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Emili Montserrat

Publications and source records attributed to Emili Montserrat.

At least 19 recordsLinked to original sources

Molecular diagnosis of primary mediastinal B cell lymphoma identifies a clinically favorable subgroup of diffuse large B cell lymphoma related to Hodgkin lymphoma.

Using current diagnostic criteria, primary mediastinal B cell lymphoma (PMBL) cannot be distinguished from other types of diffuse large B cell lymphoma (DLBCL) reliably. We used gene expression profiling to develop a more precise molecular diagnosis of PMBL. PMBL patients were considerably younger than other DLBCL patients, and their lymphomas frequently involved other thoracic structures but not extrathoracic sites typical of other DLBCLs. PMBL patients had a relatively favorable clinical outcome, with a 5-yr survival rate of 64% compared with 46% for other DLBCL patients. Gene expression profiling strongly supported a relationship between PMBL and Hodgkin lymphoma: over one third of the genes that were more highly expressed in PMBL than in other DLBCLs were also characteristically expressed in Hodgkin lymphoma cells. PDL2, which encodes a regulator of T cell activation, was the gene that best discriminated PMBL from other DLBCLs and was also highly expressed in Hodgkin lymphoma cells. The genomic loci for PDL2 and several neighboring genes were amplified in over half of the PMBLs and in Hodgkin lymphoma cell lines. The molecular diagnosis of PMBL should significantly aid in the development of therapies tailored to this clinically and pathogenetically distinctive subgroup of DLBCL.

Adult↗

ZAP-70 expression as a surrogate for immunoglobulin-variable-region mutations in chronic lymphocytic leukemia.

BACKGROUND: The mutational status of immunoglobulin heavy-chain variable-region (IgVH) genes in the leukemic cells of chronic lymphocytic leukemia (CLL) is an important prognostic factor in the disease. We investigated whether the expression of ZAP-70 by CLL cells correlated with the IgVH mutational status, disease progression, and survival. METHODS: The expression of ZAP-70 was analyzed in T-cell and B-cell lines and in peripheral-blood samples from 56 patients with CLL with the use of flow cytometry, Western blotting, and immunohistochemistry. The results were correlated with the IgVH mutational status and clinical outcome. RESULTS: ZAP-70 was detected by flow-cytometric analysis in cells of T-cell lineage and in leukemic cells from 32 of 56 patients with CLL. In all patients in whom at least 20 percent of the leukemic cells were positive for ZAP-70, IgVH was unmutated, whereas IgVH mutations were found in 21 of 24 patients in whom less than 20 percent of the leukemic cells were positive for ZAP-70 (P<0.001). Concordant results were obtained when ZAP-70 expression was assessed by immunohistochemistry or Western blotting. The level of ZAP-70 expression did not change over time (median, 37 months) in sequential samples from 30 patients with CLL. Patients with Binet stage A CLL who had at least 20 percent ZAP-70-positive leukemic cells had more rapid progression and poorer survival than those with less than 20 percent ZAP-70-positive cells. CONCLUSIONS: Among patients with CLL, expression of ZAP-70, as detected by flow-cytometric analysis, correlated with IgVH mutational status, disease progression, and survival.

ADP-ribosyl Cyclase↗

Mechanism of action and resistance to monoclonal antibody therapy.

Monoclonal antibodies (MoAbs) are increasingly used in the treatment of patients with hematological malignancies and autoimmune diseases. The most commonly employed humanized and chimeric MoAbs are rituximab, alemtuzumab (Campath-1H, Ilex Pharmaceuticals, San Antonio, TX), and gemtuzumab-ozogamicin (Mylotarg, Wyeth-Ayerst Laboratories, St Davids, PA). The mechanism of action of these antibodies, and host and cellular factors influencing the response, are not completely known. Induction of apoptosis, antibody-dependent cell cytotoxicity (ADCC), and complement-mediated cell death (CDC) is the proposed mechanism of action of these antibodies. We review the current understanding of the mechanism of action of and resistance to these MoAbs.

Alemtuzumab↗

Salvage treatment with etoposide (VP-16), ifosfamide and cytarabine (Ara-C) for patients with recurrent primary central nervous system lymphoma.

BACKGROUND: Survival of patients with primary central nervous system lymphoma (PCNSL) has improved with methotrexate-based combination regimens and radiotherapy (RT). However, the prognosis of patients who fail or relapse after initial response is poor. Very little data is available on salvage treatment at recurrence. PATIENTS AND METHODS: Sixteen immunocompetent patients (13 males/three females, median age 54 yr) with refractory (one patient) or recurrent (15 patients) PCNSL, homogeneously treated at diagnosis with the cyclophosphamide, doxorubicin, vincristine, dexamethasone/carmustine, vincristine, cytarabine and methotrexate (CHOD/BVAM) and RT regimen, received etoposide (VP-16), ifosfamide and cytarabine (Ara-C) (VIA) chemotherapy as a salvage treatment. VIA included etoposide 100 mg/m2/d days 1-3, ifosfamide 1000 mg/m2/d days 1-5, and cytarabine 2000 mg/m2/12 h day 1. The therapy was repeated every 28 d for a total of planned six cycles. RESULTS: Median time between first complete response (CR) and relapse was 19 months (range: 6-46 months). Thirteen patients (81%) had a performance status <or=2, six had multifocal PCNSL and six (of eight tested) positive cerebrospinal fluid cytology. The median number of courses per patient was four (range: 1-6). Five patients completed the whole VIA therapy. Six patients (37%) achieved CR. After a median follow-up of 15 months for surviving patients, two have relapsed, with a median failure-free survival of 5 months. Twelve patients have died from progression of PCNSL, with a 12-month overall survival of 41% [95% confidence interval (CI): 16-66]. The major toxicity was World Health Organization grade 2-4 neutropenia (69% of patients) and thrombocytopenia (50%). Five patients had grade 3-4 infectious complications. Finally, one patient developed a severe but reversible ifosfamide encephalopathy. CONCLUSION: The data presented show that the chemotherapy VIA is an effective salvage regimen for patients with recurrent PCNSL.

Adolescent↗

Rituximab in chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia but is currently incurable by conventional therapeutic interventions. Rituximab has proven efficacy and tolerability in non-Hodgkin's lymphoma, achieving response rates of 73% and 48% in previously untreated or relapsed/refractory indolent non-Hodgkin's lymphoma, respectively. However, the standard dose and schedule (375 mg/m(2) once-weekly for 4 weeks) may not be optimal for patients with previously treated small lymphocytic lymphoma, the lymphomatous equivalent of CLL. Nevertheless, good response rates have been achieved in untreated CLL and small lymphocytic lymphoma using the standard dose and schedule and also using higher or more frequent dosing, indicating that rituximab is an active agent in this setting. More recently, the combination of rituximab and fludarabine or fludarabine-containing regimens has yielded overall response rates of 95%, with complete response rates up to 66% in previously untreated CLL. These response rates are among the highest achieved by any regimen in CLL. These studies indicate that immunochemotherapy with rituximab may offer improved outcomes for patients with CLL. Semin Oncol 30 (suppl 2):34-39.

Antibodies, Monoclonal↗

Appropriateness of applying the response criteria for multiple myeloma to Waldenstrom's macroglobulinemia?

Since the presence of an M-component is an essential disease feature in both multiple myeloma (MM) and Waldenstrom's macroglobulinemia (WM), the decrease in the M-protein size applied for response in MM is also a crucial criteria for assessing response in WM. However, WM frequently displays lymphoma-like features that should be included in the response criteria.

Antineoplastic Agents↗

Incidence and clinical significance of bcl-2/IgH rearrangements in follicular lymphoma.

Bcl-2/IgH rearrangement is the molecular hallmark of follicular lymphoma (FL) which is present in 70-90% of the cases at diagnosis. The clinical significance of this feature is controversial. The aim of this study was to analyze the bcl-2/IgH rearrangement by means of a PCR technique, and to correlate molecular findings with clinical characteristics and outcome. Sixty-nine patients (median age, 53 years; male/female ratio: 35/34) diagnosed with FL in a single institution were included in the study. A total of 77 DNA samples were analyzed, 54 were obtained from lymph node biopsy and 23 from peripheral blood or bone marrow. Bcl-2/IgH rearrangement was assessed for both the major breakpoint region (MBR) and the minor cluster region (mcr) breakpoints by a PCR technique. Thirty-nine out of sixty patients (65%) with assessable samples were found to have a bcl-2/IgH rearrangement in the MBR breakpoint, whereas bcl-2/IgH rearrangement in mcr was observed in one patient (2%) and no rearrangement at MBR or mcr in the remaining 20 patients (33%). Regarding the initial characteristics, patients with bcl-2/IgH rearrangements at MBR or mcr were younger (<65 years) than those with no rearrangement at these sites (p = 0.0001). No differences were found according to bcl-2/IgH rearrangement in terms of complete response rate, time to treatment failure and overall survival. In our series bcl-2/IgH rearrangement at MBR or mcr, which was found in 67% of the patients, was not correlated with response to treatment, survival nor time-to-treatment-failure.

Aged↗

CD34+ selected autologous peripheral blood stem cell transplantation for multiple sclerosis: report of toxicity and treatment results at one year of follow-up in 15 patients.

BACKGROUND AND OBJECTIVES: Autologous stem cell transplantation (ASCT) is currently being evaluated as a therapy for patients with multiple sclerosis (MS). We report the results of a phase II trial to evaluate feasibility and toxicity of CD34+ selected ASCT (CD34+/ASCT) and treatment results at one year of follow-up. DESIGN AND METHODS: Patients with advanced secondary progressive (SP) or relapsing-remitting (RR) MS and confirmed worsening of the extended disability status scale (EDSS) in the previous year despite interferon or other immunotherapies were included. Peripheral blood stem cells were obtained by leukaphereses after mobilization with cyclophosphamide (Cy) and granulocyte colony-stimulating factor (G-CSF). CD34+ selection was performed by means of an Isolex 300 or CliniMACS device. BCNU, Cy and antithymocyte globulin (ATG) were administered as conditioning regimen. RESULTS: Fifteen patients (9 SPMS and 6 RRMS) with a median EDSS of 6.0 (4.5-6.5) and a median of 3 (1-7) relapses in the previous year were included. Mobilization was unsuccessful in one patient. During mobilization, one patient had a transient neurologic deterioration. The main complication during ASCT were engraftment syndrome, which developed in three patients, CMV reactivation in one, and neurologic deterioration in two patients coinciding with high-fever related to ATG. Hematologic recovery was fast and complete in all cases. At 12 months, the EDSS had improved in three patients, worsened in two and remained stable in nine. Despite withdrawal of all immunosuppressive therapy only two patients had relapses. Magnetic resonance imaging showed disappearance of enhanced T1 lesions but oligoclonal bands persisted in the cerebrospinal fluid of all evaluated cases. INTERPRETATION AND CONCLUSIONS: CD34+/ASCT using BCNU, Cy and ATG as conditioning regimen has an acceptable toxicity and clearly reduces the progression of MS. Further follow-up is necessary to establish the real impact of this procedure on the long-term evolution of the disease.

Adult↗

International and Italian prognostic indices in follicular lymphoma.

BACKGROUND AND OBJECTIVES: The International Prognostic Index (IPI), initially designed for aggressive lymphomas, has been successfully used in patients with follicular lymphoma (FL). The Italian Lymphoma Intergroup (ILI) created a new prognostic index specific for FL. The aim of this study was to compare which of these two indices is more useful when applied to a large group of FL patients. DESIGN AND METHODS: Both indices, IPI (age >60 years, extranodal involvement >=2 sites, elevated lactate dehydrogenase, ECOG >=2, stage >=3) and ILI (age >60 years, extranodal involvement >=2 sites, elevated lactate dehydrogenase, male sex, B symptoms, erythrocyte sedimentation rate >=30 mm 1(st) hour) were calculated in a group of 398 FL patients. Overall survival (OS) and progression-free survival (PFS) associated with each prognostic group were calculated according to the Kaplan-Meier method. RESULTS: The overall concordance between both indices was 73%. According to the IPI 122 patients (31%) were in the higher risk group, whereas according to the ILI 132 (33%) were; concordance between the high risk groups was 66%. The 10-years OS and PFS rates after applying the IPI system were 73% and 37%, respectively, in the low risk groups; 47% and 26%, in the intermediate risk groups and 25% and 2%, in the high risk groups (log-rank=69.2 and 41.3, respectively; p<0.0001). According to ILI index the 10-year OS and PFS were 60% and 34%, respectively, in the low risk groups; 59% and 30%, in the intermediate risk groups and 17% and 0%, in the high risk groups (log-rank=86.6 and 58.5, respectively; p<0.0001). INTERPRETATION AND CONCLUSIONS: Both the IPI and ILI index, are useful for classifying FL patients into different risk groups. Although it seems that the ILI index has a higher discriminating power among groups, significant differences were not observed in identifying FL patients with a poor outcome.

Aged↗

Fludarabine uptake mechanisms in B-cell chronic lymphocytic leukemia.

Nucleoside derivatives are currently used in the treatment of hematologic malignancies. Although intracellular events involved in the pharmacologic action of these compounds have been extensively studied, the role of plasma membrane transporters in nucleoside-derived drug bioavailability and action in leukemia cells has not been comprehensively addressed. We have monitored the amounts of mRNA for the 5 nucleoside transporter isoforms cloned so far (CNT1, CNT2, CNT3, ENT1, and ENT2) in several human cell types and in normal human leukocytes. We then examined the expression patterns of these plasma membrane proteins in patients with chronic lymphocytic leukemia (CLL) and correlated them with in vitro fludarabine cytotoxicity. Despite a huge individual variability in the mRNA amounts for every transporter gene expressed in CLL cells (CNT2, CNT3, ENT1, and ENT2), no relationship between mRNA levels and in vitro fludarabine cytotoxicity was observed. Fludarabine accumulation in CLL cells was mostly, if not exclusively, mediated by ENT-type transporters whose biologic activity was clearly correlated with fludarabine cytotoxicity, which reveals a role of ENT-mediated uptake in drug responsiveness in patients with CLL.

Adaptor Proteins, Signal Transducing↗

Spontaneous and drug-induced apoptosis is mediated by conformational changes of Bax and Bak in B-cell chronic lymphocytic leukemia.

The role of Bax and Bak, 2 proapoptotic proteins of the Bcl-2 family, was analyzed in primary B-cell chronic lymphocytic leukemia (CLL) cells following in vitro treatment with fludarabine, dexamethasone, or the combination of fludarabine with cyclophosphamide and mitoxantrone (FCM). A strong correlation was found between the number of apoptotic cells and the percentage of cells stained with antibodies recognizing conformational changes of Bax (n = 33; r = 0.836; P <.001) or Bak (n = 10; r = 0.948; P <.001). Preincubation of CLL cells with Z-VAD.fmk (N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone), a broad caspase inhibitor, abolished caspase-3 activation, exposure of phosphatidylserine residues, and reactive oxygen species generation; partially reversed the loss of transmembrane mitochondrial potential (DeltaPsim); but did not affect Bax or Bak conformational changes. These results indicate that the conformational changes of Bax and Bak occur upstream of caspase activation or are caspase independent. Following drug-induced apoptosis, Bax integrates into mitochondria, as demonstrated by fluorescence microscopy and Western blot, without changes in the total amount of Bax or Bak protein. Fludarabine and FCM induce p53 stabilization, but do not seem to be essential in inducing Bax and Bak conformational changes, as they are also observed in dexamethasone-treated CLL cells. These results demonstrate that, in CLL cells, the change in the intracellular localization of Bax from cytosol to mitochondria and the conformational changes of Bax and Bak are among the early steps in the induction of cell death.

Aged↗

Clinical impact of the differentiation profile assessed by immunophenotyping in patients with diffuse large B-cell lymphoma.

To analyze the relationship between immunophenotyping profile and main clinicopathological features and outcome in diffuse large B-cell lymphoma (DLBCL), we studied 128 patients (59 men, 69 women; median age 65 years) consecutively diagnosed with de novo DLBCL in a single institution. Cells from each patient were immunostained with CD20, CD79a, CD5, CD10, bcl-6, MUM1, CD138, bcl-2, p53, p27, and Ki-67 antibodies. Four immunophenotyping profiles were distinguished according to the pattern of differentiation: germinal center-CD10(+) (GC-CD10(+); CD10(+)/Bcl-6(+)/MUM1(-)/CD138(-)), germinal center-CD10(-) (GC-CD10(-); CD10(-)/Bcl-6(+)/ MUM1(-)/CD138(-)), post-germinal center (pGC; CD10(-)/bcl-6(+/-)/ MUM1(+)/CD138(-)), and plasmablastic (CD10(-)/bcl-6(-)/MUM1(+)/CD138(+)). Rearrangement of bcl-2 was studied by polymerase chain reaction (PCR) in 57 patients. Single-antigen expression was as follows: CD5, 2%; CD10, 21%; bcl-6, 72%; MUM1, 54%; CD138, 2%; bcl-2, 59%; p53, 28%; p27, 40%. Distribution according to differentiation profiles was as follows: GC-CD10(+), 24 patients, GC-CD10-, 30 patients; pGC, 60 patients; plasmablastic, 2 patients; other patterns, 12 patients. The pGC profile was associated with primary nodal presentation and immunoblastic morphology, whereas GC-CD10(+) tumors showed disseminated disease, centroblastic morphology, bcl-2 rearrangement, and lower Ki-67 proliferative index. GC-CD10(-) patients more often presented with primary extranodal origin, early stage, normal lactic acid dehydrogenase (LDH) levels, and low or low/intermediate International Prognostic Index (IPI) scores than the others. However, no significant difference was found in terms of response or overall survival (OS) according to these profiles. Expression of bcl-2 was associated with advanced stage, high or high-intermediate IPI, and poor OS. Expression of bcl-2 maintained predictive value in multivariate analysis, with stage and LDH. In conclusion, differentiation profile was associated with particular clinicopathological features but was not essential to predicting outcome in DLBCL patients.

Adult↗

Risk factors for acute graft-versus-host disease in patients undergoing transplantation with CD34+ selected blood cells from HLA-identical siblings.

A study on 315 patients undergoing transplantation with CD34+ selected blood cells from HLA-identical siblings was performed to determine risk factors for acute GVHD (aGVHD). Recipients of a dose of CD34+ cells (x 10(6)/kg) of 2 or less, more than 2 to 4, and more than 4 had a cumulative incidence of aGVHD grades I-IV of 21%, 35%, and 43%, respectively (log-rank P =.01); similarly, recipients of a dose of CD3+ cells (x 10(6)/kg) of 0.05 or less, more than 0.05 to 0.1, and more than 0.1 had a cumulative incidence of aGVHD grades I-IV of 18%, 35%, and 44%, respectively (log-rank P =.007). Using a Cox regression model, 4 independent factors for aGVHD I-IV were identified: increased CD34+ cell dose (P =.02), increased CD3+ cell dose (P =.02), female patients (P =.01), and higher patient age (> 42 years) (P =.007). This study shows, for the first time in T-cell-depleted transplantations, a positive correlation between the number of CD34+ cells and aGVHD and, also, that the number of CD3+ cells necessary to initiate aGVHD is lower than previously reported.

Acute Disease↗

ATM gene inactivation in mantle cell lymphoma mainly occurs by truncating mutations and missense mutations involving the phosphatidylinositol-3 kinase domain and is associated with increasing numbers of chromosomal imbalances.

The ataxia-telangiectasia mutated (ATM) gene codifies for a protein critically involved in the cellular response to DNA damage. ATM alterations have been observed in some sporadic lymphoproliferative disorders. The recurrent 11q22-23 deletions found in mantle cell lymphoma (MCL) suggest that ATM could be inactivated in these lymphomas. In this study, ATM gene alterations and protein expression were examined in 20 and 17 MCL tumor specimens, respectively. Previously, these patients had been examined for p53 and p14(ARF) gene status and analyzed by comparative genomic hybridization. Nine patients had 11q22-23 losses. Eight ATM gene mutations were detected in 7 patients. These alterations were 3 missense mutations in the phosphatidylinositol-3 kinase (PI-3K) domain and 5 truncating mutations, including 3 frameshifts, a nonsense mutation, and a substitution of the initial methionine. All truncating mutations were associated with lack of protein expression. Somatic origin was demonstrated in 3 mutations, whereas one mutation was carried heterozygously in the patient germ line. Chromosomal imbalances were significantly higher in typical MCL with ATM inactivation (7.8 +/- 1.3) than in tumors with the wild-type gene (3 +/- 1.1) (P =.001). Moreover, tumors with bi-allelic ATM alteration were associated with 3q gains (P =.015) and frequent extranodal involvement (P =.049). ATM gene alterations were not related to the histologic variant of the tumors, p53/p14(ARF) gene status, survival, or other clinicopathologic features of the patients. These findings indicate that ATM gene mutations in MCL are mainly truncating or missense mutations involving the PI-3K domain, and that may play a role in the pathogenesis of a subset of these tumors with increased numbers of chromosomal imbalances.

Alleles↗

Genetic imbalances in progressed B-cell chronic lymphocytic leukemia and transformed large-cell lymphoma (Richter's syndrome).

Chromosomal imbalances were examined by comparative genomic hybridization in 30 cases of B-cell chronic lymphocytic leukemia (CLL) at diagnosis, in sequential samples from 17 of these patients, and in 6 large B-cell lymphomas transformed from CLL [Richter's syndrome (RS)] with no available previous sample. The most common imbalances in CLL at diagnosis were gains in chromosome 12 (30%), and losses in chromosomes 13 (17%), 17p (17%), 8p (7%), 11q (7%), and 14q (7%). The analysis of sequential samples showed an increased number of chromosomal imbalances in 6 of 10 (60%) patients with clinical progression and in 2 patients with stable stage C disease. No karyotypic evolution was observed in four cases with stable stage A disease and in one RS clonally unrelated to the previous CLL. Gains of 2pter, and 7pter, and losses of 8p, 11q, and 17p were recurrent alterations associated with karyotype progression. RS showed a higher number of gains, losses, total alterations, and losses of 8p and chromosome 9 than CLL at diagnosis. 17p losses were associated with p53 gene mutations and with a significantly higher number of chromosomal imbalances than tumors with normal chromosome 17 profile. However, no relationship was observed between 9p deletions and p16(INK4a) gene alterations. Losses of 17p and an increased number of losses at diagnosis were significantly associated with a shorter survival. These findings indicate that CLL has frequent chromosomal imbalances, which may increase during the progression of the disease and transformation into large cell lymphoma. Genetic alterations detected by comparative genomic hybridization may also be of prognostic significance.

Chromosome Aberrations↗

CD34+-enriched-CD19+-depleted autologous peripheral blood stem cell transplantation for chronic lymphoproliferative disorders: high purging efficiency but increased risk of severe infections.

OBJECTIVE: The main objective of this work was to decrease the incidence of relapse after autologous stem cell transplantation with a "double purging" procedure. METHODS: We used a "positive" (CD34) and "negative" (CD19) double selection method to improve the efficacy of "single purging" of hematopoietic harvests in poor-prognosis lymphoproliferative disorders. All patients included in the study had a positive molecular marker of their disease. Minimal residual disease (MRD) was studied by flow cytometry and PCR techniques during the purging procedure and after transplantation. RESULTS: Twenty-six patients fulfilled entry criteria. Median age of patients was 50 years (range: 33-66); 17 were male and 9 female. Thirteen (50%) of the patients mobilized an adequate number of CD34+ cells (>or=3 x 10(6)/kg) to proceed with the double-selection protocol. Twelve of the 13 harvests became PCR negative after purging. Ten patients were grafted with the selected products and all but one engrafted without delay. After a median follow-up of 30 months, 2 of 10 patients suffered a molecular relapse at 7 and 19 months respectively. The earlier relapse was observed in the patient who received a MRD+ product. Only one patient experienced a clinical relapse. Three patients died due to obliterans bronchiolitis, pneumococcal sepsis, and septic shock of unknown origin, respectively, and three others presented life-threatening infections. CONCLUSION: Therefore, CD34+/CD19+ positive/negative selection is an effective purging approach in patients with chronic lymphoproliferative disorders. This favorable effect is, however, counterbalanced by the high frequency of life-threatening infections.

Adult↗