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1.
ESMO Open ; 8(4): 101610, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37536254

RESUMEN

BACKGROUND: Investigation of the disparities in the access to experimental treatment in early-phase clinical trials is lacking. The objective of the EGALICAN-2 study was to identify the factors underpinning such inequalities. METHODS: A national prospective survey was conducted in 11 early-phase clinical trial centers (CLIP2) certified by the French National Cancer Institute. Sociodemographic, socioeconomic and medical data were collected. Univariate logistic regression models were carried out to estimate odds ratios and 90% confidence intervals associated with the effect of each study variable. A multivariate logistic regression model was built to explore the independent factors associated with the administration of the experimental treatment (C1D1). A post hoc analysis was carried out excluding female cancer patients. RESULTS: Between 2015 and 2016, 1355 patients referred from 11 CLIP2 centers in France were included in the study. Eight hundred and forty-eight patients received C1D1 (73%) and 320 patients (27%) were screening failure. Median age was 58 years (range 17-97 years) and 667 patients (54%) were female. Most patients had a metastatic disease (n = 751, 87%). In the multivariate logistic regression analysis, the significant independent factors associated with C1D1 were male sex, initial care received in a hospital with an early-phase unit and living in wealthy metropolitan areas (P values <0.05). In the post hoc analysis, the sex factor was no longer significant [odds ratio = 1.21 (95% confidence interval 0.86-1.70), P value = 0.271]. CONCLUSIONS: This study investigated the factors producing social inequalities in the context of early-phase clinical trials in oncology. Our research highlights factors of sex, care pathway and geographic location. Gynecological cancer was found to impact C1D1 significantly, unlike breast cancer. The results of this study should contribute to improve patient access to early-phase clinical trials.


Asunto(s)
Neoplasias de la Mama , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Francia/epidemiología , Neoplasias de la Mama/diagnóstico
2.
ESMO Open ; 7(3): 100468, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35533427

RESUMEN

BACKGROUND: Access to clinical trials and especially early-phase trials (ECT) is an important issue in geriatric oncology. As cancer can be considered an age-related disease because the incidence of most cancers increases with age, new drugs should also be evaluated in older patients to assess their safety and efficacy. The EGALICAN-2 study was primarily designed to identify social and/or regional inequalities regarding access to ECT. We focused on the factors of inequalities in access to ECT in older patients. PATIENTS AND METHODS: During a 1-year period (2015-2016), a survey was conducted in 11 early-phase units certified by the French National Cancer Institute. RESULTS: A total of 1319 patients were included in the analyses: 1086 patients (82.3%) were <70 years and 233 patients (17.7%) were >70 years. The most common tumor types at referral in older patients were gastrointestinal (19.3%), hematological (19.3%), and thoracic tumors (18.0%). Most patients referred to the phase I unit had signed informed consent and the rate was similar across age (92.7% in younger patients versus 90.6% in older patients; P = 0.266). The rate of screening failure was also similar across age (28.5% in younger patients versus 24.3% in older patients; P = 0.219). Finally, in older patients, univariate analyses showed that initial care received in the hospital having a phase I unit was statistically associated with first study drug administration (odds ratio 0.49, 90% confidence interval 0.27-0.88; P = 0.045). CONCLUSIONS: Older patients are underrepresented in early clinical trials with 17.7% of patients aged ≥70 years compared with the number of new cases of cancer in France (50%). However, when invited to participate, older patients were prone to sign informed consent.


Asunto(s)
Neoplasias , Anciano , Ensayos Clínicos como Asunto , Francia/epidemiología , Humanos , Incidencia , Neoplasias/tratamiento farmacológico , Neoplasias/terapia
3.
ESMO Open ; 7(2): 100403, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35272130

RESUMEN

BACKGROUND: The COVID-19 pandemic has created enormous challenges for the clinical management of patients with hematological malignancies (HMs), raising questions about the optimal care of this patient group. METHODS: This consensus manuscript aims at discussing clinical evidence and providing expert advice on statements related to the management of HMs in the COVID-19 pandemic. For this purpose, an international consortium was established including a steering committee, which prepared six working packages addressing significant clinical questions from the COVID-19 diagnosis, treatment, and mitigation strategies to specific HMs management in the pandemic. During a virtual consensus meeting, including global experts and lead by the European Society for Medical Oncology and the European Hematology Association, statements were discussed and voted upon. When a consensus could not be reached, the panel revised statements to develop consensual clinical guidance. RESULTS AND CONCLUSION: The expert panel agreed on 33 statements, reflecting a consensus, which will guide clinical decision making for patients with hematological neoplasms during the COVID-19 pandemic.


Asunto(s)
COVID-19 , Neoplasias Hematológicas , Humanos , Consenso , Prueba de COVID-19 , Neoplasias Hematológicas/epidemiología , Neoplasias Hematológicas/terapia , Pandemias
5.
Rev Med Interne ; 30(10): 886-9, 2009 Oct.
Artículo en Francés | MEDLINE | ID: mdl-19748163

RESUMEN

INTRODUCTION: Fever during a myelodysplastic syndrome can be due to infectious complications, systemic disease or acute transformation with clonal evolution. CASE REPORT: A 51-year-old woman, with a 5q- syndrome and neutropenia, presented with a several week fever duration. Infectious work-up was negative and therapy with antibiotics had no influence on the clinical course. Neither bone marrow nor blood blasts were detected, but liver biopsy demonstrated significant blast infiltration compatible with the diagnosis of acute myeloid leukaemia (AML). CONCLUSION: The absence of blasts in blood or bone marrow does not exclude the malignant transformation of a myelodysplastic syndrome to AML. Tissue biopsy may be necessary to confirm the leukaemic progression.


Asunto(s)
Fiebre/etiología , Leucemia Mieloide Aguda/diagnóstico , Síndromes Mielodisplásicos/complicaciones , Femenino , Humanos , Infiltración Leucémica , Hígado/patología , Persona de Mediana Edad
6.
Leuk Res ; 71: 82-88, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30025280

RESUMEN

BACKGROUND: The Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) are associated with increases in janus kinase 2 (JAK2) signaling, often resulting from the JAK2 V617F mutation. LY2784544 (gandotinib) is a potent, selective, small-molecule inhibitor of JAK2 that has potential dose-dependent selectivity for the JAK2 V617F mutation and may inhibit additional JAK2 mutant isoforms in nonclinical testing. METHODS: A multicenter, single-arm, outpatient phase 2 study evaluated the efficacy, safety, and pharmacokinetics (PK) of gandotinib administered to patients (120 mg once daily) with MPNs, including polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF). Between May 2012 and March 2015, 138 patients received at least one dose of study drug. FINDINGS: Most frequent Grade 3 or 4 treatment-emergent adverse events that were considered study-drug related were anemia (11.6%), hyperuricemia (3.2%), fatigue (2.9%), diarrhea (2.2%), and thrombocytopenia (2.2%). Overall response rates (ORRs) in patients with JAK2 V617F-mutated PV, ET, and MF were 95%, 90.5%, and 9.1%, respectively, while patients with ET and MF without the JAK2 V617F mutations had ORRs of 43.7% and 0%, respectively. INTERPRETATIONS: LY2784544 demonstrated efficacy in JAK2 V617F-mutated MPNs, including in patients previously on ruxolitinib therapy, who had an ORR of 3.3%. At the 1-year visit, 44% of patients experienced a ≥50% improvement in the MPN-Symptom Assessment Form Total Symptom Score, and 26% of patients had a 50% reduction in Brief Fatigue Inventory score.


Asunto(s)
Antineoplásicos/uso terapéutico , Imidazoles/uso terapéutico , Policitemia Vera/tratamiento farmacológico , Mielofibrosis Primaria/tratamiento farmacológico , Pirazoles/uso terapéutico , Piridazinas/uso terapéutico , Trombocitemia Esencial/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Janus Quinasa 2/genética , Masculino , Persona de Mediana Edad , Mutación , Trastornos Mieloproliferativos/tratamiento farmacológico , Trastornos Mieloproliferativos/genética , Policitemia Vera/genética , Trombocitemia Esencial/genética
7.
Leukemia ; 20(3): 463-70, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16408099

RESUMEN

Natural Killer (NK) cells are critical in host defense against malignant transformation and are potent antileukemic cytotoxic effectors. In the present study, we investigated the peripheral NK function in patients with myelodysplastic syndromes (MDS). We demonstrated that the peripheral NK cell population was quantitatively normal in MDS patients. Furthermore, NK cells displayed an expression of the activating natural cytotoxicity receptors (NCR) NKp46 and NKp30 as well as NKG2D similar to that observed in donors, but exert a highly decreased constitutive cytolytic activity compared to resting normal NK cells. Although activation with IL-2 resulted in the upregulation of NKp46 expression by MDS-NK cells, their cytolytic function remained deeply altered as compared to activated donor NK cells. In addition, MDS NK cells did not proliferate in vitro, and displayed an increased rate of apoptosis in response to IL-2 stimulation although the spontaneous apoptosis was not significantly increased. Interestingly, a proportion of peripheral MDS-NK cells were derived from the MDS clone as the cytogenetic anomaly found in bone marrow karyotype was also detected in 20-50% of circulating NK cells. In conclusion, NK cells' cytolytic function and proliferative capacities in response to activation by cytokines are profoundly altered in MDS.


Asunto(s)
Citotoxicidad Inmunológica , Células Asesinas Naturales/inmunología , Síndromes Mielodisplásicos/inmunología , Apoptosis , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Cariotipificación
8.
Leukemia ; 31(8): 1661-1670, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28484264

RESUMEN

Malignant hematological diseases are mainly because of the occurrence of molecular abnormalities leading to the deregulation of signaling pathways essential for precise cell behavior. High-resolution genome analysis using microarray and large-scale sequencing have helped identify several important acquired gene mutations that are responsible for such signaling deregulations across different hematological malignancies. In particular, the genetic landscape of classical myeloproliferative neoplasms (MPNs) has been in large part completed with the identification of driver mutations (targeting the cytokine receptor/Janus-activated kinase 2 (JAK2) pathway) that determine MPN phenotype, as well as additional mutations mainly affecting the regulation of gene expression (epigenetics or splicing regulators) and signaling. At present, most efforts concentrate in understanding how all these genetic alterations intertwine together to influence disease evolution and/or dictate clinical phenotype in order to use them to personalize diagnostic and clinical care. However, it is now evident that factors other than somatic mutations also play an important role in MPN disease initiation and progression, among which germline predisposition (single-nucleotide polymorphisms and haplotypes) may strongly influence the occurrence of MPNs. In this context, the LNK inhibitory adaptor protein encoded by the LNK/SH2B adaptor protein 3 (SH2B3) gene is the target of several genetic variations, acquired or inherited in MPNs, lymphoid leukemia and nonmalignant hematological diseases, underlying its importance in these pathological processes. As LNK adaptor is a key regulator of normal hematopoiesis, understanding the consequences of LNK variants on its protein functions and on driver or other mutations could be helpful to correlate genotype and phenotype of patients and to develop therapeutic strategies to target this molecule. In this review we summarize the current knowledge of LNK function in normal hematopoiesis, the different SH2B3 mutations reported to date and discuss how these genetic variations may influence the development of hematological malignancies.


Asunto(s)
Enfermedades Hematológicas/genética , Mutación , Trastornos Mieloproliferativos/genética , Proteínas/genética , Proteínas Adaptadoras Transductoras de Señales , Animales , Neoplasias Hematológicas/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Janus Quinasa 2/genética , Policitemia/genética , Proteínas/química , Proteínas/fisiología
9.
Leukemia ; 31(4): 882-888, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27740634

RESUMEN

Ruxolitinib is an oral Janus-activated kinase 1 (JAK1)/JAK2 inhibitor approved for the treatment of patients with myelofibrosis based on the results of two randomized clinical trials. However, discordant indications were provided by regulatory agencies and scientific societies for selecting the most appropriate candidates to this drug. The European LeukemiaNet and the Italian Society of Hematology shared the aim of building evidence-based recommendations for the use of ruxolitinib according to the GRADE methodology. Eighteen patient-intervention-comparator-outcome profiles were listed, each of them comparing ruxolitinib to other therapies with the aim of improving one of the three clinical outcomes: (a) splenomegaly, (b) disease-related symptoms, and (c) survival. Ruxolitinib was strongly recommended for improving symptomatic or severe (>15 cm below the costal margin) splenomegaly in patients with an International Prognostic Scoring System (IPSS)/dynamic IPSS risk intermediate 2 or high. Ruxolitinib was also strongly recommended for improving systemic symptoms in patients with an MPN10 score >44, refractory severe itching, unintended weight loss not attributable to other causes or unexplained fever. Because of weak evidence, the panel does not recommend ruxolitinib therapy for improving survival. Also, the recommendations given above do not necessarily apply to patients who are candidates for allogeneic stem cell transplant.


Asunto(s)
Terapia Molecular Dirigida , Mielofibrosis Primaria/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirazoles/uso terapéutico , Comorbilidad , Hemorragia/etiología , Humanos , Hipertensión Portal/etiología , Infecciones/etiología , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 2/antagonistas & inhibidores , Nitrilos , Fenotipo , Mielofibrosis Primaria/diagnóstico , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/mortalidad , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Pirazoles/administración & dosificación , Pirazoles/efectos adversos , Pirimidinas , Esplenomegalia , Resultado del Tratamiento
10.
Leukemia ; 31(4): 896-902, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27773929

RESUMEN

RBC-transfusion dependence is common in persons with myeloproliferative neoplasm (MPN)-associated myelofibrosis. The objective of this study was to determine the rates of RBC-transfusion independence after therapy with pomalidomide vs placebo in persons with MPN-associated myelofibrosis and RBC-transfusion dependence. Two hundred and fifty-two subjects (intent-to-treat (ITT) population) including 229 subjects confirmed by central review (modified ITT population) were randomly assigned (2:1) to pomalidomide or placebo. Trialists and subjects were blinded to treatment allocation. Primary end point was proportion of subjects achieving RBC-transfusion independence within 6 months. One hundred and fifty-two subjects received pomalidomide and 77 placebo. Response rates were 16% (95% confidence interval (CI), 11, 23%) vs 16% (8, 26%; P=0.87). Response in the pomalidomide cohort was associated with ⩽4 U RBC/28 days (odds ratio (OR)=3.1; 0.9, 11.1), age ⩽65 (OR=2.3; 0.9, 5.5) and type of MPN-associated myelofibrosis (OR=2.6; 0.7, 9.5). Responses in the placebo cohort were associated with ⩽4 U RBC/28 days (OR=8.6; 0.9, 82.3), white blood cell at randomization >25 × 109/l (OR=4.9; 0.8, 28.9) and interval from diagnosis to randomization >2 years (OR=4.9; 1.1, 21.9). Pomalidomide was associated with increased rates of oedema and neutropenia but these adverse effects were manageable. Pomalidomide and placebo had similar RBC-transfusion-independence response rates in persons with MPN-associated RBC-transfusion dependence.


Asunto(s)
Factores Inmunológicos/uso terapéutico , Trastornos Mieloproliferativos/complicaciones , Mielofibrosis Primaria/etiología , Mielofibrosis Primaria/terapia , Talidomida/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Transfusión de Eritrocitos/métodos , Femenino , Humanos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/efectos adversos , Masculino , Persona de Mediana Edad , Trastornos Mieloproliferativos/diagnóstico , Fenotipo , Mielofibrosis Primaria/diagnóstico , Talidomida/administración & dosificación , Talidomida/efectos adversos , Talidomida/uso terapéutico , Resultado del Tratamiento , Flujo de Trabajo
11.
Leukemia ; 31(12): 2726-2731, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28561069

RESUMEN

Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms with variable risk of evolution into post-PV and post-ET myelofibrosis, from now on referred to as secondary myelofibrosis (SMF). No specific tools have been defined for risk stratification in SMF. To develop a prognostic model for predicting survival, we studied 685 JAK2, CALR, and MPL annotated patients with SMF. Median survival of the whole cohort was 9.3 years (95% CI: 8-not reached-NR-). Through penalized Cox regressions we identified negative predictors of survival and according to beta risk coefficients we assigned 2 points to hemoglobin level <11 g/dl, to circulating blasts ⩾3%, and to CALR-unmutated genotype, 1 point to platelet count <150 × 109/l and to constitutional symptoms, and 0.15 points to any year of age. Myelofibrosis Secondary to PV and ET-Prognostic Model (MYSEC-PM) allocated SMF patients into four risk categories with different survival (P<0.0001): low (median survival NR; 133 patients), intermediate-1 (9.3 years, 95% CI: 8.1-NR; 245 patients), intermediate-2 (4.4 years, 95% CI: 3.2-7.9; 126 patients), and high risk (2 years, 95% CI: 1.7-3.9; 75 patients). Finally, we found that the MYSEC-PM represents the most appropriate tool for SMF decision-making to be used in clinical and trial settings.


Asunto(s)
Policitemia Vera/genética , Policitemia Vera/mortalidad , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/mortalidad , Trombocitemia Esencial/genética , Trombocitemia Esencial/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación , Policitemia Vera/diagnóstico , Mielofibrosis Primaria/diagnóstico , Pronóstico , Factores de Riesgo , Análisis de Supervivencia , Trombocitemia Esencial/diagnóstico
12.
Leukemia ; 30(4): 776-81, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26601783

RESUMEN

Interferon alpha (IFN-α) has been used for over 30 years to treat myeloproliferative neoplasms (MPNs). IFN-α was shown to induce clinical, hematological, molecular and histopathological responses in small clinical studies. Such combined efficacy has never been achieved with any other drug to date in such a significant proportion of patients. However, toxicity remains a limitation to its broader use despite the development of pegylated forms with better tolerance. Several on going phase 3 studies of peg- IFN-α versus hydroxyurea will help to define its exact place in MPN management. IFN-α efficacy is likely the consequence of a broad range of biological properties, including enhancement of immune response, direct effects on malignant cells and ability to cycle dormant malignant stem cells. However, comprehensive elucidation of its mechanism of action is still lacking. Sustained clinical, molecular and morphological responses after IFN-α discontinuation raised the hope that this drug could eradicate MPN. There is now consistent evidence showing that IFN-α is able to eliminate malignant clones harboring JAK2V617F or Calreticulin mutations. However, the molecular complexity of these diseases could hamper IFN-α efficacy, as the presence of additional non-driver mutations, like in the TET2 gene, could be associated with resistance to IFN-α. Therefore, combined therapy with another targeted agent could be required to eradicate MPN, and the best IFN-α companion for achieving this challenge remains to be determined.


Asunto(s)
Antivirales/uso terapéutico , Interferón-alfa/uso terapéutico , Trastornos Mieloproliferativos/tratamiento farmacológico , Humanos
13.
Leukemia ; 30(8): 1701-7, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27211272

RESUMEN

Ruxolitinib is a Janus kinase (JAK) (JAK1/JAK2) inhibitor that has demonstrated superiority over placebo and best available therapy (BAT) in the Controlled Myelofibrosis Study with Oral JAK Inhibitor Treatment (COMFORT) studies. COMFORT-II was a randomized (2:1), open-label phase 3 study in patients with myelofibrosis; patients randomized to BAT could crossover to ruxolitinib upon protocol-defined disease progression or after the primary end point, confounding long-term comparisons. At week 48, 28% (41/146) of patients randomized to ruxolitinib achieved ⩾35% decrease in spleen volume (primary end point) compared with no patients on BAT (P<0.001). Among the 78 patients (53.4%) in the ruxolitinib arm who achieved ⩾35% reductions in spleen volume at any time, the probability of maintaining response was 0.48 (95% confidence interval (CI), 0.35-0.60) at 5 years (median, 3.2 years). Median overall survival was not reached in the ruxolitinib arm and was 4.1 years in the BAT arm. There was a 33% reduction in risk of death with ruxolitinib compared with BAT by intent-to-treat analysis (hazard ratio (HR)=0.67; 95% CI, 0.44-1.02; P=0.06); the crossover-corrected HR was 0.44 (95% CI, 0.18-1.04; P=0.06). There was no unexpected increased incidence of adverse events with longer exposure. This final analysis showed that spleen volume reductions with ruxolitinib were maintained with continued therapy and may be associated with survival benefits.


Asunto(s)
Mielofibrosis Primaria/tratamiento farmacológico , Pirazoles/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Estudios Cruzados , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Nitrilos , Tamaño de los Órganos/efectos de los fármacos , Mielofibrosis Primaria/mortalidad , Pirimidinas , Bazo , Tasa de Supervivencia
14.
Leukemia ; 30(5): 1018-24, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26854026

RESUMEN

The Philadelphia-negative myeloproliferative neoplasms (MPNs) are clonal disorders involving hematopoietic stem and progenitor cells and are associated with myeloproliferation, splenomegaly and constitutional symptoms. Similar signs and symptoms can also be found in patients with chronic inflammatory diseases, and inflammatory processes have been found to play an important role in the pathogenesis and progression of MPNs. Signal transduction pathways involving JAK1, JAK2, STAT3 and STAT5 are causally involved in driving both the malignant cells and the inflammatory process. Moreover, anti-inflammatory and immune-modulating drugs have been used successfully in the treatment of MPNs. However, to date, many unresoved issues remain. These include the role of somatic mutations that are present in addition to JAK2V617F, CALR and MPL W515 mutations, the interdependency of malignant and nonmalignant cells and the means to eradicate MPN-initiating and -maintaining cells. It is imperative for successful therapeutic approaches to define whether the malignant clone or the inflammatory cells or both should be targeted. The present review will cover three aspects of the role of inflammation in MPNs: inflammatory states as important differential diagnoses in cases of suspected MPN (that is, in the absence of a clonal marker), the role of inflammation in MPN pathogenesis and progression and the use of anti-inflammatory drugs for MPNs. The findings emphasize the need to separate the inflammatory processes from the malignancy in order to improve our understanding of the pathogenesis, diagnosis and treatment of patients with Philadelphia-negative MPNs.


Asunto(s)
Inflamación/tratamiento farmacológico , Trastornos Mieloproliferativos/tratamiento farmacológico , Neoplasias/patología , Antiinflamatorios/uso terapéutico , Células Clonales/patología , Humanos , Trastornos Mieloproliferativos/patología
15.
Leukemia ; 11(11): 1821-6, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9369413

RESUMEN

Essential thrombocythemia (ET) is a myeloproliferative disorder associated with megakaryocytic hyperplasia and thrombocytosis. In this disease, in vitro autonomous growth of megakaryocytic colonies has been demonstrated by various investigators. This phenomenon is impaired by the inhibition of the thrombopoietin/c-mpl pathway. In order to evaluate the potential role of mutations of the receptor gene in the origin of this autonomous growth, we compared the expression of c-mpl mRNA isoforms in platelets derived from ET patients and normal subjects. Overlapping c-mpl PCR fragments derived from four ET patients were sequenced to search for small mutations. In the 10 ET and five normal samples we studied, relative expression of the c-mpl isoforms was identical. New variants of Mpl-P and K isoforms, Mpl-P2 and K2 were detected. Cloning of these isoforms indicated that they are produced by alternative splicing of exon 9 sequences shared by Mpl-P and K. Their predicted amino acid sequence would be deleted by 24 aminoacids, upstream of the WSSWS box of the second domain of c-mpl. Two sequence variations, leading to DNA restriction polymorphisms, were present in the extracellular and Mpl-K intracytoplasmic domains. Both were present in normal and ET samples, excluding mutations of c-mpl as a cause of ET.


Asunto(s)
Plaquetas/metabolismo , Proteínas de Neoplasias , Proteínas Proto-Oncogénicas/genética , Receptores de Citocinas , Trombocitemia Esencial/genética , Secuencia de Aminoácidos , Secuencia de Bases , Cartilla de ADN , Exones , Humanos , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Proteínas Proto-Oncogénicas/metabolismo , Receptores de Trombopoyetina , Análisis de Secuencia de ADN , Trombocitemia Esencial/metabolismo
16.
Leukemia ; 29(1): 20-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25151955

RESUMEN

The discovery of somatic mutations, primarily JAK2V617F and CALR, in classic BCR-ABL1-negative myeloproliferative neoplasms (MPNs) has generated interest in the development of molecularly targeted therapies, whose accurate assessment requires a standardized framework. A working group, comprised of members from European LeukemiaNet (ELN) and International Working Group for MPN Research and Treatment (IWG-MRT), prepared consensus-based recommendations regarding trial design, patient selection and definition of relevant end points. Accordingly, a response able to capture the long-term effect of the drug should be selected as the end point of phase II trials aimed at developing new drugs for MPNs. A time-to-event, such as overall survival, or progression-free survival or both, as co-primary end points, should measure efficacy in phase III studies. New drugs should be tested for preventing disease progression in myelofibrosis patients with early disease in randomized studies, and a time to event, such as progression-free or event-free survival should be the primary end point. Phase III trials aimed at preventing vascular events in polycythemia vera and essential thrombocythemia should be based on a selection of the target population based on new prognostic factors, including JAK2 mutation. In conclusion, we recommended a format for clinical trials in MPNs that facilitates communication between academic investigators, regulatory agencies and drug companies.


Asunto(s)
Consenso , Determinación de Punto Final , Proteínas de Fusión bcr-abl/genética , Trastornos Mieloproliferativos/tratamiento farmacológico , Humanos , Trastornos Mieloproliferativos/genética , Pronóstico
17.
Leuk Lymphoma ; 22 Suppl 1: 149-60, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8951786

RESUMEN

The therapeutic strategy in patients with Essential Thrombocythemia (ET) is a difficult balance between the prevention of bleeding and thrombotic complications and the risks of drug side effects and toxicity. Major bleeding is rare and seem to be related to higher platelet counts: therefore, a platelet count over 1500 x 10(9)/L is generally regarded as an indication for cytoreduction. Thrombotic complications include microvascular occlusive symptoms, which are reversible with low-dose aspirin, and large vessels thrombosis. The risk of major thrombosis is higher in ET patients aged more than 60 ys. and with previous occlusive event. In this high-risk group, the non-alkylating agent hydroxyurea (HU) significantly reduces the rate of vascular complications and has emerged as the treatment of choice. However, the long-term risk/benefit of HU remains disputed because its leukemogenic potential has not been ruled out. This holds also for other myelosuppressive agents, such as busulphan and pipobroman. Other drugs of particular interest for young patients include recombinant alpha-interferon (IFN) and Anagrelide. Both of them are effective in lowering platelet count, but their efficacy in reducing clinical complications remains to be demonstrated. However, both IFN and Anagrelide have shown to have frequent and clinically important side effects. Thus, further clinical studies are required to establish their role in the strategy of ET patient treatment.


Asunto(s)
Trombocitemia Esencial/terapia , Adulto , Anciano , Alquilantes/efectos adversos , Alquilantes/uso terapéutico , Anemia Megaloblástica/inducido químicamente , Arritmias Cardíacas/inducido químicamente , Enfermedades de la Médula Ósea/inducido químicamente , Busulfano/efectos adversos , Busulfano/uso terapéutico , Femenino , Hemorragia/epidemiología , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Hidroxiurea/efectos adversos , Hidroxiurea/uso terapéutico , Factores Inmunológicos/uso terapéutico , Incidencia , Interferón-alfa/uso terapéutico , Ataque Isquémico Transitorio/etiología , Leucemia/inducido químicamente , Masculino , Persona de Mediana Edad , Pipobromán/uso terapéutico , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Recuento de Plaquetas/efectos de los fármacos , Pronóstico , Quinazolinas/uso terapéutico , Factores de Riesgo , Trombocitemia Esencial/complicaciones , Trombocitemia Esencial/tratamiento farmacológico , Trombocitemia Esencial/epidemiología , Trombosis/epidemiología , Trombosis/etiología , Trombosis/prevención & control
18.
Neth J Med ; 54(2): 46-62, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10079679

RESUMEN

According to strict clinical, hematological and morphological criteria, the Philadelphia (Ph) chromosome negative chronic myeloproliferative disorders essential thrombocythemia (ET), polycythemia vera (PV), and agnogenic myeloid (megakaryocytic/granulocytic) metaplasia (AMM) or idiopathic myelofibrosis (IMF) are three distinct disease entities with regard to clinical manifestations, natural history and outcome in terms of life expectancy. As clonality studies have clearly demonstrated that fibroblast proliferation in AMM, as well as in many other conditions such as advanced stages of Ph(+)-essential thrombocythemia, Ph(+)-granulocytic leukemia, and Ph(-)-polycythemia vera, is polyclonal indicating that myelofibrosis is secondary to the megakaryocytic granulocytic metaplasia in these various conditions, AMM is illogically labeled as IMF. As abnormal megakaryocytic granulocytic metaplasia is the essential feature preceding the early prefibrotic stage of AMM, the term essential megakaryocytic granulocytic metaplasia (EMGM) can readily be used to characterize this condition more appropriately at the biological level. Clinical, hematological and morphological characteristics, in particular megakaryocytopoiesis and bone marrow cellularity, reveal diagnostic features, which enable a clear-cut distinction between ET, PV and EMGM or classical IMF. The characteristic increase and clustering of enlarged megakaryocytes with mature cytoplasm and multilobulated nuclei and their tendency to cluster in a normal or only slightly increased cellular bone marrow represent the hallmark of ET. The characteristic increase and clustering of enlarged mature and pleiomorphic megakaryocytes with multilobulated nuclei and proliferation of erythropoiesis in a moderate to marked hypercellular bone marrow with hyperplasia of dilated sinuses are the specific diagnostic features of untreated PV. EMGM, including the early prefibrotic stages as well as the various myelofibrotic stages of classical IMF appear to be a distinct neoplastic dual proliferation of abnormal megakaryopoiesis and granulopoiesis. The histopathology of the bone marrow in prefibrotic EMGM and in classical IMF is dominated by atypical, enlarged and immature megakaryocytes with cloud-like immature nuclei, which are not seen in ET and PV at diagnosis and during follow-up. Myelofibrosis in ET, PV and EMGM is graded into: no reticulin fibrosis (MF0), early reticulin fibrosis (MF1), advanced reticulin sclerosis with minor or moderate collagen fibrosis (MF2) and advanced collagen fibrosis with osteosclerosis (MF3). Myelofibrosis is not a feature of ET at diagnosis and during long-term follow-up. Myelofibrosis may be present in a minority of PV-patients at diagnosis and usually becomes apparent during long-term follow-up in the majority of PV-patients. Myelofibrosis secondary to the abnormal megakaryocytic and granulocytic myeloproliferation constitutes a prominent feature in the majority of EMGM/IMF at time of diagnosis and usually progresses more or less rapidly during the natural history of the disease. Life expectancy is normal in ET, normal during the 1st ten years and compromised during the 2nd ten years follow-up in PV, but significantly shortened in the prefibrotic stage of EMGM as well as in the various myelosclerotic stages of classical IMF. First line treatment options in prospective randomized clinical trials of newly diagnosed MPD-patients are control of platelet function with low-dose aspirin versus reduction of platelet count with anagrelide, interferon or hydroxyurea in ET; control of platelet and erythrocyte counts by interferon alone versus bloodletting plus hydroxyurea on indication in PV; interferon versus no treatment in the early stages of EMGM; a wait and see strategy in the fibrotic stages of EMGM or classical IMF with favorable prognostic factors, and bone marrow transplantation in classical IMF with poor prognostic factors at presentation or during short-term follow-up.


Asunto(s)
Trastornos Mieloproliferativos , Aspirina/uso terapéutico , Médula Ósea/patología , Trasplante de Médula Ósea , Diagnóstico Diferencial , Estudios de Seguimiento , Granulocitos/patología , Humanos , Interferones/uso terapéutico , Megacariocitos/patología , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/etiología , Trastornos Mieloproliferativos/terapia , Inhibidores de Agregación Plaquetaria/uso terapéutico , Policitemia Vera/diagnóstico , Policitemia Vera/etiología , Policitemia Vera/terapia , Mielofibrosis Primaria/diagnóstico , Mielofibrosis Primaria/etiología , Mielofibrosis Primaria/terapia , Pronóstico , Trombocitopenia/diagnóstico , Trombocitopenia/etiología , Trombocitopenia/terapia
20.
Leukemia ; 27(10): 2032-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23860450

RESUMEN

Reliable detection of JAK2-V617F is critical for accurate diagnosis of myeloproliferative neoplasms (MPNs); in addition, sensitive mutation-specific assays can be applied to monitor disease response. However, there has been no consistent approach to JAK2-V617F detection, with assays varying markedly in performance, affecting clinical utility. Therefore, we established a network of 12 laboratories from seven countries to systematically evaluate nine different DNA-based quantitative PCR (qPCR) assays, including those in widespread clinical use. Seven quality control rounds involving over 21,500 qPCR reactions were undertaken using centrally distributed cell line dilutions and plasmid controls. The two best-performing assays were tested on normal blood samples (n=100) to evaluate assay specificity, followed by analysis of serial samples from 28 patients transplanted for JAK2-V617F-positive disease. The most sensitive assay, which performed consistently across a range of qPCR platforms, predicted outcome following transplant, with the mutant allele detected a median of 22 weeks (range 6-85 weeks) before relapse. Four of seven patients achieved molecular remission following donor lymphocyte infusion, indicative of a graft vs MPN effect. This study has established a robust, reliable assay for sensitive JAK2-V617F detection, suitable for assessing response in clinical trials, predicting outcome and guiding management of patients undergoing allogeneic transplant.


Asunto(s)
Janus Quinasa 2/genética , Mutación/genética , Trastornos Mieloproliferativos/genética , Recurrencia Local de Neoplasia/diagnóstico , Neoplasia Residual/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto , Anciano , Análisis Citogenético , Europa (Continente) , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Trastornos Mieloproliferativos/terapia , Recurrencia Local de Neoplasia/genética , Neoplasia Residual/genética , Pronóstico , ARN Mensajero/genética , Inducción de Remisión , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante de Células Madre , Trasplante Homólogo , Adulto Joven
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