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1.
Sci Rep ; 9(1): 12687, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481738

RESUMO

The microenvironment in classical Hodgkin lymphoma (cHL) comprises a mixture of different types of cells, which are responsible for lymphoma pathogenesis and progression. Even though microenvironment composition in adult cHL has been largely studied, only few groups studied pediatric cHL, in which both Epstein Barr virus (EBV) infection and age may display a role in their pathogenesis. Furthermore, our group described that EBV is significantly associated with cHL in Argentina in patients under the age of 10 years old. For that reason, our aim was to describe the microenvironment composition in 46 pediatric cHL patients. M1-like polarization status prevailed in the whole series independently of EBV association. On the other hand, in children older than 10 years, a tolerogenic environment illustrated by higher FOXP3 expression was proved, accompanied by a macrophage polarization status towards M2. In contrast, in children younger than 10 years, M1-like was prevalent, along with an increase in cytotoxic GrB+ cells. This study supports the notion that pediatric cHL exhibits a particular tumor microenvironment composition.


Assuntos
Doença de Hodgkin/patologia , Macrófagos/imunologia , Adolescente , Argentina , Criança , Pré-Escolar , Análise por Conglomerados , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Fatores de Transcrição Forkhead/metabolismo , Granzimas/metabolismo , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/etiologia , Doença de Hodgkin/imunologia , Humanos , Ativação de Macrófagos , Macrófagos/citologia , Macrófagos/metabolismo , Microambiente Tumoral
3.
Pathologe ; 36(5): 477-84, 2015 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-26280511

RESUMO

Macrophages are important factors in the pathogenesis and prognosis of malignant tumors and represent a possible target for therapeutic intervention. Depending on the tumor entity and the prevalent polarization status, macrophages can be associated with a favorable or unfavorable clinical outcome. It is becoming clear, however, that the conventional definitions of M1 polarized tumor inhibitory and M2 polarized tumor promoting macrophages do not adequately reflect the heterogeneity and plasticity of macrophages. Macrophages can support tumor growth through direct interactions with the neoplastic cells, by promoting tissue remodeling and angiogenesis and by inhibiting local immune reactions. To achieve comparability of clinical studies, it will be necessary to reach a consensus nomenclature of macrophage polarization. Furthermore, methods for the quantitative characterization of macrophage populations in malignant tumors will have to be standardized. It is unlikely that single marker immunohistochemistry will be adequate in this context. In any case it is necessary to provide unequivocal information regarding the markers or marker combinations used.


Assuntos
Diferenciação Celular/fisiologia , Macrófagos/patologia , Macrófagos/fisiologia , Neoplasias/patologia , Neoplasias/fisiopatologia , Plasticidade Celular/fisiologia , Polaridade Celular/fisiologia , Humanos , Tolerância Imunológica/fisiologia , Macrófagos/classificação , Neoplasias/irrigação sanguínea , Neoplasias/imunologia , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia
4.
Br J Cancer ; 106(12): 1980-8, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22588558

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) up-regulates the human leukocyte antigen (HLA) class I antigen presentation machinery (APM). This appears counterintuitive with immune evasion in EBV-associated tumours like nasopharyngeal carcinoma (NPC). METHODS: Latent membrane protein 1-transfected epithelial cell lines were used as a model system to study the impact of LMP1 and c-Myc on HLA class I components. The expression of components of the HLA class I APM, c-Myc and Ki-67 was analysed in LMP1+ and LMP1- NPC by immunohistochemistry. RESULTS: In epithelial cells, LMP1 up-regulated HLA class I APM. This effect could be counteracted by c-Myc, which itself was up-regulated by LMP1 apparently through IL6 induction and Jak3/STAT3 activation. Studies of NPC biopsies revealed down-regulation of HLA class I APM expression. No difference was observed between LMP1+ and LMP1- NPC. However, expression of Ki-67 and c-Myc were up-regulated in LMP1+ tumours. CONCLUSION: These findings raise the possibility that c-Myc activation in NPC might antagonise the effect of LMP1 on HLA class I expression thus contributing to immune escape of tumour cells.


Assuntos
Apresentação de Antígeno/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias Nasofaríngeas/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas da Matriz Viral/metabolismo , Carcinoma , Linhagem Celular Tumoral , Células Epiteliais/imunologia , Humanos , Interleucina-6/metabolismo , Carcinoma Nasofaríngeo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Regulação para Cima
5.
J Pathol ; 210(1): 26-31, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16783758

RESUMO

Activation-induced cytidine deaminase (AID) is essential for somatic hypermutation (SHM) and class switch recombination (CSR) of immunoglobulin genes in antigen-dependent B-cell maturation. SHM is not restricted to immunoglobulin gene loci, raising the possibility of a function for AID in other cell types. In this study, it is shown that AID is expressed in spermatocytes in the human testis. AID was mostly cytoplasmic but nuclear AID was also observed in a proportion of cells, in keeping with the DNA deamination model of AID function. Intratubular germ cell neoplasia unclassified (IGCNU), the precursor lesion of testicular cancers, was AID-negative. Seminomas also lacked AID expression. Nuclear and cytoplasmic AID expression was observed in three of 32 mixed non-seminomatous germ cell tumours. The results provide evidence for a physiological role for AID outside the immune system. AID expression in spermatocytes points to a role in meiosis. It remains uncertain whether AID may also contribute to the genetic aberrations characteristically found in testicular germ cell tumours. The consistent absence of detectable AID expression in atypical spermatogonia of IGCNU and its rare expression in germ cell tumours suggest that continued expression of AID is not involved in the pathogenesis of germ cell tumours.


Assuntos
Citidina Desaminase/análise , Neoplasias Embrionárias de Células Germinativas/enzimologia , Espermatogênese/fisiologia , Neoplasias Testiculares/enzimologia , Carcinoma Embrionário/enzimologia , Carcinoma Embrionário/genética , Contagem de Células , Linhagem Celular Tumoral , Tumor do Seio Endodérmico/enzimologia , Tumor do Seio Endodérmico/genética , Ativação Enzimática , Humanos , Imuno-Histoquímica/métodos , Masculino , Neoplasias Embrionárias de Células Germinativas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Seminoma/enzimologia , Seminoma/genética , Espermatogênese/genética , Teratoma/enzimologia , Teratoma/genética , Neoplasias Testiculares/genética
6.
J Pathol ; 209(4): 430-5, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16710842

RESUMO

We have previously developed two monoclonal antibodies against the Epstein-Barr Virus (EBV) nuclear antigen 1 (EBNA1), designated 1H4 and 2B4. Both detect EBNA1 by in situ staining in established EBV-positive tumours, e.g. Hodgkin's lymphoma and nasopharyngeal carcinoma. An association of EBV with other tumours, notably breast carcinomas, has been reported but remains controversial. Using the antibody 2B4, a nuclear protein has been detected in breast carcinomas that were EBV-negative by other methods, suggesting cross-reactivity with a cellular protein. Furthermore, an association of EBV with various other carcinomas has been reported on the basis of 2B4 immunohistochemistry. Here we show that 2B4 also binds to MAGE-4, a cancer testis antigen expressed in a variety of tumour cells, including breast carcinoma, seminoma and EBV-negative cases of Hodgkin's lymphoma. We conclude that the 2B4 antibody is not suitable for the detection of EBV infection but that additional techniques, particularly in situ hybridization for the detection of the EBV-encoded RNAs (EBERs), should be employed to confirm the presence of EBV. Our results add to the evidence indicating that breast cancer is not an EBV-associated disease.


Assuntos
Anticorpos Monoclonais , Antígenos CD/imunologia , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/análise , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas de Neoplasias/imunologia , Receptores Imunológicos/imunologia , Neoplasias da Mama/química , Carcinoma/química , Carcinoma de Células Escamosas/química , Reações Cruzadas , Feminino , Doença de Hodgkin/metabolismo , Humanos , Imuno-Histoquímica/métodos , Masculino , Espectrometria de Massas , Neoplasias Bucais/química , Seminoma/química , Família de Moléculas de Sinalização da Ativação Linfocitária , Testículo/química
7.
Histopathology ; 46(4): 442-50, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15810956

RESUMO

AIMS: Bone marrow is the major site of B-cell generation in humans. While in early childhood a high number of B-cell precursors is found in the bone marrow, only very few such cells are usually detectable in adult bone marrow. To assess the number of immature B cells present after haematopoietic cell transplantation the number of terminal deoxynucleotidyl transferase (TdT)-positive cells in regenerating bone marrow of adult patients was analysed. METHODS AND RESULTS: Bone marrow biopsy specimens were analysed from patients after allogeneic bone marrow transplantation (BMT; n = 14) or stem cell transplantation (SCT; n = 25) and autologous BMT (n = 9). Specimens from 11 untransplanted adult patients and 11 infants were also studied, as negative and positive controls, respectively. Immunohistochemistry was performed on paraffin-embedded bone marrow biopsy sections using TdT as a marker of lymphoid progenitors. Immunoreactivity for CD79a, CD20 and CD10 was used to confirm their B-cell origin. Using computer-assisted automated image analysis we quantitatively assessed the TdT+ cells present. We found a significant increase in the numbers of B-cell precursors in the bone marrow after allogeneic and autologous BMT/SCT compared with adult controls (P = 0.022). To analyse this in detail, we followed some patients after allogeneic BMT/SCT for up to 1445 days, when a marked B-cell increase was still detectable. However, the median number of TdT+ B cells after BMT/SCT was significantly lower than the number of equivalent B cells in infantile bone marrow biopsy specimens (P < 0.001). CONCLUSIONS: Bone marrow of adult patients after BMT/SCT is capable of initiating vigorous precursor B-cell generation, which is not seen in untransplanted adults. However, the increase of immature B cells was variable in our study. Only in two young adult patients did it reach the magnitude of B-cell generation seen in infantile bone marrow where immunocompetent B cells are produced normally. A marked increase in number of immature B cells post-transplant may mimic B-cell acute lymphoblastic leukaemia (B-ALL). This is a potential problem in patients transplanted for B-ALL itself. Since reactive and neoplastic B-cell precursors share the same immunophenotype in paraffin-embedded tissue, additional tools, particularly molecular techniques, may have to be employed to establish the correct diagnosis.


Assuntos
Linfócitos B/citologia , Transplante de Medula Óssea , DNA Nucleotidilexotransferase/sangue , Transplante de Células-Tronco de Sangue Periférico , Adulto , Idoso , Biópsia , Medula Óssea/patologia , Criança , Pré-Escolar , Humanos , Lactente , Leucemia/patologia , Leucemia/terapia , Contagem de Linfócitos , Linfoma/patologia , Linfoma/terapia , Linfopoese , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/terapia , Fatores de Tempo , Transplante Homólogo
8.
Pathologe ; 25(1): 56-62, 2004 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-14767613

RESUMO

Undifferentiated salivary gland carcinomas may be divided into small cell and large cell types. Among large cell undifferentiated carcinomas, lymphoepithelial carcinomas have to be distinguished, the latter of which are endemic in the Arctic regions and southern China where virtually all cases of these tumors are associated with the Epstein-Barr virus (EBV). Association with EBV may also be observed in sporadic cases, and detection of EBV gene products may aid their diagnosis. Immunohistology may be employed to resolve the differential diagnosis of undifferentiated salivary gland carcinomas, comprising malignant lymphomas, amelanotic melanomas, Merkel cell carcinomas, and adenoid cystic carcinomas, in particular in small biopsy materials. Because of the rarity of undifferentiated salivary gland carcinomas, the differential diagnosis should always include metastases of undifferentiated carcinomas arising at other primary sites, particularly when expressing the thyroid transcription factor-1 (TTF-1).


Assuntos
Neoplasias Epiteliais e Glandulares/patologia , Neoplasias das Glândulas Salivares/patologia , Diferenciação Celular , Herpesvirus Humano 4/isolamento & purificação , Humanos , Neoplasias Epiteliais e Glandulares/virologia , Neoplasias das Glândulas Salivares/virologia
9.
J Pathol ; 202(1): 34-40, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14694519

RESUMO

Cytokines and chemokines including interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) are secreted in response to major abdominal operations. The aim of this study was to identify the peritoneal cells that produce IL-6 and MCP-1. Samples of peritoneal tissue were taken from patients at the beginning and end of major abdominal operations. The samples were incubated in culture medium on microtitre plates for 5 h. The concentrations of IL-6 and MCP-1 were measured in culture supernatants by enzyme-linked immunosorbent assay (ELISA). In paraffin sections, cells that expressed IL-6 or MCP-1 were identified by combined in situ hybridization and immunohistochemistry. Antibodies against CD68, CD34, actin, and calretinin were included in these experiments. The median production of IL-6 increased significantly from 6256 pg/ml at the start of the operation to 20,000 pg/ml at the end. Production of MCP-1 rose from 7700 pg/ml to 11,820 pg/ml. IL-6 mRNA was mainly confined to endothelial cells. MCP-1 was expressed by a broader range of cells, consisting of actin-positive smooth muscle cells and endothelial cells, fibroblast-like cells, as well as occasional macrophages and mesothelial cells. Peritoneal endothelial cells contribute to the transient increase in concentrations of IL-6 in the circulation after surgical trauma. Recruitment of monocytes to the site of the trauma seems to be mainly effected by actin-positive smooth muscle cells and endothelial cells.


Assuntos
Quimiocina CCL2/análise , Interleucina-6/análise , Peritônio/metabolismo , Adulto , Idoso , Células Cultivadas , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Células Epiteliais/metabolismo , Feminino , Fibroblastos/metabolismo , Expressão Gênica/genética , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Liso/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Peritônio/patologia , Peritônio/cirurgia , Fenótipo , RNA/análise , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
10.
J Pathol ; 201(2): 312-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14517849

RESUMO

Epstein-Barr virus (EBV) is associated with several lymphoid and epithelial human malignancies. The latter include gastric adenocarcinomas, while sporadic colorectal adenocarcinomas (CRCs) have been reported to be EBV-negative. Recently, increased numbers of EBV-infected B lymphocytes have been detected in intestinal mucosal samples affected by ulcerative colitis (UC) and, to a lesser extent, Crohn's disease (CD). Both CRC and colorectal non-Hodgkin's lymphoma (NHL) are recognized complications of inflammatory bowel disease (IBD), but it is unclear to what extent EBV contributes to the development of these neoplasms. Seventeen cases of IBD-associated CRC and nine cases of IBD-associated colorectal NHL were therefore studied for the presence of EBV by in situ hybridization. EBV-positive cases were further studied for the expression of the EBV-encoded nuclear antigen (EBNA) 2 and the latent membrane protein (LMP) 1 of EBV by immunohistochemistry. Four out of seven cases of colorectal NHL associated with UC were shown to be EBV-positive. In addition, two of two colorectal NHLs developing in patients with CD were EBV-positive. Of the EBV-positive lymphomas, three displayed a pattern of EBV latent gene expression consistent with type I latency (EBNA2(-)/LMP1(-)), two a type II pattern (EBNA2(-)/LMP1(+)), and one a type III pattern (EBNA2(+)/LMP1(+)). These findings suggest that EBV infection is involved in the pathogenesis of a proportion of colorectal NHLs developing in IBD. Iatrogenic immunosuppression may contribute to the development of these lymphomas. By contrast, all 17 IBD-associated CRCs were EBV-negative, including a case of CRC occurring synchronously with an EBV-positive NHL. In conjunction with previous reports on sporadic CRCs, this suggests that EBV is not involved in the pathogenesis of CRC.


Assuntos
Neoplasias Colorretais/virologia , Herpesvirus Humano 4/isolamento & purificação , Doenças Inflamatórias Intestinais/virologia , Linfoma de Células B/virologia , Adenocarcinoma/complicações , Adenocarcinoma/virologia , Adulto , Idoso , Colite Ulcerativa/complicações , Colite Ulcerativa/virologia , Colo , Neoplasias Colorretais/complicações , Doença de Crohn/complicações , Doença de Crohn/virologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/complicações , Mucosa Intestinal/virologia , Linfoma de Células B/complicações , Masculino , Pessoa de Meia-Idade
11.
Mol Pathol ; 56(3): 156-61, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12782762

RESUMO

AIMS: Epstein-Barr virus (EBV) immortalises B cells in vitro and is associated with several malignancies. Most phenotypic effects of EBV are mediated by latent membrane protein 1 (LMP1), which interacts with tumour necrosis factor receptor associated factors (TRAFs) to activate NF-kappaB. This study examines TRAF1 and LMP1 expression in EBV associated lymphoproliferations. METHODS: TRAF1 expression was investigated in 26 Hodgkin lymphomas (HL; 18 EBV+, eight EBV-), seven EBV+ Burkitt lymphomas (BL), two infectious mononucleosis (IM) tonsils, and lymphoreticular tissue from eight chronic virus carriers. Seven anaplastic large cell lymphomas and 10 follicular B cell lymphomas were also studied. Colocalisation of TRAF1 and LMP1 was studied by immunofluorescent double labelling and confocal laser microscopy. RESULTS: TRAF1 colocalises with LMP1 in EBV infected cells in IM. EBV positive lymphocytes from chronic virus carriers were negative for TRAF1 and LMP1. In HL biopsies, TRAF1 was strongly expressed independently of EBV status, whereas all BL cases were TRAF1-. In EBV+ HL cases, TRAF1 colocalised with LMP1. Eight of 10 follicular lymphomas expressed TRAF1 in centroblast-like cells. Four of seven anaplastic large cell lymphomas weakly expressed TRAF1. CONCLUSIONS: These results suggest that in non-neoplastic lymphocytes, TRAF1 expression is dependent on the presence of LMP1, and that in IM B cells in vivo, LMP1 associated signalling pathways are active. In HL, TRAF1 is expressed independently of EBV status, probably because of constitutive NF-kappaB activation. The function of TRAF1 in HL remains to be determined.


Assuntos
Infecções por Vírus Epstein-Barr/metabolismo , Doença de Hodgkin/metabolismo , Proteínas/metabolismo , Proteínas da Matriz Viral/metabolismo , Portador Sadio , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/virologia , Humanos , Técnicas Imunoenzimáticas , Proteínas de Neoplasias/metabolismo , Fator 1 Associado a Receptor de TNF , Células Tumorais Cultivadas
12.
Onkologie ; 26(1): 12-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12624512

RESUMO

PURPOSE: Aim of this study was to retrospectively evaluate patterns of failure, results, and prognostic factors for patients with nasopharyngeal cancer (NPC) following radiotherapy (RT) with and without concurrent chemotherapy (RCT). PATIENTS AND METHODS: Between 1978 and 1999, a total of 101 patients with NPC were treated in our hospital, of whom 53 received external megavoltage RT alone with a median total dose of 76 Gy (1978-1988), and 48 patients had RCT (1989-1999). For RCT a combination of 5-FU and cisplatin was used together with a median total dose of 72 Gy. Patterns of relapse, survival rates and toxicity as well as prognostic factors were evaluated retrospectively. RESULTS: RCT was associated with a marked reduction in distant metastases: 6/48 (13%) vs. 17/53 (32%) after RT alone. Locoregional tumor persistence was only marginally lower with RCT: 10/48 (21%) vs. 17/53 (32%) following RT. Patients with RCT demonstrated a survival advantage compared to those with RT alone (5-year overall survival (OS): 64% vs. 44%, p = 0.1). OS, disease-specific survival and locoregional control rates were 53, 57, and 78% at 5 years and 47, 51 and 78% at 10 years, respectively. OS was significantly affected by histology (p = 0.007), the patients' age (p = 0.009) and gender (p = 0.01). CONCLUSION: This retrospective study provides further evidence that both reduction of distant metastasis and enhanced local tumor control by combined radiochemotherapy may be associated with improved survival rates in NPC compared to radiation alone. Concurrent RCT is therefore considered the preferable treatment option, however, confirmation in randomized trials is still warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Alta Energia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida , Falha de Tratamento
13.
Endoscopy ; 33(12): 1065-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11740648

RESUMO

Pancreatic endotherapy is frequently performed in patients with chronic pancreatitis and stenoses of the main pancreatic duct. In a patient with long-standing chronic pancreatitis and treatment with pancreatic stents, metastatic pancreatic head carcinoma was suspected because of infiltration of the neighboring organs and hepatic lesions. Ultrasound-guided aspiration of one liver lesion revealed grains typical for actinomycosis. In the light of this case, an extracted pancreatic stent was microbiologically investigated for actinomycetes in another patient who had a suspicious lesion of the pancreatic head. Microbiological examination of the extracted pancreatic stent revealed colonization by Actinomyces meyeri, Klebsiella oxytoca, and mixed cultures of anaerobic and saprophytic Gram-positive bacteria. In the following weeks, she developed a septic clinical picture with multiple abscesses of the liver. Actinomyces meyeri, Corynebacterium species, Candida and Enterococcae were cultivated in the aspirates. It seems possible, that treatment with pancreatic stents could have caused invasion of actinomycetes into the parenchyma of the pancreas, which was already harmed by the chronic inflammation, followed by the typical infiltrative growth and hematologic or biliary seeding into the liver.


Assuntos
Actinomicose/etiologia , Abscesso Hepático/etiologia , Pancreatite/terapia , Stents/efeitos adversos , Doença Crônica , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/patologia , Pessoa de Meia-Idade , Sucção , Tomografia Computadorizada por Raios X , Ultrassonografia
14.
Am J Pathol ; 159(5): 1613-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11696421

RESUMO

At the invasion front of well-differentiated colorectal adenocarcinomas, the oncogene beta-catenin is found in the nuclear compartment of tumor cells. Under these conditions, beta-catenin can function as a transcription factor and thus activate target genes. One of these target genes, cyclin D1, is known to induce proliferation. However, invasion front of well-differentiated colorectal adenocarcinomas are known to be zones of low proliferation and express the cell cycle inhibitor p16INK4A. Therefore, we investigated the expression profiles of nuclear beta-catenin, cyclin D1, p16INK4A, and the Ki-67 antigen, a marker for proliferation, in serial sections of well-differentiated colorectal adenocarcinomas. Invasion fronts with nuclear beta-catenin were compared with areas from central parts of the tumors without nuclear beta-catenin, for the expression of cyclin D1, p16INK4A, and Ki-67. It was observed that expression of nuclear beta-catenin, cyclin D1, and p16INK4A at the invasion front are significantly correlated. Such areas exhibit low Ki-67 expression indicating a low rate of proliferation. Thus, in colorectal carcinogenesis the function of beta-catenin and its target gene cyclin D1 does not appear to be the induction of tumor cell proliferation. In particular, the function of cyclin D1 should be reconsidered in view of these observations.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Ciclinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Transativadores , Idoso , Idoso de 80 Anos ou mais , Divisão Celular , Núcleo Celular/metabolismo , Ciclina D , Feminino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , beta Catenina
15.
Microsc Res Tech ; 53(6): 409-13, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11525258

RESUMO

The association of Epstein-Barr virus (EBV) with a proportion of gastric carcinomas is well established. The role of EBV in conditions predisposing to carcinoma such as chronic gastritis has remained undefined, however. We used in situ hybridization with radioactive and nonradioactive single-stranded RNA probes specific for the EBV small latent nuclear transcripts, EBER1 and EBER2, to analyze biopsy specimens from 242 patients with mild to severe chronic gastritis of Sydney classification types A, B, and C. A small number of EBV infected lymphocytes was detected in only nine cases, even in biopsies investigated with radioactive probes. Labeling of epithelial or stromal cells was not observed. The paucity of latently EBV-infected cells in chronic gastritis biopsies differs from the previously reported higher prevalence of virus carrying cells in inflammatory conditions at other sites of the gastrointestinal tract. These findings argue against a direct involvement of EBV in the pathogenesis of chronic gastritis. The low prevalence of EBV-positive cells suggests that local factors do not favor the entry and retention of circulating EBV-infected lymphocytes in gastric mucosa. Moreover, our findings indicate that EBV infection of gastric epithelial cells is not an early event in gastric carcinogenesis.


Assuntos
Mucosa Gástrica/virologia , Gastrite/virologia , Herpesvirus Humano 4/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , RNA Viral/genética
16.
Int J Exp Pathol ; 82(3): 149-70, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11488990

RESUMO

The Epstein-Barr virus (EBV) is a herpes virus which establishes a life-long persistent infection in over 90% of the human adult population world-wide. Based on its association with a variety of lymphoid and epithelial malignancies, EBV has been classified as a group 1 carcinogen by the International Agency for Research on Cancer. In this article we discuss the evidence supporting an aetiological role for EBV in the pathogenesis of human tumours. The biology of EBV infection will be described with special emphasis on viral transforming gene products. A brief survey of EBV-associated tumours is followed by a discussion of specific problems. Evidence is presented which suggests that failures of the EBV-specific immunity may play a role in the pathogenesis of EBV-associated tumours also in patients without clinically manifest immunodeficiencies. Finally, the timing of EBV infection in the pathogenesis of virus-associated malignancies is discussed. There is good evidence that EBV infection precedes expansion of the malignant cell populations in some virus-associated tumours. However, this is clearly not always the case and for some of these tumours there are indications that clonal genetic alterations may occur prior to EBV infection. Thus, whilst there is good evidence to suggest that EBV is a human carcinogen, its precise role(s) in the development of virus-associated human tumours requires clarification.


Assuntos
Herpesvirus Humano 4/patogenicidade , Proteínas Oncogênicas Virais/metabolismo , Linfoma de Burkitt/virologia , Doença de Hodgkin/virologia , Humanos , Mononucleose Infecciosa/virologia , Linfoma/virologia , Linfoma não Hodgkin/virologia , Transtornos Linfoproliferativos/virologia , Neoplasias Nasofaríngeas/virologia , Infecções Tumorais por Vírus/genética , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/metabolismo
17.
Laryngorhinootologie ; 80(7): 410-5, 2001 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-11488153

RESUMO

BACKGROUND: The term "midline granuloma syndrome" (MGS) is a clinical description of a broad spectrum of diseases, which are characterised by aggressive and progressive destruction of mucosa and adjacent structures of the midface and upper aerodigestive tract. After exclusion of granulomatous infections, rare granulomatous diseases and epithelial neoplasias, the differential diagnosis includes the following entities: Wegener's granulomatosis (WG), malignant lymphoma and idiopathic midline destructive disease (IMDD). Today there are doubts about the existence of IMDD. After exclusion of WG nearly all remaining cases presenting as MGS are peripheral sinonasal angiocentric T- and/or NK-cell lymphomas, which show a close association to Epstein-Barr virus infection and now are recognised as a special clinicopathological entity. The natural history of these lymphomas is characterised through a rapidly progressive course with a poor prognosis. PATIENT: A case of a 35-year-old male patient with an angiocentric nasal T/NK-cell lymphoma, which involved the left lacrimal cyst, the left maxillar and ethmoid sinus as well as the soft and hard palates, is presented. First clinical signs and symptoms were similar to chronic-recurrent sinusitis. For almost two years the patient was treated with systemic corticoids for suspected limited Wegener's granulomatosis. The patient underwent sinus surgery for pansinusitis three times. After development of midline destructive disease the diagnosis of angiocentric lymphoma was established. RESULTS: Soon after the diagnosis a combination high-dose radiochemotherapy was performed. The patient died only 3 months later because of multiorgan failure. CONCLUSIONS: Because of its poor prognosis the angiocentric nasal NK/T-cell lymphoma should included early into the differential diagnosis of the midline granuloma syndrome. Correct biopsy technic and in situ hybridization of EBV can be important for an early diagnosis. Therapy should be aggressive and consists of high-dose radiotherapy, which is most important to reach local tumor control, and combination chemotherapy, the use of which is presently in discussion.


Assuntos
Granuloma Letal da Linha Média/diagnóstico , Linfoma de Células T/diagnóstico , Linfoma de Células T/patologia , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/patologia , Adulto , Biópsia , Diagnóstico Diferencial , Granuloma Letal da Linha Média/diagnóstico por imagem , Granuloma Letal da Linha Média/mortalidade , Humanos , Linfoma de Células T/mortalidade , Imageamento por Ressonância Magnética , Masculino , Neoplasias Nasais/mortalidade , Prognóstico , Fatores de Tempo , Tomografia Computadorizada por Raios X
18.
Mol Pathol ; 54(4): 264-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11477143

RESUMO

AIMS: Post-transplant lymphoproliferative disease (PTLD) is an important and serious complication in transplant patients. Recent studies have suggested that quantitative assessment of Epstein-Barr virus (EBV) infection in transplant patients might help to identify those at risk of developing PTLD. Therefore, tonsils from paediatric liver transplant recipients were studied for evidence of EBV infection. METHODS: Tonsils were studied by in situ hybridisation for the detection of the small EBV encoded nuclear RNAs (EBERs). The phenotype of EBV infected cells was determined by double labelling in situ hybridisation and immunohistochemistry. The expression of viral latent and lytic antigens was determined by immunohistochemistry. Tonsils from patients without known immune defects were studied as controls. RESULTS: Tonsils from transplant patients showed pronounced follicular hyperplasia and minor paracortical hyperplasia. In situ hybridisation revealed variable numbers of EBV infected B cells in the tonsils from transplant patients (range, 2-1000/0.5 cm(2); mean, 434/0.5 cm(2); median, 105/0.5 cm(2)). Lower numbers were detected in the control tonsils (range, 1-200/0.5 cm(2); mean, 47/0.5 cm(2); median, 9/0.5 cm(2)). The latent membrane protein 1 (LMP1) of EBV was not detected and there were only rare cells in two cases showing expression of the EBV encoded nuclear antigen 2 (EBNA2). There was no evidence of lytic infection. None of the patients developed PTLD within a follow up period of up to five years. CONCLUSIONS: These data indicate that tonsillar enlargement in paediatric liver transplant patients does not necessarily imply a diagnosis of PTLD. Furthermore, the presence of increased numbers of EBV infected cells in tonsils from liver transplant recipients by itself does not indicate an increased risk of developing PTLD.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/genética , Transplante de Fígado , Tonsila Palatina/virologia , RNA Viral/análise , Antígenos Virais/análise , Linfócitos B/virologia , Criança , Pré-Escolar , Feminino , Herpesvirus Humano 4/imunologia , Humanos , Hiperplasia , Imuno-Histoquímica , Hibridização In Situ , Lactente , Transtornos Linfoproliferativos/diagnóstico , Masculino , Tonsila Palatina/patologia , Período Pós-Operatório , Tonsilectomia
19.
Liver ; 21(4): 260-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11454189

RESUMO

BACKGROUND/AIM: Quantitative tests of liver function may be superior to conventional tests to assess the prognosis of patients with liver diseases. There are insufficient data from quantitative testing of liver function (QTLF) for patients with chronic hepatitis B and C, particularly with regard to fibrosis. Therefore, we applied a broad panel of QTLF to these patients. METHODS: Three hundred and sixty-seven consecutive patients with chronic hepatitis B or C underwent liver biopsy and QTLF, which included tests for hepatic metabolism (aminopyrine breath test, galactose elimination capacity) and for hepatic perfusion (sorbitol clearance, indocyanine green clearance). QTLF values were correlated with liver histology (grading and staging for inflammation and fibrosis) and Child-Pugh classification for liver cirrhosis. RESULTS: In patients with no and moderate fibrosis, metabolic liver function was significantly decreased, whereas hepatic perfusion remained normal. Severe fibrosis and cirrhosis showed a significant decline in all QTLFs. Hepatic inflammation only reduced metabolic liver function, irrespective of the inflammatory grade. Viral etiology and HCV genotypes did not change QTLF. CONCLUSIONS: In summary, viral damage compromises hepatic metabolism before perfusion. Therefore, tests of metabolic liver function (aminopyrine breath test, galactose elimination capacity) should be useful to search for drugs that restore liver function in viral hepatitis irrespective of the fibrosis stage.


Assuntos
Hepatite B Crônica/fisiopatologia , Hepatite C Crônica/fisiopatologia , Cirrose Hepática/fisiopatologia , Adulto , Feminino , Hepatite B Crônica/patologia , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade
20.
J Pathol ; 194(2): 145-51, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11400141

RESUMO

Nasopharyngeal carcinoma (NPC) and Hodgkin's disease (HD) are characterized by their association with Epstein-Barr virus (EBV) and the presence of an intense lymphoid stroma, consisting of T lymphocytes and other reactive cells. In both entities, the tumour cells express viral proteins known to provide target epitopes for cytotoxic T-cells (CTLs), yet in vivo, the tumour cells appear to escape CTL recognition. A comparative in situ hybridization study of cytokine and chemokine gene expression in NPC and HD has been undertaken, focusing on cytokines which are known to be inducible by EBV in vitro. Hodgkin and Reed-Sternberg (HRS) cells expressed interleukin (IL)-6, IL-8, and IL-10, and the thymus and activation regulated chemokine (TARC) in 15/22, 0/22, 5/22, and 16/21 cases, respectively. In NPC, the epithelial tumour cells showed expression of IL-6 in 3/43 cases and of IL-8 in 2/40 cases. There was no detectable expression of IL-10 and TARC in these cases. These data confirm that HRS cells frequently express cytokine and chemokine genes and suggest that this may enable HRS cells to modulate the immune response in their microenvironment and to escape CTL detection. In contrast, NPC tumour cells show only rare expression of IL-6 and IL-8 and no detectable expression of IL-10 and TARC. Thus, the results suggest that the mechanisms employed by the EBV-positive tumour cells to escape immune recognition and destruction differ between HD and NPC.


Assuntos
Carcinoma/virologia , Citocinas/genética , Infecções por Vírus Epstein-Barr/genética , Doença de Hodgkin/virologia , Neoplasias Nasofaríngeas/virologia , RNA Mensageiro/análise , Carcinoma/genética , Carcinoma/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/virologia , Quimiocina CCL17 , Quimiocinas CC/análise , Quimiocinas CC/genética , Infecções por Vírus Epstein-Barr/imunologia , Expressão Gênica , Doença de Hodgkin/genética , Doença de Hodgkin/imunologia , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Interleucina-10/análise , Interleucina-10/genética , Interleucina-6/análise , Interleucina-6/genética , Interleucina-8/análise , Interleucina-8/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/imunologia , Células de Reed-Sternberg/imunologia
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