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)

More than 95% of the patients with chronic myelogenous leukemia (CML) carry translocations between protooncogene abl of chromosome 9 and bcr gene of chromosome 22, resulting in the Philadelphia chromosome (Ph1). After allogeneic bone marrow transplantation (BMT) it is important to detect possible residual malignant cells in CML patients. A new sensitive hybridization method combined with polymerase chain reaction (PCR), based on the detection of the europium (Eu3+) label by time-resolved fluorescence, was applied for the detection of Ph1 chromosome. Total RNA from 10(6) peripheral blood leukocytes was isolated by the acid guanidinium thiocyanate-phenol-chloroform extraction. After cDNA synthesis by reverse transcriptase, the PCR amplification (30 cycles) was carried out. In the detection phase two oligonucleotide probes were used in the hybridization reaction, one biotinylated (bcr gene, exon 2) and one (abl gene) labeled with Eu3+. The hybrids were collected in a streptavidin-coated microtitration well and the bound Eu3+ was measured in a time-resolved fluorometer. To assess the sensitivity of the method, different numbers of CML cell line K562 cells were mixed with 10(5) apparently normal human leukocytes. Five K562 cells/10(5) leukocytes could be detected. Six patients with CML confirmed by clinical and cytogenetic criteria were studied. Three of the patients underwent an allogeneic BTM 6-18 months before the investigation and all of them were Ph1-negative. The other three patients who were nontransplanted were positive as expected.
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PMID:Detection of Philadelphia chromosome using PCR and europium-labeled DNA probes. 786 15

We sequentially analyzed the immunoglobulin heavy chain variable (IgH V) region gene of leukemia cells obtained from a chronic myeloid leukemia (CML) patient who had three episodes of B-lymphoid crisis after bone marrow transplantation. Southern blot analysis using the JH probe showed different rearranged bands at each crisis, although the same rearranged bands of the BCR gene were observed. We amplified and sequenced the IgH V region gene of the leukemia cells by reverse transcriptase polymerase chain reaction (RT-PCR) using the primers corresponding to the consensus 5'VH and mu constant regions. The dominant leukemia clone at each crisis had a unique VH-D-JH rearrangement; VH4A (V79)-DLR2-J5 (clone-1), VH4B (DP70)-DK4-J6 (clone-2) and VH4A (V79)-DN4-J6 (clone-3) at the first, second and third crises, respectively. Further analysis by PCR amplification using the consensus 5'VH and clone-specific primers revealed that clone-1 underwent VH4-->VH3 replacement at the second crisis, and that clone-3 was already in existence at the first crisis. Moreover, the DN4-J6 joining clone, in which the sequence was the same as that of clone-3, was identified at the first and third crises by PCR amplification using primers corresponding to the region upstream of the DN4 segment and DN4-J6 boundary of clone-3. These observations suggest that multiple clones were generated from the progenitor cells of blast crisis, which were transformed at a very early stage of B-lymphocyte ontogeny, by continuing rearrangement mechanisms of the IgH genes, and that the dominant clone at each crisis was undergoing change.
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PMID:Continuing immunoglobulin heavy chain gene rearrangements in chronic myeloid leukemia with recurrent B-lymphoid blast crises after bone marrow transplantation. 786 62

Seventy months after diagnosis, minimal residual disease is undetectable in a patient with Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in long-lasting continuous cytogenetic conversion (CCC), achieved through alpha 2a-interferon (IFN-alpha) therapy. Fluctuating molecular remission, evaluated with the two-stage reverse transcriptase-polymerase chain reaction (RT-PCR) with nested primers, has persisted for two years at the maximum tolerable dose of IFN alpha (1.5 x 10(6) IU per day).
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PMID:Interferon-alpha 2a therapy in CML: disappearance of BCR/ABL transcript in a case of long-lasting continuous cytogenetic conversion. 789 13

With the recent advances in molecular technology, diagnostic procedures of the diseases at a DNA level have been introduced in hematological fields. The diagnostic methods used are Southern blotting to detect gene rearrangements, Northern blotting to find gene expressions, RT-PCR (reverse transcriptase-polymerase chain reaction) to identify transcribed fusion messages, and PCR-SSCR (single strand conformation polymorphism) to detect mutated genes. Rearrangements within major Bcr (breakpoint cluster region) were observed in almost all cases in chronic myelogenous leukemia, and breakpoint were found within minor Bcr in Philadelphia-positive leukemia. The rearrangements within the second intron of the retinoic acid receptor-alpha and sixth intron (bcr 1), third intron (bcr 3) and sixth exon (bcr 2) of the PML gene were detected in all cases with acute promyelocytic leukemia. In malignant lymphoma, the rearrangements of immunoglobulin and T-cell receptor genes, and new genes such as Bcl-1, Bcl-2, Bcl-5, Tal-1, and Tal-2 were also reported and rearrangements of the Bcl-5 gene were found in this study using Bcl-5 specific probe which we have cloned. Point mutations and deletions of the genes involved in the coagulation and fibrinolysis system have been reported. One base insertion resulting in elongation of carboxy terminal region and one amino acid deletion in alpha 2-plasmin inhibitor gene were found in two cases of its deficiency. Further study revealed that mutated proteins were retained in the endoplasmic reticulum in the cells. With the development of the PCR method, identification of gene mutation is gradually carried out as a routine work.
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PMID:[Molecular study of hematological diseases]. 791 42

Interferon-alpha induces durable cytogenetic remissions in about one-quarter of newly diagnosed patients with chronic myelogenous leukemia (CML). Even so, after short-term follow-up, previous studies have shown that residual leukemic cells can be detected by the polymerase chain reaction (PCR) in all of these individuals. The objectives of our study were therefore to obtain long-term follow-up data on residual disease in a cohort of complete responders and to determine if leukemic cells with clonogenic potential are present in patients despite the absence of relapse. We performed (a) serial analysis of blood and/or bone marrow for a reverse transcriptase PCR amplified BCR-ABL transcript at times well beyond the point that cytogenetic remission was first attained and (b) reverse transcriptase PCR of individually plucked myeloid and erythroid colonies for the presence of the same transcript. Seven CML patients who had previously attained complete cytogenetic remission while on interferon-alpha were investigated. Six of the seven patients were in complete cytogenetic remission at the time of analysis, whereas one patient had early evidence of cytogenetic relapse. With ongoing therapy, five patients with the longest follow-up eventually achieved PCR negativity at time periods of 27, 32, 36, 49, and 67 mo after a complete cytogenetic remission was first noted. Even so, residual disease was detected in progenitor cells derived from two patients, each of whom had been in continuous cytogenetic remission for approximately 2.5 and 3.5 yr, respectively. Progenitors expressing BCR-ABL transcripts were also detected in the patient with early cytogenetic relapse. These observations demonstrate that residual disease resides in colony-forming cells that should have the potential to repopulate the bone marrow. However, the presence of a minority of Ph-positive CML progenitor cells for a very long period of time is still compatible with durable remission, confirming that a situation of tumor dormancy may be induced in CML by interferon therapy.
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PMID:Persistence of dormant leukemic progenitors during interferon-induced remission in chronic myelogenous leukemia. Analysis by polymerase chain reaction of individual colonies. 792 13

We describe the polymerase chain reaction (PCR) method using stained bone marrow smears as sources of RNA. The amount of extractable RNA decreased during the process of making and staining bone marrow smears. The sensitivity of the reverse transcriptase-based polymerase chain reaction (RT-PCR) method for detecting target mRNA-positive cells in 5 x 10(5) suspended cells and stained bone marrow smears were 1:10(5) and 1:5000, when we used K562 cells. The bone marrow smears of 21 patients with chronic myelogenous leukemia (CML) were examined using this method. We extracted RNA from stained specimens stored at room temperature for 5-14 years. Twelve of 21 (57%) smears showed positive results for bcr/abl. The carrier RNA improved the recovery when added at the step of RNA extraction. These data indicate that mRNA is present in stained bone marrow smears for at least 14 years and that the sensitivity of RT-PCR is adequate for molecular analysis.
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PMID:Detection of bcr/abl mRNA in stained bone marrow smears. 788 52

The in vitro sensitivity of human chronic myeloid leukemia-blast crisis and chronic phase (CML-BC and CML-CP, respectively) cells as well as adherent cell-depleted, T lymphocyte-depleted normal bone marrow cells (A-T-NBMC) to various concentrations of mafosfamide (ASTA Z7654), was examined by colony formation assay in the presence of IL-3 and GM-CSF, to test the possibility of purging of BMC from CML cells. Colony formation by CML cells was inhibited more efficiently than by NBMC. After the incubation with 50 micrograms/ml or 100 micrograms/ml of mafosfamide, the growth of leukemic CFU-GM was totally abrogated in 2/11 or 9/11 cases of CML-BC and in 1/7 or 6/7 cases of CML-CP, respectively. At the same time the CFU-GM arising from normal BMC were not inhibited totally with 50 or 100 micrograms/ml of the drug in any of five experiments. CML cells were still unable to form secondary colonies, while normal BMC were capable of regrowth. The CD34+ cells isolated form CML-BC and CML-CP patients were also more susceptible to mafosfamide cytotoxicity in comparison to CD34+ cells derived from NBMC. To confirm the possibility of purging, CML-BC cells were mixed with NBMC (1:1) and incubated with mafosfamide. Finally, the growing colonies were examined for the presence of bcr/abl hybrid gene by reverse transcriptase-Taq polymerase chain reaction (RT-PCR) and specific hybridization. The bcr/abl gene was not detected in the colonies growing after 100 micrograms/ml, and the signal was diminished after incubation with 50 micrograms/ml of mafosfamide, as compared to control. These results strongly suggest that high concentrations of mafosfamide may be useful for the purging of autologous BMC from CML cells.
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PMID:Successful mafosfamide purging of bone marrow from chronic myelogenous leukemia (CML) cells. 813 96

Recent studies suggest that the BCR-ABL gene plays a critical role in the pathogenesis of Ph+ chronic myeloid leukemia (CML). We investigated the hematopoietic colonies derived from the marrows of 12 patients with Ph+ CML in chronic phase by reverse transcriptase-polymerase chain reaction (RT-PCR) amplification of BCR-ABL mRNA and by cytogenetics. Colonies were individually harvested and each colony divided into two portions, one for cytogenetics and the other for isolation of total RNA for PCR of BCR-ABL transcripts and for an RNA internal control. We found that 23% +/- 18% (mean +/- SD, range 0% to 60%) of Ph+ colonies did not transcribe the aberrant gene. In each case when BCR-ABL transcription was not detected, normal ABL mRNA was present. The data suggest that hitherto unknown mechanisms may regulate BCR-ABL expression in some Ph+ cells and indicate that caution should be exercised in the interpretation of results using RT-PCR analysis of hematopoietic colonies from clinical specimens and from experiments with antisense oligonucleotides directed at the BCR-ABL gene. These data also raise the notion of a transitional Ph+ precursor cell in which BCR-ABL may become upregulated and lead to a fully expressed phenotype. We conclude that further studies correlating the frequency of Ph+ PCR- progenitors with prognostic clinical variables are warranted.
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PMID:Variable transcription of BCR-ABL by Ph+ cells arising from hematopoietic progenitors in chronic myeloid leukemia. 794 97

Various kinds of nonrandom chromosomal aberrations have been reported in hematopoietic malignancies. Since the 1980s, many translocation-associated oncogenes and several suppressor oncogenes have been identified and applied for the clinical diagnosis of these malignancies. The former is of major, clinical importance for specific diagnosis made on the basis of molecular detection of the chromosomal translocation, the deregulated expression, and the chimeric mRNA of those genes. Both BCL-1 and BCL-2 genes, associated with mantle zone lymphoma and follicular lymphoma, respectively, belong to the representative deregulated oncogenes by juxtaposition with an immunoglobulin gene enhancer as well as an MYC gene in Burkitt's lymphoma. On the other hand, the MLL gene, associated with infant leukemia, acute monocytic leukemia and secondary leukemia, produces chimeric mRNAs between LTG4, 9, and 19 genes as well as the BCR-ABL chimeric gene in chronic myelogenous leukemia. The detection of minimal residual disease (MRD) by either polymerase chain reaction (PCR) or reverse transcriptase (RT)-PCR is becoming an essential test during the course of treatment containing bone marrow transplantation, because positive results of the MRD are closely related to poor prognosis and would have great influence on the choice of treatment plans.
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PMID:[Molecular diagnosis of leukemia and lymphoma]. 817 45

The reverse transcriptase-polymerase chain reaction (RT-PCR) for BCR-ABL mRNA is increasingly used to diagnose and monitor patients with Ph+ chronic myeloid leukemia (CML). We investigated an alternative approach to detect BCR-ABL mRNA in CML in order to overcome some of the potential drawbacks of RT-PCR. Nucleic acid sequence based amplification (NASBA) is a homogeneous, isothermal, in vitro process that provides the direct amplification of RNA. Peripheral blood from seven patients with Ph+ CML and Ph+ EM-2 cells were investigated by NASBA and RT-PCR. A nested set of four primers flanking the BCR-ABL junction was used in two serial NASBA reactions performed for 2 hours. The two methods were fully concordant for detection of transcripts with bcr3-abl2 and bcr2-abl2 junctions. Ethidium bromide fluorescence with NASBA indicated in repeated experiments that similar quantities of total RNA from patient material contained different amounts of BCR-ABL mRNA. The data suggest that direct amplification of RNA is suitable for identifying and monitoring patients with Ph+ CML and may provide a means to quantify BCR-ABL mRNA levels.
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PMID:Detection and direct sequence identification of BCR-ABL mRNA in Ph+ chronic myeloid leukemia. 824 71


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