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1.
Ann Oncol ; 22(2): 468-71, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20624787

RESUMEN

BACKGROUND: Children with recurrent or refractory malignant lymphoma generally have a poor prognosis. There is a need for new active drug combinations for this high-risk group of patients. PATIENTS AND METHODS: This study evaluated the activity and toxicity of the methotrexate, ifosfamide, etoposide and dexamethasone (MIED) regimen for childhood refractory/recurrent non-Hodgkin's lymphoma (NHL) or Hodgkin's lymphoma (HL). From 1991 through 2006, 62 children with refractory/recurrent NHL (n = 24) or HL (n = 38) received one to six cycles of MIED. Based on MIED response, intensification with hematopoietic stem cell transplantation (HSCT) was considered. RESULTS: There were 10 complete (CR) and 5 partial responses (PR) among the 24 children with NHL [combined response rate, 63%; 95% confidence interval (CI) 38% to 73%]. There were 13 CR and 18 PR among the 37 assessable children with HL (combined response rate, 84%; 95% CI, 68% to 94%). Although 59% courses were associated with grade IV neutropenia, treatment was well tolerated and without toxic deaths. CONCLUSIONS: MIED is an effective regimen for refractory/recurrent childhood malignant lymphoma, permitting a bridge to intensification therapy with HSCT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Dexametasona/administración & dosificación , Etopósido/administración & dosificación , Enfermedad de Hodgkin/patología , Humanos , Ifosfamida/administración & dosificación , Linfoma no Hodgkin/patología , Metotrexato/administración & dosificación , Recurrencia , Terapia Recuperativa
2.
Leukemia ; 23(6): 1127-30, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19194463

RESUMEN

There has been a steady improvement in cure rates for children with advanced-stage lymphoblastic non-Hodgkin's lymphoma. To further improve cure rates whereas minimizing long-term toxicity, we designed a protocol (NHL13) based on a regimen for childhood T-cell acute lymphoblastic leukemia, which features intensive intrathecal chemotherapy for central -nervous system-directed therapy and excludes prophylactic cranial irradiation. From 1992 to 2002, 41 patients with advanced-stage lymphoblastic lymphoma were enrolled on the protocol. Thirty patients had stage III and 11 had stage IV disease. Thirty-three cases had a precursor T-cell immunophenotype, five had precursor B-cell immunophenotype and in three immunophenotype was not determined. Out of the 41 patients, 39 (95%) achieved a complete remission. The 5-year event-free rate was 82.9+/-6.3% (s.e.), and 5-year overall survival rate was 90.2+/-4.8% (median follow-up 9.3 years (range 4.62-13.49 years)). Adverse events included two induction failures, one death from typhlitis during remission, three relapses and one secondary acute myeloid leukemia. The treatment described here produces high cure rates in children with lymphoblastic lymphoma without the use of prophylactic cranial irradiation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Asparaginasa/administración & dosificación , Linfocitos B/patología , Niño , Preescolar , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Daunorrubicina/administración & dosificación , Dexametasona/administración & dosificación , Supervivencia sin Enfermedad , Etopósido/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Espinales , Masculino , Mercaptopurina/administración & dosificación , Metotrexato/administración & dosificación , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Prednisona/administración & dosificación , Inducción de Remisión/métodos , Linfocitos T/patología , Resultado del Tratamiento , Vincristina/administración & dosificación
3.
Leukemia ; 23(7): 1278-87, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19212329

RESUMEN

Inhibitory NK cell receptors are recognized as important determinants of NK cell activity in hematopoietic cell transplantation (HCT). The role of activating receptors and their acquisition after HCT is less certain. Therefore, we comprehensively evaluated both inhibitory and activating receptors in 59 patients receiving unrelated donor HCT. NK cell numbers normalized quickly relative to B and T cells; however, the expression of both inhibitory and activating isoforms of killer immunoglobulin-like receptors (KIRs) was delayed. Most NK cells expressed an immature phenotype during the first 6 months post-HCT; however, we found high expression of activating NKp46 and NKp44 natural cytotoxicity receptors (NCRs), and cytotoxicity was preserved. Early reconstituting NK cells from unmanipulated grafts showed lower cytotoxicity than those from T-cell-depleted grafts. Differences in NK cell reconstitution had significant effects on clinical outcomes. Patients whose NK cells reconstituted earlier had better survival and lower relapse rates. The best survival group was recipients who possessed HLA-C2 but their donor lacked the cognate-activating KIR2DS1. Collectively, our data underscore the clinical relevance of reconstituting NK cells and their activating KIRs and NCRs. In addition to NK cell quantification and genotyping, comprehensive assessment of NK cell functions and phenotypes, including activating receptors, is essential.


Asunto(s)
Neoplasias Hematológicas/cirugía , Trasplante de Células Madre Hematopoyéticas , Células Asesinas Naturales/inmunología , Receptores de Células Asesinas Naturales/metabolismo , Adolescente , Adulto , Secuencia de Bases , Niño , Preescolar , Cartilla de ADN , Femenino , Neoplasias Hematológicas/inmunología , Humanos , Lactante , Subgrupos Linfocitarios , Masculino , Acondicionamiento Pretrasplante , Resultado del Tratamiento , Adulto Joven
4.
Pediatr Blood Cancer ; 48(3): 349-53, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16302216

RESUMEN

A 21-year-old white male with relapsed acute lymphoblastic leukemia (ALL) developed an invasive Zygomycosis infection 3 weeks after beginning re-induction chemotherapy. Because of the high risk of fatal recurrence of the fungal infection, neither long-term maintenance chemotherapy nor allogeneic hematopoietic stem cell transplant (HSCT) was considered appropriate. Because his ALL blasts expressed CD34 but lacked CD133, he received a CD133 selected autologous graft following high-dose consolidation chemotherapy. The patient survives in remission 19 months after HSCT.


Asunto(s)
Antígenos CD/análisis , Glicoproteínas/análisis , Péptidos/análisis , Trasplante de Células Madre de Sangre Periférica , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirugía , Terapia Recuperativa , Antígeno AC133 , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Asparaginasa/administración & dosificación , Caspofungina , Niño , Terapia Combinada , Contraindicaciones , Dexametasona/administración & dosificación , Quimioterapia Combinada , Equinocandinas , Humanos , Separación Inmunomagnética , Lipopéptidos , Masculino , Mercaptopurina/administración & dosificación , Metotrexato/administración & dosificación , Péptidos Cíclicos/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Pirimidinas/uso terapéutico , Recurrencia , Inducción de Remisión , Trasplante Autólogo , Trasplante Homólogo , Triazoles/uso terapéutico , Vincristina/administración & dosificación , Voriconazol , Cigomicosis/complicaciones , Cigomicosis/tratamiento farmacológico
5.
Leukemia ; 18(10): 1581-6, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15356657

RESUMEN

We evaluated the clinical response to low-dose etoposide in relapsed acute lymphoblastic leukemia (ALL). Of the 45 patients with ALL in first bone marrow relapse enrolled on the ALL R15 protocol, 44 had received epipodophyllotoxins during frontline therapy. In the first week of remission induction therapy, patients received etoposide (50 mg/m(2) per day) administered orally as a single agent once or twice daily. On Day 8, patients started to receive dexamethasone, vincristine, and L-asparaginase. Etoposide was administered until Day 22. Two courses of consolidation therapy were followed by continuation therapy or hematopoietic stem cell transplantation. After 7 days of single-agent etoposide treatment, peripheral blast cell counts (P=0.013) and percentages of bone marrow blasts (P=0.016) were significantly reduced. In all, 38 (84.4%) attained second remission. Only time to relapse was significantly associated with outcome (P=0.025): the 5-year event-free survival estimates (+/-se) were 52.0+/-9.6% for those with late relapse and 20.0+/-8.0% for those with early relapse. We conclude that low-dose etoposide administered orally has a cytoreductive effect in relapsed ALL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/efectos de los fármacos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Asparaginasa/administración & dosificación , Médula Ósea/patología , Niño , Preescolar , Dexametasona/administración & dosificación , Etopósido/administración & dosificación , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Lactante , Masculino , Podofilotoxina/uso terapéutico , Inducción de Remisión , Resultado del Tratamiento , Vincristina/administración & dosificación
7.
Leukemia ; 16(10): 2072-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12357359

RESUMEN

To elucidate the clinical and biological features of childhood acute myeloid leukemia (AML) with the t(8;21), we reviewed the records of patients with AML treated at St Jude Children's Research Hospital over a 17-year period (1980 to 1996). Of 298 patients with AML, 40 (13%) had blast cells that contained the t(8;21). This translocation was associated with a high frequency of French-American-British M2 morphology (82%) and the presence of granulocytic sarcoma (23%). Molecular analysis detected the AML1-ETO fusion transcript in all 25 cases with the t(8;21) tested, but failed to identify additional cases with AML1-ETO among the 127 cases with other cytogenetic findings. Compared to patients with other genetic abnormalities, those with the t(8;21) were less likely to have internal tandem duplications of the FLT3 gene (none of 10 vs 16 of 68). The 6-year overall survival estimate was 55% +/- 9% and the event-free survival estimate, 33% +/- 7%. Of the clinical and biological features examined, only gender was prognostically significant: the 6-year overall survival estimate for males was 68% +/- 10%, compared to 33% +/- 11 for female patients (P = 0.03). Treatment outcome was not influenced by the chemotherapy regimen used or by the use of autologous hematopoietic stem cell transplantation. These results suggest that t(8;21)-positive AML represents a heterogeneous disease with variable outcome. The reported favorable outcome for t(8;21)-positive AML in other studies may be due to the use of high-dose cytarabine.


Asunto(s)
Cromosomas Humanos Par 21 , Cromosomas Humanos Par 8 , Leucemia Mieloide/genética , Translocación Genética , Enfermedad Aguda , Adolescente , Adulto , Niño , Preescolar , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Cariotipificación , Leucemia Mieloide/fisiopatología , Leucemia Mieloide/terapia , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia
8.
Leukemia ; 16(7): 1344-52, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12094259

RESUMEN

Clotrimazole is an antimycotic imidazole derivative that interferes with cellular Ca(2+) homeostasis. We investigated the effects of clotrimazole on acute lymphoblastic leukemia (ALL) cells. Treatment with 10 microM clotrimazole (a concentration achievable in vivo) reduced cell recovery from cultures of all nine ALL cell lines studied (B-lineage: OP-1, SUP-B15, RS4;11, NALM6, REH, and 380; T-lineage: MOLT4, CCRF-CEM, and CEM-C7). After 4 days of culture, median cell recovery was 10% (range, <1% to 37%) of cell recovery in parallel untreated cultures. Clotrimazole also inhibited recovery of primary ALL cells cultured on stromal feeder layers. After leukemic cells from 16 cases of ALL were cultured for 7 days with 10 microM clotrimazole, median cell recovery was <1% (range, <1% to 16%) of that in parallel untreated cultures. Clotrimazole was active against leukemic cells with genetic abnormalities associated with poor response to therapy and against multidrug-resistant cell lines. In contrast, mature T lymphocytes and bone marrow stromal cells were not affected. Clotrimazole induced depletion of intracellular Ca(2+) stores in ALL cells, which was followed by apoptosis, as shown by annexin V binding and DNA fragmentation. Thus, clotrimazole is cytotoxic to ALL cells at concentrations achievable in vivo.


Asunto(s)
Antifúngicos/farmacología , Apoptosis/efectos de los fármacos , Calcio/metabolismo , Clotrimazol/farmacología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Anexina A5/metabolismo , Niño , Preescolar , Fragmentación del ADN/efectos de los fármacos , Humanos , Lactante , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Linfocitos/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Células Tumorales Cultivadas
9.
Cancer ; 92(9): 2237-46, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11745277

RESUMEN

BACKGROUND: Lactic acidosis (LA) associated with hematologic malignancies is rare, ominous, and generally occurs in adults. Its pathogenesis is poorly understood. METHODS: The authors present one case of childhood lymphoma and two cases of childhood leukemia associated with LA, and they review the available literature. Plasma concentrations of insulin-like growth factors (IGFs), IGF binding proteins (IGFBPs), and tumor necrosis factor (TNF)-alpha were retrospectively measured to elucidate the pathogenesis of LA. RESULTS: Lactic acidosis has been reported to date in 28 cases of lymphoma and 25 cases of leukemia, including the authors' cases. Ongoing rapid cellular proliferation was indicated in all leukemia cases. The liver was involved in 43 of the 53 cases, and hypoglycemia was present in 20. The acidosis improved only if the disease responded to chemotherapy. Remission was achieved in only five of the reported cases. In the authors' three cases, LA was associated with altered concentrations of IGFs, IGFBPs, and TNF-alpha, although causality was not established. CONCLUSIONS: Lactic acidosis in association with hematologic malignancies carries an extremely poor prognosis. Because cancer cells have a high rate of glycolysis and produce a large quantity of lactate, this condition may result from an imbalance between lactate production and hepatic lactate utilization. The authors speculate that the IGF system is involved in the pathophysiology of LA in these patients. Only chemotherapy so far has been effective in correcting the acute acidosis in a few patients; however, it has not necessarily improved ultimate outcome.


Asunto(s)
Acidosis Láctica/etiología , Leucemia-Linfoma de Células T del Adulto/complicaciones , Leucemia/complicaciones , Linfoma/complicaciones , Acidosis Láctica/patología , Adolescente , Niño , Femenino , Glucólisis , Humanos , Masculino , Pronóstico , Estudios Retrospectivos , Somatomedinas/farmacología
10.
Proc Natl Acad Sci U S A ; 98(18): 10338-43, 2001 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-11526240

RESUMEN

Therapy-related acute myeloid leukemias (t-AML) with translocations of the MLL gene are associated with the use of topoisomerase II inhibitors. We established the emergence of the malignant clone in a child who developed t-AML with a t(11;19) (q23;p13.3) during treatment for acute lymphoblastic leukemia (ALL). The MLL-ENL and the reciprocal ENL-MLL genomic fusions and their chimeric transcripts were characterized from samples collected at the time of t-AML diagnosis. We used PCR with patient-specific genomic primers to establish the emergence of the MLL-ENL fusion in serially obtained DNA samples. The MLL-ENL fusion was not detectable in bone marrow at the time of ALL diagnosis or after 2 months of chemotherapy (frequency <8.3 x 10(-7) cells(-1)). The genomic fusion was first detected in bone marrow after 6 months of treatment at a frequency of one in 4,000 mononuclear bone marrow cells; the frequency was one in 70 cells after 20 months of therapy. At the first detection of MLL-ENL, the only topoisomerase II inhibitors the patient had received were one dose of daunorubicin and two doses of etoposide. The MLL-ENL fusion was not detectable in blood at the time of ALL diagnosis or after 0.7, 2, 8, 10, and 12 months of therapy but was detectable in blood at 16 months (one in 2.3 x 10(4) cells). Recombinogenic Alu sequences bracketed the breakpoints in both fusions. These data indicate that the malignant clone was not present before therapy, arose early during chemotherapy, and was able to proliferate even during exposure to antileukemic therapy.


Asunto(s)
Linfoma de Burkitt/tratamiento farmacológico , Leucemia Mieloide Aguda/etiología , Neoplasias Primarias Secundarias/etiología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Secuencia de Bases , Linfoma de Burkitt/genética , Cartilla de ADN/genética , ADN de Neoplasias/genética , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Modelos Genéticos , Datos de Secuencia Molecular , Proteína de la Leucemia Mieloide-Linfoide , Neoplasias Primarias Secundarias/genética , Proteínas de Fusión Oncogénica/genética , Inhibidores de Topoisomerasa II , Translocación Genética
11.
Leukemia ; 15(9): 1326-30, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11516092

RESUMEN

To identify treatment factors that may affect the survival of children with inv(16)(p13.1q22), we compared the outcomes of 19 patients with this genetic feature treated at our institution during two treatment eras. Nine patients were treated during era 1 (1980 to 1987), and 10 were treated during era 2 (1988 to 1996). All entered complete remission (CR) with induction therapy. Eight of the nine children treated in era 1 died, seven of relapsed leukemia. In contrast, three of 10 patients treated during era 2 have died, all of non-disease-related causes. Event-free survival (EFS) estimates were significantly higher for patients treated during era 2 than for those treated during era 1 (P = 0.03); the 6-year estimates were 70 +/- 15% (s.e.) and 11 +/- 7%, respectively. Era 2 treatment protocols differed from those of era 1 in their use of higher doses of cytarabine and etoposide during induction and consolidation chemotherapy and in their use of 2-chlorodeoxyadenosine (2-CDA). These results suggest that dose intensification of cytarabine benefits children with AML and inv(16), as is the case in adults. They also suggest that dose intensification of etoposide and addition of 2-CDA may also offer an advantage. This study underscores the dependence of the prognostic impact of cytogenetic features on the efficacy of treatment.


Asunto(s)
Leucemia Mieloide/terapia , Enfermedad Aguda , Adolescente , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Trasplante de Médula Ósea , Niño , Preescolar , Inversión Cromosómica , Cromosomas Humanos Par 16 , Cladribina/uso terapéutico , Terapia Combinada , Citarabina/administración & dosificación , Citarabina/uso terapéutico , Quimioterapia Combinada , Etopósido/administración & dosificación , Etopósido/uso terapéutico , Femenino , Humanos , Lactante , Leucemia Megacarioblástica Aguda/genética , Leucemia Megacarioblástica Aguda/terapia , Leucemia Monocítica Aguda/genética , Leucemia Monocítica Aguda/terapia , Leucemia Mieloide/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mielomonocítica Aguda/genética , Leucemia Mielomonocítica Aguda/terapia , Masculino , Pronóstico , Resultado del Tratamiento
12.
Blood ; 97(12): 3727-32, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11389009

RESUMEN

To describe the clinical and biologic features of pediatric acute megakaryoblastic leukemia (AMKL) and to identify prognostic factors, experience at St Jude Children's Research Hospital was reviewed. Of 281 patients with acute myeloid leukemia treated over a 14-year period, 41 (14.6%) had a diagnosis of AMKL. Six patients had Down syndrome and AMKL, 6 had secondary AMKL, and 29 had de novo AMKL. The median age of the 22 boys and 19 girls was 23.9 months (range, 6.7-208.9 months). The rate of remission induction was 60.5%, with a 48% rate of subsequent relapse. Patients with Down syndrome had a significantly higher 2-year event-free survival (EFS) estimate (83%) than did other patients with de novo AMKL (14%) or with secondary AMKL (20%; P < or =.038). Among patients who had de novo AMKL without Down syndrome, 2-year EFS was significantly higher after allogeneic bone marrow transplantation (26%) than after chemotherapy alone (0%; P =.019) and significantly higher when performed during remission (46%) than when performed during persistent disease (0%; P =.019). The 5-year survival estimates were significantly lower for de novo AMKL (10%) than for other forms of de novo AML (42%; P <.001). Treatment outcome is very poor for patients with AMKL in the absence of Down syndrome. Remission induction is the most important prognostic factor. Allogeneic transplantation during remission offers the best chance of cure; in the absence of remission, transplantation offers no advantage over chemotherapy alone. (Blood. 2001;97:3727-3732)


Asunto(s)
Leucemia Megacarioblástica Aguda/diagnóstico , Trasplante de Médula Ósea , Supervivencia sin Enfermedad , Síndrome de Down/complicaciones , Femenino , Humanos , Leucemia Megacarioblástica Aguda/etiología , Leucemia Megacarioblástica Aguda/mortalidad , Masculino , Neoplasias Primarias Secundarias , Pronóstico , Estudios Prospectivos , Inducción de Remisión , Estudios Retrospectivos , Tasa de Supervivencia , Trasplante Homólogo , Resultado del Tratamiento
13.
J Clin Oncol ; 19(11): 2804-11, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11387351

RESUMEN

PURPOSE: To develop more effective chemotherapy regimens for childhood acute myelogenous leukemia (AML). PATIENTS AND METHODS: Between June 1991 and December 1996, we administered the nucleoside analog 2-chlorodeoxyadenosine (2-CDA) to 73 children with primary AML and 20 children with secondary AML or myelodysplastic syndrome (MDS). Patients received one or two 5-day courses of 2-CDA (8.9 mg/m(2)/d) given by continuous infusion. All patients then received one to three courses of daunomycin, cytarabine, and etoposide (DAV) remission induction therapy. RESULTS: Seventy-two patients with primary AML were assessable for response. Their rate of complete remission (CR) was 24% after one course of 2-CDA, 40% after two courses of 2-CDA, and 78% after DAV therapy. Of the 57 patients who entered CR, 11 subsequently underwent allogeneic bone marrow transplantation (BMT), and 40 underwent autologous BMT. Twenty-nine patients remain in continuous CR after BMT. Two patients remain in CR after chemotherapy only. The 5-year event-free survival (EFS) estimate was 40% (SE = 0.080%). Patients with French-American-British (FAB) M5 AML had a higher rate of CR after treatment with 2-CDA (45% after one course and 70.6% after two courses) than did others (P =.002). In contrast, no patient with FAB M7 AML (n = 10) entered CR after treatment with 2-CDA. Similarly, no patient with primary MDS (n = 6) responded to 2-CDA. Seven patients with secondary AML or MDS (n = 14) had a partial response to one course of 2-CDA. CONCLUSION: This agent was well tolerated, and its toxicity was acceptable. Future trials should examine the effectiveness of 2-CDA given in combination with other agents effective against AML.


Asunto(s)
Antineoplásicos/farmacología , Cladribina/farmacología , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Adolescente , Antineoplásicos/administración & dosificación , Trasplante de Médula Ósea , Niño , Preescolar , Cladribina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Recién Nacido , Infusiones Intravenosas , Masculino , Resultado del Tratamiento
14.
Leukemia ; 15(1): 166-70, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11243385

RESUMEN

Hematologic relapse remains the greatest obstacle to the cure of children with acute lymphoblastic leukemia (ALL). Recent studies have shown that patients with increased risk of relapse can be identified by measuring residual leukemic cells, called minimal residual disease (MRD), during clinical remission. Current PCR methods, however, for measuring MRD are cumbersome and time-consuming. To improve and simplify MRD assessment, we developed a real-time quantitative PCR (RQ-PCR) assay for detection of leukemic cells that harbor the TAL-1 deletion. We studied serial dilutions of leukemic DNA and found the assay had a sensitivity of detection of one leukemic cell among 100,000 normal cells. We then investigated 23 samples from eight children with ALL in clinical remission. We quantified residual leukemic cells by using the TAL-1 RQ-PCR assay and by using limiting dilution analysis. In 17 samples, both methods detected MRD levels > or =0.001%. The percentages of leukemic cells measured by the two methods correlated well (r2 = 0.926). In the remaining six samples, both methods detected fewer than 0.001% leukemic cells. We conclude the TAL-1 RQ-PCR assay can be used for rapid, sensitive and accurate assessment of MRD in T-lineage ALL with the TAL-1 deletion.


Asunto(s)
Proteínas de Unión al ADN/genética , Neoplasia Residual/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Proteínas Proto-Oncogénicas , Factores de Transcripción , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Linaje de la Célula , Proteínas de Unión al ADN/análisis , Eliminación de Gen , Humanos , Neoplasia Residual/genética , Reacción en Cadena de la Polimerasa/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteína 1 de la Leucemia Linfocítica T Aguda , Linfocitos T/patología
15.
Blood ; 97(3): 752-8, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11157494

RESUMEN

Interleukin 4 (IL-4) suppresses the growth of acute lymphoblastic leukemia (ALL) cells, but its clinical usefulness is limited by proinflammatory activity due mainly to the interaction of cytokine with endothelial cells and fibroblasts. Stroma-supported cultures of leukemic lymphoblasts were used to test the antileukemic activity of an IL-4 variant, BAY 36-1677, in which the mutations Arg 121 to Glu and Thr 13 to Asp ensure high affinity for IL-4Ralpha/IL-2Rgamma receptors expressed by lymphoid cells, without activation of the IL-4Ralpha/IL-13Ralpha receptors mainly expressed by other cells. BAY 36-1677 (25 ng/mL) was cytotoxic in 14 of 16 cases of B-lineage ALL; the median reduction in cell recovery after 7 days of culture was 85% (range, 17%-95%) compared to results of parallel cultures not exposed to the cytokine. Twelve of the 14 sensitive cases had t(9;22) or 11q23 abnormalities; 3 were obtained at relapse. BAY 36-1677 induced apoptosis in leukemic lymphoblasts but did not substantially affect the growth of normal CD34+ cells, thus conferring a growth advantage to normal hematopoietic cells over leukemic lymphoblasts in vitro. BAY 36-1677 had antileukemic activity equal or superior to that produced by native IL-4, but it lacked any effects on the growth of endothelial cells and fibroblasts. The molecular manipulation of IL-4 to abrogate its proinflammatory activity has generated a novel and therapeutically promising cytokine for the treatment of high-risk ALL.


Asunto(s)
Apoptosis , Interleucina-4/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adolescente , División Celular/efectos de los fármacos , Células Cultivadas , Niño , Preescolar , Ensayos de Selección de Medicamentos Antitumorales , Endotelio/citología , Endotelio/efectos de los fármacos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Lactante , Interleucina-4/química , Interleucina-4/genética , Mutagénesis Sitio-Dirigida , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Estructura Secundaria de Proteína , Células del Estroma/fisiología , Células Tumorales Cultivadas
16.
J Pediatr Hematol Oncol ; 22(6): 495-501, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11132215

RESUMEN

PURPOSE: To improve outcome and study biology of childhood acute lymphoblastic leukemia (ALL) in El Salvador. PATIENTS AND METHODS: Between January 1994 and December 1996, 153 children of El Salvador had newly diagnosed ALL treated in a collaborative program between Hospital Benjamin Bloom and St. Jude Children's Research Hospital (SJCRH). Therapy was based on a modified SJCRH protocol, with uniform remission induction (prednisone, vincristine, L-asparaginase) followed-up by consolidation with teniposide/cytarabine and/or high-dose methotrexate. Continuation treatment was risk-stratified: 123 patients assigned to the high-risk group received weekly rotational drug pairs, and 16 assigned to the standard-risk group received daily 6-mercaptopurine, weekly methotrexate, and monthly pulses of vincristine plus dexamethasone. High risk was defined as: DNA index < 1.16, age 12 months or younger, white blood cell count > or = 50 x 10(9)/L, T-cell immunophenotype, anterior mediastinal mass, central nervous system leukemia at diagnosis, or t(4;11), t(1;19), or t(9;22). Duration of the continuation treatment was 2.5 years in both groups. The median age at diagnosis of all patients was 4.8 (range I d-17 yrs), median leukocyte count was 15 (range 1-766) x 10(9)/L, and sex distribution was equal. RESULTS: Immunophenotypes were early beta-progenitor in 79%, T-cell in 3.9%, and inconclusive in 17% of cases. DNA index was <1.16 in 80.5% and was > or = 1.16 in 19.5% of the 123 known cases. For the analyzes, patients who refused therapy (abandoned treatment) were considered to have treatment failure as of their last follow-up dates. Complete remission was achieved in 126 of 151 (82.4%) patients (11 abandoned therapy during induction). The overall 4-year event-free survival (EFS) rate +/- 1 standard error was 48 +/- 6%. The 4-year EFS rates in patients at high-risk and standard-risk were 46 +/- 7% (n = 121) and 69 +/- 15% (n = 16), respectively (P = 0.20). When patients who refused further treatment are censored, the corresponding 4-year estimates of EFS are 51 +/- 8% and 75 +/- 14%, respectively. CONCLUSIONS: These results suggest that the biology of childhood ALL in El Salvador appears to be similar to that seen in the United States. Risk-directed chemotherapy can successfully be used in developing countries, but risk factors must be carefully determined and applied.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Asparaginasa/administración & dosificación , Niño , Preescolar , Citarabina/administración & dosificación , Países en Desarrollo , Supervivencia sin Enfermedad , El Salvador , Femenino , Humanos , Lactante , Recién Nacido , Cooperación Internacional , Masculino , Metotrexato/administración & dosificación , Estadificación de Neoplasias , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Prednisona/administración & dosificación , Análisis de Supervivencia , Tenipósido/administración & dosificación , Factores de Tiempo , Estados Unidos , Vincristina/administración & dosificación
17.
Blood ; 96(10): 3529-36, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11071651

RESUMEN

Folate receptor (FR) type beta is expressed in the myelomonocytic lineage, predominantly during neutrophil maturation and in myeloid leukemias. FR-beta expression was elevated up to 20-fold by all-trans retinoic acid (ATRA) in KG-1 myeloid leukemia cells in a dose-dependent and reversible manner in the absence of terminal differentiation or cell growth inhibition. ATRA also increased FR-beta expression in vitro in myeloid leukemia cells from patient marrow. FR-beta was not up-regulated in KG-1 cells treated with phorbol ester, dexamethasone, 1,25-dihydroxy vitamin D(3), or transforming growth factor beta. ATRA did not induce FR-beta expression in receptor negative cells of diverse origin. The ATRA-induced increase in FR-beta expression in KG-1 cells occurred at the level of messenger RNA synthesis, and in 293 cells containing a stably integrated FR-beta promoter-luciferase reporter construct, ATRA induced expression of the reporter. From experiments using retinoid agonists and antagonists and from cotransfection studies using the FR-beta promoter and expression plasmids for the nuclear receptors retinoic acid receptor (RAR)alpha, RARbeta, or RARgamma, it appears that the retinoid effect on FR-beta expression could be mediated by ligand binding to RARs alpha, beta, or gamma, but not to retinoid X receptors. Furthermore, there was apparent cross-talk between RARalpha and RARgamma selective agonists or antagonists, suggesting a common downstream target for RAR isoforms in inducing FR-beta expression. Thus, blocks in the RARalpha-specific pathway of retinoid-induced differentiation may be bypassed during retinoid induction of FR-beta expression. The results suggest that to facilitate FR-targeted therapies, retinoids may be used to modulate FR-beta expression in myeloid leukemia cells refractory to retinoid differentiation therapy.


Asunto(s)
Proteínas Portadoras/efectos de los fármacos , Leucemia Mieloide/metabolismo , Receptores de Superficie Celular , Tretinoina/farmacología , Antineoplásicos/farmacología , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/patología , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , ADN Recombinante/efectos de los fármacos , Receptores de Folato Anclados a GPI , Regulación de la Expresión Génica/efectos de los fármacos , Glicosilfosfatidilinositoles/metabolismo , Humanos , Leucemia Mieloide/patología , Proteínas de Neoplasias/efectos de los fármacos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosfatidilinositol Diacilglicerol-Liasa , Regiones Promotoras Genéticas/efectos de los fármacos , Isoformas de Proteínas/efectos de los fármacos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Ácido Retinoico/fisiología , Transcripción Genética/efectos de los fármacos , Transfección , Tretinoina/análogos & derivados , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/metabolismo , Regulación hacia Arriba/efectos de los fármacos
18.
Leukemia ; 14(10): 1736-42, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11021748

RESUMEN

The purpose of this study was to assess the feasibility and efficacy of a treatment regimen for pediatric acute myelogenous leukemia (AML) that uses four rotating drug pairs and adjusts dosages of etoposide and cytarabine to target specific plasma concentrations. Thirty-one girls and 27 boys (median age, 9.7 years) with de novo AML were treated on the protocol. Six cycles of chemotherapy were planned. Cycles 1 to 4 comprised the drug combinations cytarabine plus etoposide, cytarabine plus daunomycin, etoposide plus amsacrine, and etoposide plus azacitidine, respectively. For cycles 5 and 6, the first two combinations were repeated. Dosages were adjusted to achieve plasma concentrations of 1.0 microM +/- 0.1 microM cytarabine and 30 microM +/- 0.3 microM etoposide. Forty-four patients (76%) entered complete remission. Of those, 24 have had relapses; 23 remain alive in first or subsequent remission. The 5-year event-free survival (EFS) estimate was 31.0% +/- 5.9%; the 5-year survival estimate was 41.4% +/- 6.3%. Six patients (10%) died of the toxic effects of therapy. Severe neutropenia occurred in all cycles. Long-term complications of therapy included hepatitis C, cardiac insufficiency, and hearing loss. Adjustment of cytarabine and etoposide dosage was feasible for achieving targeted plasma drug concentrations; however, the potential clinical efficacy of this approach was offset by substantial acute and long-term toxicity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Preescolar , Citarabina/administración & dosificación , Citarabina/farmacocinética , Relación Dosis-Respuesta a Droga , Etopósido/administración & dosificación , Etopósido/farmacocinética , Femenino , Humanos , Lactante , Masculino , Resultado del Tratamiento
19.
Blood ; 96(8): 2691-6, 2000 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11023499

RESUMEN

By using rapid flow cytometric techniques capable of detecting one leukemic cell in 10(4) normal cells, we prospectively studied minimal residual disease (MRD) in 195 children with newly diagnosed acute lymphoblastic leukemia (ALL) in clinical remission. Bone marrow aspirates (n = 629) were collected at the end of remission induction therapy and at 3 intervals thereafter. Detectable MRD (ie, > or = 0.01% leukemic mononuclear cells) at each time point was associated with a higher relapse rate (P < .001); patients with high levels of MRD at the end of the induction phase (> or = 1%) or at week 14 of continuation therapy (> or = 0.1%) had a particularly poor outcome. The predictive strength of MRD remained significant even after adjusting for adverse presenting features, excluding patients at very high or very low risk of relapse from the analysis, and considering levels of peripheral blood lymphoblasts at day 7 and day 10 of induction therapy. The incidence of relapse among patients with MRD at the end of the induction phase was 68% +/- 16% (SE) if they remained with MRD through week 14 of continuation therapy, compared with 7% +/- 7% if MRD became undetectable (P = .035). The persistence of MRD until week 32 was highly predictive of relapse (all 4 MRD(+) patients relapsed vs 2 of the 8 who converted to undetectable MRD status; P = .021). Sequential monitoring of MRD by the method described here provides highly significant, independent prognostic information in children with ALL. Recent improvements in this flow cytometric assay have made it applicable to more than 90% of all new patients. (Blood. 2000;96:2691-2696)


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Asparaginasa/administración & dosificación , Niño , Preescolar , Terapia Combinada , Irradiación Craneana , Citarabina/administración & dosificación , Daunorrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Citometría de Flujo , Humanos , Hidrocortisona/administración & dosificación , Inmunofenotipificación , Lactante , Masculino , Mercaptopurina/administración & dosificación , Metotrexato/administración & dosificación , Neoplasia Residual , Células Neoplásicas Circulantes , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Prednisona/administración & dosificación , Pronóstico , Estudios Prospectivos , Inducción de Remisión , Resultado del Tratamiento , Vincristina/administración & dosificación
20.
Leukemia ; 14(9): 1570-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10995002

RESUMEN

Between May 1987 and January 1991, 1354 patients, 1-21 years old, with standard or poor prognosis B-lineage acute lymphocytic leukemia were treated on the Pediatric Oncology Group Study 8602. One thousand three hundred and twenty-three patients entered remission and 1051 patients were randomized on day 43 to an intensification regimen containing L-asparaginase and intermediate-dose methotrexate (regimen B) or cytarabine and intermediate dose methotrexate (regimen C). After completion of intensification at week 25, all patients received the same maintenance therapy until 3 years from diagnosis. Overall 5-year continuous complete remission (CCR) for regimen B was 72+/-2% (s.e.) and for regimen C, 73+/-2% (P = 0.72 by log-rank analysis). Significant differences between treatments for CCR, testicular, CNS relapses overall or with regard to phenotype (pre-B vs early pre-B), gender, or race were not detected. During intensification, regimen C had significantly more bacterial infections (P = 0.05) and days spent in the hospital (P < 0.001) compared with regimen B, while regimen B had significantly more allergic reactions (P < 0.0001). No significant differences in CCR were noted between patients with pre-B and early pre-B ALL (P = 0.22 stratified by risk group and treatment). This study was unable to detect statistical difference between asparaginase (regimen B) and cytarabine (regimen C) during the intensification phase of therapy in children with B-lineage acute lymphocytic leukemia.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Burkitt/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Asparaginasa/administración & dosificación , Asparaginasa/efectos adversos , Niño , Preescolar , Citarabina/administración & dosificación , Citarabina/efectos adversos , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Humanos , Lactante , Masculino , Metotrexato/administración & dosificación , Metotrexato/efectos adversos , Resultado del Tratamiento
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