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)

Among 84 consecutive patients with chronic phase Ph-positive chronic myeloid leukemia (CML) who were investigated for the hybrid BCR/ABL mRNA, in six cases (7%) the disease mimicked essential thrombocythemia (ET) at presentation, because of marked thrombocytosis (platelet counts ranging from 1003 x 10(9)/l to 2800 x 10(9)/l) and moderate leukocytosis (WBC counts from 10 x 10(9)/l to 19 x 10(9)/l). At initial examination, four of the six patients showed a few (4-9%) immature myeloid cells in the peripheral blood, and two had blood basophilia. All six patients later developed increasing leukocytosis, and two subsequently died from blast crisis and accelerated CML, respectively. In the overall series, 38 patients (45%) expressed the b2a2 type of BCR/ABL mRNA, and 46 (55%) either the b3a2 or both mRNAs. By contrast, only one of the six patients with CML of thrombocythemic onset expressed the b2a2 mRNA vs five with either b3a2 (n = 4) or both mRNA types (n = 1). The above results, in conjunction with similar data from a few previously published cases, suggest an association between the above form of CML and b3a2 type of BCR/ABL transcript.
Leukemia 1996 Jul
PMID:Chronic myeloid leukemia of thrombocythemic onset: a CML subtype with distinct hematological and molecular features? 909 6

Chronic myelogenous leukemia is a clonal proliferative disorder of pluripotent hematopoietic stem cells. Cure may be achieved by myeloablative conditioning treatment and marrow transplantation. In addition, allogeneic marrow can exert a graft-versus-leukemia effect. The graft-versus-leukemia effect may be directed against leukemia-specific antigens or against antigens on all hematopoietic cells, or it can be part of a graft-versus-host reaction. We report an informative post-transplant course of a patient with yet another leukemia-specific effect. This patient was transplanted with marrow from his HLA-identical sister in an advanced phase of CML and developed acute and chronic GVHD. After a severe pneumonia a high proportion of his metaphases in the bone marrow were male and Philadelphia chromosome negative. Later all metaphases were again female and leukemic cells could not be detected by reverse transcriptase polymerase chain reaction analysis (RT-PCR) for BCR/ABL. This course indicates that normal hematopoietic stem cells may survive intensive chemotherapy, bone marrow transplantation and GVHD. They may be recruited from a dormant state into proliferation during severe infections. In contrast, CML may be eliminated by the graft-versus-host reaction that recognizes recruited cells and spares dormant cells.
 ...
PMID:Graft-versus-host reaction spares normal stem cells in chronic myelogenous leukemia. 870 5

This review focuses on the role of the chimeric BCR/ABL gene in leukemia development. First, we discuss and update knowledge regarding the molecular biology of BCR/ABL. We then review data regarding transforming activity of BCR/ABL. Third, we discuss the complex interactions between BCR/ABL and leukemia phenotype. We conclude with a brief discussion of possible therapeutic implications of these data.
 ...
PMID:BCR/ABL and leukemia. 870 25

Myeloablative treatment followed by lymphohaematopoietic reconstitution with stem cells from umbilical cord blood (UCB) can cure children with leukaemia. The clinical experience of UCB transplantation with HLA 2- and 3-antigen mismatched siblings is rather limited and there are no reports of such patient being given UCB significantly contaminated with maternal T lymphocytes. In this study, we report our experience in treating a child with chronic myeloid leukaemia in blast crisis who was transplanted using UCB cells from mismatched sibling donor containing a significant number of maternal T cells. The patient received 1.17 x 10(8) nucleated cells/kg after conditioning with Ara-C, busulphan, TBI and cyclophosphamide. GVHD prophylaxis was with cyclosporine and an anti-CD25 monoclonal antibody. Although engraftment was somewhat slow it was complete as documented by cytogenetic analysis and DNA studies. Results of minimal residual disease monitoring by RT-PCR for the hybrid BCR/ABL gene showed no evidence of leukaemic mRNA post-transplant. Acute GVHD, skin only, developed on day +14 but promptly responded to low-dose steroids. The technique used for UCB collection may have cell contamination found. In spite of these potential disadvantages: advanced disease, HLA antigen disparate donor and significant maternal T cell contamination, the transplant was successful and at a follow-up of 14 months the child is well with no evidence of chronic GVHD. Immune naivety of cord blood and lack of immunological reactivity of maternal T cells in this context may have played a significant role in the outcome of this case.
 ...
PMID:Haploidentical cord blood transplant contaminated with maternal T cells in a patient with advanced leukaemia. 873 18

Until recently, it was impossible to identify leukemia cells making up less than 1% of a bone marrow sample, which is designated as minimal residual disease (MRD). Owing to the development of the polymerase chain reaction (PCR) MRD can be detected at the 10(-5) level by amplifying the leukemia-specific DNA rearrangement (BCR/ABL, PML/RARA etc.) or clone-specific DNA sequences (IgH chain CDR-III etc.). Here, our studies on MRD of acute lymphoblastic leukemia and acute promyelocytic leukemia are presented, and their technical problems and clinical significance are discussed.
 ...
PMID:[Detection of minimal residual leukemia using polymerase chain reaction method]. 875 31

A variant form of BCR/ABL junction was identified in a patient with chronic myelogenous leukaemia (CML). The BCR/ABL fusion mRNA of this patient showed in-frame junction between BCR exon c3 and ABL exon 2. Although the diagnosis of CML was made, the patient showed clinical features of essential thrombocythaemia (ET) rather than that of typical CML. Treatment with interferon-alpha showed no cytogenetic response. The c3-a2 type of BCR/ABL junction seems to be associated with elevated platelet count and thus could form a novel clinical entity different from typical CML.
 ...
PMID:Elevated platelet count features the variant type of BCR/ABL junction in chronic myelogenous leukaemia. 875 98

The products of the Philadelphia chromosome translocation, P210 and P190(BCR/ABL), are cytoplasmic protein tyrosine kinases that share the ability to transform hematopoietic cytokine-dependent cell lines to cytokine independence but differ in the spectrum of leukemia induced in vivo. We have analyzed the Janus kinase (JAK) and signal transducer and activator of transcription (STAT) pathways in hematopoietic cells transformed by Bcr/Abl. STAT5 and, to a lesser extent, STATs 1 and 3 were constitutively activated by tyrosine phosphorylation and induction of DNA binding activity in both P210 and P190(BCR/ABL)-transformed cells, but P190 differed in that it also prominently activated STAT6. There was low level tyrosine phosphorylation of JAKs 1, 2, and 3 in Bcr/Abl-transformed cells, but no detectable complex formation with Bcr/Abl, and activation of STAT5 by P210 was not blocked by two different dominant-negative JAK mutants. These results suggest that P210 and P190(BCR/ABL) directly activate specific STAT family members and may help explain their overlapping yet distinct roles in leukemogenesis.
 ...
PMID:P210 and P190(BCR/ABL) induce the tyrosine phosphorylation and DNA binding activity of multiple specific STAT family members. 894 Jan 93

BCR-ABL is a chimeric oncoprotein that exhibits deregulated tyrosine kinase activity and is implicated in the pathogenesis of Philadelphia chromosome (Ph1)-positive leukemia. We have previously shown SH2-containing phosphotyrosine phosphatase SHP-2 forms stable complexes with BCR-ABL and Grb2 in BCR-ABL-transformed cells (Tauchi, T., Feng, G. S., Shen, R., Song, H. Y., Donner, D., Pawson, T., and Broxmeyer, H. E. (1994) J. Biol. Chem. 269, 15381-15387). To elucidate the structural requirement of BCR-ABL for the interactions with SH2-containing signaling molecules, we examined a series of BCR-ABL mutants which include the Grb2 binding site-deleted BCR-ABL (1-63 BCR/ABL), the tetramerization domain-deleted BCR-ABL (64-509 BCR/ABL), and the SH2 domain-deleted BCR-ABL (BCR/ABL deltaSH2). These BCR-ABL mutants were previously shown to reduce the transforming activity in fibroblasts. We found that the tetramerization domain-deleted BCR-ABL did not induce the tyrosine phosphorylation of SHP-2 and the interactions of BCR-ABL, SHP-2, and Grb2. In vitro kinase assays have also shown that the tetramerization domain-deleted BCR-ABL mutant did not phosphorylate GST-SHP-2 in vitro. SHP-2 was co-immunoprecipitated with phosphatidylinositol 3-kinase in BCR/ABL p210-transformed cells; however, this interaction was not observed in the tetramerization domain-deleted BCR-ABL mutant. Therefore the tetramerization domain of BCR-ABL is essential for interactions of these downstream molecules.
 ...
PMID:A coiled-coil tetramerization domain of BCR-ABL is essential for the interactions of SH2-containing signal transduction molecules. 899 49

We have previously shown by reverse transcriptase-PCR (rtPCR) that CML CD34+ HLA-DR- cells are enriched for BCR/ABL(-) hematopoietic progenitor cells (HPC) while leukemic HPC reside predominately within CML CD34+ HLA-DR+ cells. We investigated whether the 30/35 kDa fragment of fibronectin (FN) could be used to enhance retroviral-mediated gene transfer (RMGT) in chronic phase CML marrow HPC. CML CD34+ HLA-DR- and CD34+ HLA-DR+ cells were transduced with vector supernate containing the neomycin resistance gene on plates coated with either FN or bovine serum albumin (BSA) as control, then assayed for transduced HPC in progenitor cell assays in the presence or absence of G418. Transduction efficiency of CML CD34+ HLA-DR- cells over BSA ranged from 0.09 to 7.2% (mean 3.3 +/- 1.5%), while that over FN plates ranged from 3.8 to 23% (mean 11.0 +/- 4.5%) (n = 4). Transduction efficiencies of CML CD34+ HLA-DR+ cells ranged from 0.4 to 9.8% (mean 3.7 +/- 1.7%) and 6.0 to 26% (mean 17.3 +/- 4.5%) (n = 5) over BSA and FN, respectively. rtPCR analysis for BCR/ABL mRNA of individual G418-resistant HPC generated from CD34+ HLA-DR- cells revealed that normal BCR/ABL(-) HPC were successfully transduced under these experimental conditions. These results demonstrate the feasibility of transducing normal CML primitive HPC, and illustrate the potential clinical use of FN in the setting of gene therapy for CML, as well as other diseases.
Leukemia 1997 Jan
PMID:The 30/35 kDa chymotryptic fragment of fibronectin enhances retroviral-mediated gene transfer in purified chronic myelogenous leukemia bone marrow progenitors. 900 33

The BCR/ABL oncogene product is one of the genes associated with and possibly responsible for human leukemias. Chronic myelogenous leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia are associated with p210BCR/ABL and p185BCR/ABL, respectively. Abelson murine leukemia virus encodes the related oncogene product, v-Abl, and also causes pre-B-cell leukemia. In this article, recent advances in understanding the function of these oncogenes as well as the function of normal counterparts, c-Abl and Bcr, are discussed. Intracellular signaling events initiated from these oncogene products are emphasized. The possibilities are also discussed that inhibition of apoptosis and altered adhesive properties to the bone marrow microenvironment by BCR/ABL might contribute to disease initiation.
 ...
PMID:The function of BCR/ABL and related proto-oncogenes. 905 Mar 73


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