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1.
Int J Mol Sci ; 23(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35054834

RESUMO

Gastric cancer (GC) is the fifth most common type of cancer and the third leading cause of cancer death in the world. It is a disease that encompasses a variety of molecular alterations, including in non-coding RNAs such as circular RNAs (circRNAs). In the present study, we investigated hsa_circ_0000211, hsa_circ_0000284, hsa_circ_0000524, hsa_circ_0001136 and hsa_circ_0004771 expression profiles using RT-qPCR in 71 gastric tissue samples from GC patients (tumor and tumor-adjacent samples) and volunteers without cancer. In order to investigate the suitability of circRNAs as minimally invasive biomarkers, we also evaluated their expression profile through RT-qPCR in peripheral blood samples from patients with and without GC (n = 41). We also investigated the predicted interactions between circRNA-miRNA-mRNA and circRNA-RBP using the KEGG and Reactome databases. Overall, our results showed that hsa_circ_0000211, hsa_circ_0000284 and hsa_circ_0004771 presented equivalent expression profiles when analyzed by different methods (RNA-Seq and RT-qPCR) and different types of samples (tissue and blood). Further, functional enrichment results identified important signaling pathways related to GC. Thus, our data support the consideration of circRNAs as new, minimally invasive biomarkers capable of aiding in the diagnosis of GC and with great potential to be applied in clinical practice.


Assuntos
Biomarcadores Tumorais/genética , Redes Reguladoras de Genes , RNA Circular/sangue , Neoplasias Gástricas/diagnóstico , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Detecção Precoce de Câncer , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , RNA-Seq , Neoplasias Gástricas/sangue , Neoplasias Gástricas/genética
2.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36498907

RESUMO

Emerging deep learning-based applications in precision medicine include computational histopathological analysis. However, there is a lack of the required training image datasets to generate classification and detection models. This phenomenon occurs mainly due to human factors that make it difficult to obtain well-annotated data. The present study provides a curated public collection of histopathological images (DeepHP) and a convolutional neural network model for diagnosing gastritis. Images from gastric biopsy histopathological exams were used to investigate the performance of the proposed model in detecting gastric mucosa with Helicobacter pylori infection. The DeepHP database comprises 394,926 histopathological images, of which 111 K were labeled as Helicobacter pylori positive and 283 K were Helicobacter pylori negative. We investigated the classification performance of three Convolutional Neural Network architectures. The models were tested and validated with two distinct image sets of 15% (59K patches) chosen randomly. The VGG16 architecture showed the best results with an Area Under the Curve of 0.998%. The results showed that CNN could be used to classify histopathological images from gastric mucosa with marked precision. Our model evidenced high potential and application in the computational pathology field.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Humanos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/patologia , Mucosa Gástrica/patologia , Gastrite/diagnóstico , Gastrite/patologia , Gastroscopia/métodos
3.
Pathobiology ; 88(2): 156-169, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33588422

RESUMO

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.


Assuntos
Microbioma Gastrointestinal/genética , Neoplasias Gástricas/microbiologia , Biologia Computacional , Mucosa Gástrica/microbiologia , Microbioma Gastrointestinal/fisiologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Humanos , Redes e Vias Metabólicas , Metagenoma , Prevotella/genética , Prevotella/patogenicidade
4.
BMC Immunol ; 21(1): 60, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213373

RESUMO

BACKGROUND: The forkhead box protein 3 (FOXP3) transcription factor is one of the main markers of immunological suppression in different pathological profiles, and the presence of polymorphic variants may alter the gene expression of this factor. Despite descriptions of an association between the presence of the rs2232365 polymorphism and chronic diseases, the role of the sex variant in this context has not yet been elucidated, as the FOXP3 gene is located on the human sex chromosome X. RESULTS: To contribute to this topic, 323 women and 373 men were enrolled in the study, of which 101 were diagnosed with chronic viral liver diseases (39 women and 62 men), 67 with HTLV-1 infection (44 women and 23 men), 230 with coronary artery disease (91 women and 139 men) and 298 healthy and uninfected blood donors (149 women and men). They were genotyped for the rs2232365 polymorphism. The rs2232365 polymorphism was associated with clinical and pathological aspects and biomarkers of viral infections only in men, with functional differences between different infections. CONCLUSIONS: A relationship is suggested between sex and FOXP3 rs2232365 polymorphism, resulting in different biological repercussions.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Genótipo , Infecções por HTLV-I/genética , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Fatores Sexuais , Adulto , Estudos de Casos e Controles , Doença Crônica , Doença da Artéria Coronariana/genética , Feminino , Fatores de Transcrição Forkhead/genética , Predisposição Genética para Doença , Infecções por HTLV-I/imunologia , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
5.
Mol Med ; 26(1): 12, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996124

RESUMO

BACKGROUNDS: Neural growth factor (NGF) is a neurotrophin that can interact with the p75NTR receptor and initiate a cascade of reactions that determines cell survival or death, and both are associated with the physiology of liver tissue. Single nucleotide polymorphisms (SNPs) in the NGF and p75NTR genes have been investigated in different pathologies; however, there are no studies that have analyzed their biological roles in the hepatic microenvironment. In the present study, we evaluated the impact of SNPs in these genes on the maintenance of liver function at different stages of inflammation and fibrosis in patients with chronic viral liver disease in the Brazilian Amazon. METHODS: The SNPs -198C > T, Arg80Gln, Val72Met, Ala35Val, Ala18Ala and Ser205Leu were genotyped by real-time PCR in samples from patients with chronic viral hepatitis stratified by stage of inflammation and liver fibrosis. Histopathological, viral load (VL), liver enzyme and comorbidities data were obtained from updated medical records. Other aspects were highlighted by applied epidemiological questionnaires. RESULTS: The -198C/T and Ala35Val polymorphisms in NGF were associated with changes in histopathological profiles, VL and liver enzymes. Ser205Leu polymorphism in p75NTR was associated only with changes in VL and liver enzymes. Polymorphic frequencies were variable among different ethnic populations, mainly for biologically relevant polymorphisms. A multifactorial network of interactions has been established based on genetic, virological, behavioral and biochemical aspects. CONCLUSION: Mutations in the NGF (-198C > T, Ala35Val) and p75NTR (Ser205Leu) genes, within the list of multifactorial aspects, are associated with liver function in different histopathological profiles of patients with chronic viral liver disease in the Brazilian Amazon.


Assuntos
Substituição de Aminoácidos , Hepatite Viral Humana/fisiopatologia , Fator de Crescimento Neural/genética , Proteínas do Tecido Nervoso/genética , Receptores de Fator de Crescimento Neural/genética , Estudos Transversais , Feminino , Hepatite Viral Humana/genética , Hepatite Viral Humana/virologia , Humanos , Testes de Função Hepática , Masculino , Polimorfismo de Nucleotídeo Único , Carga Viral
6.
Int J Mol Sci ; 21(20)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081152

RESUMO

Gastric cancer (GC) represents a notable amount of morbidity and mortality worldwide. Understanding the molecular basis of CG will offer insight into its pathogenesis in an attempt to identify new molecular biomarkers to early diagnose this disease. Therefore, studies involving small non-coding RNAs have been widely explored. Among these, PIWI-interacting RNAs (piRNAs) are an emergent class that can play important roles in carcinogenesis. In this study, small-RNA sequencing was used to identify the global piRNAs expression profile (piRNome) of gastric cancer patients. We found 698 piRNAs in gastric tissues, 14 of which were differentially expressed (DE) between gastric cancer (GC), adjacent to gastric cancer (ADJ), and non-cancer tissues (NC). Moreover, three of these DE piRNAs (piR-48966*, piR-49145, piR-31335*) were differently expressed in both GC and ADJ samples in comparison to NC samples, indicating that the tumor-adjacent tissue was molecularly altered and should not be considered as a normal control. These three piRNAs are potential risk biomarkers for GC, especially piR-48966* and piR-31335*. Furthermore, an in-silico search for mRNAs targeted by the differentially expressed piRNAs revealed that these piRNAs may regulate genes that participate in cancer-related pathways, suggesting that these small non-coding RNAs may be directly and indirectly involved in gastric carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , RNA Interferente Pequeno/genética , Neoplasias Gástricas/genética , Transcriptoma , Biomarcadores Tumorais/metabolismo , Redes Reguladoras de Genes , Humanos , Metástase Neoplásica , RNA Interferente Pequeno/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
7.
BMC Gastroenterol ; 18(1): 30, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466950

RESUMO

BACKGROUND: Anal residual tumors are consensually identified within six months of chemoradiotherapy and represent a persistent lesion that may have prognostic value for overall survival. The aim of this study was to evaluate the association of HPV and HIV status, p16 expression level and TP53 mutations with the absence of residual tumors (local response) in Squamous Cell Carcinoma (SCC) of the anal canal after chemoradiotherapy. METHODS: We performed a study on 78 patients with SCC of the anal canal who submitted to chemoradiotherapy and were followed for a six-month period to identify the absence or presence of residual tumors. HPV DNA was identified by polymerase chain reaction and direct sequencing, HIV RNA was detected by TaqMan amplification, p16 expression was detected by western blotting, and the mutational analysis of TP53 was performed by direct sequencing; additionally, samples carrying mutations underwent fluorescent in sit hybridization. The evaluation of the tumor response to treatment was conducted six months after the conclusion of chemoradiotherapy. The following classifications were used to evaluate the outcomes: a) no response (presence of residual tumor) and b) complete response (absence of residual tumor). RESULTS: The significant variables associated with the absence of residual tumors were HPV positive, p16 overexpressed, wild-type TP53, female gender, and stages I and II. Only the presence of HPV was independently correlated with the clinical response; this variable increased the chances of a response within six months by 31-fold. CONCLUSIONS: The presence of HPV in tumor cells was correlated with the absence of a residual tumor. This correlation is valuable and can direct future therapeutic approaches in the anal canal.


Assuntos
Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , DNA Viral/análise , Genes p16 , Neoplasia Residual , Papillomaviridae/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/genética , Neoplasias do Ânus/patologia , Neoplasias do Ânus/virologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Feminino , Expressão Gênica , Genótipo , HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Resultado do Tratamento
8.
Chin J Cancer Res ; 30(5): 564-567, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30510368

RESUMO

The search for cancer biomarkers is frequently based on comparisons between tumors and adjacent-to-tumor samples. However, even after histological confirmation of been free of cancer cells, these adjacent-to-tumor samples might harbor molecular alterations which are not sufficient to cause them to look like cancer, but can differentiate these cells from normal cells. When comparing them, potential biomarkers are missed, and mainly the opportunity of finding initial aberrations presents in both tumors and adjacent samples, but not in true normal samples from non-cancer patients, resulting in misinterpretations about the carcinogenic process. Nevertheless, collecting adjacent-to-tumor samples brings trumps to be explored. The addition of samples from non-cancer patients opens an opportunity to increase the finds of the molecular cascade of events in the carcinogenic process. Differences between normal samples and adjacent samples might represent the first steps of the carcinogenic process. Adding samples of non-cancer patients to the analysis of molecular alterations relevant to the carcinogenic process opens a new window of opportunities to the discovery of cancer biomarkers and molecular targets.

9.
J Cell Biochem ; 118(4): 869-877, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27748538

RESUMO

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.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Genes Supressores de Tumor , Histonas/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Acetilação , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Diferenciação Celular/genética , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/farmacologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Neoplasias Gástricas/tratamento farmacológico
10.
Mediators Inflamm ; 2017: 3718451, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28408790

RESUMO

The present study investigated the frequencies of rs1800450 (MBL ⁎B, G>A), rs1800451 (MBL ⁎C, G>A), and rs5030737 (MBL ⁎D, C>T) polymorphisms in exon 1 of the MBL2 gene among patients with chronic viral hepatitis. Blood samples from patients infected with hepatitis B virus (HBV; n = 65), hepatitis C virus (HCV; n = 92), and a noninfected control group (n = 300) were investigated. The presence of polymorphisms was detected using a real-time polymerase chain reaction to correlate with liver disease pathogenesis and fibrosis staging according to the Metavir classification. The genotypic and allelic frequencies showed no significant differences between the groups, but patients with active HBV and the wild AA genotype presented a positive correlation between increased transaminase and HBV DNA levels and the presence of mild to moderate fibrosis. Patients with HCV and the wild AA genotype presented mild inflammation and higher HCV RNA levels, although the same association was not observed for the fibrosis scores. The results suggest that the mutations in exon 1 of the MBL2 gene do not contribute directly to the clinical and laboratory features of HCV and HBV infections, but further studies should be performed to confirm whether the wild AA genotype has indirect effect on disease progression.


Assuntos
Vírus da Hepatite B/patogenicidade , Fígado/enzimologia , Fígado/virologia , Lectina de Ligação a Manose/metabolismo , Carga Viral/fisiologia , Adulto , Idoso , Estudos Transversais , Éxons/genética , Feminino , Frequência do Gene/genética , Frequência do Gene/fisiologia , Genótipo , Vírus da Hepatite B/genética , Humanos , Fígado/metabolismo , Masculino , Lectina de Ligação a Manose/genética , Pessoa de Meia-Idade
11.
Neuropathology ; 36(1): 3-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26303046

RESUMO

Severe dengue disease is often associated with long-term neurological impairments, but it is unclear what mechanisms are associated with neurological sequelae. Previously, we demonstrated antibody-enhanced dengue disease (ADE) dengue in an immunocompetent mouse model with a dengue virus 2 (DENV2) antibody injection followed by DENV3 virus infection. Here we migrated this ADE model to Callithrix penicillata. To mimic human multiple infections of endemic zones where abundant vectors and multiple serotypes co-exist, three animals received weekly subcutaneous injections of DENV3 (genotype III)-infected supernatant of C6/36 cell cultures, followed 24 h later by anti-DENV2 antibody for 12 weeks. There were six control animals, two of which received weekly anti-DENV2 antibodies, and four further animals received no injections. After multiple infections, brain, liver, and spleen samples were collected and tissue was immunolabeled for DENV3 antigens, ionized calcium binding adapter molecule 1, Ki-67, TNFα. There were marked morphological changes in the microglial population of ADE monkeys characterized by more highly ramified microglial processes, higher numbers of trees and larger surface areas. These changes were associated with intense TNFα-positive immunolabeling. It is unclear why ADE should generate such microglial activation given that IgG does not cross the blood-brain barrier, but this study reveals that in ADE dengue therapy targeting the CNS host response is likely to be important.


Assuntos
Sistema Nervoso Central/patologia , Dengue/patologia , Inflamação/patologia , Animais , Anticorpos Antivirais/toxicidade , Barreira Hematoencefálica/patologia , Callithrix , Vírus da Dengue/imunologia , Hipocampo/patologia , Imuno-Histoquímica , Microglia/patologia , Fator de Necrose Tumoral alfa/metabolismo
12.
Mediators Inflamm ; 2015: 150673, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26347404

RESUMO

Toll-like receptor 4 (TLR4) plays a crucial role in the early recognition of pathogenic microorganisms and provides an ideal model to investigate the consequences of genetic variation and susceptibility to diseases. The present study investigated the occurrence of the single nucleotide polymorphisms (SNPs) rs4986790 (A>G) and rs4986791 (C>T) in the TLR4 gene in chronic carriers of the hepatitis B (HBV) and C (HCV) viruses. A total of 420 blood samples were collected (HBV, 49; HCV, 72; and controls, 299) at the liver disease outpatient clinic of Hospital da Fundação Santa Casa de Misericórdia do Pará (FSCMPA). Genomic DNA extracted from leukocytes was subjected to real-time polymerase chain reaction (qPCR) analysis to identify the genetic profile of the participants. No significant differences were found in the allele and genotype frequencies between the infected participants and controls. No significant associations were found between the investigated polymorphisms and inflammatory activity, fibrosis, and the presence of cirrhosis; the same results were obtained in the haplotype analysis. The results showed a lack of association between the rs4986790 and rs4986791 SNPs and susceptibility to infection with HBV and HCV, as well as clinical and laboratory information of the patients.


Assuntos
Hepatite B/genética , Hepatite C/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor 4 Toll-Like/genética , Adulto , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade
13.
Tumour Biol ; 35(4): 3447-53, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24338710

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/genética , RNA Mensageiro/análise , Neoplasias Gástricas/etiologia , Adulto , Idoso , Ilhas de CpG , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
14.
Tumour Biol ; 35(7): 6373-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24668547

RESUMO

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.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/administração & dosagem , Ácidos Hidroxâmicos/administração & dosagem , RNA Mensageiro/biossíntese , Neoplasias Gástricas/enzimologia , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes myc/genética , Histona Desacetilase 1/biossíntese , Histona Desacetilase 1/genética , Histona Desacetilase 2/biossíntese , Histona Desacetilase 2/genética , Histona Desacetilases/biossíntese , Histona Desacetilases/genética , Humanos , RNA Mensageiro/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ativação Transcricional/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/biossíntese , Fatores de Transcrição de p300-CBP/genética
15.
BMC Gastroenterol ; 14: 9, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24410879

RESUMO

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.


Assuntos
Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética , Adulto , Nucléolo Celular/química , Núcleo Celular/química , Feminino , Mucosa Gástrica/metabolismo , Gastrite/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Nucleares/análise , Proteínas Nucleares/metabolismo , Nucleofosmina , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
16.
Cytokine ; 61(3): 940-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23395388

RESUMO

OBJECTIVE: The present paper investigated possible correlations between the clinical presentation of hepatitis B and the TNF-α -308G/A, IFN-γ +874A/T, TGF-beta1 -509C/T, and IL-10 -1081A/G polymorphisms and associated serum levels of these cytokines. METHODS: Fifty-three hepatitis patients were selected and divided into two groups: A - inactive (n=30) and B - chronic hepatitis/cirrhosis (n=23). The control group consisted of 100 subjects who were positive for anti-HBc and anti-HBs. The serum concentrations of the cytokines were determined by immunoenzymatic assays. The polymorphisms of the cytokines genes were assessed by PCR and PCR-SSP. RESULTS: The mean serum levels of IFN-γ of the control group were significantly higher than those of groups A and B, whereas the mean levels TGF-beta1 were significantly higher in groups A and B in comparison with the control. In the case of IL-10, the mean serum level recorded in the control group was significantly higher than that of group B. The TNF-α -308AG genotype was considerably more frequent in group B (43.3%) than the control (14.4%). CONCLUSION: Higher serum levels of IFN-γ and TGF-beta1 were associated with chronic hepatitis B, and lower serum levels of IL-10 were found in patients with the active disease. Furthermore the presence of allele A of the TNF-α -308 polymorphism suggest a risk of the progressive disease.


Assuntos
Citocinas/sangue , Citocinas/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Hepatite B Crônica/sangue , Hepatite B Crônica/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Frequência do Gene/genética , Humanos , Interferon gama/sangue , Interferon gama/genética , Interleucina-10/sangue , Interleucina-10/genética , Fator de Crescimento Transformador beta1/sangue , Fator de Crescimento Transformador beta1/genética , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética
17.
BMC Gastroenterol ; 13: 141, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24053468

RESUMO

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.


Assuntos
Adenocarcinoma/genética , Proteínas de Ciclo Celular/genética , Variações do Número de Cópias de DNA , Proteínas F-Box/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc/genética , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/cirurgia , Adulto , Idoso , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD , Feminino , Perfilação da Expressão Gênica , Humanos , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-myc/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirurgia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
Genet Mol Biol ; 36(1): 22-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23569404

RESUMO

Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-C(Asp80) gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-C(Asp80) (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.

19.
Mem Inst Oswaldo Cruz ; 107(8): 1021-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23295753

RESUMO

Because an enriched environment (EE) enhances T-cell activity and T-lymphocytes contribute to immunopathogenesis during heterologous dengue virus (DENV) infections, we hypothesised that an EE increases dengue severity. To compare single serotype (SS) and antibody-enhanced disease (AED) infections regimens, serial intraperitoneal were performed with DENV3 (genotype III) infected brain homogenate or anti-DENV2 hyperimmune serum followed 24 h later by DENV3 (genotype III) infected brain homogenate. Compared AED for which significant differences were detected between the EE and impoverished environmental (IE) groups (Kaplan-Meyer log-rank test, p = 0.0025), no significant differences were detected between the SS experimental groups (Kaplan-Meyer log-rank test, p = 0.089). Survival curves from EE and IE animals infected with the AED regimen were extended after corticoid injection and this effect was greater in the EE than in the IE group (Kaplan-Meyer log-rank test, p = 0.0162). Under the AED regimen the EE group showed more intense clinical signs than the IE group. Dyspnoea, tremor, hunched posture, ruffled fur, immobility, pre-terminal paralysis, shock and death were associated with dominant T-lymphocytic hyperplasia and presence of viral antigens in the liver and lungs. We propose that the increased expansion of these memory T-cells and serotype cross-reactive antibodies facilitates the infection of these cells by DENV and that these events correlate with disease severity in an EE.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Animais , Linfócitos B/imunologia , Dengue/virologia , Ecologia , Feminino , Ativação Linfocitária/imunologia , Camundongos , Linfócitos T/imunologia
20.
Eur J Ophthalmol ; 32(6): NP36-NP40, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34142579

RESUMO

PURPOSE: To describe a case of a patient presenting with acquired acoria and iris pearls, a rare eye manifestation and pathognomonic finding for leprosy; to reinforce clinical, histopathological, and therapeutic aspects of ocular involvement in leprosy. METHODS: Case report. CASE DESCRIPTION: A 62-year-old male presenting with acquired acoria and iris pearls in both eyes due to leprosy also had anterior uveitis and cataract. Histopathological diagnosis of iris pearls was confirmed by the presence of Hansen's bacilli. Ophthalmological examination revealed improvement of the visual acuity after iridectomy and extracapsular cataract extraction. CONCLUSIONS: To our knowledge, this is the first reported case of acquired acoria in a leprosy patient. It led to impaired vision and reversible blindness. Proper diagnosis and ophthalmological treatment of patients with these conditions are essential for the maintenance of a good quality of life.


Assuntos
Catarata , Hanseníase , Humanos , Iris/cirurgia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Acuidade Visual
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