Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596978 (Leukemia)
 15,069 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A child with T-cell acute lymphoblastic leukemia (ALL) is presented who at relapse acquired two Philadelphia chromosomes (Ph). Molecular studies at relapse revealed a rearrangement of the major breakpoint cluster region (M-bcr) on chromosome 22. No rearrangements of the immunoglobulin heavy chain or T-cell beta receptor gene loci were demonstrated. This case supports the hypothesis that leukemogenesis in Ph-positive malignancies is a multi-step process, the first step of which may not necessarily involve acquisition of the Ph.
Leukemia 1994 May
PMID:Late-developing Philadelphia chromosomes in a case of T-cell acute lymphoblastic leukemia. 818 46

The ETS family proteins have a conserved DNA-binding domain and act as transcription factors. Three domains have been recently defined in human ETS-1 proteins and their role could depend upon the nature of alternative transcripts according to whether they possess or lack DNA binding and/or transcriptional activation domain and also point mutation that could affect these important domains. Expression of ETS-1 gene is very complex and is controlled at several levels: the initiation of transcription, alternative splicing, post-translational modification, and protein stability. As a selection apparently exists for ETS-1 gene activation in hematopoietic cells, we investigated a relation between quantitative and qualitative ETS-1 expression and leukemogenesis. Using Northern blot, polymerase chain reaction (PCR), and single strand conformation polymorphism (SSCP) methods, we analyzed quantitative and qualitative ETS-1 expression in a variety of hematological pathologies and cell lines of different origin. Two ETS-1 transcripts of 6.8 and 2.7 kb, resulting from differential polyadenylation site utilization and exhibiting different stability, were observed. We identified, in a great number of patients, the four alternative ETS-1 products, but the relative extent significance of the four transcripts was very different from one patient to another. A non-conservative mutation observed in one case of T-cell acute lymphoblastic leukemia (T-ALL) and in the ETS-1 transactivation domain raised the question of suppressor activity for some ETS-1 products, as it is now known that activators and repressors can be encoded by the same gene and consistently co-expressed in vivo.
Leukemia 1993 Nov
PMID:Quantitative and qualitative variation of ETS-1 transcripts in hematologic malignancies. 823 Dec 46

One of the factors regulating the population size of a clone of proliferating cells is the induction of a physiological suicide mechanism known as apoptosis. We studied apoptosis in the HL-60 human promyelocytic leukemia cell line which differentiates when exposed to phorbol ester (S-cell), and in the PET-cell mutant of HL-60 which is defective in its response to phorbol ester. Exposing S-cells to 12-O-tetradecanoylphorbol 13-acetate (TPA) (3 nM and above) induced morphological changes characteristic of apoptosis (visualized by light microscopy), and induced fragmentation of chromatin DNA to oligonucleosomal lengths. These changes were obvious in 48 h. In contrast, 1000 nM TPA for five days did not induce apoptosis in the PET-cell. DNA fragmentation was induced in both cell lines by A23187 (0.25 microM) and etoposide (7 microM). Novobiocin (600 and 900 microM) induced DNA fragmentation in S-cells, but higher concentrations inhibited fragmentation. Novobiocin is believed to induce DNA fragmentation by a direct action on DNA. In the case of PET-cells, novobiocin did not induce DNA fragmentation at any concentration, and prior treatment of PET-cells with novobiocin (300-1200 microM for 30 min) inhibited DNA fragmentation induced by A23187. Novobiocin inhibited cell growth equally in S-cell and PET-cells. It is concluded that the promyelocytes have the capacity to undergo apoptosis in response to agents which activate protein kinase C, and that the PET-cell has a mutation which disables both protein-kinase C-induced and novobiocin-induced DNA fragmentation, leaving intact the ability of novobiocin to protect DNA from calcium-entry-initiated fragmentation. The elucidation of the lesion responsible for the PET phenotype is likely to increase our understanding of this important pathway for regulating cellular proliferation and how it bears on leukemogenesis and chemotherapy.
Leukemia 1993 Nov
PMID:Phorbol ester induces apoptosis in HL-60 promyelocytic leukemia cells but not in HL-60 PET mutant. 823 Dec 52

Therapy-related acute myeloid leukemia (t-AML), often presenting as myelodysplasia (t-MDS), has become the most serious long-term complication of cancer therapy and offers a unique opportunity to study chemical leukemogenesis. Seven cohorts of patients treated for six different types of primary tumor have been followed closely for leukemic complications, and 115 consecutive patients with t-MDS or t-AML, including 45 cases from the cohorts, have been investigated cytogenetically at our institutions during the past 16 years. In patients primarily treated with alkylating agents, the risk of t-MDS and t-AML increased by approximately 1% per year from 2 to at least 8 years after start of treatment. In most cases, the disease presented as t-MDS with loss of a whole chromosome 5 or 7, or various parts of their long arms, and the leukemias were of FAB-subtypes M1, M2, or M4. In patients treated with drugs targeting at DNA-topoisomerase II, such as etoposide, doxorubicin, 4-epidoxorubicin, or mitoxantrone combined with drugs reacting directly with DNA, such as cisplatin or alkylating agents, the risk of leukemia increased much more steeply from only one year after start of therapy. These early onset cases often presented as overt leukemia of FAB-subtypes M4 or M5 with balanced translocations to chromosome bands 11q23 and 21q22, whereas later onset cases often shared characteristics with cases observed after therapy with alkylating agents alone. Both alkylation of DNA and poisoning of DNA-topoisomerase II may result in development of t-AML with different clinical and cytogenetic characteristics. There may be a synergistic leukemogenic effect between the two types of drug, and in patients with germ cell tumors treated with etoposide, cisplatin and bleomycin, reassessment suggested the risk of leukemia to increase exponentially with increasing doses of cisplatin and etoposide.
Leukemia 1993 Dec
PMID:Therapy-related myelodysplasia and acute myeloid leukemia. Cytogenetic characteristics of 115 consecutive cases and risk in seven cohorts of patients treated intensively for malignant diseases in the Copenhagen series. 825 96

The t(14;19)(q32;q13) is a recurring translocation found in leukemic cells of some patients with chronic lymphocytic leukemia (CLL). The BCL3 gene was identified on chromosome 19 adjacent to the breakpoint of the translocation, and has been proposed to be a candidate proto-oncogene which may play a role in leukemogenesis. The current study of a Japanese patient with CLL revealed that the (14;19) is reciprocal at the molecular level; the BCL3 gene was juxtaposed to the 5' side of the S alpha 1 switch region of the immunoglobulin heavy chain gene (IGH) on the der(14) chromosome, and the IGH gene 5' to the S alpha 1 region was joined to chromosome 19 sequences on the der(19) reciprocal partner chromosome. The breakpoint on chromosome 19 was 16 kb upstream of the first exon of the BCL3 gene and 7 bp of chromosome 19 sequences were deleted at the point of the junction. The t(14;19) translocations so far molecularly analyzed consistently occurred within one of the two S alpha switch regions; however, sequence analysis of the chromosome 19 regions involved in the translocation failed to demonstrate an obvious sequence similarity with the switch region. The chromosomal breaks on chromosome 19 from two CLL patients having the t(14;19) were within Alu repeated sequences.
Leukemia 1993 Dec
PMID:Molecular characterization of the t(14;19)(q32;q13) translocation in chronic lymphocytic leukemia. 825 6

Resistance and/or susceptibility for Friend leukemia virus (FLV)-induced leukemogenesis was examined in the fully H-2 incompatible C57BL/6 (B6)-->C3H radiation bone marrow chimeras (RBMC). The results indicated that B6-->C3H chimeras never developed FLV-induced leukemias when infected with FLV 4 months after bone marrow transplantation (BMT). Spleen cells from B6-->C3H chimeras that were preimmunized with 100 Gy-irradiated FBL-3 cells (FLV-induced leukemic cell line originated from B6 mice) were shown to generate anti-FBL-3 specific T-cell proliferation as well as cytotoxic T cells. We also found that when bone marrow cells from B6 mice were mixed with those from C3H mice and then grafted into supralethally irradiated C3H mice, resulting chimeras whose peripheral blood contained less than 30% C3H-derived (susceptible) cells were refractory to FLV-induced leukemogenesis. On the other hand, when C3H mice were infected with FLV and then supralethally irradiated 5 days later and grafted with bone marrow from B6 donors, they developed leukemias which were of B6 origin. Athymic nu/nu mice of B6 background were again shown to develop leukemia following infection with FLV. Possible implication of these findings on the role of T cell-mediated immune response in resistance to FLV-induced leukemogenesis and the immunocompetent nature of fully H-2 incompatible RBMC were discussed.
Leukemia 1993 Jul
PMID:Friend leukemia virus-induced leukemogenesis in fully H-2 incompatible C57BL/6-->C3H radiation bone marrow chimeras. 832 Oct 19

The number of reported cases of leukemia developing in growth hormone (GH) users worldwide has reached 31. Twelve Japanese cases are briefly reviewed; five each of AML and ALL, and one each of CML and malignant histiocytosis. The underlying diseases of these patients consisted of 8 idiopathic disease, 3 tumors and one Fanconi's anemia. Leukemia occurred during GH treatment in 9 cases and after cessation of GH in 3. The longest interval from the cessation of GH therapy was 10 years. GH administration from a younger age tended to be linked to myeloid type. Risk factors and possible mechanisms of leukemogenesis by growth hormone are discussed, and proposals for the future have been made by the Foundation for Growth Science in Japan.
 ...
PMID:Leukemia and other malignancies among GH users. 837 97

The Cas-Br-E murine leukemia virus is a non-defective retrovirus that induces non-T-, non-B-cell leukemias in susceptible NIH/Swiss mice. A collection of tumors was examined for genomic DNA structure and RNA expression of known or putative proto-oncogenes and one tumor-suppressor gene, with the aim of identifying genes involved in Cas-Br-E-induced non-T-, non-B-cell leukemogenesis. Fli-1, p53, and Evi-1 were found to be rearranged in 72%, 23%, and 18% of the tumors, respectively, whereas no DNA alteration were detected for c-myc, c-myb, Pim-1, Evi-2, and EpoR genes. Evi-1 rearrangements are rarely associated with p53 or Fli-1 alterations. However, rearrangements of these last two genes are very often associated within the same tumor. Moreover, patterns of coordinated expression of critical cell growth-regulating genes are consistently associated with specific tumor types. These data suggest that Cas-Br-E can induce two types of hematopoietic neoplasias by different mechanisms.
Leukemia 1993 Jul
PMID:Expression and DNA rearrangement of proto-oncogenes in Cas-Br-E-induced non-T-, non-B-cell leukemias. 839 16

The MLL gene, located at chromosome 11, band q23, is frequently disrupted by a variety of chromosomal rearrangements that occur in acute lymphoblastic leukemias and in a subset of de novo and secondary acute myeloid leukemias. In both scenarios, MLL rearrangements are associated with distinct clinical features and a poor prognosis. MLL encodes a large protein (MLL) that shares homology with the Drosophila trithorax protein. 11q23 translocations result in the generation of a series of acute leukemia-specific chimeric proteins that contain the N-terminus of MLL and are thought to be crucial to leukemogenesis. In this article, we review the structural features of the MLL fusion proteins as well as the clinical features and molecular diagnosis of acute leukemias containing MLL arrangements.
Leukemia 1996 Jan
PMID:11q23 rearrangements in acute leukemia. 855 42

PML has been identified through its fusion to the RAR alpha gene in acute promyelocytic leukemia (APL). The PML protein is specifically associated to nuclear bodies (NBs) whose alterations in APL were proposed to contribute to leukemogenesis. The role of this nuclear domain (which also harbors the Sp100 autoantigen and the NDP52 protein) is unknown. Here, we show that the PML protein, like Sp100 and NDP52, is induced by interferons (IFNs alpha, beta and gamma) in a large variety of human cells. Interestingly, the NBs that contain the three IFN-induced proteins appear to be associated to speckles labelled by the IFN-mediator Mx1. These observations link NBs to IFN response pathways, which may contribute to the elucidation of the biological role of these structures. In APL cells, IFNs induced both PML and PML/RAR alpha expression, resulting in an increased sequestration of PML and RXRs in the microspeckles induced by the fusion protein. As PML has growth suppressing properties, it may mediate some of the antiproliferative effects of IFN. In APL, inactivation of PML may result in disruption of growth control.
Leukemia 1995 Dec
PMID:Induction of the PML protein by interferons in normal and APL cells. 860 13


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