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1.
Cell Physiol Biochem ; 55(S2): 1-12, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33398982

RESUMO

BACKGROUND/AIMS: Lung carcinoids are uncommon neuroendocrine tumours. Molecular features of lung carcinoids have been poorly defined. microRNAs (miRNAs) are potent gene expression regulators with important roles in cancer development and progression. However, little is known on the role of miRNAs in the pathogenesis of lung carcinoids. Our goals were to identify commonly deregulated miRNAs in a rare case of lung carcinoid of typical histology with metastasis, as well as map miRNA target genes in pathways potentially associated with disease development and progression. METHODS: miRNA expression profiles were assessed using the TaqMan Low Density Arrays, which is a platform including 384 miRNAs. miRNA profiles were generated in the tumor and its corresponding lymph node metastasis, compared to reference normal lung tissues. Furthermore, miRNA expression was validated in a separate, publicly available external dataset (n=19 typical lung carcinoids; 2/19 were metastatic tumors, compared to six normal lung tissues, GSE77380). Following this analysis, computational tools were applied for data interpretation. miRTarBase was used to determine miRNA-target genes, followed by ToppGene Suite analysis to identify pathways and biological functions. In addition, the expression of genes targeted by miRNAs was validated in a second, separate external dataset (n=13 tumour samples, GSE35679). GEO2R data analysis tool was used in both validation analyses (miRNAs and genes). RESULTS: We identified 15 commonly significantly downregulated miRNAs (fold change, FC≥2 and p<0.05) in the tumour and its paired metastasis, with further decreasing levels in the metastatic lesion. Downregulation of miR-126-3p and miR-146b-5p was validated in the external dataset GSE77380. In addition, SOX2 and TCF4 genes, targeted by miR-126-3p, were consistently overexpressed in a subset of six typical lung carcinoids from the external dataset GSE35679. Pathways analysis showed that miRNAs miR-126-3p and miR-146b-5p target genes with a role in the regulation of adaptive immune response. CONCLUSION: Our results contribute to the identification of miRNA expression changes in a typical lung carcinoid and its corresponding lymph node metastasis. Down-regulated levels of miR-126-3p and miR-146b-5p and target gene over-expression could play a role in the progression of this case of primary typical lung carcinoid to regional metastasis. Identified miRNAs and target genes are potential candidates for validation in a larger number of cases.


Assuntos
Tumor Carcinoide/genética , Tumor Carcinoide/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , MicroRNAs/imunologia , Imunidade Adaptativa/genética , Adulto , Biomarcadores Tumorais/genética , Tumor Carcinoide/patologia , Biologia Computacional/métodos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática , MicroRNAs/genética , Estadiamento de Neoplasias
2.
Chromosoma ; 126(2): 313-323, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27169573

RESUMO

Supernumerary chromosomes have been studied in many species of eukaryotes, including the cichlid fish, Astatotilapia latifasciata. However, there are many unanswered questions about the maintenance, inheritance, and functional aspects of supernumerary chromosomes. The cichlid family has been highlighted as a model for evolutionary studies, including those that focus on mechanisms of chromosome evolution. Individuals of A. latifasciata are known to carry up to two B heterochromatic isochromosomes that are enriched in repetitive DNA and contain few intact gene sequences. We isolated and characterized a transcriptionally active repeated DNA, called B chromosome noncoding DNA (BncDNA), highly represented across all B chromosomes of A. latifasciata. BncDNA transcripts are differentially processed among six different tissues, including the production of smaller transcripts, indicating transcriptional variation may be linked to B chromosome presence and sexual phenotype. The transcript lengths and lack of similarity with known protein/gene sequences indicate BncRNA might represent a novel long noncoding RNA family (lncRNA). The potential for interaction between BncRNA and known miRNAs were computationally predicted, resulting in the identification of possible binding of this sequence in upregulated miRNAs related to the presence of B chromosomes. In conclusion, Bnc is a transcriptionally active repetitive DNA enriched in B chromosomes with potential action over B chromosome maintenance in somatic cells and meiotic drive in gametic cells.


Assuntos
Cromossomos , Ciclídeos/genética , RNA não Traduzido , Sequências Repetitivas de Ácido Nucleico , Transcrição Gênica , Animais , Análise por Conglomerados , Biologia Computacional/métodos , Evolução Molecular , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genômica/métodos , Masculino
3.
Chromosome Res ; 25(3-4): 277-290, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28776210

RESUMO

B chromosomes are dispensable elements observed in many eukaryotic species, including the African cichlid Astatotilapia latifasciata, which might have one or two B chromosomes. Although there have been many studies focused on the biology of these chromosomes, questions about the evolution, maintenance, and potential effects of these chromosomes remain. Here, we identified a variant form of the hnRNP Q-like gene inserted into the B chromosome of A. latifasciata that is characterized by a high copy number and intron-less structure. The absence of introns and presence of transposable elements with a reverse transcriptase domain flanking hnRNP Q-like sequences suggest that this gene was retroinserted into the B chromosome. RNA-Seq analysis did not show that the B variant retroinserted copies are transcriptionally active. However, RT-qPCR results showed variations in the canonical hnRNP Q-like copy expression levels among exons, tissues, sex, and B presence/absence. Although the patterns of transcription are not well understood, the exons of the B retrocopies were overexpressed, and a bias for female B+ expression was also observed. These results suggest that retroinsertion is an additional and important mechanism contributing to B chromosome formation. Furthermore, these findings indicate a bias towards female differential expression of B chromosome sequences, suggesting that B chromosomes and sex determination are somehow associated in cichlids.


Assuntos
Cromossomos , Ciclídeos/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Mutagênese Insercional , Animais , Evolução Molecular , Duplicação Gênica , Genoma , Genômica , Transcrição Gênica
4.
Nutr J ; 15: 20, 2016 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-26922244

RESUMO

BACKGROUND: High meat intake and low consumption of vegetables, fruits and whole grains have been associated with increased risk of colorectal cancer in some relevant cohort studies conducted in distinct ethnic populations. The role of the dietary pattern on the risk of sporadic colorectal adenocarcinoma (SCA) in Brazil is unknown; therefore, it was the aim of the present study. METHODS: The dietary patterns of 169 patients with SCA and 101 controls were analysed by food frequency recall. Crude odds ratios were calculated and given within 95 % confidence intervals. RESULTS: Patients reported higher average intakes of beef (32.0 ± 1.8 versus 23.7 ± 1.6, P = 0.0069), chicken (18.1 ± 0.9 versus 12.2 ± 0.8, P = 0.0002), and pork (8.9 ± 0.9 versus 3.4 ± 0.5, P < 0.0001). These individuals had a 1.025, 1.069, and 1.121-fold increased risk of SCA. Similar consumption of fish, vegetables, fruits and whole grains was reported by patients and controls. CONCLUSIONS: Meat consumption is greater in patients with SCA in the Brazilian population. Considering the study population - characterized by ethnic heterogeneity -, the environmental factor related to food habits may be associated with higher incidence of this disease in Brazil.


Assuntos
Neoplasias Colorretais/epidemiologia , Dieta , Comportamento Alimentar , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Frutas , Humanos , Incidência , Masculino , Carne , Pessoa de Meia-Idade , Fatores de Risco , Verduras , Grãos Integrais
5.
Arq Gastroenterol ; 61: e23148, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511796

RESUMO

BACKGROUND: Latent tuberculosis (LTB) is a condition where the patient is infected with Mycobacterium tuberculosis but does not develop active TB. There's a possibility of tuberculosis (TB) activation following the introduction of anti-TNFs. OBJECTIVE: To assess the risk of biological therapy inducing LTB during inflammatory bowel diseases (IBD) treatment over 15 years in a high-risk area in Brazil. METHODS: A retrospective study of an IBD patients' database was carried out in a private reference clinic in Brazil. All patients underwent TST testing and chest X-ray prior to treatment, and once a year after starting it. Patients were classified according to the Montreal stratification and risk factors were considered for developing TB. RESULTS: Among the analyzed factors, age and gender were risk factors for LTB. DC (B2 and P) and UC (E2) patients showed a higher number of LTB cases with statistical significance, what was also observed for adalimumab and infliximab users, compared to other medications, and time of exposure to them favored it significantly. Other factors such as enclosed working environment have been reported as risk. CONCLUSION: The risk of biological therapy causing LTB is real, so patients with IBD should be continually monitored. This study reveals that the longer the exposure to anti-TNFs, the greater the risk. BACKGROUND: •Rate of infection (tuberculosis) in Brazilians IBD private patients: follow-up 15 years. BACKGROUND: •Patients treated with immunosuppressants and/or anti-TNFs have a higher risk of developing opportunistic infections, among them the most common is latent tuberculosis or even active tuberculosis. BACKGROUND: •Similar risks may be noted in patients with inflammatory bowel diseases (IBDs). BACKGROUND: •This study reveals that the longer the exposure to anti-TNFs, the greater the risk for de IBD patients. BACKGROUND: •The study demonstrated the importance of monitoring these patients permanently and continuously.


Assuntos
Doenças Inflamatórias Intestinais , Tuberculose Latente , População da América do Sul , Tuberculose , Humanos , Brasil/epidemiologia , Seguimentos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/tratamento farmacológico , Tuberculose Latente/diagnóstico , Tuberculose Latente/microbiologia , Estudos Retrospectivos , Teste Tuberculínico , Inibidores do Fator de Necrose Tumoral
6.
Toxics ; 12(3)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38535945

RESUMO

Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 µg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15-177%, p = 0.010) and 95.9% (95%CI 16-230.8%, p = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin.

7.
Cancers (Basel) ; 12(9)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971741

RESUMO

(1) Background: Although the advances in diagnostic and treatment strategies, lung cancer remains the leading cause of cancer-related deaths, worldwide, with survival rates as low as 16% in developed countries. Low survival rates are mainly due to late diagnosis and the lack of effective treatment. Therefore, the identification of novel, clinically useful biomarkers is still needed for patients with advanced disease stage and poor survival. Micro(mi)RNAs are non-coding RNAs and potent regulators of gene expression with a possible role as diagnostic, prognostic and predictive biomarkers in cancer. (2) Methods: We applied global miRNA expression profiling analysis using TaqMan® arrays in paired tumor and normal lung tissues (n = 38) from treatment-naïve patients with lung adenocarcinoma (AD; n = 23) and lung squamous cell carcinoma (SCC; n = 15). miRNA target genes were validated using The Cancer Genome Atlas (TCGA) lung AD (n = 561) and lung SCC (n = 523) RNA-Seq datasets. (3) Results: We identified 33 significantly deregulated miRNAs (fold change, FC ≥ 2.0 and p < 0.05) in tumors relative to normal lung tissues, regardless of tumor histology. Enrichment analysis confirmed that genes targeted by the 33 miRNAs are aberrantly expressed in lung AD and SCC, and modulate known pathways in lung cancer. Additionally, high expression of miR-25-3p was significantly associated (p < 0.05) with poor patient survival, when considering both tumor histologies. (4) Conclusions: miR-25-3p may be a potential prognostic biomarker in non-small cell lung cancer. Genes targeted by miRNAs regulate EGFR and TGFß signaling, among other known pathways relevant to lung tumorigenesis.

8.
Arq. gastroenterol ; 61: e23148, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557113

RESUMO

ABSTRACT Background: Latent tuberculosis (LTB) is a condition where the patient is infected with Mycobacterium tuberculosis but does not develop active TB. There's a possibility of tuberculosis (TB) activation following the introduction of anti-TNFs. Objective: To assess the risk of biological therapy inducing LTB during inflammatory bowel diseases (IBD) treatment over 15 years in a high-risk area in Brazil. Methods: A retrospective study of an IBD patients' database was carried out in a private reference clinic in Brazil. All patients underwent TST testing and chest X-ray prior to treatment, and once a year after starting it. Patients were classified according to the Montreal stratification and risk factors were considered for developing TB. Results: Among the analyzed factors, age and gender were risk factors for LTB. DC (B2 and P) and UC (E2) patients showed a higher number of LTB cases with statistical significance, what was also observed for adalimumab and infliximab users, compared to other medications, and time of exposure to them favored it significantly. Other factors such as enclosed working environment have been reported as risk. Conclusion: The risk of biological therapy causing LTB is real, so patients with IBD should be continually monitored. This study reveals that the longer the exposure to anti-TNFs, the greater the risk.


RESUMO Contexto: A tuberculose latente (TBL) é uma condição em que o paciente está infectado com Mycobacterium tuberculosis, mas não desenvolve tuberculose (TB) ativa. Existe a possibilidade de ativação da TB após a introdução de anti-TNFs. Objetivo: Avaliar o risco da terapia biológica induzindo TBL durante o tratamento de doenças inflamatórias intestinais (DII) ao longo de 15 anos em uma área de alto risco no Brasil. Métodos: Foi realizado um estudo retrospectivo de um banco de dados de pacientes com DII em uma clínica privada de referência no Brasil. Todos os pacientes foram submetidos a teste de TST e radiografia de tórax antes do tratamento e uma vez por ano após seu início. Os pacientes foram classificados de acordo com a estratificação de Montreal e foram considerados fatores de risco para o desenvolvimento de TB. Resultados: Entre os fatores analisados, a idade e o sexo foram fatores de risco para TBL. Os pacientes com doença de Crohn' (B2 e P) e colite ulcerativa (E2) apresentaram maior número de casos de TBL com significância estatística, o que também foi observado para usuários de adalimumab e infliximab, em comparação com outros medicamentos, e o tempo de exposição a eles favoreceu significativamente. Outros fatores, como ambiente de trabalho fechado, foram relatados como riscos. Conclusão: O risco da terapia biológica causar TBL é real, por isso os pacientes com DII devem ser monitorados continuamente. Este estudo revela que quanto maior a exposição aos anti-TNFs, maior o risco.

9.
PLoS One ; 14(5): e0217421, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150430

RESUMO

Despite progress in treatment strategies, only ~24% of pancreatic ductal adenocarcinoma (PDAC) patients survive >1 year. Our goal was to elucidate deregulated pathways modulated by microRNAs (miRNAs) in PDAC and Vater ampulla (AMP) cancers. Global miRNA expression was identified in 19 PDAC, 6 AMP and 25 paired, histologically normal pancreatic tissues using the GeneChip 4.0 miRNA arrays. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated pathways. Target gene expression was validated in 178 pancreatic cancer and 4 pancreatic normal tissues from The Cancer Genome Atlas (TCGA). 20 miRNAs were significantly deregulated (FC≥2 and p<0.05) (15 down- and 5 up-regulated) in PDAC. miR-216 family (miR-216a-3p, miR-216a-5p, miR-216b-3p and miR-216b-5p) was consistently down-regulated in PDAC. miRNA-modulated pathways are associated with innate and adaptive immune system responses in PDAC. AMP cancers showed 8 down- and 1 up-regulated miRNAs (FDR p<0.05). Most enriched pathways (p<0.01) were RAS and Nerve Growth Factor signaling. PDAC and AMP display different global miRNA expression profiles and miRNA regulated networks/tumorigenesis pathways. The immune response was enriched in PDAC, suggesting the existence of immune checkpoint pathways more relevant to PDAC than AMP.


Assuntos
Imunidade Adaptativa/genética , Carcinoma Ductal Pancreático/genética , Imunidade Inata/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Adulto , Idoso , Ampola Hepatopancreática/patologia , Carcinoma Ductal Pancreático/patologia , Biologia Computacional , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/imunologia , Redes Reguladoras de Genes/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Regulação para Cima
10.
Oncotarget ; 7(20): 28920-34, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27081085

RESUMO

Herein, we aimed at identifying global transcriptome microRNA (miRNA) changes and miRNA target genes in lung adenocarcinoma. Samples were selected as training (N = 24) and independent validation (N = 34) sets. Tissues were microdissected to obtain >90% tumor or normal lung cells, subjected to miRNA transcriptome sequencing and TaqMan quantitative PCR validation. We further integrated our data with published miRNA and mRNA expression datasets across 1,491 lung adenocarcinoma and 455 normal lung samples. We identified known and novel, significantly over- and under-expressed (p ≤ 0.01 and FDR≤0.1) miRNAs in lung adenocarcinoma compared to normal lung tissue: let-7a, miR-10a, miR-15b, miR-23b, miR-26a, miR-26b, miR-29a, miR-30e, miR-99a, miR-146b, miR-181b, miR-181c, miR-421, miR-181a, miR-574 and miR-1247. Validated miRNAs included let-7a-2, let-7a-3, miR-15b, miR-21, miR-155 and miR-200b; higher levels of miR-21 expression were associated with lower patient survival (p = 0.042). We identified a regulatory network including miR-15b and miR-155, and transcription factors with prognostic value in lung cancer. Our findings may contribute to the development of treatment strategies in lung adenocarcinoma.


Assuntos
Adenocarcinoma/genética , Redes Reguladoras de Genes/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Transcriptoma , Adenocarcinoma/mortalidade , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição/genética
11.
Arq. neuropsiquiatr ; 58(3A): 713-9, set. 2000.
Artigo em Português | LILACS | ID: lil-269621

RESUMO

A hipertermia maligna caracteriza-se por hipertermia, rigidez muscular, rabdomiólise, acidose e insuficiência de múltiplos órgaos. A hipertermia maligna anestésica decorre da exposiçao a halogenados e/ou relaxantes musculares despolarizantes. O método padrao para diagnosticar a suscetibilidade à hipertermia maligna é o teste da contratura muscular in vitro em resposta ao halotano e à cafeína. A síndrome maligna por neurolépticos caracteriza-se por hipertermia, síndrome extrapiramidal, acidose, instabilidade neurovegetativa e alteraçoes neurológicas. Descrevemos três pacientes com síndrome maligna por neurolépticos e testes de contratura muscular positivos. Esse achado demonstra que ocasionalmente o músculo de pacientes com síndrome maligna por neurolépticos pode mostrar as alteraçoes encontradas na hipertermia maligna anestésica


Assuntos
Humanos , Adulto , Masculino , Feminino , Hipertermia Maligna/diagnóstico , Síndrome Maligna Neuroléptica/complicações , Cafeína , Contratura , Suscetibilidade a Doenças , Halotano , Hipertermia Maligna/etiologia
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