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1.
Medicina (Kaunas) ; 59(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36676703

RESUMEN

Arboviruses have been reported over the years as constant threats to blood transfusion recipients, given the high occurrence of asymptomatic cases and the fact that the presence of viremia precedes the onset of symptoms, making it possible that infected blood from donors act as a source of dissemination. This work aims to identify the prevalence of dengue virus (DENV), Zika virus (ZIKV) and Chikungunya virus (CHIKV) infection in blood donors during epidemic and non-epidemic periods; classify the donor as symptomatic or asymptomatic; and verify the need to include DENV, CHIKV and ZIKV in the nucleic acid test (NAT) platform in northern Brazil. We investigated 36,133 thousand donations in two years of collection in Northern Brazil. One donor was positive for DENV and one for CHIKV (0.002% prevalence). As the prevalence for arboviruses was low in this study, it would not justify the individual screening of samples from donors in a blood bank. Thus, DENV- and CHIKV-positive samples were simulated in different amounts of sample pools, and both were safely detected by molecular biology even in a pool of 14 samples, which would meet the need to include these three viruses in the routine of blood centers in endemic countries such as Brazil.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Humanos , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/diagnóstico , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/diagnóstico , Dengue/epidemiología , Dengue/diagnóstico , Donantes de Sangre , Brasil/epidemiología , Prevalencia
2.
Pathobiology ; 88(2): 156-169, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33588422

RESUMEN

Identifying a microbiome pattern in gastric cancer (GC) is hugely debatable due to the variation resulting from the diversity of the studied populations, clinical scenarios, and metagenomic approach. H. pylori remains the main microorganism impacting gastric carcinogenesis and seems necessary for the initial steps of the process. Nevertheless, an additional non-H. pylori microbiome pattern is also described, mainly at the final steps of the carcinogenesis. Unfortunately, most of the presented results are not reproducible, and there are no consensual candidates to share the H. pylori protagonists. Limitations to reach a consistent interpretation of metagenomic data include contamination along every step of the process, which might cause relevant misinterpretations. In addition, the functional consequences of an altered microbiome might be addressed. Aiming to minimize methodological bias and limitations due to small sample size and the lack of standardization of bioinformatics assessment and interpretation, we carried out a comprehensive analysis of the publicly available metagenomic data from various conditions relevant to gastric carcinogenesis. Mainly, instead of just analyzing the results of each available publication, a new approach was launched, allowing the comprehensive analysis of the total sample amount, aiming to produce a reliable interpretation due to using a significant number of samples, from different origins, in a standard protocol. Among the main results, Helicobacter and Prevotella figured in the "top 6" genera of every group. Helicobacter was the first one in chronic gastritis (CG), gastric cancer (GC), and adjacent (ADJ) groups, while Prevotella was the leader among healthy control (HC) samples. Groups of bacteria are differently abundant in each clinical situation, and bacterial metabolic pathways also diverge along the carcinogenesis cascade. This information may support future microbiome interventions aiming to face the carcinogenesis process and/or reduce GC risk.


Asunto(s)
Microbioma Gastrointestinal/genética , Neoplasias Gástricas/microbiología , Biología Computacional , Mucosa Gástrica/microbiología , Microbioma Gastrointestinal/fisiología , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , Humanos , Redes y Vías Metabólicas , Metagenoma , Prevotella/genética , Prevotella/patogenicidad
3.
Int J Mol Sci ; 21(5)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32150871

RESUMEN

Despite the advancements in cancer treatments, gastric cancer is still one of the leading causes of death worldwide. In this context, it is of great interest to discover new and more effective ways of treating this disease. Accumulated evidences have demonstrated the amplification of 8q24.21 region in gastric tumors. Furthermore, this is the region where the widely known MYC oncogene and different microRNAs are located. MYC deregulation is key in tumorigenesis in various types of tissues, once it is associated with cell proliferation, survival, and drug resistance. microRNAs are a class of noncoding RNAs that negatively regulate the protein translation, and which deregulation is related with gastric cancer development. However, little is understood about the interactions between microRNAs and MYC. Here, we overview the MYC role and its relationship with the microRNAs network in gastric cancer aiming to identify potential targets useful to be used in clinic, not only as biomarkers, but also as molecules for development of promising therapies.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Neoplasias Gástricas/patología , Animales , Humanos , Proteínas Proto-Oncogénicas c-myc/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
4.
J Cell Biochem ; 118(4): 869-877, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27748538

RESUMEN

Different from genetic alterations, the reversible nature of epigenetic modifications provides an interesting opportunity for the development of clinically relevant therapeutics in different tumors. In this study, we aimed to screen and validate candidate genes regulated by the epigenetic marker associated with transcriptional activation, histone acetylation, in gastric cancer (GC). We first compared gene expression profile of trichostatin A-treated and control GC cell lines using microarray assay. Among the 55 differentially expressed genes identified in this analysis, we chose the up-regulated genes BMP8B and BAMBI for further analyses, that included mRNA and histone acetylation quantification in paired GC and nontumor tissue samples. BMP8B expression was reduced in GC compared to nontumor samples (P < 0.01). In addition, reduced BMP8B expression was associated with poorly differentiated GC (P = 0.02). No differences or histopathological associations were identified concerning BAMBI expression. Furthermore, acetylated H3K9 and H4K16 levels at BMP8B were increased in GC compared to nontumors (P < 0.05). However, reduced levels of acetylated H3K9 and H4K16 were associated with poorly differentiated GC (P < 0.05). Reduced levels of acetylated H3K9 was also associated with diffuse-type histological GC (P < 0.05). Notably, reduced BMP8B mRNA and acetylated H4K16 levels were positively correlated in poorly differentiated GC (P < 0.05). Our study demonstrated that BMP8B seems to be a tumor suppressor gene regulated by H4K16 acetylation in poorly differentiated GC. Therefore, BMP8B may be a potential target for TSA-based therapies in this GC sample subset. J. Cell. Biochem. 118: 869-877, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Proteínas Morfogenéticas Óseas/genética , Genes Supresores de Tumor , Histonas/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Acetilación , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Diferenciación Celular/genética , Línea Celular Tumoral , Epigénesis Genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ácidos Hidroxámicos/farmacología , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Neoplasias Gástricas/tratamiento farmacológico
5.
Exp Mol Pathol ; 103(1): 101-111, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28736214

RESUMEN

Cancer is a multifactorial disease that involves many molecular alterations. Gastric cancer (GC) is the third leading cause of cancer death worldwide. GC is a highly heterogeneous disease with different molecular and genetics features. Therefore, this review focuses on an overview of the genetic aspects of gastric cancer by highlighting the important impact and role of deletions and/or duplications of chromosomal segments, genomic variants, H. pylori infection and interleukin variants, as found in gene expression and newly proposed molecular classification studies. The challenge is to better understand the mechanisms and different pathways that lead to the development and progression of GC.


Asunto(s)
Polimorfismo Genético , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Variaciones en el Número de Copia de ADN , Estudio de Asociación del Genoma Completo , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Humanos , Interleucinas/genética , Interleucinas/metabolismo , Metaanálisis como Asunto , Transducción de Señal , Neoplasias Gástricas/etiología
6.
Tumour Biol ; 37(8): 9991-10010, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27126070

RESUMEN

Gastric cancer is a complex, heterogeneous, and multistep disease. Over the past decades, several studies have aimed to determine the molecular factors that lead to gastric cancer development and progression. After completing the human genome sequencing, proteomic technologies have presented rapid progress. Differently from the relative static state of genome, the cell proteome is dynamic and changes in pathologic conditions. Proteomic approaches have been used to determine proteome profiles and identify differentially expressed proteins between groups of samples, such as neoplastic and nonneoplastic samples or between samples of different cancer subtypes or stages. Therefore, proteomic technologies are a useful tool toward improving the knowledge of gastric cancer molecular pathogenesis and the understanding of tumor heterogeneity. This review aimed to summarize the proteins or protein families that are frequently identified by using high-throughput screening methods and which thus may have a key role in gastric carcinogenesis. The increased knowledge of gastric carcinogenesis will clearly help in the development of new anticancer treatments. Although the studies are still in their infancy, the reviewed proteins may be useful for gastric cancer diagnosis, prognosis, and patient management.


Asunto(s)
Transformación Celular Neoplásica , Proteínas de Neoplasias/análisis , Proteómica/métodos , Neoplasias Gástricas/etiología , Ensayos Analíticos de Alto Rendimiento , Humanos , Proteínas de Neoplasias/clasificación , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiología , Procesamiento Proteico-Postraduccional , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Electroforesis Bidimensional Diferencial en Gel
7.
Ecotoxicol Environ Saf ; 132: 111-5, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27290641

RESUMEN

Maintaining water quality within tolerable limits is a basic need of the riverside communities in the Amazon. Using endemic aquatic organisms as biological models is useful for monitoring the environment. In this study, potential cytotoxic and genotoxic damages in Plagioscion squamosissimus (commonly known as silver croaker) from the Marajó Archipelago were evaluated using a flow cytometry assay and a survey of micronuclei (MN) frequency as well as other nuclear abnormalities (NA). P. squamosissimus specimens were collected at four locations in the Marajó Archipelago. Blood samples from these fish were used in the flow cytometry assay and piscine micronucleus test, and the resulting data were analyzed using analysis of variance (ANOVA). We did not observe a difference in the erythrocyte cell cycle distribution among the samples (P=0.9992), which suggests the absence of cytotoxic agent-induced apoptosis. The piscine micronucleus test exhibited differences in the samples from São Sebastião da Boa Vista (SSBV), and those from Anajás produced the highest mutagenicity indices. The MN frequencies were low for all groups, but the groups exhibited significantly different frequencies (P=0.0033). Reniform nuclei, nuclei with extensions, and lobed nuclei were combined and considered NA. The frequency differences for these NA were significant among sampling sites (P <0.0001). This report is the first to use flow cytometry in fish to evaluate cytotoxic agent-induced apoptosis. The micronucleus test results indicate the presence of pollutants that can change the genetic material of the fish studied. We also demonstrate that the Amazonian fish P. squamosissimus is important not only as a comestible species but also as an adequate model for biomonitoring in aquatic environments.


Asunto(s)
Citotoxinas/toxicidad , Mutágenos/toxicidad , Perciformes , Contaminantes del Agua/toxicidad , Animales , Apoptosis/efectos de los fármacos , Brasil , Ciclo Celular/efectos de los fármacos , Daño del ADN , Monitoreo del Ambiente , Eritrocitos/efectos de los fármacos , Pruebas de Micronúcleos , Perciformes/genética , Ríos
8.
Homeopathy ; 105(3): 265-269, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27473548

RESUMEN

BACKGROUND: CANOVA(®) (CA) is a homeopathic immunomodulator. It contains several homeopathic medicines prepares according to the Brazilian Pharmacopoeia. CA is indicated in clinical conditions in which the immune system is impaired and against tumors. N-methyl-N-nitrosourea (NMU) is an N-nitroso compound, with genotoxic/mutagenic properties. Although several studies have shown promising results in the use of CA, there are no studies reporting possible antigenotoxic effects. METHOD: This study evaluated the in vitro antigenotoxic and anticytotoxic effects of CA in human lymphocytes exposed to NMU. Samples of human lymphocytes that were subjected to different concentrations of a mixture containing CA and NMU were used. The genotoxicity/antigenotoxicity of CA was evaluated by the comet assay, anticytotoxicity was assessed by quantification of apoptosis and necrosis using acridine orange/ethidium bromide. RESULTS: CA significantly reduced DNA damage induced by NMU and reduced significantly the frequency of NMU-induced apoptosis after 24 h of treatment. CONCLUSION: CA has an important cytoprotective effect significantly reducing the DNA damage and apoptosis induced by the carcinogen NMU.


Asunto(s)
Venenos de Crotálidos/farmacología , Citoprotección , Daño del ADN/efectos de los fármacos , Homeopatía , Linfocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Adulto , Apoptosis , Células Cultivadas , Femenino , Humanos , Masculino , Metilnitrosourea/efectos adversos , Pruebas de Mutagenicidad
9.
Tumour Biol ; 35(2): 1107-11, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24014049

RESUMEN

To verify the methylation status of THBS1, GPX3, and COX2 genes and to evaluate their association with Helicobacter pylori in gastric adenocarcinomas. Methylation-sensitive restriction enzyme PCR assay was performed in 16 diffuse type gastric cancer samples, 23 intestinal type, and 15 normal stomach tissue. The presence of H. pylori was performed by amplification of the fragment of the 16S rRNA. Statistical analyses were performed using Fisher's exact test. The hypermethylation of GPX3, THBS1, and COX2 occurred in 18 (n = 7), 5 (n = 2), and 36 % (n = 14) of gastric cancer samples, respectively, whereas in normal samples, it was found in 13, 7, and 67 %. The presence of H. pylori was detected in 67 % of gastric cancer samples and 67 % in normal gastric samples. The methylation of THBS1 and GPX3 was not significantly different between the types of tumors, normal sample, the presence of H. pylori, or clinicopathological variables studied (P > 0.05). However, the methylation status of the gene COX2 is significantly different between normal tissue and intestinal type gastric cancer (P = 0.02). Therefore, our results suggest that the methylation status of the gene COX2 is associated with the intestinal type of gastric cancer.


Asunto(s)
Ciclooxigenasa 2/genética , Glutatión Peroxidasa/genética , Neoplasias Intestinales/genética , Neoplasias Gástricas/genética , Brasil , Islas de CpG/genética , Metilación de ADN/genética , Femenino , Estudios de Asociación Genética , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/patogenicidad , Humanos , Neoplasias Intestinales/microbiología , Neoplasias Intestinales/patología , Masculino , Regiones Promotoras Genéticas , ARN Ribosómico 16S/genética , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología
10.
Tumour Biol ; 35(4): 3447-53, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24338710

RESUMEN

Aberrant methylation has been reported in several neoplasias, including gastric cancer. The methyl-CpG-binding domain (MBD) family proteins have been implicated in the chromatin remodeling process, leading to the modulation of gene expression. To evaluate the role of MBD2 and MBD3 in gastric carcinogenesis and the possible association with clinicopathological characteristics, we assessed the mRNA levels and promoter methylation patterns in gastric tissues. In this study, MBD2 and MBD3 mRNA levels were determined by RT-qPCR in 28 neoplastic and adjacent nonneoplastic and 27 gastritis and non-gastritis samples. The promoter methylation status was determined by bisulfite sequencing, and we found reduced MBD2 and MBD3 levels in the neoplastic samples compared with the other groups. Moreover, a strong correlation between the MBD2 and MBD3 expression levels was observed in each set of paired samples. Our data also showed that the neoplastic tissues exhibited higher MBD2 promoter methylation than the other groups. Interestingly, the non-gastritis group was the only one with positive methylation in the MBD3 promoter region. Furthermore, a weak correlation between gene expression and methylation was observed. Therefore, our data suggest that DNA methylation plays a minor role in the regulation of MBD2 and MBD3 expression, and the presence of methylation at CpGs that interact with transcription factor complexes might also be involved in the modulation of these genes. Moreover, reduced mRNA expression of MBD2 and MBD3 is implicated in gastric carcinogenesis, and thus, further investigations about these genes should be conducted for a better understanding of the role of abnormal methylation involved in this neoplasia.


Asunto(s)
Proteínas de Unión al ADN/genética , ARN Mensajero/análisis , Neoplasias Gástricas/etiología , Adulto , Anciano , Islas de CpG , Metilación de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología
11.
Tumour Biol ; 35(7): 6373-81, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24668547

RESUMEN

Gastric cancer is still the second leading cause of cancer-related death worldwide, even though its incidence and mortality have declined over the recent few decades. Epigenetic control using histone deacetylase inhibitors, such as trichostatin A (TSA), is a promising cancer therapy. This study aimed to assess the messenger RNA (mRNA) levels of three histone deacetylases (HDAC1, HDAC2, and HDAC3), two histone acetyltransferases (GCN5 and PCAF), and two possible targets of these histone modifiers (MYC and CDKN1A) in 50 matched pairs of gastric tumors and corresponding adjacent nontumors samples from patients with gastric adenocarcinoma, as well as their correlations and their possible associations with clinicopathological features. Additionally, we evaluated whether these genes are sensitive to TSA in gastric cancer cell lines. Our results demonstrated downregulation of HDAC1, PCAF, and CDKN1A in gastric tumors compared with adjacent nontumors (P < 0.05). On the other hand, upregulation of HDAC2, GCN5, and MYC was observed in gastric tumors compared with adjacent nontumors (P < 0.05). The mRNA level of MYC was correlated to HDAC3 and GCN5 (P < 0.05), whereas CDKN1A was correlated to HDAC1 and GCN5 (P < 0.05 and P < 0.01, respectively). In addition, the reduced expression of PCAF was associated with intestinal-type gastric cancer (P = 0.03) and TNM stages I/II (P = 0.01). The increased expression of GCN5 was associated with advanced stage gastric cancer (P = 0.02) and tumor invasion (P = 0.03). The gastric cell lines treated with TSA showed different patterns of histone deacetylase and acetyltransferase mRNA expression, downregulation of MYC, and upregulation of CDKN1A. Our findings suggest that alteration of histone modifier genes play an important role in gastric carcinogenesis, contributing to MYC and CDKN1A deregulation. In addition, all genes studied here are modulated by TSA, although this modulation appears to be dependent of the genetic background of the cell line.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inhibidores de Histona Desacetilasas/administración & dosificación , Ácidos Hidroxámicos/administración & dosificación , ARN Mensajero/biosíntesis , Neoplasias Gástricas/enzimología , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/biosíntesis , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica/genética , Genes myc/genética , Histona Desacetilasa 1/biosíntesis , Histona Desacetilasa 1/genética , Histona Desacetilasa 2/biosíntesis , Histona Desacetilasa 2/genética , Histona Desacetilasas/biosíntesis , Histona Desacetilasas/genética , Humanos , ARN Mensajero/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Activación Transcripcional/efectos de los fármacos , Factores de Transcripción p300-CBP/biosíntesis , Factores de Transcripción p300-CBP/genética
12.
BMC Gastroenterol ; 14: 9, 2014 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-24410879

RESUMEN

BACKGROUND: The process of gastric carcinogenesis still remains to be elucidated. The identification of genes related to this process may help to reduce mortality rates through early diagnosis and the development of new anticancer therapies. Nucleophosmin 1 (NPM1) acts in ribosome biogenesis, centrosome duplication, maintenance of genomic stability, and embryonic development. Recently, NPM1 has been implicated in the tumorigenesis processes. Here, we evaluated NPM1 gene and protein expression in gastric tumors and in corresponding non-neoplastic gastric samples. METHODS: NPM1 protein expression was determined by Western blot in 17 pairs of gastric tumors and corresponding non-neoplastic gastric tissue. The protein immunoreactivity was observed in 12 tumor samples. mRNA expression was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in 22 pairs of gastric tumors and in matched non-neoplastic gastric tissue. RESULTS: NPM1 protein expression was significantly reduced in gastric cancer samples compared to matched non-neoplastic gastric samples (P = 0.019). The protein level of NPM1 was reduced at least 1.5-fold in 35% of tumors compared to paired non-neoplastic gastric tissue. However, NPM1 immunoreactivity was detected in neoplastic and non-neoplastic cells, including in intestinal metaplastic, gastritis and inflammatory cells. NPM1 was mainly expressed in nucleus and nucleolus subcellular compartments. The staining intensity and the percentage of immunoreactive cells varied among the studied cases. The NPM1 mRNA level was reduced at least 1.5-fold in 45.5% of samples and increased in 27.3% of samples. An inverse correlation between protein and mRNA expression was detected (r = -0.509, P = 0.037). Intestinal-type gastric cancer presented higher mRNA levels than diffuse-type (P = 0.026). However, reduced NPM1 protein expression was associated with intestinal-type gastric cancer compared to matched non-neoplastic gastric samples (P = 0.018). In addition, tumors from patients with known distant metastasis presented reduced NPM1 protein levels compared to tumors from patients without distant metastasis (P < 0.001). CONCLUSION: Although the expression of NPM1 is heterogeneous in gastric tumors, our results suggest that NPM1 down-regulation may have a role in gastric carcinogenesis and may help in the selection of anticancer treatment strategies.


Asunto(s)
Mucosa Gástrica/patología , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares/genética , ARN Mensajero/metabolismo , Neoplasias Gástricas/genética , Adulto , Nucléolo Celular/química , Núcleo Celular/química , Femenino , Mucosa Gástrica/metabolismo , Gastritis/metabolismo , Humanos , Inmunohistoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Persona de Mediana Edad , Metástasis de la Neoplasia , Proteínas Nucleares/análisis , Proteínas Nucleares/metabolismo , Nucleofosmina , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología
13.
BMC Gastroenterol ; 14: 179, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25318991

RESUMEN

BACKGROUND: Helicobacter pylori (HP) and Epstein-Barr virus (EBV) have been associated with cancer development. We evaluated the prevalence of HP, HP CagA+ and EBV infection in gastric cancer (GC) samples from adults and in gastric tissues from patients who underwent upper endoscopy (UE). METHODS: Samples from UE and GC were collected to investigate the presence of HP infection and the HP virulence factor CagA by a urease test and PCR. The presence of EBV was detected by Eber-1 in situ hybridization. RESULTS: In UE, 85.5% of juvenile patients showed some degree of gastritis (45.3% of patients with mild gastritis and 54.7% with moderate/severe gastritis) and patients with mild gastritis were younger than patients with moderate/severe gastritis. Among adults, 48.7% presented mild gastritis and 51.3% moderate/severe gastritis. HP infection was detected in 0% of normal mucosa, 58.5% of juvenile gastritis patients, 69.2% of adult gastritis patients and 88% of GC patients. In these same groups, HP CagA+ was detected in 0%, 37.7%, 61.5% and 67.2% of tissue samples, respectively. In juvenile patients, HP infection was more common in those with gastritis than in normal samples (p = 0.004). The patients with either HP or HP CagA+ were older than patients without these pathogens (p < 0.05). In juvenile patients, HP infection was more frequent in cases of moderate/severe gastritis than in cases of mild gastritis (p = 0.026). Moreover, in patients with GC, HP infection was more frequent in males than in females (p = 0.023). GC patients with HP CagA+ were older than patients with HP CagA- (p = 0.027). HP CagA+ was more common in intestinal-type than diffuse-type GC (p = 0.012). HP CagA+ was also associated with lymph-node (p = 0.024) and distal (p = 0.005) metastasis. No association between EBV infection and HP infection or any clinicopathological variable was detected. CONCLUSIONS: Our results suggest that HP is involved in the pathophysiology of severe gastric lesions and in the development of GC, particularly when CagA+ is present. EBV was not the primary pathogenic factor in our samples.


Asunto(s)
Infecciones por Virus de Epstein-Barr/diagnóstico , Gastritis/diagnóstico , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Neoplasias Gástricas/microbiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antígenos Bacterianos/análisis , Proteínas Bacterianas/análisis , Niño , Preescolar , Infecciones por Virus de Epstein-Barr/patología , Gastritis/patología , Gastroscopía , Infecciones por Helicobacter/patología , Helicobacter pylori/aislamiento & purificación , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Lactante , Persona de Mediana Edad , Estómago/química , Estómago/microbiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/virología , Adulto Joven
14.
Hered Cancer Clin Pract ; 12(1): 18, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25180051

RESUMEN

BACKGROUND: Hereditary diffuse gastric cancer (HDGC) is a hereditary autosomal inherited syndrome associated with CDH1 germline mutations. In Brazil, gastrointestinal tumors are among the most prevalent tumor types and constitute a serious public health problem, especially in the northern and northeastern regions. This study aimed to investigate germline mutations, methylation pattern and genomic rearrangements in the CDH1 gene and quantitative changes in the DNA of HDGC patients in northern and northeastern Brazil. METHODS: Twenty-seven DNA samples from the members of four families affected by HDGC were analyzed using array comparative genomic hybridization (aCGH), DNA sequencing and methylation pattern. RESULTS: No evidence of gain and loss events or any rearrangements were found in any of the samples tested using aCGH. No promoter region hypermethylation was observed either. Two of the four families presented different types of germline mutations. The 185G > T and 1018A > G germline mutations detected in this study have been described in Asian and European families, respectively. The ancestors of the two families carrying these mutations had originated from those continents. CONCLUSION: This is the first study to evaluate CDH1 gene germline mutations in Brazilian families with HDGC. In our study, 50% of the families showed no CDH1 gene alterations, and it is possible that in regions with a high incidence of gastric cancer, such as northern and northeastern Brazil, environmental factors might have induced the different genetic alterations analyzed in this study.

15.
BMC Gastroenterol ; 13: 141, 2013 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-24053468

RESUMEN

BACKGROUND: MYC deregulation is a common event in gastric carcinogenesis, usually as a consequence of gene amplification, chromosomal translocations, or posttranslational mechanisms. FBXW7 is a p53-controlled tumor-suppressor that plays a role in the regulation of cell cycle exit and reentry via MYC degradation. METHODS: We evaluated MYC, FBXW7, and TP53 copy number, mRNA levels, and protein expression in gastric cancer and paired non-neoplastic specimens from 33 patients and also in gastric adenocarcinoma cell lines. We also determined the invasion potential of the gastric cancer cell lines. RESULTS: MYC amplification was observed in 51.5% of gastric tumor samples. Deletion of one copy of FBXW7 and TP53 was observed in 45.5% and 21.2% of gastric tumors, respectively. MYC mRNA expression was significantly higher in tumors than in non-neoplastic samples. FBXW7 and TP53 mRNA expression was markedly lower in tumors than in paired non-neoplastic specimens. Moreover, deregulated MYC and FBXW7 mRNA expression was associated with the presence of lymph node metastasis and tumor stage III-IV. Additionally, MYC immunostaining was more frequently observed in intestinal-type than diffuse-type gastric cancers and was associated with MYC mRNA expression. In vitro studies showed that increased MYC and reduced FBXW7 expression is associated with a more invasive phenotype in gastric cancer cell lines. This result encouraged us to investigate the activity of the gelatinases MMP-2 and MMP-9 in both cell lines. Both gelatinases are synthesized predominantly by stromal cells rather than cancer cells, and it has been proposed that both contribute to cancer progression. We observed a significant increase in MMP-9 activity in ACP02 compared with ACP03 cells. These results confirmed that ACP02 cells have greater invasion capability than ACP03 cells. CONCLUSION: In conclusion, FBXW7 and MYC mRNA may play a role in aggressive biologic behavior of gastric cancer cells and may be a useful indicator of poor prognosis. Furthermore, MYC is a candidate target for new therapies against gastric cancer.


Asunto(s)
Adenocarcinoma/genética , Proteínas de Ciclo Celular/genética , Variaciones en el Número de Copia de ADN , Proteínas F-Box/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-myc/genética , Neoplasias Gástricas/genética , Proteína p53 Supresora de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Adulto , Anciano , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proteínas F-Box/metabolismo , Proteína 7 que Contiene Repeticiones F-Box-WD , Femenino , Perfilación de la Expresión Génica , Humanos , Metástasis Linfática/genética , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-myc/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirugía , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
17.
J Appl Toxicol ; 33(2): 151-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21953315

RESUMEN

Artemisinin is a sesquiterpene lactone endoperoxide, obtained from Artemisia annua, and extensively used as an antimalarial drug. Many studies have reported the genotoxic and cytotoxic effects of artemisinins; however, there are no studies that compare such effects between cancer cell lines and normal human cells after treatment with artemether, an artemisinin derivative. Gastric cancer is the fourth most frequent type of cancer and the second highest cause of cancer mortality worldwide. Thus, the aim of this study was to evaluate the in vitro genotoxic and cytotoxic effects induced by artemether in gastric cancer cell line (PG100) and compare them with the results obtained in human lymphocytes exposed to the same conditions. We used MTT (3-(4,5-methylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide) assay, comet assay and ethidium bromide/acridine orange viability staining to evaluate the cytotoxic and genotoxic effects of artemether in PG100. MTT assay showed a decrease in the survival percentages for both cell types treated with different concentrations of artemether (P < 0.05). PG100 also showed a significant dose-dependent increase in DNA damage index at concentrations of 119.4 and 238.8 µg ml(-1) (P < 0.05). Our results showed that artemether induced necrosis in PG100 at concentrations of 238.8 and 477.6 µg ml(-1), for all the tested harvest times (P < 0.05). In lymphocytes, artemether induced both apoptosis and necrosis at concentrations of 238.8 and 477.6 µg ml(-1), for all the tested harvest times (P < 0.05). In conclusion, human lymphocytes were more sensitive to the cytotoxic effects of the antimalarial drug than the gastric cancer cell line PG100.


Asunto(s)
Antimaláricos , Antineoplásicos , Apoptosis/efectos de los fármacos , Artemisininas , Daño del ADN , Mutágenos , Antimaláricos/farmacología , Antimaláricos/toxicidad , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Arteméter , Artemisininas/farmacología , Artemisininas/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/patología , Microscopía Fluorescente , Mutágenos/farmacología , Mutágenos/toxicidad , Necrosis
18.
Int Braz J Urol ; 39(4): 542-50, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24054382

RESUMEN

OBJECTIVES: To evaluate the prevalence, distribution and association of HPV with histological pattern of worse prognosis of penile cancer, in order to evaluate its predictive value of inguinal metastasis, as well as evaluation of other previous reported prognostic factors. MATERIAL AND METHODS: Tumor samples of 82 patients with penile carcinoma were tested in order to establish the prevalence and distribution of genotypic HPV using PCR. HPV status was correlated to histopathological factors and the presence of inguinal mestastasis. The influence of several histological characteristics was also correlated to inguinal disease-free survival. RESULTS: Follow-up varied from 1 to 71 months (median 22 months). HPV DNA was identified in 60.9% of sample, with higher prevalence of types 11 and 6 (64% and 32%, respectively). There was no significant correlation of the histological characteristics of worse prognosis of penile cancer with HPV status. Inguinal disease-free survival in 5 years did also not show HPV status influence (p = 0.45). The only independent pathologic factors of inguinal metastasis were: stage T ≥ T1b-T4 (p = 0.02), lymphovascular invasion (p = 0.04) and infiltrative invasion (p = 0.03). CONCLUSIONS: HPV status and distribution had shown no correlation with worse prognosis of histological aspects, or predictive value for lymphatic metastasis in penile carcinoma.


Asunto(s)
Carcinoma/virología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Neoplasias del Pene/patología , Neoplasias del Pene/virología , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Carcinoma/patología , Carcinoma/secundario , Supervivencia sin Enfermedad , Humanos , Conducto Inguinal , Metástasis Linfática , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Riesgo , Factores de Tiempo , Adulto Joven
19.
BMC Gastroenterol ; 12: 85, 2012 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-22768805

RESUMEN

BACKGROUND: Gastric cancer is a serious public health problem in Northern Brazil and in the world due to its high incidence and mortality. Despite the severity of the disease, more research is needed to better understand the molecular events involved in this intestinal-type gastric carcinogenesis process. Since precancerous lesions precede intestinal-type gastric cancer, here, we evaluated the hTERT, MYC, and TP53 mRNA and protein expression, as well as TP33 copy number, in gastric preneoplastic lesions. METHODS: We evaluated 19 superficial gastritis, 18 atrophic gastritis, and 18 intestinal metaplasia from cancer-free individuals of Northern Brazil. Quantitative reverse transcription PCR was used to analyze the mRNA expression and immunohistochemical methods were used to assess protein immunoreactivity in tissue samples. The number of TP53 gene copies was investigated in gastric diseases by quantitative PCR. RESULTS: We observed hTERT, MYC, and p53 immunoreactivity only in intestinal metaplasia samples. The immunoreactivity of these proteins was strongly associated with each other. A significantly higher MYC mRNA expression was observed in intestinal metaplasia compared to gastritis samples. Loss of TP53 was also only detected in intestinal metaplasia specimens. CONCLUSIONS: We demonstrated that hTERT, MYC, and TP53 are deregulated in intestinal metaplasia of individuals from Northern Brazil and these alterations may facilitate tumor initiation.


Asunto(s)
Lesiones Precancerosas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Neoplasias Gástricas/metabolismo , Telomerasa/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Brasil , Transformación Celular Neoplásica/metabolismo , Femenino , Gastritis/genética , Gastritis/metabolismo , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Inmunohistoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Proteínas Proto-Oncogénicas c-myc/análisis , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Telomerasa/análisis , Proteína p53 Supresora de Tumor/análisis , Proteína p53 Supresora de Tumor/genética
20.
BMC Infect Dis ; 12: 119, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22591236

RESUMEN

BACKGROUND: Childhood pneumonia and bronchiolitis is a leading cause of illness and death in young children worldwide with Respiratory Syncytial Virus (RSV) as the main viral cause. RSV has been associated with annual respiratory disease outbreaks and bacterial co-infection has also been reported. This study is the first RSV epidemiological study in young children hospitalized with community-acquired pneumonia (CAP) in Belém city, Pará (Northern Brazil). METHODS: With the objective of determining the prevalence of RSV infection and evaluating the patients' clinical and epidemiological features, we conducted a prospective study across eight hospitals from November 2006 to October 2007. In this study, 1,050 nasopharyngeal aspirate samples were obtained from hospitalized children up to the age of three years with CAP, and tested for RSV antigen by direct immunofluorescence assay and by Reverse Transcription Polymerase Chain Reaction (RT-PCR) for RSV Group identification. RESULTS: RSV infection was detected in 243 (23.1%) children. The mean age of the RSV-positive group was lower than the RSV-negative group (12.1 months vs 15.5 months, p<0.001) whereas gender distribution was similar. The RSV-positive group showed lower means of C-reactive protein (CRP) in comparison to the RSV-negative group (15.3 vs 24.0 mg/dL, p<0.05). Radiological findings showed that 54.2% of RSV-positive group and 50.3% of RSV-negative group had interstitial infiltrate. Bacterial infection was identified predominantly in the RSV-positive group (10% vs 4.5%, p<0.05). Rhinorrhea and nasal obstruction were predominantly observed in the RSV-positive group. A co-circulation of RSV Groups A and B was identified, with a predominance of Group B (209/227). Multivariate analysis revealed that age under 1 year (p<0.015), CRP levels under 48 mg/dL (p<0.001) and bacterial co-infection (p<0.032) were independently associated with the presence of RSV and, in the analyze of symptoms, nasal obstruction were independently associated with RSV-positive group (p<0.001). CONCLUSION: The present study highlights the relevance of RSV infection in hospitalized cases of CAP in our region; our findings warrant the conduct of further investigations which can help design strategies for controlling the disease.


Asunto(s)
Infecciones Comunitarias Adquiridas/patología , Infecciones Comunitarias Adquiridas/virología , Neumonía Viral/patología , Neumonía Viral/virología , Infecciones por Virus Sincitial Respiratorio/patología , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/aislamiento & purificación , Brasil/epidemiología , Niño Hospitalizado , Infecciones Comunitarias Adquiridas/epidemiología , Estudios Transversales , Femenino , Técnica del Anticuerpo Fluorescente Directa , Humanos , Lactante , Masculino , Nasofaringe/virología , Neumonía Viral/epidemiología , Prevalencia , Estudios Prospectivos , Infecciones por Virus Sincitial Respiratorio/epidemiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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