Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 35
Filtrer
1.
Surg Oncol ; 20(3): 155-61, 2011 Sep.
Article de Anglais | MEDLINE | ID: mdl-20739177

RÉSUMÉ

In this essay we set out clinical communication challenges in surgical oncology. We draw directly on relevant examples where they are available. Otherwise, we refer to the more generic surgical and medical literature. We offer 'macro' and 'micro' perspectives on clinical communication. That is, exploring communication challenges at the level of the organization and between individuals, doctors and patients and interprofessionally across different settings. Training content and methods are reported that address the complex communication challenges associated with surgical oncology. Innovations in simulation-based education offer exciting new opportunities for formative and summative assessment. We outline limitations of the essay and finally propose the content of a surgical oncology communication program.


Sujet(s)
Compétence clinique , Communication , Comportement coopératif , Enseignement spécialisé en médecine/méthodes , Chirurgie générale/enseignement et éducation , Oncologie médicale/enseignement et éducation , Tumeurs/chirurgie , Humains , Relations médecin-patient
2.
Braz. j. med. biol. res ; 40(12): 1623-1629, Dec. 2007. tab
Article de Anglais | LILACS | ID: lil-466736

RÉSUMÉ

Allogeneic stem cell transplantation has been increasingly performed for a variety of hematologic diseases. Clinically significant acute graft-versus-host disease (GVHD) occurs in 9 to 50 percent of patients who receive allogeneic grafts, resulting in high morbidity and mortality. There is no standard therapy for patients with acute GVHD who do not respond to steroids. Studies have shown a possible benefit of anti-TNF-a (infliximab)for the treatment of acute GVHD. We report here on the outcomes of 10 recipients of related or unrelated stem cell transplants who received 10 mg/kg infliximab, iv, once weekly for a median of 3.5 doses (range: 1-6) for the treatment of severe acute GVHD and who were not responsive to standard therapy. All patients had acute GVHD grades II to IV (II = 2, III = 3, IV = 5). Overall, 9 patients responded and 1 patient had progressive disease. Among the responders, 3 had complete responses and 6 partial responses. All patients with cutaneous or gastrointestinal involvement responded, while only 2 of 6 patients with liver disease showed any response. None of the 10 patients had any kind of immediate toxicity. Four patients died, all of them with sepsis. Six patients are still alive after a median follow-up time of 544 days (92-600) after transplantation. Considering the severity of the cases and the bad prognosis associated with advanced acute GVHD, we find our results encouraging. Anti-TNF-a seems to be a useful agent for the treatment of acute GVHD.


Sujet(s)
Adolescent , Adulte , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Mâle , Anticorps monoclonaux/usage thérapeutique , Glucocorticoïdes/usage thérapeutique , Maladie du greffon contre l'hôte/traitement médicamenteux , Transplantation de cellules souches hématopoïétiques/effets indésirables , Méthylprednisolone/usage thérapeutique , Facteur de nécrose tumorale alpha/antagonistes et inhibiteurs , Maladie aigüe , Association de médicaments , Études de suivi , Leucémies/mortalité , Leucémies/chirurgie , Indice de gravité de la maladie , Résultat thérapeutique
3.
Bioorg Med Chem Lett ; 17(22): 6138-41, 2007 Nov 15.
Article de Anglais | MEDLINE | ID: mdl-17904844

RÉSUMÉ

The structure-activity relationships of new quinoline based compounds were investigated. Quinoline-5,8-dione and styrylquinoline scaffolds were used for the design of potentially active compounds. The novel analogues had comparable antiproliferative activity to cisplatin when evaluated in a bioassay against the P388 leukemia cell line. However, these compounds appeared far less efficient against SK-N-MC neuroepithelioma cells. Analogues without the 5,8-dione structure but containing the 8-carboxylic acid group were also found to induce antiproliferative activity. Hydrophobicity as measured by HPLC did not correlate with antiproliferative activity.


Sujet(s)
Antinéoplasiques/pharmacologie , Acides carboxyliques/pharmacologie , Prolifération cellulaire/effets des médicaments et des substances chimiques , Quinoléines/pharmacologie , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/composition chimique , Acides carboxyliques/synthèse chimique , Acides carboxyliques/composition chimique , Lignée cellulaire tumorale , Tests de criblage d'agents antitumoraux , Humains , Souris , Structure moléculaire , Quinoléines/synthèse chimique , Quinoléines/composition chimique , Relation structure-activité
4.
Braz J Med Biol Res ; 40(12): 1623-9, 2007 Dec.
Article de Anglais | MEDLINE | ID: mdl-17713663

RÉSUMÉ

Allogeneic stem cell transplantation has been increasingly performed for a variety of hematologic diseases. Clinically significant acute graft-versus-host disease (GVHD) occurs in 9 to 50% of patients who receive allogeneic grafts, resulting in high morbidity and mortality. There is no standard therapy for patients with acute GVHD who do not respond to steroids. Studies have shown a possible benefit of anti-TNF-a (infliximab)for the treatment of acute GVHD. We report here on the outcomes of 10 recipients of related or unrelated stem cell transplants who received 10 mg/kg infliximab, iv, once weekly for a median of 3.5 doses (range: 1-6) for the treatment of severe acute GVHD and who were not responsive to standard therapy. All patients had acute GVHD grades II to IV (II = 2, III = 3, IV = 5). Overall, 9 patients responded and 1 patient had progressive disease. Among the responders, 3 had complete responses and 6 partial responses. All patients with cutaneous or gastrointestinal involvement responded, while only 2 of 6 patients with liver disease showed any response. None of the 10 patients had any kind of immediate toxicity. Four patients died, all of them with sepsis. Six patients are still alive after a median follow-up time of 544 days (92-600) after transplantation. Considering the severity of the cases and the bad prognosis associated with advanced acute GVHD, we find our results encouraging. Anti-TNF-a seems to be a useful agent for the treatment of acute GVHD.


Sujet(s)
Anticorps monoclonaux/usage thérapeutique , Glucocorticoïdes/usage thérapeutique , Maladie du greffon contre l'hôte/traitement médicamenteux , Transplantation de cellules souches hématopoïétiques/effets indésirables , Méthylprednisolone/usage thérapeutique , Facteur de nécrose tumorale alpha/antagonistes et inhibiteurs , Maladie aigüe , Adolescent , Adulte , Enfant , Enfant d'âge préscolaire , Association de médicaments , Femelle , Études de suivi , Humains , Infliximab , Leucémies/mortalité , Leucémies/chirurgie , Mâle , Indice de gravité de la maladie , Résultat thérapeutique
5.
Transplant Proc ; 36(4): 814-5, 2004 May.
Article de Anglais | MEDLINE | ID: mdl-15194280

RÉSUMÉ

Striking progress has been observed in the number of volunteer donors for hematopoietic stem cell transplantation in the last years in Brazil. By the end of 1998, the number of donors barely reached 4200 but it has grown progressively. It was close to 48,000 by the end of May 1993. It is possible to notice a steady increase from the first (1993 to 2000) to the last years (2001 to 2003). The regulation of each procedure by the Brazilian Health System, with the collaboration of the Hematology Societies, was essential for the success of Redome and for the stem cell transplantation program in Brazil. However, when analyzing these results some problems were detected: 95% of Redome donors come from the south and southeastern regions of the country, while few donors are from the north, northeast, and central parts of Brazil. The different miscegenation of races in different regions and states of Brazil makes this an important issue: to represent the whole Brazilian population, Redome must improve the donor search in such places. It also became clear that several other centers involved in unrelated hematopoietic transplantation must be accredited to avoid a long line of patients with compatible donors a waiting transplantation.


Sujet(s)
Moelle osseuse , Expérimentation humaine/statistiques et données numériques , Enregistrements , Donneurs de tissus/statistiques et données numériques , Brésil , Humains
6.
Acta Pol Pharm ; 61 Suppl: 3-4, 2004 Dec.
Article de Anglais | MEDLINE | ID: mdl-15909921

RÉSUMÉ

In our work, leading to new styrylquinoline and styrylquinazoline inhibitors of HIV integrase, we analyzed virtual combinatorial library that includes these compounds. Using this method we were able to find interesting synthetic targets. We optimized synthetic procedure yielding such compounds and obtained a couple of new analogues. Their activity will be evaluated in the near future.


Sujet(s)
Inhibiteurs de l'intégrase du VIH/synthèse chimique , Quinazolines/synthèse chimique , Quinazolines/pharmacologie , Quinoléines/synthèse chimique , Quinoléines/pharmacologie , Techniques de chimie combinatoire , Conception de médicament , Inhibiteurs de l'intégrase du VIH/pharmacologie , Indicateurs et réactifs
7.
Cytotherapy ; 5(4): 336-45, 2003.
Article de Anglais | MEDLINE | ID: mdl-12944240

RÉSUMÉ

BACKGROUND: PBSC transplant provides 10 times more T cells than BMT However, the incidence and severity of acute GvHD is similar among recipients of both types of transplants. Studies in mouse models suggest that the similar clinical outcome in BMT and PBSCT is due to differences in the lymphokine profiles. METHODS: PBMC, PBMC from G-CSF mobilized donors (G-PBMC)and BM mononuclear cells (BM-MC) were analyzed by flow cytometry and ELISA to detect gamma-IFN and IL-4 production. Hematoxylin and eosin staining was used to identify morphology and annexin/propidium-iodide was used for apoptosis assays. RESULTS: We show decreased production of gamma-interferon (85%) and IL-4 (60%) in G-PBMC when compared with either PBMC or BM-MCT cells on ex vivo assays. Surprisingly, 85% of fresh G-PBMC is composed of low-density granulocytes (LDG), which undergo apoptosis after 48 h in culture. At this same time, gamma-IFN production from G-PBMC T cell was reverted. In vitro, G-CSF converts granulocytes into LDGs, able to inhibit T-cell function by H2O2 production, and not through immune-deviation towards a Th2-type phenotype. DISCUSSION: We show that the estimated numbers of Th1 and Th2 cells infused in BMT and PBSCT do not differ significantly. These findings are discussed with reference to the relatively low incidence of acute GvHD in PBSCT shown in the literature. We suggest that these results might depend on the high number of granulocytes and progenitors infused. The potential use of granulocytes as immunosupressive short-term therapy is now being investigated by our group using a mouse experimental model.


Sujet(s)
Granulocytes/physiologie , Transplantation de cellules souches de sang périphérique , Lymphocytes T/physiologie , 12-Myristate-13-acétate de phorbol/analogues et dérivés , Annexine A5/analyse , Antigènes CD/analyse , Apoptose/physiologie , Cellules de la moelle osseuse/cytologie , Cellules de la moelle osseuse/effets des médicaments et des substances chimiques , Cellules de la moelle osseuse/physiologie , Transplantation de moelle osseuse , Antigènes CD3/analyse , Catalase/pharmacologie , Numération cellulaire , Cytométrie en flux , Facteur de stimulation des colonies de granulocytes/pharmacologie , Granulocytes/cytologie , Granulocytes/effets des médicaments et des substances chimiques , Mobilisation de cellules souches hématopoïétiques , Transplantation de cellules souches hématopoïétiques , Humains , Peroxyde d'hydrogène/métabolisme , Interféron gamma/analyse , Interleukine-4/analyse , Ionomycine/pharmacologie , Agranulocytes/cytologie , Agranulocytes/effets des médicaments et des substances chimiques , Agranulocytes/physiologie , Antigènes CD43 , Test de culture lymphocytaire mixte , Activation des neutrophiles/effets des médicaments et des substances chimiques , Activation des neutrophiles/physiologie , Sialoglycoprotéines/analyse , Lymphocytes T/composition chimique , Lymphocytes T/effets des médicaments et des substances chimiques , 12-Myristate-13-acétate de phorbol/pharmacologie , Facteurs temps
8.
Bone Marrow Transplant ; 29(9): 745-51, 2002 May.
Article de Anglais | MEDLINE | ID: mdl-12040471

RÉSUMÉ

In order to assess the effect of delaying G-CSF administration after autologous peripheral blood progenitor cell (PBPC) transplantation on the duration of neutropenia, 87 patients were randomized to receive G-CSF 5 microg/kg/day starting on day +1 (n = 45) or +5 (n = 42) following PBPC transplantation, until recovery of the neutrophils. The duration of neutropenia (<0.5 x 10(9)/l) was shorter in the day +1 group (7 vs 8 days; P = 0.02), especially in patients receiving melphalan 200 mg/m(2) and CD34(+) cell doses >3.0 x 10(6)/kg. These patients had a later onset of neutropenia after transplant. There were no differences in time to neutrophil and platelet engraftment, or in the incidence of fever and documentation of infection. Although the duration of antibiotic therapy (7 vs 10.5 days; P = 0.01) and time to hospital discharge (13 vs 15 days; P = 0.02) were shorter in the day +1 group, these differences could not be predicted by the day of G-CSF initiation in multivariate analysis. Starting G-CSF on day +1 does not result in faster neutrophil engraftment but in later onset and consequently, slightly shorter duration of neutropenia in patients who receive melphalan 200 mg/m(2) and CD34(+) cell doses >3.0 x 10(6)/kg.


Sujet(s)
Facteur de stimulation des colonies de granulocytes/administration et posologie , Transplantation de cellules souches de sang périphérique/méthodes , Adolescent , Adulte , Sujet âgé , Calendrier d'administration des médicaments , Femelle , Fièvre/étiologie , Fièvre/prévention et contrôle , Survie du greffon/effets des médicaments et des substances chimiques , Facteur de stimulation des colonies de granulocytes/pharmacologie , Tumeurs hématologiques/complications , Tumeurs hématologiques/thérapie , Hématopoïèse/effets des médicaments et des substances chimiques , Humains , Mâle , Adulte d'âge moyen , Neutropénie/prévention et contrôle , Transplantation de cellules souches de sang périphérique/effets indésirables , Études prospectives , Transplantation autologue/effets indésirables , Transplantation autologue/méthodes , Résultat thérapeutique
9.
Bone Marrow Transplant ; 28(3): 311-2, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11536001

RÉSUMÉ

We report a case of capillary leak syndrome in a 37-year-old female PBPC donor who received G-CSF 900 microg/day for 4 days and underwent leukapheresis. This lady had remained well and stable despite marked leukocytosis during G-CSF treatment, but developed hypotension during leukapheresis, quickly followed by hypoxemia, ascites, pericardial and pleural effusion, shock, edema, neurologic changes and hepatocellular injury. Upon G-CSF withdrawal, dopamine and crystalloid infusion, methylprednisolone treatment and suspension of apheresis, the clinical situation fully reversed. We hypothesize that leukapheresis, in the presence of marked leukocytosis and high doses of G-CSF, may have triggered neutrophil activation and the release of inflammatory mediators, resulting in tissue damage and systemic manifestations of increased capillary permeability.


Sujet(s)
Donneurs de sang , Syndrome de fuite capillaire/étiologie , Mobilisation de cellules souches hématopoïétiques/effets indésirables , Adulte , Femelle , Facteur de stimulation des colonies de granulocytes/administration et posologie , Facteur de stimulation des colonies de granulocytes/toxicité , Transplantation de cellules souches hématopoïétiques , Humains , Leucaphérèse , Hyperleucocytose/induit chimiquement , Hyperleucocytose/complications , Transplantation homologue
10.
Bone Marrow Transplant ; 27(1): 73-8, 2001 Jan.
Article de Anglais | MEDLINE | ID: mdl-11244440

RÉSUMÉ

We investigated the use of 'prophylactic' donor lymphocyte infusions (DLI) containing 1 x 107 CD3+ cells, given at 30, 60 and 90 days post-allogeneic blood and marrow transplantation (BMT), following conditioning with fludarabine 30 mg/m(2)/4 days and melphalan 70 mg/m(2)/2 days. GVHD prophylaxis consisted of cyclosporin A (CsA) 2 mg/kg daily with early tapering by day 60. Our goals were the rapid achievement of chimerism and disease control, providing an immunological platform for DLIs to treat refractory patients with hematological malignancies. Twelve heavily pre-treated patients with life expectancy less than 6 months were studied; none were in remission. Diagnoses were AML (n = 4), MDS (n = 1), ALL (n = 3), CML (n = 3) and multiple myeloma (n = 1). Response rate was 75%. Three patients are alive at a median of 450 days (range, 450-540). Two patients are in remission of CML in blast crisis and AML for more than 14 months. Median survival is 116 days (range, 25-648). Six patients received 12 DLIs; three patients developed acute GVHD after the first infusion and were excluded from further DLIs, but no GVHD occurred among patients receiving subsequent DLIs. One patient with CML in blast crisis went into CR after the first DLI. The overall incidence of acute GVHD was 70%. Primary causes of death were infections (n = 3), acute GVHD (n = 3), chronic GVHD (n = 1) and disease relapse (n = 2). We observed high response and chimerism rates at the expense of an excessive incidence of GVHD. DLI given at day +30 post BMT caused GVHD in 50% of the patients, and its role in this setting remains unclear.


Sujet(s)
Tumeurs hématologiques/thérapie , Transplantation de cellules souches hématopoïétiques/effets indésirables , Transfusion de lymphocytes/normes , Adolescent , Adulte , Antinéoplasiques/usage thérapeutique , Antinéoplasiques/toxicité , Cause de décès , Enfant , Femelle , Maladie du greffon contre l'hôte/étiologie , Maladie du greffon contre l'hôte/mortalité , Réaction du greffon contre la leucémie , Tumeurs hématologiques/complications , Tumeurs hématologiques/mortalité , Transplantation de cellules souches hématopoïétiques/mortalité , Humains , Transfusion de lymphocytes/effets indésirables , Transfusion de lymphocytes/mortalité , Mâle , Adulte d'âge moyen , Pronostic , Induction de rémission/méthodes , Prévention secondaire , Chimère obtenue par transplantation
12.
Leuk Res ; 24(10): 839-48, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-10996202

RÉSUMÉ

Several studies have demonstrated the prognostic value of cytogenetic analysis in MDS both for survival and progression to AML. However it is unknown which are the numerical or structural abnormalities required for leukemic transformation. In this report we studied clinically and cytogenetically 127 patients: 125 with primary MDS and two with AML with a previous history of MDS. Thirty-one patients (24%) showed evolution of the disease during the follow-up study. Chromosomal abnormalities found at diagnosis in patients that progressed toward AML included: del(5)(q15), +6, del(6)(q21), t(5;8)(q32;q22),-7, del(7)(q22), der(7)t(1;7)(q10;p10), t(7;11)(p15;p15), +8, del(11)(q23), del(12p), del(3)(q21), del(20)(q12) and complex karyotypes. Eight of these patients were studied cytogenetically during transformation and showed acquisition of chromosomal alterations involving dup(1q), +8, del(11)(q23), and translocations between chromosomes 1 and 8 or 7 and 17. In addition we also observed gain of ploidy and monosomy 21. These results suggest that chromosomal alterations during evolution of the disease include special chromosome gains or abnormalities of chromosomes 1, 7, 8, 11 and 17 with involvement of ETV-1, Hox-A9, Pax 4, MLL genes besides a putative gene mapped at 17q25. We also applied the International Prognostic Scoring System (IPSS) to 114 patients, excluding those submitted to allogeneic bone marrow transplant. Our patients were classified into four distinct risk groups. The analysis of risk groups presented by 27 patients who showed evolution of the disease revealed 18 at the high risk group and four at the intermediate-2 group. From the intermediate-1 risk group only five patients showed evolution of the disease. Three of these patients evolved from RA to RAEB with gain of a del(11)(q23) or an expansion of a del(12)(p12) clone. Our results suggest that some chromosomal alterations are responsible for each step in the evolution of the disease. As the pathway of evolution is not unique it has been very difficult to define what genetic alteration comes first. However from several results in the literature and our own, it seems that some chromosomal alterations may predict the evolution of the disease and are correlated with short survival, as for example the trisomy of chromosome 8, and might be incorporated in the high risk group in the IPSS. This score system has been proved to be useful for predicting survival and evolution from MDS to AML.


Sujet(s)
Aberrations des chromosomes , Leucémie aigüe myéloïde/génétique , Syndromes myélodysplasiques/génétique , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Caryotypage , Mâle , Adulte d'âge moyen
13.
Leuk Lymphoma ; 37(1-2): 205-11, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10721788

RÉSUMÉ

Single-step Multiplex RT-PCR was used as a rapid and highly sensitive method for screening patients with myeloproliferative conditions and ALL for the presence of underlying BCR-ABL gene fusions. Positive and negative results obtained with the multiplex assay were subsequently confirmed by nested PCR. We studied 21 patients for detecting the presence of b3a2, b2a2 and e1a2 BCR-ABL transcripts at diagnosis and following treatment with different therapeutical procedures. These studies allowed the molecular characterisation of patients with different haematological disorders and for demonstrating BCR-ABL transcripts in Ph-CML. In a Ph+ CML patient, a switch of isoforms was detected after bone marrow transplantation and infusion with donor lymphocytes, implying substitution of e1a2 for b3a2 coexisting with a myeloid/lymphoid biphenotypic profile. In ALL, one Ph+ patient showed coexpression of e1a2 and b2a2 at diagnosis followed by persistence of e1a2 after bone marrow transplantation. Our results were compared to previous findings in the literature on molecular diagnosis of leukaemias.


Sujet(s)
Protéines de fusion bcr-abl/métabolisme , Tumeurs hématologiques/métabolisme , ADN complémentaire , Protéines de fusion bcr-abl/génétique , Tumeurs hématologiques/génétique , Humains , Leucémie myéloïde chronique BCR-ABL positive/génétique , Leucémie myéloïde chronique BCR-ABL positive/métabolisme , Réaction de polymérisation en chaîne , Leucémie-lymphome lymphoblastique à précurseurs B et T/génétique , Leucémie-lymphome lymphoblastique à précurseurs B et T/métabolisme , ARN/analyse
14.
Cancer Genet Cytogenet ; 117(2): 104-7, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10704678

RÉSUMÉ

The development of acute megakaryoblastic leukemia (ANLL-M7) following myelodysplastic syndrome (MDS) has been described only in a few reports, and the mutations necessary for this transformation are still unknown. In this study, we describe a case of ANLL-M7 with a previous history of MDS presenting a complex karyotype 46,XX, t(4;11)(q21;q23),del(5)(q13q33),t(12;13)(p13;q21) and N-RAS point mutation. During MDS, the patient showed a hypercellular myelogram with dysplasia of the three myeloid lineages and the clinical symptoms characteristic of the 5q- syndrome. During the follow-up, we observed the appearance of two additional subclones, one with an isochromosome 17q and another with polyploidy. The presence of an isochromosome 17q in one subclone and polyploidy in another is probably due to the genetic instability generated by the malignant transformation.


Sujet(s)
Chromosomes humains de la paire 13 , Gènes ras , Leucémie aigüe mégacaryoblastique/génétique , Aberrations des chromosomes , Zébrage chromosomique , Codon , Issue fatale , Femelle , Humains , Hybridation fluorescente in situ , Caryotypage , Leucémie aigüe mégacaryoblastique/étiologie , Leucémie aigüe mégacaryoblastique/thérapie , Adulte d'âge moyen , Syndromes myélodysplasiques/complications , Syndromes myélodysplasiques/génétique , Mutation ponctuelle , Réaction de polymérisation en chaîne
16.
Leuk Res ; 23(2): 185-90, 1999 Feb.
Article de Anglais | MEDLINE | ID: mdl-10071134

RÉSUMÉ

Polymerase chain reaction (PCR) is a powerful and rapid method for specifically detecting BCR-ABL rearrangement by amplification of the complementary DNA (cDNA) produced by reverse transcription of BCR-ABL mRNA. We studied 29 patients for detecting the presence of BCR-ABL transcripts before and after bone marrow transplantation (BMT). Our sample was composed of two different groups of patients: one group (n = 18) was studied by serial follow-ups before and after BMT; a second group (n = 11) was studied several years after BMT. Detection of BCR-ABL was carried out with different primer sets at different periods of the clinical outcome of chronic myeloid leukaemia (CML). A comparison of PCR data and clinical-haematological conditions showed clear differences between patients. In the first group, eight patients showed a positive correlation between a favourable clinical outcome and molecular remission. Conversely, in the second group, six patients were BCR-ABL positive between 20 and 117 months after BMT, while only two of these patients showed signs of clinical relapse. Among all patients whose isoforms were known at some time during the course of CML, the more frequent isoform was b3a2. These results were compared to previous findings in the literature on diagnosis, outcome and prognosis of CML.


Sujet(s)
Protéines de fusion bcr-abl/génétique , Leucémie myéloïde chronique BCR-ABL positive/génétique , Réaction de polymérisation en chaîne , ARN messager/analyse , Transplantation de moelle osseuse , Humains
17.
Leuk Res ; 22(2): 125-34, 1998 Feb.
Article de Anglais | MEDLINE | ID: mdl-9593469

RÉSUMÉ

A cytogenetic and N-ras point mutation study was done in patients with primary myelodysplastic syndrome (MDS) from Rio de Janeiro, Brazil, in order to evaluate the progression of preleukemic states to overt leukemia. Cytogenetic analysis was performed in 50 patients with MDS and clonal chromosomal abnormalities were detected in 19 (38%) of them. Patients with refractory anemia (RA) or with ringed sideroblasts (RARS) presented normal karyotypes or single abnormalities as del(5q) or -Y, while patients in more advanced states as RA with excess of blasts (RAEB), RAEB in transformation (RAEB-t) and chronic myelomonocytic leukemia (CMML) showed complex karyotypes and single abnormalities involving chromosomes 7 or 8, which were related to poor prognosis and elevated risk of transformation to acute myeloid leukemia (AML). The frequency of ras activation was studied in these 50 patients with MDS. Samples of bone marrow were screened for oncogenic point mutations by DNA amplification followed by oligonucleotide hybridization analysis (PCR-ASO) at codon 12 of N-ras proto-oncogene. We detected N-ras point mutations in 21 patients (42%). Progression from MDS to AML was observed in 9 patients (18%). The correlation analysis between N-ras point mutations and specific chromosomal abnormalities indicated that although mutated N-ras was found in cells with del(5q) and monosomy 7, cells with those abnormalities and normal N-ras were also identified. Otherwise trisomy of chromosome 8 showed a correlation with N-ras point mutations and in all cases, patients showed progression of MDS to AML during the follow-up study. MDS comprises a heterogeneous group of hematopoietic disorders and probably several steps are implicated in the evolution to AML. In this work we suggest that one possible pathway of leukemogenesis in MDS includes N-ras point mutations in association with trisomy of chromosome 8.


Sujet(s)
Aberrations des chromosomes , Maladies chromosomiques , Gènes ras , Syndromes myélodysplasiques/génétique , Mutation ponctuelle , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Transformation cellulaire néoplasique/génétique , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Adulte d'âge moyen , Proto-oncogène Mas
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE