Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the present study fresh leukemic cells obtained from 23 patients with acute myeloid leukemia (AML; FAB subtypes: three M1, five M2, two M3, five M4, eight M5) were investigated for the membrane expression of the CD4 molecule by cytofluorimetric analysis with an anti-CD4 monoclonal antibody (mAb). In 15 cases the presence of the CD4 mRNA was also investigated using Northern blot analysis. Membrane expression of the CD4 molecule was demonstrated in 19 out of 23 cases, and it was found to be weaker than in CD4+ lymphocytes and monocytes obtained from normal controls. Full-length CD4 mRNA was detected in 12 out of 15 (80%) cases, and AML cells positive for CD4 mRNA expression also expressed the CD4 antigen. Since the CD4 molecule expressed by T cells is associated with p56lck, a member of the src family of intracellular tyrosine kinases, we investigated whether the CD4 molecule expressed by myeloid blasts is also associated with a tyrosine kinase activity. In vitro kinase assays performed on anti-CD4 immunoprecipitates from lysates of myeloid leukemia cells from four CD4+ cases were negative for the presence of a tyrosine kinase activity. This finding was not due to the lack of expression of members of the src family since we were able to detect at least p60src and p59fyn in myeloid leukemia cells. According to our results, the CD4 molecule seems to belong to the phenotypic repertoire of most AML, irrespective of their FAB subtypes. However, in myeloid blasts this molecule is not associated with a tyrosine kinase activity as it occurs in T lymphocytes.
Leukemia 1992 Dec
PMID:The CD4 molecule belongs to the phenotypic repertoire of most cases of acute myeloid leukemia. 145 71

Murine radiation-induced acute myeloid leukemia (RI-AML) may be considered as the experimental counterpart of human secondary leukemia. Three new myelomonocytic cell lines derived from RI-AML and carrying a partially deleted chromosome 2 are described. The RI-AML cells responded with increased proliferation after being incubated with the hemopoietic growth factors rG-CSF, rGM-CSF and IL-3. Increased proliferation of the same extent without any effect in differentiation, was also demonstrated in the RI-AML cells after incubation with IL-6 and with mouse lung conditioned medium (CM) and Krebs ascites tumor cells CM which induce differentiation in normal and most leukemic myeloid cells. Down-regulation of the c-myc gene and induction of (2'-5') oligo-adenylate synthetase (reflecting autocrine interferon secretion), two essential mechanisms operating during arrest of growth and concomitant differentiation, were demonstrated to be absent in RI-AML cells. In contrast, the M1 cells responded to the above differentiating factors with growth arrest and differentiation and with appropriate c-myc down-regulation and synthetase induction. The genetic basis for the distinct RI-AML cells' behavior may be connected with the loss or structural and/or functional abnormalities of DNA sequences located in the deleted part of chromosome 2 or in the respective allele. The presently described new RI-AML cell lines may be used for studies concerning myeloid leukemogenesis in general and secondary leukemia in particular.
Leukemia 1992 Dec
PMID:Absence of negative growth regulation in three new murine radiation-induced myeloid leukemia cell lines with deletion of chromosome 2. 145 74

The aim of this study was to investigate to which extent acute leukemias could be monitored for residual disease by using atypical antigen combinations as leukemia-related markers. Atypical antigenic features were determined by double color flow cytometry and included coexpression of lymphoid and myeloid related antigens, unphysiological coexpression of immature and mature antigens, and lack of an antigen that is normally expressed during maturation. Atypical immunophenotypes were detected in 35 of 68 patients with AML (51.5%) and 15 of 24 patients with ALL (62.5%). When 12 patients with leukemia-associated markers were again analyzed at relapse, the relevant antigen combinations were retained in 11 of them. The sensitivity of this two color flow cytometric assay as determined in dilution experiments was 1 in 10(3) to 10(4) cells. Follow-up studies of bone marrow samples revealed that, after induction chemotherapy cells with leukemia-associated markers were detectable in several patients at a frequency of 0.5 to 4%, but only patients in whom the cells with atypical antigens never disappeared suffered from relapse. In contrast, patients who became negative for the atypical cells remained in complete remission (median remission duration after the first negative bone marrow assessment by flow cytometry 52 weeks, range 20-102). We conclude that atypical antigen combinations, which are present in a meaningful number of acute leukemias, are a valuable means of monitoring acute leukemia patients during follow-up. This flow cytometric approach can complement other strategies to get a more accurate definition of remission in acute leukemia.
 ...
PMID:Flow cytometric determination of atypical antigen expression in acute leukemia for the study of minimal residual disease. 145 6

Trisomy 13 occurring as a sole cytogenetic abnormality has recently been demonstrated to have adverse prognostic significance in acute leukemia. Trisomy 13 is seen primarily in an older male population, and has been reported in treatment-associated acute leukemia and acute leukemia evolved from myelodysplastic syndromes, as well as in de novo leukemia. The 36 cases of acute leukemia with trisomy 13 reported to date include 26 AML, 6 AUL, 2 ALL and 2 mixed lineage patients. Immunophenotyping studies have demonstrated an undifferentiated phenotype or biphenotypic markers in most cases. Trisomy 13 is associated with a low complete remission rate and with brief remission duration. The role of the additional copy of chromosome 13 in the pathogenesis of these cases of acute leukemia and the gene(s) of importance on chromosome 13 are yet to be determined.
 ...
PMID:Trisomy 13 in acute leukemia. 147 19

A 78-year-old male developed acute myeloid leukemia (AML, M2) with an isochromosome 11q (i(11q)) in hypo-triploid populations. He died 2 months later from the leukemia without having responded to chemotherapy. We reviewed 12 cases in the literature with i(11q) in hematopoietic neoplasms and found that the i(11q) is associated with complex chromosome abnormalities and with elderly patients. Ten out of the 13 patients had an AML phenotype, and they had poor response to chemotherapy and a short survival. The i(11q) may be a non-random chromosome aberration in hematopoietic neoplasms.
 ...
PMID:Hypo-triploid acute myeloid leukemia with isochromosome 11q. 147 31

The prognosis and long-term results of a group of 57 acute megakaryoblastic leukaemia (M7-AML) patients was analysed from a multicentre perspective. Ages ranged from 4 to 83 years, median 49 years; 30 were males and 27 were females. The median follow-up time was 7 months, range 1-24 months. Early exits occurred in 12 cases, their median age being 71 years. Forty-five patients were treated with combined aggressive chemotherapy (CT) (n = 26) or low-dose cytarabine (LD-AraC) (n = 19). The following results were obtained with combined CT or AraC, respectively. Complete remission (CR) rates were 73% and 84%, 12-month survival (SV) were 37% and 26%, 24-month SV were 12% and 11%, median SV 10 and 4 months, and relapse rates (RR) were 68% and 94%. These differences were not statistically significant. Irrespective of the treatment modality, the results were better for children (n = 10) than for adults (n = 35): RR rates were 90% and 74%, median SV: 7 and 5 months, 12-month SV: 40% and 22%, 24-month SV; 30% and 9%, and RR: 78% and 81%, respectively; these differences also were not statistically significant. In addition, a literature review of 42 patients from 18 previous reports is presented, including seven cases treated with allogeneic bone marrow transplantation (BMT). The best results were obtained with BMT: 12 and 24 month SV was 86% and the RR was 0%. On the above-mentioned basis, we feel that children and young adults with M7-AML should be offered BMT. In patients over 60 years old or not eligible for aggressive chemotherapy or BMT, an interesting possibility would be the use of LD-AraC which allows a high CR rate, followed by a classical consolidation regimen in order to prevent early relapses.
 ...
PMID:Long-term treatment results for acute megakaryoblastic leukaemia patients: a multicentre study. 148 53

Leukaemia is rare in infancy with an equal predominance of lymphoblastic and myeloblastic cases. Acute lymphoblastic leukaemia in infants under one year is characterised by a high leucocyte count, organomegaly, early B-cell phenotype, sometimes with evidence of monocytoid differentiation and cytogenetic abnormalities. This is reflected in its poor prognosis. The toddler (aged 1-2) tends to develop typical childhood ALL which is responsive to treatment, but remains vulnerable to late effects of therapy, particularly radiation. The distribution of subtypes of AML differs in the younger and older child and results of treatment have improved in all age groups. A uniform strategy appears desirable for all cases of childhood AML. It seems probable that different genetic and environmental factors may be involved in the genesis of infant ALL, childhood ALL and AML in children. The management of leukaemia in children under two poses a considerable challenge.
 ...
PMID:Leukaemia in the young child. 150 27

Clinical, morphological, immunological, cytogenetical and prognostic features of 84 children under 2 years of age with AML in studies AML-BFM-78, -83 and -87 were retrospectively analysed. There was a high incidence of acute monoblastic leukaemia (FAB M5) (41 patients--49%) and acute megakaryoblastic leukaemia (FAB M7) (study AML-BFM-87: five patients--13%) in this age group. Acute monoblastic leukaemia was associated with hepatosplenomegaly, extramedullary organ manifestations and chromosomal abnormalities involving 11q23. The probability of an 11-year event-free survival of all patients under 2 years of the three studies combined was 39% (SD 6%). While the event-free survival rates of patients aged 2 years and older could be improved in studies AML-BFM-83 and -87 compared with study AML-BFM-78, overall prognosis in children under 2 years in the three consecutive studies remained unchanged. The event-free survival rate of children with acute monoblastic leukaemia in both age groups was comparable (7 yr-EFS (AML-BFM-83 and -87): much less than 2 years--43% (SD 9%), =/much greater than 2 years--33% (SD 9%); P much greater than 0.5). This also applied to other risk groups. In conclusion, taking the high incidence of acute monoblastic and megakaryoblastic leukaemia in children under 2 years into account, no significant differences between children under 2 years or older children concerning response to therapy and overall prognosis could be evaluated.
 ...
PMID:Acute myelogenous leukaemia in children under 2 years--experiences of the West German AML studies BFM-78, -83 and -87. AML-BFM Study Group. 150 29

In conclusion, hematopoietic growth factors have been shown to enhance the recovery and function of circulating WBCs after standard-dose cancer therapy or high-dose cancer therapy with ABMT, and preliminary data strongly suggests that these agents may have the ability to restore leukocyte numbers and competence in AIDS, myelodysplastic syndromes, and other marrow failure states. Phase I and II trials of GM-CSF in patients with AIDS, cancer, marrow failure states, and following bone marrow transplantation have been published, and limited phase III randomized trial experiences have been reported as well. Overall, GM-CSF represents a fascinating molecule with which to modulate human hematopoiesis in vivo. The multilineage stimulatory effects of GM-CSF that are evident in vitro have not been striking or consistent in clinical trials. However, the effects of GM-CSF on the production and function of mature neutrophils, monocytes, and eosinophils have been noted in the vast majority of clinical scenarios in which this cytokine has been tested. The clinical benefits of GM-CSF have, to date, only been proven in large-scale randomized studies of recovery from ABMT for lymphoid neoplasms. However, further data regarding the use of GM-CSF in other clinical settings have been generated, and the final results are eagerly anticipated by the oncology community. The beneficial effects of GM-CSF following ABMT consisted not only of a shorter period of absolute neutropenia, but also fewer significant infections, a diminished requirement for intravenous antibiotic administration, and a shorter overall duration of inpatient hospitalization. The use of GM-CSF in clonal disorders of hematopoiesis, such as myelodysplasia or myeloid leukemias, requires caution before such applications can be routinely recommended, and the demonstration of safety in this setting from large randomized trials will be needed. Preliminary data from small randomized trials suggests that the incidence of evolution to leukemia in patients with myelodysplasia and the number of patients with regrowth of leukemia after induction treatment in relapsed patients with AML may not be significantly different than in patients who do not receive GM-CSF. Various neutropenic conditions (eg, idiopathic or congenital) may respond clinically to hematopoietic growth factors such as GM-CSF. Patients treated for 3 to 15 months continue to respond with significantly increased granulocytes and resolution of prior infection. The subcutaneous route of administration is convenient and patients seem to accept it readily. It is difficult to determine the extent to which adjunctive therapy with GM-CSF will be cost effective.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Granulocyte-macrophage colony-stimulating factor (GM-CSF): preclinical and clinical investigations. 150 75

The chromosomal classification system of childhood acute leukemia according to ploidy or structural chromosomal changes of leukemia cells is clinically useful for the prediction of the treatment outcome. While patients with hyperdiploid (greater than 50 chromosomes) ALL enjoy the best prognosis, those with hypodiploid or pseudodiploid ALL are expected to have unfavorable clinical outcome. Among various translocations or deletions in ALL, t(4;11), t(9;22) and t(8;14) predict the worst clinical outcome. AML patients with t(8;21) or inv (16) have better 50% survival than those with other chromosome changes or normal diploidy. Chromosome analysis of leukemia cells should be included in the diagnostic workup of childhood acute leukemia.
 ...
PMID:[Chromosome abnormalities and prognosis in childhood acute leukemia]. 151 47


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>