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)

hLH-2, a transcription factor that contains double cysteine rich regions (LIM motifs) and a homeobox (Hox) DNA-binding domain shows aberrant high expression in all cases of chronic myelogenous leukemia (CML). This gene has been mapped to the chromosome 9q33-34.1, the same region as the reciprocal translocation that creates the breakpoint cluster region (BCR)-ABL chimera of the Philadelphia chromosome (Ph'). To investigate the possible involvement between the BCR-ABL fusion gene and hLH-2 in the pathogenesis of CML, an hLH-2-negative CML cell line, JK-1 that carries double Ph' chromosomes, was examined. Like other CML cells, high BCR-ABL fusion mRNA levels are expressed, but no transcript of hLH-2 was detected in JK-1 cells as determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Compared with the CML cell line, K-562, an additional rearrangement of the BCR gene was observed in JK-1 as determined by Southern blot hybridization; however, the hLH-2 gene was normal. These findings raise interesting questions about the possible roles of either the abnormal BCR gene or other genetic events such as the complex chromosomal abnormalities that result in hLH-2 being turned off in JK-1 cells.
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PMID:A structurally abnormal breakpoint cluster region gene in a transcription factor, hLH-2-negative human leukemia cell line. 760 May 33

In chronic myeloid leukemia (CML) the proto-oncogene c-abl from chromosome 9 q34 is translocated to the breakpoint cluster region (bcr) gene on chromosome 22 q11. This translocation results in a BCR-ABL fusion gene, which encodes chimeric fusion oncoproteins p210BCR-ABL. Here we demonstrate that a peptide with joining region sequence ATGFKQSSKALQRPVAS (eight amino acids (aa) encoded by BCR exon 3; one novel lysine, encoded by the fusion codon; eight aa encoded by ABL exon 2) is immunogenic to human T cells. Primary immune response induction with this peptide resulted in a HLA DR2(DRB1*1501) restricted CD4+ BCR-ABL peptide specific T cell line P1. Responses of P1 were negatively affected by individual aa replacement by alanine at eight aa positions within the 17mer peptide (F4, K5, Q6, K9, L11, Q12, R13, P14). These findings were supported by experiments with a panel of overlapping 11mer b3a2 peptides. Only two of these peptides with an aa sequence encompassing all residues which could not be replaced by alanine induced P1 proliferation. Since presentation of cytosolic oncoproteins as peptides by DR molecules has been observed, the present findings provide a possible explanation for post interferon-alpha persisting remissions in spite of the presence of BCR-ABL PCR positive progenitors.
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PMID:Recognition of peptides corresponding to the joining region of p210BCR-ABL protein by human T cells. 764 23

The BCR-ABL fusion gene is directly involved in the pathogenesis of chronic myeloid leukemia (CML). Specific inhibition of the BCR-ABL gene expression with antisense oligodeoxynucleotides has been shown to have profound effects on cell growth in vitro. We examined antisense phosphodiester oligonucleotides (16-mers at a concentration of 60 micrograms/ml) spanning the two possible junction sites K28 (b3a2) and L6 (b2a2) in a clonogenic assay. Single colonies from 9 patients with CML and from patients with normal bone marrow were screened for BCR-ABL expression with a new 'single-tube nested PCR' method. There was a marked reduction in colony number in the CML group and a lesser growth inhibition in the control group. The number and percentage of BCR-ABL-positive colonies, however, was not reduced in the CML group. This indicates a nonspecific growth inhibition only.
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PMID:Unmodified phosphodiester antisense oligodeoxynucleotides to the BCR-ABL junction do not suppress Philadelphia-positive clonogenic cells. 770 17

Two children with Ph+ chronic myelogenous leukemia (CML) relapsed in the chronic phase after allogeneic bone marrow transplantation (BMT). They were treated with transfusions of peripheral blood mononuclear cells (PBMC) obtained from the former bone marrow donors in combination with interferon alfa-2. In one child, CML was successfully controlled as shown by disappearance of Ph+ metaphases as well as negativity for BCR-ABL fusion gene transcripts demonstrated by polymerase chain reaction (PCR) analysis. The patient has remained in complete remission without evidence of disease for 12 months after donor PBMC transfusions. The other child showed disappearance of BCR-ABL gene transcripts by PCR analysis only in peripheral blood cells, but PCR positivity persisted in bone marrow samples. These results indicate that adoptive immunotherapy may be a further alternative in children with relapse of CML after allogeneic BMT as previously described for adult patients.
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PMID:Adoptive immunotransfer with viable donor mononuclear cells for recurrent chronic myelogenous leukemia after allogeneic bone marrow transplantation in two children. 770 41

By using "nested" retrotranscriptase/polymerase chain reaction (RT/PCR) technique, we determined the expression patterns of the BCR-ABL fusion gene resulting from the chromosomal translocation t (9; 22) in leukemias with Ph1 chromosome. Three distinct isoforms of fusion gene transcripts were discovered: ela2, b2a2 and b3a2. In 10 cases of chronic myelogenous leukemia (CML), only two types (b2a2 and b3a2) were observed. However, in 8 cases of Ph1 chromosome positive acute lymphoblastic leukemia (Ph1 + ALL), all three types were detected, including two cases characterized by the coexistence of ela2 and b2a2 or b3a2 types. Moreover, the RT/PCR procedure established in the present study proved to be a very sensitive method, allowing the detection of one leukemic cell among 10(5)-10(6) normal cells. Thus, a positive RT/PCR result was obtained in two Ph1 + ALL cases just after chemotherapy-induced clinical remission (CR), suggesting the presence of residual disease. One case remained RT/PCR positive four months after achieving CR and relapsed in the fifth month, while the other case converted to RT/PCR negative eight months later and is now in CR for 18 months. Therefore the detection of BCR-ABL fusion gene is of importance not only in the study of the pathogenesis of Ph1 + leukemias but also in their diagnosis and monitoring of minimal residual disease during CR.
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PMID:[Detection on BCR-ABL fusion gene in Ph1 chromosome positive leukemia by "nested" retrotranscriptase/polymerase chain reaction]. 786 99

The long-term marrow culture (LTC) system allows the sustained production of primitive normal and neoplastic (chronic myeloid leukemia [CML]) hematopoietic cells in vitro for many weeks. This is achieved in the absence of exogenously added hematopoietic growth factors because of the presence in the cultures of supportive "stromal" cells of the fibroblast-endothelial-adipocyte lineages. These latter cells form a confluent adherent layer with which the most primitive hematopoietic cells become associated and which locally regulates their behavior. The LTC system has thus been considered as a model of the microenvironment of the bone marrow and used to delineate potentially physiologically relevant mechanisms that regulate the proliferation, self-renewal and differentiation of primitive normal hematopoietic cells. It has also been used to analyze the molecular basis of the altered proliferative behavior that characterizes primitive neoplastic cells from patients with CML. Most of the information obtained to date has emerged from experiments designed to shift the balance of stimulatory and inhibitory factors present in order to favor either the cycling or quiescence of primitive normal or CML cells in LTC. This has been achieved either by addition of soluble factors (or antagonists) to the LTC medium or by the use of genetically engineered factor-producing stromal cells. Such experiments have allowed the identification of a number of cytokines that promote one or the other of these responses (i.e., primitive progenitor cycling or quiescence), including some that are involved in control mechanisms endogenous to the LTC system. Recent studies suggest that the retention of primitive normal cells in a reversible G(o) state in this system is mediated by the cooperating action of limiting concentrations of at least two endogenously produced inhibitory factors (transforming growth factor-beta (TGF-beta) and macrophage inflammatory protein-1 alpha (MIP-1 alpha)), either of which, however, if added exogenously at a sufficient concentration, can exert this action on its own. Interestingly, the heightened turnover characteristic of primitive CML cells appears to be due to a selective unresponsiveness to only one of these two inhibitors (MIP-1 alpha). These findings are consistent with a complex model of the extrinsic regulation of primitive hematopoietic cells in which a multiplicity of intracellular signaling intermediates within the target cells converge at different points ultimately to control their entry into S phase. Our findings further suggest that only some of these pathways may be affected by intracellular expression of the BCR-ABL fusion gene.
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PMID:Differential manipulation of normal and chronic myeloid leukemia stem cell proliferation in vitro. 799 64

Mutants and fusion products of the c-abl gene were used to define some of the molecular requirements for rapid plasmacytoma (PC) and pre-B-lymphoma induction in pristane-treated N-myc transgenic BALB/c mice. A-MuLV induced PCs in 21 of 25 mice with a mean post-pristane latency period of 46 +/- 9 days, compared to 134 +/- 25 days in controls exposed to pristane alone. delta XB, a mutant of type IV c-abl with a deletion of the SH3 domain, was equally effective in inducing PCs in 7 of 7 mice with a latency period of 49 +/- 7 days, indicating that gag sequences are not required for rapid PC induction. The delta XB delta Nar mutant that carried a large C-terminal deletion in addition showed only a negligible activity, if any, suggesting that PC acceleration requires the C-terminal domain in the same way as lymphoid transformation and in contrast to fibroblast transformation. BCR-ABL fusion constructs encoding an 185-kDa protein as in acute leukemia, or a 210-kDa protein as in chronic myelocytic leukemia (CML), did not accelerate pristane-induced PC development in the N-myc transgenic mice, in contrast to their known ability to immortalize lymphoid cells in vitro. Only one of 14 non-transgenic littermates developed a pre-B lymphoma after A-MuLV infection, and none of 10 normal littermates infected with delta XB virus developed a construct-carrying tumor. This result suggests that PC acceleration is due to co-operative interaction of the N-myc transgene and activated abl. Infection of N-myc transgenic bone marrow or spleen cells with A-MuLV in vitro led to the outgrowth of pre-B lymphomas after transplantation to pristane-treated BALB/c recipients. The lymphoma-inducing activity of A-MuLV depends on its high titer, since diluted A-MuLV or the lower-titered delta XB induced only PCs under the same conditions. The v-abl, delta XB and BCR-ABL-carrying viruses generated immortalized lymphoblastoid lines in vitro, regardless of the presence of the N-myc transgene, suggesting that lymphoid transformation is a direct function of appropriate abl sequences in contrast to PC acceleration.
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PMID:Molecular requirements for rapid plasmacytoma and pre-B lymphoma induction by Abelson murine leukemia virus in myc-transgenic mice. 801 9

The BCR-ABL translocation of chronic myelogenous leukemia represents a paradigm for the study of translocations that create fusion proteins. The work of many laboratories has clearly established that the BCR-ABL protein can transform cells and cause leukemias in mice. This oncogenic signal appears to involve transduction of a tyrosine kinase signal from the cytoplasm to the nucleus via intermediary proteins such as ras and myc. Although the biological effects of the BCR-ABL fusion protein are well characterized, the normal biological functions of ABL and BCR are only beginning to come to light. ABL is a nuclear tyrosine kinase which binds DNA, suggesting a possible normal role in transcription. BCR has homology to proteins which regulate membrane ruffling. Understanding the normal roles of ABL and BCR will help define the abnormal leukemogenic effects of the BCR-ABL fusion.
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PMID:Molecular consequences of the BCR-ABL translocation in chronic myelogenous leukemia. 812 22

The presence of BCR-ABL fusion genes has important diagnostic and prognostic implications in chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL). The CML-specific chimeric BCR-ABL gene with a break involving the major breakpoint cluster region (M-bcr) of the BCR-gene has been detected by means of fluorescence in situ hybridization (FISH). In this study, we present a FISH protocol that allows the detection of breaks in both the major and the minor breakpoint cluster region (m-bcr). Three hybridization signals of D107F9, a yeast artificial chromosome (YAC)-derived probe spanning the breakpoint regions of the BCR gene, were indicative of the translocation events. To increase the specificity further, this probe was combined with cos-abl 8, a cosmid probe flanking the breakpoint within the ABL gene for dual-color hybridization. Samples of 21 patients with CML, the ALL-derived cell line SUP-B15, and of seven patients with Philadelphia chromosome (Ph1)-positive ALL (three of them with breakpoints within m-bcr) were examined. BCR-ABL fusion was detected in all cases with high specificity (false-positive nuclei: mean, 0.1%). On cytogenetic preparations, the percentages of BCR-ABL-positive interphase cells ranged from 53% to 91%. Comparable efficiencies were achieved on blood smears. In conclusion, hybridization with D107F9 and cos-abl 8 allows unambiguous diagnosis of BCR-ABL genes and is likely to become an important tool for the monitoring of therapies in patients with CML and ALL.
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PMID:Detection of chimeric BCR-ABL genes on bone marrow samples and blood smears in chronic myeloid and acute lymphoblastic leukemia by in situ hybridization. 814 58

Chronic myeloid leukemia (CML) has long served as a prototype malignancy for basic as well as clinical studies aimed at developing curative cancer treatment protocols. Well established features of chronic phase CML are its origin in a pluripotent stem cell, a now well defined molecular genetic basis involving the creation of a BCR-ABL fusion gene and evidence of resultant abnormalities in the mechanisms that normally control primitive hemopoietic cell proliferation. We have recently shown how the long-term marrow culture system can be adapted to quantitate and characterize a very primitive cell type in normal blood and marrow samples, as well as their normal and leukemic counterparts in patients with CML. This system has also been used to dissect mechanisms of normal progenitor regulation and to identify specific anomalies affecting leukemic (CML) progenitors. Our studies show that cells detected by their ability to initiate long-term cultures (LTC) of leukemic cells (i.e., CML LTC-initiating cells or LTC-IC) are differently distributed between marrow and blood by comparison to LTC-IC in normal individuals and, although functionally similar in terms of the number and differentiation types of clonogenic cells they produce, CML LTC-IC exhibit defective self-maintenance. Phenotypically these primitive leukemic cells are heterogeneous; the majority display features of activated/proliferating cells but a significant proportion do not. We have also documented heterogeneity in primitive CML cell responses to two factors that specifically and reversibly arrest the cycling of primitive normal hemopoietic cells; i.e., TGF-beta and MIP-1 alpha, to which CML cells are normally responsive and abnormally unresponsive, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The biology of normal and neoplastic stem cells in CML. 825 4


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