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991.
Quantitative analysis of bcl-2 expression in normal and leukemic human B-cell differentiation. 总被引:5,自引:0,他引:5
P Menendez A Vargas C Bueno S Barrena J Almeida M De Santiago A López S Roa J F San Miguel A Orfao 《Leukemia》2004,18(3):491-498
Lack of apoptosis has been linked to prolonged survival of malignant B cells expressing bcl-2. The aim of the present study was to analyze the amount of bcl-2 protein expressed along normal human B-cell maturation and to establish the frequency of aberrant bcl-2 expression in B-cell malignancies. In normal bone marrow (n=11), bcl-2 expression obtained by quantitative multiparametric flow cytometry was highly variable: very low in both CD34(+) and CD34(-) B-cell precursors, high in mature B-lymphocytes and very high in plasma cells. Bcl-2 expression of mature B-lymphocytes from peripheral blood (n=10), spleen (n=8) and lymph node (n=5) was significantly higher (P<0.02) in CD23(-) as compared to CD23(+) B cells, independent of the type of tissue analyzed. Upon comparison with normal human B-cell maturation, bcl-2 expression in neoplastic B cells from 144 patients was found to be aberrant in 66% of the cases, usually corresponding to bcl-2 overexpression (63%). Follicular lymphoma (FL) carrying t(14;18) and MALT lymphoma were the only diagnostic groups constantly showing overexpression of bcl-2. Bcl-2 overexpression was also frequently found in precursor B-acute lymphoblastic leukemia (84%), typical (77%) and atypical (75%) B-cell chronic lymphocytic leukemia, prolymphocytic leukemia (two of three cases), mantle cell lymphoma (55%), but not in t(14;18)(-) FL, splenic marginal zone lymphoma, Burkitt lymphoma and multiple myeloma. 相似文献
992.
Prognostic value of CD40 in adult soft tissue sarcomas. 总被引:4,自引:0,他引:4
Alessandro Ottaiano Anna De Chiara Francesco Perrone Gerardo Botti Flavio Fazioli Vincenzo De Rosa Nicola Mozzillo Vincenzo Ravo Brunello Morrica Ciro Gallo Carmela Pisano Maria Napolitano Paolo Antonio Ascierto Rosario Vincenzo Iaffaioli Gaetano Apice 《Clinical cancer research》2004,10(8):2824-2831
PURPOSE: The purpose is to evaluate the expression of CD40, a membrane protein predominantly expressed on B cells, dendritic cells, and macrophages, in a series of adult soft tissue sarcomas and to test its possible prognostic value. EXPERIMENTAL DESIGN: CD40 expression was studied by immunohistochemistry. Correlations with other baseline characteristics of patients and tumors were analyzed with chi(2) test. The prognostic value was studied with univariable and multivariable analysis adjusted by age, sex, tumor size, grade, location, and distant metastases. RESULTS: Eighty-two patients, between January 1994 and May 2001, were analyzed. Membrane or cytoplasmic staining for CD40 protein was absent in 30% of the tumors but present in <10% of cells in 22 (27%), in 10% to 50% in 23 (28%), and in >50% of cells in 12 (15%) tumors. There was no correlation between CD40 expression and age, sex, size, grade, and location of the primary tumor and distant metastases. With 61 patients (74.4%) progressed and 31 (37.8%) dead, CD40 expression was a significant prognostic factor for disease-free and overall survival at univariable and multivariable analysis. Patients with tumors expressing CD40 in >50% of cells had a dramatically unfavorable prognosis with median disease-free and overall survival of 7 and 17 months, respectively, and hazard ratios of relapse and death as compared with patients with CD40-negative tumors of 2.89 (95% confidence interval: 1.26-6.60) and 6.92 (95% confidence interval: 2.18-22.0), respectively. CONCLUSIONS: These data suggest that expression of CD40 protein in >50% of cells might indicate an unfavorable prognosis in adult soft tissue sarcomas. 相似文献
993.
994.
Donato Gemmati Alessia Ongaro Gian L Scapoli Matteo Della Porta Silvia Tognazzo Maria L Serino Eros Di Bona Francesco Rodeghiero Giuseppe Gilli Roberto Reverberi Angelo Caruso Michela Pasello Agnese Pellati Monica De Mattei 《Cancer epidemiology, biomarkers & prevention》2004,13(5):787-794
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation. 相似文献
995.
In vitro assessment of the efficacy of thermal therapy in human benign prostatic hyperplasia. 总被引:3,自引:0,他引:3
P Bhowmick J E Coad S Bhowmick J L Pryor T Larson J De La Rosette J C Bischof 《International journal of hyperthermia》2004,20(4):421-439
The successful management of BPH with minimally invasive thermal therapies requires a firm understanding of the temperature-time relationship for tissue destruction. In order to accomplish this objective, the present in vitro study assesses the cellular viability of human BPH tissue subjected to an experimental matrix of different temperature-time combinations. Hyperplastic prostate tissue was obtained from 10 radical prostatectomy specimens resected for adenocarcinoma. A portion of hyperplastic tissue from the lateral lobe of each prostate was sectioned into multiple 1 mm thick tissue strips, placed on a coverslip and thermally treated on a controlled temperature copper block with various temperatures (45-70 degrees C) for various times (1-60 min). After heat treatment, the tissue slices were cultured for 72 h and viability was assessed using two independent assays: histology and dye uptake for stromal tissue and using histology alone for the glandular tissue. The hyperplastic human prostate tissue showed a progressive histological increase in irreversible injury with increasing temperature-time severity. The dye uptake and histology results for stromal viability were similar for all temperature-time combinations. In vitro thermal injury showed 85-90% stromal destruction (raw data) of human BPH for temperature-time combinations of 45 degrees C for 60 min, 50 degrees C for 30 min, 55 degrees C for 5 min, 60 degrees C for 2 min and 70 degrees C for 1 min. Apoptosis was also identified in the control and milder treated tissues with the degree of glandular apoptosis (about 20%) more than that seen in the stromal regions (< 5%). The Arrhenius model of injury was fitted to the data for conditions leading to a 90% drop in viability (normalized to control) obtained for stromal tissue. The activation energies (E) were 40.1 and 38.4 kcal/mole for the dye uptake study and histology, respectively, and the corresponding frequency factors (A) were 1.1 x 10(24) and 7.78 x 10(22)/s. This study presents the first temperature-time versus tissue destruction relation for human BPH tissue. Moreover, it supports the concept that higher temperatures can be used for shorter durations to induce tissue injury comparable with the current clinically recommended lower temperature-longer time treatments (i.e. 45 degrees C for 60 min) for transurethral microwave thermotherapy of the prostate. 相似文献
996.
Katrien De Jaeger M.D. M.Sc. Yvette Seppenwoolde Ph.D. Harm H. Kampinga Ph.D. Liesbeth J. Boersma M.D. Ph.D. Jos S. A. Belderbos M.D. Joos V. Lebesque M.D. Ph.D. 《International journal of radiation oncology, biology, physics》2004,58(5):27-1387
PURPOSE: In dose-escalation studies of radiotherapy (RT) for non-small-cell lung cancer (NSCLC), radiation pneumonitis (RP) is the most important dose-limiting complication. Transforming growth factor-beta1 (TGF-beta1) has been reported to be associated with the incidence of RP. It has been proposed that serial measurements of plasma TGF-beta1 can be valuable to estimate the risk of RP and to decide whether additional dose-escalation can be safely applied. The aim of this study was to evaluate prospectively the time course of TGF-beta1 levels in patients irradiated for NSCLC in relation to the development of RP and dose-volume parameters. METHODS AND MATERIALS: Plasma samples were obtained in 68 patients irradiated for medically inoperable or locally advanced NSCLC (dose range, 60.8-94.5 Gy) before and 4, 6, and 18 weeks after the start of RT. Plasma TGF-beta1 levels were determined using a bioassay on the basis of TGF-beta1-induced plasminogen activator inhibitor-1 expression in mink lung cells. All patients underwent chest computed tomography scans before RT that were repeated at 18 weeks after RT. The computed tomography data were used to calculate the mean lung dose (MLD) and to score the radiation-induced radiologic changes. RP was defined on the basis of the presence of either radiographic changes or clinical symptoms. Symptomatic RP was scored according to the Common Toxicity Criteria (Grade 1 or worse) and the Southwestern Oncology Group criteria (Grade 2 or worse). Multivariate analyses were performed to investigate which factors (pre- or posttreatment TGF-beta1 level, MLD) were associated with the incidence of RP. To improve our understanding of the time course of TGF-beta1 levels, we performed a multivariate analysis to investigate which factors (pre-RT TGF-beta1 level, MLD, RP) were independently associated with the posttreatment TGF-beta1 levels. RESULTS: The pre-RT TGF-beta1 levels were increased in patients with NSCLC (median 21 ng/mL, range, 5-103 ng/mL) compared with healthy individuals (range, 4-12 ng/mL). On average, the TGF-beta1 levels normalized toward the end of treatment and remained stable until 18 weeks after RT. In 29 patients, however, TGF-beta1 was increased at the end of RT with respect to the pre-RT value. The multivariate analyses revealed that the MLD was the only variable that correlated significantly with the risk of both radiographic RP (p = 0.05) and symptomatic RP, independent of the scoring system used (p = 0.05 and 0.03 for Southwestern Oncology Group and Common Toxicity Criteria systems, respectively). The TGF-beta1 level at the end of RT was significantly associated with the MLD (p <0.001) and pre-RT TGF-beta1 level (p = 0.001). CONCLUSION: The MLD correlated significantly with the incidence of both radiographic and symptomatic RP. The results of our study did not confirm the reports that increased levels of TGF-beta1 at the end of RT are an independent additional risk factor for developing symptomatic RP. However, the TGF-beta1 level at the end of a RT was significantly associated with the MLD and the pre-RT level. 相似文献
997.
Besançon-Watelet C De March AK Renoult E Kessler M Béné MC Faure GC Sarda MN 《Transplantation》2000,69(3):366-371
BACKGROUND: Cytomegalovirus (CMV) infection or reactivation is a frequent complication of renal transplantation. Diagnosis of these conditions relies on the detection of circulating antigen, or of specific IgM and/or IgG, which develop over several weeks. Evocative clinical features may be detected earlier, but lack specificity. Rapid and early changes in the partition of lymphocyte subsets could be an additional indication of pending CMV infection. METHODS: A systematic follow-up of peripheral B lymphocytes identified immunophenotypically by the determination of surface immunoglobulins (sIg), performed in 97 kidney transplant recipients, allowed to identify transient increases apparently predictive of CMV primo-infection or reactivation over the next 3 months. To better define the nature of these B cells, an extended investigation was performed for 14 prospective patients. In addition to surface Ig, membrane CD19, HLA-DR, and CD80 expression were explored. The cytoplasmic presence of mu, kappa, and lambda chains was also examined. B cell function was investigated using the ELISPOT technique, which allows an enumeration of the populations of IgG, IgA, and IgM secreting B cells. RESULTS: Retrospective analysis of the clinical outcome of the cohort of 97 patients evidenced that early transient increases in B cell levels were significantly (P<0.0001) associated with CMV infection. The same trend was noted in the smaller series of patients who benefited from a more extensive investigation of B cells, 10 of whom presented clinical or biological signs of CMV infection. Mature B cells, expressing surface Ig, CD19, DR, and CD80 are those presenting transient increases. No significant variation of preB (cmu+/kappalambda-) or activated (spot-forming) cells was evidenced in these patients. CONCLUSION: Individual examination of each patient's immune reconstitution profile allows to detect transient peaks of mature B cell during the initial immunosuppressive therapy, that appear to be predictive of oncoming CMV infection or reactivation. 相似文献
998.
999.
Acierno R Kilpatrick DG Resnick H Saunders B De Arellano M Best C 《Journal of traumatic stress》2000,13(3):381-396
A national household probability sample of 4,023 adolescents aged 12 to 17 years was surveyed by telephone via structured clinical interview to determine the impact of familial substance use, sexual and physical assault, witnessed violence, depression and posttraumatic stress disorder (PTSD) on risk of smoking. Results indicated that familial substance use increased risk of smoking only for boys and sexual assault or depression increased risk of smoking only for girls. Age, Caucasian ethnicity, and experiencing physical assault or witnessing violence elevated risk of current cigarette use for both genders. By contrast, PTSD per se was not associated with increased risk of smoking, after the effects of other variables were controlled. 相似文献
1000.
Alberto Garaventa Roberto Luksch Maria Serena Lo Piccolo Elena Cavadini Paolo G Montaldo Maria Rosa Pizzitola Luca Boni Mirco Ponzoni Andrea Decensi Bruno De Bernardi Franca Fossati Bellani Franca Formelli 《Clinical cancer research》2003,9(6):2032-2039
PURPOSE: Fenretinide (4HPR), a synthetic retinoid, induces apoptosis in neuroblastoma cells. A Phase I study in children with neuroblastoma was designed to determine maximum tolerated dose, toxicity, and pharmacokinetics. EXPERIMENTAL DESIGN: Fifty-four patients received oral 4HPR, once daily, for 28 days, followed by a 7-day interruption, for up to 6 courses. The starting dose was 100 mg/m(2)/day. At least 3 patients were entered at each escalating 4HPR dose level. Pharmacokinetic sampling was performed on days 1 and 28 of the first course. RESULTS: Fifty-four patients, of whom 53 were evaluable, received doses between 100 and 4000 mg/m(2)/day for a total of 168 courses. Additional dose escalation was precluded by capsule number intake. A total of 34 of 53 evaluable patients showed manageable, reversible toxicities, which were not dose related. One dose-limiting toxicity (nyctalopia grade 3) occurred after the 1000 mg/m(2)/day dose. Twelve patients showed grade 2 toxicity: skin xerosis (6 cases); nyctalopia (3 cases); hepatic toxicity (1 case); diarrhea (1 case); and headache (1 case). Stable disease was observed in 41 patients for a median period of 23 months (range 2-35+). After first administration, average 4HPR peak plasma levels ranged from 0.6 to 6 micro M (after 100 and 4000 mg/m(2)/day, respectively) and increased 2-fold (to 1.3 and 12.9 micro M, respectively) after the 28-day treatment. 4HPR half-life increased from 17 h after the first administration to 25 h after the 28(th) administration. Incidence of grade 2-3 toxicity was 0 of 12 (0%), 7 of 22 (31%), and 4 of 8 (50%) with peak 4HPR concentrations <3 micro M, 3-10 micro M, and >10 micro M, respectively. After repeated treatment, retinol levels decreased from 20 to 10% of pretreatment levels after all of the doses. CONCLUSIONS: In children, 4HPR administration up to 4000 mg/m(2)/day over 28 days, followed by a 7-day interruption, results in manageable toxicity and in drug plasma concentrations comparable with those that induce apoptosis in neuroblastoma cell lines. 相似文献