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

The molecular cloning of the t(5;10)(q33;q22) associated with atypical chronic myeloid leukemia (CML) is reported. Fluorescence in situ hybridization (FISH), Southern blot, and reverse transcriptase- polymerase chain reaction analysis demonstrated that the translocation resulted in an H4/platelet-derived growth factor receptor betaR (PDGFbetaR) fusion transcript that incorporated 5' sequences from H4 fused in frame to 3' PDGFbetaR sequences encoding the transmembrane, WW-like, and tyrosine kinase domains. FISH combined with immunophenotype analysis showed that t(5;10)(q33;q22) was present in CD13(+) and CD14(+) cells but was not observed in CD3(+) or CD19(+) cells. H4 has previously been implicated in pathogenesis of papillary thyroid carcinoma as a fusion partner of RET. The H4/RET fusion incorporates 101 amino acids of H4, predicted to encode a leucine zipper dimerization domain, whereas the H4/PDGFbetaR fusion incorporated an additional 267 amino acids of H4. Retroviral transduction of H4/PDGFbetaR, but not a kinase-inactive mutant, conferred factor-independent growth to Ba/F3 cells and caused a T-cell lymphoblastic lymphoma in a murine bone marrow transplantation assay of transformation. Mutational analysis showed that the amino-terminal H4 leucine zipper domain (amino acids 55-93), as well as H4 amino acids 101 to 386, was required for efficient induction of factor-independent growth of Ba/F3 cells. Tryptophan-to-alanine substitutions in the PDGFbetaR WW-like domain at positions 566/593, or tyrosine-to-phenylalanine substitutions at PDGFbetaR positions 579/581 impaired factor-independent growth of Ba/F3 cells. H4/PDGFbetaR is an oncoprotein expressed in t(5;10)(q33;q22) atypical CML and requires dimerization motifs in the H4 moiety, as well as residues implicated in signal transduction by PDGFbetaR, for efficient induction of factor-independent growth of Ba/F3 cells. (Blood. 2001;97:3910-3918)
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PMID:H4(D10S170), a gene frequently rearranged in papillary thyroid carcinoma, is fused to the platelet-derived growth factor receptor beta gene in atypical chronic myeloid leukemia with t(5;10)(q33;q22). 1138 34

A 61-year old woman presented to us with fever, weakness and ecchymotic patches for one year. She had leucocytosis, anemia and thrombocytopenia. Peripheral blood smear showed 62% neutrophils, 32% myelocytes and metamyelocytes, 2% promyelocytes, 1% blasts, 2% monocytes, 1% lymphocytes but no basophils and marked dyspoiesis. Bone marrow picture was essentially the same. A diagnosis of atypical chronic myeloid leukemia was suggested. The correct diagnosis of chronic myeloid leukemia-accelerated phase was, however, made on cytogenetic analysis which showed Philadelphia chromosome (Ph) and isochromosome 17q [i(17q)]. This case describes a rare and diagnostically difficult presentation of CML arising out of a combination of prominent dyspoiesis and near absence of peripheral blood basophils.
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PMID:Chronic myeloid leukemia presenting with absence of basophils and marked dyspoiesis. 1471 11

We report a case of BCR-ABL-negative atypical chronic myeloid leukemia (CML) with translocation t(4;22) (q12;q11.2) juxtaposing the breakpoint cluster region (BCR) and platelet-derived growth factor receptor-alpha (PDGFRA) genes. The patient was a 57-year-old man with a history of stage IV diffuse large B-cell lymphoma, status post-6 cycles of combination chemotherapy in 1999, who presented in August 2002 with enlarged lymph nodes, anemia, and marked leukocytosis (50 x 10(9) g/dL) consistent with a myeloproliferative disorder (MPD). A bone marrow biopsy showed granulocytic hyperplasia, neutrophilia, and mild eosinophilia. Initial cytogenetic evaluation by interphase FISH for BCR-ABL, to rule out a translocation 9;22, showed a variant signal pattern consistent with rearrangement of BCR at 22q11.2, but not ABL at 9q34. Analysis of the patient's cDNA by polymerase chain reaction (PCR) for BCR-ABL was negative. Cytogenetic analysis showed an abnormal karyotype with rearrangement of chromosomes 4 and 22. PCR amplification and subsequent sequence analysis demonstrated an in-frame 5'-BCR/3'-PDGFRA fusion in the patient's cDNA. PDGFRA encodes a receptor tyrosine kinase and shares structural and organizational homology with the KIT and CSf1R receptor genes. However, although the incidence of MPD involving translocations of PDGFRB has been well established, to our knowledge there are only two previous reports describing a BCR-PDGFRA fusion gene, in 3 patients diagnosed with atypical CML. Here, we report the molecular and cytogenetic characterization of a patient with BCR-PDGFRA-positive MPD who had a complete hematologic response after treatment with imatinib mesylate.
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PMID:Molecular and cytogenetic characterization of a novel translocation t(4;22) involving the breakpoint cluster region and platelet-derived growth factor receptor-alpha genes in a patient with atypical chronic myeloid leukemia. 1503 67

The myeloproliferative disorders (MPDs) are chronic malignant conditions originating from the clonal expansion of a multipotential hematopoietic stem cell. These diseases include polycythemia vera (PV), essential thrombocythenia, atypical chronic myeloid leukemia, idiopathic hypereosinophilic syndrome (HES), agnogenic myeloid metaplasia with myelofibrosis, and others. Receptor tyrosine kinases-the platelet-derived growth factor receptors (PDGFRs) and c-Kit-and their respective ligands have been implicated in the pathogenesis of MPDs. For example, a constitutively activated PDGFR fusion tyrosine kinase (FIP1L1-PDGFRA) was identified in some patients with HES, a disease characterized by sustained overproduction of eosinophils that has been classified by the World Health Organization as a chronic subtype of the MPDs. Imatinib is a selective inhibitor of PDGFRs, c-Kit, Abl and Arg protein-tyrosine kinases, as well as Bcr-Abl, the oncogenic tyrosine kinase that causes chronic myeloid leukemia. The efficacy of imatinib in treating HES, systemic mast cell disease, chronic myelomonocytic leukemia associated with PDGFRbeta fusion genes, and (to a lesser extent) PV and idiopathic myelofibrosis was reviewed from institutional experience and a review of the literature. In 3 studies that involved 11 patients with PV, 10 patients had reductions in phlebotomy with imatinib. Eight studies of 42 patients with HES indicated that 70% achieved complete hematologic remissions with imatinib. Four studies of 6 patients with MPD indicated responses with imatinib in 5 patients. Insight into the molecular pathogenesis of MPDs will improve the definitions of different disease categories and suggests that signal transduction inhibition is likely to be an increasingly important treatment option in the future.
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PMID:Beyond chronic myelogenous leukemia: potential role for imatinib in Philadelphia-negative myeloproliferative disorders. 1513 47

We describe the fusion of TP53BP1 to PDGFRB in a patient with a chronic myeloid leukemia-like disorder associated with eosinophilia and a t(5;15)(q33;q22). TP53BP1 encodes 53BP1, a p53-binding protein that plays a role in cellular responses to DNA damage. The 53BP1-PDGFRbeta fusion protein is predicted to retain the kinetochore-binding domain of 53BP1 fused to the transmembrane and intracellular tyrosine kinase domain of PDGFRbeta. The presence of the fusion was confirmed by two-color fluorescence in situ hybridization, reverse transcription-PCR, and by characterizing the genomic breakpoints. The reciprocal fusion, which would contain the p53-binding 53BP1 BRCA1 COOH-terminal domains, was not detectable by fluorescence in situ hybridization or nested PCR. Imatinib, a known inhibitor of PDGFRbeta, blocked the growth of patient colony-forming unit, granulocyte-macrophage in vitro and produced a clinically significant response before relapse and subsequent death with imatinib-resistant disease. We conclude that TP53BP1-PDGFRB is a novel imatinib target in atypical chronic myeloid leukemia.
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PMID:p53-Binding protein 1 is fused to the platelet-derived growth factor receptor beta in a patient with a t(5;15)(q33;q22) and an imatinib-responsive eosinophilic myeloproliferative disorder. 1549 36

Atypical chronic myeloid leukemia (aCML) occurs rarely and is associated with a poor prognosis when treated with conventional chemotherapy. We evaluated the outcome of aCML after allogeneic hematopoietic stem cell transplantation (HSCT). Nine patients were transplanted from HLA-identical siblings (n = 4), HLA-compatible unrelated donors (n = 4) or twin brother (n = 1). Median follow-up was 55 months after transplant (range, 9.1-118.1 months). One patient who was transplanted in advanced disease with bone marrow from his twin brother relapsed 19 months post transplant. This patient was successfully retransplanted from the original donor. All patients remained in complete remission. Analysis of the leukocyte chimerism of peripheral white blood cells and bone marrow buffy coat cells by VNTR-polymerase chain reaction (PCR) and single-nucleotide polymorphism real-time PCR revealed complete chimerism in all patients who had received an allogeneic transplant. One patient suffering from cerebral toxoplasmosis died 9 months post transplant. All other patients were alive at the time of analysis. Our findings suggest that the outcome of allogeneic or syngeneic transplantation in patients with aCML may not be worse than the outcome of transplantation for BCR-ABL-positive CML.
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PMID:Outcome of hematopoietic stem cell transplantation in patients with atypical chronic myeloid leukemia. 1551 46

The case of a patient presenting with a myeloproliferative disorder (MPD) characterized by a t(8;22) (p12;q11) translocation was investigated. The rearrangement resulted in the production of BCR-FGFR1 and FGFR1-BCR chimeric transcripts after in-frame fusions of BCR exon 4 with FGFR1 exon 9 and FGFR1 exon 8 with BCR exon 5, respectively. The four previously reported patients with such translocation presented with an atypical chronic myeloid leukemia (CML) without Philadelphia chromosome. In addition to a myeloproliferation, the patient had a B cell proliferation. The phenotypic characterization of the lymphoid cells in the bone marrow showed a continuum of maturation from blast B cells to polyclonal lymphocytes. In the blood, B cells showed a complete polyclonal maturation. The BCR-FGFR1 gene fusion was detected by dual-color fluorescence in situ hybridization in both CD19- and CD19+ populations. In contrast to the other FGFR1-MPDs that show myeloid and T cell proliferation, we propose that this t(8;22) MPD is a myeloid and B cell disease, and potentially a novel type of hematological disease. Although the FGFR1-MPD is rare, its study provides interesting clues to the understanding of hematopoietic stem cell biology and oncogene activation.
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PMID:Dual lympho-myeloproliferative disorder in a patient with t(8;22) with BCR-FGFR1 gene fusion. 1587 Aug 60

The WHO classification published in 2001 defined a new category of hematological disease, myelodysplastic/myeloproliferative diseases (MDS/MPD), that have both myelodysplasia and myeloproliferation at the time of initial presentation. This category consists of four subclasses, chronic myelomonocytic leukemia (CMML), atypical CML(aCML), juvenile chronic myelogenous leukemia and MDS/MPD-unclassifiable (MDS/MPD-u). In order to clarify the clinical features of these diseases, we analyzed clinical data of tentatively diagnosed MDS/MPD cases in the past ten years accumulated from affiliated hospitals. By reviewing the data of each case according to the criteria, we diagnosed 31 cases of MDS/MPD, including 22 cases of CMML, 5 cases of aCML and 4 cases of MDS/MPD-u. Male predominance and high age were common among these three subclasses. The prognosis of CMML was poor compared to other subclasses because of the high incidence of blast crisis. It is noteworthy that blast crisis in CMML exclusively occurred within one year after diagnosis. Young age, a high percentage of blasts in the peripheral blood, splenomegaly, lymphadenopathy and clonal cytogenetic abnormality were associated with blast crisis. It is suggested that there are two subgroups in CMML which differ in disease progression. Thus, these indicators may be useful in deciding the therapeutic strategy including hematopoietic cell transplantation for the high risk subgroup. There were four MDS/MPD cases with a history of preceding hematological diseases, such as aplastic anemia, MDS or malignant lymphoma. Among these, three cases with a long-term history of treatment with metenolone acetate developed CMML. It is suggested that the long-term effect of androgen plays a role in the pathophysiology of CMML.
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PMID:[Clinical features of a new category, myelodysplastic/myeloproliferative diseases, defined by WHO classification]. 1663 72

The World Health Organization criteria for diagnosing chronic myelomonocytic leukemia (CMML) are largely based on findings observed in the peripheral blood and bone marrow aspirate. A specific diagnostic role for the bone marrow biopsy has not been adequately explored. We examined whether bone marrow biopsy supplemented by immunohistochemistry may be helpful in distinguishing CMML from cases of chronic myelogenous leukemia and atypical chronic myeloid leukemia (aCML). We immunostained 25 cases of CMML with paraffin reactive antibodies which included CD68 (KP1), CD68R (PG-M1), and CD163, and compared the results with those observed in six cases of chronic myelogenous leukemia and in three cases of atypical CML. In addition, we examined whether CD34 immunohistochemistry could be useful in separating cases of CMML with less than 10% blasts (type-1) from cases of CMML with blasts accounting for 10-19% (type-2), and cases of CMML in acute transformation to acute myeloid leukemia (blasts > or = 20%). The presence of nodules of plasmacytoid monocytes was investigated by CD123 staining. CD42b was used to highlight abnormal megakaryocytes. Our results demonstrate significant differences between the groups. CD34 analysis allowed separating CMML type-1 from type-2 and the former from CMML in acute transformation. CD123-positive plasmacytoid monocyte nodules were found only in CMML and not in the other two disease groups. Overlap between CMML and the other two groups were observed with CD68 immunostaining. CD68R was more restricted to bone marrow macrophages and monocytes than CD68, but the differences between CMML and chronic myelogenous leukemia or atypical CML were still not significant. Although CD42b immunostaining facilitated the detection of dwarf megakaryocytes often present in CMML, the distinction between those and the small forms seen in chronic myelogenous leukemia was still problematic.
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PMID:Chronic myelomonocytic leukemia: The role of bone marrow biopsy immunohistology. 1704 67

In the WHO classification atypical chronic myeloid leukemia (CML) has been considered as a new distinct clinical entity included in the category of mixed myeloproliferative/myelodysplastic disorders. Little is known about this uncommon disease, whose incidence is about of one-two cases every 100 cases of Ph-positive CML. We analyzed our series of 55 patients diagnosed as having aCML, with the aim of identifying clinical factors of possible prognostic value on survival and acute transformation.
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PMID:Identification of risk factors in atypical chronic myeloid leukemia. 1704 19


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