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1.
Oncogene ; 39(22): 4331-4343, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32313225

RESUMO

Breast cancer is the second leading cause of cancer-related deaths among women, largely due to the progression of a significant fraction of primary tumours to the metastatic stage. Here, we show that zinc-finger protein 750 (ZNF750) opposes the migration and invasion of breast cancer cells by repressing a prometastatic transcriptional programme, which includes genes involved in focal adhesion and extracellular matrix interactions, such as LAMB3 and CTNNAL1. Mechanistically, ZNF750 recruits the epigenetic modifiers KDM1A and HDAC1 to the promoter regions of LAMB3 and CTNNAL1, influencing histone marks and transactivating these genomic sites. Gene expression analysis in cancer patient datasets indicated that ZNF750 and its targets were negative prognostic factors in breast cancer. Together, our findings shed light on the molecular mechanism by which ZNF750 regulates cell migration and invasion, suggesting a role in breast cancer metastasis.


Assuntos
Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Código das Histonas , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Proteínas de Neoplasias/fisiologia , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/fisiologia , Sítios de Ligação , Neoplasias da Mama/genética , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Polaridade Celular , Conjuntos de Dados como Assunto , Feminino , Adesões Focais/genética , Complexo de Golgi/ultraestrutura , Histona Desacetilase 1/metabolismo , Histona Desmetilases/metabolismo , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Prognóstico , Mapeamento de Interação de Proteínas , Ativação Transcricional , Proteínas Supressoras de Tumor , Via de Sinalização Wnt/genética , alfa Catenina/biossíntese , alfa Catenina/genética , Calinina
2.
J Allergy Clin Immunol ; 141(3): 991-1001, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29030101

RESUMO

BACKGROUND: Peanut allergy (PA) is a complex disease with both environmental and genetic risk factors. Previously, PA loci were identified in filaggrin (FLG) and HLA in candidate gene studies, and loci in HLA were identified in a genome-wide association study and meta-analysis. OBJECTIVE: We sought to investigate genetic susceptibility to PA. METHODS: Eight hundred fifty cases and 926 hyper-control subjects and more than 7.8 million genotyped and imputed single nucleotide polymorphisms (SNPs) were analyzed in a genome-wide association study to identify susceptibility variants for PA in the Canadian population. A meta-analysis of 2 phenotypes (PA and food allergy) was conducted by using 7 studies from the Canadian, American (n = 2), Australian, German, and Dutch (n = 2) populations. RESULTS: An SNP near integrin α6 (ITGA6) reached genome-wide significance with PA (P = 1.80 × 10-8), whereas SNPs associated with Src kinase-associated phosphoprotein 1 (SKAP1), matrix metallopeptidase 12 (MMP12)/MMP13, catenin α3 (CTNNA3), rho GTPase-activating protein 24 (ARHGAP24), angiopoietin 4 (ANGPT4), chromosome 11 open reading frame (C11orf30/EMSY), and exocyst complex component 4 (EXOC4) reached a threshold suggestive of association (P ≤ 1.49 × 10-6). In the meta-analysis of PA, loci in or near ITGA6, ANGPT4, MMP12/MMP13, C11orf30, and EXOC4 were significant (P ≤ 1.49 × 10-6). When a phenotype of any food allergy was used for meta-analysis, the C11orf30 locus reached genome-wide significance (P = 7.50 × 10-11), whereas SNPs associated with ITGA6, ANGPT4, MMP12/MMP13, and EXOC4 and additional C11orf30 SNPs were suggestive (P ≤ 1.49 × 10-6). Functional annotation indicated that SKAP1 regulates expression of CBX1, which colocalizes with the EMSY protein coded by C11orf30. CONCLUSION: This study identifies multiple novel loci as risk factors for PA and food allergy and establishes C11orf30 as a risk locus for both PA and food allergy. Multiple genes (C11orf30/EMSY, SKAP1, and CTNNA3) identified by this study are involved in epigenetic regulation of gene expression.


Assuntos
Epigênese Genética , Loci Gênicos , Estudo de Associação Genômica Ampla , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Hipersensibilidade a Amendoim/genética , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/genética , Homólogo 5 da Proteína Cromobox , Feminino , Proteínas Filagrinas , Humanos , Masculino , Hipersensibilidade a Amendoim/epidemiologia , Hipersensibilidade a Amendoim/metabolismo , Fosfoproteínas/biossíntese , Fosfoproteínas/genética , Fatores de Risco , alfa Catenina/biossíntese , alfa Catenina/genética
3.
Anticancer Res ; 35(6): 3361-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26026096

RESUMO

BACKGROUND: Abnormal catenin expression has been related to mammary carcinogenesis in both human and canine species and they are considered tumor- and invasion-suppressor molecules; however, in feline mammary tissues they have been scarcely studied. MATERIALS AND METHODS: The immunohistochemical expression of α-, ß- and p120-catenin was studied in a series of normal feline mammary glands, hyperplastic/dysplastic lesions and benign and malignant mammary tumors. Their relationship with clinicopathological parameters and with E- and P-cadherin expression was assessed. RESULTS: Normal tissues, hyperplastic/dysplastic lesions and benign tumors expressed α-, ß- and p120-catenin in the membrane of more than 75% of the luminal epithelial cells, while in malignant tumors, there was a reduction in their membranous expression and a p120-catenin cytoplasmic expression in 40%. Reduced α-catenin expression was related to tumor features with prognostic value, namely tumor size (p=0.0203) and necrosis (p=0.0205). The expression of α-, ß- and p120-catenin were individually related to each other and collectively associated with E-cadherin expression. CONCLUSION: The results demonstrate a relationship between feline mammary carcinogenesis and decreased expression of catenins, suggesting that they may represent a valuable tool in the diagnosis of feline mammary neoplasms.


Assuntos
Neoplasias da Mama/genética , Caderinas/biossíntese , Cateninas/biossíntese , alfa Catenina/biossíntese , beta Catenina/biossíntese , Animais , Biomarcadores Tumorais/biossíntese , Neoplasias da Mama/patologia , Neoplasias da Mama/veterinária , Carcinogênese/genética , Gatos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , delta Catenina
4.
Mol Biol Cell ; 25(3): 347-55, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24307680

RESUMO

Myc interacting zinc finger protein-1 (Miz1) is a transcription factor known to regulate cell cycle- and cell adhesion-related genes in cancer. Here we show that Miz1 also plays a critical role in neural crest development. In the chick, Miz1 is expressed throughout the neural plate and closing neural tube. Its morpholino-mediated knockdown affects neural crest precursor survival, leading to reduction of neural plate border and neural crest specifier genes Msx-1, Pax7, FoxD3, and Sox10. Of interest, Miz1 loss also causes marked reduction of adhesion molecules (N-cadherin, cadherin6B, and α1-catenin) with a concomitant increase of E-cadherin in the neural folds, likely leading to delayed and decreased neural crest emigration. Conversely, Miz1 overexpression results in up-regulation of cadherin6B and FoxD3 expression in the neural folds/neural tube, leading to premature neural crest emigration and increased number of migratory crest cells. Although Miz1 loss effects cell survival and proliferation throughout the neural plate, the neural progenitor marker Sox2 was unaffected, suggesting a neural crest-selective effect. The results suggest that Miz1 is important not only for survival of neural crest precursors, but also for maintenance of integrity of the neural folds and tube, via correct formation of the apical adhesion complex therein.


Assuntos
Fatores de Transcrição Kruppel-Like/genética , Sistema Nervoso/embriologia , Crista Neural/embriologia , Tubo Neural/embriologia , Neurogênese/genética , Animais , Proteínas Aviárias/biossíntese , Proteínas Aviárias/genética , Caderinas/biossíntese , Adesão Celular , Movimento Celular , Proliferação de Células , Sobrevivência Celular/genética , Embrião de Galinha , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Fatores de Transcrição Kruppel-Like/biossíntese , Fator de Transcrição MSX1/genética , Morfolinos/genética , Placa Neural/embriologia , Fator de Transcrição PAX7/genética , Fatores de Transcrição SOXB1 , Fatores de Transcrição SOXE/genética , alfa Catenina/biossíntese
5.
Anticancer Res ; 32(12): 5245-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23225423

RESUMO

AIM: To determine whether modulation of expression of cell adhesion molecules occurs in neoplastic transformation of laryngeal epithelium and to investigate their possible role in clinical outcome. MATERIALS AND METHODS: Fifty-five T1 N0 laryngeal biopsies were tested by immunohistochemistry for the E-cadherin/α-catenin adhesion complex. RESULTS: High immunohistochemical expression of E-cadherin and α-catenin was found in 18% and 53% cases, respectively. Expression of both adhesion molecules decreased according to histological grading; a significant relationship was particularly found between high E-cadherin expression and G1 cases (p=0.013). High E-cad-herin expression was statistically associated with in situ carcinoma (p=0.006). Non-statistical significance was evidenced between these adhesion molecules and tobacco use or site of occurence. Regarding clinical outcome, recurrence was associated with low expression of both adhesion molecules. CONCLUSION: E-cadherin and α-catenin down-regulation might be associated with neoplastic transformation in laryngeal tissues and might be regarded as a risk factor for clinical recurrence.


Assuntos
Caderinas/biossíntese , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , alfa Catenina/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Biópsia , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Distribuição Tecidual
6.
Histopathology ; 61(4): 667-74, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22571452

RESUMO

AIMS: Phyllodes tumours (PT) are rare but clinically important fibroepithelial tumours of the breast. ß-Catenin, a key component in Wnt signalling, has been shown to be important in the development of PT. It also functions as a component of the cadherin complex, which may therefore be implicated in PT pathogenesis. By assessing stromal α-catenin, ß-catenin and E-cadherin expression in 158 PT cases using immunohistochemistry and examining associations with clinicopathological features, we aimed to determine the role of these proteins in PT pathogenesis. METHODS AND RESULTS: Cytoplasmic ß-catenin correlated with α-catenin expression. A significantly higher expression of both markers was observed in borderline than in benign PT (P = 0.003 and <0.001, respectively), but a lower level was found in malignant PT. Cytoplasmic E-cadherin expression was significantly higher in borderline and malignant than in benign PT (P = 0.001 and 0.012, respectively), but was not correlated with other markers. Both E-cadherin and α-catenin showed stronger correlations with histological parameters than ß-catenin. α-Catenin showed a significant correlation with recurrence (P = 0.005 and 0.016, respectively). CONCLUSION: α- and ß-catenins may be important in the early stages of PT development, while E-cadherin may be required for malignant development. The correlation of α-catenin expression with tumour recurrence may be relevant in predicting PT behaviour.


Assuntos
Neoplasias da Mama/patologia , Caderinas/biossíntese , Tumor Filoide/patologia , alfa Catenina/biossíntese , beta Catenina/biossíntese , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Tumor Filoide/metabolismo , Prognóstico
7.
PLoS One ; 6(9): e24967, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21966391

RESUMO

The aim of this study was to characterize the oncogenic function and mechanism of Cathepsin Z (CTSZ) at 20q13.3, a frequently amplified region in hepatocellular carcinoma (HCC). Real-time PCR were used to compare CTSZ expression between paired HCC tumor and non-tumor specimens. CTSZ gene was stably transfected into HCC line QGY-7703 cells and its role in tumorigenicity and cell motility was characterized by soft agar, wound-healing, transwell invasion and cell adhesion assay, and tumor xenograft mouse model. Western blot analysis was used to study expression of proteins associated with epithelial-mesenchymal transition (EMT).Upregulation of CTSZ was detected in 59/137 (43%) of primary HCCs, which was significantly associated with advanced clinical stage (P = 0.000). Functional study found that CTSZ could increase colony formation in soft agar and promote cell motility. Further study found that the metastatic effect of CTSZ was associated with its role in inducing epithelial-mesenchymal transition (EMT) by upregulating mesenchymal markers (fibronectin and vimentin) and downregulating epithelial markers (E-cadherin and α-catenin). In addition, CTSZ could also upregulate proteins associated with extracellular matrix remodeling such as MMP2, MMP3 and MMP9. Taken together, our data suggested that CTSZ was a candidate oncogene within the 20q13 amplicon and it played an important role in HCC metastasis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Catepsina Z/biossíntese , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Ágar/química , Animais , Caderinas/biossíntese , Adesão Celular , Movimento Celular , Fibronectinas/biossíntese , Humanos , Masculino , Metaloproteinases da Matriz/biossíntese , Camundongos , Camundongos SCID , Metástase Neoplásica , Transplante de Neoplasias , Vimentina/biossíntese , Cicatrização , alfa Catenina/biossíntese
8.
Asian J Androl ; 13(3): 470-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21399649

RESUMO

The roles of E-cadherin and α-catenin were evaluated in the development of varicocele-induced infertility. Analysis of the association between the expression of E-cadherin/α-catenin and clinical/pathological parameters was performed. Thirty 10-week-old male rats (experimental group) were used for the experiments; the left renal vein was ligated to form a varicocele. The abdomen was incised in 30 rats (control group) and no procedure was performed on 10 rats (baseline group). The weights of the left testis, serum reactive oxygen species (ROS), testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and degenerative changes in the seminiferous tubules after 4 and 8 weeks were recorded. The expression of E-cadherin and α-catenin was evaluated by immunohistochemical (IHC) staining and Western blot analysis. The ROS increased in the 8-week experimental group, compared with the baseline and control groups (P < 0.001 for both). Additionally, FSH significantly increased in the 4- and 8-week experimental group compared with the control groups (P = 0.013 and P = 0.032, respectively). The ratio of degenerative changes in the seminiferous tubules of the experimental groups increased. The IHC staining showed that the expression of E-cadherin and α-catenin decreased in the 4- and 8-week experimental groups. Similar to the IHC staining, the experimental group had decreased reactivity on Western blot analysis. The expression of E-cadherin and α-catenin was significantly associated with the ROS and degenerative changes in the seminiferous tubules. The results of this study suggest that damage to the blood-testis barrier (BTB) is associated with varicocele-induced male infertility, and that ROS may cause damage to the BTB.


Assuntos
Caderinas/biossíntese , Infertilidade Masculina/etiologia , alfa Catenina/biossíntese , Animais , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/patologia , Infertilidade Masculina/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Túbulos Seminíferos/patologia , Varicocele/complicações
9.
Anticancer Res ; 30(12): 4993-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21187480

RESUMO

UNLABELLED: The aim of this study was to determine whether modulation of expression of cell adhesion molecules may occur in neoplastic transformation of endometrial epithelium. MATERIALS AND METHODS: E-Cadherin and α-catenin protein expression were evaluated by immunohistochemistry in 124 biopsies representative of normal, hyperplastic and neoplastic endometrium. RESULTS: In normal endometrium (proliferative, secretive and atrophic endometrium) strong homogeneous, E-cadherin and α-catenin reactivity was found; 58.3% and 66.6% of biopsies representative of simple hyperplastic endometrium were homogeneously positive for E-cadherin and α-catenin, respectively, whereas no samples representative of atypical hyperplasia showed evidence of homogeneous E-cadherin or α-catenin expression. No expression of homogeneous E-cadherin was seen in endometrial adenocarcinomas; α-catenin homogeneous immunostaining was observed in 2 G1 and 2 G2 out of 22 adenocarcinoma samples (18.2%). A homogeneous co-expression of both molecules was seen only in normal (70%) and simple hyperplastic (46%) endometrium. CONCLUSION: These results suggest that E-cadherin and α-catenin down-regulation might be associated with neoplastic transformation of endometrial tissues.


Assuntos
Caderinas/biossíntese , Hiperplasia Endometrial/metabolismo , Neoplasias do Endométrio/metabolismo , alfa Catenina/biossíntese , Adenocarcinoma/metabolismo , Caderinas/metabolismo , Endométrio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Prognóstico , Distribuição Tecidual , alfa Catenina/metabolismo
10.
Leuk Res ; 34(12): 1551-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20573398

RESUMO

Most patients with myelodysplastic syndrome (MDS) are classified at diagnosis as having a low/INT-I or INT-II/high risk disease, based on the classical International Prognostic Scoring System (IPSS) criteria. The low/INT-I risk patients are usually managed mildly with supportive care, including red blood cell (RBC) transfusions, erythroid stimulating agents (ESAs), other cytokines (G-CSF, platelet stimulating agents), as well as thalidomide and lenalidomide. Some patients receive immunosuppressive therapy, and iron chelation is indicated in iron overloaded patients. Aggressive approach (hypomethylating agents, chemotherapy and stem cell transplantation) is usually not applied in such patients. Occasionally, we observe a "low risk" patient with rapid progression of disease and poor outcome. Can we identify demographic, clinical, laboratory, cellular-biological and/or molecular parameters that can predict "poor prognostic features" (PPF) in "low risk" MDS patients? Clinical and laboratory parameters have been reported to be associated with poor prognosis, in addition to the known "classical" IPSS criteria. These include older age, male gender, poor performance status, co-morbidities, degree of anemia, low absolute neutrophile count (ANC) and platelet counts, RBC transfusion requirements, high serum ferritin, high LDH, bone marrow (BM) fibrosis, increased number of BM CD34+ cells and multi-lineage dysplasia. Certain immunophenotypes (low CD11b, high HLA-Dr, CD34, CD13 and CD45), clonal granulocytes, multiple chromosomal abnormalities, chromosomal instability, short telomeres and high telomerase activity were also reported as PPF. Studies of apoptosis identified Bcl-2 expression and high caspase 3 as PPF, while the reports on survivin expression have been confusing. Recent exciting data suggest that methylation of p15 INK4b and of CTNNA1 (in 5q-), high level of methylation of other genes, absence of the TET2 mutation, down regulation of the lymphoid enhancer binding factor 1 (LEF1), mutation of the polycomb-associated gene ASXL1 and a specific 6-gene signature in gene expression profiling - are all associated with poor prognosis in MDS. Do we have data suggesting a different treatment for "low risk" MDS patients displaying PPF? Two teams, the combined Nordic-Italian and the GFM groups have reported an improved survival with ESAs. The GFM has achieved prolonged survival with iron chelation. Recently, encouraging data with survival advantage in azacitidine-treated patients have been published, including a few INT-I patients. Finally, data suggest that low/INT-I MDS patients who undergo stem cell transplantation (SCT0 do better than INT-II/high risk patients). In summary, some patients, classified as "low risk MDS" carry PPF. An appropriate therapeutic approach is indicated. Future updated classifications and prospective trials may lead to a better outcome.


Assuntos
Síndromes Mielodisplásicas , Fatores Etários , Antígenos de Diferenciação/sangue , Antineoplásicos/uso terapêutico , Caspase 3/biossíntese , Caspase 3/genética , Aberrações Cromossômicas , Inibidor de Quinase Dependente de Ciclina p15/biossíntese , Inibidor de Quinase Dependente de Ciclina p15/genética , Citocinas/uso terapêutico , Metilação de DNA/genética , Transfusão de Eritrócitos , Feminino , Ferritinas/sangue , Fibrose , Regulação da Expressão Gênica/genética , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Proteínas Inibidoras de Apoptose , Lenalidomida , Contagem de Leucócitos , Lipoproteínas LDL/sangue , Fator 1 de Ligação ao Facilitador Linfoide/biossíntese , Fator 1 de Ligação ao Facilitador Linfoide/genética , Masculino , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , Mutação , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/terapia , Contagem de Plaquetas , Prognóstico , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Receptores Proteína Tirosina Quinases/biossíntese , Receptores Proteína Tirosina Quinases/genética , Fatores de Risco , Fatores Sexuais , Survivina , Talidomida/análogos & derivados , Talidomida/uso terapêutico , alfa Catenina/biossíntese , alfa Catenina/genética , Receptor Tirosina Quinase Axl
11.
Breast Cancer Res Treat ; 122(1): 125-33, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19763817

RESUMO

Mutations of E-cadherin have been identified in half of lobular breast cancers and diffuse-type gastric cancers, two tumor subtypes with remarkably similar pathological appearances including small rounded cells with scant cytoplasm and a diffuse growth pattern. A causal role for E-cadherin gene mutations in the lobular breast cancer phenotype was recently demonstrated in E-cadherin knock-out mice. These observations suggested that another gene in the E-cadherin tumor suppressor pathway might be mutated in lobular breast cancers with wild-type E-cadherin genes. Here, we identified E-cadherin gene mutations exclusively in human breast cancer cell lines that grow with a rounded cell morphology. Using expression analyses and gene mutation analyses, we have identified four biallelic inactivating alpha-catenin mutations among 55 human breast cancer cell lines. All four alpha-catenin mutations predicted premature termination of the encoded proteins, and concordantly, none of the four mutant cell lines expressed alpha-catenin proteins. Importantly, three of the alpha-catenin mutant cell lines had the rounded cell morphology and all 14 cell lines with the rounded cell morphology had mutations of either E-cadherin or alpha-catenin. As anticipated, loss of alpha-catenin protein expression was associated with the lobular subtype in primary breast cancers. Together, our observations suggest that alpha-catenin may be a new tumor suppressor gene that operates in the E-cadherin tumor suppressor pathway.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Códon sem Sentido , Genes Supressores de Tumor , Proteínas de Neoplasias/genética , alfa Catenina/genética , Alelos , Neoplasias da Mama/genética , Caderinas/genética , Caderinas/fisiologia , Carcinoma/genética , Carcinoma Lobular/genética , Carcinoma Lobular/patologia , Adesão Celular/genética , Linhagem Celular Tumoral/metabolismo , Forma Celular/genética , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/deficiência , Análise de Sequência com Séries de Oligonucleotídeos , alfa Catenina/biossíntese , alfa Catenina/deficiência
12.
Biochem Biophys Res Commun ; 382(4): 745-50, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19324011

RESUMO

alpha- and beta-Catenin link cadherins to the actin-based cytoskeleton at adherens junctions and regulate cell-cell adhesion. Although roles of cadherins and canonical Wnt-/beta-catenin-signaling in osteoblastic differentiation have been extensively studied, the role of alpha-catenin is not known. Murine embryonic mesenchymal stem cells, C3H10T1/2 cells, were transduced with retrovirus encoding alpha-catenin (MSCV-alpha-catenin-HA-GFP). In the presence of Wnt-3A conditioned medium or osteogenic medium (beta-glycerol phosphate and ascorbic acid), cells overexpressing alpha-catenin showed enhanced osteoblastic differentiation as measured by alkaline phosphatase (ALP) staining and ALP activity assay compared to cells transduced with empty virus (MSCV-GFP). In addition, mRNA expression of osteocalcin and Runx2 was significantly increased compared to control. Cell aggregation assay revealed that alpha-catenin overexpression has significantly increased cell-cell aggregation. However, cellular beta-catenin levels (total, cytoplasmic-nuclear ratio) and beta-catenin-TCF/LEF transcriptional activity did not change by overexpression of alpha-catenin. Knock-down of alpha-catenin using siRNA decreased osteoblastic differentiation as measured by ALP assay. These results suggest that alpha-catenin overexpression increases osteoblastic differentiation by increasing cell-cell adhesion rather than Wnt-/beta-catenin-signaling.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/fisiologia , Osteoblastos/citologia , alfa Catenina/biossíntese , Animais , Adesão Celular , Diferenciação Celular/genética , Linhagem Celular , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteoblastos/metabolismo , RNA Interferente Pequeno/genética , Transcrição Gênica , alfa Catenina/genética , beta Catenina/metabolismo
13.
Neuroscience ; 161(2): 451-8, 2009 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-19328224

RESUMO

Trisomy of human chromosome 21 (Hsa 21) causes the pathological characteristics of Down syndrome (DS). Little is known about the mechanisms by which trisomy 21 affects the expression of genes on other chromosomes. Using a mouse model of DS, the Ts65Dn mouse, we have performed mRNA and protein measurements to identify genes on chromosomes not syntenic with Hsa 21 whose expression is affected by the presence of three copies of genes between loci Mrpl39 and Znf295 on mouse chromosome 16 (Mmu 16). We report the upregulation of beta-catenin, located on mouse chromosome 9 (Mmu 9) in Ts65Dn brain. Using immunocytochemistry on Ts65Dn and control mouse brain tissue, we observed a striking increase in beta-catenin expression specifically in the endothelial cells lining the cerebral blood vessels of the Ts65Dn mice. Since beta-catenin is involved in cell-cell adhesion, upregulation of this protein in DS may alter adherens protein interactions that are involved in the normal functions of endothelial cells. Elevated beta-catenin might be responsible for altered endothelial cell function/s leading to the impairment of brachial flow velocity observed in DS.


Assuntos
Encéfalo/metabolismo , Síndrome de Down/metabolismo , beta Catenina/biossíntese , Animais , Vasos Sanguíneos/metabolismo , Encéfalo/irrigação sanguínea , Caderinas/biossíntese , Córtex Cerebral/metabolismo , Cromossomos de Mamíferos/genética , Síndrome de Down/genética , Regulação para Baixo , Quinase 3 da Glicogênio Sintase/biossíntese , Glicogênio Sintase Quinase 3 beta , Imuno-Histoquímica , Camundongos , Camundongos Mutantes , Presenilina-1/biossíntese , RNA Mensageiro/biossíntese , Regulação para Cima , alfa Catenina/biossíntese , beta Catenina/genética
14.
Pathol Res Pract ; 205(5): 311-24, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19124205

RESUMO

The aims of this study were to analyze the cadherin/catenin adhesion complex in cells from abdominal and extra-abdominal aggressive fibromatosis tumors, and to estimate the correlation between the expression of the tested proteins and the clinical data of the desmoid patients. Immunohistochemistry was used to examine the expression of the cadherin/catenin adhesion complex: APC protein, alpha-, beta-catenin, and N-cadherin in archival material derived from 15 cases of extra-abdominal desmoid tumor (E-AD) and 20 cases of abdominal (AD) desmoid tumor. The tested proteins demonstrated cytoplasmic (c) staining. Furthermore, nuclear (n) or cytoplasmic and nuclear (c+n) staining was observed for beta-catenin. The mean values of the percentage of positive cells for the tested proteins between E-AD vs. AD did not demonstrate any statistically significant difference except for alpha-catenin. In the E-AD group, in both cases of recurrent tumors, no alpha-catenin expression was observed but the expression of this protein was detected in primary tumors. In the groups investigated, no statistically significant correlation was found between alpha-catenin, beta-catenin (c), (n) and (c+n) expression, and tumor size (p>0.1). The results regarding beta-catenin expression obtained in our study confirm the previous findings that nuclear accumulation of this protein plays a crucial role in the pathogenesis of aggressive fibromatosis.


Assuntos
Proteína da Polipose Adenomatosa do Colo/biossíntese , Caderinas/biossíntese , Fibromatose Agressiva/metabolismo , alfa Catenina/biossíntese , beta Catenina/biossíntese , Adulto , Fatores Etários , Idoso , Biomarcadores Tumorais/análise , Feminino , Fibromatose Agressiva/patologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Adulto Jovem
15.
Anticancer Res ; 28(3B): 1821-30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18630466

RESUMO

UNLABELLED: Beta-catenin is a component of the Wingless/Wnt signaling pathway and can activate target genes associated with proliferation and invasion, linking with the APC gene. The purpose of this study was to investigate whether nuclear expression of beta-catenin in cells at the invasive front or in the vessels was associated with liver metastasis in human colon cancer. PATIENTS AND METHODS: One hundred and eighteen patients with colorectal carcinoma who underwent surgical resection (45 patients with liver metastasis and 73 patients without liver metastasis at least 5 years after surgery) were included in the study. Proliferative activity was determined in several areas (tumor center, invasive front and in the vessels) by immunohistochemistry and whether it was correlated with liver metastasis was examined. RESULTS: In 73.1% of primary tumors, positive staining for beta-catenin was detected in the membranes at the tumor center and in the nuclei at the invasive front. In 32 patients (26.9% of all cases), beta-catenin was expressed exclusively in the nuclei of the carcinoma cells throughout the tumors. Significant differences in expression of nuclear beta-catenin in the primary tumors were detected between the liver metastasis and non-liver metastasis groups at the tumor center (p=0.004), invasive front (p=0.021) and in the vessels (p<0.0001). CONCLUSION: Nuclear accumulation of beta-catenin in cellular cells at the invasive front and in the vessels was the most powerful predictor of liver metastasis in colorectal cancer. This may be an important marker in the selection of patients for adjuvant therapy or other treatment modalities.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , beta Catenina/biossíntese , Caderinas/biossíntese , Núcleo Celular/metabolismo , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , alfa Catenina/biossíntese
16.
Can J Physiol Pharmacol ; 86(3): 105-12, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18418437

RESUMO

Epithelial cells form a tight barrier against environmental stimuli via tight junctions (TJs) and adherence junctions (AJs). Defects in TJ and AJ proteins may cause changes in epithelial morphology and integrity and potentially lead to faster trafficking of inflammatory cells through the epithelium. Bronchial epithelial fragility has been reported in asthmatic patients, but little is known about the expression of TJ and AJ proteins in asthma. We studied epithelial expression of zonula occludens-1 (ZO-1) and AJ proteins E-cadherin, alpha-catenin, and beta-catenin in bronchial biopsies from nonatopic nonasthmatic (healthy) subjects (n = 14), and stable atopic asthmatic subjects (n = 22) at baseline conditions. Immunostaining for these proteins was semi-quantified for separate cellular compartments. E-cadherin, alpha-catenin and beta-catenin were present in the cellular membrane and less in the cytoplasm. Only beta-catenin was present in the nucleus in agreement with its potential function as transcription factor. ZO-1 was present in the apicolateral membrane of superficial cells. alpha-Catenin expression was significantly lower in subjects with asthma than without and correlated inversely with numbers of eosinophils within the epithelium. ZO-1 and E-cadherin expression were significantly lower in asthmatic than in nonasthmatic subjects. Expression of beta-catenin was not different. Our results suggest that the lower epithelial alpha-catenin, E-cadherin and (or) ZO-1 expression in patients with atopic asthma contributes to a defective airway epithelial barrier and a higher influx of eosinophils in the epithelium.


Assuntos
Asma/metabolismo , Caderinas/biossíntese , Inserção Epitelial/química , Proteínas de Membrana/biossíntese , Fosfoproteínas/biossíntese , alfa Catenina/biossíntese , beta Catenina/biossíntese , Asma/patologia , Brônquios/química , Brônquios/patologia , Moléculas de Adesão Celular/biossíntese , Eosinófilos/química , Eosinófilos/patologia , Inserção Epitelial/patologia , Células Epiteliais/química , Células Epiteliais/patologia , Humanos , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Junções Intercelulares/química , Junções Intercelulares/patologia , Mucosa/química , Mucosa/patologia , Proteína da Zônula de Oclusão-1
17.
Pathol Res Pract ; 203(7): 517-23, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17576040

RESUMO

The sentinel node (SN) technique has gained a key role in breast cancer surgery, allowing for an accurate staging of the axillary status with a minimally invasive resection. In this study, we explored the implication of three proteins (E-cadherin, a- and b-catenins) that form the cadherin-catenin complex, a receptorial structure strictly involved in tumoral vascular invasion and embolization in this biologic event. We studied the immunohistochemical expression of the complex in patients with metastatic SN, matching the group with involved nonsentinel lymph nodes (NSNs) with that having free axillary NSNs. The simultaneous staining of the SN metastases for the three proteins has been considered an indicator of preserved function. Our data confirmed the lack of cadherin-catenin complex in tumors with lobular morphology even in SN metastasis, but statistical evaluation could not prove a significant relation between complex integrity and NSN involvement. Moreover, considering traditional histopathologic parameters, only vascular peritumoral embolization was related to an increased risk of metastatic spread to axillary NSNs.


Assuntos
Neoplasias da Mama/metabolismo , Caderinas/biossíntese , Metástase Linfática/patologia , Biópsia de Linfonodo Sentinela , alfa Catenina/biossíntese , beta Catenina/biossíntese , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Feminino , Humanos , Imuno-Histoquímica
18.
J Surg Oncol ; 95(2): 148-55, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17262732

RESUMO

BACKGROUND AND OBJECTIVES: The purpose of the present study was to analyze clinicopathologic variables in esophageal squamous cell carcinoma (ESCC) according to expression of E-cadherin and alpha-catenin which play an important role in cell adhesion. METHODS: We immunohistochemically examined E-cadherin and alpha-catenin in 205 patients with ESCC. The expression results were classified into two groups: preserved expression (+) and reduced expression (-). RESULTS: The incidence of E-cadherin (-) and alpha-catenin (-) was 52% and 54%, respectively and significantly related each other. For both E-cadherin and alpha-catenin, reduced expression was significantly related to tumor depth, nodal metastasis, stage, recurrence, and prognosis. In the E-cadherin (+) group, the alpha-catenin (+) and alpha-catenin (-) patients differed significantly in tumor depth, nodal metastasis, stage, hematogenous and lymphatic recurrences (P < 0.001, <0.001, <0.001, <0.001 and =0.007, respectively). According to coexpression of E-cadherin and alpha-catenin, the prognosis was best in patients with E-cadherin (+) and alpha-catenin (+), and worst in patients with E-cadherin (-) and alpha-catenin (-). Multivariate analysis revealed that alpha-catenin expression was an independent prognostic factor. CONCLUSIONS: The examination of expression of E-cadherin and especially alpha-catenin is useful for predicting lymph node metastasis and clinical outcome of ESCC.


Assuntos
Caderinas/biossíntese , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Linfonodos/patologia , alfa Catenina/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Adesão Celular , Neoplasias Esofágicas/patologia , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico
19.
Pathol Res Pract ; 202(9): 639-50, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16843618

RESUMO

The E-cadherin/catenin complex (alpha-catenin, beta-catenin, and E-cadherin) plays a crucial role in cell-cell adhesion and tissue remodeling, and abnormalities in these molecules have been suggested to participate in the proliferation and invasive and metastatic potentials of several human carcinomas. However, in human lung adenocarcinomas, its importance has not yet been sufficiently investigated. We immunohistochemically examined the expressions of E-cadherin/catenin complex in 35 primary lung adenocarinomas, and evaluated their expressions in a semiquantitative manner. Correlations between these expression levels, MIB-1 and nuclear p53 indices, and clinicopathological factors were analyzed by subdividing the cases into high- and low-expression groups for each protein. The reduction in membranous E-cadherin/catenin complex expression correlated significantly with low-grade histological differentiation and with high MIB-1 index. Survival analyses were also performed to clarify which factors potentially affected the prognosis of lung adenocarcinoma patients. The low expression of beta-catenin and the high MIB-1 index had a significantly unfavorable influence on the patients' survival. Moreover, the immunohistochemical expression of beta-catenin by cancer cells and MIB-1 index are considered useful prognostic factors for lung adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Caderinas/biossíntese , Neoplasias Pulmonares/metabolismo , alfa Catenina/biossíntese , beta Catenina/biossíntese , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Feminino , História do Século XVIII , Humanos , Imuno-Histoquímica , Antígeno Ki-67/biossíntese , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Proteína Supressora de Tumor p53/biossíntese
20.
Zhonghua Nan Ke Xue ; 12(5): 394-6, 400, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16755864

RESUMO

OBJECTIVE: To study the expression of alpha-catenin in the rat testis after intra-testicular testosterone withdrawal induced by injection of testosterone undecanoate (TU). METHODS: Ten adult male SD rats received vehicle (n = 5 ) or TU (19 mg/kg every 15 days, n = 5) for 130 days. Paraffin-embedded testicular sections were used for immunohistochemistry against a polyclonal anti-alpha-catenin antibody. RESULTS: In the control, alpha-catenin was expressed in the acrosome of spermatids and the cytoplasm of Leydig cells and peritubular myoid cells. In the TU-treated rat testis, Leydig cells were atrophied and the expression of alpha-catenin was markedly decreased or absent, but there was no evident change in the immunostaining of spermatids or myoid cells. CONCLUSION: Intra-testicular testosterone withdrawal-induced looser arrangement or sloughing of spermatogenic cells is not related to the adhesion molecule alpha-catenin. Alpha-catenin may be used as a cell identification marker for Leydig cells.


Assuntos
Testículo/metabolismo , Testosterona/análogos & derivados , alfa Catenina/biossíntese , Animais , Imuno-Histoquímica , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testosterona/farmacologia
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