To examine the effect of
(
) on the microenvironment of colonic neoplasms and the expression of inflammatory mediators and microRNAs (miRNAs).
Levels of
DNA, cytokine gene mRNA (
,
,
,
,
,
and
), and ...potentially interacting miRNAs (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p, miR-135b-5p) were measured by quantitative polymerase chain reaction (qPCR) TaqMan
assays in DNA and/or RNA extracted from the disease and adjacent normal fresh tissues of 27 colorectal adenoma (CRA) and 43 colorectal cancer (CRC) patients.
mutations were detected by direct sequencing and microsatellite instability (MSI) status by multiplex PCR. Cytoscape v3.1.1 was used to construct the postulated miRNA:mRNA interaction network.
Overabundance of
in neoplastic tissue compared to matched normal tissue was detected in CRA (51.8%) and more markedly in CRC (72.1%). We observed significantly greater expression of
,
,
, and miR-135b in CRA lesions and
,
,
,
, miR-34a and miR-135b in CRC tumours compared to their respective normal tissues. Only two transcripts for miR-22 and miR-28 were exclusively downregulated in CRC tumour samples. The mRNA expression of
,
,
and miR-22 was positively correlated with
quantification in CRC tumours. The mRNA expression of miR-135b and
was inversely correlated. The miRNA:mRNA interaction network suggested that the upregulation of miR-34a in CRC proceeds
a
/
-dependent response to
. Finally,
mutations were more frequently observed in CRC samples infected with
and were associated with greater expression of miR-21 in CRA, while
was upregulated in MSI-high CRC.
Our findings indicate that
is a risk factor for CRC by increasing the expression of inflammatory mediators through a possible miRNA-mediated activation of
/
.
There is increasing evidence indicating a role for
Fusobacterium nucleatum
(
F. nucleatum
) in colorectal cancer (CRC) development and prognosis. This study evaluated
F. nucleatum
as a prognostic ...biomarker, by assessing its association with post-diagnosis survival from CRC. From September 2008 to April 2012 CRC patients (
n
= 190) were recruited from three hospitals within the Czech Republic.
F. nucleatum
DNA copies were measured in adjacent non-malignant and colorectal tumor tissues using quantitative real-time PCR. Cox Proportional Hazards (HR) models were applied to evaluate the association between
F. nucleatum
DNA and overall survival, adjusting for key confounders. Risk prediction modeling was conducted to evaluate the ability to predict survival based on
F. nucleatum
status. High, compared with low, levels of
F. nucleatum
in colorectal tumor tissues were associated with poorer overall survival (adjusted HR 1.68, 95% CI 1.02–2.77), which was slightly attenuated after additional adjustment for microsatellite instability status. However, inclusion of
F. nucleatum
in risk prediction models did not improve the ability to identify patients who died beyond known prognostic factors such as disease pathology staging. Although the increased presence of
F. nucleatum
was associated with poorer prognosis in CRC patients, this may have limited clinical relevance as a prognostic biomarker.
TP53 genes is one of more important tumor suppressor gene, which acts as a potent transcription factor with fundamental role in the maintenance of genetic stability. The development of esophageal and ...gastric cancers is a multistep process resulting in successive accumulation of genetic alterations that culminates in the malignant transformation. Thus, this study highlights the participation of the main genetic alterations of the TP53 gene in esophageal and gastric carcinogenesis. Among these changes, high frequency of TP53 mutations, loss of heterozygosity (LOH), overexpression of the p53 protein, and consequently loss of p53 function, which would be early events in esophageal and gastric cancers, as well as an important biomarker of the prognosis and treatment response. Furthermore, Single Nucleotide Polymorphisms (SNPs) of TP53 have been implicated in the development and prognosis of several cancers, mainly TP53 codon 72 polymorphism whose role has been extensively studied in relation to susceptibility for esophageal and gastric cancer development.
To evaluate the effect of promoter region polymorphisms of toll-like receptor (TLR)2-196 to -174del and TLR4-1607T/C (rs10759932) on mRNA and protein expression in tumor tissue and of TLR4+896A/G ...(rs4986790) on colorectal cancer (CRC) risk.
The TLR2-196 to -174del polymorphism was investigated using allele-specific polymerase chain reaction (PCR) and the TLR4-1607T/C and TLR4+896A/G by PCR-restriction fragment length polymorphism (RFLP). We genotyped 434 DNA samples from 194 CRC patients and 240 healthy individuals. The mRNA relative quantification (RQ) was performed in 40 tumor tissue samples by quantitative PCR TaqMan assay, using specific probes for TLR2 and TLR4 genes, and ACTB and GAPDH reference genes were used as endogenous controls. Protein expression was analyzed by immunohistochemistry with specific primary antibodies.
No association was found for TLR4-1607T/C and TLR4+896A/G by three statistical models (log-additive, dominant and recessive). However, based on dominant and log-additive models, the polymorphic variant TLR2-196 to -174del was associated with increased CRC risk dominant: odds ratio (OR) = 1.72, 95%CI: 1.03-2.89; P = 0.038 and log-additive: OR =1.59, 95%CI: 1.02-2.48; P = 0.039. TLR2 mRNA expression was increased in tumor tissue (RQ = 2.36) when compared to adjacent normal tissue (RQ = 1; P < 0.0001), whereas the TLR4 mRNA showed a basal expression (RQ = 0.74 vs RQ = 1, P = 0.452). Immunohistochemistry analysis of TLR2 and TLR4 protein expression was concordant with the findings of mRNA expression. In addition, the TLR2-196 to -174del variant carriers showed mRNA relative expression 2.19 times higher than wild-genotype carriers. The TLR2 protein expression was also higher for the TLR2-196 to -174del variant carriers 117 ± 10 arbitrary unit (a.u.) vs 95 ± 4 a.u., P = 0.03. However, for the TLR4 -1607T/C polymorphism no significant difference was found for both mRNA (P = 0.56) and protein expression (P = 0.26).
Our findings suggest that TLR2-196 to -174del polymorphism increases TLR2 mRNA expression and is associated with higher CRC risk, indicating an important role in CRC genetic susceptibility.
Aim. To evaluate the prevalence and risk factors of H. pylori infection in the pediatric and adult population seen at a public hospital in São José do Rio Preto, SP, Brazil. Methods. This is a ...retrospective study that evaluated 2406 medical records of children, adolescents, and adults with dyspeptic symptoms who underwent upper gastrointestinal endoscopy. H. pylori diagnosis and demographic and clinical-pathological features were recorded. Results. A total of 852 subjects were H. pylori positive, with an overall prevalence of infection of 35.4%, occurring mainly in adults over 40 years of age, and a 24.7% prevalence considering only children and adolescents. No association was observed between H. pylori infection and risk factors. However, the H. pylori positive individuals showed a higher frequency of pangastritis (p<0.01), severe lesions (p=<0.001), and erosive lesions (p=0.04). The bacterium was eradicated in 83.5% (127) of the patients who received the standard therapy. Conclusions. The prevalence of H. pylori detected in a public service in São José do Rio Preto, SP, Brazil, is as expected for developed countries, showing growing rates with increasing age. As H. pylori infection occurs during childhood, screening programs for detection and prevention in the pediatric population are important to reduce the prevalence of this infection in adults.
AIM To investigate the contribution of polymorphisms in the CYP1A1, CYP2E1 and EPHX1 genes on sporadic colorectal cancer(SCRC) risk. METHODS Six hundred forty-one individuals(227 patients with SCRC ...and 400 controls) were enrolled in the study. The variables analyzed were age, gender, tobacco and alcohol consumption, and clinical and histopathological tumor parameters. The CYP1A1 *2A, CYP1A1 *2C CYP2E1 *5B and CYP2E1 *6 polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The EPHX1 Tyr113 His, EPHX1 His139 Arg and CYP1A1 *2C polymorphisms were detected by real-time PCR. Chisquared test and binary logistic regression were used in the statistical analysis. Haplotype analysis was conducted using the Haploview program, version 2.05.RESULTS Age over 6 2 years was a risk factor for SCRC development(OR = 7.54, 95%CI: 4.94-11.50, P < 0.01). Male individuals were less susceptible to SCRC(OR = 0.55, 95%CI: 0.35-0.85, P < 0.01). The CYP2E1*5B polymorphism was associated with SCRC in the codominant(heterozygous genotype: OR = 2.66, 95%CI: 1.64-4.32, P < 0.01), dominant(OR = 2.82, 95%CI: 1.74-4.55, P < 0.01), overdominant(OR = 2.58, 95%CI: 1.59-4.19, P < 0.01), and log-additive models(OR = 2.84, 95%CI: 1.78-4.52, P < 0.01). The CYP2E1*6 polymorphism was associated with an increased SCRC risk in codominant(heterozygous genotype: OR = 2.81, 95%CI: 1.84-4.28, P < 0.01; homozygous polymorphic : OR = 7. 3 2, 9 5 % C I : 1.85-28.96, P < 0.01), dominant(OR = 2.97, 95%CI: 1.97-4.50, P < 0.01), recessive(OR = 5.26, 95%CI: 1.35-20.50, P = 0.016), overdominant(OR = 2.64, 95%CI: 1.74-4.01, P < 0.01), and log-additive models(OR = 2.78, 95%CI: 1.91-4.06, P < 0.01). The haplotype formed by the minor alleles of the CYP2E1*5B(C) and CYP2E1*6(A) polymorphisms was associated with SCRC(P = 0.002). However, the CYP1A1 *2A, CYP1A1 *2C, EPHX1 Tyr113 His and EPHX1 His139 Arg polymorphisms were not associated with SCRC.CONCLUSION In conclusion, the results demonstrated that CYP2E1*5B and CYP2E1*6 minor alleles play a role in the development of SCRC.
Made available in DSpace on 2014-06-11T19:26:05Z (GMT). No. of bitstreams: 0
Previous issue date: 2013-02-25Bitstream added on 2014-06-13T19:53:59Z : No. of bitstreams: 1
proenca_ma_me_sjrp.pdf: ...521619 bytes, checksum: c975ed11c57b1194496e34885464bcca (MD5)
O câncer colorretal (CCR) é um dos modelos da associação inflamação-câncer. Assim, polimorfismos em genes que desempenham um papel importante na suscetibilidade a doenças inflamatórias, como os receptores Toll-like (TLR2 e TLR4), podem ser alvos interessantes para estudos de possíveis marcadores moleculares para CCR. Objetivos: Avaliar a associação dos polimorfismos TLR2 -196 a -174del, TLR4 -1607 T/C (rs10759932) e TLR4 +896 A/G (rs4986790), e de fatores de risco (gênero, idade, tabagismo e etilismo) com o desenvolvimento de CCR; assim como determinar os níveis de expressão relativa desses genes no tecido tumoral e a influência dos polimorfismos funcionais sobre os níveis de expressão do RNAm. Materiais e Métodos: Foram genotipadas 434 amostras (194 de pacientes com CCR e 240 de indivíduos saudáveis) de DNA de leucócitos de sangue periférico ou de células de tecido tumoral (DNA e RNA), por meio das técnicas de PCR alelo-específico e PCR-RFLP. A análise de regressão logística múltipla foi utilizada para avaliar a associação dos polimorfismos com risco de CCR, aplicando os modelos log-aditivo, dominante e recessivo, ajustados para os fatores de risco. Para a quantificação relativa (RQ) do RNAm foi utilizada a técnica de PCR quantitativa em tempo real (qPCR) em 40 amostras de tecido tumoral. Resultados: A variante polimórfica TLR2 -196 a -174del foi associada com risco aumentado de desenvolvimento de CCR de acordo com os modelos dominante (OR=1,72, IC95%=1,03-2,89; p=0,038) e log-aditivo (OR=1,59, IC95%=1,02-2,48; p=0,039), porém para os polimorfismos TLR4 -1607 T/C e TLR4 +896 A/G não foi encontrada associação. Idade acima de 60 anos (OR=1,83, IC95%=1,26-2,90; p=0,003) e hábito etilista (OR=2,78, IC95%=1,68-4,60; p=0,000) também estão associados com risco...
Colorectal cancer (CRC) is one of the models of inflammation-cancer association. Thus, polymorphisms in genes that play a role in susceptibility to inflammatory diseases, such as Toll-like receptors (TLR2 and TLR4) may be interesting targets for studies of potential molecular markers for CRC. Objectives: To evaluate the association of polymorphisms TLR2 -196 to -174del, TLR4 -1607 T/C (rs10759932) and TLR4 +896 A/G (rs4986790) and risk factors (gender, age, smoking and drinking habits) with CRC development, as well as to determine the relative expression levels of these genes in tumor tissue and influence of functional polymorphisms on the levels of mRNA expression. Materials and Methods: We genotyped 434 samples (194 patients with CRC and 240 from healthy individuals) of DNA from peripheral blood leukocytes or tumor tissue cells (DNA and RNA), by PCR allele-specific or PCR -RFLP. The multiple logistic regression analysis was performed to evaluate the association between the polymorphisms with risk of CRC, applying the log-additive, dominant and recessive models, adjusted for risk factors. The relative quantification (RQ) of the mRNA was performed by the real time quantitative PCR (qPCR) technique in 40 tumor tissue samples. Results: The polymorphic variant TLR2 -196 to -174del was associated with increased risk of developing CRC according to both dominant (OR=1.72, 95%CI=1.03 to 2.89, p=0.038) and log-additive models (OR=1.59, 95%CI=1.02 to 2.48, p=0.039), but for the TLR4 -1607 T/C and TLR4 +896 A/G polymorphisms no association was found. Age above 60 years old (OR=1.83, 95%CI=1.26 to 2.90, p=0.003) and alcohol consumption (OR=2.78, 95%CI=1.68 to 4.60, p=0.000) are also associated with increased risk for developing of this cancer. Analysis of relative quantification of the mRNA showed a... (Complete abstract click electronic access below)
Orientador: Ana Elizabete Silva
Coorientador: David J. Hughes
Banca: Marcelo Lima Ribeiro
Banca: Rui Manuel Vieira Reis
Banca: Débora Aparecida Pires de Campos Zuccari
Banca: Marilia De Freitas ...Calmon Saiki
Resumo: O câncer colorretal (CCR) está associado à patógenos como Fusobacterium nucleatum (Fn), que podem proporcionar um microambiente favorável para a tumorigênese em decorrência de alterações inflamatórias. Visando compreender o efeito de Fn no microambiente de lesões intestinais, avaliou-se a quantificação relativa (RQ) dessa bactéria em amostras de tecido de adenoma colorretal (ACR) e CCR, bem como sua correlação com a expressão de RNAm de mediadores inflamatórios (TLR2, TLR4, NFKB1, TNF, IL1B, IL6 e IL8) e de microRNAs (miRNAs) (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p e miR-135b-5p) envolvidos na resposta inflamatória e carcinogênese. Também delineou-se uma rede de interação miRNA:RNAm para auxiliar na compreensão da participação dos miRNAs no processo carcinogênico. Foram extraídos o DNA e o RNA de 27 amostras de tecido fresco de ACR e 43 de CCR e suas respectivas normais adjacentes. Os níveis de DNA de Fn e de RNAm dos mediadores inflamatórios e miRNAs foram quantificados por PCR quantitativo em tempo real (qPCR). Níveis elevados de Fn foram detectados em ACR (RQ=5,64) e mais acentuadamente em CCR (RQ=8,67). Observou-se expressão elevada do RNAm de TLR4, IL1B, IL8 e miR-135b em ACR, e de TLR2, IL1B, IL6, IL8, miR-34a e miR-135b em CCR em comparação com seus respectivos tecidos normais. Além disso, miR-22 e miR-28 foram encontrados com expressão reduzida em CCR. A expressão de RNAm de IL1B, IL6, IL8 e miR-22 foi positivamente correlacionada com a quantificação de Fn em CCR...
Abstract: Colorectal cancer (CRC) is associated with pathogens such as Fusobacterium nucleatum (Fn), which can provide a favorable microenvironment for tumorigenesis due to inflammatory changes. In order to understand the effect of Fn on the microenvironment of intestinal lesions, the relative quantification (RQ) of this bacterium was evaluated in samples of colorectal adenoma tissue (CRA) and CCR, as well as its correlation with the mRNA expression of inflammatory mediators (TLR2, TLR4, NFKB1, TNF, IL1B, IL6 e IL8), and microRNAs (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p e miR-135b-5p) involved in the inflammatory response and carcinogenesis. A miRNA: mRNA interaction network was also delineated to aid in the understanding of miRNA participation in the carcinogenic process. DNA and RNA were extracted from 27 fresh tissue samples of CRA and 43 of CRC and their respective adjacent normal ones. Fn and mRNA levels of the inflammatory mediators and miRNAs were quantified by quantitative real-time PCR (qPCR). Elevated levels of Fn were detected in CRA (RQ=5.64 and more markedly in CRC (RQ=8.67). High mRNA expression of TLR4, IL1B, IL8 and miR-135b in CRA, and of TLR2, IL1B, IL6, IL8, miR-34a and miR-135b in CRC were observed in comparison with their respective normal tissues. In addition, miR-22 and miR-28 were found downregulated in CRC. The mRNA expression of IL1B, IL6, IL8 and miR-22 was positively correlated with the quantification of Fn in CRC. The mRNA expression of miR-135b and ...
Doutor
PDF
