigated by immunohistochemistry on paraffin sections. RESULTS: We identified the GEP-binding protein as 78-kDa glucose-regulated protein (GRP78, also named heat shock 70-kDa protein 5, HSPA5). This interaction was validated in independent HCC cell lines. Increased GRP78 mRNA levels were demonstrated in liver cancer tissues compared with the paralleled liver tissues (t-test, P = 0.002). GRP78 and GEP transcript levels were significantly correlated (Spearman's correlation, P = 0.001), and the proteins were also detectable in the cytoplasm of liver cancer cells by immunohistochemical staining. CONCLUSIONS: GRP78 and GEP are interacting protein partners in liver cancer cells and may play a role in GEP-mediated cancer progression in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Choque Térmico/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Hepáticas/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico/genética , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Pessoa de Meia-Idade , Progranulinas , Ligação Proteica
4.
Mol Cell Proteomics ; 12(11): 3379-87, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23924514

RESUMO

MicroRNAs (miRNAs) regulate gene expression through translational repression and RNA degradation. Recently developed high-throughput proteomic methods measure gene expression changes at protein level and therefore can reveal the direct effects of miRNAs' translational repression. Here, we present a web server, ProteoMirExpress, that integrates proteomic and mRNA expression data together to infer miRNA-centered regulatory networks. With both types of high-throughput data from the users, ProteoMirExpress is able to discover not only miRNA targets that have decreased mRNA, but also subgroups of targets with suppressed proteins whose mRNAs are not significantly changed or with decreased mRNA whose proteins are not significantly changed, which are usually ignored by most current methods. Furthermore, both direct and indirect targets of miRNAs can be detected. Therefore, ProteoMirExpress provides more comprehensive miRNA-centered regulatory networks. We used several published data to assess the quality of our inferred networks and prove the value of our server. ProteoMirExpress is available online, with free access to academic users.


Assuntos
MicroRNAs/genética , MicroRNAs/metabolismo , Proteoma/genética , Proteoma/metabolismo , Proteômica/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Perfilação da Expressão Gênica/estatística & dados numéricos , Redes Reguladoras de Genes , Células HeLa , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Humanos , Proteômica/estatística & dados numéricos , Software
5.
Int J Mol Sci ; 16(2): 2530-58, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25625511

RESUMO

(-)-Epigallocatechin-3-gallate (EGCG), a major green tea polyphenol, has been shown to inhibit the proliferation of a variety of tumor cells. Epidemiological studies have shown that drinking green tea can reduce the incidence of nasopharyngeal carcinoma (NPC), yet the underlying mechanism is not well understood. In this study, the inhibitory effect of EGCG was tested on a set of Epstein Barr virus-negative and -positive NPC cell lines. Treatment with EGCG inhibited the proliferation of NPC cells but did not affect the growth of a non-malignant nasopharyngeal cell line, NP460hTert. Moreover, EGCG treated cells had reduced migration and invasive properties. The expression of the cell adhesion molecules E-cadherin and ß-catenin was found to be up-regulated by EGCG treatment, while the down-regulation of matrix metalloproteinases (MMP)-2 and MMP-9 were found to be mediated by suppression of extracellular signal-regulated kinase (ERK) phosphorylation and AP-1 and Sp1 transactivation. Spheroid formation by NPC cells in suspension was significantly inhibited by EGCG. Oral administration of EGCG was capable of suppressing tumor growth in xenografted mice bearing NPC tumors. Treatment with EGCG was found to elevate the expression of p53 and p21, and eventually led to apoptosis of NPC cells via caspase 3 activation. The nuclear translocation of NF-κB and ß-catenin was also suppressed by EGCG treatment. These results indicate that EGCG can inhibit the proliferation and invasiveness, and induce apoptosis, of NPC cells, making it a promising agent for chemoprevention or adjuvant therapy of NPC.


Assuntos
Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Moléculas de Adesão Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Gelatinases/metabolismo , Animais , Caderinas/metabolismo , Carcinoma , Caspase 3/metabolismo , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Camundongos , Camundongos SCID , NF-kappa B/metabolismo , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Transplante Heterólogo , Regulação para Cima/efeitos dos fármacos
6.
BMC Complement Altern Med ; 14: 300, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25127878

RESUMO

BACKGROUND: Abused women, who suffer from chronic psychological stress, have been shown to have shorter telomeres than never abused women. Telomere shortening is associated with increased risk of cell death, and it is believed that adopting health-promoting behaviors can help to increase the activity of telomerase, an enzyme that counters telomere shortening. Qigong is an ancient Chinese mind-body integration, health-oriented practice designed to enhance the function of qi, an energy that sustains well-being. Therefore, an assessor-blind, randomized, wait-list controlled trial was developed to evaluate the effect of a qigong intervention on telomerase activity (primary objective) and proinflammatory cytokines, perceived stress, perceived coping, and depressive symptoms (secondary objectives) in abused Chinese women. METHODS/DESIGN: A total of 240 Chinese women, aged ≥ 18 years, who have been abused by an intimate partner within the past three years will be recruited from a community setting in Hong Kong and randomized to receive either a qigong intervention or wait-list control condition as follows: the qigong intervention will comprise (i) a 2-hour group qigong training session twice a week for 6 weeks, (ii) a 1-hour follow-up group qigong exercise session once a week for 4 months, and (iii) a 30-minute self-practice qigong exercise session once a day for 5.5 months. The wait-list control group will receive qigong training after the intervention group completes the program. Upon completion of the qigong intervention program, it is expected that abused Chinese women in the intervention group will have higher levels of telomerase activity and perceived coping and lower levels of proinflammatory cytokines, perceived stress, and depressive symptoms than will abused Chinese women in the wait-list control group. DISCUSSION: This study will provide information about the effect of qigong exercise on telomerase activity and chronic psychological stress in abused Chinese women. The findings will inform the design of interventions to relieve the effects of IPV-related psychological stress on health. Also, the concept that health-promoting behaviors could slow down cellular aging might even motivate abused women to change their lifestyles. TRIAL REGISTRATION: Current Controlled Trials NCT02060123. Registered February 6, 2014.


Assuntos
Mulheres Maltratadas , Qigong/métodos , Estresse Psicológico/terapia , Telomerase/sangue , Listas de Espera , Adulto , Feminino , Hong Kong , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Estresse Psicológico/enzimologia , Adulto Jovem
7.
Mol Cancer ; 12(1): 128, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24156782

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is an epithelial malignancy strongly associated with Epstein-Barr virus (EBV). AT13387 is a novel heat shock protein 90 (Hsp90) inhibitor, which inhibits the chaperone function of Hsp90 and reduces expression of Hsp90-dependent client oncoproteins. This study aimed to evaluate both the in vitro and in vivo antitumor effects of AT13387 in the EBV-positive NPC cell line C666-1. RESULTS: Our results showed that AT13387 inhibited C666-1 cell growth and induced cellular senescence with the downregulation of multiple Hsp90 client oncoproteins EGFR, AKT, CDK4, and restored the protein expression of negative cell cycle regulator p27. We also studied the ability of AT13387 to restore p27 expression by downregulation of AKT and the p27 ubiquitin mediator, Skp2, using AKT inhibitor and Skp2 siRNA. In the functional study, AT13387 inhibited cell migration with downregulation of a cell migration regulator, HDAC6, and increased the acetylation and stabilization of α-tubulin. We also examined the effect of AT13387 on putative cancer stem cells (CSC) by 3-D tumor sphere formation assay. AT13387 effectively reduced both the number and size of C666-1 tumor spheres with decreased expression of NPC CSC-like markers CD44 and SOX2. In the in vivo study, AT13387 significantly suppressed tumor formation in C666-1 NPC xenografts. CONCLUSION: AT13387 suppressed cell growth, cell migration, tumor sphere formation and induced cellular senescence on EBV-positive NPC cell line C666-1. Also, the antitumor effect of AT13387 was demonstrated in an in vivo model. This study provided experimental evidence for the preclinical value of using AT13387 as an effective antitumor agent in treatment of NPC.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoindóis/farmacologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Acetilação , Animais , Carcinoma , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Desacetilase 6 de Histona , Histona Desacetilases/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/virologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Processamento de Proteína Pós-Traducional , Estabilidade Proteica , Fatores de Transcrição SOXB1/metabolismo , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Tubulina (Proteína)/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Hepatology ; 55(2): 491-505, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21953552

RESUMO

UNLABELLED: Emerging evidence implicates the chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) as a specific oncogene in human hepatocellular carcinoma (HCC). To better understand the molecular mechanisms underlying HCC cases carrying CHD1L amplification (>50% HCCs), we identified a CHD1L target, translationally controlled tumor protein (TCTP), and investigated its role in HCC progression. Here, we report that CHD1L protein directly binds to the promoter region (nt -733 to -1,027) of TCTP and activates TCTP transcription. Overexpression of TCTP was detected in 40.7% of human HCC samples analyzed and positively correlated with CHD1L overexpression. Clinically, overexpression of TCTP was significantly associated with the advanced tumor stage (P = 0.037) and overall survival time of HCC patients (P = 0.034). In multivariate analyses, TCTP was determined to be an independent marker associated with poor prognostic outcomes. In vitro and in vivo functional studies in mice showed that TCTP has tumorigenic abilities, and overexpression of TCTP induced by CHD1L contributed to the mitotic defects of tumor cells. Further mechanistic studies demonstrated that TCTP promoted the ubiquitin-proteasome degradation of Cdc25C during mitotic progression, which caused the failure in the dephosphorylation of Cdk1 on Tyr15 and decreased Cdk1 activity. As a consequence, the sudden drop of Cdk1 activity in mitosis induced a faster mitotic exit and chromosome missegregation, which led to chromosomal instability. The depletion experiment proved that the tumorigenicity of TCTP was linked to its role in mitotic defects. CONCLUSION: Collectively, we reveal a novel molecular pathway (CHD1L/TCTP/Cdc25C/Cdk1), which causes the malignant transformation of hepatocytes with the phenotypes of accelerated mitotic progression and the production of aneuploidy.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Segregação de Cromossomos , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína Quinase CDC2/metabolismo , Divisão Celular , Transformação Celular Neoplásica , Progressão da Doença , Eletroforese em Gel Bidimensional , Fase G2 , Células Hep G2 , Humanos , Proteína Tumoral 1 Controlada por Tradução , Regulação para Cima , Fosfatases cdc25/metabolismo
9.
Chin J Cancer ; 32(4): 205-12, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22704487

RESUMO

The discovery of induced pluripotent stem cells(iPSCs) is a promising advancement in the field of regenerative medicine. Previous studies have indicated that the teratoma-forming propensity of iPSCs is variable; however, the relationship between tumorigenic potential and genomic instability in human iPSCs (HiPSCs) remains to be fully elucidated. Here, we evaluated the malignant potential of HiPSCs by using both colony formation assays and tumorigenicity tests. We demonstrated that HiPSCs formed tumorigenic colonies when grown in cancer cell culture medium and produced malignancies in immunodeficient mice. Furthermore, we analyzed genomic instability in HiPSCs using whole-genome copy number variation analysis and determined that the extent of genomic instability was related with both the cells' propensity to form colonies and their potential for tumorigenesis. These findings indicate a risk for potential malignancy of HiPSCs derived from genomic instability and suggest that quality control tests, including comprehensive tumorigenicity assays and genomic integrity validation, should be rigorously executed before the clinical application of HiPSCs. In addition, HiPSCs should be generated through the use of combined factors or other approaches that decrease the likelihood of genomic instability.


Assuntos
Carcinogênese , Variações do Número de Cópias de DNA , Instabilidade Genômica , Células-Tronco Pluripotentes Induzidas , Teratoma/etiologia , Animais , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/transplante , Camundongos , Camundongos SCID , Células NIH 3T3 , Fator 3 de Transcrição de Octâmero/metabolismo , Teratocarcinoma/etiologia , Ensaio Tumoral de Célula-Tronco
10.
Nat Commun ; 14(1): 1912, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024479

RESUMO

Despite the intense CD8+ T-cell infiltration in the tumor microenvironment of nasopharyngeal carcinoma, anti-PD-1 immunotherapy shows an unsatisfactory response rate in clinical trials, hindered by immunosuppressive signals. To understand how microenvironmental characteristics alter immune homeostasis and limit immunotherapy efficacy in nasopharyngeal carcinoma, here we establish a multi-center single-cell cohort based on public data, containing 357,206 cells from 50 patient samples. We reveal that nasopharyngeal carcinoma cells enhance development and suppressive activity of regulatory T cells via CD70-CD27 interaction. CD70 blocking reverts Treg-mediated suppression and thus reinvigorate CD8+ T-cell immunity. Anti-CD70+ anti-PD-1 therapy is evaluated in xenograft-derived organoids and humanized mice, exhibiting an improved tumor-killing efficacy. Mechanistically, CD70 knockout inhibits a collective lipid signaling network in CD4+ naïve and regulatory T cells involving mitochondrial integrity, cholesterol homeostasis, and fatty acid metabolism. Furthermore, ATAC-Seq delineates that CD70 is transcriptionally upregulated by NFKB2 via an Epstein-Barr virus-dependent epigenetic modification. Our findings identify CD70+ nasopharyngeal carcinoma cells as a metabolic switch that enforces the lipid-driven development, functional specialization and homeostasis of Tregs, leading to immune evasion. This study also demonstrates that CD70 blockade can act synergistically with anti-PD-1 treatment to reinvigorate T-cell immunity against nasopharyngeal carcinoma.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Animais , Camundongos , Linfócitos T Reguladores , Carcinoma Nasofaríngeo/genética , Ligante CD27/genética , Ligante CD27/metabolismo , Herpesvirus Humano 4/metabolismo , Neoplasias Nasofaríngeas/genética , Lipídeos , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Microambiente Tumoral
11.
Int J Cancer ; 131(8): 1930-40, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22261816

RESUMO

Nasopharyngeal carcinoma (NPC) is strongly associated with Epstein-Barr virus (EBV). We reported that suberoylanilide hydroxamic acid (SAHA) induced EBV lytic cycle in EBV-positive gastric carcinoma cells and mediated enhanced cell death. However, expression of EBV lytic proteins was thought to exert antiapoptotic effect in EBV-infected cells. Here, we examined the in vitro and in vivo effects of SAHA on EBV lytic cycle induction in NPC cells and investigated the cellular consequences. Micromolar concentrations of SAHA significantly induced EBV lytic cycle in EBV-positive NPC cells. Increased apoptosis and proteolytic cleavage of poly(ADP-ribose) polymerase and caspase-3, -7 and -9 in EBV-positive versus EBV-negative NPC cells were observed. More than 85% of NPC cells expressing immediate-early (Zta), early (BMRF1) or late (gp350/220) lytic proteins coexpressed cleaved caspase-3. Tracking of expression of EBV lytic proteins and cleaved caspase-3 over time demonstrated that NPC cells proceeded to apoptosis following EBV lytic cycle induction. Inhibition of EBV DNA replication and late lytic protein expression by phosphonoformic acid did not impact on SAHA's induced cell death in NPC, indicating that early rather than late phase of EBV lytic cycle contributed to the apoptotic effect. In vivo effects of SAHA on EBV lytic cycle induction and tumor growth suppression were also observed in NPC xenografts in nude mice. Taken together, our data indicated that activation of lytic cycle from latent cycle of EBV by SAHA leads to apoptosis and tumor growth suppression of NPC thereby providing experimental evidence for virus-targeted therapy against EBV-positive cancer.


Assuntos
Apoptose/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/patologia , Herpesvirus Humano 4/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Replicação Viral/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Western Blotting , Carcinoma , Proliferação de Células/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/virologia , Feminino , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/virologia , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Vorinostat
12.
Mol Carcinog ; 51(12): 963-72, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22006341

RESUMO

2-methoxyestradiol (2ME2), an endogenous metabolite of 17-ß-estradiol, has been shown to induce apoptosis and cell cycle arrest in various tumor models. We have previously shown that 2ME2 induced endoreduplication in a well-differentiated nasopharyngeal carcinoma (NPC) HK-1 and a poorly differentiated C666-1 cell line. In the present study, we studied the survival factors involved in 2ME2-induced endoreduplicating NPC cells. In the HK-1 cells, knockdown of BcL-xL expression by siRNA resulted in the reduction of endoreduplication and an increase in the percentage of apoptosis. Further mechanistic study revealed that 2ME2 enhanced the expression of the phosphorylated form of STAT5 (p-STAT5-Y694), but not p-STAT3 (Y705) and p-STAT3 (S727), in the nucleus of HK-1 cells. Pre-treatment of cells with JAK/STAT inhibitor AG490 and STAT5 inhibitor resulted not only in the reduced expression of Bcl-xL, but also reduced the percentage of endoreduplicating cells. In contrast, 2ME2 enhanced the expression of p-STAT3 in the poorly differentiated C666-1 cells. Pharmacological inhibition of STAT3 or Bcl-2/xL resulted in a decrease in endoreduplication of C666-1 cells. Taken together, the expression of p-STAT5 and p-STAT3 was upregulated in 2ME2-induced endoreduplicating HK-1 and C666-1 cells, respectively. Combination of 2ME2 with Bcl-2/xL inhibitor is a novel strategy to reduce the formation of endoreduplicating cells during chemotherapeutic treatment of NPC. © 2011 Wiley Periodicals, Inc.


Assuntos
Endorreduplicação/efeitos dos fármacos , Estradiol/análogos & derivados , Neoplasias Nasofaríngeas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Fator de Transcrição STAT3/fisiologia , Fator de Transcrição STAT5/fisiologia , Proteína bcl-X/fisiologia , 2-Metoxiestradiol , Sequência de Bases , Western Blotting , Carcinoma , Linhagem Celular Tumoral , Estradiol/farmacologia , Citometria de Fluxo , Humanos , Carcinoma Nasofaríngeo , RNA Interferente Pequeno
13.
J Biol Chem ; 285(7): 4931-40, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-20007324

RESUMO

The existence of cancer stem cells (CSCs) or stem-like cancer cells (SLCCs) is regarded as the cause of tumor formation and recurrence. However, the origin of such cells remains controversial with two competing hypotheses: CSCs are either transformed from tissue adult stem cells or dedifferentiated from transformed progenitor cells. Compelling evidence has determined the chromosomal aneuploidy to be one of the hallmarks of cancer cells, indicating genome instability plays an important role in tumorigenesis, for which CSCs are believed to be the initiator. To gain direct evidence that genomic instability is involved in the induction of SLCCs, we utilized multiple approaches to enhance genomic instability and monitored the percentage of SLCC in cultured cancer cells. Using side population (SP) cells as a marker for SLCC in human nasopharyngeal carcinoma (NPC) and CD133 for human neuroblastoma cells, we found that DNA damage inducers, UV and mitomycin C were capable of increasing SP cells in NPC CNE-2 and neuroblastoma SKN-SH cells. Likewise, either overexpression of a key regulator of cell cycle, Mad2, or knock down of Aurora B, an important kinase in mitosis, or Cdh1, a key E3 ligase in cell cycle, resulted in a significant increase of SP cells in CNE-2. More interestingly, enrichment of SP cells was observed in recurrent tumor tissues as compared with the primary tumor in the same NPC patients. Our study thus suggested that, beside transformation of tissue stem cells leading to CSC generation, genomic instability could be another potential mechanism resulting in SLCC formation, especially at tumor recurrence stage.


Assuntos
Instabilidade Genômica/fisiologia , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Antígeno AC133 , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antígenos CD/metabolismo , Aurora Quinase B , Aurora Quinases , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Citometria de Fluxo , Instabilidade Genômica/genética , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Cariotipagem , Proteínas Mad2 , Mitomicina/toxicidade , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/metabolismo , Peptídeos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Raios Ultravioleta/efeitos adversos
14.
Am J Pathol ; 176(4): 1828-40, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20110407

RESUMO

The novel pandemic influenza H1N1 (H1N1pdm) virus of swine origin causes mild disease but occasionally leads to acute respiratory distress syndrome and death. It is important to understand the pathogenesis of this new disease in humans. We compared the virus tropism and host-responses elicited by pandemic H1N1pdm and seasonal H1N1 influenza viruses in ex vivo cultures of human conjunctiva, nasopharynx, bronchus, and lung, as well as in vitro cultures of human nasopharyngeal, bronchial, and alveolar epithelial cells. We found comparable replication and host-responses in seasonal and pandemic H1N1 viruses. However, pandemic H1N1pdm virus differs from seasonal H1N1 influenza virus in its ability to replicate in human conjunctiva, suggesting subtle differences in its receptor-binding profile and highlighting the potential role of the conjunctiva as an additional route of infection with H1N1pdm. A greater viral replication competence in bronchial epithelium at 33 degrees C may also contribute to the slight increase in virulence of the pandemic influenza virus. In contrast with highly pathogenic influenza H5N1 virus, pandemic H1N1pdm does not differ from seasonal influenza virus in its intrinsic capacity for cytokine dysregulation. Collectively, these results suggest that pandemic H1N1pdm virus differs in modest but subtle ways from seasonal H1N1 virus in its intrinsic virulence for humans, which is in accord with the epidemiology of the pandemic to date. These findings are therefore relevant for understanding transmission and therapy.


Assuntos
Túnica Conjuntiva/virologia , Vírus da Influenza A Subtipo H1N1/metabolismo , Influenza Humana/virologia , Sistema Respiratório/virologia , Células Epiteliais Alveolares/metabolismo , Animais , Brônquios/citologia , Citocinas/metabolismo , Cães , Células Epiteliais/citologia , Humanos , Orthomyxoviridae/metabolismo , Pandemias , Estações do Ano , Especificidade da Espécie
15.
Hepatology ; 50(1): 122-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19441106

RESUMO

UNLABELLED: Amplification of 1q21 has been detected in 58% to 78% of primary hepatocellular carcinoma cases, suggesting that one or more oncogenes within the amplicon play a critical role in the development of this disease. The chromodomain helicase/adenosine triphosphatase DNA binding protein 1-like gene (CHD1L) is a recently identified oncogene localized at 1q21. Our previous studies have demonstrated that CHD1L has strong tumorigenic ability and confers high susceptibility to spontaneous tumors in a CHD1L-transgenic mouse model. In this study, we demonstrate that the antiapoptotic ability of CHD1L is associated with its interaction with Nur77, a critical member of a p53-independent apoptotic pathway. As the first cellular protein identified to bind Nur77, CHD1L is able to inhibit the nucleus-to-mitochondria translocation of Nur77, which is the key step of Nur77-mediated apoptosis, resulting in the hindrance of the release of cytochrome c and the initiation of apoptosis. Knock-down of CHD1L expression by RNA interference could rescue the mitochondrial targeting of Nur77 and the subsequent apoptosis. Further studies found that the C-terminal Macro domain of CHD1L is responsible for the interaction with Nur77, and a CHD1L mutant lacking residues 600-897 failed to interact with Nur77 and prevented Nur77-mediated apoptosis. More importantly, we found that the inhibition of Nur77-mediated apoptosis by endogenous CHD1L is a critical biological cellular process in hepatocarcinogenesis. CONCLUSION: We demonstrate in this study that overexpression of CHD1L could sustain tumor cell survival by preventing Nur77-mediated apoptosis.


Assuntos
Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Núcleo Celular , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Mitocôndrias , Transporte Proteico , Receptores de Esteroides/metabolismo , Adenosina Trifosfatases/fisiologia , Sobrevivência Celular/genética , Humanos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares
16.
Eur J Anaesthesiol ; 27(3): 285-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20009936

RESUMO

BACKGROUND AND OBJECTIVE: Dexamethasone has been shown to prolong the duration of postoperative analgesia when given as an adjunct for peripheral nerve blocks. However, it has not been evaluated when given in conjunction with bupivacaine and clonidine to provide blockade of the brachial plexus at the interscalene level. The purpose of this investigation was to determine whether the addition of dexamethasone to interscalene brachial plexus block would prolong the duration of sensory analgesia in a group of patients undergoing outpatient shoulder arthroscopy. METHODS: This prospective, randomized, double-blind investigation was performed on 88 individuals undergoing shoulder arthroscopy. Patients received interscalene brachial plexus block using 20 ml of bupivacaine 5 mg ml(-1) with 1: 200,000 epinephrine and clonidine 75 microg. Patients were randomly assigned to receive either dexamethasone 8 mg or 0.9% NaCl as an adjuvant to the mixture. After discharge, patients recorded pain scores and analgesic consumption in a diary and estimated the time at which they perceived that the sensory block from the interscalene brachial plexus block resolved. This was based on pain, recovery of sensation and strength in the arm. Variables measured included demographics, timed pain intensity measurements, postoperative analgesic consumption, duration of analgesia and patient satisfaction. RESULTS: Dexamethasone prolonged median sensory (1457 vs. 833 min, P < 0.0001) and motor (1374 vs. 827 min, P < 0.0001) blockade compared with the control. At 24 h, the dexamethasone group had lower median verbal analogue scale scores compared with control (3.0 vs. 6.0). At 48 h, the two groups had similar median pain scores (4.0 vs. 5.0, dexamethasone vs. control, respectively). The opioid requirement in oxycodone equivalency was lower in the dexamethasone group than in the control group for the first 24 h, and similar thereafter. Median patient satisfaction scores were not significantly different between the two groups at 48 h (9.5 vs. 8.0, dexamethasone vs. control, respectively). CONCLUSION: The addition of dexamethasone to a bupivacaine-epinephrine-clonidine interscalene block prolongs sensory block and reduces opioid use.


Assuntos
Analgesia/métodos , Plexo Braquial/diagnóstico por imagem , Plexo Braquial/cirurgia , Bupivacaína/administração & dosagem , Dexametasona/administração & dosagem , Bloqueio Nervoso/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Plexo Braquial/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Fatores de Tempo
17.
Am J Cancer Res ; 10(6): 1710-1727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32642285

RESUMO

Oral tongue squamous cell carcinoma (OTSCC) has a distinctive cell sub-population known as tumor-initiating cells (TICs). CD271 is a functional TIC receptor in head and neck cancers. The molecular mechanisms governing CD271 up-regulation remains unclear. Oxidative stress is a contributing factor in TIC development. Here, we explored the potential role of NADPH oxidase 5 (NOX5) and its regulatory mechanism on the development of CD271-expressing OTSCC. Our results showed that the splice variant NOX5α is the most prevalent form expressed in head and neck cancers. NOX5α enhanced OTSCC proliferation, migration, and invasion. Overexpression of NOX5α increased the size of OTSCC xenograft significantly in vivo. The tumor-promoting functions of NOX5α were mediated through the reactive oxygen species (ROS)-generating property. NOX5α activated ERK singling and increased CD271 expression at the transcription level. Also, NOX5α reduces the sensitivity of OTSCC to cisplatin and natural killer cells. The findings indicate that NOX5α plays an important part in the development of TIC in OTSCC.

18.
Phytomedicine ; 63: 153058, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31394414

RESUMO

BACKGROUND: Sulforaphane (SFN), a natural compound present in cruciferous vegetable, has been shown to possess anti-cancer activities. Cancer stem cell (CSC) in bulk tumor is generally considered as treatment resistant cell and involved in cancer recurrence. The effects of SFN on nasopharyngeal carcinoma (NPC) CSCs have not yet been explored. PURPOSE: The present study aims to examine the anti-tumor activities of SFN on NPC cells with CSC-like properties and the underlying mechanisms. METHODS: NPC cells growing in monolayer culture, CSCs-enriched NPC tumor spheres, and also the NPC nude mice xenograft were used to study the anti-tumor activities of SFN on NPC. The population of cells expressing CSC-associated markers was evaluated using flow cytometry and aldehyde dehydrogenase (ALDH) activity assay. The effect of DNA methyltransferase 1 (DNMT1) on the growth of NPC cells was analyzed by using small interfering RNA (siRNA)-mediated silencing method. RESULTS: SFN was found to inhibit the formation of CSC-enriched NPC tumor spheres and reduce the population of cells with CSC-associated properties (SRY (Sex determining Region Y)-box 2 (SOX2) and ALDH). In the functional study, SFN was found to restore the expression of Wnt inhibitory factor 1 (WIF1) and the effect was accompanied with the downregulation of DNMT1. The functional activities of WIF1 and DNMT1 were confirmed using exogenously added recombinant WIF1 and siRNA knockdown of DNMT1. Moreover, SFN was found to inhibit the in vivo growth of C666-1 cells and enhance the anti-tumor effects of cisplatin. CONCLUSION: Taken together, we demonstrated that SFN could suppress the growth of NPC cells via the DNMT1/WIF1 axis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos Fitogênicos/farmacologia , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Isotiocianatos/farmacologia , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Brassicaceae/química , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , DNA (Citosina-5-)-Metiltransferase 1/genética , Humanos , Isotiocianatos/administração & dosagem , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Sulfóxidos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cancer Lett ; 457: 98-109, 2019 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-31100412

RESUMO

ATP-binding cassette (ABC) transporters mediate multidrug resistance and cancer stem cell properties in various model systems. Yet, their biological significance in cancers, especially in hepatocellular carcinoma (HCC), remains unclear. In this study, we investigated the function of ABCF1 in HCC and explored its potential as a therapeutic target. ABCF1 was highly expressed in fetal mouse livers but not in normal adult livers. ABCF1 expression was upregulated in HCCs. These results demonstrate that ABCF1 functions as a hepatic oncofetal protein. We further demonstrated elevated ABCF1 expression in HCC cells upon acquiring chemoresistance. Suppression of ABCF1 by siRNA sensitized both parental cells and chemoresistant cells to chemotherapeutic agents. Reversely, ABCF1 overexpression promoted chemoresistance and drug efflux. In addition, overexpression of ABCF1 enhanced migration, spheroid and colony formation and epithelial-mesenchymal transition (EMT) induction. RNA sequencing analysis revealed EMT inducers HIF1α/IL8 and Sox4 as potential mediators for the oncogenic effect of ABCF1 in HCC progression. Together, this study illustrates that ABCF1 is a novel potential therapeutic target for HCC treatment.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Carcinoma Hepatocelular/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos ICR , Camundongos Nus , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Int J Oncol ; 54(3): 1010-1020, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30569106

RESUMO

The Wnt signaling pathway is known to serve an important role in the control of cell migration. The present study analyzed the mechanisms underlying the in vitro modulation of the migration of nasopharyngeal carcinoma (NPC) cells by the CREB­binding protein/catenin antagonist and Wnt modulator ICG­001. The results revealed that ICG­001­mediated inhibition of tumor cell migration involved downregulated mRNA and protein expression of the Wnt target gene cluster of differentiation (CD)44. It was also demonstrated that ICG­001 downregulated the expression of CD44, and this effect was accompanied by restored expression of microRNA (miRNA)­150 in various NPC cell lines. Using a CD44 3'­untranslated region luciferase reporter assay, miR­150 was confirmed to be a novel CD44­targeting miRNA, which could directly target CD44 and subsequently regulate the migration of NPC cells. The present study provides further insight into the inhibition of tumor cell migration through the modulation of miRNA expression by the Wnt modulator ICG­001.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Movimento Celular/efeitos dos fármacos , Receptores de Hialuronatos/genética , MicroRNAs/genética , Carcinoma Nasofaríngeo/metabolismo , Pirimidinonas/farmacologia , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/antagonistas & inibidores , Receptores de Hialuronatos/metabolismo , Camundongos , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Via de Sinalização Wnt/efeitos dos fármacos
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