Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We encountered a patient in blast crisis (BC) with chronic myelogenous leukemia (CML) who showed immunophenotypic features similar to those previously described in acute myeloid/natural killer (NK) cell precursor leukemia. The blasts were positive for CD7, CD33, CD34, and CD56. Cytogenetic analysis disclosed a Philadelphia chromosome (Ph) and t(3;7)(q26;q21). Molecular analysis did not detect any EVI1/CDK6 chimeric transcript generated by t(3;7)(q26;q21), but did indicate overexpression of EVI1, which occurs frequently in progression to myeloid BC in CML. Three cases of myeloid/NK cell precursor BC in CML have been reported, but this case is the first to present with Ph and EVI1 abnormality. These observations suggested that a myeloid/NK cell precursor might have been involved in the Ph-positive clone and have been a target for blastic transformation of CML, although EVI1 expression is not specific for transformation to BC from myeloid/NK lineage.
 ...
PMID:Myeloid/natural killer cell blast crisis representing an additional translocation, t(3;7)(q26;q21) in Philadelphia-positive chronic myelogenous leukemia. 1532 64

EVI1 is an oncogene frequently associated with chronic and acute myeloid leukemia. In hematopoietic cells, EVI1 impairs several pathways including proliferation, differentiation, and apoptosis. Interferon-alpha (IFN-alpha) is a powerful cytokine that controls the immune response and limits the expansion of several tissues including bone marrow. These properties contribute to the effectiveness of IFN-alpha in the treatment of many neoplastic disorders especially chronic myeloid leukemia. We report here that in murine hematopoietic progenitors the expression of EVI1 completely abrogates the antiproliferative and apoptotic effects of IFN-alpha. EVI1 does not repress the JAK/STAT signaling pathway or the activation of many IFN-responsive genes. On the contrary, EVI1 prolongs the phosphorylation of STAT1 and the activation of an IFN-dependent reporter gene. However, EVI1 specifically represses the IFN-dependent induction of the tumor suppressor PML and blocks the apoptotic pathways activated by PML. We show that the position of the ISRE, which is located within the first exon of PML, is critical to block PML induction by IFN-alpha. The relocation of the ISRE to a position upstream of the transcription start site is sufficient to re-establish the response to IFN in the presence of EVI1. Our data suggest that stabilized STAT1 phosphorylation and prolonged binding of the STAT1 complex to the first exon could impair PML transcription and inhibit the activation of PML-dependent apoptotic pathways resulting in loss of IFN response. These results point to a novel mechanism utilized by an oncogene to escape normal cell response to growth-controlling cytokines.
 ...
PMID:EVI1 abrogates interferon-alpha response by selectively blocking PML induction. 1551 99

The AML1/EVI1 chimeric gene is created by the t(3;21)(q26;q22) chromosomal translocation seen in patients with leukemic transformation of myelodysplastic syndrome or blastic crisis of chronic myelogenous leukemia. We knocked-in the AML1/EVI1 chimeric gene into mouse Aml1 genomic locus to explore its effect in developmental hematopoiesis in vivo. AML1/EVI1/+ embryo showed defective hematopoiesis in the fetal liver and died around embryonic day 13.5 (E13.5) as a result of hemorrhage in the central nervous system. The peripheral blood had yolk-sac-derived nucleated erythroblasts but lacked erythrocytes of the definitive origin. Although E12.5 fetal liver contained progenitors for macrophage only, E13.5 fetal liver contained multilineage progenitors capable of differentiating into dysplastic myelocyte and megakaryocyte. No erythroid progenitor was detected in E12.5 or E13.5 fetal liver. Hematopoietic progenitors from E13.5 AML1/EVI1/+ fetal liver were highly capable of self-renewal compared with those from wild-type liver. Maintained expression of PU.1 gene and decreased expression of LMO2 and SCL genes may explain the aberrant hematopoiesis in AML1/EVI1/+ fetal liver.
 ...
PMID:Dysplastic definitive hematopoiesis in AML1/EVI1 knock-in embryos. 1591 64

AML1/MDS1/EVI1 (AME) is a chimeric transcription factor produced by the (3;21)(q26;q22) translocation. This chromosomal translocation is associated with de novo and therapy-related acute myeloid leukemia and with the blast crisis of chronic myelogenous leukemia. AME is obtained by in-frame fusion of the AML1 and MDS1/EVI1 (ME) genes. The mechanisms by which AME induces a neoplastic transformation in bone marrow cells are unknown. AME interacts with the corepressors CtBP and HDAC1, and it was shown that AME is a repressor in contrast to the parent transcription factors AML1 and ME, which are transcription activators. Studies with murine bone marrow progenitors indicated that the introduction of a point mutation that destroys the CtBP-binding consensus impairs but does not abolish the disruption of cell differentiation and replication associated with AME expression, suggesting that additional events are required. Several chimeric proteins, such as AML1/ETO, BCR/ABL, and PML/RARa, are characterized by the presence of a self-interaction domain critical for transformation. We report that AME is also able to oligomerize and displays a complex pattern of self-interaction that involves at least three oligomerization regions, one of which is the distal zinc finger domain. Although the deletion of this short domain does not preclude the self-interaction of AME, it significantly reduces the differentiation defects caused in vitro by AME in primary murine bone marrow progenitors. The addition of a point mutation that inhibits CtBP binding completely abrogates the effects of AME on differentiation, suggesting that AME induces hematopoietic differentiation defects through at least two separate but cooperating pathways.
 ...
PMID:The distal zinc finger domain of AML1/MDS1/EVI1 is an oligomerization domain involved in induction of hematopoietic differentiation defects in primary cells in vitro. 1614 Sep 25

Multiplex reverse transcription-polymerase chain reaction (M-RT-PCR) has been proved to possess great clinical potential for simultaneous screening of 29 chromosomal translocations in acute leukemia. To evaluate the clinical value of M-RT-PCR in hematologic malignancies, bone marrow samples from 90 patients with various hematologic malignancies, including 25 acute myelogenous leukemia (AML), 22 acute lymphoblastic leukemia (ALL), 27 chronic myelogenous leukemia (CML), 4 myeloproliferative diseases (MPD), 3 chronic lymphoblastic leukemia (CLL), 3 non-Hodgkin's lymphoma (NHL), 3 myelodysplastic syndrome (MDS), 2 multiple myeloma (MM) and 1 malignant histiocytosis (MH) were subjected to both M-RT-PCR and chromosome karyotypic analysis. Some of cases were subjected to follow-up examination of M-RT-PCR during the period of clinical complete remission (CR) for detection of minimal residual leukemia. In our hand, 12 of 29 chromosomal translocation transcripts including TEL/PDGFR, DEK/CAN, MLL/AF6, AML1/ETO, MLL/AF9, BCR/ABL, MLL/MLL, PML/RARu, TLS/ERG, E2A/HLF, EVI1 and HOXI1 were detected in 57 cases (63.3 %) of the 90 samples, which were in consistency with the results of karyotypic analysis. Furthermore, M-RT-PCR had also shown good clinical relevance when used as an approach to detect minimal residual leukemia. We concluded that M-RT-PCR could be used as an efficient and fast diagnostic tool not only in the initial diagnosis of hematologic malignancies but also in subsequent monitor of minimal residual leukemia.
 ...
PMID:Multiplex reverse transcription-polymerase chain reaction for simultaneous screening of 29 chromosomal translocation in hematologic malignancies. 1735 82

Recurring chromosomal translocations observed in human leukemia often result in the expression of fusion proteins that are DNA-binding transcription factors. These altered proteins acquire new dimerization properties that result in the assembly of inappropriate multimeric transcription complexes that deregulate hematopoietic programs and induce leukemogenesis. Recently, we reported that the fusion protein AML1/MDS1/EVI1 (AME), a product of a t(3;21)(q26;q22) associated with chronic myelogenous leukemia and acute myelogenous leukemia, displays a complex pattern of self-interaction. Here, we show that the 8th zinc finger motif of MDS1/EVI1 is an oligomerization domain involved not only in interaction of AME with itself but also in interactions with the parental proteins, RUNX1 and MDS1/EVI1, from which AME is generated. Because the 8th zinc finger motif is also present in the oncoprotein EVI1, we have evaluated the effects of the interaction between RUNX1 and EVI1 in vitro and in vivo. We found that in vitro, this interaction alters the ability of RUNX1 to bind to DNA and to regulate a reporter gene, whereas in vivo, the expression of the isolated 8th zinc finger motif of EVI1 is sufficient to block the granulocyte colony-stimulating factor-induced differentiation of 32Dcl3 cells, leading to cell death. As EVI1 is not detected in normal bone marrow cells, these data suggest that its inappropriate expression could contribute to hematopoietic transformation in part by a new mechanism that involves EVI1 association with key hematopoietic regulators, leading to their functional impairment.
 ...
PMID:Repression of RUNX1 activity by EVI1: a new role of EVI1 in leukemogenesis. 1757 32

Erythroleukemic blast crisis of chronic myeloid leukemia (CML) is very rare. We report two cases of erythroleukemic blast crisis of CML resistant to imatinib treatment. Both patients made a rapid progression to blast crisis 6 and 4 months after diagnosis while being treated with imatinib 400 mg/day. Bone marrow aspiration revealed predominant erythroid precursors with 65.4% and 54.8% each. There were significant proportions (more than 20%) of myeloblasts among non-erythroid cells. Immunophenotyping revealed expression of glycophorin A confirming erythroleukemic blast crisis. The karyotyping result of patient 1 was 46,XX,t(9;22)(q34;q11.2)[3]/52,idem,+8,+12,+18,+21,+22,+der(22)t(9;22)[17] and that of patient 2 was 46,XX,inv(3)(q21q26.2),t(9;22)(q34;q11.2)[20]. Patient 1 showed no response to imatinib and BMS-354825 in the following bone marrow study. She died of septic shock as a complication of an infection after 69 days of blast crisis. Patient 2 received allogeneic bone marrow transplantation (BMT) in the cytogenetically no response state, but she also died of graft-versus-host disease 9 weeks after BMT. The poor prognosis and rapid progression of disease in both cases were correspondent to most of the reported cases. During the course of the disease of the two patients, we monitored the BCR-ABL chimeric mRNA with real-time quantitative polymerase chain reaction (RT-PCR), and it was found useful in predicting the imatinib response and progression to blast crisis of CML. Although both of our cases showed the typical bad prognosis and findings of erythroleukemic blast crisis of CML, the karyotypes were different from the expected type of t(3;21)(q26;q22). But the relationship between additional changes of EVI1 on chromosome 3q26 shown in case 2, and progression to the erythroleukemic blast crisis need further investigation.
 ...
PMID:[Erythroleukemic blast crisis of chronic myeloid leukemia.]. 1815 35

It remains unresolved how different BCR-ABL transcripts differentially drive lymphoid and myeloid proliferation in Philadelphia chromosome-positive (Ph(+)) leukemias. We compared BCR-ABL transcript type and level with kinase domain (KD) mutation status, genotype, and phenotype in 1855 Ph(+) leukemias. Compared with e1a2/p190 BCR-ABL cases, de novo e13-e14a2/p210 Ph(+) lymphoid leukemia more frequently showed CML-type background, had higher blast-normalized BCR-ABL transcript levels, and more frequent persistent BCR-ABL transcript in the absence of detectable lymphoblasts. Secondary lymphoid blast transformation of CML was exclusively due to e13/e14a2/p210 BCR-ABL but was associated, at a much higher level than p210 myeloid transformation, with acquisition of new KD mutations and/or Ph genomic amplification. In contrast, myeloid blast transformation was more frequently accompanied by new acquisition of acute myeloid leukemia-type chromosomal aberrations, particularly involving the EVI1 and RUNX1 loci. Therefore, higher kinase activity by mutation, transcriptional up-regulation or gene amplification appears required for lymphoid transformation by p210 BCR-ABL.
 ...
PMID:BCR-ABL fusion transcript types and levels and their interaction with secondary genetic changes in determining the phenotype of Philadelphia chromosome-positive leukemias. 1880 62

RUNX1-EVI1 is a chimeric gene generated by t(3;21)(q26;q22) observed in patients with aggressive transformation of myelodysplastic syndrome or chronic myelogenous leukemia. RUNX1-EVI1 has oncogenic potentials through dominant-negative effect over wild-type RUNX1, inhibition of Jun kinase (JNK) pathway, stimulation of cell growth via AP-1, suppression of TGF-beta-mediated growth inhibition and repression of C/EBPalpha. Runx1-EVI1 heterozygous knock-in mice die in uteri due to central nervous system (CNS) hemorrhage and severe defects in definitive hematopoiesis as Runx1-/- mice do, indicating that RUNX1-EVI1 dominantly suppresses functions of wild-type RUNX1 in vivo. Acute myelogenous leukemia is induced in mice transplanted with bone marrow cells expressing RUNX1-EVI1, and a Runx1-EVI1 knock-in chimera mouse developed acute megakaryoblastic leukemia. These results suggest that RUNX1-EVI1 plays indispensable roles in leukemogenesis of t(3;21)-positive leukemia. Major leukemogenic effect of RUNX1-EVI1 is mainly through histone deacetyltransferase recruitment via C-terminal binding protein. Histone deacetyltransferase could be a target in molecular therapy of RUNX1-EVI1-expressing leukemia.
 ...
PMID:Role of the RUNX1-EVI1 fusion gene in leukemogenesis. 1901 45

We previously reported a recurrent t(3;8)(q26;q24) translocation involving EVI1 in five patients with myelodysplastic syndrome or acute myeloid leukemia. Here we report the same structural abnormality in a case of chronic myeloid leukemia in blast phase. The t(3;8)(q26;q24) occurred several months after the initial diagnosis of chronic myeloid leukemia, while the patient was being treated with a tyrosine kinase inhibitor. We confirmed rearrangement of EVI1 by fluorescence in situ hybridization assay using a dual-color break-apart probe set that spans the EVI1 region. Our findings demonstrate that, similar to other recurrent translocations involving 3q26, such as t(3;3) and t(3;21), the t(3;8)(q26;q24) is implicated not only in myelodysplastic syndrome and acute myeloid leukemia, but also in progression of chronic myeloid leukemia. These findings extend the known disease spectrum associated with this cytogenetic aberration.
 ...
PMID:Chronic myeloid leukemia in blast phase associated with t(3;8)(q26;q24). 1966 75


<< Previous 1 2 3 4 5 Next >>