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1.
Anticancer Res ; 42(9): 4381-4394, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36039443

RESUMO

BACKGROUND/AIM: Previous studies from our research group have shown that trisomy 8 and the amplification of the 8q24.21 region is very frequent in gastric cancer (GC). Little is known about the role of most genes located in this region. Thus, the aim of this study was to understand the possible impact of transcriptional alterations and copy number variation (CNV) of four genes located in the 8q24.21 region - FAM49B, FAM84B, GSDMC and miR-5194 - in GC. MATERIALS AND METHODS: Fifty-one to 85 matched pairs of tumoral and adjacent non-tumoral gastric tissues, from patients with primary GC, were used to analyze gene expression and CNV of the selected genes. We also included 29 H. pylori negative and gastritis negative gastric mucosa tissues from individuals without cancer obtained by endoscopy, as control samples. RESULTS: The expression of FAM49B, GSDMC and miR-5194 was higher in both tumoral and adjacent non-tumoral samples compared to the negative control. The expression of FAM84B showed no significant difference between tumoral samples and negative controls. However, the expression of FAM84B in the adjacent non-tumoral samples was higher compared to negative control and tumoral samples. Moreover, the higher expression of GSDMC was associated with T3 and T4 tumors, with tumors on stage III and IV and with advanced tumors. Higher copy numbers of FAM49B and GSDMC were associated with intestinal tumor type and with moderately or well-differentiated tumors. Higher copy number of FAM84B was associated with moderately or well-differentiated tumors. Furthermore, the expression of all four genes was positively correlated. CONCLUSION: All four genes are upregulated in GC and may play an important role in these neoplasms. GSDMC expression was associated with more aggressive tumors.


Assuntos
MicroRNAs , Neoplasias Gástricas , Biomarcadores Tumorais/genética , Cromossomos Humanos Par 8 , Variações do Número de Cópias de DNA/genética , Proteínas de Ligação a DNA/genética , Mucosa Gástrica/patologia , Humanos , MicroRNAs/genética , Proteínas Citotóxicas Formadoras de Poros , Neoplasias Gástricas/patologia
2.
Epigenetics ; 17(1): 110-116, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33491552

RESUMO

Gastric cancer (GC) is one of the leading types of fatal cancer worldwide. Epigenetic manipulation of cancer cells is a useful tool to better understand gene expression regulatory mechanisms and contributes to the discovery of novel biomarkers. Our research group recently reported a list of 83 genes that are potentially modulated by DNA methylation in GC cell lines. Herein, we further explored the regulation of one of these genes, LRRC37A2, in clinical samples. LRRC37A2 expression was evaluated by RT-qPCR, and DNA methylation was studied using next-generation bisulphite sequencing in 36 GC and paired adjacent nonneoplastic tissue samples. We showed that both reduced LRRC37A2 mRNA levels and increased LRRC37A2 exon methylation were associated with undifferentiated and poorly differentiated tumours. Moreover, LRRC37A2 gene expression and methylation levels were inversely correlated at the +45 exon CpG site. We suggest that DNA hypermethylation may contribute to reducing LRRC37A2 expression in undifferentiated and poorly differentiated GC. Therefore, our results show how some genes may be useful to stratify patients who are more likely to benefit from epigenetic therapy.Abbreviations: AR: androgen receptor; 5-AZAdC: 5-aza-2'-deoxycytidine; B2M: beta-2-microglobulin; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GC: gastric cancer; GLM: general linear model; LRRC37A2: leucine-rich repeat containing 37 member A2; SD: standard deviation; TFII-I: general transcription factor II-I; TSS: transcription start site; XBP1: X-box binding protein 1.


Assuntos
Metilação de DNA , Neoplasias Gástricas , Linhagem Celular Tumoral , Ilhas de CpG , Decitabina , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
3.
J Mol Med (Berl) ; 98(5): 707-717, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32285140

RESUMO

Gastric cancer (GC) is the third leading cause of cancer-related death worldwide. Very few therapeutic options are currently available in this neoplasia. The use of 5-Aza-2'-deoxycytidine (5-AZAdC) was approved for the treatment of myelodysplastic syndromes, and this drug can treat solid tumours at low doses. Epigenetic manipulation of GC cell lines is a useful tool to better understand gene expression regulatory mechanisms for clinical applications. Therefore, we compared the gene expression profile of 5-AZAdC-treated and untreated GC cell lines by a microarray assay. Among the genes identified in this analysis, we selected NRN1 and TNFAIP3 to be evaluated for gene expression by RT-qPCR and DNA methylation by bisulfite DNA next-generation sequencing in 43 and 52 pairs of GC and adjacent non-neoplastic tissue samples, respectively. We identified 83 candidate genes modulated by DNA methylation in GC cell lines. Increased expression of NRN1 and TNFAIP3 was associated with advanced tumours (P < 0.05). We showed that increased NRN1 and TNFAIP3 expression seems to be regulated by DNA demethylation in GC samples: inverse correlations between the mRNA and DNA methylation levels in the promoter of NRN1 (P < 0.05) and the intron of TNFAIP3 (P < 0.05) were detected. Reduced NRN1 promoter methylation was associated with III/IV TNM stage tumours (P = 0.03) and the presence of Helicobacter pylori infection (P = 0.02). The identification of demethylated activated genes in GC may be useful in clinical practice, stratifying patients who are less likely to benefit from 5-AZAdC-based therapies. KEY MESSAGES: Higher expression of NRN1 and TNFAIP3 is associated with advanced gastric cancer (GC). NRN1 promoter hypomethylation contributes to gene upregulation in advanced GC. TNFAIP3 intronic-specific CpG site demethylation contributes to gene upregulation in GC. These findings may be useful to stratify GC patients who are less likely to benefit from DNA demethylating-based therapies.


Assuntos
Desmetilação do DNA , Regulação Neoplásica da Expressão Gênica , Neuropeptídeos/genética , Neoplasias Gástricas/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Azacitidina/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Biologia Computacional/métodos , Ilhas de CpG , Metilação de DNA , Decitabina/farmacologia , Epigênese Genética , Proteínas Ligadas por GPI/genética , Perfilação da Expressão Gênica , Humanos , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/patologia , Transcriptoma
4.
Future Med Chem ; 11(9): 947-958, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31141411

RESUMO

Aim: To analyze gene expression and copy number of five miRNAs (miR-1204, miR-1205, miR-1206, miR-1207 and miR-1208) localized in this chromosome region in gastric cancer (GC). Materials & methods: 65 paired neoplastic and non-neoplastic specimens collected from GC patients and 20 non-neoplastic gastric tissues from cancer-free individuals were included in this study. The expression levels of the five miRNAs were accessed by real time qPCR and were correlated. Results: MiR-1207-3p, miR-1205, miR-1207-5p and miR-1208 were upregulated in approximately 50% of GC tumors in relation to those of adjacent non-neoplastic tissues. MiR-1205 expression was associated with gain of gene copies and was upregulated in adjacent non-neoplastic samples relative to external controls. Conclusion: The coexpression of the 8q24 miRNAs indicated the role of miR-1205 in the initiation of gastric cancer development.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Gástricas/genética , Adulto , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Regulação para Cima
5.
Acta Cir Bras ; 32(3): 236-242, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28403348

RESUMO

PURPOSE:: To evaluate the effect of remote ischemic preconditioning (r-IPC) administered to pregnant rats, in the ileum of newborn rats subjected to hypoxia and reoxygenation. METHODS:: We used three pregnant rats and their newborn rats distributed in three groups: 1) Control (C) - Newborn rats born from a pregnant rat which did not undergo any intervention; 2) Hypoxia-Reoxygenation (H/R) - Newborn rats born from a pregnant rat which did not undergo any intervention, and were subjected to hypoxia-reoxygenation; 3) Remote Ischemic Preconditioning (r-IPC) - newborn rats born from a pregnant rat which was subjected to remote ischemic preconditioning twenty-four hours before giving birth and the newborn rats were subjected to hypoxia-reoxygenation. Segments of ileum were prepared for histological analysis by HE and immunohistochemistry by the Ki67 to evaluate cell proliferation, crypt depth and villus height and evaluation of apoptosis by cleaved caspase-3. RESULTS:: The intensity of the lesions was lower in the r-IPC than in the H/R group, showing significant difference (p<0.01). The r-IPC group showed a higher proliferative activity compared to the H/R group (p<0.01), with deeper crypts (r-IPC > H/R - p < 0.05), and higher villi, showing significant difference (r-IPC > H/R - (p <0.01). The occurrence of apoptosis in the H/R group was lower in comparison to groups C and r-IPC, with significant difference (H/R < r-IPC; p<0.05). CONCLUSION:: The remote ischemic preconditioning applied to the pregnant rat protected the ileum of newborn rats subjected to hypoxia and reoxygenation, with decreased intensity of the lesions in the ileum mucosa and preservation of proliferative activity, keeping the villus height and crypt depth similar to group C.


Assuntos
Enterocolite Necrosante/prevenção & controle , Íleo/irrigação sanguínea , Precondicionamento Isquêmico/métodos , Animais , Animais Recém-Nascidos , Apoptose , Caspase 3/análise , Hipóxia Celular , Modelos Animais de Doenças , Enterocolite Necrosante/patologia , Feminino , Íleo/patologia , Imuno-Histoquímica , Mucosa Intestinal/irrigação sanguínea , Antígeno Ki-67/análise , Gravidez , Ratos , Traumatismo por Reperfusão/prevenção & controle , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
7.
Clin Exp Med ; 17(1): 121-129, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26567008

RESUMO

CDKN1A is a tumor suppressor gene involved in gastric carcinogenesis and is a potential target for histone deacetylase inhibitor-based therapies. Upregulation of CDKN1A is generally observed in several cell lines after histone deacetylase inhibitor treatment; however, little is known about the histone acetylation status associated with this gene in clinical samples, including gastric tumor tissue samples. Therefore, our goal was to quantify the H3K9 and H4K16 acetylation levels associated with three CDKN1A regions in 21 matched pairs of gastric adenocarcinoma and corresponding adjacent non-tumor samples by chromatin immunoprecipitation and to correlate these data with the gene expression. Our results demonstrated that the -402, -20, and +182 CDKN1A regions showed a significantly increased acetylation level in at least one of the histones evaluated (p < 0.05, for all comparisons), and these levels were positively correlated in gastric tumors. However, an inverse correlation was detected between both H3K9 and H4K16 acetylation at the -402 CDKN1A region and mRNA levels in gastric tumors (r = -0.51, p = 0.02; r = -0.60, p < 0.01, respectively). Furthermore, increased H4K16 acetylation at the -20 CDKN1A region was associated with gastric tumors of patients without lymph node metastasis (p = 0.04). These results highlight the complexity of these processes in gastric adenocarcinoma and contribute to a better understanding of CDKN1A regulation in carcinogenesis.


Assuntos
Adenocarcinoma/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Neoplasias Gástricas/genética , Acetilação , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Imunoprecipitação da Cromatina , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Epigênese Genética , Feminino , Histonas/metabolismo , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
8.
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
9.
Arq Gastroenterol ; 53(1): 55-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27281506

RESUMO

BACKGROUND: Morbid obesity treatment through vertical gastroplasty Roux-en-Y gastric bypass initially used a contention ring. However, this technique may create conditions to the development of potentially malign alterations in the gastric mucosa. Although effective and previously performed in large scale, this technique needs to be better evaluated in long-term studies regarding alterations caused in the gastric mucosa. OBJECTIVE: To analyze the preoperative and postoperative endoscopic, histological and cell proliferation findings in the gastric antrum and body mucosa of patients submitted to the Roux-en-Y gastric bypass with a contention ring. METHODS: We retrospectively evaluated all patients submitted to Roux-en-Y gastric bypass with a contention ring with more than 60 months of postoperative follow-up. We compared the preoperative (gastric antrum and body) and postoperative (gastric pouch) gastric mucosa endoscopic findings, cell proliferation index and H. pylori prevalence. We evaluated cell proliferation through Ki-67 antibody immunohistochemical expression. RESULTS: In the study period, 33 patients were operated with the Roux-en-Y gastric bypass using a contention ring. We found a chronic gastritis rate of 69.7% in the preoperative period (gastric antrum and body) and 84.8% in the postoperative (gastric pouch). H. pylori was present in 18.2% of patients in the preoperative period (gastric antrum and body) and in 57.5% in the postoperative (gastric pouch). Preoperative cell proliferation index was 18.1% in the gastric antrum and 16.2% in the gastric body, and 23.8% in the postoperative gastric pouch. The postoperative cell proliferation index in the gastric pouch was significantly higher (P=0.001) than in the preoperative gastric antrum and body. Higher cell proliferation index and chronic gastritis intensity were significantly associated to H. pylori presence (P=0.001 and P=0.02, respectively). CONCLUSION: After Roux-en-Y gastric bypass with contention ring, there was a higher chronic gastritis incidence and higher cell proliferation index in the gastric pouch than in the preoperative gastric antrum and body. Mucosa inflammation intensity and cell proliferation index in the postoperative gastric pouch were associated to H. pylori presence and were higher than those found in the preoperative gastric antrum and body mucosa.


Assuntos
Derivação Gástrica/métodos , Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Obesidade Mórbida/cirurgia , Adulto , Anastomose em-Y de Roux , Proliferação de Células , Doença Crônica , Estudos Transversais , Feminino , Derivação Gástrica/efeitos adversos , Mucosa Gástrica/patologia , Gastrite/patologia , Infecções por Helicobacter/etiologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
J Gastrointest Cancer ; 47(1): 20-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26585943

RESUMO

PURPOSE: Gastritis caused by infection with Helicobacter pylori is characterized by chronic inflammation and damage in gastric tissue, which is a main risk factor for gastric cancer. Associated with H. pylori, the TP53 gene tumor suppressor and the cell adhesion glycoprotein epithelial cadherin develop a relevant role in the integrity and carcinogenesis of the epithelium. We aimed to detection of H. pylori and its main virulence markers and measured the messenger RNA (mRNA) expression levels of E-cadherin and TP53 genes. METHODS: The detection of H. pylori and its virulence markers, as well as the mRNA expression levels of E-cadherin and TP53 genes, were obtained for 161 samples of gastric biopsies including 37 with normal gastric tissue, 70 with gastritis, 24 from neoplastic tissue, and 27 from adjacent non-neoplastic by means of a quantitative real-time polymerase chain reaction. RESULTS: The mRNA expression levels of E-cadherin and TP53 were found to be decreased in patients with gastritis, independently of H. pylori infection. In samples from gastric patients, the neoplastic tissue showed an accentuated decrease of expression; on the other hand, the expression of E-cadherin was normal in adjacent non-neoplastic. CONCLUSIONS: No evidence was found of the involvement of the cagA and vacA genes in the decreased expression of E-cadherin and TP53. The process of carcinogenesis is complex, and the decrease of the E-cadherin gene expression and TP53 gene expression appears to contribute significantly.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Biomarcadores/análise , Caderinas/genética , Infecções por Helicobacter/genética , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Virulência/genética , Adulto , Estudos de Casos e Controles , DNA Viral/genética , Regulação para Baixo , Feminino , Seguimentos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Gastrite/genética , Gastrite/patologia , Gastrite/virologia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/patologia , Infecções por Helicobacter/virologia , Helicobacter pylori , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Taxa de Sobrevida
13.
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
14.
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
15.
Appl. cancer res ; 31(3): 81-86, 2011. ilus, tab
Artigo em Inglês | LILACS, Inca | ID: lil-652796

RESUMO

OBJECTIVE: To study part of the Wnt signaling pathway for carcinogenesis in colorectal cancer and polyps, through adenomatous polyposis coli (APC) and β-catenin protein expression. METHODS: We studied the immunoexpression of APC protein and β-catenin in the adenocarcinoma and polyps (adenoma) from ninety-one patients who underwent resection of sporadic colorectal cancer (CRC) with curative intent from 1993 to 2004 at the Hospital do Câncer de Barretos (Brazil). Each patient was resected within a period 3 months before or after diagnosis. The polyps or adenocarcinoma was considered positive for APC when more than 10% of the cells showed cytoplasmic staining and for β-catenin when more than 5% of the cells showed nuclear stainning. RESULTS: Among the 91 patients, we found association among APC protein expression in the polyps and in the respective colorectal adenocarcinoma (p = 0.014). Similarly, there were significant association with nuclear expressions (p = 0.001) of β-catenin in the polyps and colorectal adenocarcinoma. Nuclear β-catenin expression was associated with villous adenoma (86%, p = 0.042). There was no association among APC and β-catenin expression and any other histological finding. CONCLUSION: There is an association of APC and β-catenin protein expression in polyps and in colorectal adenocarcinoma. This finding allows us to speculate that in the same patient the same WNT pathway or another is activated in both lesions; polyp and adenocarcinoma. Villous adenomas occur most frequently via the Wnt signaling pathway.


Assuntos
Humanos , Caderinas , Neoplasias Colorretais , Neoplasias Colorretais Hereditárias sem Polipose , Polipose Adenomatosa do Colo , Polipose Intestinal
16.
Arq. gastroenterol ; 45(4): 295-300, out.-dez. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-502139

RESUMO

BACKGROUND: Crohn's disease accompanied by nonspecific or idiopathic ulcerative proctocolitis corresponds to a condition called intestinal inflammatory disease. The immunoexpression of cyclooxygenase 2 (COX-2) in Crohn's disease becomes more marked with progression of the disease and the presence of wild-type p53 suppresses the transcription of COX-2. AIMS: To investigate the immunoexpression of cyclooxygenase 1 (COX-1), COX-2 and p53 in Crohn's ileocolitis and to correlated this expression with clinical and histopathological parameters. METHODS: Forty-five cases of Crohn's disease, 16 cases of actinic colitis (diseased-control group) and 11 cases without a history of intestinal disease (normal control group) were studied. Hematoxylin-eosin-stained sections were submitted to histopathological analysis and the immunohistochemical expression of COX-1, COX-2 and p53 was evaluated by the streptavidin-biotin-peroxidase method. RESULTS: Sixty percent of the Crohn's disease patients were women and 40 percent were men, with 75.5 percent whites and 25.5 percent non-whites. The disease involved the terminal ileum in 44.5 percent of cases, ileum in 33.3 percent, colon in 20 percent and duodenum-ileum in 2.2 percent. A significant association was observed between COX-2 immunoreactivity and age <40 years. Histopathological analysis of Crohn's disease samples showed mild or moderate crypt distortion (57.8 percent and 35.6 percent of cases), atrophy (6.6 percent), mild, moderate and marked chronic inflammation (46.7 percent, 26.7 percent and 20 percent), acute inflammatory activity (93.3 percent), ulceration (24.4 percent), mucin depletion (37.8 percent), Paneth's cells (24.4 percent), intraepithelial lymphocytes (93.3 percent), and subepithelial collagen (6.7 percent). In the CD group, COX-1 immunoreactivity in epithelial and inflammatory cells was observed in 26.7 percent and 22.2 percent of cases, respectively. COX-2 immunoreactivity was detected...


RACIONAL: A doença de Crohn, junto com a colite ulcerativa idiopática ou inespecífica constituem a doença inflamatória intestinal. A imunoexpressão de ciclooxigenase 2 (COX-2) na doença de Crohn acentua-se com a progressão da doença, enquanto que a presença do tipo selvagem de p53 suprime a transcrição de COX-2. OBJETIVOS: Investigar a imunoexpressão de ciclooxigenase 1 (COX-1), COX-2 e p53 na doença de Crohn e correlacionar os achados com parâmetros clínico-histopatológicos. MÉTODOS: Foram estudados 45 casos de doença de Crohn (grupo teste), 16 casos de colite actínica (grupo controle-doente) e 11 casos sem história de doença intestinal (grupo controle normal). A avaliação histopatológica foi feita com lâminas coradas pela hematoxilina-eosina e a imunoexpressão de COX-1, COX-2 e p53 foi avaliada por imunoistoquímica, pelo método da estrepto-avidina-biotina-peroxidase. RESULTADOS: Entre os pacientes com doença de Crohn, 60 por cento eram do sexo feminino e 40 por cento do masculino, 75,5 por cento brancos e 25,5 por cento não-brancos. A doença comprometia o íleo terminal em 44,5 por cento dos casos, íleo em 33,3 por cento, cólon em 20 por cento e duodeno-íleo em 2,2 por cento. Associação significante foi detectada entre a imunoexpressão de COX-2 e pacientes com <40 anos. A histopatologia dos casos de doença de Crohn mostrou distorção críptica em grau leve ou moderado (57,8 por cento e 35,6 por cento dos casos), atrofia (6,6 por cento), inflamação focal, difusa superficial e difusa transmural (46,7 por cento, 26,7 por cento e 20 por cento), inflamação aguda neutrofílica (93,3 por cento), alterações epiteliais: ulceração (24,4 por cento), depleção de mucina (37,8 por cento), células de Paneth (24,4 por cento); alterações epiteliais associadas: linfócitos intra-epiteliais (93,3 por cento) e colágeno subepitelial (6,7 por cento). No grupo doença de Crohn, imunoexpressão de COX-1, em células epiteliais e inflamatórias foi observada em 26,7...


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Colite Ulcerativa/metabolismo , Doença de Crohn/metabolismo , Ciclo-Oxigenase 1/metabolismo , /metabolismo , Ileíte/metabolismo , /metabolismo , Estudos de Casos e Controles , Colite Ulcerativa/enzimologia , Colite Ulcerativa/etiologia , Colite Ulcerativa/patologia , Doença de Crohn/enzimologia , Doença de Crohn/etiologia , Doença de Crohn/patologia , Células Epiteliais/metabolismo , Imuno-Histoquímica , Ileíte/enzimologia , Ileíte/patologia , Radioterapia/efeitos adversos , Adulto Jovem
17.
Arq Gastroenterol ; 45(4): 295-300, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19148357

RESUMO

BACKGROUND: Crohn's disease accompanied by nonspecific or idiopathic ulcerative proctocolitis corresponds to a condition called intestinal inflammatory disease. The immunoexpression of cyclooxygenase 2 (COX-2) in Crohn's disease becomes more marked with progression of the disease and the presence of wild-type p53 suppresses the transcription of COX-2. AIMS: To investigate the immunoexpression of cyclooxygenase 1 (COX-1), COX-2 and p53 in Crohn's ileocolitis and to correlated this expression with clinical and histopathological parameters. METHODS: Forty-five cases of Crohn's disease, 16 cases of actinic colitis (diseased-control group) and 11 cases without a history of intestinal disease (normal control group) were studied. Hematoxylin-eosin-stained sections were submitted to histopathological analysis and the immunohistochemical expression of COX-1, COX-2 and p53 was evaluated by the streptavidin-biotin-peroxidase method. RESULTS: Sixty percent of the Crohn's disease patients were women and 40% were men, with 75.5% whites and 25.5% non-whites. The disease involved the terminal ileum in 44.5% of cases, ileum in 33.3%, colon in 20% and duodenum-ileum in 2.2%. A significant association was observed between COX-2 immunoreactivity and age < or =40 years. Histopathological analysis of Crohn's disease samples showed mild or moderate crypt distortion (57.8% and 35.6% of cases), atrophy (6.6%), mild, moderate and marked chronic inflammation (46.7%, 26.7% and 20%), acute inflammatory activity (93.3%), ulceration (24.4%), mucin depletion (37.8%), Paneth's cells (24.4%), intraepithelial lymphocytes (93.3%), and subepithelial collagen (6.7%). In the CD group, COX-1 immunoreactivity in epithelial and inflammatory cells was observed in 26.7% and 22.2% of cases, respectively. COX-2 immunoreactivity was detected in epithelial cells in 68.9% of cases and in inflammatory cells in 46.7%. A marginal difference in COX-2 reactivity was observed between epithelial and inflammatory cells in association with acute inflammatory activity and increase in intraepithelial lymphocytes. Comparison of the date among the threes groups (Crohn's disease, actinic colitis and normal controls) showed a higher proportion of cases presenting COX-2 immunoreactivity in inflammatory cells in the Crohn's disease group. No p53 reactivity was observed in all cases. CONCLUSIONS: COX-2 immunoexpression is high in Crohn's disease, which suggest a possible role of the protein in the pathogenesis of the inflammation. The absence of epithelial dysplasia in all Crohn's disease samples was correlated with the lack of expression of p53.


Assuntos
Colite Ulcerativa/metabolismo , Doença de Crohn/metabolismo , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ileíte/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Colite Ulcerativa/enzimologia , Colite Ulcerativa/etiologia , Colite Ulcerativa/patologia , Doença de Crohn/enzimologia , Doença de Crohn/etiologia , Doença de Crohn/patologia , Células Epiteliais/metabolismo , Feminino , Humanos , Ileíte/enzimologia , Ileíte/patologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Radioterapia/efeitos adversos , Adulto Jovem
18.
J. bras. patol. med. lab ; 43(5): 355-361, set.-out. 2007. ilus, tab
Artigo em Português | LILACS | ID: lil-471120

RESUMO

OBJETIVO: Avaliar a relação de duas proteínas que participam do mecanismo de adesão celular com o grau de diferenciação celular e os estadiamentos TNM (T: tumor, N: linfonodo, M: metástase) I e IV no câncer de cólon e reto. MÉTODOS: Foram estudados cem pacientes (54 homens e 46 mulheres) tratados por adenocarcinoma colorretal, estádios I (44) e IV (56). Os cortes histológicos do tecido tumoral foram examinados por técnica de imuno-histoquímica em relação à imunoexpressão das proteínas caderina-E e delect in colon cancer (DCC), sendo classificados como positivos quando se detectou a imunoexpressão dessas proteínas em 50 por cento ou mais das células tumorais. RESULTADOS: Para o TNM, imunoexpressão da caderina-E estádio I: positiva em 72,7 por cento e negativa em 35,7 por cento ; estádio IV: positiva em 64,3 por cento e negativa em 35,7 por cento. Proteína DCC: 43,2 por cento positiva e 56,8 por cento negativa no estádio I, e 50 por cento positiva e 50 por cento negativa no estádio IV. Em relação ao grau de diferenciação celular, imunoexpressão da caderina-E - GI: positiva em 70 por cento e negativa em 30 por cento; GII: positiva em 68,4 por cento e 31,6 por cento negativa; GIII: 63,6 por cento positiva e 36,4 por cento negativa. Imunoexpressão da DCC - GI: 40 por cento positiva e 60 por cento negativa; GII: 46,8 por cento positiva e 53,2 por cento negativa; GIII: 54,5 por cento positiva e 45,5 por cento negativa. Não houve diferença significativa entre os grupos. CONCLUSÃO: Os resultados dessa pesquisa permitem concluir que não há relação da imunoexpressão das proteínas caderina-E e DCC com o estadiamento TNM (I e IV) e o grau de diferenciação celular no carcinoma colorretal.


OBJECTIVE: Evaluate the relationship of two proteins, which take part in the same mechanism of cell adhesion, with the cell differentiation degree and TNM staging I and IV in colorectal cancer. METHODS: One-hundred patients (54 men and 46 women), who have received treatment for colorectal cancer, stages I (44) and IV (56), have been studied. Histological cuts of tumor tissue were examined by the immunohistochemical technique as to the expression of E-cadherin and delect in colon cancer (DCC) proteins, being classified as positive whenever it was detected immunoexpression of such proteins in 50 percent or more tumor cells. RESULTS: For TNM, E-cadherin immunoexpression for stage I: positive in 72.7 percent and negative in 35.7 percent; stage IV: positive in 64.3 percent and negative in 35.7 percent. For DCC protein: 43.2 percent positive and 56.8 percent negative in stage I, and 50 percent positive and 50 percent negative in stage IV. Regarding the cell differentiation degree, the immunoexpression of E-cadherin - GI: positive in 70 percent and negative in 30 percent; GII: positive in 68.4 percent and negative in 31.6 percent; GIII: positive in 63.6 percent and negative in 36.4 percent. The immunoexpression of DCC - GI: 40 percent positive and 60 percent negative; GII: 46.8 percent positive and 53.2 percent negative; GIII: 54.5 percent positive and 45.5 percent negative. There was no significant difference among groups. CONCLUSION: The results of this research make it possible to come to the conclusion that there is no relationship between the immunoexpression of E-cadherin and DCC proteins with TNM staging (I and IV) and cell differentiation degree in colorectal cancer.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adenocarcinoma/genética , Diferenciação Celular , Caderinas/genética , Genes DCC/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , Estadiamento de Neoplasias , Estudos Retrospectivos
19.
Microsurgery ; 27(4): 282-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17477410

RESUMO

Morphometric evaluation of the fetal intestinal graft in the late post-transplant period was done by using C57BL/6 mice. Under anesthesia, after hysterotomy, a transversal laparotomy was done in the fetus to harvest all intestines. Grafts, cleaned from its mesentery, and divided were transplanted into the preperitoneum space, from male mice, C57BL/6 strain. Thirty days after, mice were killed, and the graft was analyzed with HE stain and S-100 protein. All grafts as well as fetal and adult intestines were evaluated as controls. All developed grafts showed muscular layer and positivity for S-100 protein as the adult intestines. The goblet cells, absent in fetal intestines, were in larger number in isogeneic grafts than in adult intestines, even with lower villus. These findings showed sharp progress of the isogeneic graft from fetal to adult intestine, suggesting that they can be viable and might be functionally appropriate in the late period after transplantation.


Assuntos
Intestino Delgado/patologia , Intestino Delgado/transplante , Animais , Sobrevivência de Enxerto , Intestino Delgado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas S100/metabolismo , Fatores de Tempo , Transplante Homólogo
20.
Microsurgery ; 26(1): 61-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16444724

RESUMO

We investigated histopathological changes following murine fetal intestinal transplantation. Fetal intestine, obtained from a pregnant C57BL/6 mouse, was transplanted into BALB/c and C57Bl/6 mice. Recipients were divided into three groups: isogeneic, and allogeneic treated with 3 mg/kg/day gangliosides (Allo-a) or 9 mg/kg/day (Allo-b). One week after transplant, all grafts showed good viability, confirmed by cellular mitosis in the mucosa and a well-defined propria muscular layer. Isogeneic grafts showed a thicker muscular layer than in the Allo-a (P = 0.02) and Allo-b (P = 0.004) groups. There was no difference in number of mitotic cells among groups. Goblet cells were significantly reduced in allografts treated with 3 mg gangliosides (P = 0.013) or 9 mg gangliosides (P = 0.002) compared to isografts. Villi height was similar in all studied groups. There was no difference in positivity of the enteric nervous system among groups. Atrophy was more common in the allogeneic groups, suggesting that isografts had better development than allografts treated with gangliosides. (


Assuntos
Transplante de Tecido Fetal/patologia , Gangliosídeos/fisiologia , Intestino Delgado/patologia , Intestino Delgado/transplante , Animais , Feminino , Transplante de Tecido Fetal/imunologia , Sobrevivência de Enxerto , Intestino Delgado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas S100/metabolismo , Transplante Homólogo
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