Sucralfate enemas reduce the oxidative tissue damage and preserves the contents of E-cadherin and Β-catenin in colonic mucosa without fecal stream

ABSTRACT Purpose: To evaluate the effects of sucralfate enemas in tissue contents of E-cadherin and ?-catenin in an experimental diversion colitis. Methods: Thirty-six male Wistar rats were submitted to a proximal colostomy and a distal mucous fistula. They were allocated into three groups: first group received daily saline enemas (2 mL/day) and the two other groups daily enemas with sucralfate at dosage of 1 or 2 g/kg/day, respectively. Six animals of each group were euthanized after two weeks and six animals after four weeks. The inflammation of the excluded mucosa was evaluated by histological analysis. The oxidative damage was quantified by measurement of malondialdehyde tissue levels. The expression of E-cadherin and ?-catenin was identified by immunohistochemistry, and its contents were quantified by computer-assisted image analysis. Results: Sucralfate enemas reduced inflammation in animals subjected to treatment with 2 g/kg/day by four weeks, and the levels of oxidative damage in mucosa without fecal stream irrespective of concentration and time of intervention. E-cadherin and ?-catenin content increased in segments without fecal stream in those animals subjected to treatment with sucralfate. Conclusions: Sucralfate reduces the inflammation and oxidative stress and increases the tissue content of E-cadherin and ?-catenin in colonic mucosa devoid to the fecal stream.

Role of p120 in mechanical stretch-induced transferring of E-cadherin to cytoplasm in mouse alveolar epithelial cells / 中华麻醉学杂志

Objective To evaluate the role of pl20-catenin protein (p120) in mechanical stretchinduced transferring of E-cadherin to cytoplasm in mouse alveolar epithelial cells.Methods Experiment Ⅰ Mouse alveolar epithelial cells (MLE-12 cells) were seeded in 6-well cell stretch plates at a density of (1.0-1.5) ×106 cells/well and divided into 3 groups (n=12 each) using a random number table:control group (group C),cyclic stretch for 2 h group (group CS2) and cyclic stretch for 4 h group (group CS4).The cells underwent 20％ cyclic stretch at 0.5 Hz (stretch:intermittence =1 ∶ 1) for 2 and 4 h in CS2 and CS4 groups,respectively.The cells underwent no cyclic stretch in group C.The expression of p120,E-cadherin and phosphorylated Src kinase (p-Src) and expression of E-cadherin in cytomembrane and cytoplasma were detected by Western blot.Experiment Ⅱ MLE-12 cells were seeded in 6-well cell stretch plates at a density of (1.0-1.5)× 106 cells/well and divided into 4 groups (n =6 each) using a random number table:control group (group C),cyclic stretch group (group CS),p120 small interfering RNA (siRNA) transfection group (group p120 siRNA),and p120 siRNA transfection plus cyclic stretch group (group p120 siRNA+CS).The cells were transfected with scramble siRNA in C and CS groups,and 24 h later the cells underwent 20％ cyclic stretch for 2 h at 0.5 Hz (stretch:intermittence =1 ∶ 1) in group CS.The cells were transfected with p120 siRNA in p120 siRNA and p120 siRNA+CS groups,and 24 h later the cells underwent 20％ cyclic stretch for 2 h at 0.5 Hz (stretch ∶ intermittence =1 ∶ 1) in group p120 siRNA+CS.The expression of E-cadherin in cytomembrane and cytoplasm was detected by Western blot after the end of treatment in each group.Results Experiment Ⅰ Compared with group C,the expression of p120 and E-cadherin was significantly down-regulated,the expression of p-Src was up-regulated,the expression of E-cadherin in cytomembrane was down-regulated,and the expression of E-cadherin in cytoplasm was up-regulated in CS2 and CS4 groups (P ＜ 0.05).Compared with group CS2,the expression of p120 and E-cadherin was significantly down-regulated,the expression of p-Src was up-regulated,the expression of E-cadherin in cytomembrane was down-regulated,and the expression of E-cadherin in cytoplasm was upregulated in group CS4 (P ＜ O.05).Experiment Ⅱ Compared with group C,the expression of E-cadherin in cytomembrane was significantly down-regulated,and the expression of E-cadherin in cytoplasm was up-regulated in CS,p120 siRNA and p120 siRNA+CS groups (P＜ 0.05).Compared with group CS or group p120 siRNA,the expression of E-cadherin in cytomembrane was significantly down-regulated,and the expression of E-cadherin in cytoplasm was up-regulated in group p120 siRNA+CS (P＜0.05).Conclusion The degradation of p120 can promote mechanical stretch-induced transferring of E-cadherin to cytoplasm in mouse alveolar epithelial cells.

Oxidative stress and changes in the content and pattern of tissue expression of ß-catenin protein in diversion colitis

OBJECTIVE: The aim of this study is to verify if oxidative stress is related to changes in content and pattern of β-catenin protein expression in an experimental model of diversion colitis. METHODS: Sixty Wistar rats were submitted to intestinal bypass. The animals were divided into three groups according to the sacrifice to take place in six, 12 and 18 weeks. For each group, five animals only underwent laparotomy (control). The presence of colitis was diagnosed by histological study, and its severity, by inflammation grading scale. Cellular oxidative stress was measured by comet assay. Tissue expression of β-catenin protein was analyzed by the immunohistochemistry and quantification of its tissue content by computerized morphometry. Statistical analysis was performed with the Student's t-test, median, Mann-Whitney, ANOVA and Kruskal-Wallis, adopting a significance level of 5% (p <0.05). RESULTS: Colon segments without fecal stream developed colitis, which worsened with time of exclusion. Segments without fecal stream suffer higher levels of oxidative stress when compared to those with stream, and it worsens with time of exclusion. The levels of cellular oxidative stress are directly related to the degree of inflammation. The total content of ß-catenin in segments without fecal stream reduces after six weeks, and does not vary thereafter. The content of β-catenin in the apical portion of the colon crypts decreases with time, whereas in the basal region, it increases. The total content of ß-catenin is inversely related to the degree of inflammation and levels of tissue oxidative stress levels. CONCLUSION: There are changes in tissue content of E-cadherin and increased expression of ß-catenin in proliferative regions of colonic crypts, related with oxidative tissue stress. (AU)

OBJETIVO: O objetivo do presente estudo é avaliar a relação entre estresse oxidativo e conteúdo tecidual de β-catenina em modelo experimental de colite de exclusão. MÉTODOS: Sessenta ratos Wistar foram submetidos à derivação intestinal e divididos em três grupos experimentais segundo o sacrifício ser realizado em 6, 12 e 18 semanas. Para cada grupo, cinco animais foram submetidos apenas a laparotomia (controle). A colite foi diagnosticada por estudo histológico, enquanto sua intensidade por escala de graduação inflamatória. Os níveis de estresse oxidativo foram mensurados pelo ensaio cometa, enquanto a expressão e o conteúdo tecidual de ß-catenina por imunoistoquímica e morfometria computadorizada, respectivamente. Os resultados foram analisados pelos testes t de Student, Mann Whitney, ANOVA e Kruskal-Wallis, estabelecendo-se nível de significância de 5% (p<0,05). RESULTADOS: Nos segmentos sem trânsito fecal ocorre desenvolvimento de colite que piora com o tempo de exclusão. Segmentos sem trânsito sofrem maiores níveis de estresse oxidativo quando comparados àqueles com trânsito, piorando com o tempo de exclusão. Os níveis de estresse oxidativo encontram-se diretamente relacionados a piora da inflamação. O conteúdo total de ß-catenina no cólon sem trânsito reduz após seis semanas de exclusão. O conteúdo de ß-catenina no ápice das criptas cólicas diminui com o tempo, enquanto na região basal, aumenta. O conteúdo total da β-catenina encontra-se inversamente relacionado ao grau de inflamação e aos níveis de estresse oxidativo. CONCLUSÃO: Existe redução no conteúdo de ß-catenina, principalmente no ápice das glândulas cólicas e aumento nas regiões basais, relacionadas à piora do estresse oxidativo. (AU)

Cx43, ZO-1, alpha-catenin and beta-catenin in cataractous lens epithelial cells.

Specimens of the anterior lens capsule with an attached monolayer of lens epithelial cells (LECs) were obtained from patients (n052) undergoing cataract surgery. Specimens were divided into three groups based on the type of cataract: nuclear cataract, cortical cataract and posterior subcapsular cataract (PSC). Clear lenses (n011) obtained from donor eyes were used as controls. Expression was studied by immunofluorescence, real-time PCR and Western blot. Statistical analysis was done using the student’s t-test. Immunofluorescence results showed punctate localization of Cx43 at the cell boundaries in controls, nuclear cataract and PSC groups. In the cortical cataract group, cytoplasmic pools of Cx43 without any localization at the cell boundaries were observed. Real-time PCR results showed significant up-regulation of Cx43 in nuclear and cortical cataract groups. Western blot results revealed significant increase in protein levels of Cx43 and significant decrease of ZO-1 in all three cataract groups. Protein levels of alpha-catenin were decreased significantly in nuclear and cortical cataract group. There was no significant change in expression of beta-catenin in the cataractous groups. Our findings suggest that ZO-1 and alpha-catenin are important for gap junctions containing Cx43 in the LECs. Alterations in cell junction proteins may play a role during formation of different types of cataract.

Advances in vascular endothelial cadherin / 国际脑血管病杂志

Vascular endothelial cadherin (VE-cadherin) is a transmembrane adhesion protein of specific expression on vascular endothelial cell surface. It mediates the adhesion between adjacent endothelial cells. It plays important roles in maintaining vascular integrity, regulating permeability between endothelial cells, leukocyte extravasation, and intracellular signal transduction. In addition to its adhesion properties, VE-cadherin also participants in regulating various intracellular processes, such as cell proliferation, apoptosis as well as modulating the function of vascular endothelial growth factor receptor. Consequently, VE-cadherin is essential for angiogenesis and postnatal neovascularization during embryogenesis. It plays important roles by participating in angiogenesis in the processes of atherosclerosis of various aspects.

Análise da expressão de moléculas de adesão no tumor primário e em metástases ósseas e linfonodais de pacientes com câncer de próstata / Adhesion molecules in localized prostate cancer and in bone and lymph node metastases

Objetivo: As moléculas de adesão celular (MAC) são essenciais para a manutenção do fenótipo epitelial. Alguns estudos têm relatado associação entre as alterações de sua expressão e a carcinogênese, mas o seu papel no câncer de próstata não é claro. Nosso objetivo foi estudar o perfil de expressão de E-caderina, cateninas e integrinas em espécimes cirúrgicos de câncer de próstata e associar as suas expressões com a evolução do tumor. Avaliamos também o perfil de expressão em metástases ósseas e linfonodais, a fim de compreender a influência destes marcadores na progressão do câncer de próstata. Materiais e Métodos: Foram selecionados 111 pacientes com câncer de próstata localizado tratados com prostatectomia radical pelo mesmo cirurgião. Sessenta pacientes não apresentaram recidiva tumoral após acompanhamento médio de 123 meses. A expressão das MAC foi avaliada por imuno-histoquímica (IH) em microarranjo tecidual (TMA), contendo duas amostras de cada tumor. Empregamos análise semiquantitativa para avaliação da expressão e determinamos a associação entre a expressão de cada MAC com a recorrência do tumor após a cirurgia. Avaliamos também a expressão das MAC por IH em TMA contendo espécimes de 28 metástases ósseas e em outro TMA contendo 19 metástases linfonodais com seus 19 tumores primários correspondentes. Resultados: Nos tumores primários a análise multivariada mostrou que a expressão das integrinas 3 e 3 1 relaciona-se com recidiva da doença. Quando a expressão de 3 foi forte e a expressão de 3 1 foi positiva, as chances de recorrência foram de 3,0 e 2,5 vezes maior. Apenas 19% e 28% dos pacientes estavam livres de recidiva após seguimento médio de 123 meses, quando os tumores apresentavam forte imunoexpressão de 3 ou positiva para 3 1 respectivamente. Outras integrinas apresentaram expressão reduzida, exceto 6 que foi expressa pela maioria dos tumores primário e metástases. A E-Caderina e as cateninas não mostraram associação com o prognóstico no tumor...

Purpose: Cell adhesion molecules (CAM) are essential for the maintenance of epithelial phenotype. Some studies have reported correlations between abnormalities in their expression and carcinogenesis, but their role in prostate cancer is unclear. Our aim was to study the expression profile of E-cadherin, catenins and integrins in surgical specimens of prostate cancer and associate their expression with outcome. We also assessed these expressions in bone and lymph node metastases in order to understand their influence in the progression of prostate cancer. Materials and Methods: We selected 111 patients with localized prostate cancer who underwent radical prostatectomy performed by the same surgeon. Sixty patients had no tumor recurrence after a median follow-up of 123 months. The CAM expression was evaluated by immunohistochemistry in a tissue microarray (TMA) containing two samples of each tumor. A semiquantitative analysis was employed and we measured the association between the expression of CAM and tumor recurrence. We also evaluated CAM expression by immunohistochemistry in a TMA containing 28 bone metastases and in other TMA containing 19 lymph node metastases with their corresponding 19 primary tumors. Results: In primary tumors, multivariate analysis showed that expression of 3 and 31 integrins was related to worse outcome. When 3 expression was strong and 31 expression was positive,the odds of recurrence were 3.0 and 2.5 fold higher. Only 19% and 28% of patients were recurrence-free in a mean follow up period of 123 months, when tumors showed strong 3 or positive 31 immuno-expression respectively. Other integrins have shown reduced expression, except 6 , which was expressed in most primary and metastatic cases. E-cadherin and catenins expressions were not associated with primary tumor outcome. At the metastatic setting, there was a global loss of CAM expression. We observed reliable gain of expression with prostate cancer progression...

Expression of cell adhesion molecules in the normal and T3 blocked development of the tadpole's kidney of Bufo arenarum (Amphibian, Anuran, Bufonidae) / Expressão das moléculas de adesão celular no desenvolvimento normal e com a inibição do hormônio tireoidea do rim nas larvas do Bufo arenarum (Amphibia, Anura, Bufonidae)

Cell adhesion molecules act as signal transducers from the extracellular environment to the cytoskeleton and the nucleus and consequently induce changes in the expression pattern of structural proteins. In this study, we showed the effect of thyroid hormone (TH) inhibition and arrest of metamorphosis on the expression of E-cadherin, β-and α-catenin in the developing kidney of Bufo arenarum. Cell adhesion molecules have selective temporal and spatial expression during development suggesting a specific role in nephrogenesis. In order to study mechanisms controlling the expression of adhesion molecules during renal development, we blocked the B. arenarum metamorphosis with a goitrogenic substance that blocks TH synthesis. E-cadherin expression in the proximal tubules is independent of thyroid control. However, the blockage of TH synthesis causes up-regulation of E-cadherin in the collecting ducts, the distal tubules and the glomeruli. The expression of β-and α-catenin in the collecting ducts, the distal tubules, the glomeruli and the mesonephric mesenchyme is independent of TH. TH blockage causes up-regulation of β-and α-catenin in the proximal tubules. In contrast to E-cadherin, the expression of the desmosomal cadherin desmoglein 1 (Dsg-1) is absent in the control of the larvae kidney during metamorphosis and is expressed in some interstitial cells in the KClO4 treated larvae. According to this work, the Dsg-1 expression is down-regulated by TH. We demonstrated that the expression of E-cadherin, Dsg-1, β-catenin and α-catenin are differentially affected by TH levels, suggesting a hormone-dependent role of these proteins in the B. arenarum renal metamorphosis.

Moléculas de adesão celular atuam como tradutores do ambiente extracelular para o citoesqueleto e o núcleo e, conseqüentemente, induzindo mudanças no padrão da expressão das proteínas estruturais. Neste estudo, observamos os efeitos da inibição do hormônio tireóidea (TH) e detenção da metamorfose na expressão da E-caderina, β- e α- catenina no desenvolvimento do rim do Bufo arenarum. As moléculas de adesão celular durante o desenvolvimento têm uma expressão temporal e espacial seletiva, sugerindo um papel específico na nefrogênese. Com o propósito de estudar os mecanismos de controle da expressão das moléculas de adesão durante o desenvolvimento renal, bloqueou-se a metamorfose do B. arenarum com uma substancia goitrogênica que bloqueia a síntese de TH. A expressão da E-caderina nos tubos proximais é independente do controle da tireóide. Entretanto, o bloqueio da síntese de TH provoca uma sobre elevação da E-caderina nos dutos coletores, nos tubos distais e nos glomérulos. A expressão da β- e α-catenina nos dutos coletores, nos tubos distais, nos glomérulos e no mesênquima mesonéfrico é independente da TH. O bloqueio da TH causa uma sobre-regulação da β- e α-catenina nos tubos proximais. Em contraste com a E-caderina, a expressão da caderina desmossomal demogloína 1 (Dsg-1) é ausente no controle durante a metamorfose da fase larval dos rins e se expressa em algumas células intersticiais nas larvas tratadas com KClO4. De acordo com este trabalho, a expressão Dsg-1 é subregulada pela TH. Demonstramos que a expressão da E-caderina, Dsg-1, β-catenina e α-catenina são afetadas de forma diferencial pelos níveis de TH, sugerindo um dependência hormonal destas proteínas na metamorfose renal do B. arenarum.

Expression of E-cadherin and ?/? Catenins and their Relationship with the Invasiveness of Pituitary Adenoma / 医学研究杂志

Objective To explore the relationship between the expression of E-cadherin catenin complex(CCC) and the invasiveness of pituitary adenoma.Methods The expession of E-cadherin catenin complex was determined by immunohistochemistry in 45 cases of human pituitary adenomas by random sampling,including invasive adenoma 27 cases,noninvasive adenoma 18 cases.The relativity of their expression with hormone-producing,pituitary apoplexy and necrosis or cystoid change,tumor diameter was analyzed.Results The invasive group had a significantly lower expression of E-cad and ?-cat than that of noninvasive group(?2=8.551,P0.05).Moreover,the expression of E-cad was significantly lower in endocrine inactive group than that in endocrine active group(?2 =5.020,P

Expression of catenins and cyclin D1 in poorly differentiated squamous cell carcinoma of nasopharynx and their potentially clinical significance / 中国癌症杂志

Background and purpose:Studies have shown that some molecular markers could serve as prognostic factors for nasopharynx carcinoma, but the predictive role of catenins and cyclin D1 remains uncertain for the disease. Our paper is to investigate the expression of catenins(?-,?- and ?-) and cyclin D1 in nasopharyngeal carcinoma as well as to analysis their relation to clinic factors and prognosis. Methods:We retrieved 38 paraffin-embedded specimens of nasopharynx carcinoma, immunohistochemistry was used to examine the expression of ?-,?- and ?-catenin , cyclin D1 and tumor proliferation activity marker ki-67.Results:Reduced expression of ?-,?- ,?-catenin and cyclin D1 was observed in most of the tumors. Our preliminary study demonstrated that there was no significant correlation between their expression with T-stage, N-stage, clinical stage and primary tumor volume, as well as with ki-67 stain. In unviarance analysis, patients with reduced expression of ?-catenin had poorer prognosis than those with high expression, 5 year overall survival and disease free survival rates of these two groups were 53.2%, 29.0% and 81.9%, 76.0%, respectively(P

Expression of Glutathione S-Transferase, E-Cadherin, and Catenins during N,N-Diethylnitrosamine-Induced Hepatocarcinogenesis in Rat Liver

N,N-Diethylnitrosamine (DEN) has been proved to have carcinogenic potential in the initiation or promotion stage and the transformed cells proliferate to form preneoplastic nodules which are positive for placental form of glutathione S-transferase (GST-P). E-Cadherin, a member of the cadherin family, is expressed in epithelial cells. To evaluate the role of adhesion molecules (E-Cadherin, alpha-catenin, and beta-catenin), which have not been well understood in carcinogenesis, we investigated the changes of E-cadherin, alpha-Catenin and beta-Catenins by immunohistochemistry and immunoblotting in DEN-induced hepatocarcinogenesis of rat liver. In addition, the sequential analysis of histopathology and the expression of GST-P were also examined. Immunoreactive areas for GST-P were gradually increased from early period of carcinogenesis and strong GST-P positive foci were noted in various lesions, especially in the clear cell and eosinophilic cell nodules. Immunohistochemically, the E-Cadherin expression was increased in DEN-treated preneoplastic nodules in 4 and 10 weeks and hepatocellular carcinomas displayed relatively reduced expression compared with the hyperplastic nodules. But alpha- and beta-catenin expression was increased in hyperplastic nodules and hepatocellular carcinomas. Immunoblotting studies revealed that the level of alpha-catenin (cytosol and membranous fraction) was overexpressed in hyperplastic nodules as well as hepatocellular carcinomas, which showed markedly increased expression. The membranous fraction of beta-catenin was markedly increased in 10 weeks of DEN treatment and slightly reduced in hepatocellular carcinomas. These findings suggest that during DEN-induced hepatocarcinogenesis, the clear cell and eosinophilic cell nodules expressing GST-P in their cytoplasm are early transformed cell nodules. The altered expression of E-Cadherin and catenins is closely related with tumor propagation. Loss or reduced expression of E-cadherin may play a role in the progression of late hyperplastic nodule to hepatocellular carcinoma in DEN-induced rat hepato carcinogenesis.

EXPRESSION OF E-CADHERIN/CATENIN COMPLEX ON HUMAN NON-SMALL CELL LUNG CARCINOMA CELL LINES / 解剖学报

Objective To investigate the involvement of the E-cadherin-catenin adhesion system in the progression of human non-small cell lung carcinoma cell lines. Methods Expression of E-cadherin, alpha-catenin, and beta-catenin in seven human lung carcinoma cell lines were studied with immunocytochemistry and RT-PCR. Results Abnormal expression of at least one component of the E-cadherin/catenin complex was seen in each non-small cell lung carcinoma cell line.Conclusion The abnormal expression of E-cadherin, alpha-catenin, and beta-catenin was closely related with the occurrence of lung carcinomas.