RESUMEN
BACKGROUND: Atrial fibrillation (AF) is the most common cardiac heterogeneous rhythm disorder. It represents a major cause of mortality and morbidity, mainly related to embolic events and heart failure. Mechanisms of AF are complex and remain incompletely understood. Recent evidence suggests exosomes are membrane-coated objects released by many cell-types. Their presence in body fluids and the variable surface composition and content render them attractive as a mechanism for potential biomarkers. However, the content of serum exosomes of AF patients has not been fully delineated. METHODS: In this work, the serum exosomes from AF patients and healthy donors were used to compare changes in the exosome protein content. Exosomes were isolated from serum of AF patients and healthy donors and their purity was confirmed by Western blotting assays and transmission electron microscopy (TEM). Label-free LC-MS/MS quantitative proteomic analysis was applied to analyze protein content of serum exosomes. RESULTS: A total of 440 exosomal protein groups were identified, differentially expressed proteins were filtrated with fold change ≥ 2.0 (AF/controls protein abundance ratio ≥ 2 or ≤ 0.5) and p value less than 0.05 (p < 0.05), significantly changed in abundance group contains 39 elevated proteins and 18 reduced proteins, while consistent presence/absence expression profile group contains 40 elevated proteins and 75 reduced proteins. Bioinformatic analysis of differential exosomal proteins confirmed the significant enrichment of components involved in the anticoagulation, complement system and protein folding. Parallel-Reaction Monitoring Relative Quantitative Analysis (PRM) further suggested that AF related to complement system and protein folding. CONCLUSIONS: These results revealed the composition and potential function of AF serum exosomes, thus providing a new perspective on the complement system and protein folding to AF.
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As the most common malignancy, lung cancer is characterised by high rates of occurrence and mortality. Although circular RNAs (circRNAs) are known to act as important regulators in cancer, their role in lung cancer remains poorly understood. In this study, circ_GRHPR expression was found to be significantly upregulated in the serum of five patients with non-small cell lung cancer (NSCLC), compared to that in healthy controls. It is expressed at high levels in NSCLC cell lines, as revealed by qRT-PCR analysis. Functionally, we demonstrated that circ_GRHPR promotes NSCLC proliferation and invasion in vitro and in vivo by cell proliferation, transwell, cell cycle, and tumour-forming assays. Mechanistically, RNA pull-down and RNA immunoprecipitation assays showed that circ_GRHPR interacts with the RNA-binding protein poly(rC)-binding protein 2 (PCBP2) and regulates its subcellular localisation by forming the circ_GRHPR/PCBP2 complex, localizing PCBP2 mainly in the cytoplasm and reducing the proportion found in the nucleus. Furthermore, we demonstrated that four-and-a-half LIM-only protein 3 (FHL3) is a tumour-stimulating factor in NSCLC that interacts with and is influenced by PCBP2. Circ_GRHPR increased FHL3 expression in the nucleus of NSCLC cells by decreasing PCBP2 expression therein and promoting the proliferation and invasion of NSCLC cells. Therefore, our study identified that circ_GRHPR promotes NSCLC proliferation and invasion, providing a possible explanation for its mechanism of action.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Células A549 , Proliferación Celular , Humanos , Masculino , ARN Circular , Proteínas de Unión al ARNRESUMEN
Estrogen/ERα signaling is critical for breast cancer progression and therapeutic treatments. Thus, identifying new regulators of this pathway will help to develop new therapeutics to overcome chemotherapy resistance of the breast cancer cells. Here, we report Ajuba directly interacts with ERα to potentiate ERα target gene expression, and biologically Ajuba promotes breast cancer cell growth and contributes to tamoxifen resistance of these cells. Ajuba constitutively binds the DBD and AF2 regions of ERα, and these interactions can be markedly enhanced by estrogen treatment. Mechanistically, Ajuba recruits DBC1 and CBP/p300 and forms a ternary complex to co-activate ERα transcriptional activity and concomitantly enhances ERα acetylation. Moreover, components of this complex can be found at endogenous promoters containing functional ERα responsive elements. Taken together, these data demonstrate that Ajuba functions as a novel co-activator of ERα and that Ajuba/DBC1/CBP/p300 ternary complex may be a new target for developing therapeutics to treat breast cancer.
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Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/química , Receptor alfa de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas con Dominio LIM/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Factores de Transcripción p300-CBP/metabolismo , Acetilación , Neoplasias de la Mama/patología , Proteínas de Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Receptor alfa de Estrógeno/agonistas , Estrógenos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas con Dominio LIM/genética , Proteínas del Tejido Nervioso , Unión Proteica/efectos de los fármacos , Tamoxifeno/antagonistas & inhibidores , Tamoxifeno/farmacología , Transcripción Genética/efectos de los fármacosRESUMEN
MicroRNAs (miRNAs) are a class of endogenous, evolutionarily conserved small non-coding RNA molecules that mediate the posttranscriptional process of target gene, leading to translational repression or degradation of target mRNAs. A series of studies have indicated that miRNAs play an important role in tumor initiation, development and progression. In this study, we found that down regulation of miR-598 was a frequent event in CRC tissues compared to the paracarcinoma tissues. And the study demonstrated that miR-598 was implicated in CRC metastasis. Transwell migration assay revealed that elevated miR-598 expression reduces CRC cell migration. Moreover, our study showed that suppression of miR-598 expression induces CRC cell epithelialmesenchymal transition(EMT) and overexpression of miR-598 inhibits CRC cell EMT. In addition, bioinformatics target prediction identified JAG1 as a putative target of miR-598. Knockdown of miR-598 was shown to upregulate JAG1 expression. Furthermore, overexpression of miR-598 suppressed the expression of JAG1. Consistent results were also obtained when the regulation of JAG1 expression by miR-598 was further specified in CRC tissues. Moreover, overexpression of JAG1 induces epithelialmesenchymal transition(EMT) and promotes the metastasis of CRC cells. Decreased Notch2 expression suppresses CRC cells metastasis and EMT. Together, these results indicate that miR-598 is a novel regulator of colorectal cancer metastasis. Our data suggest miR-598 is implicated in regulating Epithelial-mesenchymal transitions by directly suppressing its downstream target gene JAG1 to inactivate Notch signaling pathway.
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Movimiento Celular , Neoplasias Colorrectales/prevención & control , Transición Epitelial-Mesenquimal , Proteína Jagged-1/antagonistas & inhibidores , Receptor Notch2/antagonistas & inhibidores , Animales , Apoptosis , Western Blotting , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Técnica del Anticuerpo Fluorescente , Regulación Neoplásica de la Expresión Génica , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs , Metástasis de la Neoplasia , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor Notch2/genética , Receptor Notch2/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Understanding immune phenotypes and human gastric disease in situ requires an approach that leverages multiplexed immunohistochemistry (mIHC) with multispectral imaging to facilitate precise image analyses. METHODS: We developed a novel 4-color mIHC assay based on tyramide signal amplification that allowed us to reliably interrogate immunologic checkpoints, including programmed death-ligand 1 (PD-L1), cytotoxic T cells (CD8+T) and regulatory T cells (Foxp3), in formalin-fixed, paraffin-embedded tissues of various human gastric diseases. By observing cell phenotypes within the disease tissue microenvironment, we were able to determine specific co-localized staining combinations and various measures of cell density. RESULTS: We found that PD-L1 was expressed in gastric ulcer and in tumor cells (TCs), as well as in tumor-infiltrating immune cells (TIICs), but not in normal gastric mucosa or other gastric intraepithelial neoplastic tissues. Furthermore, we found no significant reduction in CD8+T cells, whereas the ratio of CD8+T:Foxp3 cells and CD8+T:PD-L1 cells was suppressed in tumor tissues and elevated in adjacent normal tissues. An unsupervised hierarchical analysis also identified correlations between CD8+T and Foxp3+ tumor-infiltrating lymphocyte (TIL) densities and average PD-L1 levels. Three main groups were identified based on the results of CD8+T:PD-L1 ratios in gastric tumor tissues. Furthermore, integrating CD8+T:Foxp3 ratios, which increased the complexity for immune phenotype status, revealed 6-7 clusters that enabled the separation of gastric cancer patients at the same clinical stage into different risk-group subsets. CONCLUSIONS: Characterizing immune phenotypes in human gastric disease tissues via multiplexed immunohistochemistry may help guide PD-L1 clinical therapy. Observing unique disease tissue microenvironments can improve our understanding of immune phenotypes and cell interactions within these microenvironments, providing the ability to predict safe responses to immunotherapies.
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Inmunohistoquímica/métodos , Gastropatías/inmunología , Gastropatías/patología , Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos/inmunología , Factores de Transcripción Forkhead/metabolismo , Humanos , FenotipoRESUMEN
Focal adhesion kinase (FAK) regulates cell adhesion, migration, proliferation, and survival. We identified a novel splicing mutant, FAK-Del33 (exon 33 deletion, KF437463), in both breast and thyroid cancers through colony sequencing. Considering the low proportion of mutant transcripts in samples, this mutation was detected by TaqMan-MGB probes based qPCR. In total, three in 21 paired breast tissues were identified with the FAK-Del33 mutation, and no mutations were found in the corresponding normal tissues. When introduced into a breast cell line through lentivirus infection, FAK-Del33 regulated cell motility and migration based on a wound healing assay. We demonstrated that the expression of Tyr397 (main auto-phosphorylation of FAK) was strongly increased in FAK-Del33 overexpressed breast tumor cells compared to wild-type following FAK/Src RTK signaling activation. These results suggest a novel and unique role of the FAK-Del33 mutation in FAK/Src signaling in breast cancer with significant implications for metastatic potential.
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Neoplasias de la Mama/enzimología , Neoplasias de la Mama/genética , Análisis Mutacional de ADN , Exones/genética , Proteína-Tirosina Quinasas de Adhesión Focal/genética , Mutación/genética , Femenino , Eliminación de Gen , Humanos , Células Tumorales CultivadasRESUMEN
OBJECTIVE: To conduct molecular prevalence and genetic polymorphism analysis of 24 Swine Farm associated C. difficile ST11 strains, in addition to other representative sequenced ST strains. METHODS: The collected C. difficile strains underwent whole genome sequencing and bioinformatic analysis using the illumina NovaSeq platform, SPAdes, Prokka, MOB-suite, and FastTree. Virulence and antibiotic resistance genes were identified through NCBI Pathogen Database. Cytotoxicity tests were conducted on HT-29 cells and Vero cells to verify the function of toxin A and toxin B. RESULTS: The most prevalent resistance genes in ST11 were found to be against ß-lactamases, aminoglycosides, and tetracycline. A C. difficile isolate (strain 27) with tcdA deletion and high antibiotic resistance genes was far apart from other swine farm associated ST11 isolates in the phylogenetic branch. The remarkable genetic similarity between animal and human C. difficile strains suggests potential transmission of ST11 strains between animals and humans. The plasmid replicon sequences repUS43 were identified in all ST11 strains except one variant (strain 27), and 91.67% (22/24) of these were assessed by MOB-typer as having mobilizable plasmids. CONCLUSION: Swine farm associated C. difficile ST11 carried fewer virulence genes than ST11 strains collected from NCBI database. It is critical to monitor the evolution of C. difficile strains to understand their changing characteristics, host-switching, and develop effective control and prevention strategies.
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Clostridioides difficile , Infecciones por Clostridium , Granjas , Filogenia , Enfermedades de los Porcinos , Animales , Clostridioides difficile/genética , Clostridioides difficile/clasificación , Porcinos , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/epidemiología , Infecciones por Clostridium/veterinaria , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/epidemiología , Secuenciación Completa del Genoma , Antibacterianos/farmacología , Virulencia/genética , Células Vero , Humanos , Chlorocebus aethiops , Farmacorresistencia Bacteriana/genética , Plásmidos/genética , Factores de Virulencia/genéticaRESUMEN
Carbapenem-resistant Escherichia coli (CREC) poses a severe global public health risk. This study reveals the worldwide geographic spreading patterns and spatiotemporal distribution characteristics of resistance genes in 7918 CREC isolates belonging to 497 sequence types (ST) and originating from 75 countries. In the last decade, there has been a transition in the prevailing STs from highly virulent ST131 and ST38 to higher antibiotic-resistant ST410 and ST167. The rise of multi-drug resistant strains of CREC carrying plasmids with extended-spectrum beta-lactamase (ESBL) resistance genes could be attributed to three important instances of host-switching events. The spread of CREC was associated with the changing trends in blaNDM-5, blaKPC-2, and blaOXA-48, as well as the plasmids IncFI, IncFII, and IncI. There were intercontinental geographic transfers of major CREC strains. Various crucial transmission hubs and patterns have been identified for ST131 in the United Kingdom, Italy, the United States, and China, ST167 in India, France, Egypt, and the United States, and ST410 in Thailand, Israel, the United Kingdom, France, and the United States. This work is valuable in managing CREC infections and preventing CREC occurrence and transmission inside healthcare settings and among diverse hosts.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Escherichia coli/genética , Salud Pública , Antibacterianos , Carbapenémicos/farmacologíaRESUMEN
The widespread use of azoles has led to increasing azole resistance among Candida albicans strains. One mechanism of azole resistance involves point mutations in the ERG11 gene, which encodes the target enzyme (cytochrome P450 lanosterol 14α-demethylase). In the present study, we amplified and sequenced the ERG11 gene of 23 C. albicans clinical isolates. Seventeen mutations encoding distinct amino acid substitutions were found, of which seven (K143Q, Y205E, A255V, E260V, N435V, G472R, and D502E) were novel. We further verified the contribution of the amino acid substitutions to azole resistance using site-directed mutagenesis of the ERG11 gene to recreate these mutations for heterologous expression in Saccharomyces cerevisiae. We observed that substitutions A114S, Y132H, Y132F, K143R, Y257H, and a new K143Q substitution contributed to significant increases (â§fourfold) in fluconazole and voriconazole resistance; changes in itraconazole resistance were not significant (â¦twofold).
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Antifúngicos/farmacología , Azoles/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/genética , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica , Mutación Missense , Sustitución de Aminoácidos , Candida albicans/aislamiento & purificación , Candidiasis/microbiología , Sistema Enzimático del Citocromo P-450/metabolismo , Análisis Mutacional de ADN , ADN de Hongos/química , ADN de Hongos/genética , Humanos , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Análisis de Secuencia de ADNRESUMEN
CD166/ALCAM plays an important role in tumor aggression and progression as well as protecting cancer cells against apoptosis and autophagy. However, the mechanism by which pro-cell death signals control CD166 expression remains unclear. Here we show that following serum deprivation (SD), upregulation of CD166 protein is shorter than that of CD166 mRNA. Molecular analysis revealed both CD166 and miR-9-1 as two novel NF-κB target genes in hepatoma cells. In vivo activation and translocation of the NF-κB P50/P65 hetero-dimer into the nucleus following the phosphorylation and accompanied degradation of its inhibitor, IκBα, contributes to efficient transcription of both genes following SD. We show that following serum starvation, delayed up-regulation of miR-9 represses translation of CD166 protein through its target sites in the 3'-UTR of CD166 mRNA. We also propose that miR-9 promotes cell migration largely due to inhibition of CD166. Collectively, the study elucidates a novel negative auto-regulatory loop in which NF-κB mediates differential regulation of CD166 after SD.
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Molécula de Adhesión Celular del Leucocito Activado/genética , Regulación de la Expresión Génica , MicroARNs/metabolismo , Subunidad p50 de NF-kappa B/metabolismo , Factor de Transcripción ReIA/metabolismo , Molécula de Adhesión Celular del Leucocito Activado/biosíntesis , Línea Celular Tumoral , Movimiento Celular , Medio de Cultivo Libre de Suero , Dimerización , Elementos de Facilitación Genéticos , Retroalimentación Fisiológica , Humanos , MicroARNs/genética , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Regulación hacia ArribaRESUMEN
An increasing body of evidence has suggested that reprogrammed metabolism plays a critical role in the progression of pancreatic ductal adenocarcinoma (PDAC) by affecting the tumor and stromal cellular components in the tumor microenvironment (TME). By analyzing the KRAS pathway and metabolic pathways, we found that calcium and integrin-binding protein 1 (CIB1) corresponded with upregulation of glucose metabolism pathways and was associated with poor prognosis in patients with PDAC from The Cancer Genome Atlas (TCGA). Elevated CIB1 expression combined with upregulated glycolysis, oxidative phosphorylation (Oxphos), hypoxia pathway activation, and cell cycle promoted PDAC tumor growth and increased tumor cellular com-ponents. Furthermore, we confirmed the mRNA overexpression of CIB1 and co-expression of CIB1 and KRAS mutation in cell lines from the Expression Atlas. Subsequently, immunohistochemistry staining from the Human Protein Atlas (HPA) showed that high expression of CIB1 in tumor cells was associated with an increased tumor compartment and reduced stromal cellular abundance. Furthermore, using multiplexed immunohistochemistry (mIHC), we verified that low stromal abundance was correlated with low infiltration of CD8+ PD-1- T cells which led to suppressed anti-tumor immunity. Overall, our findings identify CIB1 as a metabolic pathway-mediated factor for the restriction of immune cell infiltration in the stromal compartment of PDAC and highlight the potential value of CIB1 as a prognostic biomarker involved in metabolic reprogramming and immune modulation.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Calcio/metabolismo , Carcinoma Ductal Pancreático/patología , Glucosa , Integrinas/metabolismo , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Microambiente Tumoral , Neoplasias PancreáticasRESUMEN
Inflammasome activity is important for the immune response and is instrumental in numerous clinical conditions. Here we identify a mechanism that modulates the central Caspase-1 and NLR (Nod-like receptor) adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD). We show that the function of ASC in assembling the inflammasome is controlled by its modification with SUMO (small ubiquitin-like modifier) and identify that the nuclear ZBTB16 (zinc-finger and BTB domain-containing protein 16) promotes this SUMOylation. The physiological significance of this activity is demonstrated through the reduction of acute inflammatory pathogenesis caused by a constitutive hyperactive inflammasome by ablating ZBTB16 in a mouse model of Muckle-Wells syndrome. Together our findings identify an further mechanism by which ZBTB16-dependent control of ASC SUMOylation assembles the inflammasome to promote this pro-inflammatory response.
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Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Ratones , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Caspasa 1/metabolismo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Unión Proteica , SumoilaciónRESUMEN
TIGAR expression resulted in down-regulation of glycolysis, reduction of intracellular levels of reactive oxygen species, and protection from apoptosis. Despite biological importance, its promoter has not yet been characterized. In this study, we characterized that transcription factor SP1 plays a pivotal role for basal activity of TIGAR promoter. By 5'RACE, the transcription start site was identified locating at 134 bp upstream of the translation initiation site. Different portions of 5'-flanking and 5'-untranslated regions were fused to a luciferase reporter gene to create reporter plasmids, and constructs were transiently transfected into HepG2, Bel-7402, and Smmc-7721 cell lines for luciferase analysis. A minimal region -56/-4 bearing a SP1-binding site was characterized and plays a vital role. Data from electrophoretic mobility shift assay and chromatin immunoprecipitation showed that SP1 can interact with the SP1-binding site within TIGAR promoter in vitro and in vivo. Conclusively, SPl is indispensable for basal activity of TIGAR promoter.
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Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Hepáticas/genética , Regiones Promotoras Genéticas , Factor de Transcripción Sp1/fisiología , Proteínas Reguladoras de la Apoptosis , Sitios de Unión , Línea Celular Tumoral , Humanos , Monoéster Fosfórico Hidrolasas , Factor de Transcripción Sp1/genética , Sitio de Iniciación de la TranscripciónRESUMEN
Long non-coding RNA (lncRNA), highly up-regulated in liver cancer (HULC) plays an important role in tumorigenesis. Depletion of HULC resulted in a significant deregulation of several genes involved in liver cancer. Although up-regulation of HULC expression in hepatocellular carcinoma has been reported, the molecular mechanisms remain unknown. In this study, we used in vivo and in vitro approaches to characterize cancer-dependent alterations in the chromatin organization and find a CREB binding site (encompassing from -67 to -53 nt) in the core promoter. Besides, we also provided evidence that PKA pathway may involved in up-regulation of HULC. Furthermore, we demonstrated HULC may act as an endogenous 'sponge', which down-regulates a series of microRNAs (miRNAs) activities, including miR-372. Inhibition of miR-372 leads to reducing translational repression of its target gene, PRKACB, which in turn induces phosphorylation of CREB. Over-expression of miR-372 decreases the association of CREB with the proximal promoter, followed by the dissociation of P300, resulting in a change of the histone 'code', such as in deacetylation and methylation. The study elucidates that fine tuning of HULC expression is part of an auto-regulatory loop in which it's inhibitory to expression and activity of miR-372 allows lncRNA up-regulated expression in liver cancer.
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Carcinoma Hepatocelular/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , MicroARNs/metabolismo , ARN no Traducido/genética , Sitios de Unión , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Cromatina/química , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Regiones Promotoras Genéticas , ARN no Traducido/biosíntesis , Factores de Transcripción/metabolismo , Sitio de Iniciación de la Transcripción , Transcripción Genética , Activación Transcripcional , Regulación hacia ArribaAsunto(s)
Proteínas de Unión al Calcio/metabolismo , Carcinoma Hepatocelular/metabolismo , Citoesqueleto/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Unión al Calcio/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Microscopía Confocal , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The authors performed a systematic review and meta-analysis of associations of the x-ray repair cross-complementing 1 gene (XRCC1) single nucleotide polymorphisms (SNPs) Arg194Trp, Arg280His, and Arg399Gln with gastric cancer risk, based on eligible studies retrieved from electronic databases for the period January 2000-December 2009. Ultimately, 12, 6, and 3 studies were found to be eligible for meta-analyses of Arg399Gln, Arg194Trp, and Arg280His, respectively. Regrouping was adopted in accordance with the most probably appropriate genetic models. Potential sources of heterogeneity were sought out. For overall gastric cancer, the pooled odds ratios for Arg399Gln, Arg194Trp, and Arg280His were 1.04 (95% confidence interval (CI): 0.90, 1.20; P = 0.572), 0.83 (95% CI: 0.68, 1.01; P = 0.059), and 1.18 (95% CI: 0.92, 1.50; P = 0.194), respectively. After stratification of the Arg399Gln SNP data by anatomic type (cardia vs. noncardia), the pooled odds ratio was 1.07 (95% CI: 0.84, 1.37; P = 0.568). The authors conclude that the 3 SNPs evaluated are not associated with risk of gastric cancer. The Arg399Gln SNP is not associated with the cardia type of gastric cancer. Evidently, the heterogeneity regarding the Arg399Gln SNP across studies is not explained by ethnicity, genotyping technique, sample size, or date of publication.
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Proteínas de Unión al ADN/genética , Polimorfismo de Nucleótido Simple , Neoplasias Gástricas/genética , Distribución de Chi-Cuadrado , Intervalos de Confianza , Predisposición Genética a la Enfermedad , Genoma Humano , Genotipo , Humanos , Oportunidad Relativa , Riesgo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos XRESUMEN
There is a growing evidence that regucalcin (RGN) plays a multifunctional role in liver cancer cells. Previous reports showed that the presence of phorbol 12-myristate 13-acetate (PMA) caused a significant increase in RGN mRNA expression and promoter activity in rat hepatoma cells. In this study, we confirmed that human RGN is also up-regulated by PMA treatment independent of translation, and we identified the mechanism by which PMA up-regulates the expression of human RGN via driving SP1 away from a SP1 motif located within -188/-180 of the promoter in HepG2 cells. Overexpression of SP1 dramatically reduces PMA-induced up-regulation of both internal expression of mRNA and promoter activity, whereas knockdown of SP1 has the opposite effect. Therefore, the present study delineates the fundamental elements in the promoter which will be helpful in the future studies on the regulation of RGN expression in liver cancer.
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Proteínas de Unión al Calcio/genética , Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/genética , Factor de Transcripción Sp1/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Regulación hacia Arriba/efectos de los fármacos , Secuencia de Bases , Proteínas de Unión al Calcio/metabolismo , Inmunoprecipitación de Cromatina , Regulación de la Expresión Génica , Genes Reporteros , Células Hep G2 , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas , Luciferasas de Luciérnaga/biosíntesis , Luciferasas de Luciérnaga/genética , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Unión Proteica , Factor de Transcripción Sp1/genéticaRESUMEN
BACKGROUND AND PURPOSE: Vascular endothelial growth factor (VEGF) plays a key role in the development of cerebral infarction as a major mediator of angiogenesis. The aim of this study was to investigate whether the VEGF gene polymorphisms were associated with the risks of acute cerebral infarction. METHODS: We examined the distribution of three single nucleotide polymorphisms (SNPs), -1154G/A, 936C/T and -2578C/A, in the promoter and coding region of the VEGF gene in DNA samples from 147 Chinese patients with acute cerebral infarction and 131 control subjects. RESULTS: There was no significant difference in allele and genotype distributions of -1154G/A, 936C/T and -2578C/A with the risk of acute cerebral infarction when compared with controls. However, haplotype analysis from the above-mentioned three polymorphisms showed that haplotype ACC was significantly lower in patients with acute cerebral infarction (0.020) than in controls (0.054) (p = 0.034). CONCLUSIONS: These data suggested that the -1154/, 936/ and -2578/ ACC haplotype was associated with the risk of acute cerebral infarction with an OR of 0.361, and it may reduce the risk of acute cerebral infarction through the regulation of VEGF expression.
Asunto(s)
Infarto Cerebral/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Factor A de Crecimiento Endotelial Vascular/genética , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Infarto Cerebral/diagnóstico , Distribución de Chi-Cuadrado , China/epidemiología , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética/métodos , Genotipo , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: To establish experimental models for tumor neovascularization and to apply quantitative digital imaging analysis in the study. METHODS: An endothelial tube formation model was established by human umbilical vein endothelial cells (HUVECs). A vasculogenic mimicry model was established by SGC-7901 gastric cancer cell line. Fertilized eggs were used to establish a chorioallantoic membrane angiogenesis model. Using gene transfection experiment, IRX1 tumor suppressor gene was chosen as a therapeutic target. Image Pro Plus (IPP) analysis software was used for digital vascular images analysis with parameters including points, lines, angles and integral absorbance (IA) for the tubular formation or vasculogenic mimicry. RESULTS: Digital image analysis by IPP showed that HUVEC tubular formation was significantly inhibited in IRX1 transfectant, compared with controls. The tubular numbers in three groups were 12.80 +/- 3.83, 29.00 +/- 5.34 and 28.20 +/- 4.32 (P<0.01). The connection points of tubules in three groups were 13.20 +/- 2.59, 25.00 +/- 2.24 and 24.60 +/- 3.21 (P<0.01). The tubular lengths of three groups were (821.5 +/- 12.5), (930.9 +/- 13.5) and (948.4 +/- 18.1) microm (P=0.022). The IA values of PAS stain in three groups were 3606 +/- 363, 14 200 +/- 1251 and 15 043 +/- 1220 (P<0.01). In chick chorioallantoic membrane model, the angular numbers of tubules in three groups were 6.41 +/- 2.60, 10.27 +/- 2.65 and 9.18 +/- 1.99 (P<0.01). CONCLUSIONS: The endothelial tube formation model, vasculogenic mimicry model and chorioallantoic membrane angiogenesis model are useful for gene therapy and drug screening with targeting neoplastic vascularization. Professional image analysis software may greatly facilitate the quantitative analysis of tumor neovascularization.