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1.
Z Gastroenterol ; 44(5): 387-90, 2006 May.
Artículo en Alemán | MEDLINE | ID: mdl-16688655

RESUMEN

Epstein-Barr virus (EBV) infection has a prevalence of 90 % and is - depending on the immune status of the host - associated with a broad spectrum of clinical manifestations. By presenting a case report we would like to demonstrate an unusual clinical course of a primary infection with EBV in an elderly patient. A 77-year-old patient was admitted to hospital in reduced health condition because of a persisting bronchopulmonary infection with B symptoms. The patient had already been treated with antibiotics. Because of elevated liver enzymes, a liver biopsy was performed. Histopathology revealed moderate acute hepatitis with cholangitis und endothelialitis, pointing to an EBV-induced hepatitis. Serological examinations confirmed the diagnosis, revealing a primary infection with positive EBV VCA IgM and IgG. EBV PCR of the liver tissue was positive, viral genome could be demonstrated within lymphocytes. A short period later the patient was discharged to reconvalescence. This case report demonstrates an unusual primary infection with EBV at the age of 77 with atypical clinical symptoms and hepatitis. The relevance of EBV in the differential diagnosis of atypical infectious diseases with hepatitis of unknown aetiology is strengthened on taking data reports from the literature into consideration.


Asunto(s)
Infecciones por Virus de Epstein-Barr/diagnóstico , Hepatitis Viral Humana/diagnóstico , Anciano , Conductos Biliares Intrahepáticos/patología , Conductos Biliares Intrahepáticos/virología , Colangitis/diagnóstico , Colangitis/patología , Colangitis/virología , Diagnóstico Diferencial , Endotelio Vascular/patología , Endotelio Vascular/virología , Infecciones por Virus de Epstein-Barr/patología , Infecciones por Virus de Epstein-Barr/virología , Hepatitis Viral Humana/patología , Hepatitis Viral Humana/virología , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Hibridación in Situ , Hígado/patología , Hígado/virología , Pruebas de Función Hepática , Linfocitos/patología , Linfocitos/virología , Masculino , Reacción en Cadena de la Polimerasa
3.
Eur J Cancer ; 35(1): 117-24, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10211099

RESUMEN

The membrane-bound complement inhibitors CD46 (membrane cofactor protein), CD55 (decay-accelerating factor) and CD59 (protectin) protect tumour cells against lysis by activated complement. In this study, a total of 14 (3 gastric, 3 colonic and 8 pancreatic) gastrointestinal tumour cell lines were examined for the expression of CD46, CD55 and CD59 with respect to the regulatory efficacy of interferon-gamma (IFN-gamma). The effects of IFN-gamma on mRNA and protein expression levels of CD46, CD55 and CD59 were evaluated by Northern blot hybridisation, RT-PCR, flow cytometry and immunostaining. In unstimulated cell lines, CD46 and CD59 transcripts were expressed at comparable levels, whereas the basal expression of CD55 mRNA was heterogeneous. The complement inhibitor proteins were detected in all cell lines using specific antibodies. Additional immunohistochemical stainings of gastrointestinal tissue specimens supported these findings. IFN-gamma evoked a weak induction of certain transcripts in a subset of the cell lines. Upregulation of protein expression was only observed in HT29 cells for CD55 and CD59 and was accompanied by a marked increase of the corresponding transcripts. We conclude that membrane-bound complement inhibitors are broadly expressed in gastrointestinal tumour cells and vary in their susceptibility to IFN-gamma. Thus, they may be involved in tumour escape mechanisms in gastric, pancreatic and colorectal cancer.


Asunto(s)
Antígenos CD/metabolismo , Antígenos CD55/metabolismo , Antígenos CD59/metabolismo , Proteínas Inactivadoras de Complemento/metabolismo , Neoplasias Gastrointestinales/inmunología , Interferón gamma/farmacología , Glicoproteínas de Membrana/metabolismo , Northern Blotting , Southern Blotting , Citometría de Flujo , Humanos , Proteína Cofactora de Membrana , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
4.
Br J Cancer ; 77(4): 588-94, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9484816

RESUMEN

Protein expression of the putative tumour-suppressor gene DCC on chromosome 18q was evaluated in a panel of 16 matched colorectal cancer and normal colonic tissue samples together with DCC mRNA expression and allelic deletions (loss of heterozygosity, LOH). Determined by a polymerase chain reaction (PCR)-LOH assay, 12 of the 16 (75%) cases were informative with LOH occurring in 2 of the 12 cases. For DCC mRNA, transcripts could be detected in all analysed normal tissues (eight out of eight) by RT-PCR, whereas 6 of the 15 tumours were negative. DCC protein expression, investigated by immunohistochemistry using the monoclonal antibody 15041 A directed against the intracellular domain, was homogeneously positive in all normal tissue samples. In tumour tissues, no DCC protein was seen in 11 out of 16 samples (69%). For the DCC codon 201, we found a loss of a wild-type codon sequence caused by mutation or LOH in at least 8 out of 15 cases (53%) compared with the corresponding normal tissue. DCC protein expression was undetectable in eight of the nine tumours missing both wild-type codons. Only one of the five tumours with retained DCC protein expression had no detectable wild-type codon 201. In addition, 9 out of 15 normal tissue specimens were mutated in codon 201. In two out of three cases with homozygous wild-type codons in peripheral blood lymphocyte (PBL) DNA, mutations were already observed in the tumour adjacent normal colonic mucosa. We conclude that DCC immunostaining should be introduced in the clinicopathological routine because of its strong correlation with the known prognostic markers 18q LOH and mutation of codon 201.


Asunto(s)
Moléculas de Adhesión Celular/análisis , Neoplasias Colorrectales/química , Proteínas de Neoplasias/análisis , Proteínas Supresoras de Tumor , Southern Blotting , Moléculas de Adhesión Celular/genética , Codón/genética , Neoplasias Colorrectales/genética , Receptor DCC , Análisis Mutacional de ADN , Genes Supresores de Tumor , Humanos , Inmunohistoquímica , Pérdida de Heterocigocidad , Proteínas de Neoplasias/genética , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN Neoplásico/análisis , Receptores de Superficie Celular
5.
Virchows Arch ; 426(4): 375-84, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7599790

RESUMEN

Two new cell lines from stomach cancers and one from a pancreatic carcinoma are presented. MZ-GC-1 was established from a hepatic metastasis of a well differentiated gastric adenocarcinoma. MZ-GC-2 was derived from ascites induced by a poorly differentiated gastric adenocarcinoma. MZ-PC-1 originated from the pleural effusion of a moderately well differentiated pancreatic ductal adenocarcinoma. MZ-GC-1 cells were adherent and partially polarized, connected tightly via desmosomes. In contrast MZ-GC-2 cells consisted of slightly adherent or floating subpopulations and displayed no desmosomes. MZ-PC-1 cells were adherent and showed polarized growth, connected by apical junctional complexes. Cell doubling times were 7 days for MZ-GC-1 and 45 h for MZ-GC-2 and MZ-PC-1 cells. MZ-GC-2 and MZ-PC-1 gave rise to nude mouse tumours, resembling the original lesions. Chromosome analysis of the cell lines revealed a high range of numerical abnormalities. Each cell line had cytokeratin patterns fitting well to typical in vivo patterns. Furthermore the cell lines expressed a panel of antigens typical for gastrointestinal epithelia. Unique for MZ-PC-1 were high amounts of secreted Ca19-9. gamma-Interferon enhanced HLA-class I antigens up to twofold and induced ICAM-1 expression on each cell line. HLA-class II antigens were differentially enhanced by gamma-interferon. Due to their distinct characteristics the three tumour cell lines may be useful models in the investigation of the cell biology and immunogenicity of gastrointestinal tumours.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Pancreáticas/patología , Neoplasias Gástricas/patología , Antígenos de Superficie/análisis , Biomarcadores de Tumor/análisis , Diferenciación Celular , División Celular , Línea Celular Transformada , Epitelio/inmunología , Epitelio/patología , Humanos , Neoplasias Hepáticas/patología , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Metástasis de la Neoplasia/patología
7.
Int J Cancer ; 55(5): 857-64, 1993 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-7503962

RESUMEN

Mouse monoclonal antibody Pa-G-14 detects Exo-1, an antigen whose expression is regulated in the processes of epithelial-cell differentiation and transformation. The epitope recognized by Pa-G-14 is present both in glycosphingolipids and in mucin glycoproteins. To characterize the specificity of Pa-G-14, immuno-thin-layer chromatography, biochemical, and enzymatic treatment of glycosphingolipid extracts from human pancreas were used. The antibody bound to all blood-group-A substances; alpha GalNAc, but not fucose, was essential for reactivity. In ELISA, Pa-G-14 also reacted with ovine and bovine submaxillary mucins but not with porcine submaxillary mucin. Binding to ovine submaxillary mucin was resistant to neuraminidase treatment. In solid-phase absorption assays on synthetic carbohydrate structures, Pa-G-14 recognized broadly blood group A, Tn and sialyl-Tn. Using immuno-electron-microscopic techniques, reactivity with all Golgi cisternae and mucin droplets of mucous cells in ovine submaxillary gland was demonstrated. All these assays indicate that Pa-G-14 shows a novel specificity, since it binds blood group A, Tn and sialyl-Tn, the common structural feature of these epitopes being the presence of a terminal alpha GalNAc sugar unit.


Asunto(s)
Acetilgalactosamina/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/inmunología , Antígenos de Superficie/inmunología , Animales , Especificidad de Anticuerpos , Antígenos de Neoplasias/química , Antígenos de Superficie/química , Secuencia de Carbohidratos , Bovinos , Epítopos/análisis , Epítopos/química , Epítopos/inmunología , Glicoproteínas/inmunología , Glicoesfingolípidos/inmunología , Humanos , Ratones , Datos de Secuencia Molecular , Mucinas/inmunología , Páncreas/química , Ovinos , Glándula Submandibular/inmunología , Glándula Submandibular/ultraestructura
8.
J Immunol ; 151(5): 2521-8, 1993 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8360474

RESUMEN

Properdin plays an important regulatory role in the activation of the complement system. Here we report the biosynthesis of properdin in four different human T cell lines and in T cells purified from peripheral blood. Cell sorting experiments, in conjunction with Northern blotting, showed that both CD4- and CD8-bearing populations of T cells have the potential to synthesize properdin. The functional activity of properdin secreted from these T cell lines was determined in a hemolytic assay. In view of the numerous ways in which complement activation may influence cellular immune response, the present results indicate, for the first time, a possible interaction between the complement and the T cell system.


Asunto(s)
Activación de Complemento , Properdina/biosíntesis , Linfocitos T/inmunología , Adulto , Secuencia de Bases , Northern Blotting , Complejo CD3/análisis , Antígenos CD4/análisis , Antígenos CD8/análisis , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Properdina/genética , ARN Mensajero/análisis
9.
Eur J Cancer ; 29A(9): 1327-9, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8343279

RESUMEN

The clinical usefulness of immunoscintigraphy with the monoclonal anti-CEA (carcinoembryonic antigen) antibody BW431/26, directly labelled with 99m-Technetium in targeting colorectal carcinomas was investigated in 43 patients. In addition, tumour cell grading and CEA-expression were examined immunohistochemically. Best imaging results were obtained in pelvic tumour lesions (sensitivity 80%). Tumour grading correlated with radioimmunoimaging, well differentiated tumours being detectable at a higher rate (P = 0.09). Immunoscintigraphy preceded the findings of conventional diagnostic methods in 3 patients. In 4 cases immunoscintigraphy was decisive for patients management. Therefore, immunoscintigraphy with 99m-Technetium is valuable in directing patients management if conventional diagnostic methods remain undecisive.


Asunto(s)
Neoplasias del Colon/diagnóstico por imagen , Radioinmunodetección/métodos , Neoplasias del Recto/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Antígeno Carcinoembrionario/análisis , Antígeno Carcinoembrionario/inmunología , Diferenciación Celular , Neoplasias del Colon/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias del Recto/patología , Sensibilidad y Especificidad , Tecnecio
10.
Eur J Cancer ; 29A(12): 1723-8, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8398302

RESUMEN

EPM-1 (a high molecular weight glycoprotein) and EXO-1 (a carbohydrate epitope expressed on polar neutral glycolipids and mucins) are two developmental antigens of normal and neoplastic human epithelia and were characterised by monoclonal antibodies. Their distribution was investigated in normal and pathological human colorectal mucosa. In normal mucosa, EPM-1 and EXO-1 showed characteristic expression patterns. EPM-1 was differentially expressed along the crypt villus axis with maximum at the crypt basis. EXO-1 was present throughout the whole mucosa. The characteristic gradient of EPM-1 expression along the crypt axis in normal mucosa was no longer detectable in benign polyps. Intact gradient of EPM-1 staining discriminated between neoplastic changes of the benign adenomatous polyp and mucosal inflammation. Neoplastic mucosa in benign polyps and especially atypical glands in highly differentiated tumours showed essentially identical expression patterns. In colorectal carcinomas the overall reactivities for EPM-1 and EXO-1 were independently associated with the histopathological grade of tumour differentiation.


Asunto(s)
Antígenos de Neoplasias/análisis , Colon/inmunología , Neoplasias Colorrectales/inmunología , Glicoproteínas de Membrana/análisis , Recto/inmunología , Antígenos de Superficie/análisis , Colitis Ulcerosa/inmunología , Enfermedad de Crohn/inmunología , Humanos , Inmunohistoquímica , Mucosa Intestinal/inmunología , Pólipos Intestinales/inmunología
11.
Gut ; 32(12): 1508-13, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1685466

RESUMEN

The allele distribution of the Ha-ras gene on chromosome 11p was analysed by the restriction fragment length polymorphism of the enzymes Mspl/Hpall in 238 individuals. The investigation covered 116 patients with colorectal carcinoma and 122 patients with Crohn's disease, representing two patient populations with the same ethnic origin, one with a malignant and the other a benign disease of the same organ system. A total of 17 different alleles were detected belonging to the common, intermediate, and rare classes according to the original nomenclature of Ha-ras alleles. Patients with Crohn's disease showed no difference in the distribution of Ha-ras alleles when compared with expected frequencies. In patients with colorectal carcinoma, the frequency of rare alleles was significantly increased compared with the patients with Crohn's disease (chi 2 = 8.166; Fisher's exact test = 0.005) and with a reference population of 424 cancer free individuals (chi 2 = 49.312; Fisher's exact test = 0.000). Homozygosity was not detected for any rare allele. The occurrence of a rare Ha-ras allele was not linked to the location of the colorectal tumour. These results confirm the hypothesis that unique Ha-ras alleles represent an inherited factor which predisposes the development of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/genética , Enfermedad de Crohn/genética , Genes ras/genética , Alelos , Southern Blotting , Susceptibilidad a Enfermedades , Genotipo , Humanos , Polimorfismo de Longitud del Fragmento de Restricción
12.
Biochem Pharmacol ; 42(3): 521-8, 1991 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-1650214

RESUMEN

The Ah receptor regulates induction of cytochrome P450IA1 and mediates certain toxicities of polyhalogenated aromatics such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). It has been characterized previously in continuous cell lines, notably the mouse hepatoma line Hepa 1, the human squamous cell carcinoma line A431, and the human liver cell line Hep G2. The present work extends our knowledge of the Ah receptor in continuous human liver cell lines. Ah receptor can be detected in Mz-Hep-1, a hepatitis B virus-negative cell line derived from a Thorotrast-induced hepatocellular carcinoma. The mean concentration of Ah receptor in Mz-Hep-1 cells was 341 +/- 22 fmol/mg cytosol protein (mean +/- SEM, nine separate determinations). This is equivalent to approximately 30,000 sites per cell. The concentration of Ah receptor in Mz-Hep-1 cells is similar to that in Hepa 1 cells and approximately three times higher than that in Hep G2 cells. The Mz-Hep-1 Ah receptor sedimented in continuous sucrose gradients at approximately 9 S. Specificity of binding by [3H]TCDD was demonstrated by competitive binding of non-radiolabeled 2,3,7,8-tetrachlorodibenzofuran, 3-methylcholanthrene (MC), and dibenz[a,h]anthracene in 50-fold molar excess. Phenobarbital, which is not a substrate for P450IA1, did not compete with [3H]TCDD for binding to Mz-Hep-1 Ah receptor. Dexamethasone and estradiol also did not compete with [3H]TCDD for binding, suggesting non-identity of Ah receptor with glucocorticoid or estrogen receptor. In separate experiments, glucocorticoid receptor was identified in Mz-Hep-1 cells. By Scatchard plot analysis, the apparent equilibrium dissociation constant (Kd) for binding of [3H]TCDD to Mz-Hep-1 Ah receptor was estimated to be 4.4 nM, compared to 0.8 nM in Hepa 1 cells. By Woolf plot analysis the Kd was 5.4 nM, compared to 1.2 nM in Hepa 1 cells. The [3H]TCDD.Ah receptor complex extracted from nuclei of Mz-Hep-1 cells incubated with [3H]TCDD in culture at 37 degrees sedimented at approximately 6 S under conditions of high ionic strength. Aryl hydrocarbon hydroxylase (AHH) activity was detectable in Mz-Hep-1 cells after pretreatment with inducing chemicals. Mz-Hep-1 cells have the highest concentrations of Ah receptor in any continuous human liver cell line thus far investigated. The Mz-Hep-1 Ah receptor is similar physicochemically to that described in murine systems. AHH activity is inducible in Mz-Hep-1 cells.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/biosíntesis , Carcinoma Hepatocelular/metabolismo , Sistema Enzimático del Citocromo P-450/biosíntesis , Neoplasias Hepáticas/metabolismo , Dibenzodioxinas Policloradas/farmacología , Receptores de Droga/metabolismo , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Centrifugación por Gradiente de Densidad , Citosol/efectos de los fármacos , Citosol/metabolismo , Inducción Enzimática , Humanos , Ratones , Receptores de Hidrocarburo de Aril , Receptores de Droga/efectos de los fármacos , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo
14.
Laryngorhinootologie ; 70(6): 302-6, 1991 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-1872932

RESUMEN

Malignant melanomas of the mucous membranes are rare tumors. They make up about 10% of all malignant melanomas of the head and neck; 15 of the authors' cases are reviewed in this article. Six of these had neck lymph node metastasis when first diagnosed. The tumors were surgically removed in all patients. Thirteen patients developed at least one tumor recurrence, ten patients distant metastasis. Eight patients died of the tumor condition; the mean survival time of all patients was 33.4 months. While the tumors could be classified histologically into four types, this had no bearing on the course of the disease. In many cases, primary tumor and metastasis or recurrent tumor differed histologically. Melanin pigment was found in 13 tumors. Mucosal melanomas can be regarded as a discrete tumor entity because their biological behavior differs from that of malignant melanomas of the skin. However there are no morphological differences between the two tumor entities. Ophthalmological and dermatological examinations must be performed in all patients with mucosal melanoma to exclude metastasis of the skin or choroid melanoma.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Melanoma/patología , Adulto , Anciano , Senos Etmoidales , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Inmunohistoquímica , Masculino , Neoplasias del Seno Maxilar/patología , Melanoma/mortalidad , Persona de Mediana Edad , Membrana Mucosa , Neoplasias Nasales/patología , Neoplasias Orofaríngeas/patología , Neoplasias de los Senos Paranasales/patología
15.
Gastroenterology ; 100(5 Pt 1): 1338-44, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2013378

RESUMEN

Hematopoietic growth factors have recently been well characterized by complementary DNA cloning. For human epidermal growth factor, granulocyte-macrophage colony-stimulating factor recombinant proteins have been expressed in Escherichia coli. To reduce the toxic side effects of chemotherapy on the bone marrow, recombinant human granulocyte-macrophage colony-stimulating factor and recombinant human interleukin 3 were applied to patients suffering of gastrointestinal cancers. To determine the influence of recombinant human granulocyte-macrophage colony-stimulating factor and recombinant human interleukin 3 on human pancreas and gastric cancer cell cells in vitro, a sensitive microculture test system was established that allows precise quantification of proliferation. A more than twofold enhancement of proliferation was observed by interleukin 3 and granulocyte-macrophage colony-stimulating factor in two of two cell cultures derived from gastric carcinoma cells, while two of nine cultures from pancreas carcinoma cells have shown enhanced cell growth in the presence of recombinant human interleukin 3 or recombinant human granulocyte-macrophage colony-stimulating factor. In comparison, recombinant human epidermal growth factor increased cell growth in two of two gastric and in five of nine pancreas carcinoma cultures. In general, 1-10 ng/mL of the growth factors yielded the highest growth rate, but even 1-pg amounts produced increased cell growth. Expression of messenger RNA for granulocyte-macrophage colony-stimulating factor, interleukin 3, and the oncogene HER2/neu remained undetectable in all of the tested cell lines, while the various abundance of messenger RNA for the epidermal growth factor receptor was different in each cell line. The reported results imply that the hematopoietic growth factors interleukin 3 and granulocyte-macrophage colony-stimulating factor influence cellular growth of pancreas and gastric carcinoma cells by a paracrine mechanism and may possess a more general regulatory function than originally anticipated.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Interleucina-3/farmacología , Neoplasias Pancreáticas/patología , Neoplasias Gástricas/patología , Animales , División Celular/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Ratones , Neoplasias Pancreáticas/química , ARN Mensajero/análisis , Neoplasias Gástricas/química , Células Tumorales Cultivadas/efectos de los fármacos
16.
Cancer Res ; 50(23): 7668-76, 1990 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-2253212

RESUMEN

Exo-1, a polar neutral glycolipid, and EPM-1, a high molecular weight glycoprotein, are developmental antigens of human epithelial cells, initially described as components both on the cell surface and in secretions of gastrointestinal epithelial and respective tumors. In order to assess the biological significance of both antigens for epithelial cell differentiation and neoplastic transformation, their expression during human skin development and benign and malignant neoplasia was analyzed in fresh frozen tissue specimens of skin biopsies and of human epidermal keratinocytes growing in experimental model systems. Antigen expression was assessed immunohistochemically with specific monoclonal antibodies. During fetal development Exo-1 was temporarily expressed in intermediate cells but was absent in normal adult human skin. Exo-1 expression reemerged in neoplasias, both benign and malignant, but was restricted to spinous-like differentiated cells. Similarly, Exo-1 was not expressed in transplants of normal keratinocytes mimicking the normal epidermis but was clearly visible in differentiated areas of transplants of malignantly transformed keratinocytes. EPM-1 appeared first in basal epidermal cells in the second half of gestation and remained detectable in the stratum basale of adult skin. While squamous cell carcinomas continued to express EPM-1, it was not detectable in basal cell epitheliomas and in normal epidermis after invasion by neuroectodermal tumor cells. In experimental models, EPM-1 was present in the basal layers of normal human keratinocytes and of transformed keratinocytes with benign growth characteristics whenever a well stratified and keratinized epidermis-like epithelium had formed in transplants. In transformed keratinocytes with malignant growth behavior, EPM-1 was expressed irregularly, as in squamous cell carcinomas in situ. Thus, expression of Exo-1 is a marker for an early embryonic differentiation pathway of human keratinocytes and in adult tissue reveals abnormal differentiation associated with certain stages of hyperproliferation. EPM-1 expression is part of developmental programs and is influenced by microenvironmental interactions and alterations of tissue homeostasis.


Asunto(s)
Antígenos/biosíntesis , Desarrollo Embrionario y Fetal/inmunología , Queratinocitos/inmunología , Enfermedades de la Piel/inmunología , Antígenos de Superficie/biosíntesis , Diferenciación Celular/inmunología , Transformación Celular Neoplásica , Expresión Génica , Cabello/inmunología , Humanos , Hiperplasia/inmunología , Inmunohistoquímica , Psoriasis/inmunología , Glándulas Sebáceas/inmunología , Piel/inmunología , Neoplasias Cutáneas/inmunología , Transfección , Verrugas/inmunología
17.
Z Gastroenterol ; 28(12): 673-7, 1990 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-2087823

RESUMEN

In the last decade radioimmunoscintigraphy developed from an experimental approach to a clinically useful method. First promising results were obtained with Technetium-99m labelled murine monoclonal antibodies against carcinoembryonic antigen (CEA). Routine clinical application is restricted to colorectal carcinoma at the moment. Radioimmunoscintigraphy is recommended in case of recurring disease when conventional methods are ineffective or doubtful, especially in the pelvic region. The availability of monoclonal antibodies to new tumor-associated antigens will extend the spectrum to other gastrointestinal tumors. The possibility to generate recombinant humanized monoclonal antibodies and antibody fragments are encouraging new perspectives. These developments and the use of biological immune response modifiers to increase antigen expression could provide means to consider radioimmunotherapy of gastrointestinal cancers.


Asunto(s)
Anticuerpos Monoclonales , Antígeno Carcinoembrionario/inmunología , Neoplasias Colorrectales/diagnóstico por imagen , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos/inmunología , Neoplasias Colorrectales/inmunología , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tecnecio , Tomografía Computarizada de Emisión de Fotón Único/métodos
18.
Int J Cancer ; 44(1): 155-60, 1989 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-2744885

RESUMEN

Gangliosides appear to be important target molecules for immunological effector mechanisms on neuro-ectodermal tumors. Therefore in vitro studies were performed to examine whether ganglioside GD3, which is highly expressed on the cell surface of cultured human melanoma cells, is being shed into the culture medium. Measurable quantities of gangliosides GM3 and in particular GD3 were shed by the melanoma cells we have tested as detected on thin-layer chromatograms (TLC) stained with orcinol. Ganglioside GD3 was also evidenced by immunostaining with anti-GD3 MAb and by ELISA. The concentration of GD3 in the supernatant of human melanoma cells depended on the ganglioside pattern of the cell line. Cells containing high levels of GD3 shed large amounts, cells with low levels shed no detectable GD3. Ganglioside GD3 was detectable in sera, but no major quantitative differences were observed in sera of patients with GD3-positive tumors and normal controls. This points to a local accumulation of ganglioside GD3 at the tumor site.


Asunto(s)
Gangliósidos/análisis , Melanoma/análisis , Gangliósido G(M3)/análisis , Humanos , Células Tumorales Cultivadas
19.
Immun Infekt ; 17(1): 26-7, 1989 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-2925221

RESUMEN

Patients with B-cell lymphomas, gastrointestinal tumors and melanomas were treated in pilot and phase-I clinical studies with monoclonal antibodies directed to tumor-associated antigens in recent years. Side effects of this new treatment approach were minor. Tumor regressions were observed in all three groups of tumors.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Gastrointestinales/terapia , Linfoma/terapia , Melanoma/terapia , Humanos
20.
Cancer Res ; 48(12): 3454-60, 1988 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-3370642

RESUMEN

Gangliosides from benign and malignant melanomas and from normal skin of the fish genus Xiphophorus were isolated and analyzed by thin-layer chromatography. Individual ganglioside components were characterized by mapping according to their sialic acid content and by cleavage with neuraminidases. In all three tissues examined, sulfatide and the gangliosides NeuAc-GalCer (GM4), II3NeuAc-LacCer (GM3), II3NeuAc-GgOse3Cer (GM2), and II3(NeuAc)2-LacCer (GD3) were found. Ganglioside GD3 yielded a positive reaction, following immunoadsorption with mouse monoclonal antibody R24 on thin-layer plates. Two alkali-labile disialoganglioside species were specifically recognized by mouse monoclonal antibody D1.1, thus indicating the presence of O-acetyl-neuraminic acid residues. One of them, a major ganglioside component of the malignant melanoma, was identified as O-acetyl-GD3, since it could be converted to the R24-positive GD3 ganglioside after alkaline saponification. The other one appears to be restricted to the malignant tumor and represents a novel melanoma-associated ganglioside derivative. It was characterized as O-acetyl(NeuAc)2-nLc4Cer by exoglycosidase cleavage, by proving its neutral carbohydrate backbone as type II-chain lacto-series oligosaccharide using mouse monoclonal antibody 1B2, and by its cross-reaction with antibody R24 following alkaline treatment. Using antibody R24 and cryopreserved tissue sections of both benign and malignant amelanotic melanomas from albino fishes, it was demonstrated that one of the main melanoma-associated gangliosides, GD3, was exposed predominantly in the malignant tumor. Thus, the chemical nature and even the immunohistochemical localization of the gangliosides in fish melanomas proved to be very similar to those of the known gangliosides in the phylogenetically distant human melanomas.


Asunto(s)
Enfermedades de los Peces/metabolismo , Gangliósidos/análisis , Melanoma/veterinaria , Animales , Antígenos de Neoplasias/análisis , Cromatografía en Capa Delgada , Ciprinodontiformes , Gangliósidos/inmunología , Inmunohistoquímica , Melanoma/análisis , Piel/análisis , Sulfoglicoesfingolípidos/análisis
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