JAK2 46/1 haplotype is associated with JAK2 V617F--positive myeloproliferative neoplasms in Brazilian patients.

INTRODUCTION: This study aimed to verify the association between the JAK2 46/1 haplotype (V617F positive) and some hematological parameters in BCR-ABL-negative chronic myeloproliferative neoplasms (cMPNs) in our population. METHODS: The blood samples obtained from the patients with cMPN were genotyped for the JAK2 V617F mutation and JAK2 rs10974944 SNP screening using a PCR-RFLP assay. RESULTS: The JAK2 V617F mutation was detected in 80.15% of patients. The G variant of rs10974944 was more frequent in all MPNs, especially those that were JAK2 V617F positive, than in the control population. We also compared the 46/1 haplotype status in each MPN disease entity, polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PMF), and MPNu with controls. The G allele frequency relative to controls was significantly enriched in patients with PV and ET, but not in those with PMF and MPNu. PV and ET patients especially, all of whom had the JAK2 V617F mutation, showed significant excess of the G allele. The frequency of JAK2 V617F mutation was associated with elevated hematological parameters, but when we analyze the occurrence of the mutation and the presence of the G allele, just the high hemoglobin was significantly. CONCLUSION: In agreement with previous reports, JAK2 46/1 haplotype for JAK2 V617F was associated with cMPN positive in Brazilian patients.

Constitutive JunB expression, associated with the JAK2 V617F mutation, stimulates proliferation of the erythroid lineage.

The JAK2 V617F mutation, present in the majority of polycythemia vera (PV) patients, causes constitutive activation of JAK2 and seems to be responsible for the PV phenotype. However, the transcriptional changes triggered by the mutation have not yet been totally characterized. In this study, we performed a large-scale gene expression study using serial analysis of gene expression in bone marrow cells of a newly diagnosed PV patient harboring the JAK2 V617F mutation and in normal bone marrow cells of healthy donors. JUNB was one of the genes upregulated in PV, and we confirmed, by quantitative real-time PCR, an overexpression of JUNB in hematopoietic cells of other JAK2 V617F PV patients. Using Ba/F3-EPOR cell lines and primary human erythroblast cultures, we found that JUNB was transcriptionally induced after erythropoietin addition and that JAK2 V617F constitutively induced JunB protein expression. Furthermore, JUNB knockdown reduced not only the growth of Ba/F3 cells by inducing apoptosis, but also the clonogenic and proliferative potential of human erythroid progenitors. These results establish a role for JunB in normal erythropoiesis and indicate that JunB may play a major role in the development of JAK2 V617F myeloproliferative disorders.

Frontline therapy with early intensification and autologous stem cell transplantation versus conventional chemotherapy in unselected high-risk, aggressive non-Hodgkin's lymphoma patients: a prospective randomized GEMOH report.

This prospective multicenter randomized trial compares conventional with early intensification with high-dose sequential chemotherapy (HDS) and autologous stem cell transplantation (ASCT) as frontline therapy in high-risk non-Hodgkin lymphomas (NHL). Newly diagnosed patients with aggressive high-risk [intermediate-high (HI) and high-risk (HR)] NHL according to the international prognosis index (IPI) were randomized to receive 12-week VACOP-B (arm A, 27 patients) or 6-week VACOP-B followed by HDS and ASCT (arm B, 29 patients). Complete remission rate was 52% in arm A and 55% in B. Nine patients (16%) died early due to progression. According to intention-to-treat, with a median follow-up of 23 months, the 5-year actuarial overall survival, progression-free survival and disease-free survival in arms A and B were 47 and 40% (p = nonsignificant), 47 and 30% (p = nonsignificant), and 97 and 47% (p = 0.02), respectively. Abbreviated chemotherapy followed by intensification with HDS-ASCT does not seem to be superior to conventional chemotherapy in HI/HR aggressive NHL.

Cutaneous adverse reaction to 2-chlorodeoxyadenosine with histological flame figures in patients with chronic lymphocytic leukaemia.

INTRODUCTION: 2-Chlorodeoxyadenosine (cladribine or 2-CdA) is a purine analogue that has been used successfully in hairy cell leukaemia (HCL). Moreover, it has been increasingly used to treat chronic lymphoproliferative syndromes and paediatric acute myeloid leukaemia. Cutaneous side-effects associated with this drug have seldom been described in cases of HCL. PATIENTS AND METHODS: We describe three patients with chronic lymphocytic leukaemia that presented generalized skin eruptions after treatment with 2-CdA. RESULTS: All patients had advanced disease, receiving 2-CdA as a second or third line chemotherapy. Skin lesions were severe and chemotherapy had to be discontinued. Histological examination of skin biopsies showed an eosinophil-rich infiltrate with flame figures, similar to what is observed in Wells' syndrome (eosinophilic cellulitis). Corticosteroids were effective to control the eruptions. CONCLUSIONS: Cutaneous adverse reactions associated with 2-CdA have seldom been observed in the treatment of HCL. However, as this purine analogue has been used in more advanced cases these may be more frequent and severe. The pathophysiology of these lesions is unclear, but it is probably related to drug-induced change in T-cell imbalance in severely immunosuppressed patients.

Expression of p190 BCR-ABL fusion gene in a patient with chronic myeloid leukemia / Expressão do rearranjo gênico BCR-ABL com ponto de quebra na região menor do gene BCR em um paciente com leucemia mielóide crônica

A minority of chronic myeloid leukemia cases have breakpoints in the minor cluster region (m-bcr) of the BCR-ABL gene. We report on a patient with Ph-positive and m-bcr breakpoint at diagnosis. She was treated with hydroxyurea and interferon-alpha. Two years later, she developed a lymphoid blast crisis and died shortly after. We discuss herein the different forms of the BCR-ABL oncogene, its products, and the possible influence of them on the clinical outcome of patients with the disease

A leucemia mielóide crônica (LMC) é umadoença mieloproliferativa clonal e caracteriza-se pela presença da translocaçãocromossômica entre os braços longos doscromossomos 9 e 22, o denominadocromossomo Ph. Esta translocação determinaa fusão dos genes BCR e ABL. Os diferentespontos de quebra no gene BCR determinama síntese de proteínas com diferentespesos moleculares pelo gene BCR-ABL.Nós relatamos o caso de uma paciente portadorade LMC com ponto de quebracromossômico na região menor do geneBCR. Foi tratada com hidroxiuréia einterferon alfa. Dois anos após o diagnósticodesenvolveu crise blástica linfóide e evoluiurapidamente para o óbito. Nós discutimos nestaapresentação as diferentes formas do gene BCR-ABL eseus produtos e a possível influência dos mesmos naevolução clínica dos pacientes com a doença.(AU)76.

Apoptosis-regulating proteins and prognosis in diffuse large B cell non-Hodgkin's lymphomas.

We evaluated the expression of apoptosis-regulating proteins (p53, Bcl-2, Bax, Bak and Mcl-1) in paraffin-embedded tissues of 33 patients with diffuse large B cell non-Hodgkin's lymphoma, and assessed the relationship of these proteins to clinical outcome and response to chemotherapy. Our results showed that p53 expression was an independent immunohistochemical parameter related to a poor prognosis in these lymphomas. Bcl-2, Bax, Bak and Mcl-1 proteins, though highly expressed in almost all cases were not associated with prognosis or response to treatment.

p53, Mdm2, and c-Myc overexpression is associated with a poor prognosis in aggressive non-Hodgkin's lymphomas.

The expression of p53, p21/WAF-1, Mdm2, c-Myc, and proliferating cell nuclear antigen (PCNA) proteins was examined by the immunohistochemistry of paraffin-embedded tissues of 62 patients with aggressive non-Hodgkin's lymphomas (NHL) and correlated to clinical data. Expression of p53, p21/WAF-1, Mdm2, and c-Myc protein was observed in 17 out of 62 cases (30%), 25 out of 60 (42%), 13 out of 44 (30%), and 39 out of 51 (76.5%), respectively. The p53+/p21WAF-1 phenotype, which is more frequently found in p53 mutations, was associated with a worse overall survival (P = 0.04) and with a lower rate of complete response (CR) (PF = 0.01). p53 and c-Myc negative expression was related to a better response to chemotherapy (PF = 0.005 and 0.035, respectively). The expression of p53, c-Myc, and Mdm2 was related to a shortened overall survival (P < 0.001, 0.05, and 0.037, respectively), suggesting that the expression of these proteins could be associated with a poor outcome in these patients.

Conventional chemotherapy for acute myeloid leukemia: a Brazilian experience.

CONTEXT: Young patients affected by acute myeloid leukemia (AML) achieve complete remission (CR) using conventional chemotherapy in about 55-85%. However, 30% of patients fail to achieve CR and the remission duration is often only about 12 months. More intensive treatment after CR seems to be necessary in order to maintain CR and obtain a definitive cure. In Brazil, few reports have been published on this important subject. OBJECTIVE: The aim of this study was to describe a Brazilian experience in the treatment of "de novo" acute myeloid leukemia (AML) in younger adult patients (age < 60 years). DESIGN: Retrospective analysis. SETTING: University Hospital, Hematology and Hemotherapy Center, State University of Campinas, Brazil. PARTICIPANTS: Newly diagnosed cases of "de novo" AML in the period from January 1994 to December 1998 were evaluated retrospectively, in relation to response to treatment, overall survival (OS) and disease free survival (DFS). Cases with acute promyelocytic leukemia (APL) were also included in this analysis. RESULTS: On the basis of an intention to treat, 78 cases of AML, including 17 cases of APL, were evaluated. The overall median follow-up was 272 days. The complete remission (CR) rate was 63.6% in the AML group (excluding APL) and 78% in the APL group. The 5-year estimated disease-free survival (DFS) was 80% for the APL group and 34% for the AML group (P = 0.02). The 5-year estimated overall survival (OS) was 52% for the APL group and 20.5% for the AML group, respectively (P = NS). Relapse was observed in 12/39 (30.7%) patients with AML and 1/11 (9%) with APL. CONCLUSIONS: These results are similar to those reported in the literature. However, relapse and mortality rates remain high, and a search for more aggressive strategies in order to prevent relapse is recommended.