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Acute Myeloblastic Leukaemia (acute + myeloblastic_leukaemia)
Selected AbstractsSignificant cytotoxic activity in vitro of the EGFR tyrosine kinase inhibitor gefitinib in acute myeloblastic leukaemiaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2008Elin Lindhagen Abstract Objectives:, Gefitinib inhibits epidermal growth factor receptor (EGFR) signalling, but may also act by non-EGFR dependent mechanisms. We have investigated the activity of gefitinib in haematological tumour cells, in particular acute myeloblastic leukaemia (AML). Methods:, Cytotoxic activity of gefitinib, alone or in combination with standard anti-leukaemic drugs, was assessed by the short-term fluorometric microculture cytotoxicity assay in tumour cells from 117 patients representing five haematological and five non-haematological malignancies. In AML, the EGFR status was analysed by immunochemistry. Gefitinib-induced apoptosis was investigated in a subset of AML samples, as well as in the leukaemia cell line MV-4-11, using a multiparametric high content screening assay. To confirm activation of caspase-3 in cells treated with gefitinib, a blocking test was carried out in which MV4-11 cells were pretreated with the specific caspase inhibitor DEVD-FMK. Results:, Gefitinib showed highest cytotoxic activity in AML (n = 19) with many samples being sensitive at concentrations achievable in clinical practice (<10 ,M), and no difference between previously untreated and relapsed patients. No correlation between the activity of gefitinib and standard antileukaemic drugs (cytarabine, doxorubicin, etoposide) was observed. Combining gefitinib with these drugs resulted in mainly additive or synergistic (etoposide) effects, with no evidence of sequence dependency. The AML cells did not express the EGFR. Gefitinib induced apoptosis, which was at least partly mediated by activation of the caspase-3 pathway. Conclusion:,In vitro, gefitinib has significant cytotoxic activity in AML by inducing apoptosis through non-EGFR dependent pathways. [source] Otological manifestations of acute leukaemia: report of two cases and review of literatureINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2001E. Andrès Otological manifestations exceptionally reveal acute leukaemia, whereas leukaemic infiltration of any tissue is frequent at postmortem examination. We present two cases of acute myeloblastic leukaemia revealed by a loss of hearing due to a middle-ear leukaemic infiltration. The characteristics of such a clinical and radiological finding are emphasized. It is suggested that middle and inner ear can be a ,sanctuary' localization, which might sometimes require radiation therapy to achieve durable and complete remission. [source] Successful treatment of disseminated Geotrichum capitatum infection with a combination of caspofungin and voriconazole in an immunocompromised patientMYCOSES, Issue 3 2008A. Etienne Summary Disseminated Geotrichum capitatum infection is uncommon, and has been reported exclusively in immunocompromised patients. The prognosis is poor with a mortality rate of approximately 50,75%. We report a case of disseminated G. capitatum infection in a severely neutropenic patient who was receiving chemotherapy for acute myeloblastic leukaemia. G. capitatum was isolated from blood cultures, skin lesions, bronchoalveolar lavage fluid, throat swabs and stools. The infection was successfully cured with a combination of voriconazole and caspofungin. [source] Bundles of Auer rods in blast cells and mature neutrophils in a non-promyelocytic acute myeloblastic leukaemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2008Estelle Guérin No abstract is available for this article. [source] Contrasting in vitro effects for the combination of fludarabine, cytosine arabinoside (Ara-C) and granulocyte colony-stimulating factor (FLAG) compared with daunorubicin and Ara-C in P-glycoprotein-positive and P-glycoprotein-negative acute myeloblastic leukaemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 2 2000Y. Higashi It has been suggested that the FLAG remission induction regimen comprising fludarabine (F-ara), cytosine arabinoside (Ara-C) and granulocyte colony-stimulating factor (G-CSF) may be capable of overcoming P-glycoprotein (P-gp)-related multidrug resistance (MDR) in patients with acute myeloblastic leukaemia (AML). We have investigated the in vitro response of P-gp-positive and -negative AML clones to FLAG and compared this with their response to treatment with Ara-C and daunorubicin (DNR). Twenty-four cryopreserved samples from patients with AML were studied using a flow cytometric technique for the enumeration of viable (7-amino actinomycin D negative) cells. Samples consisted of 12 P-gp-positive and 12 P-gp-negative cases, as measured by the MRK16 antibody. The results were analysed by calculating the comparative drug resistance (CDR), i.e. the percentage cell death caused by Ara-C + DNR subtracted from the percentage cell death, caused by FLAG after 48 h incubation in suspension culture. P-gp-positive clones were shown to have a significantly higher CDR than P-gp-negative clones (P = 0·001). Furthermore, a significant positive correlation (r2 = 0·40, P < 0·01) was found between P-gp protein expression and CDR. However, P-gp function, measured using cyclosporin modulation of rhodamine 123 (R123) uptake, was not associated with the CDR, demonstrating that there are other properties of P-gp, besides its role in drug efflux, that modulate the responsiveness of AML blasts to chemotherapy. These results are consistent with a potential benefit for FLAG in P-gp-positive AML, but not P-gp-negative AML, compared with standard anthracycline and Ara-C therapy. [source] Detection of different Ikaros isoforms in human leukaemias using real-time quantitative polymerase chain reactionBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2000S. Olivero The Ikaros gene is an essential regulator in development and haematopoiesis. Dysregulated Ikaros gene expression participates in leukaemic processes, as evidenced in animal models, and by analyses of blast-cell populations from leukaemic patients. We used real-time quantitative polymerase chain reaction (PCR) to evaluate the relative abundance of several Ikaros transcript isoforms in a variety of leukaemic-cell samples. Total RNA was isolated from bone-marrow or blood-cell samples collected at diagnosis in children or adult patients, 18 of whom had acute myeloblastic leukaemia (AML), 61 of whom had acute lymphoblastic leukaemia (ALL) and 11 of whom had chronic myeloid leukaemia (CML). The ratio (Ik1 + Ik2)/(Ik1 + Ik2 + Ik4 + Ik7 + Ik8) ranged from 13·5% to 85% and was lower (P < 0·05) in samples from patients with m-bcr-abl ALL. An alternative splicing resulting in the deletion of 30 nucleotides at the end of exon 6 was observed in leukaemic samples, and in normal thymus and bone marrow. Our results are consistent with previous reports and suggest that the pattern of expression of the different human Ikaros isoforms are not homogeneous among different subsets of leukaemias. [source] The incidence and survival of acute de novo leukaemias in Estonia and in a well-defined region of western Sweden during 1982,1996: a survey of patients aged ,65 yearsJOURNAL OF INTERNAL MEDICINE, Issue 1 2004E. Luik Abstract. Objectives., To compare the incidence and survival of acute de novo leukaemias with particular reference to political/socio-economic and environmental factors in two neighbouring countries over the three 5-year periods (1982,1996). Patients., The present report covers only patients diagnosed when aged ,65 years. Setting., A well-defined area of Sweden, the so-called Western Swedish Health Care Region and Estonia. Population-wise, the western Swedish Region and Estonia are very similar; area-wise they are also well comparable. Results., The number of acute de novo leukaemias was quite dissimilar in the two countries (Estonia, n = 137, Sweden, n = 354). The age standardized incidence rates regarding the total number of acute de novo leukaemias was 5.31 per 100 000 inhabitants/year for Estonia and 7.99 for Sweden, this difference being statistically significant. However, the difference was merely attributable to incidence rates as regards acute myeloblastic leukaemias (AML); on the contrary, differences as regards acute lymphoblastic leukaemias (ALL) and non-classifiable, undifferentiated or biphenotypic acute leukaemias (uAL) were negligible. The relative survival for the total material of patients was significantly higher for Swedish when compared with Estonian patients (P < 0.001). Thus, the relative survival for the total material of patients aged ,65 years in Estonia at 1 year was 8.5% and at 3 years 3.5% respectively. The corresponding figures for the Swedish patients were considerably higher, 22.7 and 7.7% respectively. This difference, however, applied only for patients with AML (P < 0.001), whereas the results for patients with ALL and uAL were equally dismal. Conclusion., The results clearly reflect how political and socio-economic factors may influence the survival of acute leukemia patients in two neighbouring countries. 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