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1.
Anticancer Res ; 39(9): 4947-4955, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519600

RESUMO

BACKGROUND/AIM: Insulin-like growth factor II mRNA-binding protein 3 (IMP3) plays an important role in the adhesion, invasion, and metastasis of tumor cells. Although emerging evidence suggests that IMP3 promotes tumor progression in several malignancies, the expression of IMP3 and its prognostic implication in adenocarcinoma of the ampulla of Vater (AVAC) has not been clarified to date. MATERIALS AND METHODS: The IMP3 expression status in 87 AVAC tissues was examined using immunostaining, and its association with various clinicopathological features and outcome of patients with AVAC was investigated. RESULTS: The vast majority (87.4%) of AVAC cases displayed at least focal cytoplasmic and membranous IMP3 immunoreactivity in tumor cells, whereas IMP3 expression was consistently absent from normal biliary epithelial cells. Tumor-specific IMP3 expression was associated with submucosal and pancreatic invasion, which were not identified in the corresponding hematoxylin and eosin-stained slides. This finding led to up-staging of the pathological tumor stage in two cases of well-differentiated AVAC. In addition, high IMP3 expression was significantly associated with a poorly differentiated histology (p=0.026). Survival analyses revealed that high IMP3 expression independently predicted shorter recurrence-free (p=0.003) and overall (p=0.029) survival. CONCLUSION: Our study demonstrated tumor-specific IMP3 expression in AVAC, which will be helpful in determining invasion depth and tumor extent in patients with well-differentiated tumors, as well as indicating worse survival of patients with AVAC. Our data highlight IMP3 expression status as a potential diagnostic and prognostic marker for AVAC.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Ampola Hepatopancreática/patologia , Neoplasias do Ducto Colédoco/genética , Neoplasias do Ducto Colédoco/mortalidade , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a RNA/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais , Neoplasias do Ducto Colédoco/diagnóstico , Neoplasias do Ducto Colédoco/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Proteínas de Ligação a RNA/genética , Carga Tumoral
3.
Adv Exp Med Biol ; 1157: 29-39, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31342436

RESUMO

Post-transcriptional regulation of gene expression is fundamental for all forms of life, as it critically contributes to the composition and quantity of a cell's proteome. These processes encompass splicing, polyadenylation, mRNA decay, mRNA editing and modification and translation and are modulated by a variety of RNA-binding proteins (RBPs). Alterations affecting RBP expression and activity contribute to the development of different types of cancer. In this chapter, we discuss current research shedding light on the role of different RBPs in gliomas. These studies place RBPs as modulators of critical signaling pathways, establish their relevance as prognostic markers and open doors for new therapeutic strategies.


Assuntos
Glioma , Proteínas de Ligação a RNA , Glioma/fisiopatologia , Humanos , Poliadenilação , Processamento de RNA , Estabilidade de RNA , Proteínas de Ligação a RNA/metabolismo
4.
Medicine (Baltimore) ; 98(27): e16009, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277094

RESUMO

Bladder cancer is one of the most common malignancies of urinary tract. The current study aimed to investigate the role of insulin-like growth factor II messenger RNA binding protein 3 (IMP3) expression in the prognostic evaluation of non-muscle- invasive urothelial carcinoma of the bladder.Immunohistochemistry (IHC) was carried out to examine IMP3 protein expression in specimens from 183 cases of non-muscle-invasive urothelial carcinoma, 20 cases of muscle-invasive urothelial carcinoma and 20 benign tissues adjacent to cancer tissue.The expression of IMP3 was not detected in the adjacent benign tissues. The expression intensity of IMP3 in muscle-invasive samples was significantly higher than that in non-muscle-invasive urothelial carcinoma specimens (P = .008). IMP3 expression was significantly related with advanced tumor stage (P < .001), advanced tumor grade (P = .004), and tumor recurrence (P < .001) in non-muscle-invasive urothelial carcinomas. Kaplan-Meier analysis showed that IMP3-positive patients had much lower disease-free (P < .001), progression-free (P = .002) and metastasis-free (P = .019) survival rates compared with those with IMP3-negative tumors. By multivariable Cox analysis, we also found that IMP3 expression in non-muscle- invasive urothelial carcinomas proved to be an independent unfavorable prognostic factor of disease-free survival (HR: 2.52; 95% CI, 1.39-4.56; P = .002), progression- free survival (HR: 5.19; 95% CI, 1.54-17.46; P = .008) and metastasis-free survival (HR: 4.87; 95% CI, 1.08-22.02; P = .040).Our results demonstrate that the expression of IMP3 in non-muscle- invasive bladder cancer can serve as an independent predictor that will help recognize the subgroup of patients with a high ability to relapse, progress, and metastasize and who might get the maximum benefit from an early and more aggressive treatment strategy.


Assuntos
Carcinoma de Células de Transição/genética , Proteínas de Ligação a RNA/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Modelos de Riscos Proporcionais , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia
5.
Zhongguo Zhong Yao Za Zhi ; 44(12): 2594-2599, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359729

RESUMO

To study the mechanism and action of Cinnamomi Ramulus in ameliorating intrahepatic cholestasis induced by α-isothiocyanate( ANIT) in rats by regulating FXR pathway. Forty SD rats were randomly divided into normal group,model group,positive control( ursodeoxycholic acid) group( 60 mg·kg~(-1)),Cinnamomi Ramulus treatment( 60 mg·kg~(-1)·d~(-1)) group,and Cinnamomi Ramulus treatment( 20 mg·kg~(-1)·d~(-1)) group,with 8 rats in each group. Except for the normal control group,the other groups were intragastrically administered with the corresponding concentrations of continuous aqueous solution( 0. 005 m L·g~(-1)),once a day,for 7 days.Except for the normal group,the other groups were treated with ANIT( 100 mg·kg~(-1)),once a day,for 3 days. Blood was taken from the abdominal aorta 24 hours after the last administration,and serum alanine aminotransferase( ALT),aspartate aminotransferase( AST),total bilirubin( TBi L),and total bile acid( TBA) were measured. 1. 5-2 cm of rat liver tissue was taken. After fixation with10% formaldehyde,paraffin-embedded sections were taken,HE staining was performed,and immunohistochemistry( IHC) was used to analyze the expression of FXR. RNA and protein were extracted from rat liver tissue to detect FXR mRNA expression,as well as bile acid synthesis and detoxification,transport related SHP,UGT2 B4,BSEP protein expressions at downstream of FXR. Compared with the normal group,serum ALT,AST,TBi L,and TBA levels were elevated in the model group( P<0. 01),liver damage was severe,FXR protein's optical density decreased,FXR mRNA expression decreased,and SHP,UGT2 B4,BSEP protein expressions were decreased( P<0. 05,P<0. 01). Compared with the model group,the drug group could reduce serum ALT,AST,TB,TBA levels to different degrees( P<0. 05,P<0. 01),alleviate liver tissue damage,increase the optical density of FXR protein,and promote the expressions of FXR mRNA and FXR,SHP,BSEP and UGT2 B4 proteins( P<0. 05,P<0. 01). Cinnamomi Ramulus can alleviate ANIT-induced intrahepatic cholestasis,and reduce hepatocyte injury and serum ALT,AST,TBi L and TBA levels. The mechanism may be through FXR-SHP,FXR-UGT2 B4,FXR-BSEP signaling pathways. Therefore,in the pathogenesis of intrahepatic cholestasis,we can try to further explore in alleviating intrahepatic cholestasis with Cinnamomi Ramulus,so as to provide effective drugs for clinical treatment of intrahepatic cholestasis.


Assuntos
Colestase Intra-Hepática/tratamento farmacológico , Cinnamomum/química , Extratos Vegetais/farmacologia , Proteínas de Ligação a RNA/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Ácidos e Sais Biliares/sangue , Bilirrubina/sangue , Colestase Intra-Hepática/induzido quimicamente , Isotiocianatos , Fígado , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
6.
BMC Evol Biol ; 19(1): 149, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337330

RESUMO

BACKGROUND: Adenosine deaminase enzymes of the ADAR family are conserved in metazoans. They convert adenine into inosine in dsRNAs and thus alter both structural properties and the coding potential of their substrates. Acting on exogenous dsRNAs, ADAR1 exerts a pro- or anti-viral role in vertebrates and Drosophila. RESULTS: We traced 4 ADAR homologs in 14 lophotrochozoan genomes and we classified them into ADAD, ADAR1 or ADAR2, based on phylogenetic and structural analyses of the enzymatic domain. Using RNA-seq and quantitative real time PCR we demonstrated the upregulation of one ADAR1 homolog in the bivalve Crassostrea gigas and in the gastropod Haliotis diversicolor supertexta during Ostreid herpesvirus-1 or Haliotid herpesvirus-1 infection. Accordingly, we demonstrated an extensive ADAR-mediated editing of viral RNAs. Single nucleotide variation (SNV) profiles obtained by pairing RNA- and DNA-seq data from the viral infected individuals resulted to be mostly compatible with ADAR-mediated A-to-I editing (up to 97%). SNVs occurred at low frequency in genomic hotspots, denoted by the overlapping of viral genes encoded on opposite DNA strands. The SNV sites and their upstream neighbor nucleotide indicated the targeting of selected adenosines. The analysis of viral sequences suggested that, under the pressure of the ADAR editing, the two Malacoherpesviridae genomes have evolved to reduce the number of deamination targets. CONCLUSIONS: We report, for the first time, evidence of an extensive editing of Malacoherpesviridae RNAs attributable to host ADAR1 enzymes. The analysis of base neighbor preferences, structural features and expression profiles of molluscan ADAR1 supports the conservation of the enzyme function among metazoans and further suggested that ADAR1 exerts an antiviral role in mollusks.


Assuntos
Antivirais/metabolismo , Vírus de DNA/genética , Moluscos/virologia , Edição de RNA/genética , RNA Viral/genética , Proteínas de Ligação a RNA/metabolismo , Animais , Teorema de Bayes , Vírus de DNA/fisiologia , Regulação da Expressão Gênica , Genoma Viral , Modelos Moleculares , Moluscos/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Domínios Proteicos , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Transcriptoma/genética
7.
Eur J Med Chem ; 178: 13-29, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31173968

RESUMO

The oncogenic Epstein-Barr virus (EBV) evades the immune system through limiting the expression of its highly antigenic and essential genome maintenance protein, EBNA1, to the minimal level to ensure viral genome replication, thereby also minimizing the production of EBNA1-derived antigenic peptides. This regulation is based on inhibition of translation of the virally-encoded EBNA1 mRNA, and involves the interaction of host protein nucleolin (NCL) with G-quadruplex (G4) structures that form in the glycine-alanine repeat (GAr)-encoding sequence of the EBNA1 mRNA. Ligands that bind to these G4-RNA can prevent their interaction with NCL, leading to disinhibition of EBNA1 expression and antigen presentation, thereby interfering with the immune evasion of EBNA1 and therefore of EBV (M.J. Lista et al., Nature Commun., 2017, 8, 16043). In this work, we synthesized and studied a series of 20 cationic bis(acylhydrazone) derivatives designed as G4 ligands. The in vitro evaluation showed that most derivatives based on central pyridine (Py), naphthyridine (Naph) or phenanthroline (Phen) units were efficient G4 binders, in contrast to their pyrimidine (Pym) counterparts, which were poor G4 binders due to a significantly different molecular geometry. The influence of lateral heterocyclic units (N-substituted pyridinium or quinolinium residues) on G4-binding properties was also investigated. Two novel compounds, namely PyDH2 and PhenDH2, used at a 5 µM concentration, were able to significantly enhance EBNA1 expression in H1299 cells in a GAr-dependent manner, while being significantly less toxic than the prototype drug PhenDC3 (GI50 > 50 µM). Antigen presentation, RNA pull-down and proximity ligation assays confirmed that the effect of both drugs was related to the disruption of NCL-EBNA1 mRNA interaction and the subsequent promotion of GAr-restricted antigen presentation. Our work provides a novel modular scaffold for the development of G-quadruplex-targeting drugs acting through interference with G4-protein interaction.


Assuntos
Hidrazonas/farmacologia , Evasão da Resposta Imune/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Fosfoproteínas/metabolismo , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Linhagem Celular Tumoral , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Quadruplex G , Herpesvirus Humano 4/genética , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Fatores Imunológicos/síntese química , Fatores Imunológicos/química , Ligantes , Camundongos , RNA Mensageiro/genética
8.
Genes Dev ; 33(15-16): 1048-1068, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31221665

RESUMO

Fetal hematopoietic stem and progenitor cells (HSPCs) hold promise to cure a wide array of hematological diseases, and we previously found a role for the RNA-binding protein (RBP) Lin28b in respecifying adult HSPCs to resemble their fetal counterparts. Here we show by single-cell RNA sequencing that Lin28b alone was insufficient for complete reprogramming of gene expression from the adult toward the fetal pattern. Using proteomics and in situ analyses, we found that Lin28b (and its closely related paralog, Lin28a) directly interacted with Igf2bp3, another RBP, and their enforced co-expression in adult HSPCs reactivated fetal-like B-cell development in vivo more efficiently than either factor alone. In B-cell progenitors, Lin28b and Igf2bp3 jointly stabilized thousands of mRNAs by binding at the same sites, including those of the B-cell regulators Pax5 and Arid3a as well as Igf2bp3 mRNA itself, forming an autoregulatory loop. Our results suggest that Lin28b and Igf2bp3 are at the center of a gene regulatory network that mediates the fetal-adult hematopoietic switch. A method to efficiently generate induced fetal-like hematopoietic stem cells (ifHSCs) will facilitate basic studies of their biology and possibly pave a path toward their clinical application.


Assuntos
Reprogramação Celular/genética , Proteínas de Ligação a DNA/metabolismo , Redes Reguladoras de Genes , Células-Tronco Hematopoéticas/fisiologia , Proteínas de Ligação a RNA/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Proteínas de Ligação a DNA/genética , Camundongos , MicroRNAs/metabolismo , Modelos Animais , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-31176867

RESUMO

In rice field eel (Monopterus albus), germ cell development in the developing gonad has been revealed in detail. However, it is unclear how primordial germ cells (PGCs) migrate to the somatic part of the gonad (genital ridge). This study visualized PGC migration by injecting a chimeric mRNA containing a fluorescent protein fused to the 3' untranslated region (3'UTR) of three different genes, nanos3 of zebrafish (Danio rerio) and dead end (dnd) and vasa of rice field eel. The mRNAs were injected either alone or in pairs into embryos at the one-cell stage. The results showed that mRNAs containing nanos3 and dnd 3'UTRs labeled PGCs over a wider time frame than those containing vasa 3'UTR, suggesting that nanos3 and dnd 3'UTRs are suitable for visualizing PGCs in rice field eel. Using this direct visualization method, the normal migration route of PGCs was observed from the 50%-epiboly stage to hatching stage for the first time, and the ectopic PGCs were also visualized during this period in rice field eel. These findings extend our knowledge of germ cell development, and lay a foundation for further research on the relationship between PGCs and sex differentiation, and on incubation conditions for embryos in rice field eel.


Assuntos
Células Germinativas/metabolismo , Smegmamorpha/embriologia , Regiões 3' não Traduzidas , Sequência de Aminoácidos , Animais , Movimento Celular/genética , Movimento Celular/fisiologia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Células Germinativas/citologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , RNA/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Smegmamorpha/genética , Smegmamorpha/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
Neoplasma ; 66(5): 746-755, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31169019

RESUMO

MiR-21-5p has been identified as an oncogene to enhance human tumor progression. Here, we explored the mechanism by which miR-21-5p regulated the progression and paclitaxel (PTX) resistance in drug-resistant breast cancer (BC) cell lines. qRT-PCR assays were used to assess the expression levels of miR-21-5p and PDCD4 mRNA, and western blotting was used to detect PDCD4 protein level in PTX-resistant BC cell lines. Dual-luciferase reporter assay was used to observe the interaction between miR-21-5p and PDCD4 in PTX-resistant BC cell lines. Cell proliferation ability and IC50 values of PTX were measured by CCK-8 assay, cell cycle progression and apoptosis were determined with flow cytometry analysis, and cell migration and invasion capacities were analyzed using Transwell assay. Xenograft mice assay was used to validate the important role of miR-21-5p as a regulator on PTX-resistance BC cells growth in vivo. Then, we found that miR-21-5p was upregulated and PDCD4 was downregulated in BC tissues and PTX-resistant BC cell lines. MiR-21-5p silencing or PDCD4 overexpression ameliorated PTX resistance and inhibited the progression in PTX-resistant BC cell lines. Moreover, PDCD4 was demonstrated to be a direct target of miR-21-5p. MiR-21-5p exerted its regulatory effect by PDCD4 in PTX-resistant BC cell lines. Additionally, miR-21-5p silencing inhibited tumor growth in vivo. Therefore, our study demonstrated that miR-21-5p silencing ameliorated PTX resistance and inhibited the progression in PTX-resistant BC cell lines at least partly by targeting PDCD4, providing miR-21-5p as an effective therapeutic target for PTX-resistant BC treatment.


Assuntos
Proteínas Reguladoras de Apoptose , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , MicroRNAs , Paclitaxel , Proteínas de Ligação a RNA , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , MicroRNAs/metabolismo , Paclitaxel/farmacologia , Proteínas de Ligação a RNA/metabolismo
11.
Nat Commun ; 10(1): 2458, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165730

RESUMO

During stress, prompt export of stress-inducible transcripts is critical for cell survival. Here, we characterize a function of the SAGA (Spt-Ada-Gcn5 acetyltransferase) deubiquitylating module (DUBm) in monitoring messenger ribonucleoprotein (mRNP) biogenesis to regulate non-canonical mRNA export of stress-inducible transcripts. Our genetic and biochemical analyses suggest that there is a functional relationship between Sgf73p of DUBm and the essential mRNA export factor, Yra1p. Under physiological conditions, Sgf73p is critical for the proper chromatin localization and RNA binding of Yra1p, while also quality controlling the biogenesis of mRNPs in conjunction with the nuclear exosome exonuclease, Rrp6p. Under environmental stress, when immediate transport of stress-inducible transcripts is imperative, Sgf73p facilitates the bypass of canonical surveillance and promotes the timely export of necessary transcripts. Overall, our results show that the Sgf73p-mediated plasticity of gene expression is important for the ability of cells to tolerate stress and regulate proteostasis to survive under environmental uncertainty.


Assuntos
Adaptação Fisiológica , Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/metabolismo , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Estresse Fisiológico , Cromatina/metabolismo , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Proteostase , Transporte de RNA , Saccharomyces cerevisiae , Transativadores/metabolismo
12.
Nat Commun ; 10(1): 2593, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197139

RESUMO

Prion-like domains (PLDs), defined by their low sequence complexity and intrinsic disorder, are present in hundreds of human proteins. Although gain-of-function mutations in the PLDs of neuronal RNA-binding proteins have been linked to neurodegenerative disease progression, the physiological role of PLDs and their range of molecular functions are still largely unknown. Here, we show that the PLD of Drosophila Imp, a conserved component of neuronal ribonucleoprotein (RNP) granules, is essential for the developmentally-controlled localization of Imp RNP granules to axons and regulates in vivo axonal remodeling. Furthermore, we demonstrate that Imp PLD restricts, rather than promotes, granule assembly, revealing a novel modulatory function for PLDs in RNP granule homeostasis. Swapping the position of Imp PLD compromises RNP granule dynamic assembly but not transport, suggesting that these two functions are uncoupled. Together, our study uncovers a physiological function for PLDs in the spatio-temporal control of neuronal RNP assemblies.


Assuntos
Transporte Axonal/fisiologia , Grânulos Citoplasmáticos/metabolismo , Proteínas de Drosophila/metabolismo , Domínios Proteicos/fisiologia , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/metabolismo , Animais , Animais Geneticamente Modificados , Axônios/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Linhagem Celular , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster , Feminino , Microscopia de Fluorescência , Modelos Animais , Príons/química , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética
13.
Nat Commun ; 10(1): 2691, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217428

RESUMO

The MUSASHI (MSI) family of RNA binding proteins (MSI1 and MSI2) contribute to a wide spectrum of cancers including acute myeloid leukemia. We find that the small molecule Ro 08-2750 (Ro) binds directly and selectively to MSI2 and competes for its RNA binding in biochemical assays. Ro treatment in mouse and human myeloid leukemia cells results in an increase in differentiation and apoptosis, inhibition of known MSI-targets, and a shared global gene expression signature similar to shRNA depletion of MSI2. Ro demonstrates in vivo inhibition of c-MYC and reduces disease burden in a murine AML leukemia model. Thus, we identify a small molecule that targets MSI's oncogenic activity. Our study provides a framework for targeting RNA binding proteins in cancer.


Assuntos
Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Experimental/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Pteridinas/farmacologia , Proteínas de Ligação a RNA/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Leucemia Experimental/sangue , Leucemia Mieloide Aguda/sangue , Masculino , Camundongos , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pteridinas/uso terapêutico , RNA/metabolismo , Motivo de Reconhecimento de RNA/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transcriptoma/efeitos dos fármacos , Células Tumorais Cultivadas
14.
Life Sci ; 232: 116606, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254586

RESUMO

AIMS: Bupivacaine, a common local anesthetic, can cause neurotoxicity and abnormal neuro-disorders. However, the precise underlying mechanisms have not been fully elucidated. In this study, we investigated the function of lncRNA MALAT1 in the bupivacaine-induced neurotoxicity process. MATERIALS AND METHODS: SH-SY5Y cells and neonatal mouse DRG neurons were cultured in vitro and treated with bupivacaine to establish a neurotoxicity model. Caspase3 activity and cell survival rates were detected to evaluate the function of lncRNA MALAT1. Western blotting was used to detect the expression levels of PDCD4 and cleaved-caspase-3. A dual-luciferase reporter assay was used to explore the potential binding target of lncRNA MALAT1. RESULTS: We found that the expression of lncRNA MALAT1 was upregulated upon exposure to bupivacaine. Knockdown of lncRNA MALAT1 significantly increased the cell death rates, and Caspase3 activity assays revealed that the apoptosis rates were manifestly increased in the MALAT1 downregulation group. In addition, we screened the possible target and found that miR-101-3p is the direct target of MALAT1 using a dual-luciferase reporter assay; these results suggest that lncRNA MALAT1 may function as a decoy to sponge miR-101-3p. Furthermore, we demonstrated that activation of the MALAT1/miR-101-3p/PDCD4 axis protected cells against bupivacaine treatment. CONCLUSION: We elucidated the function and mechanism of MALAT1 in bupivacaine-induced neurotoxicity. Targeting MALAT1 might provide new methods to prevent neurotoxicity.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Bupivacaína/toxicidade , MicroRNAs/metabolismo , Síndromes Neurotóxicas/etiologia , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo , Anestésicos Locais/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Gânglios Espinais/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Camundongos , MicroRNAs/genética , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Regulação para Cima/efeitos dos fármacos
15.
Int J Mol Sci ; 20(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075852

RESUMO

Lin-28 is an RNA-binding protein that is known for its role in promoting the pluripotency of stem cells. In the present study, Arabian camel Lin-28 (cLin-28) cDNA was identified and analyzed. Full length cLin-28 mRNA was obtained using the reverse transcription polymerase chain reaction (RT-PCR). It was shown to be 715 bp in length, and the open reading frame (ORF) encoded 205 amino acids. The molecular weight and theoretical isoelectric point (pI) of the cLin-28 protein were predicted to be 22.389 kDa and 8.50, respectively. Results from the bioinformatics analysis revealed that cLin-28 has two main domains: an N-terminal cold-shock domain (CSD) and a C-terminal pair of retroviral-type Cysteine3Histidine (CCHC) zinc fingers. Sequence similarity and phylogenetic analysis showed that the cLin-28 protein is grouped together Camelus bactrianus and Bos taurus. Quantitative real-time PCR (qPCR) analysis showed that cLin-28 mRNA is highly expressed in the lung, heart, liver, and esophageal tissues. Peptide mass fingerprint-mass spectrometry (PMF-MS) analysis of the purified cLin-28 protein confirmed the identity of this protein. Comparing the modeled 3D structure of cLin-28 protein with the available protein 3D structure of the human Lin-28 protein confirmed the presence of CSD and retroviral-type CCHC zinc fingers, and high similarities were noted between the two structures by using super secondary structure prediction.


Assuntos
Camelus/genética , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Regulação da Expressão Gênica , Modelos Moleculares , Peptídeos/química , Filogenia , Estrutura Secundária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo
16.
Cancer Sci ; 110(7): 2189-2199, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31066120

RESUMO

It has been well established that microRNA (miR)-143 is downregulated in human bladder cancer (BC). Recent precision medicine has shown that mutations in BC are frequently observed in FGFR3, RAS and PIK3CA genes, all of which correlate with RAS signaling networks. We have previously shown that miR-143 suppresses cell growth by inhibiting RAS signaling networks in several cancers including BC. In the present study, we showed that synthetic miR-143 negatively regulated the RNA-binding protein Musashi-2 (MSI2) in BC cell lines. MSI2 is an RNA-binding protein that regulates the stability of certain mRNAs and their translation by binding to the target sequences of the mRNAs. Of note, the present study clarified that MSI2 positively regulated KRAS expression through directly binding to the target sequence of KRAS mRNA and promoting its translation, thus contributing to the maintenance of KRAS expression. Thus, miR-143 silenced KRAS and MSI2, which further downregulated KRAS expression through perturbation of the MSI2/KRAS cascade.


Assuntos
MicroRNAs/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas de Ligação a RNA/genética , Neoplasias da Bexiga Urinária/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Transplante de Neoplasias , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regulação para Cima , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
17.
Nat Commun ; 10(1): 2266, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118463

RESUMO

How multidomain RNA-binding proteins recognize their specific target sequences, based on a combinatorial code, represents a fundamental unsolved question and has not been studied systematically so far. Here we focus on a prototypical multidomain RNA-binding protein, IMP3 (also called IGF2BP3), which contains six RNA-binding domains (RBDs): four KH and two RRM domains. We establish an integrative systematic strategy, combining single-domain-resolved SELEX-seq, motif-spacing analyses, in vivo iCLIP, functional validation assays, and structural biology. This approach identifies the RNA-binding specificity and RNP topology of IMP3, involving all six RBDs and a cluster of up to five distinct and appropriately spaced CA-rich and GGC-core RNA elements, covering a >100 nucleotide-long target RNA region. Our generally applicable approach explains both specificity and flexibility of IMP3-RNA recognition, allows the prediction of IMP3 targets, and provides a paradigm for the function of multivalent interactions with multidomain RNA-binding proteins in gene regulation.


Assuntos
Modelos Moleculares , RNA Mensageiro/metabolismo , Motivos de Ligação ao RNA/fisiologia , Proteínas de Ligação a RNA/metabolismo , Regulação da Expressão Gênica/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Ligação Proteica/fisiologia , RNA Mensageiro/química , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Técnica de Seleção de Aptâmeros , Análise de Sequência de DNA/métodos
18.
Nat Commun ; 10(1): 1960, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036859

RESUMO

Lin28-dependent oligo-uridylylation of precursor let-7 (pre-let-7) by terminal uridylyltransferase 4/7 (TUT4/7) represses let-7 expression by blocking Dicer processing, and regulates cell differentiation and proliferation. The interaction between the Lin28:pre-let-7 complex and the N-terminal Lin28-interacting module (LIM) of TUT4/7 is required for pre-let-7 oligo-uridylylation by the C-terminal catalytic module (CM) of TUT4/7. Here, we report crystallographic and biochemical analyses of the LIM of human TUT4. The LIM consists of the N-terminal Cys2His2-type zinc finger (ZF) and the non-catalytic nucleotidyltransferase domain (nc-NTD). The ZF of LIM adopts a distinct structural domain, and its structure is homologous to those of double-stranded RNA binding zinc fingers. The interaction between the ZF and pre-let-7 stabilizes the Lin28:pre-let-7:TUT4 ternary complex, and enhances the oligo-uridylylation reaction by the CM. Thus, the ZF in LIM and the zinc-knuckle in the CM, which interacts with the oligo-uridylylated tail, together facilitate Lin28-dependent pre-let-7 oligo-uridylylation.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , MicroRNAs/metabolismo , RNA Nucleotidiltransferases/química , RNA Nucleotidiltransferases/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Cristalografia por Raios X , Proteínas de Ligação a DNA/genética , Humanos , MicroRNAs/genética , Ligação Proteica , RNA Nucleotidiltransferases/genética , Proteínas de Ligação a RNA/genética
19.
Cell Mol Life Sci ; 76(17): 3283-3299, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31055645

RESUMO

Poly(ADP-ribosyl)ation (PARylation) is an important post-translational modification in which an ADP-ribose group is transferred to the target protein by poly(ADP-riboses) polymerases (PARPs). Since the discovery of poly-ADP-ribose (PAR) 50 years ago, its roles in cellular processes have been extensively explored. Although research initially focused on the functions of PAR and PARPs in DNA damage detection and repair, our understanding of the roles of PARPs in various nuclear and cytoplasmic processes, particularly in gene expression, has increased significantly. In this review, we discuss the current advances in understanding the roles of PARylation with a particular emphasis in gene expression through RNA biogenesis and processing. In addition to updating PARP's significance in transcriptional regulation, we specifically focus on how PARPs and PARylation affect gene expression, especially inflammation-related genes, at the post-transcriptional levels by modulating RNA processing and degrading. Increasing evidence suggests that PARP inhibition is a promising treatment for inflammation-related diseases besides conventional chemotherapy for cancer.


Assuntos
Poli(ADP-Ribose) Polimerases/genética , RNA/metabolismo , Transporte Ativo do Núcleo Celular , Cromatina/metabolismo , Regulação da Expressão Gênica , Humanos , Inflamação/metabolismo , Inflamação/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Poliadenilação , RNA/genética , Processamento de RNA , Proteínas de Ligação a RNA/metabolismo
20.
BMC Complement Altern Med ; 19(1): 91, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035975

RESUMO

BACKGROUND: The extract of Celastrus orbiculatus (COE) have been studied for anti-Helicobacter pylori (H. pylori) activity and anti-cancer effects in vitro and in vivo. However, the molecular mechanism by which COE inhibits H. pylori-induced inflammatory response has not been fully elucidated so far. METHODS: The effects of COE on viability, morphological changes, inflammatory cytokine secretion, protein and mRNA expression were analyzed by MTT assay, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, western blot and real-time PCR (RT-PCR), respectively. The methylation level of programmed cell death 4 (PDCD4) promoter was investigated by methylation-specific PCR. (MSP) . RESULTS: COE effectively inhibited the H.pylori-induced inflammatory response by regulating epithelial-mesenchymal transition (EMT). The methylation level of PDCD4 promoter was suppressed by COE, which increased the expression ofPDCD4. Moreover, COE could inhibit microRNA-21 (miR-21) expression, as shown by an enhancement of its target gene PDCD4. Furthermore, both miR-21 over-expression and PDCD4 silencing attenuated the anti-inflammatory effect. of COE. CONCLUSIONS: COE inhibits H. pylori induced inflammatory response through regulating EMT, correlating with inhibition of miR-21/PDCD4 signal pathways in gastric epithelial cells.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Celastrus/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Helicobacter pylori , MicroRNAs/metabolismo , Extratos Vegetais/farmacologia , Proteínas de Ligação a RNA/metabolismo , Anti-Inflamatórios/farmacologia , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Citocinas/análise , Citocinas/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Mucosa Gástrica/citologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Transdução de Sinais/efeitos dos fármacos
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