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1.
Nat Cell Biol ; 21(4): 533, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833696

RESUMO

In the version of Supplementary Fig. 3c originally published with this Article, the authors mistakenly duplicated a blot from Supplementary Fig. 3b. The correct versions of these figures are shown below. In addition, two independent repeats of the experiments presented in Supplementary Figs. 3b and 3c, showing results consistent with those originally reported, have been deposited in Figshare ( 10.6084/m9.figshare.7545263 ).

2.
Nat Cell Biol ; 21(5): 664, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30820041

RESUMO

In the version of Supplementary Fig. 6c originally published with this Article, the immunoprecipitation (IP) and immunoblotting (IB) tags in the top panel were mislabelled. In addition, in Supplementary Fig. 6e, the blot of the IP: Numb; IB: ß-Trcp panel for HCT15 was mistakenly duplicated for HCT116. The correct versions of these figures are shown below. An independent repeat of the experiments presented in Supplementary Fig. 6c and e, showing results that are consistent with those reported in the unprocessed blots, have been deposited in figshare ( 10.6084/m9.figshare.7570685 ).

3.
EMBO Mol Med ; 10(8)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29930174

RESUMO

The adaptive cellular response to low oxygen tensions is mediated by the hypoxia-inducible factors (HIFs), a family of heterodimeric transcription factors composed of HIF-α and HIF-ß subunits. Prolonged HIF expression is a key contributor to cellular transformation, tumorigenesis and metastasis. As such, HIF degradation under hypoxic conditions is an essential homeostatic and tumour-suppressive mechanism. LIMD1 complexes with PHD2 and VHL in physiological oxygen levels (normoxia) to facilitate proteasomal degradation of the HIF-α subunit. Here, we identify LIMD1 as a HIF-1 target gene, which mediates a previously uncharacterised, negative regulatory feedback mechanism for hypoxic HIF-α degradation by modulating PHD2-LIMD1-VHL complex formation. Hypoxic induction of LIMD1 expression results in increased HIF-α protein degradation, inhibiting HIF-1 target gene expression, tumour growth and vascularisation. Furthermore, we report that copy number variation at the LIMD1 locus occurs in 47.1% of lung adenocarcinoma patients, correlates with enhanced expression of a HIF target gene signature and is a negative prognostic indicator. Taken together, our data open a new field of research into the aetiology, diagnosis and prognosis of LIMD1-negative lung cancers.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Neoplasias Pulmonares/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Hipóxia Celular/genética , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Retroalimentação Fisiológica , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular/genética
4.
Biomed Res Int ; 2018: 4037865, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30643803

RESUMO

Using our novel surgical model of simultaneous intestinal adaptation "A" and neointestinal regeneration "N" conditions in individual rats to determine feasibility for research and clinical application, we further utilized next generation RNA sequencing (RNA-Seq) here in normal control tissue and both conditions ("A" and "N") across time to decipher transcriptome changes in neoregeneration and adaptation of intestinal tissue at weeks 1, 4, and 12. We also performed bioinformatics analyses to identify key growth factors for improving intestinal adaptation and neointestinal regeneration. Our analyses indicate several interesting phenomena. First, Gene Ontology and pathway analyses indicate that cell cycle and DNA replication processes are enhanced in week 1 "A"; however, in week 1 "N", many immune-related processes are involved. Second, we found some growth factors upregulated or downregulated especially in week 1 "N" versus "A". Third, based on each condition and time point versus normal control tissue, we found in week 1 "N" BMP2, BMP3, and NTF3 are significantly and specifically downregulated, indicating that the regenerative process may be inhibited in the absence of these growth factors. This study reveals complex growth factor regulation in small neointestinal regeneration and intestinal adaptation and provides potential applications in tissue engineering by introducing key growth factors identified here into the injury site.


Assuntos
Ciclo Celular/fisiologia , Perfilação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular , Intestinos/fisiologia , Regeneração/fisiologia , Animais , Proteína Morfogenética Óssea 2/biossíntese , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 3/biossíntese , Proteína Morfogenética Óssea 3/genética , Ontologia Genética , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Ratos , Ratos Sprague-Dawley
5.
Neuro Oncol ; 20(4): 519-530, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29036598

RESUMO

Background: Pediatric central nervous system germ cell tumors (CNSGCTs) are rare and heterogeneous neoplasms, which can be divided into germinomas and nongerminomatous germ cell tumors (NGGCTs). NGGCTs are further subdivided into mature teratomas and nongerminomatous malignant GCTs (NGMGCTs). Clinical outcomes suggest that NGMGCTs have poor prognosis and survival and that they require more extensive radiotherapy and adjuvant chemotherapy. However, the mechanisms underlying this difference are still unclear. DNA methylation alteration is generally acknowledged to cause therapeutic resistance in cancers. We hypothesized that the pediatric NGMGCTs exhibit a different genome-wide DNA methylation pattern, which is involved in the mechanism of its therapeutic resistance. Methods: We performed methylation and hydroxymethylation DNA immunoprecipitation sequencing, mRNA expression microarray, and small RNA sequencing (smRNA-seq) to determine methylation-regulated genes, including microRNAs (miRNAs). Results: The expression levels of 97 genes and 8 miRNAs were correlated with promoter DNA methylation and hydroxymethylation status, such as the miR-199/-214 cluster, and treatment with DNA demethylating agent 5-aza-2'-deoxycytidine elevated its expression level. Furthermore, smRNA-seq analysis showed 27 novel miRNA candidates with differential expression between germinomas and NGMGCTs. Overexpresssion of miR-214-3p in NCCIT cells leads to reduced expression of the pro-apoptotic protein BCL2-like 11 and induces cisplatin resistance. Conclusions: We interrogated the differential DNA methylation patterns between germinomas and NGMGCTs and proposed a mechanism for chemoresistance in NGMGCTs. In addition, our sequencing data provide a roadmap for further pediatric CNSGCT research and potential targets for the development of new therapeutic strategies.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Cisplatino/farmacologia , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Testiculares/genética , Adolescente , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genoma Humano , Humanos , Lactente , Recém-Nascido , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/patologia , Regiões Promotoras Genéticas , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia , Células Tumorais Cultivadas
6.
PLoS One ; 12(7): e0181562, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28727754

RESUMO

Functional impairment of endothelial colony-forming cells (ECFCs), a specific cell lineage of endothelial progenitor cells (EPCs) is highly associated with the severity of coronary artery disease (CAD), the most common type of cardiovascular disease (CVD). Emerging evidence show that circulating microRNAs (miRNAs) in CAD patients' body fluid hold a great potential as biomarkers. However, our knowledge of the role of circulating miRNA in regulating the function of ECFCs and the progression of CAD is still in its infancy. We showed that when ECFCs from healthy volunteers were incubated with conditioned medium or purified exosomes of cultured CAD ECFCs, the secretory factors from CAD ECFCs dysregulated migration and tube formation ability of healthy ECFCs. It is known that exosomes influence the physiology of recipient cells by introducing RNAs including miRNAs. By using small RNA sequencing (smRNA-seq), we deciphered the circulating miRNome in the plasma of healthy individual and CAD patients, and found that the plasma miRNA spectrum from CAD patients was significantly different from that of healthy control. Interestingly, smRNA-seq of both healthy and CAD ECFCs showed that twelve miRNAs that had a higher expression in the plasma of CAD patients also showed higher expression in CAD ECFCs when compared with healthy control. This result suggests that these miRNAs may be involved in the regulation of ECFC functions. For identification of potential mRNA targets of the differentially expressed miRNA in CAD patients, cDNA microarray analysis was performed to identify the angiogenesis-related genes that were down-regulated in CAD ECFCs and Pearson's correlation were used to identify miRNAs that were negatively correlated with the identified angiogenesis-related genes. RT-qPCR analysis of the five miRNAs that negatively correlated with the down-regulated angiogenesis-related genes in plasma and ECFC of CAD patients showed miR-146a-5p and miR-146b-5p up-regulation compared to healthy control. Knockdown of miR-146a-5p or miR-146b-5p in CAD ECFCs enhanced migration and tube formation activity in diseased ECFCs. Contrarily, overexpression of miR-146a-5p or miR-146b-5p in healthy ECFC repressed migration and tube formation in ECFCs. TargetScan analysis showed that miR-146a-5p and miR-146b-5p target many of the angiogenesis-related genes that were down-regulated in CAD ECFCs. Knockdown of miR-146a-5p or miR-146b-5p restores CAV1 and RHOJ levels in CAD ECFCs. Reporter assays confirmed the direct binding and repression of miR-146a-5p and miR-146b-5p to the 3'-UTR of mRNA of RHOJ, a positive regulator of angiogenic potential in endothelial cells. Consistently, RHOJ knockdown inhibited the migration and tube formation ability in ECFCs. Collectively, we discovered the dysregulation of miR-146a-5p/RHOJ and miR-146b-5p/RHOJ axis in the plasma and ECFCs of CAD patients that could be used as biomarkers or therapeutic targets for CAD and other angiogenesis-related diseases.


Assuntos
Doença da Artéria Coronariana/metabolismo , Células Endoteliais/metabolismo , Retroalimentação Fisiológica/fisiologia , MicroRNAs/metabolismo , Biomarcadores/sangue , Caveolina 1/metabolismo , Linhagem da Célula , Movimento Celular/fisiologia , Células Cultivadas , Meios de Cultivo Condicionados/metabolismo , Células Progenitoras Endoteliais/metabolismo , Exossomos/metabolismo , Técnicas de Silenciamento de Genes , Humanos , MicroRNAs/genética , RNA Mensageiro/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo
7.
Oncotarget ; 8(13): 21266-21280, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28177885

RESUMO

Metastasis accounts for the high mortality rate associated with colorectal cancer (CRC), but metastasis regulators are not fully understood. To identify a novel gene involved in tumor metastasis, we used oligonucleotide microarrays, transcriptome distance analyses, and machine learning algorithms to determine links between primary and metastatic colorectal cancers. Aminopeptidase A (APA; also known as ENPEP) was selected as our focus because its relationship with colorectal cancer requires clarification. Higher APA mRNA levels were observed in patients in advanced stages of cancer, suggesting a correlation between ENPEP and degree of malignancy. Our data also indicate that APA overexpression in CRC cells induced cell migration, invasion, anchorage-independent capability, and mesenchyme-like characteristics (e.g., EMT markers). We also observed TWIST induction in APA-overexpressing SW480 cells and TWIST down-regulation in HT29 cells knocked down with APA. Both APA silencing and impaired APA activity were found to reduce migratory capacity, cancer anchorage, stemness properties, and drug resistance in vitro and in vivo. We therefore suggest that APA enzymatic activity affects tumor initiation and cancer malignancy in a TWIST-dependent manner. Results from RT-qPCR and the immunohistochemical staining of specimens taken from CRC patients indicate a significant correlation between APA and TWIST. According to data from SurvExpress analyses of TWIST1 and APA mRNA expression profiles, high APA and TWIST expression are positively correlated with poor CRC prognosis. APA may act as a prognostic factor and/or therapeutic target for CRC metastasis and recurrence.


Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias Colorretais/metabolismo , Glutamil Aminopeptidase/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/biossíntese , Proteína 1 Relacionada a Twist/biossíntese , Animais , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Sítio-Dirigida , Células-Tronco Neoplásicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Regulação para Cima
8.
J Vasc Res ; 54(1): 22-32, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28122380

RESUMO

BACKGROUND/AIMS: Endothelial colony-forming cells (ECFCs) have the potential to be used in regenerative medicine. Dysfunction of ECFCs is correlated with the onset of cardiovascular disorders, especially coronary artery disease (CAD). Binding of vascular endothelial growth factor A (VEGFA) to vascular endothelial growth factor receptor-2 (VEGFR2) triggers cell motility and angiogenesis of ECFCs, which are crucial to vascular repair. METHODS: To identify the miRNA-VEGFR2-dependent regulation of ECFC functions, ECFCs isolated from peripheral blood of disease-free and CAD individuals were subjected to small RNA sequencing for identification of anti-VEGFR2 miRNAs. The angiogenic activities of the miRNAs were determined in both in vitro and in vivo mice models. RESULTS: Three miRNAs, namely miR-410-3p, miR-497-5p, and miR-2355-5p, were identified to be upregulated in CAD-ECFCs, and VEGFR2 was their common target gene. Knockdown of these miRNAs not only restored the expression of VEGFR2 and increased angiogenic activities of CAD-ECFCs in vitro, but also promoted blood flow recovery in ischemic limbs in vivo. miR-410-3p, miR-497-5p, and miR-2355-5p could serve as potential biomarkers for CAD detection as they are highly expressed in the plasma of CAD patients. CONCLUSIONS: This modulation could help develop new therapeutic modalities for cardiovascular diseases and other vascular dysregulated diseases, especially tumor angiogenesis.


Assuntos
Doença da Artéria Coronariana/metabolismo , Células Progenitoras Endoteliais/metabolismo , MicroRNAs/metabolismo , Neovascularização Fisiológica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Antagomirs/genética , Antagomirs/metabolismo , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Células Cultivadas , Biologia Computacional , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Modelos Animais de Doenças , Células Progenitoras Endoteliais/patologia , Células Progenitoras Endoteliais/transplante , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Membro Posterior , Humanos , Isquemia/genética , Isquemia/metabolismo , Isquemia/fisiopatologia , Isquemia/cirurgia , Camundongos Nus , MicroRNAs/genética , Músculo Esquelético/irrigação sanguínea , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Fatores de Tempo , Transfecção , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
9.
Histopathology ; 70(3): 442-455, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27632954

RESUMO

AIMS: Previously, we reported an association between Epstein-Barr virus (EBV)-positive Hodgkin lymphoma (HL), older age, and poorer prognosis. The aim of this study was to investigate the mechanisms underlying this association. METHODS AND RESULTS: Transfection of HL cell lines with EBV latent membrane protein-1 (LMP1) resulted in up-regulation of many cytokine genes as assessed by the use of oligonucleotide microarrays. The up-regulation of cytokines was validated by using an inflammatory cytokine protein array: macrophage inflammatory protein (MIP)-1α, MIP-1ß, and interleukin (IL)-13. Immunostaining of HL samples (n = 104) showed that expression of MIP-1α, MIP-1ß and IL-13 correlated with EBV infection and LMP1 expression. Combined expression of these cytokines was more common in patients aged >60 years (P < 0.001), and was associated with a poorer prognosis (P = 0.042). In another cohort, serum levels of MIP-1α, MIP-1ß and IL-13 were increased in HL patients (n = 53) and highest in EBV-positive HL patients as compared with healthy controls (n = 40). Xenograft mice injected with EBV-positive HL cells had higher serum levels of MIP-1α, MIP-1ß and IL-13 than mice injected with EBV-negative HL cells, although there was no difference in growth. CONCLUSIONS: EBV infection appears to promote the release of cytokines in HL patients, and negatively impacts on patient survival. Physiological immunosenescence probably explains the association between EBV infection and older age. Cytokine modulation is a potential therapeutic target for EBV-positive HL patients.


Assuntos
Citocinas/biossíntese , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Doença de Hodgkin/virologia , Proteínas da Matriz Viral/metabolismo , Adulto , Envelhecimento , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Xenoenxertos , Doença de Hodgkin/imunologia , Doença de Hodgkin/mortalidade , Humanos , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Análise Serial de Tecidos , Regulação para Cima
10.
Oncotarget ; 7(15): 19723-37, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-26933822

RESUMO

Pediatric high-grade gliomas (pHGGs) are aggressive brain tumors affecting children, and outcomes have remained dismal, even with access to new multimodal therapies. In this study, we compared the miRNomes and transcriptomes of pediatric low- (pLGGs) and high-grade gliomas (pHGGs) using small RNA sequencing (smRNA-Seq) and gene expression microarray, respectively. Through integrated bioinformatics analyses and experimental validation, we identified miR-137 and miR-6500-3p as significantly downregulated in pHGGs. miR-137 or miR-6500-3p overexpression reduced cell proliferation in two pHGG cell lines, SF188 and UW479. CENPE, KIF14 and NCAPG levels were significantly higher in pHGGs than pLGGs, and were direct targets of miR-137 or miR-6500-3p. Furthermore, knockdown of CENPE, KIF14 or NCAPG combined with temozolomide treatment resulted in a combined suppressive effect on pHGG cell proliferation. In summary, our results identify novel mRNA/miRNA interactions that contribute to pediatric glioma malignancy and represent potential targets for the development of new therapeutic strategies.


Assuntos
Neoplasias Encefálicas/genética , Proliferação de Células/genética , Regulação para Baixo , Glioma/genética , MicroRNAs/genética , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/patologia , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Criança , Pré-Escolar , Proteínas Cromossômicas não Histona/genética , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , Cinesinas/genética , Masculino , Gradação de Tumores , Proteínas Oncogênicas/genética , Temozolomida
11.
OMICS ; 20(3): 191-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26910904

RESUMO

Organ regeneration therapies using multipotent mesenchymal stem cells (MSCs) are currently being investigated for a variety of common complex diseases. Understanding the molecular regulation of MSC biology will benefit regenerative medicine. MicroRNAs (miRNAs) act as regulators in MSC stemness. There are approximately 2500 currently known human miRNAs that have been recorded in the miRBase v21 database. In the present study, we identified novel microRNAs involved in MSC stemness and differentiation by obtaining the global microRNA expression profiles (miRNomes) of MSCs from two anatomical locations bone marrow (BM-MSCs) and umbilical cord Wharton's jelly (WJ-MSCs) and from osteogenically and adipogenically differentiated progenies of BM-MSCs. Small RNA sequencing (smRNA-seq) and bioinformatics analyses predicted that 49 uncharacterized miRNA candidates had high cellular expression values in MSCs. Another independent batch of Ago1/2-based RNA immunoprecipitation (RNA-IP) sequencing datasets validated the existence of 40 unreported miRNAs in cells and their associations with the RNA-induced silencing complex (RISC). Nine of these 40 new miRNAs were universally overexpressed in both MSC types; nine others were overexpressed in differentiated cells. A novel miRNA (UNI-118-3p) was specifically expressed in BM-MSCs, as verified using RT-qPCR. Taken together, this report offers comprehensive miRNome profiles for two MSC types, as well as cells differentiated from BM-MSCs. MSC transplantation has the potential to ameliorate degenerative disorders and repair damaged tissues. Interventions involving the above 40 new microRNA members in transplanted MSCs may potentially guide future clinical applications.


Assuntos
Células da Medula Óssea/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Complexo de Inativação Induzido por RNA/genética , Adipócitos/citologia , Adipócitos/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Proliferação de Células , Regulação da Expressão Gênica , Humanos , Imunoprecipitação , Células-Tronco Mesenquimais/citologia , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Complexo de Inativação Induzido por RNA/metabolismo , Análise de Sequência de RNA , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo
12.
BMC Syst Biol ; 10 Suppl 1: 1, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26817819

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have emerged as master regulators of angiogenesis and other cancer-related events. Discovering new angiogenesis-regulating microRNAs (angiomiRs) will eventually help in developing new therapeutic strategies for tumor angiogenesis and cardiovascular diseases. Kaposi's sarcoma (KS), which is induced by the etiological infectious agent KS-associated herpesvirus (KSHV), is a peculiar neoplasm that expresses both blood and lymphatic endothelial markers and possesses extensive neovasculature. Using KSHV and its proteins as baits will be an efficient way to discover new angiomiRs in endothelial cells. Kaposin B is one of the latent viral genes and is expressed in all KSHV tumor cells. Since Kaposin B is a nuclear protein with no DNA-binding domain, it may regulate gene expression by incorporating itself into a transcription complex. RESULTS: We demonstrated that c-Myc and Kaposin B form a transcription complex and bind to the miR-221/-222 promoter, thereby affecting their expression and anti-angiogenic ability. By small RNA sequencing (smRNA-Seq), we revealed that 72.1% (173/240) of Kaposin B up-regulated and 46.5% (113/243) of Kaposin B down-regulated known miRNAs were regulated by c-Myc. We also found that 77 novel miRNA were up-regulated and 28 novel miRNAs were down-regulated in cells expressing both c-Myc and Kaposin B compared with cells expressing Kaposin B only. The result was confirmed by RNA-IP-seq data. CONCLUSIONS: Our study identifies known and novel c-Myc-regulated microRNAs and reveals that a c-Myc-oriented program is coordinated by Kaposin B in KSHV-infected cells.


Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Neovascularização Patológica/genética , Proteínas Proto-Oncogênicas c-myc/fisiologia , Proteínas Virais/fisiologia , Células Endoteliais/metabolismo , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
13.
PLoS One ; 11(1): e0147067, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26799933

RESUMO

Diabetes mellitus (DM) is a metabolic disease that is increasing worldwide. Furthermore, it is associated with the deregulation of vascular-related functions, which can develop into major complications among DM patients. Endothelial colony forming cells (ECFCs) have the potential to bring about medical repairs because of their post-natal angiogenic activities; however, such activities are impaired by high glucose- (HG) and the DM-associated conditions. Far-infrared radiation (FIR) transfers energy as heat that is perceived by the thermoreceptors in human skin. Several studies have revealed that FIR improves vascular endothelial functioning and boost angiogenesis. FIR has been used as anti-inflammatory therapy and as a clinical treatment for peripheral circulation improvement. In addition to vascular repair, there is increasing evidence to show that FIR can be applied to a variety of diseases, including cardiovascular disorders, hypertension and arthritis. Yet mechanism of action of FIR and the biomarkers that indicate FIR effects remain unclear. MicroRNA-134 (miR-134-5p) was identified by small RNA sequencing as being increased in high glucose (HG) treated dfECFCs (HG-dfECFCs). Highly expressed miR-134 was also validated in dmECFCs by RT-qPCR and it is associated with impaired angiogenic activities of ECFCs. The functioning of ECFCs is improved by FIR treatment and this occurs via a reduction in the level of miR-134 and an increase in the NRIP1 transcript, a direct target of miR-134. Using a mouse ischemic hindlimb model, the recovery of impaired blood flow in the presence of HG-dfECFCs was improved by FIR pretreatment and this enhanced functionality was decreased when there was miR-134 overexpression in the FIR pretreated HG-dfECFCs. In conclusion, our results reveal that the deregulation of miR-134 is involved in angiogenic defects found in DM patients. FIR treatment improves the angiogenic activity of HG-dfECFCs and dmECFCs and FIR has potential as a treatment for DM. Detection of miR-134 expression in FIR-treated ECFCs should help us to explore further the effectiveness of FIR therapy.


Assuntos
Endotélio Vascular/fisiopatologia , Glucose/metabolismo , Raios Infravermelhos , MicroRNAs/fisiologia , Animais , Endotélio Vascular/patologia , Extremidades/irrigação sanguínea , Humanos , Isquemia/patologia , Camundongos , MicroRNAs/genética
14.
Nucleic Acids Res ; 44(5): e47, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26582927

RESUMO

BACKGROUND: Fusion transcripts are formed by either fusion genes (DNA level) or trans-splicing events (RNA level). They have been recognized as a promising tool for diagnosing, subtyping and treating cancers. RNA-seq has become a precise and efficient standard for genome-wide screening of such aberration events. Many fusion transcript detection algorithms have been developed for paired-end RNA-seq data but their performance has not been comprehensively evaluated to guide practitioners. In this paper, we evaluated 15 popular algorithms by their precision and recall trade-off, accuracy of supporting reads and computational cost. We further combine top-performing methods for improved ensemble detection. RESULTS: Fifteen fusion transcript detection tools were compared using three synthetic data sets under different coverage, read length, insert size and background noise, and three real data sets with selected experimental validations. No single method dominantly performed the best but SOAPfuse generally performed well, followed by FusionCatcher and JAFFA. We further demonstrated the potential of a meta-caller algorithm by combining top performing methods to re-prioritize candidate fusion transcripts with high confidence that can be followed by experimental validation. CONCLUSION: Our result provides insightful recommendations when applying individual tool or combining top performers to identify fusion transcript candidates.


Assuntos
Algoritmos , Fusão Gênica , Proteínas Mutantes Quiméricas/genética , Proteínas de Fusão Oncogênica/genética , RNA Mensageiro/genética , Software , Processamento Alternativo , Perfilação da Expressão Gênica , Humanos , Neoplasias/genética , Análise de Sequência de RNA
15.
Nucleic Acids Res ; 44(D1): D975-9, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26635391

RESUMO

We previously presented DriverDB, a database that incorporates ∼ 6000 cases of exome-seq data, in addition to annotation databases and published bioinformatics algorithms dedicated to driver gene/mutation identification. The database provides two points of view, 'Cancer' and 'Gene', to help researchers visualize the relationships between cancers and driver genes/mutations. In the updated DriverDBv2 database (http://ngs.ym.edu.tw/driverdb) presented herein, we incorporated >9500 cancer-related RNA-seq datasets and >7000 more exome-seq datasets from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and published papers. Seven additional computational algorithms (meaning that the updated database contains 15 in total), which were developed for driver gene identification, are incorporated into our analysis pipeline, and the results are provided in the 'Cancer' section. Furthermore, there are two main new features, 'Expression' and 'Hotspot', in the 'Gene' section. 'Expression' displays two expression profiles of a gene in terms of sample types and mutation types, respectively. 'Hotspot' indicates the hotspot mutation regions of a gene according to the results provided by four bioinformatics tools. A new function, 'Gene Set', allows users to investigate the relationships among mutations, expression levels and clinical data for a set of genes, a specific dataset and clinical features.


Assuntos
Bases de Dados Genéticas , Genes Neoplásicos , Mutação , Perfilação da Expressão Gênica , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Análise de Sequência
16.
J Ethnopharmacol ; 173: 370-82, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26239152

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Four traditional Chinese herbal remedies (CHR) including Buyang Huanwu decoction (BHD), Xuefu Zhuyu decoction (XZD), Tianma Gouteng decoction (TGD) and Shengyu decoction (SYD) are popular used in treating brain-related dysfunction clinically with different syndrome/pattern based on traditional Chinese medicine (TCM) principles, yet their neuroprotective mechanisms are still unclear. MATERIALS AND METHODS: Mice were subjected to an acute ischemic stroke to examine the efficacy and molecular mechanisms of action underlying these CHR. RESULTS: CHR treatment significantly enhanced the survival rate of stroke mice, with BHD being the most effective CHR. All CHR were superior to recombinant tissue-type plasminogen activator (rt-PA) treatment in successfully ameliorating brain function, infarction, and neurological deficits in stroke mice that also paralleled to improvements in blood-brain barrier damage, inflammation, apoptosis, and neurogenesis. Transcriptome analyses reveals that a total of 774 ischemia-induced probe sets were significantly modulated by four CHR, including 52 commonly upregulated genes and 54 commonly downregulated ones. Among them, activation of neurogenesis-associated signaling pathways and down-regulating inflammation and apoptosis pathways are key common mechanisms in ischemic stroke protection by all CHR. Besides, levels of plasma CX3CL1 and S100a9 in patients could be used as biomarkers for therapeutic evaluation before functional recovery could be observed. CONCLUSION: Our results suggest that using CHR, a combinatory cocktail therapy, is a better way than rt-PA for treating cerebral ischemic-associated diseases through modulating a common as well as a specific group of genes/pathways that may partially explain the syndrome differentiation and treatment principle in TCM.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Calgranulina B/genética , Quimiocina CXCL1/genética , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica , Infarto da Artéria Cerebral Média/genética , Masculino , Medicina Tradicional Chinesa , Camundongos Endogâmicos ICR , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fitoterapia
17.
BMC Med Genomics ; 8: 32, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26109171

RESUMO

BACKGROUND: Pediatric embryonal brain tumors (PEBTs), which encompass medulloblastoma (MB), primitive neuroectodermal tumor (PNET) and atypical teratoid/rhabdoid tumor (AT/RT), are the second most prevalent pediatric brain tumor type. AT/RT is highly malignant and is often misdiagnosed as MB or PNET. The distinction of AT/RT from PNET/MB is of clinical significance because the survival rate of patients with AT/RT is substantially lower. The diagnosis of AT/RT relies primarily on morphologic assessment and immunohistochemical (IHC) staining for a few known markers such as the lack of INI1 protein expression. However, in our clinical practice we have observed several AT/RT-like tumors, that fulfilled histopathological and all other biomarker criteria for a diagnosis of AT/RT, yet retained INI1 immunoreactivity. Recent studies have also reported preserved INI1 immunoreactivity among certain diagnosed AT/RTs. It is therefore necessary to re-evaluate INI1(+), AT/RT-like cases. METHOD: Sanger sequencing, array CGH and mRNA microarray analyses were performed on PEBT samples to investigate their genomic landscapes. RESULTS: Patients with AT/RT and those with INI(+) AT/RT-like tumors showed a similar survival rate, and global array CGH analysis and INI1 gene sequencing showed no differential chromosomal aberration markers between INI1(-) AT/RT and INI(+) AT/RT-like cases. We did not misdiagnose MBs or PNETs as AT/RT-like tumors because transcriptome profiling revealed that not only did AT/RT and INI(+) AT/RT-like cases express distinct mRNA and microRNA profiles, their gene expression patterns were different from those of MBs and PNETs. The most similar transcriptome profile to that of AT/RTs was the profile of embryonic stem cells. However; the transcriptome profile of INI1(+) AT/RT-like tumors was more similar to that of somatic neural stem cells, while the profile of MBs was closer to that of fetal brain tissue. Novel biomarkers were identified that can be used to distinguish INI1(-) AT/RTs, INI1(+) AT/RT-like cases and MBs. CONCLUSION: Our studies revealed a novel INI1(+) ATRT-like subtype among Taiwanese pediatric patients. New diagnostic biomarkers, as well as new therapeutic tactics, can be developed according to the transcriptome data that were unveiled in this work.


Assuntos
Neoplasias Encefálicas/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Genômica , Neoplasias Embrionárias de Células Germinativas/genética , Tumor Rabdoide/genética , Teratoma/genética , Fatores de Transcrição/metabolismo , Adolescente , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Masculino , Meduloblastoma/diagnóstico , Meduloblastoma/genética , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Células-Tronco Neoplásicas/patologia , Prognóstico , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/metabolismo , Tumor Rabdoide/patologia , Proteína SMARCB1 , Teratoma/diagnóstico , Teratoma/metabolismo , Teratoma/patologia , Fatores de Transcrição/genética
18.
J Cell Physiol ; 230(9): 2240-51, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25754990

RESUMO

Breast cancer is a common cancer leading to many deaths among females. Cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) are two highly expressed inflammatory mediators to be induced by the protein kinase C (PKC) signaling via various inflammatory stimuli and both contribute significantly to cancer metastasis/progression. Glucosamine has been shown to act as an anti-inflammation molecule. The aim of this study was to clarify the role and acting mechanism of glucosamine during the PKC-regulation of COX-2/IL-8 expression and the associated impact on breast cancer. In MCF-7 breast cancer cells, glucosamine effectively suppresses the PKC induction of COX-2 and IL-8 promoter activity, mRNA and protein levels, as well as the production of prostaglandin E(2) (PGE(2)) and IL-8. Glucosamine is able to promote COX-2 protein degradation in a calpain-dependent manner and IL-8 protein degradation in calpain-dependent and proteasome-dependent manners. The MAPK and NF-κB pathways are involved in PKC-induced COX-2 expression, but only the NF-κB pathway is involved in PKC-induced IL-8 expression. Glucosamine attenuates PKC-mediated IκBα phosphorylation, nuclear NF-κB translocation, and NF-κB reporter activation. Both PGE(2) and IL-8 promote cell proliferation and IL-8 induces cell migration; thus, glucosamine appears to suppress PKC-induced cell proliferation and migration. Furthermore, glucosamine significantly inhibits the growth of breast cancer xenografts and this is accompanied by a reduction in COX-2 and IL-8 expression. In conclusion, glucosamine seems to attenuate the inflammatory response in vitro and in vivo and this occurs, at least in part by targeting to the NF-κB signaling pathway, resulting in an inhibition of breast cancer cell growth.


Assuntos
Neoplasias da Mama/genética , Ciclo-Oxigenase 2/biossíntese , Interleucina-8/biossíntese , Proteína Quinase C/metabolismo , Animais , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Glucosamina/administração & dosagem , Glucosamina/genética , Humanos , Inflamação/genética , Inflamação/patologia , Células MCF-7 , Camundongos , RNA Mensageiro/biossíntese , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
BMC Genomics ; 16 Suppl 2: S2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25708300

RESUMO

BACKGROUND: Identification of genes with ascending or descending monotonic expression patterns over time or stages of stem cells is an important issue in time-series microarray data analysis. We propose a method named Monotonic Feature Selector (MFSelector) based on a concept of total discriminating error (DEtotal) to identify monotonic genes. MFSelector considers various time stages in stage order (i.e., Stage One vs. other stages, Stages One and Two vs. remaining stages and so on) and computes DEtotal of each gene. MFSelector can successfully identify genes with monotonic characteristics. RESULTS: We have demonstrated the effectiveness of MFSelector on two synthetic data sets and two stem cell differentiation data sets: embryonic stem cell neurogenesis (ESCN) and embryonic stem cell vasculogenesis (ESCV) data sets. We have also performed extensive quantitative comparisons of the three monotonic gene selection approaches. Some of the monotonic marker genes such as OCT4, NANOG, BLBP, discovered from the ESCN dataset exhibit consistent behavior with that reported in other studies. The role of monotonic genes found by MFSelector in either stemness or differentiation is validated using information obtained from Gene Ontology analysis and other literature. We justify and demonstrate that descending genes are involved in the proliferation or self-renewal activity of stem cells, while ascending genes are involved in differentiation of stem cells into variant cell lineages. CONCLUSIONS: We have developed a novel system, easy to use even with no pre-existing knowledge, to identify gene sets with monotonic expression patterns in multi-stage as well as in time-series genomics matrices. The case studies on ESCN and ESCV have helped to get a better understanding of stemness and differentiation. The novel monotonic marker genes discovered from a data set are found to exhibit consistent behavior in another independent data set, demonstrating the utility of the proposed method. The MFSelector R function and data sets can be downloaded from: http://microarray.ym.edu.tw/tools/MFSelector/.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Células-Tronco/metabolismo , Algoritmos , Diferenciação Celular/genética , Linhagem da Célula/genética , Análise por Conglomerados , Proteínas de Homeodomínio/genética , Humanos , Internet , Proteína Homeobox Nanog , Neovascularização Fisiológica/genética , Neurogênese/genética , Fator 3 de Transcrição de Octâmero/genética , Células-Tronco/citologia , Fatores de Tempo
20.
Nucleic Acids Res ; 43(Database issue): D862-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25398902

RESUMO

We previously presented YM500, which is an integrated database for miRNA quantification, isomiR identification, arm switching discovery and novel miRNA prediction from 468 human smRNA-seq datasets. Here in this updated YM500v2 database (http://ngs.ym.edu.tw/ym500/), we focus on the cancer miRNome to make the database more disease-orientated. New miRNA-related algorithms developed after YM500 were included in YM500v2, and, more significantly, more than 8000 cancer-related smRNA-seq datasets (including those of primary tumors, paired normal tissues, PBMC, recurrent tumors, and metastatic tumors) were incorporated into YM500v2. Novel miRNAs (miRNAs not included in the miRBase R21) were not only predicted by three independent algorithms but also cleaned by a new in silico filtration strategy and validated by wetlab data such as Cross-Linked ImmunoPrecipitation sequencing (CLIP-seq) to reduce the false-positive rate. A new function 'Meta-analysis' is additionally provided for allowing users to identify real-time differentially expressed miRNAs and arm-switching events according to customer-defined sample groups and dozens of clinical criteria tidying up by proficient clinicians. Cancer miRNAs identified hold the potential for both basic research and biotech applications.


Assuntos
Bases de Dados de Ácidos Nucleicos , MicroRNAs/química , MicroRNAs/metabolismo , Neoplasias/genética , Perfilação da Expressão Gênica , Humanos , Internet , Análise de Sequência de RNA
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