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

The recurrent translocation t(1;3)(p36;q21) is associated with myelodysplastic syndrome (MDS)/acute myelogenous leukemia (AML) characterized by trilineage dysplasia, especially dysmegakaryopoiesis and a poor prognosis. Recently, the two genes involved in this translocation have been identified: the MEL1 gene at 1p36.3, and the RPN1 gene at 3q21. The breakpoint in RPN1 is centromeric to the breakpoint cluster region of the inv(3) abnormality. Because the MEL1 transcript is detected only in leukemic cells with t(1;3)(p36;q21), ectopic expression of MEL1 driven by RPN1 at 3q21 is thought to contribute to the pathogenesis of t(1;3)(p36;q21) leukemia. However, the precise breakpoint in the patients has not yet been identified. With fluorescence in situ hybridization analysis by use of BAC/PAC probes, we identified the breakpoint at 1p36.3 in three MDS/AML patients with t(1;3)(p36;q21): within the first intron of the MEL1 gene (one patient) or within a 29-kb region located in the 5' region of MEL1 (two other patients). We detected several sizes of MEL1 transcript in two patients including the first patient, although we have not yet clarified whether MEL1 transcripts were different among the patients and whether a truncated MEL1 transcript was expressed in the first patient. This patient showed an unusual clinical profile, repeating progression to overt leukemia and conversion to MDS three times during the 29-month survival period, which might be related to a different molecular mechanism in this patient.
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PMID:Breakpoints at 1p36.3 in three MDS/AML(M4) patients with t(1;3)(p36;q21) occur in the first intron and in the 5' region of MEL1. 1255 31

Patients with myeloid malignancies and either the 3q21q26 syndrome or t(1;3)(p36;q21) have been reported to share similar clinicopathological features and a common molecular mechanism for leukemogenesis. Overexpression of MDS1/EVI1 (3q26) or MEL1/PRDM16 (1p36), both members of the PR-domain family, has been directly implicated in the malignant transformation of this subset of neoplasias. The breakpoints in both entities are outside the genes, and the 3q21 region, where RPN1 is located, seems to act as an enhancer. MEL1 has been reported to be expressed in leukemia cells with t(1;3) and in the normal uterus and fetal kidney, but neither in bone marrow (BM) nor in other tissues, suggesting that this gene is specific to t(1;3)-positive MDS/AML. We report the molecular characterization of a t(1;3)(p36;q21) in a patient with MDS (RAEB-2). In contrast to previous studies, we demonstrate that MEL1, the PR-containing form, and MEL1S, the PR-lacking form, are widely expressed in normal tissues, including BM. The clinicopathological features and the breakpoint on 1p36 are different from cases previously described, and MEL1 is not overexpressed, suggesting a heterogeneity in myeloid neoplasias with t(1;3).
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PMID:Molecular characterization of a t(1;3)(p36;q21) in a patient with MDS. MEL1 is widely expressed in normal tissues, including bone marrow, and it is not overexpressed in the t(1;3) cells. 1471 37

Myeloid leukemia in this series corresponds to the myeloid neoplasms of the 4th WHO classification of pathology and genetics of tumor of haematopoietic and lymphoid tissue. The myeloid neoplasms are composed of six categories, which are 1) myeloproliferative neoplasms (MPN), a new category of 2) myeloid and lymphoid neoplasms with eosinophilia and abnormalities of PDGFRA, PDGFRB or FGFR1, 3) myelodysplastic syndrome (MDS)/MPN, 4) MDS, 5) acute myeloid leukemia (AML) and related precursor neoplasms, and 6) acute leukemias of ambiguous lineage. In MPNs without chronic myelogenous leukemia, the genetic marker of JAK2 V617F is added to the diagnostic criteria for polycythemia vera, essential thrombocythemia and primary myelofibrosis. MDS has the new subtype of refractory cytopenia with unilineage dysplasia composed of refractory anemia, refractory neutropenia and refractory thrombocytopenia. AML with t(9; 11) (p22;q23); MLLT3-MLL, AML with t(6;9) (p23; q34); DEK-NUP214, AML with inv(3) (q21q26.2) or t(3; 3) (q21 ; q26.2); RPN1-EVI1 and AML (megakaryoblastic) with t(1; 22) (p13; q13); RBM15-MKL1 are added to the subtype of AML with recurrent genetic abnormalities, and AML with gene mutations of NPM1 and CEBPA are also added as provisional entities of it. The myeloid neoplasms of the 4th WHO classification are comprehensive and seem to be dynamic by incorporating the results of leukemia researches.
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PMID:[Classification of myeloid leukemias]. 1986 Jan 79

The t(3;3)(q21;q26.2) is known to be mainly observed in hematologic myeloid malignancies, as a form of 3q21q26 syndrome. Cytogenetic abnormalities of 3q21q26 syndrome result in RPN1-EVI1 fusion transcripts involving ecotropic viral integration site-1 (EVI1) at 3q26.2 and ribophorin I (RPN1) at 3q21, and the fusion transcripts play an important role in leukemogenesis and disease progression. They are usually associated with dysplasia, especially of megakaryocytes. Patients with these cytogenetic abnormalities show extremely poor prognosis even with aggressive anti-leukemic therapy. We report a case of blastic crisis of CML with both t(3;3)(q21;q26.2) and t(9;22)(q34;q11.2) and associated severe multilineage dysplasia. The patient showed a poor response to imatinib, dasatinib and aggressive induction therapy. When both t(3;3)(q21;q26.2) and t(9;22)(q34;q11.2) are observed in cases of leukemia with increased blasts, they are best considered as aggressive phases of CML with t(3;3)(q21;q26.2), rather than AML with t(9;22)(q34;q11.2) by 2008 WHO classification.
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PMID:[A case of t(3;3)(q21;q26.2) associated with severe multilineage dysplasia and multi-drug resistance in blastic crisis of chronic myelogenous leukemia]. 2115 45

Acute myelogeneous leukemia (AML) with inv(3)/t(3;3)(q13q25) is associated with aberrant expression of the stem-cell regulator MECOM (aka EVI1). Two bone marrow samples received in the OHSU Knight Diagnostic Laboratories (KDL) Cytogenetics Laboratory for chromosomes and FISH for a question of progression of myelodysplastic syndrome (MDS) to AML showed complex abnormalities including a deletion of chromosome 3q, one with del(3)(q13q25) and the other with del(3)(q22q25). In light of the prognostic importance of the activation of the MECOM oncogene and the concurrent inactivation of the GATA2 tumor suppressor that occurs with the classic inversion of chromosome 3q, fluorescence in situ hybridization (FISH) was performed using two different probe designs to better define the 3q deletions in the two cases. Using the Abbott Molecular Laboratories dual fusion MECOM/RPN1 probe, interphase and metaphase cells in both patients showed a variant single fusion (orange/green/fusion) signal pattern consistent with fusion and deletion. Using the three-color (red/green/aqua) Cytocell EVI1 probe, interphase cells in both cases showed a split red/green signal with the aqua signal remaining with the green signal. The distance between the split signals was generally less than is usually seen in the commonly described inverted chromosome 3. These findings are therefore consistent with a complex inversion and concurrent deletion/deletions of chromosome 3q. Thus, the deletion 3q seen in G-banded chromosomes from bone marrow from these two patients is most consistent with the activation of MECOM and the inactivation of GATA2.
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PMID:MECOM (EVI1) Rearrangements: A Review and Case Report of Two MDS Patients with Complex 3q Inversion/Deletions. 2845 1