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1.
Cancer Radiother ; 18(7): 709-12, 2014 Nov.
Artículo en Francés | MEDLINE | ID: mdl-25267323

RESUMEN

In August 1883, a Chair of physics was created in Nantes with Dr. Leduc (1853-1939) as the first teacher. Physician and biophysicist, he was a pioneer and visionary in many areas, including the "synthetic biology". Dr. Leduc immediately understood the importance of the discovery of the X-ray by Röntgen in 1896 for medicine. As early as in 1905, he successfully treated cancers with irradiation. In 1935, he was awarded a gold key by the American Congress of Physical Therapy for his accomplishments. The teachings of Dr Leduc largely influenced his student and successor, Dr René Gauducheau's (1881-1968) orientation towards physical and radiological sciences. This latter introduced radium therapy, and began his endeavor for the creation of a cancer center which opened its doors in 1924, recently becoming the Institut de Cancérologie de l'Ouest in 2011.


Asunto(s)
Neoplasias/historia , Oncología por Radiación/historia , Francia , Historia del Siglo XIX , Historia del Siglo XX , Neoplasias/radioterapia
2.
Oncogene ; 32(11): 1396-407, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-22580609

RESUMEN

Lethal giant larvae proteins have key roles in regulating polarity in a variety of cell types and function as tumour suppressors. A transcriptional programme initiated by aberrant Snail expression transforms epithelial cells to potentially aggressive cancer cells. Although progress in defining the molecular determinants of this programme has been made, we have little knowledge as to how the Snail-induced phenotype can be suppressed. In our studies we identified the human lethal giant larvae homologue 2, Hugl-2, (Llgl2/Lgl2) polarity gene as downregulated by Snail. Snail binds E-boxes in the Hugl-2 promoter and represses Hugl-2 expression, whereas removal of the E-boxes releases Hugl-2 from Snail repression. We demonstrate that inducing Hugl-2 in cells with constitutive Snail expression reverses the phenotype including changes in morphology, motility, tumour growth and dissemination in vivo, and expression of epithelial markers. Hugl-2 expression reduced the nuclear localization of Snail and thus binding of Snail to its target promoters. Our results placing Hugl-2 within the Snail network as well as its ability to suppress Snail carcinogenesis identifies Hugl-2 as a target molecule driving cascades, which may have preventative and therapeutic promise to minimize cancer progression.


Asunto(s)
Polaridad Celular/genética , Transformación Celular Neoplásica/genética , Proteínas del Citoesqueleto/fisiología , Proteínas Proto-Oncogénicas c-met/genética , Factores de Transcripción/fisiología , Animales , Células COS , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Células Cultivadas , Chlorocebus aethiops , Proteínas del Citoesqueleto/metabolismo , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor/fisiología , Células HEK293 , Células Hep G2 , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/prevención & control , Unión Proteica , Proteínas Proto-Oncogénicas c-met/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación hacia Arriba/genética , Regulación hacia Arriba/fisiología , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Bioresour Technol ; 102(10): 6200-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21377355

RESUMEN

The direct liquefaction of a biomass composed of a mixture of wastes (straw, wood and grass) was studied using Nickel Raney as catalyst and tetralin as a solvent. Tetralin allows to solubilize green waste from 330°C at relatively low hydrogen pressure, and avoids the recondensation of the intermediate products. The green waste deoxygenation results mainly from a decarboxylation reaction. The addition of Raney Ni in the feed, increases the gas yield due to methane formation, without diminishing the yield in solvolysis oil. The catalyst hydrogenolyses the small molecules present in the light fraction. Moreover, it improves the quality of the oil by increasing the hydrogen transfer between the solvent and the solvolysis oil. As a consequence, the oxygen content decreases and the yield of oil soluble in hexane strongly increases. The catalyst allows to obtain straight long chain alkanes (C(13)-C(26)), which result from the hydrogenation of the extractives compounds of the green waste.


Asunto(s)
Biomasa , Reciclaje , Eliminación de Residuos , Calor , Presión
4.
Clin Exp Immunol ; 159(1): 87-92, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19912254

RESUMEN

Nucleotide-binding oligomerization domain 2/caspase recruitment domain 15 (NOD2/CARD15) polymorphisms have been identified as risk factors of both Crohn's disease and graft-versus-host disease (GVHD) following allogeneic stem cell transplantation. However, the role of these receptors of innate immunity in the pathophysiology of gastrointestinal GVHD is still poorly defined. Immunohistological features of intestinal GVHD were analysed in gastrointestinal biopsies from 58 patients obtained at the time of first onset of intestinal symptoms. The observed changes were correlated with concomitant risk factors and the presence of polymorphisms within the pathogen recognition receptor gene NOD2/CARD15. Intestinal GVHD was associated with a stage-dependent decrease in CD4 T cell infiltrates and an increase in CD8 T cells in the lamina propria; CD8 infiltrates correlated with extent of apoptosis and consecutive epithelial proliferation. The presence of NOD2/CARD15 variants in the recipient was associated with a significant loss of CD4 T cells: in a semiquantitative analysis, the median CD4 score for patients with wild-type NOD2/CARD15 was 1.1 (range 3), but only 0.4 (range 2) for patients with variants (P = 0.002). This observation was independent from severity of GVHD in multivariate analyses and could not be explained by the loss of forkhead box P3(+) T cells. Our results suggest a loss of protective CD4 T cells in intestinal GVHD which is enhanced further by the presence of NOD2/CARD15 variants. Our study might help to identify more selective therapeutic strategies in the future.


Asunto(s)
Movimiento Celular/inmunología , Enfermedad Injerto contra Huésped/genética , Enfermedad Injerto contra Huésped/inmunología , Intestinos/inmunología , Proteína Adaptadora de Señalización NOD2/genética , Trasplante de Células Madre de Sangre Periférica , Polimorfismo Genético/inmunología , Corticoesteroides/farmacología , Corticoesteroides/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Recuento de Células , Movimiento Celular/efectos de los fármacos , Factores de Transcripción Forkhead/metabolismo , Enfermedad Injerto contra Huésped/patología , Humanos , Inmunosupresores/farmacología , Inmunosupresores/uso terapéutico , Mucosa Intestinal/patología , Intestinos/efectos de los fármacos , Intestinos/patología , Persona de Mediana Edad , Membrana Mucosa/patología , Neutrófilos/patología , Trasplante Homólogo/inmunología
5.
Internist (Berl) ; 50(9): 1149-51, 1153-4, 2009 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-19533073

RESUMEN

Chronic inflammatory diseases can induce further complications such as secondary amyloidosis. Being a rare but serious complication it affects typically the kidneys resulting in a nephrotic syndrome. Further sites of AA amyloid deposition are liver, heart and the autonomic nervous system. We report about a patient with congenital neutropenia, AA amyloidosis and chronic intestinal bowel inflammation due to amyloid deposition in the bowel.


Asunto(s)
Amiloidosis Familiar/complicaciones , Amiloidosis Familiar/diagnóstico , Diarrea/etiología , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/diagnóstico , Neutropenia/congénito , Neutropenia/diagnóstico , Adulto , Diarrea/diagnóstico , Humanos , Masculino , Síndrome
6.
Br J Cancer ; 98(12): 1993-8, 2008 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-18542065

RESUMEN

Carcinoma cells lack syndecan-1 expression when they are transiting from an epithelial to a less-differentiated mesenchymal phenotype (epithelial-mesenchymal transition, EMT). Furthermore, a shift of syndecan-1 expression from malignant epithelial cells to reactive stromal cells has also been observed during progression of many carcinomas. Finally, epithelial and/or stromal syndecan-1 expression is of prognostic value in many carcinomas. Because recent results are contradictory in breast carcinomas, we have re-evaluated the prognostic significance of syndecan-1 expression in a cohort of 80 patients with invasive ductal breast carcinomas. The tumours from 80 patients diagnosed with invasive ductal breast carcinomas were used to construct a tissue microarray, which was stained with syndecan-1 by immunohistochemistry. We correlated syndecan-1 expression with clinicopathologic parameters and relapse-free survival (RFS). Exclusive epithelial expression of syndecan-1 is observed in 61.25% of the patients, whereas exclusive stromal expression is observed in 30% of the patients. Only 8.75% of the patients had both stromal and epithelial expressions of syndecan-1. A significant correlation was found between the loss of syndecan-1 epithelial expression and the syndecan-1 stromal expression with high grade of malignancy (P=0.011). The loss of syndecan-1 epithelial expression is correlated with RFS (P=0.001). Using multivariate Cox analysis, loss of epithelial syndecan-1 expression was the only prognostic indicator (P<0.001). We concluded that the loss of syndecan-1 epithelial expression was of strong prognostic value in breast carcinomas.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Sindecano-1/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Análisis Multivariante , Pronóstico
7.
Gut ; 57(7): 911-21, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18308830

RESUMEN

BACKGROUND: Substance P (SP) is a pro-inflammatory neuropeptide in colitis, whereas sympathetic neurotransmitters are anti-inflammatory at high concentrations. AIM AND METHODS: In all layers of the colon, nerve fibre densities of SP(+) and sympathetic nerve fibres were investigated (22 Crohn's disease, six diverticulitis, and 22 controls). In addition, the nerve fibre repellent factor semaphorin 3C (SEMA3C) was studied. The functional role of the sympathetic nervous system was tested in dextran sodium sulfate (DSS) and Il10(-/-) colitis. RESULTS: In all layers, Crohn's disease patients demonstrated a loss of sympathetic nerve fibres. Sprouting of SP(+) nerve fibres was particularly observed in the mucosa and muscular layer in Crohn's disease. SEMA3C was detected in epithelial cells, and there was a marked increase of SEMA3C-positive crypts in the mucosa of Crohn's disease patients compared to controls. In Crohn's disease, the number of SEMA3C-positive crypts was negatively related to the density of mucosal sympathetic nerve fibres. Sympathectomy reduced acute DSS colitis but increased chronic DSS colitis. Sympathectomy also increased chronic colitis in Il10(-/-) mice. CONCLUSIONS: This study demonstrated a loss of sympathetic and an increase of SP(+) nerve fibres in Crohn's disease. SEMA3C, a sympathetic nerve repellent factor, is highly expressed in the epithelium of Crohn's disease patients. In chronic experimental colitis, the sympathetic nervous system confers an anti-inflammatory influence. Thus, the loss of sympathetic nerve fibres in the chronic phase of the disease is most probably a pro-inflammatory signal, which might be related to repulsion of these fibres by SEMA3C and other repellents.


Asunto(s)
Colon/inervación , Enfermedad de Crohn/patología , Sistema Nervioso Simpático/patología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colitis/fisiopatología , Colon/metabolismo , Colon/patología , Enfermedad de Crohn/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Diverticulitis del Colon/metabolismo , Diverticulitis del Colon/patología , Femenino , Humanos , Interferón gamma/biosíntesis , Interleucina-10/deficiencia , Ganglios Linfáticos/patología , Masculino , Mesenterio , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Persona de Mediana Edad , Fibras Nerviosas/patología , Sustancia P/metabolismo , Sistema Nervioso Simpático/fisiopatología , Factor de Necrosis Tumoral alfa/biosíntesis
8.
Clin Exp Immunol ; 152(2): 285-97, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18336593

RESUMEN

Recently we identified galectin-3 (gal-3), which is secreted by colonic epithelial cells (CEC), to be a strong activator of colonic lamina propria fibroblasts (CLPF). Modulation of CLPF function may play a role during stricture and fistula formation in inflammatory bowel disease (IBD). Therefore, we investigated further the expression of gal-3 and effects on CLPF. The aim of this study is to perform a direct comparison of gal-3 between tissue from healthy controls and from patients with either Crohn's disease (CD) or ulcerative colitis (UC). CEC, CLPF and intestinal macrophages (IMAC) were isolated from control and IBD colonic tissue. Interleukin-8 secretion as a readout of CLPF activation was quantified by enzyme-linked immunosorbent assay. Gal-3 in cell cultures and tissue samples was evaluated by Western blot, immunofluorescence and immunohistochemistry. CLPF-migration was assayed in the 48-well modified Boyden chamber. Gal-3 expression was found in all segments of the colon. In the terminal ileum, less gal-3 was found compared with the colon. Immunohistochemistry and immunofluorescence revealed a homogenous distribution of gal-3 in CEC and IMAC of control mucosa and UC. However, significantly less gal-3 was found in IMAC from CD patients. In CD fistulae and stenoses, gal-3 expression was reduced significantly and barely detectable. In co-incubation studies lactose reduced significantly the CLPF-stimulatory potential of gal-3, indicating that the C-terminal domain of gal-3 is responsible for CLPF activation. Gal-3 stimulated CLPF migration in CLPF derived from fistulae. In conclusion, gal-3 expression is down-regulated in CD-fistulae and stenoses as well as in IMAC in CD patients. Gal-3 induces migration of CLPF derived from fistulae. Its role for stricture and fistula formation warrants further investigation.


Asunto(s)
Colitis Ulcerosa/inmunología , Enfermedad de Crohn/inmunología , Fibroblastos/inmunología , Galectina 3/inmunología , Adolescente , Adulto , Anciano , Células Cultivadas , Femenino , Fibroblastos/efectos de los fármacos , Galectina 3/antagonistas & inhibidores , Galectina 3/biosíntesis , Galectina 3/genética , Expresión Génica , Humanos , Íleon/inmunología , Fístula Intestinal/inmunología , Mucosa Intestinal/inmunología , Obstrucción Intestinal/inmunología , Intestino Grueso/inmunología , Lactosa/farmacología , Macrófagos/inmunología , Masculino , Persona de Mediana Edad , ARN Mensajero/genética
9.
Gut ; 57(2): 243-51, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17881540

RESUMEN

BACKGROUND: Melanoma inhibitory activity 2 (MIA2) is a novel gene of the MIA gene family. The selective expression of MIA2 in hepatocytes is controlled by hepatocyte nuclear factor (HNF) 1 binding sites in the MIA2 promotor. In contrast, in most hepatocellular carcinomas (HCC) MIA2 expression is down-regulated or lost. AIM: In this study we examined the regulation and functional role of MIA2 in hepatocancerogenesis. METHODS AND RESULTS: In HCC cell lines and tissues HNF-1 expression was lower than in primary human hepatocytes (PHH) and corresponding non-tumorous tissue, respectively, and correlated significantly with the down-regulation of MIA2 expression. Re-expression of HNF-1 in HCC cells reinduced MIA2 in HCC cells to similar levels as found in PHH. Further, MIA2 was re-expressed in HCC cell lines by stable transfection, and the generated cell clones revealed a strongly reduced invasive potential and proliferation rate in vitro. In line with these findings treatment of HCC cells with recombinant MIA2 inhibited proliferation and invasion. In nude mice MIA2 re-expressing HCC cells grew significantly slower and revealed a less invasive growth pattern. Immunohistochemical analysis of a tissue microarray containing HCC and corresponding non-cancerous liver tissue of 85 patients confirmed reduced MIA2 expression in HCC. Furthermore, MIA2 negative HCC tissue showed a significantly higher Ki67 labelling index and loss of MIA2 expression correlated significantly with more advanced tumour stages. CONCLUSION: This study presents MIA2 as an inhibitor of HCC growth and invasion both in vitro and in vivo, and consequently, as a tumour suppressor of HCC. Further, our findings indicate a novel mechanism, how loss of HNF-1 expression in HCC affects tumorigenicity via down-regulation of MIA2.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de la Matriz Extracelular/genética , Genes Supresores de Tumor , Neoplasias Hepáticas/genética , Proteínas de Neoplasias/genética , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias , Ciclo Celular , Proliferación Celular , Células Cultivadas , Regulación hacia Abajo , Proteínas de la Matriz Extracelular/antagonistas & inhibidores , Femenino , Factor Nuclear 1 del Hepatocito/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/antagonistas & inhibidores
10.
Gut ; 56(1): 43-51, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16709662

RESUMEN

BACKGROUND: Colonic lamina propria fibroblasts (CLPFs) play an important role in the pathogenesis of fibrosis and strictures in Crohn's disease. AIM: To identify colonic epithelial cell (CEC)-derived factors that activate CLPFs. METHODS: Primary human CECs and CLPFs were isolated from control mucosa and interleukin 8 (IL8) of CLPF cultures was quantified by ELISA. Activation of nuclear factor kappaB (NF-kappaB) was shown, and translocation of NF-kappaB was inhibited by a dominant-negative IkappaB-expressing adenovirus. The major CLPF-activating and IL8 inducing protein was purified using fast-performance liquid chromatography (HiPrep 16/60 Sephacryl S-200 High Resolution Column) and sodium dodecyl sulphate gel electrophoresis. RESULTS: A considerable increase in IL8 secretion by CLPFs cultured in CEC-conditioned media compared with that in unconditioned media (155.00 (10.00) pg/microg v 1.434 (0.695) pg/microg) was found. The effect of CEC-conditioned media on CLPF IL8 secretion was NF-kappaB dependent. A protein or DNA array confirmed the involvement of NF-kappaB and activator protein-1. Purification of a candidate band isolated with the use of sodium dodecyl sulphate-polyacrylamide gel electrophoresis and subsequent sequencing showed soluble galectin-3 to be a strong CLPF-activating factor. Depletion of galectin-3 from conditioned media by immunoprecipitation abolished the CLPF stimulatory effect. CONCLUSIONS: Using a classical biochemical approach, soluble galectin-3 was identified as a strong activator of CLPFs produced by CEC. Galectin-3 induced NF-kappaB activation and IL8 secretion in these cells and may be a target for future therapeutic approaches to reduce or avoid stricture formation.


Asunto(s)
Colon/química , Fibroblastos/efectos de los fármacos , Galectina 3/análisis , Membrana Mucosa/química , Adulto , Anciano , Anciano de 80 o más Años , Células CACO-2 , Línea Celular , Células Cultivadas , Neoplasias Colorrectales/patología , Medios de Cultivo Condicionados , Diverticulitis/patología , Células Epiteliales/química , Femenino , Células HT29 , Humanos , Interleucina-8/análisis , Enfermedades Intestinales/patología , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , Factor de Transcripción AP-1/metabolismo
11.
Oncogene ; 26(28): 4158-70, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17173062

RESUMEN

Analyses of malignant melanomas revealed a strong expression of bone morphogenic proteins (BMPs) and their autocrine effect in promoting cell invasion and migration. Here, we report a paracrine effect of BMPs on the vascular network. Both BMP2 and BMP4 induced tube formation as well as the migratory efficiency of microvascular endothelial cells. Melanoma cells with reduced BMP activity attracted less endothelial cells in invasion assays than control cells. Furthermore, reduction of BMPs in melanoma cells had a strong effect on vasculogenic mimicry. Tube formation on matrigel was analysed for melanoma cells as well as in co-cultures of endothelial and melanoma cells. Melanoma cells with reduced BMP activity were not capable of forming cord-like structures by themselves and additionally inhibited tube formation of the endothelial cells. Genes involved in angiogenesis turned out to be strongly downregulated in these cell clones. Tumors derived from cells with impaired BMP activity showed reduced tumor growth or large necrotic areas owing to lack of angiogenesis in in vivo analyses.


Asunto(s)
Proteínas Morfogenéticas Óseas/fisiología , Melanoma/irrigación sanguínea , Neovascularización Patológica , Animales , Secuencia de Bases , Proteína Morfogenética Ósea 4 , Proteínas Morfogenéticas Óseas/metabolismo , Línea Celular Tumoral , Células Cultivadas , Cartilla de ADN , Humanos , Inmunohistoquímica , Melanoma/metabolismo , Melanoma/patología , Ratones , Ratones Desnudos
12.
Clin Exp Immunol ; 146(1): 169-80, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16968411

RESUMEN

The cathepsins D (CTSD), B (CTSB) and L (CTSL) are important for the intracellular degradation of proteins. Increased cathepsin expression is associated with inflammatory diseases. We have shown previously an induction of CTSD expression in intestinal macrophages (IMAC) in inflamed mucosa of patients with inflammatory bowel disease (IBD). Here we investigated the regulation of CTSB and CTSL in IMAC during IBD and effects of CTSD and CTSB/CTSL inhibition in vivo. Human IMAC were isolated from normal and inflamed mucosa. Reverse transcription-polymerase chain reaction (RT-PCR) was performed for CTSB and CTSL mRNA. Immunostaining was used to confirm PCR results. Cathepsin inhibition was investigated in the dextran-sulphate-sodium (DSS) colitis model in mice with application of pepstatin A (CTSD inhibitor), CA-074 (CTSB inhibitor) and Z-Phe-Tyr-aldehyde (CTSL inhibitor). CTSL mRNA was significantly up-regulated in IMAC isolated from IBD mucosa. Up-regulated protein expression was found mainly in areas of mucosal damage by immunostaining. Inhibition of CTSD in mouse DSS colitis was followed by an amelioration of the disease. Inhibitor-treated mice showed a significant lower histological score (HS) and less colon reduction in comparison to controls. Similarly, simultaneous inhibition of CTSB/CTSL was followed by a significant amelioration of colitis. Expression of tissue-degrading cathepsins is increased in IMAC in IBD. Inhibition of CTSD as well as CTSB/CTSL is followed by an amelioration of experimental colitis. The prevention of mucosal damage by cathepsin inhibition could represent a new approach for the therapy of IBD.


Asunto(s)
Catepsinas/biosíntesis , Enfermedades Inflamatorias del Intestino/enzimología , Macrófagos/enzimología , Animales , Catepsina B/antagonistas & inhibidores , Catepsina B/biosíntesis , Catepsina B/genética , Catepsina D/antagonistas & inhibidores , Catepsina D/biosíntesis , Catepsina D/genética , Catepsina L , Catepsinas/antagonistas & inhibidores , Catepsinas/genética , Colitis/tratamiento farmacológico , Colitis/patología , Cisteína Endopeptidasas/biosíntesis , Cisteína Endopeptidasas/genética , Inhibidores de Cisteína Proteinasa/uso terapéutico , Dipéptidos/uso terapéutico , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Humanos , Mucosa Intestinal/enzimología , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
13.
Oncogene ; 25(36): 5027-36, 2006 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-16568085

RESUMEN

The Dickkopf (DKK) genes were originally identified as factors inducing head formation in Xenopus. The genes code for inhibitors that are involved in Wnt signaling. We speculate that loss of DKK expression plays a role in development or progression of malignant melanoma. Thus, we evaluated melanoma cell lines and tissue samples of malignant melanoma for loss of DKK, especially DKK-3 transcription. We found that DKK-1, -2 and -3 were downregulated or lost in all cell lines and in most of the tumor samples analysed. Reduced DKK-3 expression occurred as early as in primary tumors detected by both immunohistochemical and reverse transcription-polymerase chain reaction RT-PCR analysis. Functional assays with stable DKK-3 transfected cell lines revealed that DKK-3 expression increased cell-cell adhesion and decreased cell migration. Further, downregulation of fibronectin, snail-1 and re-expression of E-cadherin was found in the DKK-3 expressing cell clones supporting a role of DKK-3 in tumor progression. Our studies thus indicate that loss of DKK-3 expression may contribute to melanoma progression.


Asunto(s)
Expresión Génica , Péptidos y Proteínas de Señalización Intercelular/genética , Melanoma/genética , Proteínas Adaptadoras Transductoras de Señales , Adhesión Celular , Línea Celular Tumoral , Quimiocinas , Genes Supresores de Tumor , Humanos , Inmunohistoquímica , Melanoma/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
J Clin Pathol ; 59(7): 699-705, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16565225

RESUMEN

AIM: To investigate whether protein expression or cellular localisation of P-cadherin is associated with clinicopathological characteristics in benign and malignant melanocytic skin tumours. EXPERIMENTAL DESIGN: P-cadherin expression and the Ki-67 labelling index were analysed immunohistochemically by using tissue microarrays (TMAs). Membranous and cytoplasmic expression was scored semiquantitatively (0 to 2+). RESULTS: P-cadherin protein expression of any intensity (1+ to 2+) was detected in the membrane in 41.5% (132/318) and in the cytoplasm in 64.2% (204/318) of patients. In general, P-cadherin expression was significantly reduced in malignant melanomas (p<0.001) and melanoma metastases (p<0.001), compared with benign nevi. Additionally, loss of membranous P-cadherin was associated with Clark level (p = 0.011) and tumour thickness (p<0.001). Interestingly, a significantly lower P-cadherin expression was shown by dermal nevi than by compound and junctional nevi (p = 0.005; p = 0.025). In primary melanomas, a Ki-67 labelling index <5% was not associated with P-cadherin protein expression, suggesting that loss of P-cadherin expression was not associated with proliferation. None of the other clinical and histological factors analysed was significantly related to P-cadherin expression. Low cytoplasmic P-cadherin expression was associated with tumour recurrence (p = 0.03) in all the patients who were analysed. After testing various multivariate Cox regression models, loss of cytoplasmic P-cadherin expression remained a highly significant adverse risk factor for tumour recurrence in patients with tumours <2 mm. CONCLUSIONS: Loss of cytoplasmic P-cadherin expression is common in advanced melanomas and can be a prognostic marker of progression in patients with melanoma, most useful in patients with primary tumours <2 mm in thickness.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Melanoma/metabolismo , Nevo Pigmentado/metabolismo , Neoplasias Cutáneas/metabolismo , Anciano , Membrana Celular/metabolismo , Citoplasma/metabolismo , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Melanoma/patología , Melanoma/secundario , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Estadificación de Neoplasias , Nevo Pigmentado/patología , Pronóstico , Análisis por Matrices de Proteínas/métodos , Recurrencia , Neoplasias Cutáneas/patología
15.
Oncogene ; 25(1): 103-10, 2006 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-16170365

RESUMEN

The human gene Hugl-1 (Llgl/Lgl1) has significant homology to the Drosophila tumor suppressor gene lethal(2)giant larvae (lgl). The lgl gene codes for a cortical cytoskeleton protein, Lgl, that is involved in maintaining cell polarity and epithelial integrity. We speculate that Hugl-1 might play a role in epithelial-mesenchymal transition (EMT) and that loss of Hugl-1 expression plays a role in the development or progression of malignant melanoma. Thus, we evaluated melanoma cell lines and tissue samples of malignant melanoma for loss of Hugl-1 transcription. We found that Hugl-1 was downregulated or lost in all cell lines and in most of the tumor samples analysed, and that these losses were associated with advanced stage of the disease. Reduced Hugl-1 expression occurred as early as in primary tumors detected by both immunohistochemical and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Functional assays with stable Hugl-1-transfected cell lines revealed that Hugl-1 expression increased cell adhesion and decreased cell migration. Further, downregulation of MMP2 and MMP14 (MT1-MMP) and re-expression of E-cadherin was found in the Hugl-1-expressing cell clones supporting a role of Hugl-1 in EMT. Our studies thus indicate that loss of Hugl-1 expression contributes to melanoma progression.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Melanoma/metabolismo , Proteínas/metabolismo , Western Blotting , Cadherinas/biosíntesis , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Proteínas del Citoesqueleto , Progresión de la Enfermedad , Regulación hacia Abajo , Epitelio/patología , Humanos , Inmunohistoquímica , Metaloproteinasa 14 de la Matriz , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasas de la Matriz/biosíntesis , Metaloproteinasas de la Matriz Asociadas a la Membrana , Melanoma/genética , Microscopía Fluorescente , Invasividad Neoplásica , Proteínas/genética , ARN/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Distribución Tisular , Transcripción Genética , Transfección
16.
Gut ; 54(7): 935-43, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15951537

RESUMEN

BACKGROUND: The glycoprotein (gp) 96 links the adaptive with the innate immune system. It is a chaperone with a binding domain for peptides generated by proteasomal degradation. During cellular stress, peptide loaded gp96 can be released and presented to T cells by antigen presenting cells (APCs). METHODS: mRNAs from in vitro differentiated macrophages (iv mac) and normal intestinal macrophages (IMACs) were compared by subtractive hybridisation and Affymetrix GeneChip analysis. Differentiation induced expression of gp96 was investigated in the multicellular spheroid (MCS) model. In vivo gp96 protein expression was detected by double labelling immunohistochemistry of human colon and in the CD4+ CD62L+ T cell transfer mouse model. RESULTS: Five of 76 clones obtained by subtractive hybridisation revealed >99% sequence homology to gp96. Affymetrix GeneChip analysis confirmed induction of gp96 in IMACs. Gp96 mRNA was detected in IMACs from normal and intestinal bowel disease mucosa. Induction of gp96 protein was observed after seven days in the MCS model of IMAC differentiation. Immunohistochemistry confirmed the presence of gp96 protein in IMACs in normal mucosa as well as in mucosa from patients with ulcerative colitis and diverticulitis. In mucosa from Crohn's disease (CD) patients, gp96 protein was not detectable. In the CD4+ CD62L+ T cell transfer mouse model, gp96 was verifiable in non-activated IMACs. CONCLUSION: Gp96 is induced during differentiation of normal IMACs but is not detected in IMACs in CD mucosa. As gp96 has been described as having a role in tolerance induction, this may be relevant for loss of tolerance against luminal bacteria found in CD patients.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Enfermedad de Crohn/metabolismo , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/fisiología , Diferenciación Celular/fisiología , Células Cultivadas , Colitis/metabolismo , Modelos Animales de Enfermedad , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Esferoides Celulares
17.
Clin Exp Immunol ; 140(3): 547-55, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15932518

RESUMEN

Haem-oxygenase-1 (HO-1) has been shown to exert anti-inflammatory, anti-apoptotic and anti-proliferative effects. We investigated HO-1 expression in patients with inflammatory bowel disease (IBD) and could demonstrate a scattered expression of HO-1 in the intestinal epithelium of severely inflamed colonic mucosa of patients with IBD compared to control specimens such as diverticulitis, suggesting dysregulated expression in IBD. To further analyse potential mechanisms of HO-1 induction in the intestine we employed an in vitro epithelial cell apoptosis model and an experimental colitis model. In vitro induction of HO-1 by the HO-1 inducer cobalt protoporphyrin (CoPP) resulted in a dose-dependent down-regulation of caspase-3 activation in HT-29 cells, indicating an anti-apoptotic function of HO-1 in the intestine. In vivo, preventive HO-1 induction by CoPP in acute dextran sodium sulphate (DSS)-induced colitis led to a significant down-regulation of colonic inflammation (P < 0.01) with a concomitant reduction in interferon (IFN)-gamma - but unaffected interleukin (IL)-10-secretion by isolated mesenteric lymph nodes (P < 0.01). Additionally, TUNEL staining of colonic sections demonstrated fewer apoptotic epithelial cells in the colon of CoPP treated animals. No beneficial effects were observed if HO-1 was induced by CoPP after the onset of acute colitis or in chronic DSS-induced colitis. In conclusion, the data suggest a protective role of HO-1 if it is induced before the onset of inflammation. However, as shown by the lack of effects in established acute or in chronic colitis, the induction of HO-1 may not be a promising approach for the treatment of IBD.


Asunto(s)
Hemo Oxigenasa (Desciclizante)/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedad Aguda , Animales , Apoptosis/inmunología , Caspasa 3 , Caspasas/inmunología , Línea Celular Tumoral , Enfermedad Crónica , Colitis Ulcerosa/inmunología , Colon/inmunología , Enfermedad de Crohn/inmunología , Regulación hacia Abajo/inmunología , Femenino , Hemo Oxigenasa (Desciclizante)/análisis , Hemo-Oxigenasa 1 , Humanos , Inmunohistoquímica/métodos , Etiquetado Corte-Fin in Situ/métodos , Mucosa Intestinal/inmunología , Proteínas de la Membrana , Ratones , Ratones Endogámicos BALB C , Protoporfirinas/inmunología , Regulación hacia Arriba/inmunología
18.
Histopathology ; 47(1): 57-66, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15982324

RESUMEN

AIMS: To determine the expression of a protein termed augmenter of liver regeneration (ALR), recently found to have a specific and beneficial effect on the process of liver regeneration in normal and diseased human liver. METHODS AND RESULTS: ALR expression in normal and cirrhotic human livers with various underlying diseases as well as in tissue samples of hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) was analysed by immunohistochemistry and quantitative reverse transciptase-polymerase chain reaction (RT-PCR). Expression analysis of ALR in total liver protein extracts by Western blotting showed mainly dimeric ALR protein. Immunohistochemically, cytosolic and perinuclear immunosignals were found in hepatocytes and cholangiocytes in normal, cirrhotic or cancerous liver tissue and only weak signals in some endothelial cells in normal livers. Quantitative mRNA analysis revealed significantly increased ALR expression in cirrhosis compared with normal liver tissue. In HCC and CCC ALR mRNA expression was also significantly enhanced compared with normal liver tissue, but expression levels did not differ from the matching non-neoplastic tissue in the same patient. CONCLUSIONS: The findings suggest an important role for ALR in hepatocellular regeneration in liver cirrhosis as well as in hepatocarcinogenesis and therefore its potential value in the clinical diagnosis of hepatic cirrhosis and cancer.


Asunto(s)
Carcinoma Hepatocelular/patología , Reductasas del Citocromo/genética , Factor de Crecimiento de Hepatocito/genética , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Anciano , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/metabolismo , Conductos Biliares Intrahepáticos/patología , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Reductasas del Citocromo/metabolismo , Femenino , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Inmunohistoquímica , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Gut ; 53(9): 1314-21, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15306592

RESUMEN

BACKGROUND: Fistulae are a common complication in up to 35% of all patients with Crohn's disease. Their therapy is difficult and frequently unsatisfactory. To date, no histological comparison of Crohn's disease fistulae with non-inflammatory bowel disease fistulae has been performed. In addition, Crohn's disease fistulae have not been well characterised morphologically. METHODS: Eighty four fistulae from Crohn's disease patients were compared with 13 fistulae from controls. Haematoxylin-eosin staining, electron microscopy, and immunohistochemistry for panCytokeratin (epithelial cells), CD20 (B cells), CD45R0 (T cells), and CD68 (macrophages) were performed according to standard techniques. In addition, histopathological findings were compared with clinical and laboratory data. RESULTS: In 31.0% of controls and 27.4% of Crohn's disease specimens, fistulae had a lining of flattened intestinal epithelium without goblet cells or, in the case of cutaneous/perianal disease, narrow squamous epithelium. Non-epithelialised fistulae were covered by a thin layer of (myo)fibroblasts, focally forming a new basement membrane, as demonstrated by electron microscopy. All fistulae were surrounded by granulation tissue. Crohn's disease fistulae presented with central infiltration by CD45R0+ T cells, followed by a small band of CD68+ macrophages and dense accumulation of CD20+ B cells. In contrast, in controls, there was dense infiltration by CD68+ macrophages with only few CD20+ B cells and CD45R0+ T lymphocytes. CONCLUSIONS: Fistulae in Crohn's disease differ markedly from non-Crohn's disease fistulae with regard to their cellular composition. The presence of an epithelial lining in a subgroup of fistulae may be important for the therapeutic approach and healing process.


Asunto(s)
Enfermedad de Crohn/complicaciones , Fístula Intestinal/etiología , Fístula Intestinal/patología , Adolescente , Adulto , Anciano , Subgrupos de Linfocitos B/patología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/patología , Femenino , Humanos , Técnicas para Inmunoenzimas , Fístula Intestinal/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/ultraestructura , Macrófagos/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Subgrupos de Linfocitos T/patología
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