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1.
Ann Oncol ; 17(4): 563-70, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16418308

RESUMEN

BACKGROUND: This randomized phase III trial was designed to demonstrate the superiority of autologous peptide-loaded dendritic cell (DC) vaccination over standard dacarbazine (DTIC) chemotherapy in stage IV melanoma patients. PATIENTS AND METHODS: DTIC 850 mg/m2 intravenously was applied in 4-week intervals. DC vaccines loaded with MHC class I and II-restricted peptides were applied subcutaneously at 2-week intervals for the first five vaccinations and every 4 weeks thereafter. The primary study end point was objective response (OR); secondary end points were toxicity, overall (OS) and progression-free survival (PFS). RESULTS: At the time of the first interim analysis 55 patients had been enrolled into the DTIC and 53 into the DC-arm (ITT). OR was low (DTIC: 5.5%, DC: 3.8%), but not significantly different in the two arms. The Data Safety & Monitoring Board recommended closure of the study. Unscheduled subset analyses revealed that patients with normal serum LDH and/or stage M1a/b survived longer in both arms than those with elevated serum LDH and/or stage M1c. Only in the DC-arm did those patients with (i) an initial unimpaired general health status (Karnofsky = 100) or (ii) an HLA-A2+/HLA-B44- haplotype survive significantly longer than patients with a Karnofsky index <100 (P = 0.007 versus P = 0.057 in the DTIC-arm) or other HLA haplotypes (P = 0.04 versus P = 0.57 in DTIC-treated patients). CONCLUSIONS: DC vaccination could not be demonstrated to be more effective than DTIC chemotherapy in stage IV melanoma patients. The observed association of overall performance status and HLA haplotype with overall survival for patients treated by DC vaccination should be tested in future trials employing DC vaccines.


Asunto(s)
Vacunas contra el Cáncer/administración & dosificación , Dacarbazina/uso terapéutico , Células Dendríticas/trasplante , Melanoma/terapia , Péptidos/administración & dosificación , Humanos , Melanoma/patología , Metástasis de la Neoplasia
2.
Cancer Lett ; 242(1): 104-11, 2006 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-16338063

RESUMEN

The glucocorticoid dexamethasone is frequently used as co-treatment in cytotoxic cancer therapy, e.g. to prevent nausea, to protect normal tissue or for other reasons. While the potent pro-apoptotic properties and the supportive effects of glucocorticoids to tumour therapy in lymphoid cells are well studied, the impact to cytotoxic treatment of colorectal and hepatocellular carcinoma is unknown. We tested apoptosis-induction, viability, tumour growth and protein expression using 8 established cell lines, 18 surgical specimen and a xenograft on nude mice. In the presence of dexamethasone we found strong inhibition of apoptosis in response to 5-FU, cisplatin, gemcitabine or gamma-irradiation, enhanced viability and tumour growth of colorectal and hepatocellular carcinomas. No correlation with age, gender, histology, TNM, the p53 status and induction of therapy resistance by dexamethasone co-treatment could be detected. These data show that glucocorticoid-induced resistance occurs not occasionally but is common in colorectal and hepatocellular carcinomas implicating that the use of glucocorticoids may be harmful for cancer patients.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Dexametasona/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Animales , Antiinflamatorios no Esteroideos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Línea Celular Tumoral , Femenino , Glucocorticoides/metabolismo , Humanos , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Trasplante de Neoplasias
3.
Cancer Biol Ther ; 5(1): 59-64, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16294015

RESUMEN

PURPOSE: Glucocorticoids such as dexamethasone are widely used for medication of urological diseases, e.g., as cotreatment of advanced prostate cancer, to improve appetite, weight loss, fatigue, relieve bone pain, diminish ureteric obstruction, to reduce the production of adrenal androgens, as an antiemetic in patients undergoing chemo- and/or radiotherapy together with serving as "standard" therapy arm in randomized studies. While the potent pro-apoptotic properties and the supportive effects of glucocorticoids to tumor therapy in lymphoid cells are well studied, the impact to growth of prostate and other urological carcinomas is unknown. METHODS: We isolated cells from surgical resections of 21 prostate tumors and measured apoptosis and viability in these primary cells and 17 established cell lines from human prostate, bladder, renal cell and testicular carcinomas. RESULTS: We found that dexamethasone induces resistance regarding exposure to several cytotoxic agents such as taxol, gemcitabine, cisplatin, 5-FU and gamma-irradiation in 86% of the freshly isolated prostate tumors and in 100% of the established urological cell lines. No difference in dexamethasone-mediated protection was found in normal, benign and malignant prostate tumors. CONCLUSIONS: These data show for the first time that dexamethasone induced therapy resistance in urological carcinomas is not the exception but a more common phenomenon and implicate that glucocorticoids may have two faces in cancer therapy, a beneficial and a dangerous one.


Asunto(s)
Corticoesteroides/efectos adversos , Dexametasona/efectos adversos , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Urológicas/terapia , Apoptosis , Femenino , Humanos , Masculino , Tolerancia a Radiación/efectos de los fármacos , Neoplasias Urológicas/tratamiento farmacológico , Neoplasias Urológicas/radioterapia
4.
Br J Cancer ; 92(8): 1398-405, 2005 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-15846297

RESUMEN

This two-centre phase-II trial aimed at investigating the efficacy of imatinib in metastasised melanoma patients in correlation to the tumour expression profile of the imatinib targets c-kit and platelet-derived growth factor receptor (PDGF-R). The primary study end point was objective response according to RECIST, secondary end points were safety, overall and progression-free survival. In all, 18 patients with treatment-refractory advanced melanoma received imatinib 800 mg day(-1). In 16 evaluable patients no objective responses could be observed. The median overall survival was 3.9 months, the median time to progression was 1.9 months. Tumour biopsy specimens were obtained from 12 patients prior to imatinib therapy and analysed for c-kit, PDGF-Ralpha and -Rbeta expression by immunohistochemistry. In four cases, cell lines established from these tumour specimens were tested for the antiproliferative effects of imatinib and for functional mutations of genes encoding the imatinib target molecules. The tumour specimens stained positive for CD117/c-kit in nine out of 12 cases (75%), for PDGF-Ralpha in seven out of 12 cases (58%) and for PDGF-Rbeta in eight out of 12 cases (67%). The melanoma cell lines showed a heterogenous expression of the imatinib target molecules without functional mutations in the corresponding amino-acid sequences. In vitro imatinib treatment of the cell lines showed no antiproliferative effect. In conclusion, this study did not reveal an efficacy of imatinib in advanced metastatic melanoma, regardless of the expression pattern of the imatinib target molecules c-kit and PDGF-R.


Asunto(s)
Antineoplásicos/uso terapéutico , Melanoma/tratamiento farmacológico , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Adulto , Anciano , Secuencia de Bases , Benzamidas , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Análisis Mutacional de ADN , Femenino , Humanos , Mesilato de Imatinib , Inmunohistoquímica , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Datos de Secuencia Molecular , Metástasis de la Neoplasia/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-kit/efectos de los fármacos , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Receptores del Factor de Crecimiento Derivado de Plaquetas/efectos de los fármacos , Receptores del Factor de Crecimiento Derivado de Plaquetas/genética , Receptores del Factor de Crecimiento Derivado de Plaquetas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Resultado del Tratamiento
5.
Leukemia ; 16(10): 2096-105, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12357363

RESUMEN

Bendamustine is a novel cytostatic agent, with activity in non-Hodgkin's lymphomas including B-chronic lymphocytic leukemia (B-CLL). The knowledge about its mode of action, however, is still limited. Here, we investigated the in vitro ability of bendamustine to induce apoptosis on freshly isolated peripheral lymphocytes in B-CLL and analyze the potential underlying mechanisms of action for inducing apoptosis. In CLL cells taken from 37 previously treated and untreated CLL patients, we investigated the influence of bendamustine alone, and in combination with fludarabine, on the induction of apoptosis and changes of Bcl-2 and Bax expression on mRNA and protein level using the RNase protection assay or flow cytometry, respectively. Apoptotic cells were determined with flow cytometry using the fluorescent DNA-binding agent 7-ADD. Using bendamustine alone in concentrations from 1 microg/ml to 50 microg/ml, a dose- and time-dependent manner of cytotoxicity from 30.4% to 94.8% after 48 h could be observed. The LD50 for untreated and pretreated CLL cells was 7.3 or 4.4 microg/ml, respectively. The median apoptotic rate was similar in both groups. The combination of bendamustine with fludarabine led to a highly synergistic effect in inducing apoptosis, which was 150% higher than expected for bendamustine plus fludarabine. The level of the initial Bcl-2 and Bax protein and the m-RNA expression remained unchanged during the incubation with bendamustine. In conclusion, this study demonstrates for the first time the in vitro efficacy of bendamustine in inducing apoptosis in B-CLL cells alone and in combination with fludarabine.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Compuestos de Mostaza Nitrogenada/farmacología , Proteínas Proto-Oncogénicas c-bcl-2 , Antineoplásicos/uso terapéutico , Clorhidrato de Bendamustina , Western Blotting , Citometría de Flujo , Técnicas In Vitro , Leucemia Linfocítica Crónica de Células B/enzimología , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Monocitos/efectos de los fármacos , Compuestos de Mostaza Nitrogenada/uso terapéutico , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteína X Asociada a bcl-2
6.
Br J Cancer ; 87(2): 151-7, 2002 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-12107834

RESUMEN

In a German cohort of 661 melanoma patients the performance, costs and survival benefits of staging methods (history and physical examination; chest X-ray; ultrasonography of the abdomen; high resolution sonography of the peripheral lymph nodes) were assessed at initial staging and during follow-up of stage I/II+III disease. At initial staging, 74% (23 out of 31) of synchronous metastases were first detected by physical examination followed by sonography of the lymph nodes revealing 16% (5 out of 31). Other imaging methods were less efficient (Chest X-ray: one out of 31; sonography of abdomen: two out of 31). Nearly 24% of all 127 first recurrences and 18% of 73 second recurrences developed in patients not participating in the follow-up programme. In follow-up patients detection of first or second recurrence were attributed to history and physical examination on a routine visit in 47 and 52% recurrences, respectively, and to routine imaging procedures in 21 and 17% of cases, respectively. Lymph node sonography was the most successful technical staging procedure indicating 13% of first relapses, but comprised 24% of total costs of follow-up in stage I/II. Routine imaging comprised nearly 50% of total costs for follow-up in stage I/II and in stage III. The mode of detecting a relapse ('patient vs. doctor-diagnosed' or 'symptomatic vs asymptomatic') did not significantly influence patients overall survival. Taken together, imaging procedures for routine follow-up in stage I/II and stage III melanoma patients were inefficient and not cost-efficient.


Asunto(s)
Melanoma/patología , Estadificación de Neoplasias/métodos , Neoplasias Abdominales/diagnóstico por imagen , Neoplasias Abdominales/secundario , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Estudios de Cohortes , Análisis Costo-Beneficio , Pruebas Diagnósticas de Rutina/economía , Femenino , Alemania/epidemiología , Costos de la Atención en Salud , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/secundario , Metástasis Linfática/diagnóstico por imagen , Masculino , Melanoma/diagnóstico por imagen , Melanoma/economía , Melanoma/mortalidad , Melanoma/secundario , Melanoma/terapia , Recurrencia Local de Neoplasia , Estadificación de Neoplasias/economía , Examen Físico , Radiografía Torácica/economía , Cintigrafía/economía , Estudios Retrospectivos , Análisis de Supervivencia , Tomografía Computarizada por Rayos X/economía , Ultrasonografía/economía
8.
Int J Cancer ; 92(1): 1-8, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11279599

RESUMEN

RT-PCR-based amplification of transcripts expressed in cancer but not in normal non-neoplastic cells is increasingly used for the sensitive detection of rare disseminated or exfoliated cancer cells to improve cancer staging and early detection protocols. However, these assays are frequently hampered by false-positive test results due to low-level transcription of the marker genes in normal cells. To overcome these limitations, target transcripts have to be identified that are tightly suppressed in normal non-neoplastic tissues, whereas they should be actively transcribed in the respective cancer cells. Here, we tested RT-PCR assays for 7 neuroendocrine marker transcripts including NCAM, PGP 9.5, gastrin, gastrin receptor, synaptophysin, preprogastrin-releasing peptide (preproGRP) and GRP-receptor to detect rare exfoliated tumor cells in peripheral venous blood and sputum samples from patients with lung cancer. Among these preproGRP RT-PCR was the only assay with which illegitimate transcription in blood or sputum samples from healthy donors or patients with unrelated diseases did not interfere. However, it reproducibly detected up to 10 small-cell lung cancer cells diluted in either 10 ml blood or 5 ml sputum samples. Single blood and sputum samples were collected directly before diagnostic bronchoscopy from 175 patients suspected to have lung cancer. Twenty-six of these had small-cell lung cancer (SCLC). Thereof, 13 patients (50%) tested positive in the blood sample and 5 of 23 patients (22%) tested positive in the sputum sample. Moreover, among 92 patients with non-small-cell lung cancer (NSCLC) 25 patients (27%) had disseminated cancer cells in peripheral blood. Amplification of preproGRP transcripts from clinical samples is a sensitive and specific assay to detect disseminated or exfoliated lung cancer cells either in peripheral blood or sputum samples.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Pulmonares/patología , Células Neoplásicas Circulantes/química , Péptidos/genética , Precursores de Proteínas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esputo/citología , Carcinoma de Pulmón de Células no Pequeñas/química , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Pequeñas/química , Carcinoma de Células Pequeñas/patología , Humanos , Leucocitos Mononucleares/química , Neoplasias Pulmonares/química , Estadificación de Neoplasias , ARN Mensajero/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Células Tumorales Cultivadas
9.
Int J Cancer ; 95(2): 86-91, 2001 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-11241317

RESUMEN

DNA repair capacity in human peripheral blood lymphocytes was monitored by the repair rate of bleomycin-induced DNA damage using an alkaline single-cell gel electrophoresis assay (comet assay). DNA repair capacity, after 15 min repair time, in lymphocytes of non-small cell lung cancer patients (n = 160) and controls (n = 180) was 67% and 79.3%, respectively (p < 0.0004). Bleomycin sensitivity defined as the tail moment of bleomycin-treated peripheral blood lymphocytes, without allowing time for DNA repair, was significantly higher in lung cancer patients than in tumor-free hospital controls (p < 0.0001). There was no correlation, in either patient or control group, between the bleomycin sensitivity and DNA repair capacity with age or gender. The median values of DNA repair capacity and sensitivity in controls were used as the cut-off points for calculating odds ratios (OR). After adjustment for age, gender and smoking status, the cases vs. controls had reduced DNA repair capacity (OR = 2.1; 95% confidence limit [CL] 1.1-4.0) and increased bleomycin sensitivity (OR = 4; 95% CL 2.2-7.4). For current smokers, the adjusted risk associated with bleomycin sensitivity was 2.3 (95% CL 1.1-4.9). We conclude that our standard comet assay as a phenotypical repair test has sufficient sensitivity and rapidity allowing application to both native and cryopreserved lymphocytes. Bleomycin sensitivity and DNA repair capacity were found to be 2 independent susceptibility markers for non-small cell lung cancer, confirming similar investigations with different marker end points. The latter were much more time consuming than the method used in our study. Thus, the comet assay is more suitable for screening large numbers of individuals in epidemiological studies. Validation of this assay in large prospective studies for the identification of subjects at high risk for non-small cell lung cancer is now warranted.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Reparación del ADN , Resistencia a Antineoplásicos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Factores de Edad , Anciano , Carcinoma de Pulmón de Células no Pequeñas/sangre , Estudios de Casos y Controles , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Neoplasias Pulmonares/sangre , Linfocitos/metabolismo , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Factores de Riesgo , Factores Sexuales , Fumar , Factores de Tiempo
10.
Mutagenesis ; 16(1): 25-30, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11139596

RESUMEN

Individual susceptibility to carcinogens, an important determinant of disease risk, is influenced by host factors such as the ability to repair DNA lesions. In order to identify subjects who are at high risk, we have developed a microgel electrophoresis assay for use in molecular epidemiological studies. The assay was validated in a pilot case-control study: Peripheral blood lymphocytes were collected from 100 patients with lung cancer and 110 control patients without cancer and from the same hospital, and stored at -80 degrees C. After thawing, phytohaemagglutinin-stimulated cells were treated with bleomycin at 20 microg/ml for 30 min and the extent of DNA damage and DNA repair capacity were determined by microgel electrophoresis. Peripheral blood lymphocytes from patients with lung cancer were significantly more sensitive to mutagens than those from controls and showed reduced DNA repair capacity (both P < 0.001). Both endpoints were independent risk factors for smoking-related lung cancer. Repeated analysis of peripheral blood lymphocytes from the same individual demonstrated good reproducibility of the assay. Cryopreservation of the lymphocytes for less than or = 12 months did not significantly affect their sensitivity. Our standardized microgel electrophoresis assay is suitable for determining individual sensitivity to mutagens and DNA repair capacity: it is sensitive and faster than cytogenetic assays, and can be applied to native and cryopreserved peripheral blood lymphocytes.


Asunto(s)
Reparación del ADN , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Adulto , Antimetabolitos Antineoplásicos/toxicidad , Bleomicina/toxicidad , Estudios de Casos y Controles , Células Cultivadas , Daño del ADN/efectos de los fármacos , Daño del ADN/genética , Reparación del ADN/efectos de los fármacos , Electroforesis en Gel de Agar/métodos , Femenino , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad , Proyectos Piloto
11.
J Epidemiol Biostat ; 6(6): 425-32, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11831678

RESUMEN

BACKGROUND: European guidelines for breast-cancer screening recommend an integrated approach of mammography screening with subsequent assessment and biopsy, if required, in one screening unit under permanent quality control, for which target values are released. Although the calculation of the respective rates (e.g. for participation, assessment, biopsy, or cancer detection) appears trivial, the statistical assessment of their compatibility with the target values is less obvious. This is especially true if subjects with a positive diagnostic result leave the screening-assessment chain prematurely, and information about further diagnostic results outside the organised screening is lacking. METHOD: Statistical models for the basic situation, in which complete information about the screening and assessment outcome is available, as well as for when information is incomplete, are presented. The statistical methods for obtaining the confidence limits, statistical tests and sample sizes needed to obtain a desired power of tests for the process parameters of interest are also given. RESULTS: The sample-size calculations indicate that large numbers of enrolled subjects are required to obtain reasonably narrow confidence limits, and that incomplete information about the outcome of diagnostic procedures among screening positives considerably worsens the feasibility of quality control. CONCLUSIONS: Although the methodology is specified for breast-cancer screening, it should be adaptable easily to other screening issues.


Asunto(s)
Neoplasias de la Mama/epidemiología , Mamografía/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Mamografía/instrumentación , Modelos Estadísticos , Control de Calidad
12.
Anticancer Res ; 20(5B): 3449-58, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11131647

RESUMEN

The main objective of this study to analyze which of 31 cellular factors (resistance proteins, proliferative factors, apoptotic factors, angiogenic factors, proto-oncogenes) most accurately predict the resistance of non-small cell lung carcinomas. To this purpose, we used a short-term in vitro test that measures changes in the rate at which radioactive nucleic acid precursors are incorporated into tumor cells after the addition of doxorubicin to determine the response to doxorubicin in 94 non-small cell lung carcinomas. The results obtained by the short-term test were related to the various cellular factors which were in turn determined by immunohistochemistry and flow cytometry. A significant correlation was found between the data obtained by the short-term test and the expression of P-glycoprotein 170 (P = 0.00004), glutathione-S-transferase-pi (P = 0.0002), metallothionein (P = 0.0008), thymidylate synthase (P = 0.002), O6-methylguanine-DNA-methyltransferase (P = 0.008) and lung resistance-related protein (LRP, P = 0.03). There was only a weak correlation between heat shock proteins (HSP70) and no correlation between the expression of topoisomerase II or catalase and the short-term test results. To measure the proliferative activity, the following were determined: PCNA, cyclin A, cyclin D and cdk2. Only a weak relationship was found between the expression of cdk2 (P = 0.04) and PCNA (P = 0.05) and the doxorubicin response in vitro. Of the investigated pro-apoptotic factors (Fas/CD95, Fas ligand, caspase-3), only Fas/CD95 is significantly associated with the drug response (P = 0.007). The apoptotic index also reveals a significant correlation (P = 0.03). Angiogenesis, as measured by the microvessel density and the angiogenic factors, is inversely correlated to the resistance of non-small cell lung cancer. Platelet-derived endothelial cell growth factor (PD-ECGF) and vascular endothelial growth factor (VEGF) exhibit a significant relationship to the drug resistance (P = 0.0006 and P = 0.004, respectively). Of the investigated proto-oncogenes (Fos, Jun, ErbB-1, ErbB-2, Myc, Ras), only ErbB-2 is weakly associated with the in vitro short term test. In order to determine whether combining factors can result in improved predictive information, combinations of the factors (pairs, triplets) were analyzed. The systematic investigation of these combinations yields an improvement in the predictive information. With one factor up to 76.6% of the tumors, with two factors up to 85.4% and with three factors up to 89.5% of the tumors could be correctly diagnosed.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Resistencia a Antineoplásicos/fisiología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Antibióticos Antineoplásicos/farmacología , Apoptosis/fisiología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , División Celular/fisiología , Doxorrubicina/farmacología , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/biosíntesis , Valor Predictivo de las Pruebas , Proto-Oncogenes
13.
Biometrics ; 56(4): 1164-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11129474

RESUMEN

The evaluation of epidemiological follow-up studies is frequently based on a comparison of the number O of deaths observed in the cohort from a specified cause with the expected number E calculated from person years in the cohort and mortality rates from a reference population. The ratio SMR = 100 x O/E is called the standardized mortality ratio (SMR). While person years can easily be calculated from the cohort and reference rates are generally available from the national statistical offices or the World Health Organization (WHO), problems can arise with the accessibility of the causes of death of the deceased study participants. However, the information that a person has died may be available, e.g., from population registers. In this paper, a statistical model for this situation is developed to derive a maximum likelihood (ML) estimator for the true (but unknown) number O* of deaths from a specified cause, which uses the known number O of deaths from this cause and the proportion p of all known causes of death among all decreased participants. It is shown that the standardized mortality ratio SMR* based on this estimated number is just SMR* = SMR/p. Easily computable confidence limits can be obtained by dividing the usual confidence limits of the SMR by the opposite limit of the proportion p. However, the confidence level alpha has to be adjusted appropriately.


Asunto(s)
Biometría/métodos , Causas de Muerte , Certificado de Defunción , Estudios de Seguimiento , Modelos Estadísticos , Tasa de Supervivencia , Estudios de Cohortes , Intervalos de Confianza , Humanos , Funciones de Verosimilitud , Neoplasias/clasificación , Neoplasias/mortalidad , Distribución de Poisson , Valores de Referencia , Enfermedades Respiratorias/mortalidad
14.
Anticancer Res ; 20(3B): 2203-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10928178

RESUMEN

BACKGROUND: Detection of S100 beta in serum has been shown to be a significant prognostic marker for malignant melanoma in earlier studies. Melanoma inhibiting activity (MIA) has recently been detected as a new serum marker for malignant melanoma. MATERIALS AND METHODS: In the present study, serum levels of S100 beta protein and MIA were measured over a time period of up to 18 months in 271 serum samples from 65 melanoma patients at different stages of disease, during chemotherapy and/or immunotherapy. In addition, 46 sera of control patients were analysed. The aim of this study was to compare both potential markers. S100 beta was measured using the immunoluminometric assay LIA-mat Sangtec (Byk Sangtec Diagnostica) with a cut-off level of 0.12 microgram/l. MIA was determined by the MIA ELISA kit (Roche) using a cut-off level of 6.5 ng/ml. RESULTS: In 53 patients a direct correlation of S-100 values and clinical course could be observed (81.5%), whereas in 48 patients MIA-values and clinical course (73.8%) showed an association. S100 beta levels were incorrectly elevated in 5 out of 25 sera, "false positive" (20%)) and were in 8 out of 40 sera not elevated despite the detection of metastases "false negative" (20%)). Assessing the MIA levels, 2 out of 25 probes were false positive (8%) and 13 out of 40 probes false negative(32.5%). CONCLUSION: Our data strongly suggest that S100 and MIA represent serum tumor markers that are valuable both in therapy-monitoring and in detection of tumour progression.


Asunto(s)
Biomarcadores de Tumor/sangre , Melanoma/sangre , Proteínas de Neoplasias/sangre , Proteínas S100/sangre , Neoplasias Cutáneas/sangre , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cisplatino/administración & dosificación , Terapia Combinada , Dacarbazina/administración & dosificación , Progresión de la Enfermedad , Proteínas de la Matriz Extracelular , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Estudios de Seguimiento , Humanos , Factores Inmunológicos/uso terapéutico , Interferón-alfa/uso terapéutico , Interleucina-2/uso terapéutico , Masculino , Melanoma/tratamiento farmacológico , Melanoma/patología , Melanoma/terapia , Metástasis de la Neoplasia , Estadificación de Neoplasias , Sensibilidad y Especificidad , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/terapia , Resultado del Tratamiento , Neoplasias de la Úvea/sangre , Neoplasias de la Úvea/tratamiento farmacológico , Neoplasias de la Úvea/patología , Neoplasias de la Úvea/terapia
15.
Int J Cancer ; 79(3): 294-9, 1998 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-9645354

RESUMEN

In the search for new risk factors at the molecular and cellular levels, clinical data [lymph-node involvement(LN)and stage] were used and 104 squamous-cell lung carcinomas were analyzed by immuno-histochemistry for expression of cyclin D1, cyclin A, cdk2, cdk4, RB, and E2F1. The results of the univariate analysis of all 8 factors showed that cyclin A and cdk2 gave the best prognostic information, while no prognostic value could be found associated with cyclin D1, cdk4, RB and E2F1. The subsequent multivariate analysis of all possible combinations of the important factors showed that the pairs LN/cyclin A, LN/cdk2 and cyclin A/cdk2, and the triplet LN/cyclin A/cdk2 yielded the best prognostic information. It was essentially better than the information given by a single factor.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Proteínas Portadoras , Proteínas de Ciclo Celular , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Proteínas de Unión al ADN , Neoplasias Pulmonares/metabolismo , Proteína de Retinoblastoma/metabolismo , Factores de Transcripción/metabolismo , Carcinoma de Células Escamosas/mortalidad , Ciclina A/metabolismo , Ciclina D , Factores de Transcripción E2F , Factor de Transcripción E2F1 , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico , Proteína 1 de Unión a Retinoblastoma , Factores de Tiempo , Factor de Transcripción DP1
16.
Br J Cancer ; 77(4): 663-9, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9484827

RESUMEN

Patients with previously untreated squamous cell lung carcinomas were evaluated to see if combining the expression of molecular and cellular factors with the most important clinical prognostic factors could improve the diagnostic ability to predict prognosis. For this reason, immunohistochemistry was used to examine the squamous cell lung carcinomas from 121 patients for their expression of ERBB-1, vascular endothelial growth factor (VEGF), cyclin A, FOS, JUN and MYC. Median survival was shorter for patients with ERBB-1-, VEGF-, cyclin A-, FOS-, or JUN-positive tumours. For those patients with positive lymph node involvement, the survival times were also shorter in the VEGF-positive, cyclin A-positive and FOS-positive groups. Multivariate analysis independently demonstrated a significant prognostic value for lymph node involvement, VEGF and FOS.


Asunto(s)
Carcinoma de Células Escamosas/química , Neoplasias Pulmonares/química , Proteínas de Neoplasias/análisis , Adulto , Anciano , Carcinoma de Células Escamosas/mortalidad , Ciclina A/análisis , Factores de Crecimiento Endotelial/análisis , Receptores ErbB/análisis , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Linfocinas/análisis , Masculino , Persona de Mediana Edad , Pronóstico , Proteínas Proto-Oncogénicas c-fos/análisis , Proteínas Proto-Oncogénicas c-jun/análisis , Proteínas Proto-Oncogénicas c-myc/análisis , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
Int J Cancer ; 74(5): 508-12, 1997 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-9355972

RESUMEN

Immunohistochemistry was used to analyze samples of 40 newly diagnosed childhood acute lymphoblastic leukemias (ALL) for their expression of cyclins (D1, E, A), cyclin-dependent kinases (cdk2, cdk4) and tumor-suppressor genes (pRb, p16INK4A), in order to discover whether or not the expression of these various proteins may be of prognostic relevance for the survival of children with ALL. Patients with ALL who were strongly positive for cyclin D1 had a lower probability of remaining in first continuous remission than ALL patients who were negative or weakly positive for this trait. There was also a significant correlation between expression of cyclin D1 and frequency of recurrence. For cyclin E and cyclin A, in contrast, there was no difference in the duration of relapse-free-intervals or the frequency of recurrence in patients. Children with cdk4-positive ALL had a lower probability of remaining in first continuous remission than children with cdk4-negative ALL. No prognostic relevance was found for cdk2. Patients with ALL who expressed pRb had a higher probability and patients who expressed p16 a lower probability of remaining in first continuous remission, but the results were not statistically significant. This investigation demonstrated that cyclin D1 and cdk4 were the most important prognostic factors for children with ALL, and that the combination of them showed the strongest prognostic relevance.


Asunto(s)
Quinasas CDC2-CDC28 , Quinasas Ciclina-Dependientes/análisis , Ciclinas/análisis , Genes de Retinoblastoma , Genes p16 , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Serina-Treonina Quinasas/análisis , Proteínas Proto-Oncogénicas , Adolescente , Niño , Preescolar , Quinasa 2 Dependiente de la Ciclina , Quinasa 4 Dependiente de la Ciclina , Femenino , Humanos , Inmunohistoquímica , Lactante , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimología , Pronóstico
18.
Math Biosci ; 120(2): 147-63, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8204982

RESUMEN

The use of an extended version of the cumulative damage model to identify and quantify cancer risk arising from a specified exposure is outlined. For this, a strategy to fit the model to individual data coming from epidemiologic follow-up studies is described. Two statistical problems are addressed: first, the regularity of the model has to be ascertained to allow the application of maximum-likelihood and likelihood-ratio methods for parameter estimation and testing. Second, a statistical test has to be found that permits testing goodness of fit in the setting of parameter estimation with individual data. As an example, these methods are applied to the data of a cohort study on mortality among stainless steel welders in the Federal Republic of Germany. The results show that the model fits the data well and confirms a carcinogenic effect of stainless steel welding among welders. Some distinguishing characteristics of the model, especially its prediction of a potentially decreasing relative risk despite ongoing carcinogenic exposure, are discussed.


Asunto(s)
Métodos Epidemiológicos , Modelos Biológicos , Carcinógenos/toxicidad , Estudios de Seguimiento , Humanos , Funciones de Verosimilitud , Matemática , Neoplasias/epidemiología , Neoplasias/etiología , Riesgo
19.
Math Biosci ; 108(1): 57-73, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1550997

RESUMEN

Cumulative damage models conceive the epidemiologically observed aspects of carcinogenesis as some kind of total balance over a complex biological process and suggest that this total balance might behave as a wear-and-tear process. The essential concepts of this mechanistic model are exposure to a carcinogenically damaging environment and resistance of a host system against those damages. Intensity of exposure and magnitude of host resistance are the parameters to be assessed. The paper describes (1) the statistical methods for fitting this model to birth cohort data; (2) for which cancer sites the model provides acceptable fits and for which it does not; and (3) how model extensions provide improvements in the goodness of fit. It is shown that from a theoretical viewpoint the consideration of extra-Poisson variation is needed for descriptive epidemiological applications. The practical examples indicate that the present version of the model provides acceptable fits for only a few cancer sites and that refinements are needed in the majority of sites. However, plausible model extensions suggest considerable improvements of goodness of fit.


Asunto(s)
Neoplasias Pulmonares/mortalidad , Modelos Biológicos , Neoplasias Gástricas/mortalidad , Carcinógenos , Exposición a Riesgos Ambientales , Femenino , Humanos , Neoplasias Pulmonares/etiología , Masculino , Matemática , Neoplasias Gástricas/etiología
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