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1.
Laryngorhinootologie ; 93(2): 87-94, 2014 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-23929209

RESUMEN

A new and interdisciplinary S2k AWMF guideline for the treatment of obstructive sialadenitis has been published. There have been several technical achievements, for instance in the field of ultrasonography, via sialendoscopy, or by MR-sialography, that have increased the possibilities for diagnosis and treatment of patients with obstructive sialadenitis. In the past, the treatment of choice in case of unsuccessful medical treatment was a complete extirpation of the affected salivary gland. Nowadays, using a variety of modern treatment options (like sialendoscopy, or extracorporeal shock-waves lithotripsy sometimes combined with salivary duct incision), it is possible in most patients, especially in cases of sialolithiasis, to preserve the affected gland. A functional recovery after gland-sparing surgery is described but more data is needed to finally evaluate the long-time results. The new guideline describes all relevant steps to diagnose an obstructive sialadenitis and values all diagnostic tools critically. Finally, all recommendable therapy options are described and valued, too.


Asunto(s)
Cálculos del Conducto Salival/terapia , Sialadenitis/terapia , Constricción Patológica/diagnóstico , Constricción Patológica/etiología , Constricción Patológica/terapia , Diagnóstico Diferencial , Endoscopía , Humanos , Litotricia , Imagen por Resonancia Magnética , Parotiditis/diagnóstico , Parotiditis/etiología , Parotiditis/terapia , Cálculos del Conducto Salival/diagnóstico , Cálculos del Conducto Salival/etiología , Conductos Salivales/cirugía , Sialadenitis/diagnóstico , Sialadenitis/etiología , Sialografía , Enfermedades de la Glándula Submandibular/diagnóstico , Enfermedades de la Glándula Submandibular/etiología , Enfermedades de la Glándula Submandibular/terapia , Ultrasonografía
2.
Cancer Invest ; 30(2): 106-13, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22250586

RESUMEN

This study investigated the IGF-1-influence on oncological relevant genes in pleomorphic adenomas. Therefore A64-tumor cells were stimulated by recombinant IGF-1. After RNA-extraction, transcript levels of hBD-1, hBD-2, hBD-3, DEFA1/3, DEFA4, S100A4, Psoriasin, DOC-1, EGF, EGFR, and IGFR were analyzed by qRT-PCR at t = 0, 4, 8, 24, 48, and 72 hr. The gene-products were visualized by immunostaining. A64-tumor-cells were deficient for hBD-1 and IGF-1. IGF-1 downregulates hBD-2 and hBD-3 without influencing hBD-1-expression. IGF-1 only slightly affects DEFA1/3-, DEFA4-, S100A4-, Psoriasin-, DOC-1-, EGF-, EGFR-, and IGFR-gene-expression. IGF-1-deficiency combined with low basic hBD-2-gene-expression and hBD-3-gene-expression might counteract, whereas hBD-1-deficiency promotes malignant transformation in pleomorphic adenomas.


Asunto(s)
Adenoma Pleomórfico/genética , Transformación Celular Neoplásica/genética , Factor I del Crecimiento Similar a la Insulina/deficiencia , Neoplasias de las Glándulas Salivales/genética , beta-Defensinas/genética , Adenoma Pleomórfico/metabolismo , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Expresión Génica , Humanos , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/farmacología , Neoplasias de las Glándulas Salivales/metabolismo , beta-Defensinas/biosíntesis , beta-Defensinas/metabolismo
3.
J Econ Entomol ; 105(5): 1659-67, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23156162

RESUMEN

The amber-marked birch leafminer (Profenusa thomsoni [Konow]) (Hymenoptera: Tenthredinidae) has caused severe infestations of birch species in Anchorage, AK, since 2002. Its spatial distribution has been monitored since 2006 and summarized using interpolated surfaces based on simple kriging. Results indicate that this insect pest is unevenly distributed, occurring in multineighborhood sized patches that migrate from year to year. Patches showing heavy infestation one year are followed by light infestations the following year. In this study, we developed methods of assessing and describing spatial distributions of P. thomsoni as they vary from year to year, and speculate on potential causes of these trends in landscape patterns.


Asunto(s)
Betula , Entomología/métodos , Himenópteros/fisiología , Especies Introducidas , Alaska , Animales , Cadena Alimentaria , Dinámica Poblacional , Estaciones del Año
4.
Nat Med ; 4(8): 909-14, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9701242

RESUMEN

Although the involvement of soluble and matrix-immobilized proteases in tumor cell invasion and metastasis is well recognized, the role of proteolytically activated cell surface receptors has not been elucidated. We report here that thrombin receptor, a member of the protease-activated receptor family, is preferentially expressed in highly metastatic human breast carcinoma cell lines and breast carcinoma biopsy specimens. Introduction of thrombin receptor antisense cDNA considerably inhibited the invasion of metastatic breast carcinoma cells in culture through a reconstituted basement membrane. During placental implantation of the human embryo, thrombin receptor is transiently expressed in the invading cytotrophoblasts. These results emphasize the involvement of thrombin receptor in cell invasion associated with tumor progression and normal embryonic development.


Asunto(s)
Neoplasias de la Mama/patología , ADN sin Sentido/farmacología , Placenta/fisiología , Receptores de Trombina/biosíntesis , Adenocarcinoma/patología , Biopsia , Mama/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma/patología , Carcinoma Ductal de Mama/patología , Línea Celular , ADN Complementario , Implantación del Embrión , Femenino , Regulación de la Expresión Génica , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/prevención & control , Embarazo , Receptores de Trombina/fisiología , Proteínas Recombinantes/biosíntesis , Transfección , Trofoblastos/fisiología , Células Tumorales Cultivadas
5.
BMC Cancer ; 8: 290, 2008 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-18840281

RESUMEN

BACKGROUND: Whereas the antimicrobial peptides hBD-2 and -3 are related to inflammation, the constitutively expressed hBD-1 might function as 8p tumour suppressor gene and thus play a key role in control of transcription and induction of apoptosis in malignant epithelial tumours. Therefore this study was conducted to characterise proteins involved in cell cycle control and host defence in different benign and malignant salivary gland tumours in comparison with healthy salivary gland tissue. METHODS: 21 paraffin-embedded tissue samples of benign (n = 7), and malignant (n = 7) salivary gland tumours as well as healthy (n = 7) salivary glands were examined immunohistochemically for the expression of p53, bcl-2, and hBD-1, -2, -3. RESULTS: HBD-1 was distributed in the cytoplasm of healthy salivary glands and benign salivary gland tumours but seems to migrate into the nucleus of malignant salivary gland tumours. Pleomorphic adenomas showed cytoplasmic as well as weak nuclear hBD-1 staining. CONCLUSION: HBD-1, 2 and 3 are traceable in healthy salivary gland tissue as well as in benign and malignant salivary gland tumours. As hBD-1 is shifted from the cytoplasm to the nucleus in malignant salivary gland tumours, we hypothesize that it might play a role in the oncogenesis of these tumours. In pleomorphic adenomas hBD-1 might be connected to their biologic behaviour of recurrence and malignant transformation.


Asunto(s)
Núcleo Celular/metabolismo , Neoplasias de las Glándulas Salivales/metabolismo , beta-Defensinas/metabolismo , Adenoma Pleomórfico/metabolismo , Carcinoma Adenoide Quístico/metabolismo , Estudios de Casos y Controles , Citoplasma/metabolismo , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Glándulas Salivales/metabolismo , Glándulas Salivales/patología , Proteína p53 Supresora de Tumor/metabolismo
6.
Int J Oral Maxillofac Surg ; 37(7): 660-3, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18346877

RESUMEN

The aim of this study was to investigate the gene expression of human beta-defensin-1, -2, -3 (hBD-1, -2, -3), interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 in oral squamous cell carcinoma (OSCC) compared to benign and premalignant lesions as well as healthy controls. Biopsies of healthy gingiva (n=5), irritation fibroma (n=5), leukoplakia (n=5) and OSCC (n=5) were obtained during routine surgical procedures. RNA was extracted according to standard protocols and transcripts of hBD-1, -2, -3, interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 were analysed by real-time polymerase chain reaction. The expression of hBD-1 was reduced in all lesions (5-fold in irritation fibroma and 2.5-fold in leukoplakia), but most significantly (50-fold) in OSCC. hBD-1 appears to play a role in the development of OSCC. The loss of its function might contribute to the malignant progression of these tumours.


Asunto(s)
Antiinfecciosos/análisis , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/patología , beta-Defensinas/análisis , Carcinoma de Células Escamosas/genética , Ciclooxigenasa 2/análisis , Progresión de la Enfermedad , Fibroma/genética , Fibroma/patología , Regulación Neoplásica de la Expresión Génica/genética , Encía/anatomía & histología , Humanos , Interleucina-1beta/análisis , Leucoplasia Bucal/genética , Leucoplasia Bucal/patología , Neoplasias de la Boca/genética , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/análisis
7.
Int J Tuberc Lung Dis ; 11(1): 113-5, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17217140

RESUMEN

A single nucleotide polymorphism (SNP), +874T/A, in the first intron of the interferon-gamma (IFN-gamma) gene, has presented associations with human susceptibility to tuberculosis (TB) in some ethnic populations, but not in others. In this population-based case-control study with adult TB patients from Houston, Texas, we found no significant differences of + 874T/A genotypic frequencies between cases and ethnically-matched controls or between advanced forms of TB disease (extra-pulmonary involvement or presence of cavitary disease) and pulmonary TB. Given possible sample size limitations, our results suggest that the IFN-gamma +874T/A mutation has no association with TB susceptibility or TB disease severity.


Asunto(s)
Predisposición Genética a la Enfermedad , Interferón gamma/genética , Polimorfismo de Nucleótido Simple , Tuberculosis/genética , Adulto , Alelos , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Texas
8.
Mol Cell Biol ; 9(5): 2133-41, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2747645

RESUMEN

The gene transfer technique was used to examine the role of plasminogen activator (PA) in the invasive and metastatic behavior of tumorigenic cells. H-ras-transformed NIH 3T3 clonal cells producing a very low level of PA were generated and further transfected with an expression plasmid containing a cDNA sequence encoding either the urokinase-type or the tissue-type human PA. Compared with the parental transformed cells, clonal cells expressing high levels of both types of recombinant PA invaded more rapidly through a basement membrane reconstituted in vitro. Furthermore, cells expressing high levels of recombinant urokinase-type PA also caused a higher incidence of pulmonary metastatic lesions after intravenous injection into nude mice. Both activities were reduced by the serine proteinase inhibitor EACA; invasion was also suppressed by antibodies blocking the activity of human PAs and by the synthetic collagenase inhibitor SC-44463. These findings provide direct genetic evidence for a causal role of PA in invasive and metastatic activities.


Asunto(s)
Transformación Celular Neoplásica , Activadores Plasminogénicos/genética , Animales , Membrana Basal/fisiología , Regulación de la Expresión Génica , Humanos , Ratones , Invasividad Neoplásica , Metástasis de la Neoplasia , Activadores Plasminogénicos/biosíntesis , Proto-Oncogenes
9.
Ophthalmologe ; 114(5): 450-456, 2017 May.
Artículo en Alemán | MEDLINE | ID: mdl-27613545

RESUMEN

BACKGROUND: Investigations have shown that the internet as a source of information in medical issues is increasing in importance. For most patients information delivered or supported by hospitals and universities is considered to be the most reliable, however, the comprehensibility of available information is often considered to be wanting. Comprehensibility scores are formulae allowing a quantitative value for the readability of a document to be calculated. OBJECTIVE: The purpose of this study was to assess data by analyzing the comprehensibility of medical information published on the websites of departments for ophthalmology of German university hospitals. We investigated and analyzed medical information dealing with three eye diseases with potentially severe irreversible damage. METHODS: The websites of 32 departments for ophthalmology of German university hospitals were investigated. Information regarding cataracts, glaucoma and retinal detachment (amotio retinae) were identified and analyzed. All information was systematically analyzed regarding comprehensibility by using the analysis program Text-Lab ( http://www.text-lab.de ) by calculation of five readability scores: the Hohenheim comprehensibility index (HVI), the Amstad index, the simple measure of gobbledygook (G-SMOG) index, the Vienna non-fictional text formula (W-STX) and the readability index (LIX). RESULTS: In 59 cases (61.46 %) useful text information from the homepage of the institutions could be detected and analyzed. On average the comprehensibility of the information was identified as being poor (HVI 7.91 ± 3.94, Amstad index 35.45 ± 11.85, Vienna formula 11.19 ± 1.93, G­SMOG 9.77 ± 1.42 and the LIX 54.53 ± 6.67). CONCLUSION: In most of the cases patient information material was written far above the literacy level of the average population. It must be assumed that the presented information is difficult to read for the majority of the patients. A critical evaluation of accessible information material seems to be desirable and available texts should be amended.


Asunto(s)
Comprensión , Instrucción por Computador/clasificación , Información de Salud al Consumidor/clasificación , Oftalmopatías , Alfabetización en Salud/clasificación , Internet , Oftalmología/educación , Centros Médicos Académicos , Alemania , Humanos , Sistemas en Línea/clasificación , Lectura
10.
J Natl Cancer Inst ; 81(8): 587-94, 1989 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-2539488

RESUMEN

The in vivo growth behavior and invasive potential of normal and "immortalized" human bronchial epithelial cells were studied by xenotransplantation procedures, an in vitro assay of invasiveness, and determinations of type IV collagenase activity and mRNA expression. BEAS-2B cells, immortalized after hybrid virus infection (adenovirus 12-simian virus 40), reconstituted a columnar epithelium when xenotransplanted into de-epithelialized rat tracheas transplanted sc into athymic BALB/c mice. A few adenomatous growths could be seen 16 weeks after transplantation. BZR cells, obtained by transfer of the v-Ha-ras oncogene into BEAS-2B cells, were tumorigenic in this xenotransplantation model. BZR-T33 cells, obtained from a tumor produced after injection of BZR cells, were also tumorigenic; however, they exhibited a shorter latent period. When these same cell lines were injected sc and iv into athymic BALB/c mice, BEAS-2B cells were not tumorigenic, and the BZR-T33 cells were more tumorigenic than the BZR cells. The incidence of spontaneous metastases after sc inoculation was zero for BEAS-2B cells, 33% for BZR cells, and 100% for BZR-T33 cells. Similar increasing values that correlated well with the data on in vivo growth were noted in the in vitro invasion assay, the collagenolytic ability, and the mRNA expression of type IV collagenase. Normal human bronchial epithelial cells showed the lowest values in all the assays. These progressive changes occurring in cells derived from the same parental line indicate that the presence of the v-Ha-ras oncogene in immortalized bronchial cells is associated with a full-fledged malignant phenotype, which is further enhanced by in vivo passaging.


Asunto(s)
Carcinoma Broncogénico/patología , Neoplasias Pulmonares/patología , Animales , Northern Blotting , Carcinoma Broncogénico/enzimología , Carcinoma Broncogénico/secundario , Línea Celular Transformada , Quimiotaxis/efectos de los fármacos , Fibronectinas/farmacología , Humanos , Immunoblotting , Neoplasias Pulmonares/enzimología , Ratones , Ratones Desnudos , Colagenasa Microbiana/metabolismo , Invasividad Neoplásica , Trasplante de Neoplasias
11.
Cancer Res ; 55(16): 3669-74, 1995 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-7543020

RESUMEN

UV radiation has been shown to play a role in the initiation of human cutaneous melanoma, but its role in the development of malignant melanoma to the metastatic state is not very well defined. Although previous studies have concentrated on the effect of UV-B on the host immune response, the effect of UV-B on the tumor cells was not elucidated. Here we show that UV-B can induce interleukin 8 (IL-8) mRNA and protein secretion in human cutaneous melanoma with negligible expression of IL-8. UV-B-induced IL-8 was constitutively expressed 60 days after irradiation in tumors implanted in mice. Induction of IL-8 was UV-B dose dependent and blocked by cyclohexamide, indicating that de novo protein synthesis is required for its expression. The UV-irradiated cells demonstrated enhanced tumorigenicity and metastatic potential in nude mice. The increase in tumorigenicity and metastatic ability could be explained by the increase in Mr 72,000 type IV collagenase activity and angiogenesis attributed to the induction of IL-8 after irradiation. The acquisition of the metastatic phenotype induced by UV-B could not be attributed to abnormalities in the p53 or MTS-1 (p16INK4) genes. To the best of our knowledge, this is the first report to show that UV-B can increase the aggressiveness of human cutaneous melanoma for growth and metastasis.


Asunto(s)
Interleucina-8/biosíntesis , Melanoma/patología , Neoplasias Cutáneas/patología , Rayos Ultravioleta , Animales , Proteínas Portadoras/genética , Colagenasas/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Cicloheximida/farmacología , Relación Dosis-Respuesta en la Radiación , Regulación Neoplásica de la Expresión Génica , Genes p53 , Técnicas In Vitro , Neoplasias Pulmonares/secundario , Masculino , Metaloproteinasa 9 de la Matriz , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia , Trasplante de Neoplasias , Neovascularización Patológica , ARN Mensajero/genética , Células Tumorales Cultivadas
12.
Cancer Res ; 57(11): 2295-303, 1997 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9187135

RESUMEN

The cell surface adhesion molecule MCAM (MUC18) is strongly expressed by advanced primary and metastatic melanomas but is weaker and less frequent in nevus cells. Previous studies have shown that MCAM expression correlates with tumor thickness and metastatic potential of human melanoma cells in nude mice. To provide direct evidence that MCAM plays a role in tumor growth and metastasis of human melanoma, the nonmetastatic MCAM-negative primary cutaneous melanoma SB-2 cells were transfected with MCAM cDNA and analyzed subsequently for changes in their tumorigenic and metastatic potential. Enforced expression of MCAM in SB-2 cells rendered them highly tumorigenic and increased their metastatic potential in nude mice as compared with parental and control transfected cells. The transfected cells displayed increased homotypic adhesion, increased attachment to human endothelial cells, decreased ability to adhere to laminin, and increased invasiveness through Matrigel-coated filters. Anti-MCAM monoclonal antibody reversed these functions in the transfected cells but not in control cells. The above changes in function attributed to the expression of MCAM may underlie the contribution of MCAM/MUC18 to the malignant phenotype.


Asunto(s)
Antígenos CD , Regulación Neoplásica de la Expresión Génica , Melanoma/genética , Melanoma/patología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Moléculas de Adhesión de Célula Nerviosa , Animales , Anticuerpos Bloqueadores/inmunología , Antígeno CD146 , Adhesión Celular/genética , División Celular/genética , ADN Complementario/genética , Humanos , Laminina/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia/genética , Transfección , Células Tumorales Cultivadas
13.
Cancer Res ; 48(23): 6764-8, 1988 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-2846159

RESUMEN

Estrogen increases the ability of the estrogen-dependent MCF-7 human breast cancer cell line to both proliferate and invade through an artificial basement membrane. In studying the response of MCF-7 cells to various antiestrogens, we found that 4-hydroxytamoxifen and tamoxifen inhibited cell proliferation but increased their invasiveness. In contrast, the structurally unrelated benzothiophene antiestrogens, LY117018 and LY156758, were potent antiproliferative agents which did not stimulate invasiveness. The differential effects of these antiestrogenic agents on invasion correlated with changes in production of collagenase IV, while no significant change was seen in the chemotactic activity of the cells. Invasiveness was increased by 17 beta-estradiol or 4-hydroxytamoxifen after a few hours of treatment and was rapidly lost when 17 beta-estradiol was withdrawn. Stimulation of invasiveness with 17 beta-estradiol was blocked by the antiestrogen, LY117018. Cells from the MDA-MB-231 line which lacks estrogen receptors were not affected by estrogen or antiestrogen in terms of proliferation or invasion. These studies indicate that the invasiveness of MCF-7 cells is regulated by antiestrogens through the estrogen receptor and may be mediated by collagenase IV activity. Antiestrogens which reduce both the proliferation and invasiveness of these cells may be interesting new candidates for clinical application.


Asunto(s)
Neoplasias de la Mama/patología , Antagonistas de Estrógenos/farmacología , Invasividad Neoplásica , División Celular/efectos de los fármacos , Quimiotaxis , Estradiol/farmacología , Femenino , Humanos , Colagenasa Microbiana/biosíntesis , Activadores Plasminogénicos/biosíntesis , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacología , Células Tumorales Cultivadas
14.
Cancer Res ; 48(12): 3307-12, 1988 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-2836052

RESUMEN

Using both human and murine cell lines, we show that malignant cells are able to invade through basement membrane and also secrete elevated amounts of collagenase IV, an enzyme implicated in the degradation of basement membranes. Using serine proteinase inhibitors and antibodies to plasminogen activators as well as a newly described collagenase inhibitor we demonstrate that a protease cascade leads to the activation of an enzyme(s) that cleaves collagen IV. Inhibition at each step reduces the invasion of the tumor cells through reconstituted basement membrane in vitro. Treatment with a collagenase inhibitor reduced the incidence of lung lesions in mice given i.v. injections of malignant melanoma cells.


Asunto(s)
Membrana Basal/patología , Colagenasa Microbiana/antagonistas & inhibidores , Invasividad Neoplásica , Activadores Plasminogénicos/antagonistas & inhibidores , Inactivadores Plasminogénicos , Inhibidores de Serina Proteinasa , Animales , Activación Enzimática , Humanos , Ratones , Colagenasa Microbiana/fisiología , Activadores Plasminogénicos/fisiología , Serina Endopeptidasas/fisiología , Células Tumorales Cultivadas
15.
Cancer Res ; 49(16): 4615-21, 1989 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-2545347

RESUMEN

In a series of immortalized human bronchial epithelial cell lines continuing various oncogenes, the transcriptional levels of the type IV collagenase and the type IV procollagen genes were compared with the properties of invasiveness in vitro and tumorigenicity and metastatic ability in athymic nude mice. v-Ha-ras greatly enhanced invasion and metastasis, whereas v-Ki-ras, c-myc, and c-raf had lesser effects on these malignant phenotypes. In addition, cell lines derived from tumors obtained by injecting the original immortalized human bronchial epithelial cell lines into nude mice exhibited enhanced invasive and metastatic abilities and increased level of type IV collagenase mRNA when compared with the original immortalized human bronchial epithelial cell lines. Invasiveness and metastatic capacity correlated positively with expression of the type IV collagenase gene and negatively with the expression of the type IV procollagen gene, suggesting that these phenotypes are associated both with decreased production and increased dissolution of extracellular matrix.


Asunto(s)
Bronquios , Transformación Celular Neoplásica/genética , Genes , Neoplasias Pulmonares/patología , Colagenasa Microbiana/genética , Procolágeno/genética , Animales , Línea Celular , Transformación Celular Neoplásica/enzimología , Transformación Celular Neoplásica/patología , Quimiotaxis , Células Epiteliales , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatología , Ratones , Metástasis de la Neoplasia , Oncogenes , Factores de Tiempo , Transcripción Genética
16.
Cancer Res ; 58(4): 808-14, 1998 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-9485039

RESUMEN

The purpose of these studies was to determine whether systemic administration of IFN-alpha can inhibit the expression of basic fibroblast growth factor (bFGF) in human transitional cell carcinoma, reduce its angiogenesis, and thus inhibit its growth in the bladder wall of nude mice. In vitro incubation of the highly metastatic 253J B-V cells and the IFN-alpha-resistant 253J B-V IFNR cells with noncytostatic concentrations of IFN-alpha down-regulated the steady-state mRNA transcripts and protein production of bFGF. IFN-alpha-insensitive and IFN-alpha-resistant cells were implanted in the bladder wall of nude mice. Systemic administration of IFN-alpha decreased the in vivo expression of bFGF, decreased blood vessel density in the tumors, and inhibited tumor growth of both IFN-alpha-insensitive and IFN-alpha-resistant cells. These data suggest that in addition to its well-documented antiproliferative effects, IFN-alpha can inhibit the growth of human bladder cancer cells by inhibition of angiogenesis.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/metabolismo , Interferón-alfa/farmacología , Neovascularización Patológica , Animales , Carcinoma de Células Transicionales/irrigación sanguínea , Carcinoma de Células Transicionales/metabolismo , Regulación hacia Abajo , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , ARN Mensajero/metabolismo , Trasplante Heterólogo , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/irrigación sanguínea , Neoplasias de la Vejiga Urinaria/metabolismo
17.
Oncogene ; 5(1): 75-83, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2157183

RESUMEN

Stable transfection of human tumor cell lines with the adenovirus-5 E1A gene repressed the expression of the secreted proteases, type IV collagenase, interstitial collagenase and urokinase. In addition, E1A blocked the 12-O-tetradecanoyl phorbol acetate (TPA) induction of interstitial collagenase transcription in HT1080 fibrosarcoma cells. Plasmids bearing the interstitial collagenase or type IV collagenase 5' flanking regions linked to a chloramphenicol acetyl transferase coding sequence were constructed and analysed for expression by transient cotransfections into HT1080 cells. Cotransfection with a plasmid bearing a functional E1A gene repressed transcription of the type IV collagenase promoter and blocked the TPA induction of the interstitial collagenase promoter. Furthermore, E1A repressed transcription from a TK promoter driven by AP-1 complex binding sites (TRE), suggesting that E1A interferes with the AP-1 trans-activation pathway. This effect was not, however, due to the repression of c-jun gene transcription by E1A. In fact, the expression of E1A rendered the c-jun gene hypersensitive to TPA induction. Concomitant with reduction in expression levels of secreted proteases, stable E1A transfectants showed reduced metastatic activity in vivo and reduced ability to traverse a reconstituted basement membrane in vitro. Monospecific anti-type IV collagenase antibodies inhibited invasive activity of parental tumor cell lines in the in vitro assay, suggesting a possible causal relationship between the repression of secreted proteases and loss of metastatic properties of the transformants.


Asunto(s)
Expresión Génica , Metástasis de la Neoplasia , Proteínas Oncogénicas Virales/fisiología , Péptido Hidrolasas/genética , Proteínas Precoces de Adenovirus , Secuencia de Bases , Transformación Celular Neoplásica , Cloranfenicol O-Acetiltransferasa/análisis , Cloranfenicol O-Acetiltransferasa/genética , Proteínas de Unión al ADN/genética , Humanos , Metaloendopeptidasas/genética , Colagenasa Microbiana/genética , Datos de Secuencia Molecular , Invasividad Neoplásica , Péptido Hidrolasas/fisiología , Proteínas Proto-Oncogénicas c-jun , Proto-Oncogenes , Acetato de Tetradecanoilforbol/farmacología , Factores de Transcripción/genética , Transcripción Genética , Transfección
18.
Biochim Biophys Acta ; 1139(1-2): 77-83, 1992 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-1319214

RESUMEN

Basement membrane-degrading enzymes of two clonal sublines of the murine Lewis lung carcinoma with distinct patterns of organ-selective metastasis were analyzed. Subline M-27 is highly metastatic to the lung and does not form liver metastases, while subline H-59 is highly metastatic to lymph nodes and liver, but not to lung. Qualitative and quantitative differences in the enzymatic profiles were found. H-59 cells which were significantly more invasive in vitro in the Matrigel invasion assay were found by zymogram analysis to secrete high levels of a 72 kDa gelatinase, while M-27 cells produced low levels of this gelatinase and of a higher molecular weight species which migrated in the 107 kDa region. On the other hand, M-27 cells produced significantly higher levels of urokinase type plasminogen activator (uPA) as indicated by a fibrinolysis assay and by Western blot analysis. Northern blot assays revealed an increase of approx. 3-fold in mRNA for cathepsin B in tumor M-27 which was reflected in a quantitative difference in plasma membrane cathepsin B levels as detected by Western blot analysis. H-59 cells on the other hand expressed approx. 8.5-fold more mRNA for cathepsin L. The quantitative differences in the levels of basement membrane degrading proteinases released by these tumor cells suggest that invasion by these cells is differentially regulated--a possible factor in their distinct patterns of dissemination.


Asunto(s)
Membrana Basal/enzimología , Neoplasias Hepáticas Experimentales/enzimología , Neoplasias Pulmonares/enzimología , Animales , Western Blotting , Catepsinas/metabolismo , Gelatinasas , Neoplasias Hepáticas Experimentales/secundario , Neoplasias Pulmonares/secundario , Metaloproteinasa 9 de la Matriz , Ratones , Colagenasa Microbiana , Invasividad Neoplásica , Pepsina A , Activadores Plasminogénicos/metabolismo , Serina Endopeptidasas/metabolismo , Células Tumorales Cultivadas
19.
Biochim Biophys Acta ; 449(2): 285-94, 1976 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-990296

RESUMEN

The comparison of light-induced absorption changes in photosynthesis with electrochromic spectra of the isolated pigments in vitro is renewed more thoroughly and described in detail, involving new measurements of the linear electrochromism of oriented chlorophyll beta [6]. 1. The coincidence of the maxima and minima in the in vivo spectrum with those in the in vitro superposition is better than in previous studies [4]. 2. The molar ratio of the pigments now used for the superposition of the in vitro spectra is the same as that in vivo. 3. From this and from surface-pressure/area diagrams of the chlorophylls on a water surface, conclusions are drawn concerning the preferential orientations of the dipole moment differences of the red and blue absorption bands of the bulk chlorophylls in the membrane. 4. From the comparison of the electrochromism of the carotenoids with the absorption change at 520 nm in vivo, it is concluded that the bulk of the carotenoids are oriented at a rather flat angle in the membrane (approximately 16 degrees).


Asunto(s)
Membrana Celular/ultraestructura , Membranas Artificiales , Fotosíntesis , Carotenoides/análisis , Membrana Celular/fisiología , Clorofila/fisiología , Colorantes , Electroquímica , Matemática , Modelos Biológicos , Presión , Espectrofotometría , Espectrofotometría Ultravioleta , Propiedades de Superficie
20.
Clin Cancer Res ; 5(8): 1982-8, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10473075

RESUMEN

Matrix metalloproteinase-2 (MMP-2) plays a critical role in tumor cell invasion and metastasis. Inhibitors of this enzyme effectively suppress tumor metastasis in experimental animals and are currently being tested in clinical trials. MMP-2 transcriptional regulation is a part of a delicate balance between the expression of various extracellular matrix (ECM) constituents and ECM degrading enzymes. Halofuginone, a low-molecular-weight quinazolinone alkaloid, is a potent inhibitor of collagen type alpha1 (I) gene expression and ECM deposition. We now report that expression of the MMP-2 gene by murine (MBT2-t50) and human (5637) bladder carcinoma cells is highly susceptible to inhibition by halofuginone. Fifty percent inhibition was obtained in the presence of as little as 50 ng/ml halofuginone. This inhibition is due to an effect of halofuginone on the activity of the MMP-2 promoter, as indicated by a pronounced suppression of chloramphenicol acetyltransferase activity driven by the MMP-2 promoter in transfected MBT2 cells. There was no effect on chloramphenicol acetyltransferase activity driven by SV40 promoter in these cells. Halofuginone-treated cells failed to invade through reconstituted basement-membrane (Matrigel) coated filters, in accordance with the inhibition of MMP-2 gene expression. A marked reduction (80-90%) in the lung colonization of MBT2 bladder carcinoma cells was obtained after the i.v. inoculation of halofuginone-treated cells as compared with the high metastatic activity exhibited by control untreated cells. Under the same conditions, there was almost no effect of halofuginone on the rate of MBT2 cell proliferation. These results indicate that the potent antimetastatic activity of halofuginone is due primarily to a transcriptional suppression of the MMP-2 gene, which results in a decreased enzymatic activity, matrix degradation, and tumor cell extravasation. This is the first description, to our knowledge, of a drug that inhibits experimental metastasis through the inhibition of MMP-2 at the transcriptional level. Combined with its known inhibitory effect on collagen synthesis and ECM deposition, halofuginone is expected to exert a profound anticancerous effect by inhibiting both the primary tumor stromal support and metastatic spread.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma/enzimología , Inhibidores de la Metaloproteinasa de la Matriz , Quinazolinas/farmacología , Neoplasias de la Vejiga Urinaria/enzimología , Animales , Carcinoma/metabolismo , Carcinoma/secundario , Colágeno , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Gelatina/metabolismo , Humanos , Laminina , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C3H , Invasividad Neoplásica , Trasplante de Neoplasias , Piperidinas , Regiones Promotoras Genéticas/efectos de los fármacos , Proteoglicanos , Quinazolinonas , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología
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