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1.
Blood Cancer J ; 6: e424, 2016 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-27176800

RESUMEN

The pharmacological therapy of non-promyelocytic acute myeloid leukemia (AML) has remained unchanged for over 40 years with an anthracycline-cytarabine combination forming the backbone of induction treatments. Nevertheless, the survival of younger patients has increased due to improved management of the toxicity of therapies including stem cell transplantation. Older patients and those with infirmity that precludes treatment-intensification have, however, not benefited from improvements in supportive care and continue to experience poor outcomes. An increased understanding of the genomic heterogeneity of AML raises the possibility of treatment-stratification to improve prognosis. Thus, efforts to identify agents with non-conventional anti-leukemic effects have paralleled those aiming to optimize leukemia cell-kill with conventional chemotherapy, resulting in a number of randomized controlled trials (RCT). In the last 18 months, RCTs investigating the effects of vosaroxin, azacitidine and gemtuzumab ozogamycin and daunorubicin dose have been reported with some studies indicating a statistically significant survival benefit with the investigational agent compared with standard therapy and potentially, a new era in AML therapeutics. Given the increasing costs of cancer care, a review of these studies, with particular attention to the magnitude of clinical benefit with the newer agents would be useful, especially for physicians treating patients in single-payer health systems.


Asunto(s)
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ensayos Clínicos como Asunto , Humanos , Leucemia Mieloide Aguda/etiología , Leucemia Mieloide Aguda/mortalidad , Terapia Molecular Dirigida , Resultado del Tratamiento
2.
Drug Res (Stuttg) ; 66(1): 46-50, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25894087

RESUMEN

The ester prodrugs of ketoprofen with various naturally available antioxidants; menthol, thymol, eugenol, guiacol, vanillin and sesamol have been synthesized by the dicyclohexyl carbodiimide (DCC) coupling method, purified and characterized by spectral data. Further, their, partition coefficients have been determined as well as, hydrolytic studies performed. The synthesized compounds are more lipophilic compared to the parent moieties and are stable in acidic environment, which is a prerequisite for their oral absorption. Under gastric as well as intestinal pH conditions these prodrugs showed variable susceptibility towards hydrolysis. The title compounds when evaluated for anti-inflammatory, analgesic activities and ulcerogenicity, showed improvement over the parent drug.


Asunto(s)
Cetoprofeno/química , Cetoprofeno/farmacología , Profármacos/química , Profármacos/farmacología , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Estabilidad de Medicamentos , Femenino , Absorción Gástrica/fisiología , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Masculino , Ratas , Úlcera Gástrica/tratamiento farmacológico
3.
Leukemia ; 29(7): 1502-13, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25721895

RESUMEN

A risk-adapted treatment strategy is mandatory for myelodysplastic syndromes (MDS). We refined the World Health Organization (WHO)-classification-based Prognostic Scoring System (WPSS) by determining the impact of the newer clinical and cytogenetic features, and we compared its prognostic power to that of the revised International Prognostic Scoring System (IPSS-R). A population of 5326 untreated MDS was considered. We analyzed single WPSS parameters and confirmed that the WHO classification and severe anemia provide important prognostic information in MDS. A strong correlation was found between the WPSS including the new cytogenetic risk stratification and WPSS adopting original criteria. We then compared WPSS with the IPSS-R prognostic system. A highly significant correlation was found between the WPSS and IPSS-R risk classifications. Discrepancies did occur among lower-risk patients in whom the number of dysplastic hematopoietic lineages as assessed by morphology did not reflect the severity of peripheral blood cytopenias and/or increased marrow blast count. Moreover, severe anemia has higher prognostic weight in the WPSS versus IPSS-R model. Overall, both systems well represent the prognostic risk of MDS patients defined by WHO morphologic criteria. This study provides relevant in formation for the implementation of risk-adapted strategies in MDS.


Asunto(s)
Síndromes Mielodisplásicos/clasificación , Síndromes Mielodisplásicos/diagnóstico , Organización Mundial de la Salud , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Análisis Citogenético , Femenino , Estudios de Seguimiento , Humanos , Cooperación Internacional , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/terapia , Estadificación de Neoplasias , Pronóstico , Proyectos de Investigación , Medición de Riesgo , Tasa de Supervivencia , Adulto Joven
4.
N Engl J Med ; 369(25): 2391-2405, 2013 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-24325359

RESUMEN

BACKGROUND: Somatic mutations in the Janus kinase 2 gene (JAK2) occur in many myeloproliferative neoplasms, but the molecular pathogenesis of myeloproliferative neoplasms with nonmutated JAK2 is obscure, and the diagnosis of these neoplasms remains a challenge. METHODS: We performed exome sequencing of samples obtained from 151 patients with myeloproliferative neoplasms. The mutation status of the gene encoding calreticulin (CALR) was assessed in an additional 1345 hematologic cancers, 1517 other cancers, and 550 controls. We established phylogenetic trees using hematopoietic colonies. We assessed calreticulin subcellular localization using immunofluorescence and flow cytometry. RESULTS: Exome sequencing identified 1498 mutations in 151 patients, with medians of 6.5, 6.5, and 13.0 mutations per patient in samples of polycythemia vera, essential thrombocythemia, and myelofibrosis, respectively. Somatic CALR mutations were found in 70 to 84% of samples of myeloproliferative neoplasms with nonmutated JAK2, in 8% of myelodysplasia samples, in occasional samples of other myeloid cancers, and in none of the other cancers. A total of 148 CALR mutations were identified with 19 distinct variants. Mutations were located in exon 9 and generated a +1 base-pair frameshift, which would result in a mutant protein with a novel C-terminal. Mutant calreticulin was observed in the endoplasmic reticulum without increased cell-surface or Golgi accumulation. Patients with myeloproliferative neoplasms carrying CALR mutations presented with higher platelet counts and lower hemoglobin levels than patients with mutated JAK2. Mutation of CALR was detected in hematopoietic stem and progenitor cells. Clonal analyses showed CALR mutations in the earliest phylogenetic node, a finding consistent with its role as an initiating mutation in some patients. CONCLUSIONS: Somatic mutations in the endoplasmic reticulum chaperone CALR were found in a majority of patients with myeloproliferative neoplasms with nonmutated JAK2. (Funded by the Kay Kendall Leukaemia Fund and others.).


Asunto(s)
Calreticulina/genética , Mutación , Síndromes Mielodisplásicos/genética , Mielofibrosis Primaria/genética , Trombocitemia Esencial/genética , Secuencia de Aminoácidos , Enfermedades de la Médula Ósea/genética , Calreticulina/análisis , Exones , Humanos , Janus Quinasa 2/genética , Leucemia Mieloide/genética , Datos de Secuencia Molecular , Neoplasias/genética , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
5.
Br J Cancer ; 109(9): 2434-44, 2013 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24091621

RESUMEN

BACKGROUND: Activation of wild-type p53 with the small molecule sirtuin inhibitor Tenovin-6 (Tnv-6) induces p53-dependent apoptosis in many malignant cells. In contrast, Tnv-6 reduces chronic lymphocytic leukaemia (CLL) cell viability with dysregulation of autophagy, without increasing p53-pathway activity. METHODS: Here, we have investigated whether a quiescent phenotype (unique to CLL) determines the Tnv-6 response, by comparing the effects of Tnv-6 on activated and proliferating CLL. We further studied if these responses are p53-dependent. RESULTS: Unlike quiescent cells, cell death in activated cultures treated with Tnv-6 was consistently associated with p53 upregulation. However, p53 acetylation remained unchanged, without caspase-3 cleavage or apoptosis on electron microscopy. Instead, cellular ultrastructure and protein profiles indicated autophagy inhibition, with reduced ubiquitin-proteasome activity. In specimens with mutant TP53 cultured with Tnv-6, changes in the autophagy-associated protein LC3 occurred independently of p53. Cells treated with Tnv-6 analogues lacking sirtuin inhibitory activity had attenuated LC3 lipidation compared with Tnv-6 (P0.01), suggesting that autophagy dysregulation occurs predominantly through an effect on sirtuins. CONCLUSION: These cell cycle and p53-independent anti-leukaemic mechanisms potentially offer novel therapeutic approaches to target leukaemia-sustaining cells in CLL, including in disease with p53-pathway dysfunction. Whether targets in addition to sirtuins contribute to autophagy dysregulation by Tnv-6, requires further investigation.


Asunto(s)
Autofagia/fisiología , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Proteína p53 Supresora de Tumor/metabolismo , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Apoptosis/genética , Autofagia/efectos de los fármacos , Autofagia/genética , Benzamidas/farmacología , Caspasa 3/genética , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Ciclo Celular/fisiología , Proliferación Celular/efectos de los fármacos , Humanos , Interleucina-2/farmacología , Leucemia Linfocítica Crónica de Células B/genética , Proteínas Asociadas a Microtúbulos/genética , Persona de Mediana Edad , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genética , Ubiquitina/genética , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética
6.
Leuk Res ; 37(5): 561-5, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23395505

RESUMEN

In this multicentre retrospective study we have studied the impact of T cell chimerism on the outcome of 133 patients undergoing an alemtuzumab based reduced intensity conditioning allograft (RIC). The median age of the patients was 50 years (range 42-55 years). 77 patients were transplanted using an HLA identical sibling donor while 56 patients received a fully matched volunteer unrelated donor graft. 64 patients had a lymphoid malignancy and 69 were transplanted for a myeloid malignancy. 38 patients (29%) relapsed with no significant difference in risk of relapse between patients developing full donor and mixed donor chimerism in the T-cell compartment on D+90 and D+180 post transplant. Day 90 full donor T cell chimerism correlated with an increased incidence of acute GVHD according to NIH criteria (p=0.0004) and the subsequent development of chronic GVHD. Consistent with previous observations, our results confirmed a correlation between the establishment of T cell full donor chimerism and acute GVHD in T deplete RIC allografts. However our study failed to identify any correlation between T cell chimerism and relapse risk and challenge the use of pre-emptive donor lymphocyte infusions (DLI) in patients with mixed T cell chimerism transplanted using an alemtuzumab based RIC regimen.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos/administración & dosificación , Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/terapia , Trasplante de Células Madre , Linfocitos T , Quimera por Trasplante , Acondicionamiento Pretrasplante , Adulto , Alemtuzumab , Enfermedad Crónica , Enfermedad Injerto contra Huésped/terapia , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Hermanos , Trasplante Homólogo
7.
N Engl J Med ; 365(15): 1384-95, 2011 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-21995386

RESUMEN

BACKGROUND: Myelodysplastic syndromes are a diverse and common group of chronic hematologic cancers. The identification of new genetic lesions could facilitate new diagnostic and therapeutic strategies. METHODS: We used massively parallel sequencing technology to identify somatically acquired point mutations across all protein-coding exons in the genome in 9 patients with low-grade myelodysplasia. Targeted resequencing of the gene encoding RNA splicing factor 3B, subunit 1 (SF3B1), was also performed in a cohort of 2087 patients with myeloid or other cancers. RESULTS: We identified 64 point mutations in the 9 patients. Recurrent somatically acquired mutations were identified in SF3B1. Follow-up revealed SF3B1 mutations in 72 of 354 patients (20%) with myelodysplastic syndromes, with particularly high frequency among patients whose disease was characterized by ring sideroblasts (53 of 82 [65%]). The gene was also mutated in 1 to 5% of patients with a variety of other tumor types. The observed mutations were less deleterious than was expected on the basis of chance, suggesting that the mutated protein retains structural integrity with altered function. SF3B1 mutations were associated with down-regulation of key gene networks, including core mitochondrial pathways. Clinically, patients with SF3B1 mutations had fewer cytopenias and longer event-free survival than patients without SF3B1 mutations. CONCLUSIONS: Mutations in SF3B1 implicate abnormalities of messenger RNA splicing in the pathogenesis of myelodysplastic syndromes. (Funded by the Wellcome Trust and others.).


Asunto(s)
Síndromes Mielodisplásicos/genética , Fosfoproteínas/genética , Mutación Puntual , Ribonucleoproteína Nuclear Pequeña U2/genética , Eritrocitos/patología , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Fenotipo , Factores de Empalme de ARN
9.
J Clin Pathol ; 62(5): 468-70, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19398596

RESUMEN

Autoimmune haemolysis or thrombocytopenia can complicate purine nucleoside monotherapy for chronic lymphocytic leukaemia (CLL), but Evans syndrome is rare. This is a report of the occurrence of pancytopenia secondary to a unique combination of red cell aplasia with autoimmune thrombocytopenia and neutropenia in a patient with CLL following treatment with fludarabine and cyclophosphamide. This case is unusual for the simultaneous targeting of three haemopoietic lineages by immune dysfunction following fludarabine and cyclophosphamide, which is a treatment regimen believed to reduce autoimmune haematological toxicity in CLL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedades Autoinmunes/inducido químicamente , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Pancitopenia/inducido químicamente , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Vidarabina/administración & dosificación , Vidarabina/efectos adversos , Vidarabina/análogos & derivados
11.
Rapid Commun Mass Spectrom ; 19(23): 3457-62, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16261640

RESUMEN

This paper presents the application of a genetic algorithm (GA) to optimize the operating parameters, namely pulse voltage and extraction delay time, when using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). Simulations predict the presence of several combinations of these parameters that give a local maximum. The aim is to locate the optimal combination (a global maximum) of pulse voltage and extraction time delay in order to focus the ions of a particular m/z value to achieve the best resolution in a given instrumental geometry. The GA locates the global maximum quickly. The results indicate that it may be possible to achieve very high resolving power by using delayed extraction (DE)-MALDI-TOFMS with parameters obtained from the GA.


Asunto(s)
Algoritmos , Marcadores Genéticos/genética , Modelos Genéticos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Humanos
12.
Bone Marrow Transplant ; 35(3): 299-301, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15568036

RESUMEN

Autoimmune haemolytic anaemia (AIHA), immune thrombocytopenia (ITP) and autoimmune neutropenia (AIN) are well-recognised complications of allogeneic stem cell transplantation (SCT), but have previously only been reported in the context of myeloablative conditioning regimens. Management of AIHA, ITP or AIN occurring after allogeneic SCT is unsatisfactory since they frequently prove refractory to conventional therapies including splenectomy. As a consequence, autoimmune cytopenias occurring after allogeneic SCT are associated with substantial morbidity and mortality. We report four patients who developed AIHA or ITP after allogeneic transplantation -- three of which occurred after a reduced-intensity conditioning (RIC) regimen. All patients demonstrated a complete response to Rituximab, having failed to respond to conventional treatment including high-dose prednisolone and intravenous immunoglobulin (IVIg). We conclude that Rituximab can be a valuable agent in the management of autoimmune cytopenias occurring after allogeneic SCT and that autoimmune cytopenias may be a hitherto unrecognised complication of RIC regimens.


Asunto(s)
Anemia Hemolítica Autoinmune/tratamiento farmacológico , Anticuerpos Monoclonales/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Terapia Recuperativa/métodos , Adulto , Anemia Hemolítica Autoinmune/etiología , Anticuerpos Monoclonales de Origen Murino , Manejo de la Enfermedad , Femenino , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/terapia , Humanos , Masculino , Púrpura Trombocitopénica Idiopática/etiología , Rituximab , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo , Resultado del Tratamiento
13.
Bone Marrow Transplant ; 32(3): 273-8, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12858198

RESUMEN

Stem cell transplantation (SCT) may be the only curative option for patients with relapsed or refractory leukaemia, that is, high-risk (HR) leukaemia. Several salvage regimens have been used to cytoreduce disease before SCT, but disease progression or treatment toxicity limits numbers of patients receiving SCT. Here, we report our experience with high-dose cytarabine and amsacrine (Ara-amsa) to salvage patients with HR-leukaemia in the context of SCT. A total of 34 patients with HR-leukaemia (20 AML, 12 ALL, two advanced CML) received 3 g/m(2)/day cytarabine for 5 days and amsacrine 200 mg/m(2)/day for 3 days. Disease response was observed in 62% of patients. Toxicity was limited to neutropenic fever, one patient developed cerebellar toxicity and there was one treatment-related death. A total of 17 patients proceeded to SCT (12 allografts and five autografts). Median survival (OS) of all patients was 10.8 months (95% CI 7.8-21). Patients who were consolidated with SCT after salvage therapy had a superior median OS of 29.4 months (95% CI 12.5-upper limit not reached, n=17) than those who did not receive SCT (6.7 months, CI 1.5-8.6, P<0.0001). Median disease-free survival with SCT (23 months) was higher than after treatment with salvage chemotherapy alone (6.7 months, P=0.0002). Thus Ara-amsa can be used effectively to salvage HR-leukaemia, enabling further consolidation with SCT.


Asunto(s)
Amsacrina/administración & dosificación , Citarabina/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia/terapia , Terapia Recuperativa/métodos , Adolescente , Adulto , Amsacrina/toxicidad , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Citarabina/toxicidad , Femenino , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Leucemia/complicaciones , Leucemia/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
14.
Bone Marrow Transplant ; 31(9): 763-6, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12732882

RESUMEN

Patients with Philadelphia positive (Ph(+)) adult acute lymphoblastic leukaemia (ALL) have a poor prognosis. Stem cell transplantation (SCT) is increasingly being recognised as the treatment of choice in eligible patients with Ph(+)ALL, but disease-relapse remains a problem in a proportion of patients prior to and after SCT. Genetic abnormalities in addition to the Ph chromosome may influence the biology and clinical course of ALL, but there are not many studies on the potential genetic heterogeneity of adult Ph(+)ALL and clinical outcomes. Here, we report on five patients with ALL who were double Ph(+) and also had a high-hyperdiploid karyotype (Ph(+)/hyperdiploid) at diagnosis. In contrast to the presence of the Ph(+) chromosome, high-hyperdiploidy (>50 chromosomes) as the sole karyotypic abnormality in ALL is associated with a favourable clinical outcome. In our series, four patients with a Ph(+)/hyperdiploid karyotype achieved a cytogenetic remission after induction chemotherapy and proceeded to stem cell transplantation (SCT). The fifth had five subclones including Ph(+)/hyperdiploid, as well as those that were only Ph(+); the latter emerged as the dominant clone after induction therapy and the patient died of disease-relapse. Of the patients who underwent SCT, only one relapsed, but achieved a durable remission with donor lymphocyte infusions. Thus, it is conceivable that the presence of high-hyperdiploidy as an additional karyotypic abnormality may confer a better prognosis to Ph(+)ALL, presumably by altering the kinetics of Ph(+) neoplastic cells. We have discussed these results in the context of recent studies on the significance of high-hyperdiploidy in Ph(+) adult ALL.


Asunto(s)
Diploidia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Pronóstico , Inducción de Remisión , Resultado del Tratamiento
15.
Bone Marrow Transplant ; 30(7): 471-3, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12368962

RESUMEN

The disease-free survival of patients with myeloma and severe renal failure after high-dose melphalan and autologous stem cell rescue is similar to those with normal renal function at the time of the autograft. However, recovery of renal function after intensive treatment is uncommon and patients with end-stage renal failure continue to be dialysis-dependent. We report two patients with myeloma who required regular haemodialysis from diagnosis, but became dialysis-independent after a high-dose melphalan autograft. Thus, in some patients, renal function may be partially salvageable despite the requirement for dialysis at the time of autografting.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Fallo Renal Crónico/terapia , Mieloma Múltiple/complicaciones , Mieloma Múltiple/terapia , Supervivencia sin Enfermedad , Humanos , Fallo Renal Crónico/etiología , Pruebas de Función Renal , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Trasplante Autólogo
16.
Leukemia ; 16(5): 785-90, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11986938

RESUMEN

The potential contribution of abnormal marrow stromal function to ineffective haemopoiesis in the myelodysplastic syndromes is unclear. We have compared the ability of stromal layers from normal (n = 7) and myelodysplastic (n = 9) marrow to alter proliferation and survival of the granulocyte-macrophage colony-stimulating factor/interleukin-3-dependent cell line F-36P. Co-cultures for 72 h in the absence of exogenous cytokines were either in direct contact with stroma or separated by transwell inserts. On normal stromal layers, the ratio of adherent F-36P cells relative to stromal cells increased from a mean of 0.2 +/- 0.01 (s.d.) at 4 h of co-culture to 0.34 +/- 0.08 after 72 h (n = 7). Corresponding values on myelodysplastic stroma (0.2 +/- 0.02 at 4 h and 0.35 +/- 0.05 at 72 h; n = 9) indicated that the ability of myelodysplastic stromal layers to regulate short-term proliferation of F-36P cells may be similar to normal. Apoptosis of F-36P cells was quantified after co-culture with normal or myelodysplastic stroma: results from myelodysplastic co-cultures were standardized as a fraction of values from co-cultures with paired normal stroma (apoptotic ratio). Augmented apoptosis of F-36P cells was detected in 8/9 co-cultures with myelodysplastic stroma (mean = 15.7 +/- 9.7%, n = 9), compared with corresponding normal stroma (mean = 12.4 +/- 4.6%, n = 7, P < 0.05) with a mean apoptotic ratio of 1.4 +/- 0.5 (P < 0.05). There was no correlation between stroma-related apoptosis and FAB type, tumour necrosis factor-alpha concentrations in the culture supernatant or numbers of stromal macrophages, and no evidence of involvement of the Fas pathway. Increased apoptosis was detected in cells grown in transwell inserts over stroma (23.8 +/- 3%, n = 5) compared to adherent cells in cultures with normal stromal layers, but this survival difference was not observed in co-cultures with myelodysplastic stroma. These results suggest that abnormal stromal function in patients with myelodysplastic syndromes may contribute to increased apoptosis of haemopoietic cells within the marrow microenvironment. The effect appears to be dependent on close cellular contact, rather than the release of soluble factors, but the exact mechanism remains unclear.


Asunto(s)
Células de la Médula Ósea/patología , Comunicación Celular , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/fisiopatología , Células del Estroma/patología , Anciano , Apoptosis , Estudios de Casos y Controles , División Celular , Línea Celular , Supervivencia Celular , Técnicas de Cocultivo , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Células Madre Hematopoyéticas/citología , Humanos , Interleucina-3
17.
Haematologica ; 86(10): 1038-45, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11602409

RESUMEN

BACKGROUND AND OBJECTIVES: The regulation of hematopoiesis by marrow stroma in vitro, has been shown to be abnormal in some patients with myelodysplastic syndromes (MDS). This study was performed to assess whether a range of mechanisms may be altered within the MDS microenvironment. DESIGN AND METHODS: The effects of diffusible factors produced by normal or MDS stromal layers on hematopoietic cells were studied by comparing the ability of media conditioned (CM) by normal or MDS stroma to regulate migration of target normal marrow CD34+ cells across 5 microm transmembranes. The ability of CM to stimulate hematopoietic cells was also assessed: changes in membrane polarity of KG-1a cells on exposure to stroma CM were compared. Subsequently, contact-mediated interactions between normal marrow CD34+ cells and normal and MDS stroma were studied: survival of allogeneic normal marrow CD34+ cells on live and glutaraldehyde-fixed normal and myelodysplastic stroma after 24h of co-culture was measured using 7-aminoactinomycin D staining. To determine whether hematopoietic cell survival on normal and MDS stroma was related to oxidative stress within the stromal microenvironment, intracellular superoxide levels, both constitutively and induced by tumor necrosis factor-a were measured within live stromal cells by FACScan analysis of ethidium bromide stained cells. RESULTS: The ability of CM from normal and MDS stroma to regulate short-term migration and activation of hematopoietic cells was similar. The mean percentage of apoptotic CD34+ cells (13+/-11%) adherent to glutaraldehyde-fixed myelodysplastic stroma was higher than on paired fixed normal stroma (11+/-10%) (n=6, p=0.056). Constitutive mean levels of superoxide in myelodysplastic cultures (9.5+/-2.1) were greater than in normal stromal cultures (4.9+/-0.6; n=6). However, following treatment with tumor necrosis factor-a, the mean value for superoxide in myelodysplastic stromal cultures was unchanged (fractional change=0.99+/-0.56), compared with an increase in normal stroma (fractional change=1.6+/-0.1, p<0.05). No correlation was observed between superoxide levels, proportion of apoptotic CD34+ cells and percentage of CD14+ stromal cells [mean 8%, range 0-37% (myelodysplastic); mean 1.3%, range 0-5% (normal)]. INTERPRETATION AND CONCLUSIONS: Abnormalities of stromal function in myelodysplastic syndromes are likely to be heterogeneous in origin: altered matrix molecules and changes in superoxide within stromal cells may contribute to abnormal survival and development of hematopoietic cells within the myelodysplastic marrow microenvironment


Asunto(s)
Hematopoyesis , Síndromes Mielodisplásicos/patología , Células del Estroma/patología , Células del Estroma/fisiología , Anciano , Anciano de 80 o más Años , Células de la Médula Ósea/patología , Células de la Médula Ósea/fisiología , Técnicas de Cultivo de Célula , Medios de Cultivo Condicionados/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/fisiología , Humanos , Persona de Mediana Edad , Superóxidos/metabolismo
18.
Bone Marrow Transplant ; 27(7): 757-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11360118

RESUMEN

Abnormalities of immune surveillance may contribute to the development of myeloid malignancy as well as immune-mediated diseases. In leukaemia, allogeneic haemopoietic stem cell transplantation (alloHSCT) has been used to induce disease remission, in part by restoring mechanisms of immune regulation. Although, by the same principle, allogeneic stem cell transplantation is an attractive option for the treatment of immunological disorders, it is unclear whether remission after transplantation is due to pre-transplant conditioning, or modulation of auto-reactive lymphocytes by cells in the allograft. We report the case of a patient with chronic myeloid leukaemia (CML) who received an allogeneic bone marrow transplant (alloBMT) from his brother. He subsequently suffered a cytogenetic and molecular relapse of CML. At the same time, sarcoidosis involving the marrow was diagnosed. He was treated with donor lymphocyte infusions (DLI) and attained remission from CML; in addition, no giant cell granulomas were detected in the marrow, indicating resolution of sarcoidosis. This case illustrates the need for further studies on the role of T cell-based therapies in the management of immune-mediated disorders.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Transfusión de Linfocitos , Sarcoidosis/etiología , Adulto , Supervivencia sin Enfermedad , Humanos , Inmunoterapia , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Masculino , Núcleo Familiar , Recurrencia , Sarcoidosis/sangre , Sarcoidosis/terapia , Trasplante Homólogo/efectos adversos
19.
Bone Marrow Transplant ; 26(9): 1017-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11100283

RESUMEN

Patients who undergo splenectomy and recipients of allogeneic marrow (alloBMT) or peripheral stem cell transplantation are at increased risk of overwhelming infection from encapsulated organisms such as Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis. As prophylaxis against these pathogens splenectomised patients are immunised and may also receive antibiotics for life. We report relapsing overwhelming sepsis caused by penicillin-resistant pneumococcus in a patient who was immunised and received prophylactic phenoxymethylpenicillin for 8 months following splenectomy and matched unrelated donor (MUD) marrow transplantation for refractory T cell lymphoma. No obvious focus of sepsis was found during any of the three episodes and S. pneumoniae serogroup 6, subtype 6B was isolated from blood cultures on each occasion. He was treated with i.v. cephalosporins, as the organisms were resistant to penicillin with a minimum inhibitory concentration (MIC) of 2.0, and there was complete resolution of symptoms each time. In the light of recurrent sepsis with this penicillin-resistant organism the decision was made to give prophylactic levofloxacin for the next 12 months. This case illustrates that the choice of prophylactic regimen and the treatment of sepsis in immunocompromised patients remain difficult and challenging issues.


Asunto(s)
Bacteriemia/etiología , Trasplante de Médula Ósea , Linfoma de Células T/terapia , Resistencia a las Penicilinas , Infecciones Neumocócicas/etiología , Streptococcus pneumoniae/efectos de los fármacos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Carmustina/administración & dosificación , Cefotaxima/uso terapéutico , Terapia Combinada , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Infecciones por Citomegalovirus/etiología , Doxorrubicina/administración & dosificación , Quimioterapia Combinada/uso terapéutico , Etopósido/administración & dosificación , Humanos , Idarrubicina/administración & dosificación , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Levofloxacino , Linfoma de Células T/tratamiento farmacológico , Linfoma de Células T/cirugía , Masculino , Melfalán/administración & dosificación , Ofloxacino/uso terapéutico , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/microbiología , Prednisona/administración & dosificación , Recurrencia , Rifampin/uso terapéutico , Esplenectomía , Streptococcus pneumoniae/aislamiento & purificación , Acondicionamiento Pretrasplante/efectos adversos , Vincristina/administración & dosificación
20.
Bone Marrow Transplant ; 26(7): 795-6, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11042663

RESUMEN

Herpes zoster infections are frequently observed after allogeneic bone marrow transplantation (alloBMT). In the majority of cases, the infection is restricted to specific dermatomes and responds to oral acyclovir, without visceral dissemination. We report the case of a 40-year-old male who developed dermatomal herpetic infection 8 months post alloBMT. The herpetic rash responded well to treatment with high-dose oral acyclovir. However, within a week of cessation of therapy, the patient re-presented with dermatomal zoster and meningoencephalitis. Although the cutaneous lesions resolved with intravenous acyclovir, clinical features of meningoencephalitis persisted, along with evidence of varicella zoster virus (VZV) DNA in cerebrospinal fluid (CSF). A satisfactory response to treatment was observed only after the addition of intravenous foscarnet to acyclovir. Based on our experience with this patient, we suggest that in a subset of alloBMT recipients, late dermatomal herpes zoster infections may respond only partially to treatment with standard oral acyclovir. The use of oral acyclovir preparations with higher bioavailability (valacyclovir) or intravenous acyclovir early on may prevent the considerable morbidity associated with disseminated zoster infection. Bone Marrow Transplantation (2000) 26, 795-796.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Encefalitis por Varicela Zóster/tratamiento farmacológico , Encefalitis por Varicela Zóster/etiología , Herpes Zóster/etiología , Aciclovir/administración & dosificación , Adulto , Antivirales/administración & dosificación , ADN Viral/líquido cefalorraquídeo , Encefalitis por Varicela Zóster/virología , Foscarnet/administración & dosificación , Herpes Zóster/complicaciones , Herpes Zóster/tratamiento farmacológico , Herpesvirus Humano 3/genética , Humanos , Masculino , Enfermedades de la Piel/virología , Trasplante Homólogo/efectos adversos
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