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1.
Onco Targets Ther ; 14: 4761-4777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531663

RESUMO

INTRODUCTION: Trefoil Factor (TFF) is a member of a protein family comprised of three isoforms, of which TFF-1 exhibits antithetical functions; promotion or suppression of cell proliferation, survival and invasion, depending on the cancer type. However, the pathobiological function of TFF-1 in lung carcinoma has been still unclear. METHODS: We examined the expression and secretion of TFF-1 using cultured human lung carcinoma cells by immunoblotting, immunofluorescence, enzyme-linked immunosorbent assay and quantitative real-time PCR analyses. The effects of TFF-1 on various phenotypes were analyzed in two cell lines, including those transfected with cDNA encoding TFF-1. Cell proliferation and death were examined by hemocytometer cell counting and by colorimetric viability/cytotoxicity assay. Cell cycle profile, migration and invasion were also examined by flow cytometry, wound healing assay and Matrigel Transwell assay, respectively. The effect of TFF-1 overexpression was confirmed by additional transfection of TFF-1-specific siRNA. RESULTS: Endogenous TFF-1 protein expression and secretion into the media were observed exclusively in adenocarcinoma-derived cell lines. Forced overexpression of TFF-1 drove cell cycle transition, while the proliferation decreased by 19% to 25% due to increased cell death. This cell death was predominantly caused by apoptosis, as assessed by the activation of caspase 3/7. Cell migration was also suppressed by 71% to 82% in TFF-1-transfected cells. The suppressive effect of TFF-1 on proliferation and migration was restored by transfection of TFF-1 siRNA. Moreover, invasion was also suppressed to 77% to 83% in TFF-1-transfected cells. CONCLUSION: These findings reveal that TFF-1 functions as a suppressor of cancer proliferation by induction of apoptosis, cell migration and invasion and thus may provide a synergistic target for potential treatment strategies for human lung carcinoma.

2.
Pathol Int ; 71(5): 326-336, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33657249

RESUMO

Breast tissue has a branching structure that contains double-layered cells, consisting primarily of luminal epithelial cells inside and myoepithelial cells outside. Ductal carcinoma in situ (DCIS) still has myoepithelial cells surrounding the cancer cells. However, myoepithelial cells disappear in invasive ductal carcinoma. In this study, we detected expression of neural EGFL like (NELL) 2 and one of its receptors, roundabout guidance receptor (ROBO) 3, in myoepithelial and luminal epithelial cells (respectively) in normal breast tissue. NELL2 also was expressed in myoepithelial cells surrounding the non-cancerous intraductal proliferative lesions and DCIS. However, the expression level and proportion of NELL2-positive cells in DCIS were lower than those in normal and non-cancerous intraductal proliferative lesions. ROBO3 expression was decreased in invasive ductal carcinoma compared to that in normal and non-cancerous intraductal proliferative lesions. An evaluation of NELL2's function in breast cancer cell lines demonstrated that full-length NELL2 suppressed cell adhesion and migration in vitro. In contrast, the N-terminal domain of NELL2 increased cell adhesion in the early phase and migration in vitro in some breast cancer cells. These results suggested that full-length NELL2 protein, when expressed in myoepithelial cells, might serve as an inhibitor of breast cancer cell migration.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Receptores de Superfície Celular/metabolismo , Biomarcadores Tumorais/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos
3.
Int J Clin Exp Pathol ; 13(8): 2201-2210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922621

RESUMO

We previously reported that miR-200a was highly up-regulated in lung carcinoma, exhibiting a copy number increase (CNI) of the AKT2 gene (AKT2+ group) in defined subsets, i.e., adenocarcinoma and early stages of carcinoma (pStage I/II). In this study, we searched possible targets of miR-200a in these subsets by IHC analyses focusing on the expression of known target proteins of miR-200a: beta-catenin, EphA2, ZEB1, PTEN, and YAP-1, as well as E-cadherin, the expression of which is suppressed by ZEB1. Among those 6 proteins, when all 38 cases of surgically resected specimens were analyzed as a whole, IHC score of ZEB1 was inversely (ρ=-.417) and E-cadherin was positively (ρ=.345) correlated with miR-200a expression. However, only EphA2 was inversely correlated with the expression of miR-200a in adenocarcinoma (ρ=-.496) and in pStage I/II group (ρ=-.547), while no correlation was seen in non-adenocarcinoma, squamous cell carcinoma, or pStage III carcinoma. Furthermore, by comparison of 3 groups categorized according to the AKT gene increase, only EphA2 was down-regulated to a statistically significant level in the AKT2+ group in both adenocarcinoma (p=.0447) and pStage I/II carcinoma (p=.0458). These results suggest that in lung carcinomas, higher Akt activation caused by increased AKT2 gene copy number leads to the upregulation of miR-200a, which exerts its function as a suppressor of EphA2 in adenocarcinoma and the early stages of carcinomas.

4.
Pathol Int ; 70(6): 330-339, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32103597

RESUMO

Most breast cancers are derived from the luminal epithelium, which composes the inside of the breast ductal structure. Ductal carcinoma in situ (DCIS) leads to invasive ductal carcinoma, but noncancerous intraductal proliferative lesions are also a risk factor for ductal carcinoma. The transforming growth factor beta (TGFB) signaling pathway behaves as a tumor suppressor in the early stage of cancer, and conversely as a tumor growth factor in invasive stages in several cancers. In this study, we performed immunohistochemistry with an antibody that detects the cytoplasmic region of TGFB receptor 1 (TGFBR1) and elucidated TGFBR1 protein expression in luminal epithelial cells of noncancerous breast ducts and in several cases of DCIS and invasive carcinoma. TGFBR1 expression was higher in noncancerous breast tissue than in cancerous tissue, and a difference in expression was also seen among histological subtypes. Comparing the expression level of TGFBR1 in cancer cells and clinico-pathological parameters, cases expressing low TGFBR1 tended to show low estrogen receptor expression, large tumor size (≥10 mm), and a high Ki67 labeling index. These data suggested that TGFBR1 protein expression may be related to the suppression of breast cancer cell growth.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Intraductal não Infiltrante , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo I/análise , Receptores de Estrogênio/metabolismo
5.
Hum Pathol ; 85: 33-43, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30385370

RESUMO

Gene amplification is a common event in breast cancer, and identifies actual and potential targets of molecular therapy. The aim of the present study was to determine the amplification status of 22 genes that are reportedly frequently amplified in breast cancers. An archive of 322 formalin-fixed and paraffin-embedded invasive breast cancer tissues were screened by multiple ligation-dependent probe amplification (MLPA) and a total of 906 gene loci judged as 'gain' or 'amplified' was further confirmed to have been amplified based on fluorescence in situ hybridization (FISH). The results showed that 109 of 322 tumors (34%) displayed gene amplification of at least one of the 22 genes. The frequencies of the amplification of four regions containing known driver oncogenes were as follows: 8p11 (ZNF703, FGFR1, ADAM9, IKBKB), 8q24 (MYC), 11q13 (CCND1, C11ORF30), and 17q11-21 (CPD, MED1, ERBB2, CDC6, TOP2A, MAPT) exhibited amplification in 9.6%, 9.6%, 12.4%, and 12.1% of the tumors, respectively. In addition to homogeneously staining region- or double-minute chromosome-type amplifications, a centromere-associated-type amplification was found in nine tumors. Co-localization of the amplicon on 8p11 and the amplicon on 11q13 in single cells was found in 10 tumors, and in six of those tumors the two amplicons constituted single amplification units. Similarly, an amplicon consisting of ERBB2 and its flanking genes on 17q12-21 co-localized with an amplicon on 8p11 in 10 tumors and with the amplicon on 11q13 in five tumors. Thus, precise and feasible analysis of gene amplification status can be obtained using a combination of MLPA and FISH.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Amplificação de Genes , Neoplasias da Mama/patologia , Feminino , Frequência do Gene , Humanos , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase Multiplex
7.
Hum Pathol ; 61: 58-67, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27864121

RESUMO

New and effective treatments for advanced gastric cancer are urgently needed. Cyclins E and D1 form a complex with cyclin-dependent kinase 2, 4, or 6 to regulate G1-S transition. The G1-S regulatory genes encoding cyclin E (CCNE1), cyclin D1 (CCND1), and CDK6 (CDK6) are frequently amplified in gastric cancer and may therefore influence molecularly targeted therapies against ERBB2 or EGFR when coamplified. A total of 179 formalin-fixed and paraffin-embedded gastric cancer specimens were examined for these gene amplifications by multiplex ligation-dependent probe amplification and fluorescence in situ hybridization. Amplification of at least 1 G1-S regulatory gene was found in 35 tumors (CCNE1 amplification, 15% of samples; CCND1, 6%; CDK6, 1%). In 13 of the 35 tumors, dual-color fluorescence in situ hybridization identified coamplification of the G1-S regulatory genes with ERBB2, EGFR, and/or KRAS in single cancer nuclei. The observation that cells with G1-S regulatory gene amplification contained clonal subpopulations with coamplification of ERBB2, EGFR, or KRAS in 5 early and 3 advanced cancers suggests that amplification of the G1-S regulatory genes represents an early event, which precedes ERBB2, EGFR, or KRAS amplification. Amplified CCNE1, CCND1, and CDK6 in advanced gastric cancer may be potentially useful as direct targets for molecular therapy or for combination therapy with ERBB2 or EGFR inhibitors. Multiplex ligation-dependent probe amplification could be a useful tool for identification of patients who would benefit from such therapies.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Ciclina D1/genética , Ciclina E/genética , Quinase 6 Dependente de Ciclina/genética , Amplificação de Genes , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase Multiplex , Proteínas Oncogênicas/genética , Neoplasias Gástricas/genética , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Biópsia , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Receptores ErbB/genética , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Mutação , Fenótipo , Valor Preditivo dos Testes , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor ErbB-2/genética , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia
8.
Pathol Int ; 65(11): 608-13, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26314265

RESUMO

EGFR and ERBB2 belong to the EGFR gene family. In esophageal squamous cell carcinomas (SCCs), amplification of EGFR or ERBB2 is usually mutually exclusive. EGFR amplification occurs in approximately 15% of SCCs, ERBB2 occurs in less than 5%. Here, we report the co-amplification of EGFR and ERBB2 in an ulcerative and infiltrating-type SCC that measured approximately 4.2 × 2.7 × 1.2 cm with a superficial lesion occurring in the thoracic esophagus of a 72-year-old man. Multiplex ligation-dependent probe amplification using representative tumor sections showed gain of CCND1 and coincident amplification of ERBB2 or EGFR or neither. Immunohistochemistry and fluorescence in situ hybridization revealed that the tumor comprised three cancer-cell populations: well-differentiated SCC with high-level ERBB2 amplification and ERBB2 overexpression, more infiltrative poorly-differentiated SCC with high-level EGFR amplification and EGFR overexpression, and poorly-differentiated SCC lacking any ERBB2 or EGFR abnormality. These three populations each had low-level CCND1 amplification and nuclear cyclin D1 overexpression. This histological topology and gene amplification combinations suggested that genetic instability first produced CCND1 amplification, and then ERBB2 or EGFR gene amplification occurred. It is further speculated that during cancer progression and clonal selection indecisive predominance of either clone caused the rare co-amplification of ERBB2 and EGFR in a single chimeric tumor.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Receptores ErbB/genética , Neoplasias Esofágicas/metabolismo , Amplificação de Genes/genética , Receptor ErbB-2/genética , Idoso , Carcinoma de Células Escamosas do Esôfago , Amplificação de Genes/fisiologia , Humanos , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Masculino , Receptor ErbB-2/metabolismo
9.
Mod Pathol ; 28(6): 861-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25743022

RESUMO

The prognosis of patients with gastric carcinomas at an advanced stage still remains dismal, and therefore novel therapeutic modalities are urgently needed. Since the successful targeting of amplified ERBB2 with a humanized monoclonal antibody, the amplified genes of other receptor tyrosine kinases such as EGFR, FGFR2, and MET, as well as those of other cell regulator genes, are being considered as candidate targets of molecular therapy. The aim of the present study was to determine the amplification status of 26 genes, which are frequently amplified in solid cancers, in advanced gastric cancers. A total of 93 formalin-fixed and paraffin-embedded advanced gastric cancer tissues were examined by multiple ligation-dependent probe amplification, and 32 cases with 'gain' or 'amplified' status of 16 genes were further examined for the respective gene amplification by fluorescence in situ hybridization (FISH) and for the respective protein overexpression by immunohistochemistry. The frequencies of gene amplifications in advanced gastric cancers were as follows: ERBB2 (13 cases, 14%), FGFR2 (7 cases, 8%), MYC (7 cases, 8%), TOP2A (7 cases, 8%), MET (4 cases, 4%), MDM2 (4 cases, 4%), CCND1 (3 cases, 3%), FGF10 (2 cases, 3%), and EGFR (1 case, 1%). Amplification of the receptor tyrosine kinases genes occurred in a mutually exclusive manner except for one tumor in which ERBB2 and FGFR2 were both amplified but in different cancer cells. Co-amplification of ERBB2 and MYC, and EGFR and CCND1, in single nuclei but on different amplicons, was confirmed in one case each. Attempts at correlating the FISH status with the immunohistochemical staining pattern showed variable results from complete concordance to no correlation. In conclusion, combination of multiple ligation-dependent probe amplification and FISH analysis is a feasible approach for obtaining the semi-comprehensive genetic information that is necessary for personalized molecular targeted therapy.


Assuntos
Adenocarcinoma/genética , Hibridização in Situ Fluorescente/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Neoplasias Gástricas/genética , Amplificação de Genes , Humanos , Imuno-Histoquímica
10.
Cancer Sci ; 106(5): 656-64, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25726761

RESUMO

Neural epidermal growth factor-like like (NELL) 1 and 2 constitute a family of multimeric and multimodular extracellular glycoproteins. Although the osteogenic effects of NELL1 and functions of NELL2 in neural development have been reported, their expression and functions in cancer are largely unknown. In this study, we examined expression of NELL1 and NELL2 in renal cell carcinoma (RCC) using clinical specimens and cell lines. We show that, whereas NELL1 and NELL2 proteins are strongly expressed in renal tubules in non-cancerous areas of RCC specimens, their expression is significantly downregulated in cancerous areas. Silencing of NELL1 and NELL2 mRNA expression was also detected in RCC cell lines. Analysis of NELL1/2 promoter methylation status indicated that the CpG islands in the NELL1 and NELL2 genes are hypermethylated in RCC cell lines. NELL1 and NELL2 bind to RCC cells, suggesting that these cells express a receptor for NELL1 and NELL2 that can transduce signals. Furthermore, we found that both NELL1 and NELL2 inhibit RCC cell migration, and NELL1 further inhibits RCC cell adhesion. These results suggest that silencing of NELL gene expression by promoter hypermethylation plays roles in RCC progression by affecting cancer cell behavior.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Proteínas do Tecido Nervoso/metabolismo , Idoso , Azacitidina/farmacologia , Proteínas de Ligação ao Cálcio , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Movimento Celular , Ilhas de CpG , Metilação de DNA , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Regiões Promotoras Genéticas
11.
Pathol Int ; 64(5): 231-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24888777

RESUMO

A needle biopsy of a mass in the right breast of a 36-year-old woman revealed invasive ductal carcinoma (IDC), and approximately 20% of cancer cells showed unequivocal membranous staining with the HercepTest. After systemic therapy with trastuzumab and paclitaxel followed by FEC (fluorouracil + epirubicin + cyclophosphamide), a right mastectomy was performed. By histological and immunohistochemical examinations, the resected tumor consisted mainly of E-cadherin-negative invasive lobular carcinoma (ILC), and the rest was ERBB2-positive IDC; thus, the diagnosis was mixed ductal and lobular carcinoma. Multiplex ligation-dependent probe amplification and fluorescence in situ hybridization (FISH) analyses revealed that ILC and IDC shared high-level amplification of CCND1 in homogeneously staining regions (HSR) and that IDC had an additional HSR-type amplicon of ERBB2. These findings strongly indicate that IDC and ILC had a common precursor cell with CCND1 amplification. Review of the biopsy specimen with FISH showed IDC with gene amplifications of CCND1 and ERBB2 as a minor component, IDC without amplification of CCND1 or ERBB2 as a major component, and a minute portion of ILC with CCND1 amplification. We speculate that chemotherapy and trastuzumab caused a marked reduction in IDC; however, ILC with CCND1 amplification was resistant to chemotherapy and grew.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Impressões Digitais de DNA/métodos , DNA de Neoplasias/genética , Hibridização in Situ Fluorescente/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Adulto , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/terapia , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Humanos , Mastectomia , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Resultado do Tratamento
12.
Hum Pathol ; 45(4): 725-34, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24491355

RESUMO

A humanized monoclonal antibody against ERBB2 is used in neoadjuvant therapy for patients with gastric cancer. A critical factor in determining patient eligibility and predicting outcomes of this therapy is the intratumoral heterogeneity of ERBB2 amplification in gastric adenocarcinomas. The aims of this study are to assess the underlying mechanisms of intratumoral heterogeneity of ERBB2 amplification; to characterize the diversity of coamplified oncogenes such as EGFR, FGFR2, MET, MYC, CCND1, and MDM2; and to examine the usefulness of multiple ligation-dependent probe amplification (MLPA) in the semicomprehensive detection of these gene amplifications. A combined analysis of immunohistochemistry and fluorescence in situ hybridization revealed ERBB2-amplified cancer cells in 51 of 475 formalin-fixed, paraffin-embedded gastric adenocarcinomas. The fraction of amplification-positive cells in each tumor ranged from less than 10% to almost 100%. Intratumoral heterogeneity of ERBB2 amplification, defined as less than 50% of cancer cells positive for ERBB2 amplification, was found in 41% (21/51) of ERBB2-amplified tumors. The combined analysis of MLPA and fluorescence in situ hybridization revealed that ERBB2 was coamplified with EGFR in 7 tumors, FGFR2 in 1 tumor, and FGFR2 and MET in 1 tumor; however, the respective genes were amplified in mutually exclusive cells. Coamplified ERBB2 and MYC coexisted within single nuclei in 4 tumors, and one of these cases had suspected coamplification in the same amplicon of ERBB2 with MYC. In conclusion, the amplification status of ERBB2 and other genes can be obtained semicomprehensively by MLPA and could be useful to plan individualized molecularly targeted therapy against gastric cancers.


Assuntos
Adenocarcinoma/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Receptor ErbB-2/genética , Neoplasias Gástricas/genética , Amplificação de Genes , Genes erbB-2/genética , Genes myc/genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptor ErbB-2/análise , Receptor ErbB-2/metabolismo
13.
J Biol Chem ; 287(5): 3282-91, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22157752

RESUMO

Nel (neural epidermal growth factor (EGF)-like molecule) is a multimeric, multimodular extracellular glycoprotein with heparin-binding activity and structural similarities to thrombospondin-1. Nel is predominantly expressed in the nervous system and has been implicated in neuronal proliferation and differentiation, retinal axon guidance, synaptic functions, and spatial learning. The Nel protein contains an N-terminal thrombospondin-1 (TSP-N) domain, five cysteine-rich domains, and six EGF-like domains. However, little is known about the functions of specific domains of the Nel protein. In this study, we have performed structure-function analysis of Nel, by using a series of expression constructs for different regions of the Nel protein. Our studies demonstrate that the TSP-N domain is responsible for homo-multimer formation of Nel and its heparin-binding activity. In vivo, Nel and related Nell1 are expressed in several regions of the mouse central nervous system with partly overlapping patterns. When they are expressed in the same cells in vitro, Nel and Nell1 can form hetero-multimers through the TSP-N domain, but they do not hetero-oligomerize with thrombospondin-1. Whereas both the TSP-N domain and cysteine-rich domains can bind to retinal axons in vivo, only the latter causes growth cone collapse in cultured retinal axons, suggesting that cysteine-rich domains interact with and activate an inhibitory axon guidance receptor. These results suggest that Nel interacts with a range of molecules through its different domains and exerts distinct functions.


Assuntos
Sistema Nervoso Central/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Cones de Crescimento/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Multimerização Proteica/fisiologia , Trombospondina 1 , Animais , Embrião de Galinha , Células HEK293 , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Estrutura Terciária de Proteína
14.
World J Gastrointest Oncol ; 2(12): 421-8, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21191536

RESUMO

Ever since its discovery two decades ago, the erythropoietin-producing hepatoma (EPH)-EPHRIN system has been shown to play multifaceted roles in human gastroenterological cancer as well as neurodevelopment. Over-expression, amplification and point mutations have been found in many human cancers and many investigators have shown correlations between these up-regulations and tumor angiogenesis. Thus, the genes in this family are considered to be potential targets of cancer therapy. On the other hand, the down-regulation of some members as a result of epigenetic changes has also been reported in some cancers. Furthermore, the correlation between altered expressions and clinical prognosis seems to be inconclusive. A huge amount of protein-protein interaction studies on the EPH-EPHRIN system have provided a basic scheme for signal transductions, especially bi-directional signaling involving EPH-ERPHRIN molecules at the cell membrane. This information also provides a manipulative strategy for harnessing the actions of these molecules. In this review, we summarize the known alterations of EPH-EPHRIN genes in human tumors of the esophagus, stomach, colorectum, liver and pancreas and present the perspective that the EPH-EPHRIN system could be a potential target of cancer therapy.

15.
Mol Cell Neurosci ; 41(2): 113-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19249368

RESUMO

Nel is a glycoprotein containing five chordin-like and six epidermal growth factor-like domains and is strongly expressed in the nervous system. In this study, we have examined expression patterns and in vitro functions of Nel in the chicken retinotectal system. We have found that in the developing tectum, expression of Nel is localized in specific laminae that retinal axons normally do not enter, including the border between the retinorecipient and non-retinorecipient laminae. Nel-binding activity is detected on retinal axons both in vivo and in vitro, suggesting that retinal axons express a receptor for Nel. In vitro, Nel inhibits retinal axon outgrowth and induces growth cone collapse and axon retraction. These results indicate that Nel acts as an inhibitory guidance cue for retinal axons, and suggest its roles in the establishment of the lamina-specificity in the retinotectal projection.


Assuntos
Axônios/metabolismo , Movimento Celular/fisiologia , Glicoproteínas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Células Ganglionares da Retina , Teto do Mesencéfalo/citologia , Animais , Axônios/ultraestrutura , Embrião de Galinha , Glicoproteínas/genética , Proteínas do Tecido Nervoso/genética , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/fisiologia , Transdução de Sinais/fisiologia , Técnicas de Cultura de Tecidos
16.
Oncogene ; 24(36): 5637-47, 2005 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-16007213

RESUMO

A significant reduction of EphA7 expression in human colorectal cancers was shown using semiquantitative reverse transcription-polymerase chain reaction analysis in 59 colorectal cancer tissues, compared to corresponding normal mucosas (P=0.008), and five colon cancer cell lines. To investigate the mechanism of EphA7 downregulation in colorectal cancer, we examined the methylation status of the 5'CpG island around the translation start site in five colon cancer cell lines using restriction enzymes, methylation-specific PCR, and bisulfite sequencing and found evidence of aberrant methylation. The expression of EphA7 in colon cancer cell lines was restored after treatment with 5-aza-2'-deoxycytidine. Analysis of methylation status in totally 75 tumors compared to clinicopathological parameters revealed that hypermethylation of colorectal cancers was more frequent in male than in female (P=0.0078), and in moderately differentiated than in well-differentiated adenocarcinomas (P=0.0361). There was a tendency that hypermethylation in rectal cancers was more frequent than in colon cancers (P=0.0816). Hypermethylation was also observed in colorectal adenomas. This is the first report describing the downregulation of an Eph family gene in a solid tumor via aberrant 5'CpG island methylation. It provides the evidence that EphA7 gene is involved in human colorectal carcinogenesis.


Assuntos
Neoplasias Colorretais/genética , Metilação de DNA , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Receptor EphA7/genética , Idoso , Linhagem Celular , Neoplasias Colorretais/classificação , Neoplasias Colorretais/patologia , Ilhas de CpG , Feminino , Inativação Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Caracteres Sexuais
17.
Cancer Sci ; 96(1): 42-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15649254

RESUMO

The erythropoietin-producing hepatocellular (EPH)A2 receptor, tyrosine kinase, is overexpressed and phosphorylated in several types of human tumors and has been associated with malignant transformation. A recent report, however, indicated that stimulation of the EPHA2 receptor ligand, ephrinA1 (EFNA1), inhibits the growth of EPHA2-expressing breast cancer. The authors examined the expression of EPHA2 and EFNA1 using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) in four gastric cancer cell lines and 49 primary gastric cancer samples, as well as in normal gastric tissue. EPHA2 was more highly expressed in tumor tissue than in normal tissue in 27 cases (55%). EFNA1 was overexpressed in tumor tissue in 28 cases (57%). No significant correlation was detected between the expression levels and histologic features such as tumor size, age, vessel invasion, or lymph node involvement. However, EPHA2 overexpression was more prominent in macroscopic type 3 and 4 tumors than in type 1 or 2 advanced gastric cancer. The authors observed EPHA2 expression in three of the four gastric cancer cell lines (AGS, KATO3, and MKN74) that were examined. In one cell line, TMK1, EPHA2 expression was barely detectable using northern blotting, RT-PCR, and western blotting. In contrast, EFNA1 was detected in all cell lines. In the gastric cancer cell lines that endogenously expressed EPHA2, stimulation with ephrinA1-Fc led to decreased EPHA2 protein expression and increased EPHA2 phosphorylation. Finally, the growth of EPHA2-expressing cells was inhibited by repetitive stimulation with soluble ephrinA1-Fc. Taken together, these findings suggest that EPHA2 and EFNA1 expression may influence the behavior of human gastric cancer.


Assuntos
Efrina-A1/biossíntese , Receptor EphA2/biossíntese , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Northern Blotting , Western Blotting , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
EMBO J ; 23(5): 1075-88, 2004 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-14988728

RESUMO

Bidirectional signals mediated by Eph receptor tyrosine kinases and their membrane-bound ligands, ephrins, play pivotal roles in the formation of neural networks by induction of both collapse and elongation of neurites. However, the downstream molecular modules to deliver these cues are largely unknown. We report here that the interaction of a Rac1-specific guanine nucleotide-exchanging factor, Tiam1, with ephrin-B1 and EphA2 mediates neurite outgrowth. In cells coexpressing Tiam1 and ephrin-B1, Rac1 is activated by the extracellular stimulation of clustered soluble EphB2 receptors. Similarly, soluble ephrin-A1 activates Rac1 in cells coexpressing Tiam1 and EphA2. Cortical neurons from the E14 mouse embryos and neuroblastoma cells significantly extend neurites when placed on surfaces coated with the extracellular domain of EphB2 or ephrin-A1, which were abolished by the forced expression of the dominant-negative mutant of ephrin-B1 or EphA2. Furthermore, the introduction of a dominant-negative form of Tiam1 also inhibits neurite outgrowth induced by the ephrin-B1 and EphA2 signals. These results indicate that Tiam1 is required for neurite outgrowth induced by both ephrin-B1-mediated reverse signaling and EphA2-mediated forward signaling.


Assuntos
Efrina-A2/metabolismo , Efrina-B1/metabolismo , Neuritos/metabolismo , Proteínas/metabolismo , Animais , Tamanho Celular , Células Cultivadas , Chlorocebus aethiops , Citoplasma/metabolismo , Efrina-A2/genética , Efrina-B1/genética , Fatores de Troca do Nucleotídeo Guanina , Humanos , Camundongos , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas/genética , Transdução de Sinais , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T , Proteínas rac1 de Ligação ao GTP/metabolismo
19.
Surg Today ; 34(1): 68-71, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14714233

RESUMO

Cytomegalovirus (CMV) infection has been reported to be a cause of refractory ulcerative colitis (UC). We herein report a case of refractory ulcerative colitis complicated by CMV infection requiring surgery. A 22-year-old man was admitted to our hospital with lower abdominal pain and bloody diarrhea. Under a diagnosis of acute UC, he was treated with prednisone 60 mg/day and sulfasalazine. Since his symptoms appeared to improve, the prednisone dosage was gradually reduced to 20 mg/day. After 5 months, he had an unexpected flare-up with fever and fresh anal bleeding. Colonoscopy demonstrated a punched out ulcer in the sigmoid colon. Biopsies by colonoscopy revealed cytomegalic inclusion bodies. Serologic and immunologic studies also suggested a recent CMV infection. Under a diagnosis of intractable UC complicated by a CMV infection, ganciclovir therapy was carried out, and the steroid therapy was tapered. Although the serum antigenemia became negative after the antiviral therapy, follow-up colonoscopy confirmed the severe stenosis after the punched-out ulcer healed completely. Since his symptoms did not improve, it was necessary to perform an elective proctocolectomy despite antiviral therapy. He was discharged with an uneventful postoperative course. It is important to recognize CMV colitis as a complication of inflammatory bowel disease, particularly in severe steroid-resistant colitis. Furthermore, in cases which fail to respond to antiviral treatment, the patient may ultimately require surgery.


Assuntos
Colite Ulcerativa/cirurgia , Colite Ulcerativa/virologia , Infecções por Citomegalovirus/complicações , Adulto , Antivirais/uso terapêutico , Colonoscopia , Infecções por Citomegalovirus/tratamento farmacológico , Humanos , Masculino , Proctocolectomia Restauradora
20.
Jpn J Clin Oncol ; 33(9): 463-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14594940

RESUMO

BACKGROUND: Chromosomal numerical abnormality (CNA) is a characteristic of breast cancer as with other common solid cancers. Multiple mammary carcinomas are also sometimes encountered in the ipsilateral breast. Deciding whether they are multicentric (arising independently) or multifocal (of the same origin) has been a continued challenge to clinicians and pathologists. METHODS: We experienced two cases of macroscopically distinct double carcinomas in the ipsilateral breast, in which two cancers had a different histopathological morphology. Centromere probes identifying 17 different and specific centromeres were used to obtain the profile of CNA for each tumor, with a microwave-assisted FISH protocol. For comparison, a case of three lesions, two of which had the same and the other different histology was also studied. RESULTS: Contrary to our expectations, in spite of the particular difference in the histopathological picture of these tumors, the CNA profile was the same in one case and different in the other. The gain of chromosome 1 and loss of chromosome 15 are representative features shared by multifocal cases. On the other hand, the multiple cancers with the same histology had mostly the same CNA profile. CONCLUSIONS: CNA profiling is useful to identify the lineage of multiple breast cancers. As shown here, regardless of the histological features, a certain common CNA profile can define the same origin of some multiple cancers.


Assuntos
Adenocarcinoma Mucinoso/genética , Adenocarcinoma Esquirroso/genética , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Aberrações Cromossômicas , Neoplasias Primárias Múltiplas/genética , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Esquirroso/patologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Cariotipagem , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Inclusão em Parafina
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