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)

Current evidence suggests that the expression of the tyrosine kinase p210bcr/abl in chronic myelogenous leukemia (CML) may directly induce the initial phase of granulocytic hyperplasia. However, the dysregulation of additional genes appears to be required for transition to the acute leukemic phase, as inferred by the appearance of recurrent secondary cytogenetic abnormalities in the majority of patients. To determine whether the expression of p210bcr/abl alone is responsible for this genetic instability, we introduced and expressed the bcr/abl gene from a retroviral vector in a clone of the interleukin-3 (IL-3) dependent myeloblastic 32D C13(G) cell line. Clonal and polyclonal cells transformed to IL-3 independent growth were observed for a period extending up to 6 months for changes in the expression of p210bcr/abl, cell proliferation, inhibition by prostaglandin E1 (PGE1), forskolin, and cyclic adenosine monophosphate (cAMP) analogues, regulation of the cell cycle, and karyotype. Whereas the properties of control vector infected 32D C13(G)' cells remained stable over time, cells expressing p210bcr/abl were phenotypically unstable. In cells expressing p210bcr/abl, we observed selective modulation of p210bcr/abl mRNA and protein expression, evolution from partial to full abrogation of IL-3 dependence, reduced serum requirements, increased cell proliferation, decreased inhibition by PGE1 and cAMP analogues, and the appearance of new structural and numerical chromosomal abnormalities with successive cell passages. These results indicate that expression of p210bcr/abl can directly predispose 32D C13(G)' cells to genetic instability, promotes the emergence of clones with an increased proliferative advantage, and may represent an in vitro model suitable for the study of mechanisms underlying progression to the acute leukemic phase in CML.
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PMID:Clonal evolution in a myeloid cell line transformed to interleukin-3 independent growth by retroviral transduction and expression of p210bcr/abl. 132 83

The involvement of the BCRlABL fusion gene in patients with Philadelphia (Ph) chromosome positive chronic myeloid leukaemia (CML) and acute lymphoblastic leukaemia (ALL) is well characterised, but the molecular events underlying the cases of Ph-negative CML and ALL that lack BCR gene involvement and those that cause transformation of Ph-positive CML are unknown. The murine ABL gene can be activated by genetic events that do not involve the BCR gene, including the introduction of two specific point mutations in exons VII and XI respectively, as found in the homologous sequence of the v-abl oncogene. We therefore sought evidence for analogous point mutations in the ABL gene in patients with Ph-negative, BCR-negative CML (n = 25), Ph-negative ALL (n = 18) and in Ph-positive CML in transformation (n = 28). We used restriction fragment length polymorphism and single strand conformational polymorphism techniques to analyse DNA amplified fragments of selected ABL coding regions from leukaemia cells. We identified only normal wild-type DNA sequences. The absence of these transforming point mutations does not exclude the possibility that the ABL gene in such patients could be activated by other means.
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PMID:Specific point mutations that activate v-abl are not found in Philadelphia-negative chronic myeloid leukaemia, Philadelphia-negative acute lymphoblastic leukaemia or blast transformation of chronic myeloid leukaemia. 135 50

Chronic myelogenous leukemia (CML) is a lethal malignancy of the human hematopoietic stem cell. Here we report that coexistent benign, primitive hematopoietic progenitors can be distinguished from their malignant counterparts in CML bone marrow by differences in cell surface antigen expression. Selection of bone marrow cells expressing the CD34 antigen but lacking the HLA-DR antigen results in recovery of small lymphocyte-like blasts, which initiate and sustain production of myeloid clonogenic progeny in vitro. Secondary clonogenic cells derived at week 1, 5, and 8 from long-term bone marrow cultures (LTBMCs) initiated with primitive progenitors, which lack HLA-DR antigens, exhibit neither the Philadelphia chromosome (Ph1) nor the corresponding bcr/abl mRNA characteristic of CML. In contrast, clonogenic cells recovered at week 1, 5, and 8 from LTBMCs initiated with the CML HLA-DR+ population contain Ph1 and express bcr/abl mRNA. This observation indicates that it may be possible to select a population of viable, exclusively benign hematopoietic stem cells from CML bone marrow capable of repopulating the hematopoietic compartment following autologous bone marrow transplantation.
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PMID:Selection of benign primitive hematopoietic progenitors in chronic myelogenous leukemia on the basis of HLA-DR antigen expression. 137 Oct 77

A method is reported for conjugating an analog of 4'-(aminomethyl)-4,5',8- trimethylpsoralen to methylphophonate oligonucleotides. This method enables the psoralen moiety to be coupled to the phosphonate backbone between any two desired bases in a sequence. When hybridized to a target mRNA, the psoralen moiety can be directed toward a uridine base and, in turn, can undergo a photo-addition reaction with the target under UV irradiation at 365 nm. Several different non-nucleotide-based amino-linker reagents have been prepared for incorporation into methylphosphonate oligonucleotides by standard phosphonamidite chemistry. In addition, an N-hydroxysuccinimide activated ester analog of 4'-[(3-carboxypropionamido)methyl]-4,5',8- trimethylpsoralen has been synthesized for conjugation to the amino-linker moieties. Using this approach, we have prepared a number of psoralen-methylphosphonate-oligonucleotide conjugates which are complementary to the chimeric bcr/abl mRNA associated with chronic myelogenous leukemia. Solution hybridization studies with a 440-base subfragment of the bcr/abl RNA have shown that the psoralen moiety does not adversely affect duplex stability. Polyacrylamide gel electrophoresis analyses have demonstrated that the psoralen-oligonucleotide conjugates undergo photo-addition to the RNA in a sequence-specific manner. Optimal photo-addition occurs when the psoralen moiety is inserted adjacent to one or more adenine residues in the oligonucleotide sequence, particularly between adenine and thymine (5'-3'). This internal labeling approach greatly increases the number of potential target sites available for photo-cross-linking experiments.
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PMID:A non-nucleotide-based linking method for the preparation of psoralen-derivatized methylphosphonate oligonucleotides. 142 Apr 36

Herbimycin A, a benzoquinoid ansamycin antibiotic, was demonstrated to decrease intracellular phosphorylation by protein tyrosine kinase (PTK). In Philadelphia chromosome (Ph1)-positive leukemias such as chronic myelogenous leukemia (CML) and Ph1-positive acute lymphoblastic leukemia (ALL), both of which express bcr-abl fused gene products (P210bcr-abl or P190bcr-abl protein kinase) with augmented tyrosine kinase activities, herbimycin A markedly inhibited the in vitro growth of the Ph1-positive ALL cells and the leukemic cells derived from CML blast crisis. However, the same dose of herbimycin A did not inhibit in vitro growth of a broad spectrum of Ph1-negative human leukemia cells, and several other protein kinase antagonists also displayed no preferential inhibition. Furthermore, we demonstrated that herbimycin A has an antagonizing effect on the growth of transformed cells by a transfection of retroviral amphotrophic vector expressing P210bcr/abl into a murine interleukin (IL)-3-dependent myeloid FDC-P2 cell line. This inhibition was abrogated by the addition of sulfhydryl compounds, similar to the reaction previously described for Rous sarcoma virus transformation. The inhibitory effect of herbimycin A on the growth of Ph1-positive cells was associated with decreased bcr/abl tyrosine kinase activity, but no decrease of bcr-abl mRNA and protein, suggesting that the inactivation of bcr-abl tyrosine kinase activity by herbimycin A may be induced by its binding to the bcr-abl protein portion that is rich with sulfhydryl groups. The present study indicates that herbimycin A is a beneficial agent for the investigation of the role of the bcr-abl gene in Ph1-positive leukemias and further suggests that the development of agents inhibiting the bcr-abl gene product may offer a new therapeutic potential for Ph1-positive leukemias.
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PMID:Effect of herbimycin A, an antagonist of tyrosine kinase, on bcr/abl oncoprotein-associated cell proliferations: abrogative effect on the transformation of murine hematopoietic cells by transfection of a retroviral vector expressing oncoprotein P210bcr/abl and preferential inhibition on Ph1-positive leukemia cell growth. 151 46

Chronic myelogenous leukemia (CML) is characterized by a translocation involving the c-abl protein-tyrosine kinase gene. A chimeric mRNA is formed containing sequences from a chromosome 22 gene (bcr) at its 5' end and all but the variable exon 1 of c-abl sequence. The product of this mRNA, p210bcr-abl, has constitutively high protein-tyrosine kinase activity. We examined K562 cells and other lines established from CML patients for the presence of phosphotyrosine (P-Tyr)-containing proteins which might be p210bcr-abl substrates. Two-dimensional gel separation of 32P-labeled proteins followed by phosphoamino acid analysis of 25 phosphoproteins, which comprised the major alkali-stable phosphoproteins, indicated that three related proteins of 41 kDa are the most prominent P-Tyr-containing proteins detected by this method. The 41-kDa phosphoproteins are found in two other CML lines that we examined but not in lines of similar lineage isolated from patients with distinct leukemic disease. A protein that comigrates with the major form of pp41 (pp41A) and contains P-Tyr is also found in murine fibroblasts and B-lymphoid cells transformed by Abelson murine leukemia virus, which encodes the v-abl protein, and in platelet-derived growth factor-treated fibroblasts, in which it has been described previously. We analyzed three pairs of Epstein-Barr virus-immortalized B-cell lines from individual CML patients and found that only the lines in which active p210bcr-abl was present contained detectable pp41. We also performed immunoblotting with anti-P-Tyr antibodies on the same CML cell lines and detected at least four other putative substrates of p210bcr-abl, which were undetected with use of the two-dimensional gel technique.
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PMID:A 41-kilodalton protein is a potential substrate for the p210bcr-abl protein-tyrosine kinase in chronic myelogenous leukemia cells. 154 12

Herbimycin A, a specific tyrosine kinase inhibitor, induced erythroid differentiation of human myelogenous leukemia K562 cells with a high level of bcr/abl tyrosine kinase. Several derivatives of herbimycin A were synthesized and their effects on cell proliferation and differentiation of K562 cells were examined. Of the compounds tested, 19-allylaminoherbimycin A was the most effective in inducing differentiation of K562 cells. However, the parent compound was the most potent growth inhibitor, suggesting that chemical modification of herbimycin A reduces the growth-inhibiting activity. The sensitivities of K562 cells to herbimycin derivatives were different from those of a rat kidney cell line infected with Rous sarcoma virus (v-src), suggesting that bcr/abl kinase may differ in sensitivity from other tyrosine kinases. These results indicate that a specific inhibitor of bcr/abl kinase could be an effective antitumor agent against chronic myelogenous leukemia.
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PMID:Effects of herbimycin A derivatives on growth and differentiation of K562 human leukemic cells. 156 67

Thirty three patients with chronic myelogenous leukemia (CML) treated by allogeneic bone marrow transplantation (BMT) were evaluated for bcr/abl mRNA using the reverse transcriptase-polymerase chain reaction (RT-PCR). The bcr/abl mRNA was detected in 22 out of 33 patients in clinical complete remission after BMT. The bcr/abl mRNA was present only transiently in 6 patients. It was speculated that leukemia cells were not eradicated by conditioning therapy of BMT, but patients maintained clinical complete remission due to GVL (graft versus leukemia) effect. Further study is necessary to estimate the clinical value of this technique to predict the outcome in CML patients.
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PMID:[Molecular analysis of bcr/abl mRNA in chronic myelogenous leukemia after bone marrow transplantation by using RT-PCR method]. 160 6

The polymerase chain reaction (PCR) has become a standard method for highly sensitive detection of the bcr/abl rearrangement in patients with chronic myelogenous leukemia (CML) or acute lymphoblastic leukemia (ALL). The exquisite sensitivity of the PCR facilitates the detection of residual leukemic cells after chemotherapy or after bone marrow transplantation. However, the detection of minimal residual disease does not yield any information on the malignant potential of the bcr/abl-rearranged cells. Qualitative PCR is therefore of limited prognostic value in the monitoring of residual leukemia. We have adapted the PCR for quantitative evaluation of cells carrying the bcr/abl rearrangement and by means of two exemplary cases of CML patients after bone marrow transplantation and under treatment with alpha-interferon, respectively, we show that this new technique is suitable for the long term follow-up of the activity of the residual bcr/abl rearranged clone. Longitudinal monitoring of residual disease by the technique presented provides a novel tool for detection of incipient relapse at a very early stage.
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PMID:Monitoring of residual disease in chronic myelogenous leukemia by quantitative polymerase chain reaction. 160 87

Eight cases of Philadelphia positive acute leukemia (Ph+AL) were compared with 13 cases of Ph+ chronic myelogenous leukemia in blast crisis (BC) and 10 cases of Ph negative acute lymphoblastic leukemia (Ph-ALL) based on the clinical and molecular biological findings. Distinguishing clinical features were a high leukocyte count (median; 147.9 x 10(3)/microliters) for Ph+AL, and a high incidence of tumor formation and basophilia for BC. A cytogenetic study demonstrated the disappearance or marked reduction of Ph+ metaphases in Ph+AL in remission, while Ph+ cells persisted in BC. The major bcr gene was not rearranged in 4 Ph+AL cases, whereas it was found rearranged in 4 other cases of Ph+ AL and 6 cases of BC. Reverse transcriptase polymerase chain reaction technique demonstrated the presence of minor bcr/abl mRNA in the former three cases, and major bcr/abl mRNA in the latter 4 cases. Remission rates were 63% for Ph+AL, 38% for BC, and 100% for Ph-ALL, and the 50% survival were 12, 5 and 29 months, respectively. It was concluded that Ph+AL can be differentiated from BC by a marked reduction of Ph+ cells at remission, and that the prognosis of Ph+AL is better than BC, but worse than Ph-ALL.
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PMID:[Clinical and molecular biological study of Ph positive acute leukemia: comparison with blast crisis of chronic myelogenous leukemia and Ph negative acute lymphoblastic leukemia]. 163 16


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