Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Cancer Metastasis Rev ; 31(1-2): 269-76, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22438090

RESUMEN

Cancer metastasis results from positive and negative cellular events such as constitutive activation of oncogenes (cOA) or genetic losses (GL) being modulated by downstream signals of epithelial-mesenchymal or mesenchymal-epithelial transition, thus constituting master programs of metastatic phenotype and site specificity. To address the complex nature of these programs, we introduced clinical and phenotypic markers like tumor size, grade, cellular shape, or expression of E-cadherin in 27 colon cancer (CC) patients (cOA and GL), and 41 patients with gastrointestinal stromal tumors (GIST, cOA) to produce scores of cOA and GL. Scores of cOA were highest in case of hepatic and lower in case of an isolated peritoneal spread (GIST), or (CC) of both, cOA and GL, highest in case of a combined hepatic and peritoneal spread and lower in case of an isolated peritoneal spread; but in case of an isolated hepatic spread, scores of cOA were high and low of GL. This indicates a differential contribution of cellular dissociation and recognition in site-specific metastasis, of cOA predominantly in production of hepatic and in the case of GL of serosal spread.


Asunto(s)
Metástasis de la Neoplasia , Neoplasias/metabolismo , Neoplasias/patología , Cadherinas/genética , Cadherinas/metabolismo , Diferenciación Celular/genética , Transición Epitelial-Mesenquimal/genética , Humanos , Metástasis de la Neoplasia/genética , Neoplasias/genética , Oncogenes , Fenotipo , Transducción de Señal
2.
Phlebology ; 26(4): 135-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20881312

RESUMEN

BACKGROUND: The purpose of this study was to compare the genetic background of superficial (SVT) and deep vein thrombosis (DVT). METHODS: Factor V (FV)-Leiden (G16891A)-, factor II(G20210A)-mutations, protein C- and S, as well as methylenetetrahydrofolate reductase (MTHFR) polymorphisms at C677T and A1298C, and serum homocysteine levels (hcy) were determined in 29 patients with SVT and 26 with DVT. Findings FV- and -II-mutations were less frequent in patients with SVT (2/3) compared with DVT (9/5), respectively (P < 0.002 in case of FV). However, the frequency of the MTHFR C677T polymorphism was significantly higher in patients with SVT compared with DVT (CT 12 versus 10, and TT 7 versus 1, respectively, P << 0.001). The distribution of the MTHFR A1298C genotype and serum hcy levels was similar in both patient groups. Protein S-deficiency was recorded once (SVT). Interpretation These results suggest that the MTHFR C677T-mutant genetically predisposes its carriers to SVT which may contribute to hypercoagulation in pre-existing varicose vein disease.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Mutación Missense , Tromboflebitis/genética , Várices/genética , Adulto , Anciano , Anciano de 80 o más Años , Sustitución de Aminoácidos , Factor V/genética , Factor V/metabolismo , Femenino , Homocisteína/sangre , Homocisteína/genética , Humanos , Masculino , Metilenotetrahidrofolato Deshidrogenasa (NADP)/sangre , Persona de Mediana Edad , Protrombina/genética , Protrombina/metabolismo , Tromboflebitis/sangre , Tromboflebitis/complicaciones , Várices/sangre , Várices/etiología , Trombosis de la Vena/sangre , Trombosis de la Vena/etiología , Trombosis de la Vena/genética
3.
Zentralbl Chir ; 132(6): 509-14, 2007 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-18098078

RESUMEN

The purpose was to generate a score targeted at the metastatic risk potentially reflecting oncogenic activation in Gastrointestinal Stromal Tumours (GIST). In 41 patients size and location of the primary, mitotic index, initial symptoms, and histological appearance were rated with 0 to 1 or 2 points. The course of the disease was recorded as incidental, symptomatic, locally recurrent, with peritoneal dissemination, or with hepatic spread. The parameters tumour size (p < 0.001), mitotic index (p < 0.001), localisation of the primary (p < 0.001) and symptoms (p < 0.05) correlated with the course of the disease. This correlation was highly significant (p << 0.0005) when the overall score was applied, the median being 0 in incidental, 3 in symptomatic, 4 in locally recurrent, 4.5 in peritoneal, and 5 points in hepatic spreading GIST. Results were compared with those of an established risk stratification. The sensitivity and specificity of a score > 4 for the occurrence of liver metastases were 100 and 73.5 % compared with 85.7 and 82.4 % for a high risk profile according to Franquemont's classification. The results indicate the ability of routinely recorded data to predict the metastatic outcome of GIST.


Asunto(s)
Tumores del Estroma Gastrointestinal/patología , Neoplasias Hepáticas/secundario , Índice Mitótico , Neoplasias Peritoneales/secundario , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/mortalidad , Tumores del Estroma Gastrointestinal/cirugía , Tracto Gastrointestinal/patología , Tracto Gastrointestinal/cirugía , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Neoplasias Peritoneales/diagnóstico , Neoplasias Peritoneales/mortalidad , Neoplasias Peritoneales/patología , Pronóstico , Proyectos de Investigación , Factores de Riesgo , Tasa de Supervivencia
4.
Clin Exp Metastasis ; 21(1): 75-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15065605

RESUMEN

A pilot study was conducted to determine the concentrations of soluble serum E-cadherin in 36 patients with colorectal cancer or a high-grade dysplasia by the use of an ELISA technique. The results were compared with staging characteristics and concentrations of routine serum carcinoembryonic antigen (CEA). Sixteen patients with benign diseases and nine healthy volunteers served as internal or negative controls. Tumour specimens from seven patients were analysed by immunohistochemistry to compare concentrations of soluble serum E-cadherin with patterns of cell-bound E-cadherin or beta-catenin. Serum E-cadherin concentrations were increased in colorectal cancer patients (P = 0.009), but also in benign disease controls (P = 0.005), correlating with the T- (P < 0.05), but not N- or M-stage, and with serum CEA (P = 0.002) in case of existing liver metastases. Compared with other staining patterns, concentrations of soluble serum E-cadherin were higher in case of an exclusive membrane-bound localization of cellular beta-catenin (P = 0.071). The results suggest marker characteristics of soluble serum E-cadherin in colorectal cancer patients, but lacking specificity argues against a routine clinical use.


Asunto(s)
Biomarcadores de Tumor/sangre , Cadherinas/sangre , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/sangre , Progresión de la Enfermedad , Humanos , Inmunohistoquímica
5.
Zentralbl Chir ; 120(12): 981-3, 1995.
Artículo en Alemán | MEDLINE | ID: mdl-8585351

RESUMEN

We report a case of severe hyperphosphatemia following repeated use of phosphate-containing enemas in a patient with small and large bowel ileus, who died from acute renal and cardiovascular failure. Refractory hypocalcemia presumably resulted from precipitation of calcium-phosphate. Hypocalcemia may induce alterations which seriously compromise the clinical course.


Asunto(s)
Colostomía , Obstrucción Intestinal/complicaciones , Intestino Grueso/cirugía , Intestino Delgado/cirugía , Fosfatos/sangre , Complicaciones Posoperatorias/cirugía , Neoplasias del Recto/cirugía , Anciano , Enema , Humanos , Obstrucción Intestinal/cirugía , Masculino , Fosfatos/administración & dosificación , Complicaciones Posoperatorias/inducido químicamente , Reoperación
6.
J Natl Cancer Inst ; 86(12): 913-20, 1994 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-7910854

RESUMEN

BACKGROUND: The major cause of death from cancer is metastases that are resistant to conventional therapies. The resistance of metastatic tumor cells to chemotherapy can be caused by their intrinsic properties, such as increased expression of the mdr genes. PURPOSE: The purpose of our present study was to determine some of the mechanisms by which the organ microenvironment influences the response of tumor cells to chemotherapy. METHODS: Murine CT-26 colon cancer cells growing in continuous culture (parental cells) were harvested and injected subcutaneously into the lateral flank (to produce subcutaneous tumors) or the lateral tail vein (to produce experimental lung metastases) of 10 8-week-old syngeneic male BALB/c mice. Seven days after tumor-cell injection, the mice were given intravenous injections of either doxorubicin (10 mg/kg) or 0.9% NaCl (controls). This in vivo injection was repeated 7 days later. Mice with subcutaneous tumors and lung metastases were killed by cervical dislocation on day 21, and tumor samples from control mice were harvested and adapted to culture. The sensitivity of the cultured cells to doxorubicin and fluorouracil (5-FU) was determined at multiple time points. Levels of mdr-1 DNA were measured by slot-blot and Southern-blot analyses. mdr mRNA expression levels were measured by Northern-blot analysis using mdr-1- and mdr-3-specific hybridization probes, and P-glycoprotein level was determined by fluorescence-activated cell sorting using different monoclonal antibodies. RESULTS: Treatment with doxorubicin produced 80% growth inhibition of CT-26 subcutaneous tumors but had little effect on the number (and size) of experimental lung metastases. Collectively, the results suggest that the multidrug-resistant phenotype developed in CT-26 cells growing in the lung environment. Cultures established from lung metastases were initially resistant to doxorubicin (but not to 5-FU) and showed elevated expression of mdr-1 mRNA transcripts and P-glycoprotein. This resistance could be overcome by verapamil and disappeared after 21 days in culture. No mdr gene amplification was detected. The expression level of mdr-specific mRNA (predominance of mdr-1) and P-glycoprotein was directly associated with resistance to doxorubicin. CONCLUSIONS: Results of this study have demonstrated that the in vivo sensitivity of murine CT-26 colon carcinoma cells to doxorubicin depends on the organ environment. The organ environment can influence the P-glycoprotein-mediated multidrug-resistant phenotype in tumor cells, and the increased expression of P-glycoprotein is transient; once removed from the environment (lung), the cell's resistance reverts to that of the sensitive parent cells.


Asunto(s)
Carcinoma/tratamiento farmacológico , Proteínas Portadoras/genética , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Resistencia a Medicamentos , Glicoproteínas de Membrana/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Animales , Carcinoma/genética , Doxorrubicina/administración & dosificación , Expresión Génica , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Masculino , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , ARN Mensajero/genética , ARN Neoplásico/genética , Neoplasias Cutáneas/tratamiento farmacológico , Verapamilo/administración & dosificación
7.
Cancer Metastasis Rev ; 13(2): 209-22, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7923551

RESUMEN

The outcome of cancer metastasis depends on the interaction of metastatic cells with various host factors. The implantation of human cancer cells into anatomically correct (orthotopic) sites in nude mice can be used to ascertain their metastatic potential. While it is clear that vascularity and local immunity can retard or facilitate tumor growth, we have found that the organ environment also influences tumor cell functions such as production of degradative enzymes. The organ microenvironment can also influence the response of metastases to chemotherapy. It is not uncommon to observe the regression of cancer metastases in one organ and their continued growth in other sites after systemic chemotherapy. We demonstrated this effect in a series of experiments using a murine fibrosarcoma, a murine colon carcinoma, and a human colon carcinoma. The tumor cells were implanted subcutaneously or into different visceral organs. Subcutaneous tumors were sensitive to doxorubicin (DXR), whereas lung or liver metastases were not. In contrast, sensitivity to 5-FU did not differ between these sites of growth. The differences in response to DXR between s.c. tumors (sensitive) and lung or liver tumors (resistant) were not due to variations in DXR potency or DXR distribution. The expression of the multidrug resistance-associated P-glycoprotein as determined by flow cytometric analysis of tumor cells harvested from lesions in different organs correlated inversely with their sensitivity to DXR: increased P-glycoprotein was associated with overexpression of mdr1 mRNA. However, the organ-specific mechanism for upregulating mdr1 and P-glycoprotein has yet to be elucidated.


Asunto(s)
Antineoplásicos/farmacología , Metástasis de la Neoplasia/patología , Neoplasias Experimentales/patología , Animales , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Experimentales/tratamiento farmacológico , Especificidad de Órganos
8.
Int J Oncol ; 3(3): 413-22, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21573380

RESUMEN

The purpose of the study was to determine whether the organ environment can influence the response of colon cancer cells to chemotherapy. The highly metastatic human colon cancer cell line KM12L4, previously selected for production of liver metastases in nude mice, was injected into the cecal wall and into the spleen to produce liver metastases, and into the subcutis of nude mice. Doxorubicin (DOX) at 10 mg/kg or saline (control) was injected intravenously on days 7 and 16 after tumor cell injection. The in vivo response of tumors growing in the cecum, liver, and subcutaneous (s.c.) sites as well as the DOX sensitivity of cell lines established from liver and s.c. tumors were compared. Colon cancers growing s.c. were more sensitive to DOX than tumors growing in the cecal wall or liver of nude mice. The difference in response to DOX between s.c. tumors (sensitive) and liver tumors (resistant) was not due to selection of cell populations with different sensitivity to DOX, or differences in DOX distribution. PKC activity was lower in tumors of the liver and the cecum than in s.c. tumors. The expression of P-glycoprotein as determined by flow cytometric analysis of tumor cells harvested from lesions in different organs correlated inversely with their sensitivity to DOX. Increased levels of P-glycoprotein correlated with mdr-1, mdr-3 mRNA expression as determined by Northern analysis. Collectively, the data show that the organ environment influences the response of human colon carcinoma cells to DOX and recommend that animal models of this disease for experimental therapeutic studies employ orthotopic implantation of tumor cells.

9.
Int J Cancer ; 52(1): 98-104, 1992 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-1500231

RESUMEN

We determined the effects of organ environment on the response of murine CT-26 colon carcinoma cells to 2 structurally and pharmacologically distinct chemotherapeutic agents. CT-26 cells were injected i.v. (to produce lung lesions), s.c., into the cecal wall, and into the spleen (to produce spleen and liver lesions). Doxorubicin (DXR) at 10 mg/kg, 5-fluorouracil (5-FU) at 20 mg/kg, or saline (control) was injected intravenously on different schedules after tumor-cell implantation. The in vivo responses of the tumors growing in the cecum, spleen, liver, lung and subcutis were compared. Colon carcinomas growing in the subcutis were most sensitive to DXR. Tumors growing in the spleen and cecum were most sensitive to 5-FU and less so to DXR. Tumors in the liver were highly resistant to both drugs, whereas experimental lung metastases were sensitive to 5-FU but resistant to DXR. The differential responses of the tumors to the drugs were not due to drug distribution. The level of protein-kinase-C activity was elevated in the spleen, liver and cecum tumors as compared with s.c. tumors and correlated with the in vivo DXR resistance of the tumor cells. This correlation suggested that organ environment may modulate the chemosensitivity of tumor cells, at least in part, by perturbing signal transduction pathways. Collectively, the data indicate that the organ environment has profound effects on the response of tumor cells to chemotherapy. A molecular understanding of this phenomenon should facilitate the design of more effective systemic chemotherapy for cancer metastases.


Asunto(s)
Neoplasias del Colon/patología , Doxorrubicina/farmacología , Fluorouracilo/farmacología , Animales , Doxorrubicina/metabolismo , Resistencia a Medicamentos , Fluorouracilo/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Proteína Quinasa C/análisis , Células Tumorales Cultivadas
10.
J Nucl Med ; 32(2): 279-87, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1992032

RESUMEN

Tumor uptake was examined with respect to antigen expression, time-dependent biodistribution, dose of Mab injected, tumor size, and tumor site (i.e., subcutaneous versus lung or liver metastases). NR-ML-05, 96.5, and P94 showed significantly greater uptake in subcutaneous tumors than CL207 and 5.1 (p less than 0.05). NR-ML-05 had a significantly higher tumor uptake at 24 hr (11.9 +/- 0.51) than at 72 hr (4.0 +/- 0.37) or 144 hr (2.7 +/- 0.84) after injection (p less than 0.001). The other four Mabs had similar tumor distribution at all three time points. The tumor uptake of four Mabs (96.5, P94, CL207. 5.1) differed with respect to in vitro versus in vivo binding to tumor, tumor type, dose of Mab, and tumor site (subcutaneous versus metastases). In contrast, NR-ML-05 demonstrated consistent uptake in tumors independent of the above parameters. These data suggest that certain host parameters can influence in vivo tumor targeting depending on characteristics of each Mab studied.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Antígenos de Neoplasias/inmunología , Radioisótopos de Yodo , Marcaje Isotópico/métodos , Melanoma/metabolismo , Animales , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Melanoma/inmunología , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Trasplante Heterólogo
11.
Immun Infekt ; 18(2): 42-5, 1990 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-2351409

RESUMEN

In 31 children with different cytostatic treated malignancies delayed cutaneous hypersensitivity (DCH) and their relationship to different peripheral white blood-cell counts was investigated. DCH was assessed by a multi-antigen-test device, which allows the simultaneous intracutaneous application of 7 standardized recall-antigen solutions. The grade of DCH reaction was measured by a "score", which reflects the sum of the diameters of all single positive reactions. The follow-up time was 3 years for each patient. At start of therapy 17 out of 31 children had pathologically decreased score values. In 16 out of these 17 children score values increased to normal during the cytostatic treatment. Patients with score values increasing from low to normal had a significant better outcome of their disease than patients with other score courses. A good correlation was found between an increase of score values and tumor-mass reduction. No positive correlation between the score and the peripheral white blood-cell counts could be evaluated, but a significant reciprocal correlation was found between the score and the peripheral absolute lymphocyte counts. Cytostatic drugs had no influence on the score. The results suggest, that the DCH can reveal immunological alterations, which are caused by the extent of tumor burden and by specific influences on the immune system and which are almost not influenced by the administration of cytostatic drugs.


Asunto(s)
Antineoplásicos/uso terapéutico , Hipersensibilidad Tardía , Neoplasias/inmunología , Adolescente , Niño , Preescolar , Estudios de Seguimiento , Humanos , Lactante , Recuento de Leucocitos , Linfoma no Hodgkin/inmunología , Neoplasias/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología
12.
Chirurg ; 61(3): 183-6, 1990 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-2160880

RESUMEN

We report 5 cases of acute vitamin B-1 induced lactic acidosis in surgical patients receiving parenteral nutrition. In all patients treatment with vitamin B-1 induced a dramatical improvement of clinical findings. 4 patients recovered completely, 1 patient died from already developed irreversible cardiocirculatory failure. These cases underline the need for regular vitamin B-1 substitution in patients with parenteral nutrition and preoperatively in alcoholics and in patients, in whom a sufficient food intake can not be assured.


Asunto(s)
Acidosis Láctica/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Deficiencia de Tiamina/diagnóstico , Acidosis Láctica/tratamiento farmacológico , Adenocarcinoma Mucinoso/cirugía , Adulto , Anciano , Enfermedad de Crohn/cirugía , Femenino , Humanos , Masculino , Pancreatitis/cirugía , Complicaciones Posoperatorias/tratamiento farmacológico , Neoplasias Gástricas/cirugía , Tiamina/administración & dosificación , Deficiencia de Tiamina/tratamiento farmacológico
13.
Cancer Commun ; 1(6): 337-43, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2702039

RESUMEN

We determined whether transforming growth factor-beta (TGF-beta) could be encapsulated in phospholipid liposomes and then would mediate antiproliferative activity against the sensitive, human breast cancer cell line, MDA-MB-435. TGF-beta was encapsulated in multilamellar liposomes consisting of phosphatidylcholine (PC) or PC and phosphatidylserine (PS) at a 7:3 molar ratio. It was captured in both the aqueous phase and the bilayer lipid (hydrophilic and lipophilic association) and was stable for at least 24 hr of incubation at 37 degrees C in medium that contained 5% fetal bovine serum. In calcium- and magnesium-free Hanks' balanced salt solution, TGF-beta in the internal aqueous compartment was stable for at least five days, even in the presence of trypsin and ethylenediamine tetraacetic acid. TGF-beta (type 1 or 2) in liposomes was active as free-form TGF-beta in mediation of antiproliferative effects. The lipophilic nature of TGF-beta, which resulted in a high capture ratio in liposomes, coupled with exceptional stability, suggested that liposomes could be a carrier for the in vivo use of TGF-beta.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , División Celular/efectos de los fármacos , Factores de Crecimiento Transformadores/farmacología , Relación Dosis-Respuesta a Droga , Portadores de Fármacos , Humanos , Técnicas In Vitro , Liposomas , Factores de Crecimiento Transformadores/administración & dosificación , Células Tumorales Cultivadas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...