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1.
BMC Genomics ; 25(1): 498, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773419

RESUMO

BACKGROUND: The hair follicle development process is regulated by sophisticated genes and signaling networks, and the hair grows from the hair follicle. The Tianzhu white yak population exhibits differences in hair length, especially on the forehead and shoulder region. However, the genetic mechanism is still unclear. Isoform sequencing (Iso-seq) technology with advantages in long reads sequencing. Hence, we combined the Iso-seq and RNA-seq methods to investigate the transcript complexity and difference between long-haired yak (LHY) and normal-haired yak (NHY). RESULTS: The hair length measurement result showed a significant difference between LHY and NHY on the forehead and the shoulder (P-value < 0.001). The skin samples from the forehead and the shoulder of LHY and NHY were pooled for isoform sequencing (Iso-seq). We obtained numerous long transcripts, including novel isoforms, long non-coding RNA, alternative splicing events, and alternative polyadenylation events. Combined with RNA-seq data, we performed differential isoforms (DEIs) analysis between LHY and NHY. We found that some hair follicle and skin development-related DEIs, like BMP4, KRT2, IGF2R, and COL1A2 in the forehead skin; BMP1, KRT1, FGF5, COL2A1, and IGFBP5 in the shoulder skin. Enrichment analysis revealed that DEIs in both two comparable groups significantly participated in skin and hair follicle development-related pathways, like ECM-receptor interaction, focal adhesion, and PI3K-Akt signaling pathways. The results indicated that the hair follicle development of Tianzhu white yak may influence the hair length difference. Besides, the protein-protein interaction (PPI) network of DEIs showed COL2A1 and COL3A1 exhibited a high degree of centrality, and these two genes were suggested as potential candidates for the hair length growth of Tianzhu white yak. CONCLUSIONS: The results provided a comprehensive analysis of the transcriptome complexity and identified differential transcripts that enhance our understanding of the molecular mechanisms underlying the variation in hair length growth in Tianzhu white yak.


Assuntos
Cabelo , Isoformas de Proteínas , RNA-Seq , Pele , Transcriptoma , Animais , Bovinos/genética , Pele/metabolismo , Cabelo/metabolismo , Cabelo/crescimento & desenvolvimento , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Folículo Piloso/metabolismo , Folículo Piloso/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Processamento Alternativo , Análise de Sequência de RNA
2.
Cancer Treat Res ; 177: 23-62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30523620

RESUMO

Discovered in 1994, Kaposi's sarcoma-associated herpesvirus (KSHV) has been associated with four human malignancies including Kaposi's sarcoma, primary effusion lymphoma, a subset of multicentric Castleman's disease, and KSHV inflammatory cytokine syndrome. These malignancies mostly occur in immunocompromised patients including patients with acquired immunodeficiency syndrome and often cause significant mortality because of the lack of effective therapies. Significant progresses have been made to understand the molecular basis of KSHV infection and KSHV-induced oncogenesis in the last two decades. This chapter provides an update on the recent advancements focusing on the molecular events of KSHV primary infection, the mechanisms regulating KSHV life cycle, innate and adaptive immunity, mechanism of KSHV-induced tumorigenesis and inflammation, and metabolic reprogramming in KSHV infection and KSHV-transformed cells.


Assuntos
Síndrome da Imunodeficiência Adquirida/virologia , Infecções por Herpesviridae/genética , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/imunologia , Neoplasias/virologia , Síndrome da Imunodeficiência Adquirida/complicações , Carcinogênese/genética , Carcinogênese/imunologia , Hiperplasia do Linfonodo Gigante/fisiopatologia , Hiperplasia do Linfonodo Gigante/virologia , Coinfecção/virologia , Citocinas/imunologia , Infecções por HIV/complicações , Infecções por HIV/virologia , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/fisiologia , Humanos , Hospedeiro Imunocomprometido , Inflamação/imunologia , Inflamação/fisiopatologia , Inflamação/virologia , Linfoma de Efusão Primária/fisiopatologia , Linfoma de Efusão Primária/virologia , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/fisiopatologia , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/virologia , Síndrome , Viremia/imunologia , Viremia/fisiopatologia , Viremia/virologia
3.
PLoS Pathog ; 12(5): e1005648, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27187079

RESUMO

Aerobic glycolysis is essential for supporting the fast growth of a variety of cancers. However, its role in the survival of cancer cells under stress conditions is unclear. We have previously reported an efficient model of gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV)-induced cellular transformation of rat primary mesenchymal stem cells. KSHV-transformed cells efficiently induce tumors in nude mice with pathological features reminiscent of Kaposi's sarcoma tumors. Here, we report that KSHV promotes cell survival and cellular transformation by suppressing aerobic glycolysis and oxidative phosphorylation under nutrient stress. Specifically, KSHV microRNAs and vFLIP suppress glycolysis by activating the NF-κB pathway to downregulate glucose transporters GLUT1 and GLUT3. While overexpression of the transporters rescues the glycolytic activity, it induces apoptosis and reduces colony formation efficiency in softagar under glucose deprivation. Mechanistically, GLUT1 and GLUT3 inhibit constitutive activation of the AKT and NF-κB pro-survival pathways. Strikingly, GLUT1 and GLUT3 are significantly downregulated in KSHV-infected cells in human KS tumors. Furthermore, we have detected reduced levels of aerobic glycolysis in several KSHV-infected primary effusion lymphoma cell lines compared to a Burkitt's lymphoma cell line BJAB, and KSHV infection of BJAB cells reduced aerobic glycolysis. These results reveal a novel mechanism by which an oncogenic virus regulates a key metabolic pathway to adapt to stress in tumor microenvironment, and illustrate the importance of fine-tuning the metabolic pathways for sustaining the proliferation and survival of cancer cells, particularly under stress conditions.


Assuntos
Adaptação Fisiológica/fisiologia , Transformação Celular Viral/fisiologia , Infecções por Herpesviridae/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Modelos Animais de Doenças , Citometria de Fluxo , Imunofluorescência , Técnicas de Silenciamento de Genes , Glicólise/fisiologia , Herpesvirus Humano 8/metabolismo , Humanos , Linfoma de Efusão Primária/metabolismo , Linfoma de Efusão Primária/virologia , Microscopia Confocal , Reação em Cadeia da Polimerase , Ratos
4.
J Pathol ; 242(3): 309-321, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28393364

RESUMO

Primary effusion lymphoma (PEL) is a rare and aggressive B-cell lymphoma with a dismal prognosis caused by infection of Kaposi's sarcoma-associated herpesvirus. Despite the findings that numerous viral genes and cellular pathways are essential for the proliferation and survival of PEL cells, there is currently no effective therapeutic treatment for PEL. Here, we report that the metabolic sensor SIRT1 is functionally required for sustaining the proliferation and survival of PEL cells. Knockdown of SIRT1 with specific shRNAs or inhibition of SIRT1 with an inhibitor (tenovin-6) induced cell cycle arrest and apoptosis in PEL cells. We detected high levels of AMPK activation in PEL cells, reflected in AMPKα1 phosphorylation at T174. Knockdown or inhibition of SIRT1 reduced AMPK activation, indicating that SIRT1 was required for AMPK activation. Interestingly, knockdown of AMPK with specific shRNAs or inhibition of AMPK with the inhibitor compound C recapitulated the phenotype of SIRT1, and induced cell cycle arrest and apoptosis, whereas overexpression of a constitutively active AMPK construct rescued the cytotoxic effect of SIRT1 knockdown. Remarkably, treatment with tenovin-6 effectively inhibited the initiation and progression of PEL, and significantly extended the survival of mice in a murine PEL model. Taken together, these results illustrate that the SIRT1-AMPK axis is essential for maintaining the proliferation and survival of PEL and identify SIRT1 and AMPK as potential therapeutic targets, and tenovin-6 as a candidate therapeutic agent for PEL patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Linfoma de Efusão Primária/fisiopatologia , Sirtuína 1/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/fisiologia , Benzamidas/farmacologia , Pontos de Checagem do Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Técnicas de Silenciamento de Genes , Linfoma de Efusão Primária/enzimologia , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos Endogâmicos NOD , Camundongos SCID , Fosforilação/fisiologia , Sirtuína 1/antagonistas & inibidores
5.
J Virol ; 90(14): 6515-6525, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27147746

RESUMO

UNLABELLED: The host intracellular antiviral restriction factors inhibit viral infection and replication. The 5'-AMP-activated protein kinase (AMPK) is a cellular energy sensor regulating metabolic homeostasis. Activated AMPK inhibits the replication of numerous RNA viruses but enhances the entry of vaccinia virus. However, the role of AMPK in herpesvirus infection is unclear. In this study, we showed that the constitutive AMPK activity restricted Kaposi's sarcoma-associated herpesvirus (KSHV) lytic replication in primary human umbilical vein endothelial cells while KSHV infection did not markedly affect the endogenous AMPK activity. Knockdown of the AMPKα1 considerably enhanced the expression of viral lytic genes and the production of infectious virions, while overexpression of a constitutively active AMPK had the opposite effects. Accordingly, an AMPK inhibitor, compound C, augmented viral lytic gene expressions and virion productions but an AMPK agonist, 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), suppressed both. Furthermore, a common diabetes drug, metformin, which carries an AMPK-agonistic activity, drastically inhibited the expression of viral lytic genes and the production of infectious virions, suggesting the use of metformin as a therapeutic agent for KSHV infection and replication. Together, these results identify the host AMPK as a KSHV restriction factor that can serve as a potential therapeutic target. IMPORTANCE: Host cells encode specific proteins to restrict viral infection and replication. Kaposi's sarcoma-associated herpesvirus (KSHV) is a human tumor virus associated with several cancers. In this study, we have identified 5'-AMP-activated protein kinase (AMPK), a cellular energy sensor, as a restriction factor of KSHV lytic replication during primary infection. Activation of AMPK suppresses, while inhibition of AMPK enhances, KSHV lytic replication by regulating the expression of viral genes. AICAR and metformin, both of which are AMPK agonists currently used in clinics for the treatment of conditions associated with metabolic disorders, inhibit KSHV lytic replication. Thus, our work has identified AMPK as a potential therapeutic target and AICAR and metformin as potential therapeutic agents for KSHV-associated cancers.


Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 8/efeitos dos fármacos , Sarcoma de Kaposi/tratamento farmacológico , Ativação Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Herpesvirus Humano 8/enzimologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Fosforilação/efeitos dos fármacos , Sarcoma de Kaposi/metabolismo , Sarcoma de Kaposi/virologia
6.
J Virol ; 88(11): 6355-67, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24672028

RESUMO

UNLABELLED: Kaposi's sarcoma-associated herpesvirus (KSHV) establishes persistent latent infection in immunocompetent hosts. Disruption of KSHV latency results in viral lytic replication, which promotes the development of KSHV-related malignancies in immunocompromised individuals. While inhibitors of classes I and II histone deacetylases (HDACs) potently reactivate KSHV from latency, the role of class III HDAC sirtuins (SIRTs) in KSHV latency remains unclear. Here, we examined the effects of inhibitors of SIRTs, nicotinamide (NAM) and sirtinol, on KSHV reactivation from latency. Treatment of latently KSHV-infected cells with NAM or sirtinol induced transcripts and proteins of the master lytic transactivator RTA (ORF50), early lytic genes ORF57 and ORF59, and late lytic gene ORF65 and increased the production of infectious virions. NAM increased the acetylation of histones H3 and H4 as well as the level of the active histone H3 trimethyl Lys4 (H3K4me3) mark but decreased the level of the repressive histone H3 trimethyl Lys27 (H3K27me3) mark in the RTA promoter. Consistent with these results, we detected SIRT1 binding to the RTA promoter. Importantly, knockdown of SIRT1 was sufficient to increase the expression of KSHV lytic genes. Accordingly, the level of the H3K4me3 mark in the RTA promoter was increased following SIRT1 knockdown, while that of the H3K27me3 mark was decreased. Furthermore, SIRT1 interacted with RTA and inhibited RTA transactivation of its own promoter and that of its downstream target, the viral interleukin-6 gene. These results indicate that SIRT1 regulates KSHV latency by inhibiting different stages of viral lytic replication and link the cellular metabolic state with the KSHV life cycle. IMPORTANCE: Kaposi's sarcoma-associated herpesvirus (KSHV) is the causal agent of several malignancies, including Kaposi's sarcoma, commonly found in immunocompromised patients. While latent infection is required for the development of KSHV-induced malignancies, viral lytic replication also promotes disease progression. However, the mechanism controlling KSHV latent versus lytic replication remains unclear. In this study, we found that class III histone deacetylases (HDACs), also known as SIRTs, whose activities are linked to the cellular metabolic state, mediate KSHV replication. Inhibitors of SIRTs can reactivate KSHV from latency. SIRTs mediate KSHV latency by epigenetically silencing a key KSHV lytic replication activator, RTA. We found that one of the SIRTs, SIRT1, binds to the RTA promoter to mediate KSHV latency. Knockdown of SIRT1 is sufficient to induce epigenetic remodeling and KSHV lytic replication. SIRT1 also interacts with RTA and inhibits RTA's transactivation function, preventing the expression of its downstream genes. Our results indicate that SIRTs regulate KSHV latency by inhibiting different stages of viral lytic replication and link the cellular metabolic state with the KSHV life cycle.


Assuntos
Regulação Viral da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 8/fisiologia , Sirtuína 1/antagonistas & inibidores , Ativação Viral/efeitos dos fármacos , Benzamidas/farmacologia , Western Blotting , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Primers do DNA/genética , Técnicas de Silenciamento de Genes , Humanos , Proteínas Imediatamente Precoces/metabolismo , Imunoprecipitação , Luciferases , Microscopia Confocal , Naftóis/farmacologia , Niacinamida/farmacologia , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirtuína 1/genética , Transativadores/metabolismo , Ativação Viral/fisiologia , Latência Viral/efeitos dos fármacos
7.
PLoS Pathog ; 8(5): e1002703, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22615563

RESUMO

Ubiquitination, a post-translational modification, mediates diverse cellular functions including endocytic transport of molecules. Kaposi's sarcoma-associated herpesvirus (KSHV), an enveloped herpesvirus, enters endothelial cells primarily through clathrin-mediated endocytosis. Whether ubiquitination and proteasome activity regulates KSHV entry and endocytosis remains unknown. We showed that inhibition of proteasome activity reduced KSHV entry into endothelial cells and intracellular trafficking to nuclei, thus preventing KSHV infection of the cells. Three-dimensional (3-D) analyses revealed accumulation of KSHV particles in a cytoplasmic compartment identified as EEA1+ endosomal vesicles upon proteasome inhibition. KSHV particles are colocalized with ubiquitin-binding proteins epsin and eps15. Furthermore, ubiquitination mediates internalization of both KSHV and one of its receptors integrin ß1. KSHV particles are colocalized with activated forms of the E3 ligase c-Cbl. Knock-down of c-Cbl or inhibition of its phosphorylation reduced viral entry and intracellular trafficking, resulting in decreased KSHV infectivity. These results demonstrate that ubiquitination mediates internalization of both KSHV and one of its cognate receptors integrin ß1, and identify c-Cbl as a potential E3 ligase that facilitates this process.


Assuntos
Endossomos/virologia , Herpesvirus Humano 8/patogenicidade , Células Endoteliais da Veia Umbilical Humana/virologia , Integrina beta1/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Internalização do Vírus , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Linhagem Celular , Endocitose , Endossomos/metabolismo , Regulação Viral da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-cbl/genética , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
8.
Mol Carcinog ; 51(4): 339-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21538577

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma, an angiogenic and inflammatory endothelial cell (EC) tumor that is common in areas of high KSHV prevalence. KSHV encodes a pro-angiogenic viral chemokine receptor (vGPCR) that promotes EC growth in vitro and KS-like tumors in mouse models. vGPCR is therefore considered a viral oncogene that plays a crucial role in the pathobiology of KS. In this study, we show that focal adhesion kinase (FAK) becomes activated upon vGPCR expression in primary ECs and that FAK is required for vGPCR-mediated activation of ERK1/2, NFκB, AP-1, and vGPCR-induced migration and inhibition of anoikis. FAK is crucial to cell motility and tumor invasiveness and is a potential therapeutic target in various malignancies. Our data show that via vGPCR, KSHV has evolved a way to constitutively activate FAK signaling.


Assuntos
Quinase 1 de Adesão Focal/metabolismo , Herpesvirus Humano 8/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Anoikis , Movimento Celular , Meios de Cultivo Condicionados/química , Citoesqueleto/metabolismo , Células Endoteliais/citologia , Fibroblastos/metabolismo , Células HEK293 , Humanos , Integrinas/metabolismo , Camundongos , Neovascularização Patológica , Oncogenes/genética , Transdução de Sinais
9.
Cells ; 11(24)2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36552749

RESUMO

The interaction between the dermal papilla cells (DPCs) and epidermal hair matrix cells (HMCs) of hair follicles (HFs) is crucial for the growth and development of HFs, but the molecular mechanism is complex and remains unclear. MicroRNAs (miRNAs) are the key signaling molecules for cellular communication. In this study, the DPCs and HMCs of yak were isolated and cultured, and the differentially expressed mRNA and miRNA were characterized to analyze the molecular basis of the interaction between DPCs and HMCs during hair follicle (HF) development in yak. The mRNA differential expression and functional enrichment analysis revealed that there were significant differences between DPCs and HMCs, and they showed the molecular functional characteristics of dermal cells and epidermal cells, respectively. Multiple KEGG pathways related to HF development were enriched in the highly expressed genes in DPCs, while the pathways associated with microbiota and immunity were significantly enriched in the highly expressed genes in HMCs. By combining analysis with our previous 10× genomics single-cell transcriptome data, 39 marker genes of DPCs of yak were identified. A total of 123 relatively specifically expressed miRNAs were screened; among these, the miRNAs associated with HF development such as miR-143, miR-214, miR-125b, miR-31, and miR-200 were presented. In conclusion, the large changes in yak DPCs and HMCs for both mRNA and miRNA expression were revealed, and numerous specifically expressed mRNAs and miRNAs in DPCs or HMCs were identified, which may contribute to the interaction and cellular communication between DPCs and HMCs during HF development in yak.


Assuntos
Folículo Piloso , MicroRNAs , Animais , Bovinos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Cultivadas , Transdução de Sinais
10.
Acta Pharmacol Sin ; 31(6): 741-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20523344

RESUMO

AIM: To investigate the antiproliferative and apoptotic effects of gemcitabine combined with gum mastic and the underlying mechanisms in human pancreatic cancer cell lines. METHODS: Cell proliferation and apoptosis were examined using the methyl thiazolyl tetrazolium (MTT) assay and propidium iodine staining, respectively. The expression of Bcl-2, Bax, NF-kappaB p65 subunit, and IkappaBalpha protein was measured using Western blotting. RESULTS: Gemcitabine 0.01-100 microg/mL inhibited cell proliferation and induced apoptosis in both pancreatic cancer BxPC-3 and COLO 357 cells. Gum mastic 40 microg/mL significantly potentiated the antiproliferative and apoptotic effects of gemcitabine 10 microg/mL after 72-h treatment. When cells were treated with gemcitabine in combination with gum mastic, the IkappaBalpha level was increased, whereas NF-kappaB activation was blocked; the expression of Bax protein was substantially increased, but Bcl-2 protein was down-regulated. CONCLUSION: Gemcitabine combined with gum mastic causes potent apoptosis in pancreatic cancer cells. The combination may be an effective therapeutic strategy for pancreatic cancer.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/patologia , Resinas Vegetais/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Citometria de Fluxo , Genes bcl-2 , Inibidores do Crescimento/uso terapêutico , Humanos , Proteínas I-kappa B/metabolismo , Resina Mástique , NF-kappa B/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Resinas Vegetais/uso terapêutico , Proteína X Associada a bcl-2/metabolismo , Gencitabina
11.
Prostate ; 69(15): 1643-50, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19623543

RESUMO

BACKGROUND: Hypermethylation of CpG islands is a common epigenetic alteration associated with cancer. Tumor suppressor genes retinoic acid receptor beta (RARbeta) and PDLIM4 are hypermethylated and silenced in prostate cancer (PCa) tissues and PCa cell lines compared to normal prostate cells. METHODS: In this study, a benign prostate epithelial cell line RWPE1 was used as a model to study the epigenetic regulation of Myc on the RARbeta and PDLIM4 promoters. Forced Myc overexpression inhibited the RARbeta and PDLIM4 expression. RESULTS: Pyrosequencing study showed that Myc overexpression increased methylation in several CpG sites of both promoters. A DNA methylation inhibitor 5-aza-2'-deoxycytidine reversed the epigenetic alteration effect of Myc on both RARbeta and PDLIM4. CONCLUSION: The epigenetic regulation of Myc may be related to its up-regulation of the DNA methyltransferase DNMT3a and DNMT3b.


Assuntos
Proteínas de Ligação a DNA/genética , Genes myc , Próstata/fisiologia , Receptores do Ácido Retinoico/genética , Western Blotting , Processos de Crescimento Celular/genética , Linhagem Celular , DNA/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , DNA Metiltransferase 3A , Epigênese Genética , Perfilação da Expressão Gênica , Humanos , Proteínas com Domínio LIM , Masculino , Reação em Cadeia da Polimerase , Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Análise de Sequência de DNA , Transfecção , DNA Metiltransferase 3B
12.
Mini Rev Med Chem ; 9(3): 395-400, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19275732

RESUMO

Prostate cancer (PCa) is a common cause of death in men and remains incurable in the androgen-refractory phase. Growing evidence has shown that the androgen receptor (AR) and signal transducers and activators of transcription 3 (STAT3) could be effective targets for androgen-refractory PCa therapy. Many strategies have been reported to inhibit the AR or STAT3 activities. In this review, we focus on the AR N-terminal domain and AR chaperones, as well as small molecule inhibitors to STAT3 with which we discuss some new approaches to target the AR and STAT3 as potential treatments for androgen-refractory PCa.


Assuntos
Antagonistas de Receptores de Andrógenos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Ensaios Clínicos como Assunto , Humanos , Masculino , Chaperonas Moleculares/antagonistas & inibidores , Estrutura Molecular , Receptores Androgênicos/metabolismo , Fator de Transcrição STAT3/metabolismo
13.
Cell Biol Int ; 33(1): 57-64, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18957327

RESUMO

This study was to investigate the effect of phenethyl isothiocyanate (PEITC), a constituent of many edible cruciferous vegetables, on the expression of alpha- and beta-tubulins, which are the main components of microtubules in prostate cancer cells. Flow cytometry, light microscopy and western blot were used to study the cell cycle distribution, morphology changes and the expression of alpha- and beta-tubulins in prostate cancer cells treated with PEITC. The results showed that PEITC-induced G2-M cell phase arrest and inhibited the expression of alpha- and beta-tubulin proteins in a number of human prostatic carcinoma cell lines. Further, it is showed that this inhibitory effect could be reversed by antioxidant N-acetyl cysteine and proteasome inhibitor MG132. Finally, it is concluded that PEITC inhibited the expression of alpha- and beta-tubulins in prostate cancer cells, which is at least related to the oxygen reaction species and protein degradation.


Assuntos
Anticarcinógenos/farmacologia , Ciclo Celular/efeitos dos fármacos , Isotiocianatos/farmacologia , Neoplasias da Próstata/metabolismo , Tubulina (Proteína)/metabolismo , Antioxidantes/farmacologia , Western Blotting , Linhagem Celular Tumoral , Cisteína/farmacologia , Citometria de Fluxo , Fase G2/efeitos dos fármacos , Humanos , Leupeptinas/farmacologia , Masculino , Isoformas de Proteínas/metabolismo
14.
Acta Biochim Biophys Sin (Shanghai) ; 40(2): 125-32, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18235974

RESUMO

Paraquat (PQ, 1,1'-dimethyl-4,4'-bipyridinium), a widely-used herbicide, has been suggested as a potential etiologic factor for the development of Parkinson's disease. In recent years, many studies have focused on the mechanism(s) of PQ neurotoxicity. In this study, we examined the neuroprotective effect of manganese (III) meso-tetrakis (N,N'-diethylimidazolium) porphyrin (MnTDM), a superoxide dismutase/catalase mimetic, on PQ-induced oxidative stress and apoptosis in 1RB3AN27 (N27) cells, a dopaminergic neuronal cell line. The results indicated that MnTDM significantly attenuated PQ-induced loss of cell viability, glutathione depletion, and reactive oxygen species production. MnTDM also ameliorated PQ-induced morphological nuclear changes of apoptosis and increased rates of apoptosis. In addition, our data provide direct evidence that MnTDM suppressed PQ-induced caspase-3 cleavage, possibly a key event of PQ neurotoxicity. These observations suggested that oxidative stress and apoptosis are implicated in PQ-induced neurotoxicity and this toxicity could be prevented by MnTDM. These findings also proposed a novel therapeutic approach for Parkinson's disease and other disorders associated with oxidative stress.


Assuntos
Metaloporfirinas/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Paraquat/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Catalase/metabolismo , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Humanos , Modelos Biológicos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Paraquat/antagonistas & inibidores , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
16.
Oncotarget ; 8(9): 14912-14924, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28118604

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is one of the most aggressive non-Hodgkin lymphomas. It is curable but one-third of cases are refractory to therapy or relapse after initial response highlighting the urgent need for developing novel therapeutic approaches. Targeting sirtuins, particularly SIRT1 by genetic approaches or using pharmaceutical inhibitor tenovin-6, has shown promising therapeutic potential in various hematopoietic malignancies. However, it remains unknown whether these approaches are effective for DLBCL. In this study, we have found that tenovin-6 potently inhibits the proliferation and survival of DLBCL cells. Surprisingly, specific knockdown of SIRT1/2/3 has no effect on DLBCL. Mechanistically, tenovin-6 increases the level of microtubule-associated protein 1 light chain 3B (LC3B)-II in a SIRT1/2/3- and p53-independent manner in DLBCL cell lines. Tenovin-6-mediated increase of LC3B-II is through inhibition of classical autophagy pathway. Furthermore, inhibition of the autophagy pathway by using other inhibitors or by knocking down key genes in the pathway impairs cell proliferation and survival of DLBCL cells. These results indicate that targeting the autophagic pathway could be a novel therapeutic strategy for DLBCL and that precaution should be taken to interpret data where tenovin-6 was used as an inhibitor of sirtuins.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Benzamidas/farmacologia , Biomarcadores Tumorais/metabolismo , Proliferação de Células/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Associadas aos Microtúbulos/metabolismo , Antineoplásicos/farmacologia , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Células Tumorais Cultivadas
18.
Yao Xue Xue Bao ; 41(9): 819-24, 2006 Sep.
Artigo em Zh | MEDLINE | ID: mdl-17111826

RESUMO

AIM: To further uncover the possible mechanism of quercetin-mediated inhibitory effect on prostate cancer cells. METHODS: The cell extracts treated with quercetin or without treatment were used for checking protein expression levels of c-Jun and cAMP response element binding protein (CREB)-binding protein (CBP) by Western blotting assay. Regulatory effects of c-Jun and CBP on the function of androgen receptor (AR) were examined by cotransfection experiment. Finally, a physical interaction of c-Jun and the AR was investigated by coimmunoprecipitation. RESULTS: Quercetin dramatically induced the protein expression of c-Jun which in turn inhibited the AR function. Meanwhile, quercetin had no detectable effect on CBP expression, and the results of transient transfection demonstrated that the ectopic CBP stimulated the transcriptional activity of AR, whereas CBP-mediated stimulation could be attenuated by quercetin. Furthermore, physical interaction of c-Jun and the AR was confirmed by coimmunoprecipitation result. CONCLUSION: Overexpression of c-Jun induced by quercetin had inhibitory effect on the function of AR protein, and increased CBP expression did not reverse the inhibition by quercetin. Together, quercetin-mediated inhibition on the AR function might be not by competition with limited amount of CBP in the cell, but through a direct association of c-Jun and the AR.


Assuntos
Proteína de Ligação a CREB/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Quercetina/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/fisiologia , Linhagem Celular Tumoral , Humanos , Imunoprecipitação , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/fisiologia , Receptores Androgênicos/genética , Receptores Androgênicos/fisiologia , Transfecção
19.
Oncotarget ; 7(46): 75698-75711, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27708228

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic virus associated with Kaposi's sarcoma (KS), a malignancy commonly found in AIDS patients. Despite intensive studies in the last two decades, the mechanism of KSHV-induced cellular transformation and tumorigenesis remains unclear. In this study, we found that the expression of SIRT1, a metabolic sensor, was upregulated in a variety of KSHV-infected cells. In a model of KSHV-induced cellular transformation, SIRT1 knockdown with shRNAs or knockout by CRISPR/Cas9 gene editing dramatically suppressed cell proliferation and colony formation in soft agar of KSHV-transformed cells by inducing cell cycle arrest and contact inhibition. SIRT1 knockdown or knockout induced the expression of cyclin-dependent kinase inhibitor 1B (p27Kip1). Consequently, p27 knockdown rescued the inhibitory effect of SIRT1 knockdown or knockout on cell proliferation and colony formation. Furthermore, treatment of KSHV-transformed cells with a SIRT1 inhibitor, nicotinamide (NAM), had the same effect as SIRT1 knockdown and knockout. NAM significantly inhibited cell proliferation in culture and colony formation in soft agar, and induced cell cycle arrest. Significantly, NAM inhibited the progression of tumors and extended the survival of mice in a KSHV-induced tumor model. Collectively, these results demonstrate that SIRT1 suppression of p27 is required for KSHV-induced tumorigenesis and identify a potential therapeutic target for KS.


Assuntos
Inibição de Contato/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Herpesvirus Humano 8/fisiologia , Sarcoma de Kaposi/etiologia , Sarcoma de Kaposi/metabolismo , Sirtuína 1/metabolismo , Linhagem Celular Transformada , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Humanos , Modelos Biológicos , Sarcoma de Kaposi/patologia , Sirtuína 1/genética
20.
Chin J Physiol ; 48(3): 160-6, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16304843

RESUMO

Maspin is a serine protease inhibitor (serpin) with tumor-suppressing function in mammary gland. It is down-regulated in primary prostate cancer cells and lost in metastatic cells. To better understand the transcriptional regulation of maspin gene, the 860bp (-765 approximately +95) of its promoter sequence was amplified by PCR from the human genomic DNA. Then this 860bp sequence and a series of deletions from 5' and 3' ends were inserted into the upstream of luciferase reporter gene respectively. Results from dual luciferase reporter assay and electrophoretic mobility shift assay indicated that there were a negative androgen-responsive element (ARE) in the region of -277 to -262 and a positive Sp1 element in the region of +14 to +35, respectively. In addition, androgen receptor (AR) can recognize and bind to the ARE element, and then inhibit the activity of maspin promoter.


Assuntos
Androgênios/fisiologia , Regiões Promotoras Genéticas/genética , Neoplasias da Próstata/genética , Elementos de Resposta , Serpinas/genética , Fator de Transcrição Sp1/genética , Sequência de Bases , Linhagem Celular Tumoral , Clonagem Molecular , Deleção de Genes , Genes Supressores de Tumor , Humanos , Masculino , Dados de Sequência Molecular , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Serpinas/metabolismo
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