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1.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32641480

RESUMO

We previously reported that the cellular transcription factor hypoxia-inducible factor 1α (HIF-1α) binds a hypoxia response element (HRE) located within the promoter of Epstein-Barr virus's (EBV's) latent-lytic switch BZLF1 gene, Zp, inducing viral reactivation. In this study, EBV-infected cell lines derived from gastric cancers and Burkitt lymphomas were incubated with HIF-1α-stabilizing drugs: the iron chelator deferoxamine (Desferal [DFO]), a neddylation inhibitor (pevonedistat [MLN-4924]), and a prolyl hydroxylase inhibitor (roxadustat [FG-4592]). DFO and MLN-4924, but not FG-4592, induced accumulation of both lytic EBV proteins and phosphorylated p53 in cell lines that contain a wild-type p53 gene. FG-4592 also failed to activate transcription from Zp in a reporter assay despite inducing accumulation of HIF-1α and transcription from another HRE-containing promoter. Unexpectedly, DFO failed to induce EBV reactivation in cell lines that express mutant or no p53 or when p53 expression was knocked down with short hairpin RNAs (shRNAs). Likewise, HIF-1α failed to activate transcription from Zp when p53 was knocked out by CRISPR-Cas9. Importantly, DFO induced binding of p53 as well as HIF-1α to Zp in chromatin immunoprecipitation (ChIP) assays, but only when the HRE was present. Nutlin-3, a drug known to induce accumulation of phosphorylated p53, synergized with DFO and MLN-4924 in inducing EBV reactivation. Conversely, KU-55933, a drug that inhibits ataxia telangiectasia mutated, thereby preventing p53 phosphorylation, inhibited DFO-induced EBV reactivation. Lastly, activation of Zp transcription by DFO and MLN-4924 mapped to its HRE. Thus, we conclude that induction of BZLF1 gene expression by HIF-1α requires phosphorylated, wild-type p53 as a coactivator, with HIF-1α binding recruiting p53 to Zp.IMPORTANCE EBV, a human herpesvirus, is latently present in most nasopharyngeal carcinomas, Burkitt lymphomas, and some gastric cancers. To develop a lytic-induction therapy for treating patients with EBV-associated cancers, we need a way to efficiently reactivate EBV into lytic replication. EBV's BZLF1 gene product, Zta, usually controls this reactivation switch. We previously showed that HIF-1α binds the BZLF1 gene promoter, inducing Zta synthesis, and HIF-1α-stabilizing drugs can induce EBV reactivation. In this study, we determined which EBV-positive cell lines are reactivated by classes of HIF-1α-stabilizing drugs. We found, unexpectedly, that HIF-1α-stabilizing drugs only induce reactivation when they also induce accumulation of phosphorylated, wild-type p53. Fortunately, p53 phosphorylation can also be provided by drugs such as nutlin-3, leading to synergistic reactivation of EBV. These findings indicate that some HIF-1α-stabilizing drugs may be helpful as part of a lytic-induction therapy for treating patients with EBV-positive malignancies that contain wild-type p53.


Assuntos
Herpesvirus Humano 4/genética , Interações Hospedeiro-Patógeno/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Transativadores/genética , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Ciclopentanos/farmacologia , Desferroxamina/farmacologia , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Regulação da Expressão Gênica , Glicina/análogos & derivados , Glicina/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/crescimento & desenvolvimento , Herpesvirus Humano 4/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/agonistas , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Quelantes de Ferro/farmacologia , Isoquinolinas/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/virologia , Morfolinas/farmacologia , Piperazinas/farmacologia , Inibidores de Prolil-Hidrolase/farmacologia , Regiões Promotoras Genéticas , Ligação Proteica/efeitos dos fármacos , Pirimidinas/farmacologia , Pironas/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Elementos de Resposta , Transdução de Sinais , Transativadores/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Ativação Viral/efeitos dos fármacos
2.
Anal Biochem ; 629: 114212, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-33872579

RESUMO

In this study, the isothermal detection of a cervical cancer-associated long non-coding RNA (lncRNA), namely, lncRNA-ATB, was performed for the first time with high selectivity and sensitivity via a T7 RNA polymerase transcription-mediated amplification system combined with a graphene oxide (GO) fluorescence-based sensor. Specific lncRNA primers with the T7 promoter overhang were designed and further had with the efficient amplification ability of T7 RNA polymerase. This detection platform distinguished the target lncRNA-ATB from other lncRNAs. In addition, the super fluorescence quenching ability of GO resulted in the development of a switch on/off fluorescence sensor. The resulting platform was able to detect target lncRNAs from samples of cervical cancer cell lines (HeLa) and human sera with high selectivity and a low detection limit of 1.96 pg. Therefore, the assay developed in this study demonstrated a high potential as an alternative tool for lncRNA quantification in clinical diagnosis.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , RNA Longo não Codificante/análise , Neoplasias do Colo do Útero/diagnóstico , Proteínas Virais/metabolismo , Sequência de Bases , Técnicas Biossensoriais , Linhagem Celular Tumoral , Feminino , Grafite/química , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Propriedades de Superfície
3.
PLoS Pathog ; 13(6): e1006404, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28617871

RESUMO

When confronted with poor oxygenation, cells adapt by activating survival signaling pathways, including the oxygen-sensitive transcriptional regulators called hypoxia-inducible factor alphas (HIF-αs). We report here that HIF-1α also regulates the life cycle of Epstein-Barr virus (EBV). Incubation of EBV-positive gastric carcinoma AGS-Akata and SNU-719 and Burkitt lymphoma Sal and KemIII cell lines with a prolyl hydroxylase inhibitor, L-mimosine or deferoxamine, or the NEDDylation inhibitor MLN4924 promoted rapid and sustained accumulation of both HIF-1α and lytic EBV antigens. ShRNA knockdown of HIF-1α significantly reduced deferoxamine-mediated lytic reactivation. HIF-1α directly bound the promoter of the EBV primary latent-lytic switch BZLF1 gene, Zp, activating transcription via a consensus hypoxia-response element (HRE) located at nt -83 through -76 relative to the transcription initiation site. HIF-1α did not activate transcription from the other EBV immediate-early gene, BRLF1. Importantly, expression of HIF-1α induced EBV lytic-gene expression in cells harboring wild-type EBV, but not in cells infected with variants containing base-pair substitution mutations within this HRE. Human oral keratinocyte (NOK) and gingival epithelial (hGET) cells induced to differentiate by incubation with either methyl cellulose or growth in organotypic culture accumulated both HIF-1α and Blimp-1α, another cellular factor implicated in lytic reactivation. HIF-1α activity also accumulated along with Blimp-1α during B-cell differentiation into plasma cells. Furthermore, most BZLF1-expressing cells observed in lymphomas induced by EBV in NSG mice with a humanized immune system were located distal to blood vessels in hypoxic regions of the tumors. Thus, we conclude that HIF-1α plays central roles in both EBV's natural life cycle and EBV-associated tumorigenesis. We propose that drugs that induce HIF-1α protein accumulation are good candidates for development of a lytic-induction therapy for treating some EBV-associated malignancies.


Assuntos
Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linfoma/metabolismo , Transativadores/genética , Animais , Linfócitos B/metabolismo , Linfócitos B/virologia , Carcinogênese , Linhagem Celular Tumoral , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Linfoma/genética , Linfoma/virologia , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , Transativadores/metabolismo , Ativação Viral
4.
Anal Biochem ; 577: 89-97, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31029676

RESUMO

In this study, we developed a simple multiplex miRNA detection platform based on rolling circle amplification and the fluorescence quenching property of reduced graphene oxide. The detection platform could be applied on a microfluidics chip with a mobile system controller to eliminate contamination and to facilitate potential use in remote areas. As a proof of concept, two fluorescence-labeled ssDNA tags were used for detection of miR-29a and miR-144*, two miRNAs that are highly expressed in the blood circulation of some patients with cancer or tuberculosis. The circular ssDNA probes in this study were designed to have an advantage over padlock probes as they can be prepared in advance. Our multiplex miRNA detection platform exhibited high sensitivity and selectivity, with a limit of detection of 0.05 pmol. In addition, our platform could detect target miRNAs from the total miRNA population extracted from human serum or a cancer cell line. These results indicated that our miRNA sensor has the potential to provide simple and high throughput miRNA analysis for disease diagnosis and prognosis.


Assuntos
MicroRNAs/análise , Neoplasias/diagnóstico , Tuberculose/diagnóstico , DNA de Cadeia Simples/química , Células HeLa , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Estudo de Prova de Conceito , Espectrometria de Fluorescência/métodos
5.
Analyst ; 144(14): 4180-4187, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31123738

RESUMO

MicroRNAs (miRNAs) play important roles in gene regulation and have been reported as biomarkers in cancer diagnosis. Herein, we develop an isothermal miRNA detection platform based on the highly efficient, multiple primer-mediated rolling circle amplification method coupled with a graphene oxide-based fluorescence (MPRCA-GO) assay, using lung cancer-associated miRNAs (miR-21 and miR-210) and a reference miRNA (miR-16) as model targets. The combination of the designed ssDNA probe and T4 RNA ligase (T4 Rnl2) used in the MPRCA-GO assay allowed for single-base mismatch discrimination. In addition, the superfluorescence quenching ability of GO allowed for rapid fluorescence detection. The developed platform had a limit of detection as low as 0.87 fM and could detect target miRNAs in cancer cell lines and human serums. Therefore, the MPRCA-GO sensor has the potential for single nucleotide polymorphism (SNP) analysis and applications in clinical diagnostics.


Assuntos
Biomarcadores Tumorais/sangue , Grafite/química , MicroRNAs/sangue , Bacteriófago T4/enzimologia , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Sondas de DNA/genética , DNA de Cadeia Simples/genética , Fluorescência , Humanos , Limite de Detecção , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico , RNA Ligase (ATP)/química , Espectrometria de Fluorescência/métodos , Proteínas Virais/química
6.
Biochem Biophys Res Commun ; 500(4): 866-872, 2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29705700

RESUMO

Glycosmis parva is a small shrub found in Thailand. Ethyl acetate (EtOAc) extract from its leaves has been shown to exert anticancer effects in vitro; however, the compound responsible for this activity has not been isolated and characterized. In this study, we demonstrate that arborinine, a major acridone alkaloid in the EtOAc fraction, decreased proliferation and was strongly cytotoxic to HeLa cervical cancer cells without significantly affecting normal cells. The compound also inhibited tumor spheroid growth much more potently than chemotherapeutic drugs bleomycin, gemcitabine, and cisplatin. In addition, unlike cisplatin, arborinine activated caspase-dependent apoptosis without inducing DNA damage response. We further show that arborinine strongly suppressed cancer cell migration by downregulating expression of key regulators of epithelial-mesenchymal transition. Taken together, our data provide important insights into the molecular mechanism of arborinine's anticancer activity, supporting its potential use for treating cervical cancer.


Assuntos
Acridinas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Rutaceae/química , Acridinas/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Bleomicina/farmacologia , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Derme/citologia , Derme/efeitos dos fármacos , Derme/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células HeLa , Humanos , Extratos Vegetais/química , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo , Gencitabina
7.
J Virol ; 88(9): 4811-27, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24522918

RESUMO

UNLABELLED: Ikaros is a zinc finger DNA-binding protein that regulates chromatin remodeling and the expression of genes involved in the cell cycle, apoptosis, and Notch signaling. It is a master regulator of lymphocyte differentiation and functions as a tumor suppressor in acute lymphoblastic leukemia. Nevertheless, no previous reports described effects of Ikaros on the life cycle of any human lymphotropic virus. Here, we demonstrate that full-length Ikaros (IK-1) functions as a major factor in the maintenance of viral latency in Epstein-Barr virus (EBV)-positive Burkitt's lymphoma Sal and MutuI cell lines. Either silencing of Ikaros expression by small hairpin RNA (shRNA) knockdown or ectopic expression of a non-DNA-binding isoform induced lytic gene expression. These effects synergized with other lytic inducers of EBV, including transforming growth factor ß (TGF-ß) and the hypoxia mimic desferrioxamine. Data from chromatin immunoprecipitation (ChIP)-quantitative PCR (qPCR) and ChIP-sequencing (ChIP-seq) analyses indicated that Ikaros did not bind to either of the EBV immediate early genes BZLF1 and BRLF1. Rather, Ikaros affected the expression of Oct-2 and Bcl-6, other transcription factors that directly inhibit EBV reactivation and plasma cell differentiation, respectively. IK-1 also complexed with the EBV immediate early R protein in coimmunoprecipitation assays and partially colocalized with R within cells. The presence of R alleviated IK-1-mediated transcriptional repression, with IK-1 then cooperating with Z and R to enhance lytic gene expression. Thus, we conclude that Ikaros plays distinct roles at different stages of EBV's life cycle: it contributes to maintaining latency via indirect mechanisms, and it may also synergize with Z and R to enhance lytic replication through direct association with R and/or R-induced alterations in Ikaros' functional activities via cellular signaling pathways. IMPORTANCE: This is the first report showing that the cellular protein Ikaros, a known master regulator of hematopoiesis and critical tumor suppressor in acute lymphoblastic leukemia, also plays important roles in the life cycle of Epstein-Barr virus in B cells.


Assuntos
Linfócitos B/virologia , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Fator de Transcrição Ikaros/metabolismo , Latência Viral , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Técnicas de Silenciamento de Genes , Humanos , Ligação Proteica
8.
J Virol ; 85(15): 7836-48, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21593157

RESUMO

Transforming growth factor ß (TGF-ß) physiologically induces Epstein-Barr virus (EBV) lytic infection by activating the expression of EBV's latent-lytic switch BZLF1 gene. Liang et al. (J. Biol. Chem. 277:23345-23357, 2002) previously identified a Smad-binding element (SBE) within the BZLF1 promoter, Zp; however, it accounts for only 20 to 30% of TGF-ß-mediated activation of transcription from Zp. Here, we identified additional factors responsible for the rest of this activation. The incubation of EBV-positive MutuI cells with a TGF-ß neutralizing antibody or inhibitors of the TGF-ß type I receptor (TßRI) or Smad3 eliminated the TGF-ß-induced reactivation of EBV. The coexpression of Smad2, Smad3, and Smad4 together with a constitutively active form of TßRI induced 15- to 25-fold transcription from Zp in gastric carcinoma AGS cells. By electrophoretic mobility shift assays, we identified four additional Smad-binding elements, named SBE2 to SBE5. Substitution mutations in individual SBEs reduced Smad-mediated activation of Zp by 20 to 60%; together, these mutations essentially eliminated it. Chromatin immunoprecipitation assays confirmed that Smad4 newly bound the Zp region of the EBV genome following the incubation of MutuI cells with TGF-ß. SBE2 overlaps the ZEB-binding ZV silencing element of Zp. Depending upon posttranslational modifications, Smad4 either competed with ZEB1 for binding or formed a complex with ZEB1 on the Zp ZV element in a cell-free assay system. In transiently transfected cells, exogenously expressed ZEB1 inhibited Smad-mediated transcriptional activation from Zp. We conclude that TGF-ß induces EBV lytic reactivation via the canonical Smad pathway by activating BZLF1 gene expression through multiple SBEs acting in concert.


Assuntos
Herpesvirus Humano 4/fisiologia , Proteínas Smad/fisiologia , Transativadores/genética , Fator de Crescimento Transformador beta/fisiologia , Ativação Viral , Latência Viral , Sequência de Bases , Linhagem Celular Tumoral , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida
9.
J Virol ; 85(10): 5081-90, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21389123

RESUMO

The Epstein-Barr virus (EBV) BZLF1 gene encodes the immediate-early (IE) protein Zta, which plays a central role in regulating the switch between viral latency and lytic replication. A silencing element, ZIIR, is located between the ZID and ZII positive regulatory elements in the BZLF1 promoter Zp. We report here the phenotypes of variants of EBV strain B95.8 containing base substitution mutations in this ZIIR element. HEK293 cells infected with ZIIR mutant (ZIIRmt) virus produced at least 20-fold more viral IE Zta and Rta and early (E) EAD protein than did cells infected with the parental wild-type (WT) virus, leading to viral DNA replication and production of infectious virus. However, ZIIR mutant virus was 1/10 as efficient as WT virus in establishing proliferating B-cell clones following infection of human primary blood B cells. The ZIIRmt-infected lymphoblastoid cell lines (LCLs) that did grow out exhibited a phenotype similar to the one observed in 293 cells, including marked overproduction of IE and E gene products relative to WT-infected LCLs and lytic replication of the viral genome. Incubation of the ZIIRmt-infected LCLs with the chemical inducer 12-O-tetradecanoyl-phorbol-13-acetate (TPA) led to much greater activation of Zp than did the same treatment of WT- or ZVmt-infected LCLs. Furthermore, a protein kinase C (PKC) inhibitor, bis-indolylmaleimide, eliminated this activation by TPA. Thus, we conclude that ZIIR is a potent silencing element of Zp; it plays a key role in establishment and maintenance of EBV latency by inhibiting activation of Zp through the PKC signal transduction pathway.


Assuntos
Herpesvirus Humano 4/fisiologia , Regiões Promotoras Genéticas , Transativadores/genética , Latência Viral , Linfócitos B/virologia , Linhagem Celular , Herpesvirus Humano 4/genética , Humanos , Mutagênese Sítio-Dirigida , Transativadores/metabolismo
10.
Biomed Pharmacother ; 145: 112461, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34839253

RESUMO

Skin aging is accompanied by an increase in the number of senescent cells, resulting in various pathological outcomes. These include inflammation, impaired barrier function, and susceptibility to skin disorders such as cancer. Kaempferia parviflora (Thai black ginger), a medicinal plant native to Thailand, has been shown to counteract inflammation, cancer, and senescence. This study demonstrates that polymethoxyflavones (5,7-dimethoxyflavone, 5,7,4'-trimethoxyflavone, and 3,5,7,3',4'-pentamethoxyflavone) purified from K. parviflora rhizomes suppressed cellular senescence, reactive oxygen species, and the senescence-associated secretory phenotype in primary human dermal fibroblasts. In addition, they increased tropocollagen synthesis and alleviated free radical-induced cellular and mitochondrial damage. Moreover, the compounds mitigated chronological aging in a human ex vivo skin model by attenuating senescence and restoring expression of essential components of the extracellular matrix, including collagen type I, fibrillin-1, and hyaluronic acid. Finally, we report that polymethoxyflavones enhanced epidermal thickness and epidermal-dermal stability, while blocking age-related inflammation in skin explants. Our findings support the use of polymethoxyflavones from K. parviflora as natural anti-aging agents, highlighting their potential as active ingredients in cosmeceutical and nutraceutical products.


Assuntos
Colágeno Tipo I/metabolismo , Matriz Extracelular , Flavonoides/farmacologia , Ácido Hialurônico/metabolismo , Envelhecimento da Pele , Pele , Zingiberaceae , Linhagem Celular , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/fisiologia , Fibrilina-1/metabolismo , Fibroblastos/metabolismo , Flavonas/farmacologia , Gerociência , Humanos , Rizoma , Pele/efeitos dos fármacos , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/fisiologia , Tailândia
11.
J Virol ; 84(19): 10329-43, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20668090

RESUMO

We previously showed that the cellular proteins ZEB1 and ZEB2/SIP1 both play key roles in regulating the latent-lytic switch of Epstein-Barr Virus (EBV) by repressing BZLF1 gene expression. We investigated here the effects of cellular microRNA (miRNA) 200 (miR200) family members on the EBV infection status of cells. We show that miR200b and miR429, but not miR200a, can induce EBV-positive cells into lytic replication by downregulating expression of ZEB1 and ZEB2, leading to production of infectious virus. The levels of miR200 family members in EBV-infected cells strongly negatively correlated with the levels of the ZEBs (e.g., -0.89 [P < 0.001] for miR429 versus ZEB1) and positively correlated with the degree of EBV lytic gene expression (e.g., 0.73 [P < 0.01] for miR429 versus BZLF1). The addition of either miR200b or miR429 to EBV-positive cells led to EBV lytic reactivation in a ZEB-dependent manner; inhibition of these miRNAs led to decreased EBV lytic gene expression. The degree of latent infection by an EBV mutant defective in the primary ZEB-binding site of the EBV BZLF1 promoter was not affected by the addition of these miRNAs. Furthermore, EBV infection of primary blood B cells led to downregulation of these miRNAs and upregulation of ZEB levels. Thus, we conclude that miRNAs 200b and 429 are key regulators via their effects on expression of ZEB1 and ZEB2 of the switch between latent and lytic infection by EBV and, therefore, potential targets for development of new lytic induction therapeutics with which to treat patients with EBV-associated malignancies.


Assuntos
Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , MicroRNAs/genética , Sequência de Bases , Linhagem Celular , DNA Viral/genética , Regulação para Baixo , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Genes Virais , Herpesvirus Humano 4/patogenicidade , Proteínas de Homeodomínio/fisiologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Modelos Biológicos , Regiões Promotoras Genéticas , Proteínas Repressoras/fisiologia , Transativadores/genética , Fatores de Transcrição/fisiologia , Latência Viral/genética , Latência Viral/fisiologia , Replicação Viral/genética , Replicação Viral/fisiologia , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de Zinco
12.
Exp Biol Med (Maywood) ; 246(6): 654-666, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33307803

RESUMO

Circulating cell-free DNA (cfDNA) has attracted attention as a non-invasive biomarker for diagnosing and monitoring various cancers. Given that human papillomavirus (HPV) DNA integration and overexpression of E6/E7 oncogenes are pivotal events for carcinogenesis, we sought to determine if HPV E7 cfDNA could serve as a specific biomarker for cervical cancer detection. We applied droplet digital PCR (ddPCR) to quantify HPV16/18 E7 cfDNA from the serum of patients with cervical cancer, cervical intraepithelial neoplasia, and controls. HPV16/18 E7 cfDNA was highly specific for cervical cancer, displaying 30.77% sensitivity, 100% specificity, and an area under the curve of 0.65. Furthermore, we developed a sensitive isothermal detection of HPV16/18 E7 and the PIK3CA WT reference gene based on recombinase polymerase amplification combined with a lateral flow strip (RPA-LF). The assay took less than 30 min and the detection limit was 5-10 copies. RPA-LF exhibited 100% sensitivity and 88.24% specificity towards HPV16/18 E7 cfDNA in clinical samples. The agreement between RPA-LF and ddPCR was 83.33% (κ = 0.67) for HPV16 E7 and 100% (κ = 1.0) for HPV18 E7, indicating a good correlation between both tests. Therefore, we conclude that HPV E7 cfDNA represents a potential tumor marker with excellent specificity and moderate sensitivity for minimally invasive cervical cancer monitoring. Moreover, the RPA-LF assay provides an affordable, rapid, and ultrasensitive tool for detecting HPV cfDNA in resource-limited settings.


Assuntos
Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , DNA Viral/genética , Proteínas de Ligação a DNA/sangue , Proteínas Oncogênicas Virais/sangue , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/sangue , Neoplasias do Colo do Útero/virologia , Adulto , Estudos de Casos e Controles , Classe I de Fosfatidilinositol 3-Quinases/genética , DNA Viral/sangue , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Reação em Cadeia da Polimerase , Curva ROC , Neoplasias do Colo do Útero/diagnóstico
13.
Colloids Surf B Biointerfaces ; 197: 111369, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33032178

RESUMO

Cordycepin, a derivative of the nucleotide adenosine, has displayed several pharmacological activities including enhanced apoptosis and cancer cells inhibition. However, oral administration of cordycepin has limited practical use due to its poor bioavailability in the intestine. Herein, we developed and demonstrated a hybrid nanocarrier system in the form of biloniosome-core/chitosan-shell hybrid nanocarriers (HNCs) in order to improve the bio-characteristics of cordycepin. In this study, HNCs were prepared by using a solvent (ethanol) injection method involving cordycepin as the biloniosome core and mucoadhesive chitosan biopolymer as a coating shell. Our results showed that the cordycepin-loaded HNCs were positively charged with enhanced mucoadhesive characteristics and highly stable in gastric fluid. The increased permeability of cordycepin-loaded HNCs compared with standard cordycepin was confirmed by in vitro intestinal permeation study across the human intestinal barrier. In addition, we demonstrated that the cordycepin-loaded HNCs are able to release their components in an active form resulting in enhanced anti-cancer activity in two-dimensional (2D) cell cultures as well as in three-dimensional (3D) multi-cellular spheroids of colon cancer cells. Further, quantitative real time PCR analysis of apoptotic gene expression revealed that cordycepin HNCs can induce apoptosis in cancer cells by negatively regulating the expression of B-cell lymphoma-extra large (BCL-XL). I Overall our results showed that the hybrid nanocarrier systems represent a promising strategy for improving the bio-characteristics of cordycepin which can be considered as a potential anti-cancer agent for colorectal cancer chemotherapy.


Assuntos
Quitosana , Administração Oral , Apoptose , Desoxiadenosinas , Humanos
14.
Biochim Biophys Acta ; 1780(7-8): 989-94, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18439431

RESUMO

The two-component protease NS2B-NS3 of dengue virus mediates proteolytic processing of the polyprotein precursor and therefore represents a target for the development of antiviral drugs. The amino acid sequences of the NS3 serine protease and the NS2B cofactor exhibit relatively low degrees of conservation among the 4 serotypes thus suggesting that differences in enzyme activity exist which could modulate their susceptibility to future protease inhibitors. In this study we have addressed the question of functional similarity among the NS2B(H)-NS3pro proteases from 4 dengue virus serotypes by employing a uniform approach to clone, purify and assay proteolytic activity of these enzymes. Significant differences were observed for patterns of protein formation and expression levels in the E. coli host. Renaturation of the NS2B(H)-NS3pro precursors from dengue virus serotypes 2, 3 and 4 mediated by artificial chaperone-assisted refolding yielded enzymatically active proteases, whereas the enzyme from serotype 1 was obtained as soluble protein. Kinetic experiments using the GRR-amc substrate revealed comparable K(m) values while k(cat) values as obtained by active-site titration experiments displayed minor variations. Denaturation experiments demonstrated significant differences in half-life of the NS3 proteases from serotypes 2, 3 and 4 at 50 degrees C, whereas pH optima for all 4 enzymes were comparable.


Assuntos
Vírus da Dengue/enzimologia , Serina Endopeptidases/metabolismo , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Vírus da Dengue/classificação , Estabilidade Enzimática , Escherichia coli/genética , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Dados de Sequência Molecular , Mutação , Desnaturação Proteica , Renaturação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Serina Endopeptidases/análise , Serina Endopeptidases/química , Serina Endopeptidases/genética , Sorotipagem/classificação , Proteínas não Estruturais Virais/análise , Proteínas não Estruturais Virais/genética
15.
Biomolecules ; 9(9)2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527550

RESUMO

Crinumasiaticum is a perennial herb widely distributed in many warmer regions, including Thailand, and is well-known for its medicinal and ornamental values. Crinum alkaloids contain numerous compounds, such as crinamine. Even though its mechanism of action is still unknown, crinamine was previously shown to possess anticancer activity. In this study, we demonstrate that crinamine was more cytotoxic to cervical cancer cells than normal cells. It also inhibited anchorage-independent tumor spheroid growth more effectively than existing chemotherapeutic drugs carboplatin and 5-fluorouracil or the CDK9 inhibitor FIT-039. Additionally, unlike cisplatin, crinamine induced apoptosis without promoting DNA double-strand breaks. It suppressed cervical cancer cell migration by inhibiting the expression of positive regulators of epithelial-mesenchymal transition SNAI1 and VIM. Importantly, crinamine also exerted anti-angiogenic activities by inhibiting secretion of VEGF-A protein in cervical cancer cells and blood vessel development in zebrafish embryos. Gene expression analysis revealed that its mechanism of action might be attributed, in part, to downregulation of cancer-related genes, such as AKT1, BCL2L1, CCND1, CDK4, PLK1, and RHOA. Our findings provide a first insight into crinamine's anticancer activity, highlighting its potential use as an alternative bioactive compound for cervical cancer chemoprevention and therapy.


Assuntos
Alcaloides de Amaryllidaceae/administração & dosagem , Inibidores da Angiogênese/administração & dosagem , Crinum/química , Fatores de Transcrição da Família Snail/metabolismo , Neoplasias do Colo do Útero/metabolismo , Vimentina/metabolismo , Alcaloides de Amaryllidaceae/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Carboplatina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Embrião não Mamífero/irrigação sanguínea , Embrião não Mamífero/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Extratos Vegetais/química , Piridinas/farmacologia , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/tratamento farmacológico , Peixe-Zebra/embriologia
16.
FEBS Open Bio ; 8(11): 1844-1854, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30410863

RESUMO

Circulating lncRNAs have attracted considerable attention as potential noninvasive biomarkers for diagnosing cancers. RT-qPCR is the canonical technique for detecting circulating RNA and depends largely on stable reference genes for data normalization. However, no systematic evaluation of reference genes for serum lncRNA has been reported for cervical cancer. Here, we profiled and validated lncRNA expression from serum of cervical cancer patients and controls using microarrays and RT-qPCR. We identified lncRNA RP11-204K16.1, XLOC_012542, and U6 small nuclear RNA as the most stable reference genes based on geNorm, NormFinder, BestKeeper, delta Ct, and RefFinder. These genes were suitable also for samples from different age groups or with hemolysis. Additionally, we discovered lncRNA AC017078.1 and XLOC_011152 as candidate biomarkers, whose expression was down-regulated in cervical cancer. Our findings could aid research on circulating lncRNA and the discovery of blood-based biomarkers for cervical cancer diagnosis.

17.
Theriogenology ; 108: 167-175, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29223654

RESUMO

The overpopulation of free-roaming companion animals has become the global crisis. The development and application of a suitable, effective, non-surgical approach for animal sterilization would have an enormous advantage over the current surgical method. The main purpose of this study was to develop and evaluate a novel nanomedicine-based chemosterilant for non-surgical castration of male companion animals. In this study, we first sought to investigate the testicular toxicity of different apoptosis-inducing agents. We next synthesized and characterized nano-sized particles which encapsulated the most potent testicular toxicants and evaluated in vitro sterilant properties. Our result showed that doxorubicin exhibited the highest cytotoxic activity against mouse spermatogenic cells. We therefore synthesized and characterized doxorubicin-encapsulated nanoemulsion. The negatively charged particle of doxorubicin-encapsulated nanoemulsion exhibited the anti-proliferative activity towards spermatogetic cells. Apoptosis studies revealed activation of Caspases 3 and 7 as well as annexin V expression. In addition, doxorubicin-encapsulated nanoemulsion exhibited anti-inflammatory activity in lipopolysaccharide-stimulated macrophages. Cell death was observed following treatment of isolated and cultured rat seminiferous tubules with doxorubicin-encapsulated nanoemulsion. In conclusion, nanoemulsion can be a potential carrier for prolonged release and to enhance activity of doxorubicin that may have utility in non-surgical castration of male animals.


Assuntos
Esterilizantes Químicos/administração & dosagem , Doxorrubicina/administração & dosagem , Animais de Estimação , Esterilização Reprodutiva/veterinária , Bem-Estar do Animal , Animais , Apoptose/efeitos dos fármacos , Gatos , Cães , Doxorrubicina/uso terapêutico , Células Germinativas/efeitos dos fármacos , Masculino , Camundongos , Nanomedicina/métodos , Ratos , Túbulos Seminíferos/efeitos dos fármacos , Esterilização Reprodutiva/métodos
18.
Exp Biol Med (Maywood) ; 242(2): 184-193, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27633578

RESUMO

Long non-coding RNA H19 is aberrantly expressed in multiple malignancies and its expression levels correlate with recurrence, metastasis, and patient survival. Despite numerous reports documenting the role of H19 in carcinogenesis, its contribution to cervical cancer development is still largely unknown. In this study, I observed that H19 expression was elevated in cervical cancer cell lines and could be detected in extracellular vesicles in the culture medium. In addition, I demonstrated, by overexpression and knockdown experiments, that H19 promoted cell proliferation and multicellular tumor spheroid formation without significantly affecting apoptosis and cell migration. Finally, treatment with transforming growth factor beta and hypoxia-mimetic CoCl2 could modulate H19 levels in a cell line-specific manner. These findings indicate that H19 promotes both anchorage-specific and -independent growth of cervical cancer cell lines and may serve as a potential target for cancer diagnosis and therapy.


Assuntos
Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Carcinogênese/genética , Adesão Celular/genética , Cobalto/farmacologia , Vesículas Extracelulares/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Interferência de RNA , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/genética , Esferoides Celulares/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/patologia
19.
Colloids Surf B Biointerfaces ; 149: 301-311, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780087

RESUMO

A nanostructure lipid carrier (NLC) composed of solid, and liquid lipid as a core has been developed as a delivery system for hydrophobic drug molecules. The aim of this research was to fabricate an oleoyl-quaternized-chitosan (CS)-coated NLC, where the mucoadhesive property of nanoparticles is enhanced for more efficient drug delivery. NLC loaded with alpha-mangostin (AP), a model hydrophobic drug, were fabricated using a high pressure homogenization process and subsequently coated with CS. The fabricated nanoparticles showed particle sizes in the range of 200-400nm, with low polydispersity, high physical stability and excellent encapsulation efficiency (EE>90%). Additionally, in vitro viability, cytotoxicity and ability of NLC and CS-NLC to affect apoptosis in carcinoma Caco-2 cells were determined using the Triplex assay. Gene expressiom analysis were performed using quantitative reverse transcription Polymerase Chain Reaction (RT-qPCR). Moreover, in vivo toxicological testing of NLCs was conducted in zebrafish embryos. Results indicated that CS-NLC provieded high cytotoxicity than NLC itself. In the case of AP loaded nanoparticles, NLC loaded with AP (AP-NLC), and CS-NLC loaded with AP (CS-AP-NLC) exhibited higher cytotoxicity to Caco-2 over Hela cells. These results indicate that CS-NLC shows enhanced cellular uptake but increased cytotoxicity characteristics over NLC and therefore careful optimization of dosage and loading levels in CS-NLC is needed to allow cancer cell targeting, and for exploiting the potential of these systems in cancer therapy.


Assuntos
Quitosana/análogos & derivados , Portadores de Fármacos , Nanopartículas/química , Inibidores de Proteínas Quinases/farmacologia , Xantonas/farmacologia , Apoptose/efeitos dos fármacos , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/ultraestrutura , Tamanho da Partícula , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Propriedades de Superfície , Xantonas/química , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
20.
Exp Biol Med (Maywood) ; 241(2): 166-76, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26290139

RESUMO

Tetragonula laeviceps cerumen was sequentially extracted with 80% (v/v) methanol, dichloromethane, and hexane and also in the reverse order. By the MTT assay and the respective 50% inhibition concentration value, the most active fraction was further purified to apparent homogeneity by bioassay-guided silica gel column chromatography. α-Mangostin was identified by high-resolution electrospray ionization mass spectrometry and nuclear magnetic resonance analyses. It had a potent cytotoxicity against the BT474, Chago, Hep-G2, KATO-III, and SW620 cell lines (IC50 values of 1.22 ± 0.03, 2.25 ± 0.20, 0.94 ± 0.01, 0.88 ± 0.16, and 1.50 ± 0.39 µmol/L, respectively). The in vitro cytotoxicity of α-mangostin against the five human cancer cell lines and primary fibroblasts was further characterized by real-time impedance-based analysis. Interestingly, α-mangostin was more cytotoxic against the cancer-derived cell lines than against the primary fibroblasts. Later, the migration assay was performed by continuously measuring the attachment of cells to the plate electrodes at the bottom of the transwell membrane. The combined caspase-3 and -7 activities were assayed by the Caspase-Glo® 3/7 kit. It showed that the cytotoxic mechanism involved caspase-independent apoptosis, while at low (non-toxic) concentrations α-mangostin did not significantly alter cell migration. Furthermore, the in vivo cytotoxicity and angiogenesis were determined by alkaline phosphatase staining in zebrafish embryos along with monitoring changes in the transcript expression level of two genes involved in angiogenesis (vegfaa and vegfr2) by quantitative real-time reverse transcriptase- polymerase chain reaction. It was found that the in vivo cytotoxicity of α-mangostin against zebrafish embryos had a 50% lethal concentration of 9.4 µM, but no anti-angiogenic properties were observed in zebrafish embryos at 9 and 12 µM even though it downregulated the expression of vegfaa and vegfr2 transcripts. Thus, α-mangostin is a major active compound with a potential anticancer activity in T. laeviceps cerumen in Thailand.


Assuntos
Antineoplásicos/metabolismo , Abelhas/química , Cerume/química , Xantonas/metabolismo , Animais , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Formazans/análise , Perfilação da Expressão Gênica , Humanos , Técnicas In Vitro , Concentração Inibidora 50 , Masculino , Sais de Tetrazólio/análise , Tailândia , Xantonas/isolamento & purificação , Peixe-Zebra
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