RESUMEN
Circulating tumor cells (CTC) have been studied in various solid tumors but clinical utility of CTC in small cell lung cancer (SCLC) remains unclear. The aim of the CTC-CPC study was to develop an EpCAM-independent CTC isolation method allowing isolation of a broader range of living CTC from SCLC and decipher their genomic and biological characteristics. CTC-CPC is a monocentric prospective non-interventional study including treatment-naïve newly diagnosed SCLC. CD56+ CTC were isolated from whole blood samples, at diagnosis and relapse after first-line treatment and submitted to whole-exome-sequencing (WES). Phenotypic study confirms tumor lineage and tumorigenic properties of isolated cells for the 4 patients analyzed with WES. WES of CD56+ CTC and matched tumor biopsy reveal genomic alteration frequently impaired in SCLC. At diagnosis CD56+ CTC were characterized by a high mutation load, a distinct mutational profile and a unique genomic signature, compared to match tumors biopsies. In addition to classical pathways altered in SCLC, we found new biological processes specifically affected in CD56+ CTC at diagnosis. High numeration of CD56+ CTC (> 7/ml) at diagnosis was associated with ES-SCLC. Comparing CD56+ CTC isolated at diagnosis and relapse, we identify differentially altered oncogenic pathways (e.g. DLL3 or MAPK pathway). We report a versatile method of CD56+ CTC detection in SCLC. Numeration of CD56+ CTC at diagnosis is correlated with disease extension. Isolated CD56+ CTC are tumorigenic and show a distinct mutational profile. We report a minimal gene set as a unique signature of CD56+ CTC and identify new affected biological pathways enriched in EpCAM-independent isolated CTC in SCLC.
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Neoplasias Pulmonares , Células Neoplásicas Circulantes , Carcinoma Pulmonar de Células Pequeñas , Humanos , Molécula de Adhesión Celular Epitelial , Relevancia Clínica , Estudios Prospectivos , Genómica , Carcinogénesis , Proteínas de la Membrana , Péptidos y Proteínas de Señalización IntracelularRESUMEN
In cases of advanced EGFR mutation-positive non-small cell lung cancer, first or second generation EGFR-tyrosine kinase inhibitors (TKI-EGFR 1G or TKI-EGFR 2G) are recommended as first line treatment. Inexorably, progressive disease occurs and, in 50-60% of the cases, is secondary to a T790M resistant mutation. The prescription of osimertinib (TKI-EGFR3G) in second line is dependent on identification of the T790M mutation. We report 7 cases in which the identification of the T790M mutation required repeated analyses of cell free DNA and/or biopsies over a period of time. In some cases, a positive result was obtained a long time after progressive disease had been diagnosed during treatment with first or second generation EGFR-TKI. We discuss here the different modalities of screening for the T790M mutation and we encourage persevering in this search when no alternative mechanism of resistance has been identified.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Análisis Mutacional de ADN , Resistencia a Antineoplásicos/genética , Neoplasias Pulmonares/genética , Mutación Missense , Anciano , Sustitución de Aminoácidos , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/genética , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Metionina/genética , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Treonina/genética , Factores de TiempoRESUMEN
Nocardiosis is an infectious disease with wide range of clinical features, which can eventually lead to death. The agent responsible belongs to the genus Nocardia that includes about fifty different species. Nocardiosis occurs mainly in immunocompromised hosts. We report here three cases of disseminated nocardiosis misdiagnosed initially as cerebral metastatic lung cancer. These patients, including two immunocompetent hosts, presented with both pulmonary and cerebral lesions. In all three patients, the diagnosis was based on magnetic resonance imaging with diffusion sequence, apparent diffusion coefficient reconstruction and neurosurgical cerebral biopsies. Treatment with an appropriate antibiotic regimen was prolonged for several months. Progress was favorable with full resolution of the neurological symptoms and the radiological abnormalities. These three cases emphasize the diagnostic challenge of nocardiosis, especially in disseminated disease.
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Absceso Encefálico/complicaciones , Absceso Encefálico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Nocardiosis/complicaciones , Nocardiosis/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Infecciones del Sistema Respiratorio/complicaciones , Infecciones del Sistema Respiratorio/diagnósticoRESUMEN
UNLABELLED: Retrospective studies suggested a benefit of first-line tyrosine kinase inhibitor (TKI) treatment continuation after response evaluation in solid tumors (RECIST) progression in epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) patients. The aim of this multicenter observational retrospective study was to assess the frequency of this practice and its impact on overall survival (OS). The analysis included advanced EGFR-mutated NSCLC patients treated with first-line TKI who experienced RECIST progression between June 2010 and July 2012. Among the 123 patients included (67 ± 12.7 years, women: 69 %, non smokers: 68 %, PS 0-1: 87 %), 40.6 % continued TKI therapy after RECIST progression. There was no difference between the patients who did and did not continue TKI therapy with respect to progression-free survival (PFS1: 10.5 versus 9.5 months, p = 0.4). Overall survival (OS) showed a non-significant trend in favor of continuing TKI therapy (33.0 vs. 21.2 months, p = 0.054). Progressions were significantly less symptomatic in the TKI continuation group than in the discontinuation group (18 % vs. 37 %, p < 0.01). Univariate analysis showed a higher risk of death among patients with PS >1 (HR 4.33, 95 %CI: 2.21-8.47, p = 0.001), >1 one metastatic site (HR 1.96, 95 %CI: 1.06-3.61, p = 0.02), brain metastasis (HR 1.75, 95 %CI: 1.08-2.84, p = 0.02) at diagnosis, and a trend towards a higher risk of death in cases of TKI discontinuation after progression (HR 1.62, 95 %CI: 0.98-2.67, p = 0.056 ). In multivariate analysis only PS >1 (HR 6.27, 95 %CI: 2.97-13.25, p = 0.00001) and >1 metastatic site (HR 2.54, 95 %CI: 1.24-5.21, p = 0.02) at diagnosis remained significant. This study suggests that under certain circumstances, first-line TKI treatment continuation after RECIST progression is an acceptable option in EGFR-mutated NSCLC patients. CLINICAL TRIAL INFORMATION: NCT02293733.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Anciano , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/patología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Receptores ErbB/genética , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/patología , Masculino , Mutación , Estudios RetrospectivosRESUMEN
INTRODUCTION: Laparoscopy has become the gold-standard approach for excision of benign adrenal tumors but the question of its safety for malignant lesions is still controversial. Our aim was to evaluate the oncologic outcome of laparoscopic adrenalectomy for adrenal metastasis and to look for predictors of a negative surgical outcome. PATIENTS AND METHODS: We retrospectively reviewed the charts of all patients who underwent laparoscopic adrenalectomy for suspicion of adrenal metastasis between 2007 and 2013 at a single academic institution. Recurrence-free survival (RFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier method. Univariate analysis was performed to determine risk factors of negative surgical outcome (positive surgical margins, complications, conversion, significant blood loss) and predictors of RFS and CSS. RESULTS: Thirteen patients underwent 14 laparoscopic adrenalectomies. All patients were operated by a single highly experienced surgeon. Complications occurred in 2 patients (15%): 2 blood transfusions (Clavien-score=2). There were 3 positive surgical margins (21%). Mean length of hospital stay was 4.3 days. Unadjusted RFS and CSS were respectively 48.4% and 83.3% at 1 year, 39.5% and 66.7% at 5 years. In univariate analysis, tumor size was the only risk factor of complication (P=.009) and conversion (P=0.009). Capsule invasion and tumor size were risk factors of positive surgical margins (P=0.01 and P<0.0001). One hundred percent of complications, conversion and positive surgical margins occurred in tumor>7.5 cm on preoperative CT-scan. No predictors of RFS and CSS was found in univariate analysis. CONCLUSION: Laparoscopic adrenalectomy for adrenal metastasis achieves good surgical and oncologic outcomes. When performed by highly experienced surgeon, complications and positive surgical margins occur only in tumors>7.5 cm. These patients may benefit from an open surgical approach.
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Neoplasias de las Glándulas Suprarrenales/secundario , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Laparoscopía/efectos adversos , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/mortalidad , Adrenalectomía/efectos adversos , Anciano , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea/estadística & datos numéricos , Conversión a Cirugía Abierta , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Registros Médicos , Persona de Mediana Edad , Invasividad Neoplásica , Cintigrafía , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Thymic epithelial tumors (TET), including thymomas and thymic carcinomas, are rare and characterized by very different evolutionary patterns depending on histology and invasion stage. The therapeutic management is not well defined but is a subject of increasing interest. The descriptive and analytic objectives of this retrospective monocentric study were to analyze the clinical characteristics of patients with TET, and to assess the management of these tumors in our centre. METHODS: Adult patients with TET managed in the Rennes university hospital in the period 2000-2011 were selected via the pathology department. Their clinical and pathological features and survival were analyzed retrospectively. RESULTS: Fifty TET were retrieved (46 thymomas and 4 thymic carcinomas). Their clinical and histological features and their invasion stages were concordant with published studies. Their diagnostic and therapeutic managements were also in accordance with current guidelines. In univariate analysis, myasthenia and surgery were associated with better survival rates. CONCLUSION: Management of TET in Rennes university hospital is in accordance with guidelines.
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Neoplasias Glandulares y Epiteliales/diagnóstico , Neoplasias Glandulares y Epiteliales/terapia , Neoplasias del Timo/diagnóstico , Neoplasias del Timo/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Francia , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Concomitant administration of erlotinib with standard chemotherapy does not appear to improve survival among patients with non-small-cell lung cancer (NSCLC), but preliminary studies suggest that sequential administration might be effective. OBJECTIVE: To assess the efficacy and tolerability of second-line sequential administration of erlotinib and docetaxel in advanced NSCLC. METHODS: In an open-label phase II trial, patients with advanced NSCLC, EGFR wild-type or unknown, PS 0-2, in whom initial cisplatin-based chemotherapy had failed were randomized to sequential erlotinib 150 mg/d (day 2-16)+docetaxel (75 mg/m(2) d1) (arm ED) or docetaxel (75 mg/m(2) d1) alone (arm D) (21-day cycle). The primary endpoint was the progression-free survival rate at 15 weeks (PFS 15). Secondary endpoints included PFS, overall survival (OS), the overall response rate (ORR) and tolerability. Based on a Simon optimal two-stage design, the ED strategy was rejected if the primary endpoint was below 33/66 patients at the end of the two Simon stages. RESULTS: 147 patients were randomized (median age: 60±8 years, PS 0/1/2: 44/83/20 patients; males: 78%). The ED strategy was rejected, with only 18 of 73 patients achieving PFS15 in arm ED at the end of stage 2 and 17 of 74 patients in arm D. In arms ED and D, respectively, median PFS was 2.2 and 2.5 months and median OS was 6.5 and 8.3 months. CONCLUSION: Sequential erlotinib and docetaxel was not more effective than docetaxel alone as second-line treatment for advanced NSCLC with wild-type or unknown EGFR status.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Docetaxel , Clorhidrato de Erlotinib , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Quinazolinas/administración & dosificación , Retratamiento , Factores de Riesgo , Taxoides/administración & dosificación , Insuficiencia del Tratamiento , Resultado del TratamientoRESUMEN
The incidence of lung cancer during pregnancy is very low, but it is becoming more frequent in industrialized countries both because of the increase in smoking in young women and because women are becoming pregnant later in life. Usually, the cancer has a poor prognosis due to the presence of metastatic disease at the time of diagnosis. Diagnosis and management are delicate, and should deal with the gestational age, the maternal prognosis, the fetal toxicity of treatments, but also with the worsening of maternal prognosis and the risk of neoplastic cells being transmitted to the fetus in case of delayed treatment. Psychological and ethical considerations complicate the decision process. We present a review of the epidemiology, clinical characteristics, management, and prognosis concerning lung cancer during pregnancy. Finally, it is important to remember that young women with lung cancer should be advised to use a reliable form of contraception.
Asunto(s)
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Complicaciones Neoplásicas del Embarazo/diagnóstico , Complicaciones Neoplásicas del Embarazo/terapia , Anomalías Inducidas por Medicamentos/prevención & control , Anomalías Inducidas por Radiación/prevención & control , Aborto Terapéutico , Adulto , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Lactancia Materna , Anticoncepción , Contraindicaciones , Diagnóstico por Imagen/efectos adversos , Diagnóstico por Imagen/métodos , Manejo de la Enfermedad , Femenino , Feto/efectos de los fármacos , Feto/efectos de la radiación , Humanos , Incidencia , Recién Nacido , Neoplasias Pulmonares/epidemiología , Edad Materna , Intercambio Materno-Fetal , Neoplasias/congénito , Células Neoplásicas Circulantes , Embarazo , Complicaciones Neoplásicas del Embarazo/epidemiología , Resultado del Embarazo , Pronóstico , Radioterapia/efectos adversos , Factores de Riesgo , Fumar/efectos adversos , Fumar/epidemiologíaRESUMEN
BACKGROUND: The aim of this randomized phase II trial was to evaluate the feasibility and activity of weekly gemcitabine (G) followed by erlotinib at disease progression (arm A) versus erlotinib followed by G at progression (arm B) in vulnerable elderly patients with advanced non small-cell lung cancer (NSCLC), selected on the basis of a comprehensive geriatric assessment (CGA). METHODS: Vulnerable elderly chemotherapy-naive patients with stage IIIB/IV NSCLC were selected after a CGA (socioeconomic, cognitive and emotional status, depression, nutritional status, ADL and IADL assessments). The primary endpoint was the time to second progression (TTP2). Overall survival (OS), time to first progression (TTP1) and safety were secondary endpoints. RESULTS: Between May 2006 and January 2010, 21 centers enrolled 100 patients, of whom 94 were eligible. TTP2 was 4.3 and 3.5 months in arm A and arm B, respectively; TTP1 was 2.5 and 2.2 months; and the median OS time was 4.4 and 3.9 months. The respective one-year survival rates were 27.3% and 20%. There was no major unexpected toxicity. CONCLUSION: In vulnerable elderly patients with NSCLC not selected for EGFR expression, both strategies were feasible but had modest efficacy. Further studies are needed to identify elderly patients who should receive palliative care only.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Evaluación Geriátrica , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Clorhidrato de Erlotinib , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Estadificación de Neoplasias , Quinazolinas/administración & dosificación , Resultado del Tratamiento , GemcitabinaRESUMEN
BACKGROUND: Elderly cancer patients form a heterogeneous population in which therapeutic decision-making is often difficult. The aim of this randomised phase II trial was to evaluate the feasibility and activity of weekly docetaxel/gemcitabine (DG) followed by erlotinib after progression (arm A) vs erlotinib followed by DG after progression (arm B) in fit elderly patients with advanced non small-cell lung cancer (NSCLC). METHODS: Elderly chemotherapy-naive patients with stage IIIB/IV NSCLC were selected after a comprehensive geriatric assessment (socioeconomic, cognitive, depression, ADL and IADL assessments). The primary endpoint was the time to second progression (TTP2). Overall survival (OS), the time to first progression (TTP1) and safety were secondary endpoints. RESULTS: Between July 2006 and November 2008, 22 centres enrolled 100 patients. TTP2 was 7.5 and 5.8 months in arm A and arm B, respectively; TTP1 was 4.7 and 2.7 months; and the median OS time was 9.4 and 7.1 months; the respective 1-year survival rates were 36.2 and 31.4%. There was no major unexpected toxicity. CONCLUSION: These results suggest that weekly DG, followed by erlotinib, is a promising treatment for fit elderly patients with NSCLC; the efficacy of the reverse sequence was insufficient to recommend it for EGFR-non-selected patients.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Progresión de la Enfermedad , Docetaxel , Esquema de Medicación , Clorhidrato de Erlotinib , Evaluación Geriátrica , Humanos , Neoplasias Pulmonares/patología , Quinazolinas/administración & dosificación , Taxoides/administración & dosificación , GemcitabinaRESUMEN
Ras genes encode a family of membrane proteins involved in the regulation of cell growth. Mutations of Ras stimulate cell growth and thus can play a role in carcinogenesis. The search for mutations of Ras is possible by PCR on bronchial biopsies or surgical specimens. They are found in 15 to 20% of non-small cell lung cancers. In the disease's early stage, the presence of a Ras mutation can be a negative predictor of the effectiveness of adjuvant chemotherapy. In the advanced stage of the disease, it is a factor predicting a poor prognosis. Although prospective studies have found no statistically significant negative influence of the presence of a mutation of Ras on the effectiveness of tyrosine kinase inhibitors of EGFR, it is likely that these treatments will be of limited value in this population given the lack of response observed when Ras is mutated. Prospective and functional studies are needed to determine the value of the different mutations observed.
Asunto(s)
Genes ras/genética , Neoplasias Pulmonares/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , PronósticoRESUMEN
The occurrence of pain during the course of bronchial carcinoma is nearly inescapable and often constitutes the main symptom for patients and those close to them. While pain control is held to be a priority of care in cancerology in the future, this goal is not always reached due to insufficient implementation of recommendations, however widely accessible. Our aim is to present the different aspects of pain treatment through the details of both pharmacological and nonpharmacological means.
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Analgésicos/uso terapéutico , Carcinoma Broncogénico/fisiopatología , Neoplasias Pulmonares/fisiopatología , Dolor/tratamiento farmacológico , Cuidados Paliativos/métodos , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Terapia Combinada , HumanosAsunto(s)
Neumonía en Organización Criptogénica/diagnóstico por imagen , Alveolos Pulmonares/diagnóstico por imagen , Anticolesterolemiantes/efectos adversos , Dolor en el Pecho/diagnóstico , Neumonía en Organización Criptogénica/inducido químicamente , Diagnóstico Diferencial , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Persona de Mediana Edad , Pravastatina/efectos adversos , Embolia Pulmonar/diagnóstico , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Brain metastases (BM) considerably worsen the prognosis of non-small-cell lung cancer (NSCLC) patients. The usefulness and choice of chemotherapy remain uncertain in this indication since these patients are excluded from most clinical trials. We conducted a phase II study to determine the efficacy and tolerability of up-front chemotherapy with association of temozolomide and cisplatin in NSCLC patients with BM. PATIENTS AND METHODS: Fifty NSCLC patients with BM received temozolomide (200 mg/m(2)/day for 5 days every 28 days) and cisplatin (75 mg/m(2) at day 1 of each cycle), up to six cycles, followed by whole brain radiotherapy (WBRT). An evaluation was carried out every two cycles and after WBRT. WBRT was performed earlier in case of progressive disease at any time or stable disease after cycle 4. RESULTS: Eight objective responses were achieved (16%). Overall median survival was 5 months. Median time to progression was 2.3 months. Ten patients (20%) presented a grade 3/4 neutropenia and 11 patients (22%) presented a grade 3/4 thrombopenia. CONCLUSION: This study demonstrates a lack of efficacy of up-front chemotherapy with association of temozolomide and cisplatin in these patients. Nevertheless, it supports the feasibility of chemotherapy before brain radiotherapy in NSCLC patients with BM.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Dacarbazina/administración & dosificación , Dacarbazina/efectos adversos , Dacarbazina/análogos & derivados , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Temozolomida , Resultado del TratamientoRESUMEN
B cell receptor (BcR) signaling requires a tight regulation of several protein tyrosine kinases and phosphatases, and associated co-receptors. Mounting evidence indicates that abnormal BcR signaling, such as occurs in SHP-1 and Lyn-deficient mice, results in production of pathogenic autoantibodies and lupus-like glomerulonephritis, suggesting that altered signaling thresholds could underlie the development of systemic autoimmunity. To test this hypothesis, we investigated expression of BcR-associated signaling molecules in lymphocytes from patients with systemic lupus erythematosus (SLE) during inactive phases of the disease. We found that the transmembrane regulatory protein tyrosine phosphatase CD45 is expressed at abnormal levels. Strikingly, this reduction persisted during four months of follow-up. By contrast, despite its potent role as a regulator of thymus-independent immune responses and of B cell life span, the CD22 co-receptor is expressed at normal levels in B lymphocytes isolated ex vivo from SLE patients. We also noted unusual levels of the cytosolic protein tyrosine kinase Lyn and the protein tyrosine phosphatase SHP-1 in the lymphocytes of the patients. Since in normal B cells Lyn and SHP-1 act in concert within a common negative pathway in which CD45 counteracts SHP-I regulatory role, we propose that this feedback regulatory pathway is crippled to different degrees in human SLE B cells. Break of the balance between positive and negative signaling molecules likely modifies the BcR signaling thresholds. Such alterations, together with other factors, may contribute to the disruption of self-tolerance in this disease.
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Moléculas de Adhesión Celular , Lectinas , Lupus Eritematoso Sistémico/inmunología , Receptores de Antígenos de Linfocitos B/metabolismo , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos B/metabolismo , Linfocitos B/enzimología , Linfocitos B/inmunología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Antígenos Comunes de Leucocito/metabolismo , Lupus Eritematoso Sistémico/enzimología , Activación de Linfocitos , Ratones , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Proteínas Tirosina Fosfatasas/metabolismo , Autotolerancia , Lectina 2 Similar a Ig de Unión al Ácido Siálico , Transducción de Señal , Familia-src Quinasas/metabolismoRESUMEN
The objectives were to provide estimates of the prevalence of autoantibody (Ab) directed to CD45 in lupus patients, identify the target autoantigen(s), and determine the ability of such reactivity to mediate neutralization of T lymphocytes. Sera from 64 patients were studied using 2 assays: Western blot and an ELISA with CD45 eluted from 3 cell lines as antigen (U937, Jurkat and Daudi). The role of carbohydrate specificity was investigated using enzyme digestion of blotted glycans, competition with sugars, and inhibition with lectins. Apoptosis was studied through annexin V binding, and cell cycle analysis using the propidium iodide method. AutoAb to CD45 were detected in 16/64 sera (25%) by Western blot, and 21/32 sera (66%) found positive in the ELISA. CD45 purified from Daudi cells was identified in the ELISA, but not in the blot. AutoAb were of the IgM and the IgG isotypes, but not specific for a particular cell type or CD45 isoform: 2 dominant specificities were recognized, one against p180, and another against high MW isoforms. Neuraminidase-induced enhancement of reactivity, together with the inhibitory effect of N-acetyl galactosamine and Dolichos diflorus lectin suggest that the epitopes are carbohydrates. AutoAb which were specific for activated CD4+T cells triggered the annexin V binding, and, in 2 of 4 cases, lymphocytes underwent apoptosis. In conclusion, carbohydrate conformational epitopes may be important as target antigens, and some CD45 autoAb have the capacity to neutralize activated T cells through anergy or apoptosis.
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Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Antígenos Comunes de Leucocito/inmunología , Lupus Eritematoso Sistémico/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Anticuerpos Monoclonales , Sitios de Unión de Anticuerpos , Linfoma de Burkitt , Ensayo de Inmunoadsorción Enzimática , Humanos , Células Jurkat , Lupus Eritematoso Sistémico/sangre , Valores de Referencia , Células Tumorales Cultivadas , Células U937RESUMEN
CD45RO+ T cells are referred to as memory or helper-inducer while CD45RA+ T cells are regarded as naive or suppressor-inducer T cells. The former population predominates in the peripheral blood and even more in the synovial fluid of patients with rheumatoid arthritis, to the expense of the latter population. Within the CD45RB+ compartment, there appears to be more of the fully-differentiated than of the early-differentiated CD4+ T cells. In spite of the fact that these lymphocytes are close to undergoing apoptosis, this programmed cell death is inhibited in the rheumatoid synovium.
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Artritis Reumatoide/inmunología , Antígenos Comunes de Leucocito/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Humanos , Inmunofenotipificación , Antígenos Comunes de Leucocito/metabolismo , Isoformas de Proteínas/inmunología , Isoformas de Proteínas/metabolismo , Linfocitos T/inmunología , Distribución Tisular , Receptor fas/inmunologíaRESUMEN
The CD5 molecule is expressed by a B cell subset. We have demonstrated that resting B cells do not proliferate in response to CD5 ligation, whereas cells preactivated with anti-IgM and IL-2 do so. Here, we specifically studied the effects of anti-CD5 and anti-IgM on apoptosis of CD5+ B cells. Both ligation of CD5 or of surface IgM (sIgM) resulted in apoptosis. This started earlier following ligation of CD5 than with sIgM, and both responses were time dependent. CD5-induced apoptosis was independent of the epitope recognized or the way the antibody was presented to the B cells. CD5+ B cells were more sensitive to IgM-induced apoptosis than CD5 B cells. Engagement of CD5 or CD3 expressed by T cells failed to induce apoptosis. Our data indicate differences in the function of CD5 molecules on tonsillar B cells, compared with blood T cells and suggest that cross-linking CD5 on B cell activates specific pathways responsible for apoptosis.
Asunto(s)
Apoptosis/inmunología , Linfocitos B/inmunología , Antígenos CD5/inmunología , Linfocitos T/inmunología , Linfocitos B/patología , Células Cultivadas , Humanos , Ligandos , Linfocitos T/patologíaRESUMEN
Western blotting with U937 cell extracts as the substrate, and enzyme-linked immunosorbent assays (ELISA) with U937-, Jurkat- and Daudi cell-purified CD45 molecules were used to detect anti-CD45 reactivity in patients with systemic lupus erythematosus (SLE). By immunoblotting, 16 of 64 SLE sera were shown to be positive (25.0%). In the ELISAs, 13 out of 18 SLE sera reacted with the target CD45. Of these, three were not detectable on the blot. Importantly, 12 of these ELISA-positive sera contained IgM and IgG auto-antibodies. Neuraminidase-treatment of U937-precipitated CD45 molecules enhanced the reactivity to most of the isoforms, indicating that the antibodies may bind to asialylated polysaccharides.