The hematology journal : the official journal of the European Haematology Association最新文献

The current study was aimed at investigating platelet function in MDS and its clinical significance. There were 23 patients with untreated MDS at presentation, including refractory anemia (RA), RA with ringed sideroblasts, RA and excess blasts and chronic myelomonocytic leukemia RAEBt. The mean platelet count was 167.9 x 109/L. Patients with a platelet count less than 70 x 109/l were excluded. The mean bleeding time (BT) was 2.7 min. Only four MDS patients had BT longer than the normal 1-4 min range. Platelet aggregation (PA) was studied with epinephrine (Epi), ADP, arachidonic acid (AA), ristocetin and collagen. Overall, 16 (70%) patients had PA abnormality, 65% had impaired Epi-induced PA, 57% demonstrated reduced ADP-induced PA. AA, ristocetin and collagen was decreased PA in 48, 22 and 17%, respectively. Five patients (22%) demonstrated spontaneous PA. Only seven patients (30%) were found to have normal PA with all five inducers. Six (26%) patients had spontaneous mild bleeding and all six bleeding MDS patients demonstrated at least one abnormal platelet function. The only bleeding patient with all five PA tests normal demonstrated prolonged BT. In the present study of 23 newly diagnosed MDS patients, PA abnormalities were relatively common, the BTs were usually normal, and bleedings were relatively uncommon and mild at platelet count between 70 and 397 x 109/l.

High-dose chemotherapy and autologous marrow or peripheral stem cell support offers the best chance of cure in some subgroups of patients with non-Hodgkin's lymphoma (NHL). Less is known about the role of a second course of myeloablative chemotherapy in patients who relapse after a first autologous transplant. The aim of this retrospective study was to evaluate the disease outcome, morbidity and mortality associated with second autologous transplantation in patients with NHL. Between 1985 and 2001, 225 patients who had received autologous transplantation for NHL in two institutions in Lyon relapsed. Of these 225 patients 18 underwent a second autologous transplantation. The median age at second transplant was 41 years. There were six indolent lymphomas and 12 aggressive lymphomas. The median follow-up from the second transplant was 42 months. The OS rate at 2 and 5 years were 58 and 27%, respectively. The PFS rate at 2 and 5 years was 36%. Five patients are alive without disease 20 to 100 months after the second transplant. Seven patients died of disease recurrence. Four (22%) toxic deaths occurred: one of pulmonary fibrosis, one of fungal infection and cardiac failure and two of acute leukaemia. A minority of patients with NHL recurrence after a first transplant can be cured by a second course of myeloablative chemotherapy at the cost however of high-risk toxic death.

DNAzymes are nucleic acid enzymes that can recognise specific RNA substrate via Watson-Crick base pairing and cleave it with multiple turnovers. We have designed and examined the effects of DNAzymes targeting the PML/RARalpha fusion gene in acute promyelocytic leukaemia (APL). The DNAzymes (DZ1 and DZ3) were designed to cleave the PML/RARalpha transcript at the GC nucleotides at the fusion point and three nucleotides upstream of that respectively. Disabled DNAzymes were synthesised and used as controls. Cell-free cleavage reactions were performed on total RNA from NB4 cell line and PML/RARalpha and RARalpha-amplified RNA fragments (aRNA). Postcleavage examination showed that DZ1 and DZ3 cleave PML/RARalpha efficiently and specifically. NB4 APL cells transfected with DZ1 or DZ3 showed a significant suppression of PML/RARalpha protein expression. These DNAzymes also inhibited the proliferation of NB4 cells, reduced the viability rate, and induced apoptosis in these cells. The disabled DNAzymes showed no effect on NB4 cells. The two DNAzymes did not produce any significant effect on K562 cells, which were used as control cells. DNAzymes are more resistant to serum than ribozymes. These data show that targeting the PML/RARalpha fusion gene with DNAzymes can induce apoptosis in APL cells and may have a role in the treatment of APL. They also show DNAzymes are promising tools for targeting specific genes in leukaemia.

Iron overload is a serious condition, which may lead to irreversible organ damage. The risk of iron accumulation in pyruvate kinase deficiency (PKD) has traditionally been regarded as low, but recent evidence has questioned this notion. We here present a case of a young PKD patient showing evidence of asymptomatic iron accumulation measured as liver iron concentration (LIC) obtained noninvasively by magnetic resonance imaging. The iron overload was not related to blood transfusions, but rather secondary to concomitant risk factors leading to increased intestinal iron absorption, such as chronic hemolysis and splenectomy. The iron status of PKD patients, preferably assessed by LIC measurements, should therefore be evaluated regularly also in asymptomatic patients. This evaluation should start already at a young age, in order to initiate iron chelation before the development of iron-induced organ damage.

The role of Daxx, in particular its ability to promote or hinder proliferation, still remains controversial. In order to elucidate the functional relevance of Daxx in malignant myelocytes, the erythroleukemia cell line HEL was stably transfected with a Daxx-expressing vector or with the respective Daxx-negative control vector. Assessing the molecular consequences of ectopic Daxx-expression, we present evidence that Daxx downregulates p53. Moreover, we demonstrate that Daxx overexpressing myelocytes downregulate the proapoptotic Bcl-2 family member Bax, while expression of antiapoptotic Bcl-2 is not influenced. Furthermore, expression of Daxx diminishes expression levels of the initiator-procaspase-8 and -10, and the executioner procaspase-7, whereas the procaspase-3, -6 and -9 remain unaltered. The altered protein levels of the caspases in Daxx overexpressing myelocytes are accompanied by a decrease of expression levels of the inhibitor of apoptosis proteins (IAPs) cIAP-1, -2 and survivin. Despite the described impact of Daxx expression on major molecules of the apoptotic cascade, expression of Daxx in neoplastic myelocytes does not impact on the rate of proliferation. Upon a proapoptotic stimulus such as serum withdrawal Daxx is unable to maintain its influence on expression levels of p53, Bax, IAPs and the procaspase-8, -10 and -7.

Objective: To explore the possible effect of p27 gene expression on the proliferation and apoptosis of HL-60 and Raji cell lines.

Methods: The infections of HL-60 and Raji cells were performed by the adenovirus-mediated p27 gene transfection approach. The efficiency of Adp27 infection and the expression of p27 mRNA and protein were evaluated by X-gal staining, RT-PCR and flow cytometry. The proliferation and apoptosis of HL-60 and Raji cells were estimated by using trypan blue staining, MTT assay, Annexin V/PI and DNA ladder electrophoresis.

Results: The infection efficiency of HL-60 and Raji cells were 40.3 and 32%, respectively; RT-PCR and flow cytometry showed that there were significant expressions of p27 mRNA and protein of HL-60 and Raji cells infected by Adp27, while HL-60 cells themselves showed only faint p27 mRNA and protein, and Raji cells hardly presented p27 mRNA and protein. The strong proliferation inhibitions, which were in a time-dependent manner for HL-60 and Raji cells infected by Adp27, were indicated by cell growth curve and MTT assay. After 72 h infection of HL-60 and Raji cells by Adp27, the Annexin V+/PI- apoptotic cell rates were 46.9 and 35.7% respectively, which were significantly increased compared with control group (4.7 and 5.6% respectively). The typical DNA ladder bands were detectable in HL-60 and Raji cells after 48 h of Adp27 infection.

Conclusion: The infection of HL-60 and Raji cells by means of adenoviral vector-mediated p27 gene could evidently inhibit cellular proliferation and promote cell apoptosis, which would provide experimental evidence for gene therapy of leukemia/lymphoma using adenovirus-mediated p27 gene approach.

Primary hepatic lymphoma is a rare but well-defined lymphoma entity that often pursues an aggressive clinical course. Most cases have been described in hepatitis C virus (HCV)-related chronic liver disease patients. Although anthracycline-based chemotherapy has been reported to be highly effective, the best therapeutic strategy has not been defined yet. The prognosis is dismal especially in patients treated with chemotherapy alone or when an advanced liver disease is present. Herein, we describe a case of primary hepatic large B-cell non-Hodgkin's lymphoma, in a patient with HCV chronic infection. After a minor response with eight cycles of CHOP chemotherapy, a complete and sustained remission was obtained with alpha-interferon at the daily dose of 3 MU. HCV-RNA clearance pace from the blood almost paralleled the response of the lymphoma and both diseases went in remission within 1 year of therapy. The possible place of alpha-Interferon in the treatment of primary hepatic lymphoma is discussed.