Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Anaesthesia ; 77(10): 1106-1112, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35918788

RESUMEN

The interscalene brachial plexus block is recommended for analgesia after shoulder surgery but it may cause hemidiaphragmatic dysfunction. We tested whether ipsilateral hemidiaphragmatic contraction was better after a smaller dose of local anaesthetic without impairing analgesic effect. We randomly allocated 48 adults to 10 ml or 20 ml levobupivacaine 0.25% before arthroscopic shoulder surgery. The primary outcome was hemidiaphragmatic paralysis, defined as inspiratory thickness < 1.2 times expiratory thickness, measured by ultrasound 4 h after block. Hemidiaphragmatic paralysis was recorded for 6/24 vs. 23/24 supine participants after 10 ml vs. 20 ml levobupivacaine 0.25%, respectively, and for 4/24 vs. 23/24 sitting participants, respectively, p < 0.001 for both. Pain scores after 10 ml injectate were not worse than after 20 ml injectate. Median (IQR [range]) morphine doses in the first 24 postoperative hours after 10 ml and 20 ml levobupivacaine 0.25% were 2 (0-6 [0-23]) mg vs. 1 (0-2 [0-11]) mg, respectively, p = 0.12. No participant had a complication after 10 ml interscalene levobupivacaine, whereas seven had complications after 20 ml levobupivacaine, p = 0.009. Hemidiaphragmatic function was better after 10 ml vs. 20 ml interscalene levobupivacaine 0.25% without impairing analgesia for 24 postoperative hours.


Asunto(s)
Bloqueo del Plexo Braquial , Adulto , Anestésicos Locales , Artroscopía , Humanos , Levobupivacaína , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Parálisis , Hombro/cirugía
2.
Trials ; 22(1): 287, 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33874993

RESUMEN

BACKGROUND: Arthroscopic shoulder surgery causes severe postoperative pain. An interscalene brachial plexus block provides adequate analgesia, but unintended spread of the local anesthetic administered may result in a phrenic nerve block, usually associated with a nonnegligible incidence of acute hemidiaphragmatic paralysis. The main purpose of this trial will be to analyze the incidence of hemidiaphragmatic paralysis ensuing after interscalene brachial plexus block in patients undergoing arthroscopic shoulder surgery administered a standard volume (20 ml) vs. a low volume (10 ml) of levobupivacaine 0.25%. METHODS: This will be a prospective double-blind randomized controlled single-center two-arm comparative trial. Forty-eight patients will be included. The primary goal will be to ultrasonographically determine the incidence of hemidiaphragmatic paralysis by calculating the diaphragmatic thickness ratio in each group. The secondary goals will be to compare the two arms in terms of (1) decrease in forced vital capacity and (2) in forced expiratory volume at 1 s by spirometry; (3) decrease in diaphragmatic excursion by ultrasound; (4) 24-h total intravenous morphine consumption; (5) time to first opioid request of a patient-controlled analgesia pump; and (6) postoperative complications. DISCUSSION: This trial will demonstrate that a low-volume interscalene brachial plexus block decreases hemidiaphragmatic paralysis following arthroscopic shoulder surgery according to spirometry and ultrasound measurements and does not provide inferior postoperative analgesia to the standard volume, as measured by opioid requirements. TRIAL REGISTRATION: EudraCT and Spanish Trial Register (REec) registration number: 2019-003855-12 (registered on 7 January 2020). ClinicalTrials.gov identification number: NCT04385966 (retrospectively registered on 8 May 2020). Ethics Committee approval: EC19/093 (18 December 2019).


Asunto(s)
Bloqueo del Plexo Braquial , Parálisis Respiratoria , Anestésicos Locales/efectos adversos , Artroscopía/efectos adversos , Bloqueo del Plexo Braquial/efectos adversos , Método Doble Ciego , Humanos , Levobupivacaína , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Parálisis , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Parálisis Respiratoria/diagnóstico , Parálisis Respiratoria/diagnóstico por imagen , Hombro
3.
J Natl Cancer Inst ; 87(20): 1524-9, 1995 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-7563186

RESUMEN

BACKGROUND: Two genes, p16 (also known as CDKN2, INK4A, or MTS1) and p15 (also described as INK4B or MTS2), are found in tandem at chromosome 9p21. These genes are designated as candidate tumor suppressor genes because they encode proteins that function as negative cell cycle regulators. (The encoded polypeptides inactivate specific cyclin-protein kinase complexes that are required for progression through the cell cycle.) Molecular genetic studies have revealed that deletion of the p16 and p15 genes occurs frequently in cancer cell lines and in certain malignant neoplasms. PURPOSE: We evaluated the frequency of p16 and p15 gene alterations in a well-characterized cohort of human transitional cell bladder cancers, and we explored potential associations between alterations in these genes and tumor stage and/or grade. METHODS: Tumor tissue and normal tissue from 110 patients with transitional cell carcinoma of the urinary bladder were examined. The status of the p16 and p15 genes in these tissues was determined by Southern blotting and hybridization with gene-specific probes, by coupled polymerase chain reaction and single-strand conformation polymorphism analysis (PCR-SSCP), and by sequencing DNA fragments produced during PCR. Associations between alterations in the genes and tumor stage and/or grade were evaluated using the two-tailed Fisher's exact test. RESULTS: Homozygous deletion (both alleles lost) of the p16 and the p15 genes was observed in 11 and nine bladder tumors, respectively. Eight of the 11 tumors exhibiting complete loss of the p16 gene also displayed homozygous deletion of the p15 gene. Exclusive loss of either gene was detected in only three tumors. Hemizygous deletion (one allele lost, also referred to as loss of heterozygosity [LOH] of the p16 and/or p15 genes was observed in eight tumors. Rearrangement of the two genes was indicated in three additional tumors. No point mutations were identified in either gene. The overall frequency of alteration in this cohort of bladder tumors was approximately 18% for each gene (in 20 [18.3%, 95% confidence interval (CI) = 11.1%-25.6%] of 109 informative tumors for the p16 gene and in 18 [18%, 95% CI = 10.5%-25.5%] of 100 informative tumors for the p15 gene). A statistically significant association between p16 gene alteration and bladder tumors of low stage (P < .01) and grade (P < .01) was observed; a significant association between p15 gene alteration and tumors of low stage (P < .01) was also detected. CONCLUSIONS: Alteration of the p16 and p15 genes, especially coincident homozygous deletion, appears to be a common event in bladder cancer.


Asunto(s)
Carcinoma de Células Transicionales/genética , Cromosomas Humanos Par 9/genética , Quinasas Ciclina-Dependientes/genética , Eliminación de Gen , Neoplasias de la Vejiga Urinaria/genética , Anciano , Secuencia de Bases , Southern Blotting , Carcinoma de Células Transicionales/patología , Femenino , Reordenamiento Génico , Genes Supresores de Tumor , Heterocigoto , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Neoplasias de la Vejiga Urinaria/patología
4.
Clin Cancer Res ; 3(1): 81-5, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9815541

RESUMEN

Prostate-specific membrane antigen is a type II membrane protein with folate hydrolase activity produced by prostatic epithelium. The expression of this molecule has also been documented in extraprostatic tissues, including small bowel and brain. In the present study, an extensive immunohistochemical analysis was performed on a panel of well-characterized normal and malignant human tissues to further define the pattern of prostate-specific membrane antigen (PSMA) expression. Detectable PSMA levels were identified in prostatic epithelium, duodenal mucosa, and a subset of proximal renal tubules. A subpopulation of neuroendocrine cells in the colonic crypts also exhibited PSMA immunoreactivity. All other normal tissues, including cerebral cortex and cerebellum, had undetectable levels of PSMA. Thirty-three of 35 primary prostate adenocarcinomas and 7 of 8 lymph node metastases displayed tumor cell PSMA immunostaining. Eight of 18 prostate tumors metastatic to bone expressed PSMA. All of the other nonprostatic primary tumors studied had undetectable PSMA levels. However, intense staining was observed in endothelial cells of capillary vessels in peritumoral and endotumoral areas of certain malignancies, including 8 of 17 renal cell carcinomas, 7 of 13 transitional cell carcinomas, and 3 of 19 colon carcinomas. Extraprostatic PSMA expression appears to be highly restricted. Nevertheless, its diverse anatomical distribution implies a broader functional significance than previously suspected. The decrease in PSMA immunoreactivity noted in advanced prostate cancer suggests that expression of this molecule may be linked to the degree of tumor differentiation. The neoexpression of PSMA in endothelial cells of capillary beds in certain tumors may be related to tumor angiogenesis and suggests a potential mechanism for specific targeting of tumor neovasculature.


Asunto(s)
Antígenos de Neoplasias/biosíntesis , Antígenos de Superficie , Carboxipeptidasas/biosíntesis , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Glutamato Carboxipeptidasa II , Humanos , Inmunohistoquímica , Masculino , Próstata/patología , Neoplasias de la Próstata/patología , Distribución Tisular
5.
Clin Cancer Res ; 3(4): 531-6, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9815716

RESUMEN

Bilharzial-related bladder carcinoma (BBC) is the most common malignant neoplasm in Egypt, also occurring with a high incidence in other regions of the Middle East and East Africa. The clinical and pathological features of BBC are different than those described for the conventional transitional cell carcinoma of the bladder, including the high incidence of squamous cell carcinoma reported in BBC and the fact that over 90% of BBC cases at presentation are advanced-stage tumors (P3 and P4). This study was conducted to better define the phenotypic alterations associated with BBC affecting the p53 cell cycle control pathway, including altered patterns of expression of downstream effector proteins such as mdm2 and p21/WAF1. A well-characterized cohort of 125 patients affected with bilharzial-related bladder tumors was studied. Tumors were classified as squamous carcinomas (n = 68), transitional cell carcinomas (n = 55), or adenocarcinomas (n = 2). The products encoded by TP53, mdm2, and p21/WAF1 genes were analyzed by immunohistochemistry. Furthermore, the patterns of expression of these molecules were correlated with the Ki67 proliferative index. In addition, the microanatomical distribution of programmed cell death was assessed in a subset of tumors, using the so-called terminal deoxynucleotidyl transferase-mediated nick end labeling method. p53 nuclear overexpression was identified in 25 (20%) of 125 cases. Nuclear overexpression of mdm2 was detected in 74 (59.2%) of 125 cases. There was a statistically significant association between coexpression of both p53 and mdm2 and detection of lymph node metastases (P = 0.04). p21/WAF1 expression was detected in 87 (72%) of 121 evaluable cases. A high Ki67 proliferative index was observed in 99 (86%) of 115 evaluable cases. There was a statistically significant association between high Ki67 proliferative index and mdm2-positive phenotype (P = 0.005) and deep muscle invasion (P3b; P = 0.026) as well as lymph node metastases (P = 0.039). Apoptosis was observed in terminally differentiated tumor cells identified in the superficial layers of well-differentiated squamous carcinoma or exfoliating cells in transitional lesions. However, only rare apoptotic tumor cells were found in basal or suprabasal layers as well as in the invasive elements of the neoplasms studied. These results suggest that the frequency of p53 nuclear overexpression in BBC is lower than that reported for conventional transitional cell carcinoma. Nevertheless, tumors with p53 alterations have a greater propensity to progress. The prominent number of cases displaying an mdm2-positive phenotype suggests that this may be an early incident in BBC and should be regarded as a potential oncogenic phenomenon. This is supported by the significant correlation between high Ki67 proliferative index and mdm2 overexpression. The association of an aggressive clinical course with the coexpression of both p53 and mdm2 products might be viewed as a cooperative effect that develops in tumor progression.


Asunto(s)
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Transicionales/genética , Genes p53 , Proteínas Nucleares , Esquistosomiasis/complicaciones , Esquistosomiasis/genética , Neoplasias de la Vejiga Urinaria/etiología , Neoplasias de la Vejiga Urinaria/genética , Adenocarcinoma/epidemiología , Adenocarcinoma/etiología , Adenocarcinoma/patología , Adulto , Anciano , Apoptosis , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Transicionales/epidemiología , Carcinoma de Células Transicionales/etiología , Carcinoma de Células Transicionales/patología , Ciclo Celular , Estudios de Cohortes , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , Egipto/epidemiología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunofenotipificación , Etiquetado Corte-Fin in Situ , Incidencia , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-mdm2 , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/patología
6.
Rev Esp Anestesiol Reanim ; 52(2): 105-8, 2005 Feb.
Artículo en Español | MEDLINE | ID: mdl-15765992

RESUMEN

Mastocytosis is a heterogeneous grouping of entities characterized by proliferation of mast cells in one or more organs or tissues. The skin is the most frequently affected organ, followed by bone marrow. The relevance of this disease to anesthesia lies in the fact that many drugs used can trigger massive release of chemical mediators of mast cells. We report the case of a patient diagnosed with cutaneous mastocytosis who underwent testicular biopsy with intradural anesthesia. We review the fundamental aspects of the disease and the principles of anesthetic management.


Asunto(s)
Anestesia , Mastocitosis Cutánea , Adulto , Anestesia/métodos , Humanos , Masculino , Factores de Riesgo
7.
Lung Cancer ; 10(3-4): 209-19, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7521264

RESUMEN

The prognostic value of clinical and pathological factors in 97 patients with non-small cell lung cancer (NSCLC), were analyzed through immunohistochemical methods. The impact on response rate and survival of age, Karnofsky performance status (PS), sex, NSCLC subtype and grade, extent of disease, objective chemotherapy response, LDH values, metastatic sites involved and immunohistochemical markers of neuroendocrine differentiation (neuron specific enolase (NSE), synaptophysin (Sy 38), chromogranin (Chr A) and Leu-7) were analyzed. Median age was 61 years and seven patients were women. Histologically, 58 had squamous cell carcinoma, 28 adenocarcinoma and 11 large cell undifferentiated carcinoma. One patient had Stage II, 35 Stage IIIa, 19 Stage IIIb and 42 Stage IV. Six patients achieved complete response, 18 partial response, 34 stable disease and 39 progressive disease. NSE was negative in 54.3% of cases as was Sy 38 (77.4%), Chr A (97.8%) and Leu-7 (95.8%). We have found correlation between neuroendocrine differentiation and absence of P-Glycoprotein expression; patients included in this subset had a higher response rate but no evidence of longer survival. The univariate analysis showed that four parameters had significant adverse effect on survival: non-responders, poor PS, abnormal LDH value and absence of NSE expression. Multivariate analysis showed that the best combination of independent prognostic factors in predicting survival was: PS and NSE expression by immunohistochemical methods.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Adulto , Anciano , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Antígenos CD57 , Carcinoma de Pulmón de Células no Pequeñas/química , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/terapia , Diferenciación Celular , Cromogranina A , Cromograninas/análisis , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Epirrubicina/administración & dosificación , Femenino , Humanos , Ifosfamida/administración & dosificación , Factores Inmunológicos/uso terapéutico , Interferones/uso terapéutico , Estado de Ejecución de Karnofsky , Tablas de Vida , Neoplasias Pulmonares/química , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Análisis Multivariante , Proteínas de Neoplasias/análisis , Estadificación de Neoplasias , Fosfopiruvato Hidratasa/análisis , Pronóstico , Modelos de Riesgos Proporcionales , Inducción de Remisión , Estudios Retrospectivos , Tasa de Supervivencia , Sinaptofisina/análisis , Vindesina/administración & dosificación
8.
J Clin Pathol ; 51(2): 134-7, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9602687

RESUMEN

AIMS: To assess whether standard and variant isoforms of CD44 (CD44s, CD44v5, and CD44v6) have a differential expression profile in early versus advanced gastric adenocarcinoma of the diffuse and intestinal types and their metastases. METHODS: Immunohistochemical expression of CD44s, CD44v5, and CD44v6 was evaluated in 14 early gastric cancers (nine intestinal and five diffuse) and 37 advanced adenocarcinomas (21 intestinal and 16 diffuse) as well as in 18 cases of perigastric lymph node metastasis. Ten normal and five metaplastic gastric mucosa samples were also included in the study. RESULTS: Although no significant association was found between the degree of invasion and the CD44 expression profile, CD44v6 positivity was detected more frequently in metastases of intestinal-type carcinomas (66%) than in metastases of diffuse-type neoplasms (11%) (p < 0.05). Weak CD44s, CD44v5, and CD44v6 expression was observed focally in both normal and metaplastic gastric mucosa samples. CONCLUSIONS: These data suggest that CD44v6 expression may be involved in the production of lymph node metastases in intestinal-type gastric carcinoma but not in the diffuse-type disease, the metastatic potential of which is most likely unrelated to the CD44 family of adhesion molecules.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/secundario , Antígenos de Neoplasias/metabolismo , Receptores de Hialuranos/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Mucosa Gástrica/metabolismo , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , Persona de Mediana Edad
9.
Oncol Rep ; 3(4): 781-5, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21594455

RESUMEN

The prognostic value of clinical and pathological factors in 97 patients (pts) with non-small cell lung cancer (NSCLC), were analyzed through immunohistochemical methods. The impact on response rate and survival of age, Karnofsky performance status (PS), sex, NSCLC subtype and grade, extent of disease, objective chemotherapy response, LDH values, metastatic sites involved and immunohistochemical study of epidermal growth factor receptor (EGF-r), transforming growth factor alpha (TGF-alpha) and P-glycoprotein (Pgp) employing two monoclonal antibodies: C-219 and JSB-1, were analyzed. Median age was 61 years, seven pts were women. Histologically, 58 had squamous cell carcinoma, 28 adenocarcinoma and 11 large cell undifferentiated carcinoma. One patient had stage II, 35 stage IIIA, 19 stage IIIB and 42 stage IV. Six pts achieved complete response, 18 partial response, 34 stable disease and 39 progressive disease. EGF-r was positive in 30 cases, TGF-alpha in 51, C-219 Pgp in 13 and JSB-1 Pgp in 35 cases. The univariate analysis showed that 4 parameters had significant adverse effect on survival: non-responders, poor PS, abnormal LDH value and absence of EGF-r expression. On the other hand, we found no correlation between TOP-alpha and EGF-r immunostaining. But 22 pts expressed both autocrine markers and these pts had a worse median survival time. Multivariate analysis showed that the only independent prognostic factor in predicting survival was Karnofsky performance status.

13.
Rev Clin Esp ; 194(1): 23-5, 1994 Jan.
Artículo en Español | MEDLINE | ID: mdl-8153410

RESUMEN

Two patients with advanced atherosclerotic vascular disease developed multiple cholesterol emboli. In both patients the clinical presentation included livedo reticularis of the lower part of the body and purple toes with small areas of distal necrosis and ulceration. The predisposing factors are operative vascular procedures and the use of anticoagulants respectively. Biopsy of skin lesions revealed characteristic cholesterol clefts within atheromatous debris filling small, deep arterial lumen. Multiple cholesterol emboli should be suspected in presence of cutaneous lesions and confirmed histologically in the appropriate clinical setting.


Asunto(s)
Embolia por Colesterol/diagnóstico , Anciano , Femenino , Humanos , Masculino
14.
Cancer ; 67(10): 2448-53, 1991 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-1707745

RESUMEN

Preclinical data from studies of human lung cancer xenografts suggest that the cytotoxic effects of cisplatin are enhanced by alpha-interferon. To verify the above observations, the authors initiated a Phase II trial in advanced non-small cell lung cancer (NSCLC). Cisplatin was given at 100 mg/m2 during a 28-day cycle in a divided day 1 and day 8 schedule. Starting on day 1, alpha-2B interferon was administered intramuscularly at a dose of 5 million units three times a week continuously for a minimum of 2 months. Between January 1989 and September 1989, 30 patients were evaluated for response and toxicity. According to the staging system proposed by Mountain, 20 patients had Stage IV disease, 7 had Stage IIIB disease, and 3 had Stage IIIA disease. Expression of neuron-specific enolase (NSE) and Leu-7 was immunohistochemically investigated to evaluate possible relationship to treatment response. The response rate was 13.3% (95% confidence interval [CI]: 1.2% to 25%). The four responders showed positivity for NSE, and two of them were positive for Leu-7. An average of three cycles was given. The mean dose intensity administered was 83% of the projected dose for cisplatin and 92% of the projected dose for alpha-2B interferon. A standard scale was used to assess interferon toxicity. Hematologic, renal, and systemic side effects were not significant. In advanced NSCLC the addition of alpha-2B interferon did not increase the cisplatin-induced response rate. Further studies should be performed to determine the real value of chemotherapy response in tumors showing positive immunoreactivity for neural markers such as NSE and Leu-7.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Adulto , Anciano , Antígenos de Diferenciación/análisis , Antígenos CD57 , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/secundario , Cisplatino/uso terapéutico , Esquema de Medicación , Evaluación de Medicamentos , Femenino , Humanos , Técnicas para Inmunoenzimas , Interferón gamma/efectos adversos , Interferón gamma/uso terapéutico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Fosfopiruvato Hidratasa/metabolismo , Proyectos Piloto , Proteínas Recombinantes , Tasa de Supervivencia
15.
Int J Cancer ; 75(6): 819-24, 1998 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-9506524

RESUMEN

The ABO(H) histoblood group genes have been mapped by linkage analysis to 9q34.1-34.2, an area of common deletions in bladder cancer. Lack of ABO(H) antigen expression in bladder tumors is a frequent and well-documented event. In bladder neoplasms the loss of A and B transferase activity is due to down-regulation of the ABO gene transcripts. Our study was undertaken in order to determine the presence of structural alterations of the ABO(H) gene-encoding locus in primary bladder tumors, to estimate the extent of allelic deletions and to characterize further the pattern of histoblood group antigen expression. Fifty-three primary bladder tumors were analyzed by immuno-histochemistry (IHC) using a panel of well-characterized antibodies and fresh frozen tissue sections. Normal and tumor DNA also were analyzed by PCR coupled with restriction enzyme analysis in order to establish the ABO genotype. Results obtained from these analyses were then compared to allelotyping data at the 9q34.1-4 region by Southern blotting. IHC data showed undetectable levels of antigen expression on neoplastic cells in 59% of informative cases. PCR-based genotypic results revealed allelic losses in 27% of heterozygous cases. Four of the 16 pheno- and/or genotypically altered cases (25%) presented loss of heterozygosity at D9S10 or D9S7 loci. Our data indicate that the lack of ABO antigen expression in certain bladder tumors is due to the allelic loss of the ABO glycosyltransferase-encoding genes and that in some of these tumors the loss involves the surrounding chromosomal region at 9q34.1-4.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/genética , Antígenos de Neoplasias/genética , Neoplasias de la Vejiga Urinaria/inmunología , Cromosomas Humanos Par 9 , ADN de Neoplasias/genética , Regulación Neoplásica de la Expresión Génica , Genotipo , Humanos , Pérdida de Heterocigocidad , Fenotipo , Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/genética
16.
Proc Natl Acad Sci U S A ; 92(18): 8488-92, 1995 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-7667316

RESUMEN

The positive effects of Myc on cellular growth and gene expression are antagonized by activities of another member of the Myc superfamily, Mad. Characterization of the mouse homolog of human mad on the structural level revealed that domains shown previously to be required in the human protein for anti-Myc repression, sequence-specific DNA-binding activity, and dimerization with its partner Max are highly conserved. Conservation is also evident on the biological level in that both human and mouse mad can antagonize the ability of c-myc to cooperate with ras in the malignant transformation of cultured cells. An analysis of c-myc and mad gene expression in the developing mouse showed contrasting patterns with respect to tissue distribution and developmental stage. Regional differences in expression were more striking on the cellular level, particularly in the mouse and human gastrointestinal system, wherein c-Myc protein was readily detected in immature proliferating cells at the base of the colonic crypts, while Mad protein distribution was restricted to the postmitotic differentiated cells in the apex of the crypts. An increasing gradient of Mad was also evident in the more differentiated subcorneal layers of the stratified squamous epithelium of the skin. Together, these observations support the view that both downregulation of Myc and accumulation of Mad may be necessary for progression of precursor cells to a growth-arrested, terminally differentiated state.


Asunto(s)
Diferenciación Celular/fisiología , División Celular/fisiología , Proteínas de Unión al ADN/fisiología , Proteínas Proto-Oncogénicas c-myc/fisiología , Proteínas Represoras , Animales , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Transformación Celular Neoplásica , Proteínas de Unión al ADN/genética , Humanos , Mucosa Intestinal/metabolismo , Ratones , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-myc/genética , Ratas , Piel/metabolismo , Especificidad de la Especie
17.
Am J Pathol ; 153(1): 183-90, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9665479

RESUMEN

The repertoire of distinct CD44 protein isoforms is generated by means of alternative pre-mRNA splicing of 10 variable exons located in the central region of the CD44 gene. We have used human breast ductal carcinoma as a model to identify two alternative splicing pathways of the CD44 pre-mRNA variable region that account for the generation of all of the CD44 isoforms described in breast tissue. An alternative splicing pathway that reflects inclusion of variable exons in a gradual 3'-to-5' fashion is evidenced in breast ductal carcinoma and its lymph node metastases. This pathway is compatible with a mechanism that generates the standard form of CD44 (devoid of variable exons) and is distinguishable from an alternative splicing pathway that involves exclusively variant exon 3 and is observable in both normal and carcinoma breast tissue. We show that both pathways are detectable in the same cell type in the breast and provide a speculative model by which these splicing routes could take place.


Asunto(s)
Empalme Alternativo , Neoplasias de la Mama/inmunología , Mama/inmunología , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Clonación Molecular , Femenino , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Técnicas para Inmunoenzimas , Reacción en Cadena de la Polimerasa , Transcripción Genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA