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1.
Free Radic Biol Med ; 224: 50-61, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39147072

RESUMEN

Hydrogen-rich water (HRW) is a beverage containing a high concentration of hydrogen that has been researched for its antioxidant, anti-apoptotic, and anti-inflammatory properties in asthma. This study investigates the potential therapeutic impact of HRW on the gut-lung axis. Using 16S rRNA and serum metabolomics, we examined changes in gut microbiota and serum metabolites in asthmatic mice after HRW intervention, followed by validation experiments. The findings revealed that HRW influenced gut microbiota by increasing Ligilactobacillus and Bifidobacterium abundance and enhancing the presence of indole-3-acetic acid (IAA), a microbially derived serum metabolite. Both in vivo and in vitro experiments showed that HRW's protective effects against airway inflammation in asthmatic mice may be linked to the gut microbiota, with IAA potentially playing a role in reducing asthmatic airway inflammation through the aryl hydrocarbon receptors (AhR) signaling pathway. In summary, HRW can modify gut microbiota, increase Bifidobacterium abundance, elevate microbial-derived IAA levels, and activate AhR, which could potentially alleviate inflammation in asthma.

2.
PLoS Negl Trop Dis ; 18(7): e0012291, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39012845

RESUMEN

BACKGROUND: Understanding and mapping the distribution of sandflies and sandfly-associated pathogens (SAPs) is crucial for guiding the surveillance and control effort. However, their distribution and the related risk burden in China remain poorly understood. METHODS: We mapped the distribution of sandflies and SAPs using literature data from 1940 to 2022. We also mapped the human visceral leishmaniasis (VL) cases using surveillance data from 2014 to 2018. The ecological drivers of 12 main sandfly species and VL were identified by applying machine learning, and their distribution and risk were predicted in three time periods (2021-2040, 2041-2060, and 2061-2080) under three scenarios of climate and socioeconomic changes. RESULTS: In the mainland of China, a total of 47 sandfly species have been reported, with the main 12 species classified into three clusters according to their ecological niches. Additionally, 6 SAPs have been identified, which include two protozoa, two bacteria, and two viruses. The incidence risk of different VL subtypes was closely associated with the distribution risk of specific vectors. The model predictions also revealed a substantial underestimation of the current sandfly distribution and VL risk. The predicted areas affected by the 12 major species of sandflies and the high-risk areas for VL were found to be 37.9-1121.0% and 136.6% larger, respectively, than the observed range in the areas. The future global changes were projected to decrease the risk of mountain-type zoonotic VL (MT-ZVL), but anthroponotic VL (AVL) and desert-type zoonotic VL (DT-ZVL) could remain stable or slightly increase. CONCLUSIONS: Current field observations underestimate the spatial distributions of main sandfly species and VL in China. More active surveillance and field investigations are needed where high risks are predicted, especially in areas where the future risk of VL is projected to remain high or increase.


Asunto(s)
Insectos Vectores , Psychodidae , Animales , China/epidemiología , Psychodidae/parasitología , Humanos , Insectos Vectores/parasitología , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/transmisión , Distribución Animal
3.
J Cancer ; 15(8): 2431-2441, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38495492

RESUMEN

Purpose: Bladder cancer (BC) is one of the top 10 common tumors in the world. It has been reported that microbiota can colonize tissues and play important roles in tumorigenesis and progression. However, the current understanding of microorganisms in the BC tissue microenvironment remains unclear. Methods: In this study, we integrated the RNA-seq data of 479 BC tissue samples from seven datasets combined with a range of bioinformatics tools to explore the landscape of microbiome in the BC tissue microenvironment. Results: The pan-microbiome was estimated to surpass 1,400 genera. A total of seven core microbiota (Bacillus, Corynebacterium, Cutibacterium, Escherichia, Halomonas, Pasteurella, and Streptomyces) were identified. Among them, Bacillus was widely distributed in all datasets with a high relative abundance (10.11% of all samples on average). Moreover, some biological factors, including tissue source and tumor grade, were found significant effects on the microbial composition of the bladder tissue. Pseudomonas, Porphyrobacter, and Acinetobacter were enriched in tumor tissues, while Mycolicibacterium and Streptomyces were enriched in patients who showed durable response to BCG therapy. In addition, we established microbial co-occurrence networks and found that the BCG therapy may attenuate the microbiological interactions. Conclusions: This study clearly provided a microbial landscape of the BC tissue microenvironment, which was important for exploring the interactions between microorganisms and BC tissues. The identified specific taxa might be potential biomarkers for BC.

4.
Global Health ; 19(1): 58, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37592305

RESUMEN

BACKGROUND: Outbreaks of monkeypox have been ongoing in non-endemic countries since May 2022. A thorough assessment of its global zoonotic niche and potential transmission risk is lacking. METHODS: We established an integrated database on global monkeypox virus (MPXV) occurrence during 1958 - 2022. Phylogenetic analysis was performed to examine the evolution of MPXV and effective reproductive number (Rt) was estimated over time to examine the dynamic of MPXV transmissibility. The potential ecological drivers of zoonotic transmission and inter-regional transmission risks of MPXV were examined. RESULTS: As of 24 July 2022, a total of 49 432 human patients with MPXV infections have been reported in 78 countries. Based on 525 whole genome sequences, two main clades of MPXV were formed, of which Congo Basin clade has a higher transmissibility than West African clade before the 2022-monkeypox, estimated by the overall Rt (0.81 vs. 0.56), and the latter significantly increased in the recent decade. Rt of 2022-monkeypox varied from 1.14 to 4.24 among the 15 continuously epidemic countries outside Africa, with the top three as Peru (4.24, 95% CI: 2.89-6.71), Brazil (3.45, 95% CI: 1.62-7.00) and the United States (2.44, 95% CI: 1.62-3.60). The zoonotic niche of MPXV was associated with the distributions of Graphiurus lorraineus and Graphiurus crassicaudatus, the richness of Rodentia, and four ecoclimatic indicators. Besides endemic areas in Africa, more areas of South America, the Caribbean States, and Southeast and South Asia are ecologically suitable for the occurrence of MPXV once the virus has invaded. Most of Western Europe has a high-imported risk of monkeypox from Western Africa, whereas France and the United Kingdom have a potential imported risk of Congo Basin clade MPXV from Central Africa. Eleven of the top 15 countries with a high risk of MPXV importation from the main countries of 2022-monkeypox outbreaks are located at Europe with the highest risk in Italy, Ireland and Poland. CONCLUSIONS: The suitable ecological niche for MPXV is not limited to Africa, and the transmissibility of MPXV was significantly increased during the 2022-monkeypox outbreaks. The imported risk is higher in Europe, both from endemic areas and currently epidemic countries. Future surveillance and targeted intervention programs are needed in its high-risk areas informed by updated prediction.


Asunto(s)
Mpox , Humanos , Mpox/epidemiología , Filogenia , Brotes de Enfermedades , Estudios Retrospectivos , Brasil
5.
Small ; 19(35): e2301288, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37178409

RESUMEN

Metal aerogels (MAs) are emerging porous materials displaying unprecedented potential in catalysis, sensing, plasmonic technologies, etc. However, the lack of efficient regulation of their nano-building blocks (NBBs) remains a big hurdle that hampers the in-depth investigation and performance enhancement. Here, by harmonizing composition and ligand effects, Pt- and Bi-based single- and bimetallic aerogels bearing NBBs of controlled dimensions and shapes are obtained by facilely tuning the metal precursors and the applied ligands. Particularly, by further modulating the electronic and optic properties of the aerogels via adjusting the content of the catalytically active Pt component and the semiconducting Bi component, both the electrocatalytic and photoelectrocatalytic performance of the Pt-Bi aerogels can be manipulated. In this light, an impressive catalytic performance for electro-oxidation of methanol is acquired, marking a mass activity of 6.4-fold higher under UV irradiation than that for commercial Pt/C. This study not only sheds light on in situ manipulating NBBs of MAs, but also puts forward guidelines for crafting high-performance MAs-based electrocatalysts and photoelectrocatalysts toward energy-related electrochemical processes.

6.
Oncotarget ; 12(4): 366-378, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33659047

RESUMEN

The effects and mechanisms of folic acid (FA) as a chemopreventive agent for tumorigenesis of hepatocellular carcinoma (HCC) remain unclear. In this study, the QSG-7701, a human normal liver cell line, was cultured in different FA levels (High, Normal or No) for 6 months. Then, the biological characteristics, the expression of main stem cell-like genes or epithelial-mesenchymal transition (EMT) related genes and the tumorigenicity in vivo of cells cultured in different treatment groups were detected. Our results showed that No FA improved the malignant transformation of cells but High FA depressed the malignant transformation. Meanwhile, cells in different treatment groups were mapped by transcriptome sequencing. Then the relativity of increased LCN2 and decreased FA level was identified and confirmed in vitro and vivo. We also revealed that intracellular control of LCN2 would recover the effects of FA on cell proliferation, cell cycle and tumor formation in vitro and vivo. Finally, our studies displayed that increased FA level induced the down-regulation of LCN2 not by DNA hypermethylation of LCN2 promoter but by promoting the level of histone H3 lysine 9 di-methylation (H3K9Me2) in LCN2 promoter. In conclusion, our studies disclosed the chemopreventive effect of FA supplementation on hepatocarcinogenesis, which partial attributed to the inhibition of LCN2 by regulating histone methylation in promoter. Our results provide a potential mechanism of the chemoprevention of FA supplementation on tumorigenesis of HCC and may be helpful in developing treatment target against HCC.

7.
Oncotarget ; 8(31): 51387-51401, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28881655

RESUMEN

Aberrant DNA methylation patterns, which induced by folate deficiency, play important roles in tumorigenesis of colorectal cancer (CRC). Some DNA methylation alterations can also be detected in cell-free DNA (cfDNA) of patients' plasma, making cfDNA an ideal noninvasive circulating biomarker. However, exact DNA methylation alterations induced by folate deficiency in tumorigenesis of CRC and exact potential circulating cfDNA methylation biomarker are still unclear. Therefore, DNA methylation patterns of the normal human colon mucosal epithelial cell line (NCM460), cultured with normal or low folate content, were screened and the DNA hypomethylation of cystathionine-beta-synthase (CBS) promoter was further validated in vitro and vivo. Then, the correlation analysis between folate level, DNA methylation alteration in promoter and expression of CBS was carried out in vitro and vivo. Further, the methylation patterns of CBS promoter in plasma cfDNA were detected and statistically correlated with pathological parameters and clinical outcome. Our study showed that DNA hypomethylation in CBS promoter, induced by folate deficiency, would lead to up-regulation of CBS both in vitro and vivo. Patients with cfDNA hypomethylation of CBS promoter in plasma were correlated with high tumor stage and poor clinical outcome. In addition, cfDNA hypomethylation of CBS promoter in plasma was shown to be an independent prognostic factor for recurrence and cancer-related death in CRC. Our results indicated that DNA hypomethylation of CBS promoter induced by folate deficiency could serve as a potential noninvasive circulating biomarker and may be helpful in developing more effective prognostic markers for CRC.

8.
J Pathol ; 236(2): 165-74, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25727216

RESUMEN

Colorectal cancer (CRC) exhibiting MSI (microsatellite instability) represents a well-defined subtype characterized by a deficient mismatch repair pathway and typical clinico-pathological features. Our objective was to identify the entire miRNome and its molecular pathological roles in MSI CRCs. We profiled miRNA expression in MSI CRCs and compared it with MSS counterparts. Microarray and qRT-PCR analysis identified eight miRNAs that could distinguish the MSI status of CRCs. MiR-484 was the most significantly decreased miRNA in MSI CRCs, primarily mediated by the CpG island methylator phenotype. MiR-484 functions as a tumour suppressor to inhibit MSI CRC cell viability in vitro and in vivo. Moreover, miR-484 repressed CD137L expression and thereby attenuated IL-8 production by MSI CRC cells. Our results contribute to a better understanding of the roles of dysregulated miRNAs in the distinct phenotypic features of MSI CRCs and indicate an option for early diagnosis and gene therapy for these patients.


Asunto(s)
Ligando 4-1BB/metabolismo , Neoplasias Colorrectales/metabolismo , Interleucina-8/biosíntesis , MicroARNs/fisiología , Inestabilidad de Microsatélites , Ligando 4-1BB/antagonistas & inhibidores , Animales , Carcinogénesis/metabolismo , Supervivencia Celular/fisiología , Metilación de ADN/fisiología , Regulación hacia Abajo , Femenino , Estudio de Asociación del Genoma Completo , Xenoinjertos , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/metabolismo , Análisis por Micromatrices , Trasplante de Neoplasias , Células Tumorales Cultivadas
9.
Hepatology ; 61(6): 1821-31, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25627239

RESUMEN

UNLABELLED: Early-onset hepatocellular carcinoma (HCC) accounts for 15%-20% of total HCC cases in Asia, and the incidence is increasing. The low frequency of cirrhosis and poor prognosis of early-onset HCC suggests that its mechanisms may differ from late-onset HCC. Although hepatitis B virus (HBV) infection is epidemiologically associated with HCC, the role of HBV in early-onset HCC remains poorly understood. Here, we report a comparative study of HBV subgenotypes and integration in early- (≤30) and late-onset (≥70) HBV-associated HCC using a novel high-throughput viral integration detection method. We report that HBV B2 is predominantly present in early-onset HCC. HBV integration is a common phenomenon, both in early- and late-onset HCC, which favors integrating into human repeat regions. Moreover, we found a breakpoint in 8q24 located between c-Myc and plasmocytoma variant translocation 1 (PVT1), which was detected in 12.4% (14 of 113) of early-onset HCCs, but only 1.4% (2 of 145) in late-onset HCCs. HBV integrating this site results in c-MYC, PVT1, and microRNA-1204 overexpression in tumors, thereby potentially contributing to the development of early-onset HCC. CONCLUSION: HBV genotype and integration patterns may be distinct in early-onset HCC. Our results may shed light on HCC risk factors in young HBV carriers. Further studies are needed to elucidate at which time in tumor development this integration event occurs and whether it plays an important, causative role in HCC development or progression.


Asunto(s)
Carcinoma Hepatocelular/virología , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/complicaciones , Neoplasias Hepáticas/virología , Integración Viral , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/epidemiología , China/epidemiología , Femenino , Regulación Neoplásica de la Expresión Génica , Genoma Viral , Genotipo , Humanos , Neoplasias Hepáticas/epidemiología , Masculino , Adulto Joven
10.
J Cell Biochem ; 115(4): 772-84, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24249161

RESUMEN

Current literature provided information that alteration in microRNA expression impacted sensitivity or resistance of certain tumor types to anticancer treatment, including the possible intracellular pathways. The microRNA-23a (miR-23a)-regulated apoptosis in response to the 5-fluorouracil (5-FU)-induced mitochondria-mediated apoptotic pathway was determined in this study. The miR-23a expression in 5-FU-treated and untreated colon cancer cells and tissues was assessed using real-time PCR analysis. To determine the function of miR-23a in the regulation of 5-FU-induced apoptosis, cell-proliferation, cytotoxicity, and apoptosis analyses were performed. Dual luciferase reporter assay was used to identify the apoptosis-related target gene for miR-23a. The activity of caspases-3, -7, and -9 were also assessed in miR-23a antisense and 5-FU treated tumor cells. A xenograft tumor model was established to evaluate the biological relevance of altered miR-23a expression to the 5-FU-based chemotherapy in vivo. We found that the expression of miR-23a was increased and the level of apoptosis-activating factor-1 (APAF-1) was decreased in 5-FU-treated colon cancer cells compared to untreated cells. The activation of the caspases-3 and 7 was increased in miR-23a antisense and 5-FU-treated colon cancer cells compared to negative control. APAF-1, as a target gene of miR-23a, was identified and miR-23a antisense-induced increase in the activation of caspase-9 was observed. The overexpression of miR-23a antisense up-regulated the 5-FU induced apoptosis in colon cancer cells. However, the miR-23a knockdown did not increase the antitumor effect of 5-FU in xenograft model of colon cancer. This study shows that miR-23a antisense enhanced 5-FU-induced apoptosis in colorectal cancer cells through the APAF-1/caspase-9 apoptotic pathway.


Asunto(s)
Apoptosis/genética , Factor Apoptótico 1 Activador de Proteasas/metabolismo , Caspasa 9/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Fluorouracilo/farmacología , MicroARNs/genética , Oligonucleótidos Antisentido/genética , Anciano , Animales , Antimetabolitos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Factor Apoptótico 1 Activador de Proteasas/genética , Secuencia de Bases , Caspasa 9/genética , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Femenino , Fluorouracilo/uso terapéutico , Regulación Neoplásica de la Expresión Génica , Células HCT116/efectos de los fármacos , Células HT29/efectos de los fármacos , Humanos , Masculino , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Yi Chuan ; 35(4): 433-40, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23659933

RESUMEN

As an important sub-field in the study of animal cloning, fish nuclear transfer was first established in the early 1960s by Chinese embryologists. Due to its advantages, zebrafish has become a unique animal model to study the mystery of reprogramming in nuclear transfer. This article summarizes the history and current situation in fish nuclear transfer technology and discusses the factors that may influence the development of the cloned embryos. A comprehensive understand-ing of the mechanism for epigenetic modification following nuclear transfer, such as genomic DNA methylation and histone acetylation and/or methylation, will likely increase the success rate and eventually lead to the future freedom of cloning technique.


Asunto(s)
Reprogramación Celular , Técnicas de Transferencia Nuclear , Pez Cebra/genética , Animales , Embrión no Mamífero/embriología , Embrión no Mamífero/metabolismo , Pez Cebra/embriología
12.
Comb Chem High Throughput Screen ; 16(1): 78-82, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23190576

RESUMEN

In order to find new herbicidally active compounds, a fifteen-member library, focusing on the variation of 3- position substituents of 2,4,5-imidazolidine-trione or 2-thioxo-4,5-imidazolidinedione, was designed and prepared in parallel by the reaction of various ureas or thioureas with oxalyl chloride using solution-phase technology. An interesting and, to the best of our knowledge, unprecedented finding is that a by-product of 1-phenyl-3-propylcarbodiimide was formed during the addition of oxalyl chloride into the solution of 1-phenyl-3-propylthiourea in the presence of triethylamine in dichloromethane. It has been shown that the herbicidal activity of 2,4,5-imidazolidinetriones is about the same as that of their analogous 2-thioxo-4,5-imidazolidinediones. Compound with propyl or isopropyl group at the 3- position of 2,4,5-imidazolidinetrione ring demonstrated good herbicidal activity. The most active compound, 1-(2-fluoro- 4-chloro-5-propargyloxy)-phenyl-3-propyl-2-thioxo-4,5-imidazolidinedione, gave 95% control of the growth of velvetleaf at 200 g/ha in the post-emergence test.


Asunto(s)
Herbicidas/síntesis química , Imidazolidinas/síntesis química , Cloruros/síntesis química , Cloruros/química , Técnicas Químicas Combinatorias/métodos , Herbicidas/química , Imidazolidinas/química , Oxalatos/síntesis química , Oxalatos/química , Tiourea/síntesis química , Tiourea/química
13.
Dig Liver Dis ; 45(1): 38-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23017645

RESUMEN

BACKGROUND: Recent data suggest that the serine protease inhibitor Kazal type 1 (SPINK1) gene mutation is associated with idiopathic chronic pancreatitis. However, few studies have focused on the serine protease inhibitor Kazal type 1 c.194+2T>C mutation. Therefore, our goal was to study the prevalence and impact of serine protease inhibitor Kazal type 1 mutations on the clinical profile of idiopathic chronic pancreatitis patients in China. METHODS: A retrospective-cohort study of 118 Chinese patients with idiopathic chronic pancreatitis was performed, and genetic tests were carried out to detect SPINK1 mutations. Subjects without pancreatitis were used as controls. In total, 118 idiopathic chronic pancreatitis patients and 100 control subjects were evaluated. RESULTS: The serine protease inhibitor Kazal type 1 c.194+2T>C variant was present in 44.9% of patients with idiopathic chronic pancreatitis. The frequency of diabetes in idiopathic chronic pancreatitis patients with the serine protease inhibitor Kazal type 1 c.194+2T>C mutation (39.6%) was higher than that of patients without the mutation (9.2%). The time to occurrence of diabetes mellitus after idiopathic chronic pancreatitis symptom onset is significantly influenced by the c.194+2T>C mutation (p<0.001). In addition, the mean age of diabetes onset in patients with the serine protease inhibitor Kazal type 1 c.194+2T>C mutation (38.33 ± 9.50) was significantly younger than that of patients without this mutation (49.67 ± 6.74). CONCLUSIONS: The presence of the serine protease inhibitor Kazal type 1 c.194+2T>C mutation seems to be associated with idiopathic chronic pancreatitis and could predispose individuals to pancreatic diabetes onset at an earlier age.


Asunto(s)
Pueblo Asiatico/genética , Proteínas Portadoras/genética , Diabetes Mellitus/genética , Pancreatitis Crónica/genética , Adulto , Factores de Edad , Estudios de Casos y Controles , Estudios de Cohortes , Cartilla de ADN/química , Diabetes Mellitus/etiología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Pancreatitis Crónica/complicaciones , Prevalencia , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Inhibidor de Tripsina Pancreática de Kazal
14.
J Cell Mol Med ; 16(2): 249-59, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21388517

RESUMEN

Pre-eclampsia is a leading cause of maternal and foetal morbidity and mortality worldwide. Insufficient uteroplacental oxygenation is believed to be responsible for the disease. However, what molecular events involve in hypoxic responses and how they affect placental development remain unclear. Recently, miRNAs have emerged as a new class of molecules in response to hypoxia. We show here that the expression of microRNA-210 (mir-210) is up-regulated in patients with pre-eclampsia, as well as in trophoblast cells cultured under hypoxic conditions. Ectopic expression of mir-210 inhibited the migration and invasion capability of trophoblast cells. Ephrin-A3 and Homeobox-A9, which related with cell migration and vascular remodelling, were then experimentally validated as the functional targets of mir-210 both in vivo and in vitro. Using luciferase reporter, chromatin immunoprecipitation (ChIP) and small interfering RNA (siRNA) experiments, we finally identified a new transcriptional mechanism that the overexpression of mir-210 under hypoxia was regulated by NF-κB transcriptional factor p50, apart from the well-known HIF 1α. Taken together, our study implicates an important role for mir-210 in the molecular mechanism of pre-eclampsia.


Asunto(s)
MicroARNs/metabolismo , Preeclampsia/metabolismo , Trofoblastos/metabolismo , Estudios de Casos y Controles , Línea Celular Tumoral , Movimiento Celular , Efrina-A3/metabolismo , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , Subunidad p50 de NF-kappa B/genética , Subunidad p50 de NF-kappa B/metabolismo , Preeclampsia/genética , Embarazo , Complicaciones del Embarazo/genética , Interferencia de ARN , ARN Interferente Pequeño
15.
EMBO J ; 28(18): 2719-32, 2009 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-19696742

RESUMEN

We here report that miR-17-92 cluster is a novel target for p53-mediated transcriptional repression under hypoxia. We found the expression levels of miR-17-92 cluster were reduced in hypoxia-treated cells containing wild-type p53, but were unchanged in hypoxia-treated p53-deficient cells. The repression of miR-17-92 cluster under hypoxia is independent of c-Myc. Luciferase reporter assays mapped the region responding to p53-mediated repression to a p53-binding site in the proximal region of the miR-17-92 promoter. Chromatin immunoprecipitation (ChIP), Re-ChIP and gel retardation assays revealed that the binding sites for p53- and the TATA-binding protein (TBP) overlap within the miR-17-92 promoter; these proteins were found to compete for binding. Finally, we show that pri-miR-17-92 expression correlated well with p53 status in colorectal carcinomas. Over-express miR-17-92 cluster markedly inhibits hypoxia-induced apoptosis, whereas blocked miR-17-5p and miR-20a sensitize the cells to hypoxia-induced apoptosis. These data indicated that p53-mediated repression of miR-17-92 expression likely has an important function in hypoxia-induced apoptosis, and thus further our understanding of the tumour suppressive function of p53.


Asunto(s)
Apoptosis , MicroARNs/genética , Familia de Multigenes , Proteína p53 Supresora de Tumor/genética , Sitios de Unión , Células CACO-2 , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Humanos , Hipoxia , Cinética , Luciferasas/metabolismo , Modelos Biológicos , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
16.
J Clin Gastroenterol ; 43(9): 831-7, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19461527

RESUMEN

GOALS: To gain an insight into the putative role of annexin A5 (ANXA5) in the tumor stage and its clinical outcome. BACKGROUND: ANXA5 is a calcium-binding protein, which has been implicated in the carcinogenesis of several carcinomas. However, the role of ANXA5 in colorectal cancer (CRC) is unclear. STUDY: We investigated the expression of ANXA5 in colorectal adenocarcinoma. This study included 207 consecutive patients with sporadic CRC. Paired colorectal tissue samples and corresponding nonmalignant tissues were obtained by surgical resection. ANXA5 mRNA and protein expression in each tissue were assessed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical staining. Data were statistically correlated with pathologic parameters and clinical outcome. RESULTS: Real-time reverse transcriptase polymerase chain reaction showed that there is an up-regulation in the mRNA level of ANXA5 in tumors (P<0.001). Immunohistochemical study revealed that high ANXA5 expression was present in 40.58% (84 of 207) of tumors. Univariate analysis showed increased ANXA5 expression correlated with pT stage (P=0.008), liver metastasis (P=0.024), pathologic tumor-node-metastasis stage (P=0.015), Dukes' stage (P=0.017), recurrence (P=0.024), cancer-related death (P=0.028), recurrence-free probability (P=0.003), and overall survival (P=0.005). Multivariate analysis showed that ANXA5 expression and liver metastasis significantly correlated with recurrence-free probability (P=0.039 and P=0.048, respectively) and overall survival (P=0.012 and P=0.021, respectively) independent of pT stage and pN stage. CONCLUSIONS: From these findings ANXA5 expression seems to be related to the tumor stage and clinical outcome of CRC. Thus ANXA5 could serve as a prognostic marker for tumor progression.


Asunto(s)
Adenocarcinoma/química , Anexina A5/análisis , Biomarcadores de Tumor/análisis , Neoplasias Colorrectales/química , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Anciano , Anexina A5/genética , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Neoplasias Hepáticas/química , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Regulación hacia Arriba
17.
Int J Biochem Cell Biol ; 40(10): 2151-63, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18378486

RESUMEN

Annexins are a family of calcium-dependent phospholipid-binding proteins that have been proposed to be involved in a wide range of important biological processes. At present, only a few annexins have been identified in parasites, and the physiological roles of these annexins are obscure. Earlier, we cloned a novel annexin (annexin B1) from Taenia solium metacestodes and found that annexin B1 was detectable in the surrounding host-derived layer with granulomaous infiltration. The objective of this study was to investigate the secretion and physiological function of annexin B1. We expressed a green fluorescent protein-tagged annexin B1 (GFP-anxB1) in living SiHa cells and showed that it was secreted upon stimulation with dexamethasone (Dex). This secretion was not inhibited by brefeldin A but was blocked by pre-treatment with the intracellular calcium-specific chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Furthermore, we describe for the first time that annexin B1 can bind to the extracellular surface of human eosinophils and produce Ca(2+)-influx. The Ca(2+)-influx induced apoptosis in eosinophils, which was inhibited by pre-loading the Ca(2+) channel blocker 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-metho-xyphenethyl]-1H-imidazole, HCl (SKF-96365). In conclusion, these findings represent direct and substantial evidence for the secretion of annexin B1 by living cells; the apoptosis in eosinophil induced by annexin B1 might be a novel strategy for T. solium metacestodes to prevent the host's immune attack.


Asunto(s)
Anexinas/farmacología , Apoptosis/efectos de los fármacos , Calcio/farmacología , Eosinófilos/citología , Eosinófilos/efectos de los fármacos , Inmunidad/efectos de los fármacos , Taenia solium/metabolismo , Animales , Brefeldino A/farmacología , Calcimicina/farmacología , Señalización del Calcio/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Citocromos c/metabolismo , Dexametasona/farmacología , Eosinófilos/enzimología , Exocitosis/efectos de los fármacos , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Modelos Biológicos , Unión Proteica/efectos de los fármacos , Proteínas Recombinantes de Fusión/metabolismo
18.
Cancer Sci ; 99(4): 770-80, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18307539

RESUMEN

China has the largest numbers of hereditary non-polyposis colorectal cancer (HNPCC) patients based on its population of 1.4 billion. However, the clinical data and mismatch repair (MMR) gene analyses have been limited. Here we performed microsatellite instability (MSI) and immunohistochemistry (IHC) analyses on a series of patients with a high-risk for HNPCC: 61 patients with family histories fulfilling Amsterdam criteria II (ACII-HNPCC) or suspected HNPCC criteria (S-HNPCC), and 106 early onset colorectal cancer (CRC) patients. Sixty late-onset CRC patients were used as control. Methylation of the hMLH1 promoter was analyzed on tumors lacking hMLH1 expression. MMR germ-line mutations were screened on patients with tumors classified as MSI-H/L or negative for IHC. We identified 27 germ-line MMR variants in the 167 patients with a high-risk for HNPCC while only one germ-line mutation in hMSH6 was found in the late-onset CRC group. Of those, 23 were pathogenic mutations. The high incidence of gastric and hepatobiliary cancers coupled with the increasing number of small families in China reduces the sensitivity (43.5%, 30.4%) and positive predictive value (PPV) (45.5%, 17.9%) of the ACII- or S-HNPCC criteria. MSI or IHC testing are highly sensitive in detecting pathogenic mutations (sensitivities = 91.3% and 95.6%, respectively), but the PPVs are quite low (25.6% and 27.8%, respectively). Considering that all 12 tumors with pathogenic mutations in hMLH1 also showed promoter unmethylation, the sensitivity of IHC in conjunction with hMLH1 promoter methylation analysis is not reduced, but the PPV was increased from 27.8% to 61.1%, and the total cost was greatly reduced.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Pueblo Asiatico/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Reparación de la Incompatibilidad de ADN , Pruebas Genéticas/métodos , Proteínas Nucleares/genética , Adulto , China , Análisis Costo-Beneficio , Metilación de ADN , Proteínas de Unión al ADN/genética , Femenino , Pruebas Genéticas/economía , Mutación de Línea Germinal , Humanos , Inmunohistoquímica , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS/genética , Regiones Promotoras Genéticas
19.
Cell Biol Int ; 32(1): 121-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17936648

RESUMEN

Annexin B1 is a novel member of the annexin superfamily which was isolated from a Cysticercus cellulosae cDNA library. To investigate the physiological roles of annexin B1, we firstly performed immunohistochemical analysis on frozen Cysticercus cellulosae sections and found that annexin B1 was present not only in the tegument of the bladder wall, but also in the host-derived inflammatory layer; In addition, ELISA analysis revealed that annexin B1 could be detected in the cystic fluid of Cysticercus cellulosae and the sera of pigs with cysticercosis. These findings indicated that annexin B1 might be a secretary protein. We further constructed a pEGFP-annexin B1 plasmid and transfected it into SiHa cells. We found that GFP-annexin B1 was stimulated to translocate to the plasma membrane by phorbol 12-myristate 13-acetate (PMA). By contrast, it was induced to distribute at the plasma and nuclear membranes by treatment with calcium ionophore ionomycin. PMA increased annexin B1 membrane binding, which might facilitate exocytosis. Moreover, translocation of the protein to the plasma and nuclear membranes after stimulated by ionomycin, was predicted to be related to an additional function.


Asunto(s)
Anexinas/metabolismo , Proteínas del Helminto/metabolismo , Ionomicina/farmacología , Ésteres del Forbol/farmacología , Animales , Calcio/metabolismo , Cisticercosis/metabolismo , Citosol/efectos de los fármacos , Citosol/metabolismo , Femenino , Humanos , Inmunohistoquímica , Porcinos , Taenia solium/metabolismo , Células Tumorales Cultivadas , Neoplasias del Cuello Uterino/metabolismo
20.
Appl Microbiol Biotechnol ; 77(2): 483-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17768617

RESUMEN

To develop faster, less expensive methods for expression and purification of proteins, the annexin B1-intein fusion expression system was constructed. The interest proteins fused to the annexin B1-intein tag were purified in a single-step method based on the Ca(2+)-binding activity of annexin B1, and the annexin B1-intein fusion tag was removed based on the self-cleaving activity of the intein. Moreover, we found that in some cases, fusion to annexin B1 can promote the solubility of heterologous proteins. The production of soluble and highly active of interleukin-2 and low-molecular single-chain urokinase in our results proved that the system was a novel, cheap and effective fusion expression system for the production of valuable soluble recombinant proteins in Escherichia coli.


Asunto(s)
Anexinas/metabolismo , Biotecnología/métodos , Proteínas del Helminto/metabolismo , Interleucina-2/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Animales , Anexinas/genética , Biotecnología/economía , Calcio/química , Precipitación Química , Cysticercus/metabolismo , Escherichia coli , Proteínas del Helminto/genética , Humanos , Inteínas/genética , Inteínas/fisiología , Interleucina-2/genética , Ratones , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/economía , Proteínas Recombinantes de Fusión/genética , Activador de Plasminógeno de Tipo Uroquinasa/genética
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