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)

We describe the cytogenetic, fluorescence in situ hybridization (FISH), and molecular findings in a patient who developed a typical chronic lymphocytic leukemia (CLL) 20 months after the diagnosis of a Philadelphia (Ph)-positive chronic myeloid leukemia. Unstimulated bone marrow culture showed a 46,XX,t(9;22)(q34;q11) karyotype, and interphase FISH detected the presence of a BCR/ABL fusion signal in 13% of cells. On stimulated bone marrow culture, a normal karyotype and a 13q14 deletion by interphase FISH with D13S319 probe in 14% of the cells were found. Molecular studies detected the chimeric BCR/ABL messengers by nested reverse-transcriptase polymerase chain reaction. The B-cellular clone was documented by the presence of a clonal heavy chain immunoglobulin rearrangement. The coexistence of these two hematologic malignancies leads to questions about their cell(s) of origin. We provide evidence that CLL arose in a Ph-negative clone. The implications of these findings are discussed.
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PMID:Chronic lymphocytic leukemia developing in a patient with chronic myeloid leukemia: evidence of distinct lineage-associated genomic events. 1608 Sep 61

Kinase domain receptor (KDR) and Semaphorin3 (Sema3) have a functional relationship and are expressed in human bone marrow (BM). We cultured in vitro bone marrow stromal cells (BMSCs) and collected nonadherent cells from patients with acute myeloid leukemia (AML), chronic myelogenous leukemia (CML), acute lymphoblastic leukemia (ALL) and normal individuals. Reverse transcriptase polymerase chain reaction enzyme-linked immunosorbent assay (RT-PCR-ELISA) was performed to examine KDR and Sema3 genes expression, using beta2 microglobulin as an internal reference. KDR expression ratio in normal control BMSCs (97.0%, 32/33) was higher than in its corresponding nonadherent cells (70.8%, 17/24). KDR expression levels in ALL BMSCs and AML nonadherent cells were significantly higher than in normal controls. Sema3 expression ratios in nonadherent cells from AML (78.6%, 11/14) and CML (71.4%, 10/14) were both significantly lower than in normal control (100%, 27/27), its expression levels were also significantly lower than in normal control. Sema3 expression level in normal BMSCs was significantly lower than in nonadherent cells. Sema3 and KDR genes expression levels displayed a significantly positive correlation in normal control and ALL nonadherent cells (r=0.703, P=0.002; r=0.999, P=0.001). These results suggests that KDR may play a critical role in sustaining the hematopoietic microenvironment due to its high expression, and that KDR may be involved in pathogenesis of AML and ALL. Sema3 could also sustain the survival of hematopoietic cells with its high expression, while Sema3 gene expression may be inhibited in AML and CML.
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PMID:KDR and Sema3 genes expression in bone marrow stromal cells and hematopoietic cells from leukemia patients and normal individuals. 1608 43

RNA interference (RNAi), a posttranscriptional gene silencing process mediated by small double-stranded RNA specifically complementary to the targeted transcript, has been used extensively in the development of novel therapeutic approaches against various human diseases including chronic myelogenous leukemia (CML). Here, we report the successful construction of a tetracycline-controlled siRNA in CML cell line K562. A K562 cell line stably expressing the reverse tetracycline-controlled transactivator (rtTA) was constructed. A tetracycline responsive element (TRE) was integrated into the RNA polymerase III promoter region of pBS/U6 that was used to drive specific siRNA to target the novel cytokine receptor-like factor 3 (CRLF3) gene. The results show that rtTA was able to recognize the TRE to prevent siRNA-mediated exogenous and endogenous CRLF3 gene repressions. Moreover, CRLF3-siRNA mediated gene repression could be induced in a dose-dependent manner in the presence of doxycycline. Thus, the inducible siRNAi system in K562 cells might be useful for the study of RNAi-mediated therapeutic approaches against CML.
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PMID:Establishment and utilization of a tetracycline-controlled inducible RNA interfering system to repress gene expression in chronic myelogenous leukemia cells. 1633 30

The unique molecular characteristic of chronic myeloid leukemia (CML), the disease-causing ABL (9q34) to BCR (22q11) translocation, has provided an invaluable tool for disease diagnosis and monitoring of treatment response. The traditional standard in this regard is bone marrow karyotype, also known as conventional cytogenetics (CC), which reveals a shortened chromosome 22, the Philadelphia chromosome, t(9;22)(q34;q11). CC in CML has also been effectively used for monitoring the response to drug therapy. However, this particular laboratory test misses submicroscopic BCR/ABL translocations and is suboptimal for minimal residual disease (MRD) assessment. Both fluorescence in situ hybridization (FISH) and reverse-transcriptase polymerase chain reaction (RT-PCR) feature higher sensitivity in terms of both diagnosis and MRD assessment in CML, compared to CC. Another advantage of these alternative tests is their effective applicability to peripheral blood specimens. The current review highlights the practical literature with respect to the use of FISH for CML whereas the use of RT-PCR has been extensively covered in recent communications.
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PMID:Fluorescent in situ hybridization in the diagnosis, prognosis, and treatment monitoring of chronic myeloid leukemia. 1639 61

Imatinib mesylate (STI571), a specific Bcr-Abl inhibitor, has shown a potent antileukemic activity in clinical studies of chronic myeloid leukemia (CML) patients. Early prediction of response to imatinib cannot be anticipated. We used a standardized quantitative reverse-transcriptase polymerase chain reaction (QRT-PCR) for BCR-ABL transcripts on 191 out of 200 late-chronic phase CML patients enrolled in a phase II clinical trial with imatinib 400 mg/day. Bone marrow samples were collected before treatment, after 12, 20 and at the end of study treatment (52 weeks) while peripheral blood samples were obtained after 2, 3, 6, 10, 14, 20 and 52 weeks of therapy. The amount of BCR-ABL transcript was expressed as the ratio of BCR-ABL to beta2-microglobulin (beta2M). We show that, following initiation of imatinib, the early BCR-ABL level trends in both bone marrow and peripheral blood samples made it possible to predict the subsequent cytogenetic outcome and response. We propose this method as the method of choice for monitoring patients on imatinib therapy. QRT-PCR studies may be able to identify degrees of molecular response that predict both complete cytogenetic response and long term stability, as well as patterns of response that provide an early indication of relapse and imatinib resistance.
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PMID:Prediction of response to imatinib by prospective quantitation of BCR-ABL transcript in late chronic phase chronic myeloid leukemia patients. 1640 13

Some tumors are dependent on the continued activity of a single oncogene for maintenance of their malignant phenotype. The best-studied example is the Bcr-Abl fusion protein in chronic myelogenous leukemia (CML). Although the clinical success of the Abl kinase inhibitor imatinib against chronic-phase CML emphasizes the importance of developing therapeutic strategies aimed at this target, resistance to imatinib poses a major problem for the ultimate success of CML therapy by this agent. We hypothesized a sequential blockade strategy that is designed to decrease the expression of the Bcr-Abl protein, with the goal of complementing the action of imatinib on kinase activity. In this study, flavopiridol, an inhibitor of transcription, homoharringtonine (HHT), a protein synthesis inhibitor, and imatinib were used singly and in combination against the Bcr-Abl-positive human CML cell line K562. Flavopiridol alone inhibited phosphorylation of the RNA polymerase II COOH-terminal domain, specifically reduced RNA polymerase II-directed mRNA synthesis, and decreased the Bcr-Abl transcript levels. HHT inhibited protein synthesis and reduced the Bcr-Abl protein level. Imatinib directly inhibited the kinase activity of Bcr-Abl. The combinations of flavopiridol and HHT and flavopiridol and imatinib synergistically decreased clonogenicity as evaluated by the median-effect method. Greater synergy was observed when HHT and imatinib were given sequentially compared with simultaneous administration. Imatinib-resistant Ba/F3 cells that were transfected to express the E255K and T315I mutations of Bcr-Abl were not cross-resistant to flavopiridol and HHT. These results provided a rationale for the combination of inhibitors of transcription and/or translation with specific kinase inhibitors.
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PMID:A sequential blockade strategy for the design of combination therapies to overcome oncogene addiction in chronic myelogenous leukemia. 1710 34

A 14-year-old child presented with generalized lymphadenopathy and massive hepatosplenomegaly. Peripheral smear and bone marrow examination were suggestive of Ph' positive chronic myeloid leukemia (CML) in chronic phase. However, lymph node biopsy showed extramedullary blast crisis with evidence of myeloid and T cell markers in blasts. Reverse transcriptase-polymerase chain reaction from lymph node aspirate revealed transcript for bcr-abl p210. Thus, we present here a unique case of childhood CML with extramedullary biphenotypic blast crisis (myeloid/T cell type) at initial presentation with bone marrow remaining in chronic phase. This case provides further evidence to the highly heterogeneous presentation of CML.
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PMID:Biphenotypic extramedullary blast crisis as a presenting manifestation of Philadelphia chromosome-positive CML in a child. 1745 89

We report a case of chronic myelogenous leukemia displaying a variant Philadelphia translocation t(11;22)(q25;q11.2). Breakpoint 11q25 has not previously been reported. Reverse transcriptase polymerase chain reaction and fluorescence in-situ hybridization demonstrated the BCR/ABL rearrangement.
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PMID:[Chronic Myelogenous Leukemia with a Variant Philadelphia Translocation: t(11;22)(q25;q11.2).]. 1815 33

Nested reverse-transcriptase polymerase chain reaction (rt-PCR) was performed on 58 leukemia patients at BIRDEM Laboratory, as a pioneering work in Bangladesh. Thirty of themwere examined for the presence of BCR-ABL being clinically and morphologically diagnosed as chronic myeloid leukemia (CML) and 28 for PML-RARalpha fusion transcripts being clinically and morphologically diagnosed as acute promyelocytic leukemia (APL/ AML M3). The cases were selected for targeted therapy with imatinib mesylate and all-Trans retinoic acid (ATRA) to treat CML and APL respectively. Samples were received either before commencement or during therapy. In the positive cases, amplified DNA products were visible after gel electrophoresis and were reported accordingly. In case of BCR-ABL, positive results were found for five out of six (83.33%) untreated cases and 11 out of 24 (45.83%) treated cases. Positive results for PML-RARalpha were found for 12 out of 14 (85.70%) untreated cases and 11 out of 16 (68.75%) treated cases. A strong positive correlation was found between duration of treatment and negativity of PCR results in both the cases. In present times, the detection of minimal residual disease in patients undergoing treatment for hematological malignancies has become an important goal, not only to monitor the effectiveness of therapy but also to detect an impending relapse. This is the first time in Bangladesh that rt-PCR method is being employed to detect or monitor the presence of abnormal fusion genes in hematological malignancies.
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PMID:Rt-PCR method for diagnosis and follow-up of hematological malignancies: first approach in Bangladesh. 1878 70

This study was purposed to investigate lrp16 gene expression in leukemia cell lines and bone marrow cells of leukemia patients and explore the relationship between lrp16 gene expression and development of leukemia. Reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to test the lrp16 mRNA expression in 4 leukemia cell lines, including K562 (CML), HL-60 (APL), MOLT4 (ALL) and U937 cell lines, as well as in bone marrow-derived cells from 115 patients with leukemia. The effect of lrp16 gene expression on genesis and progression of leukemia was analyzed according to clinicopathological features. The results indicated that positive expression of lrp16 mRNA was found in all 4 leukemia cell lines. For leukemia patients, the positive expression rate of lrp16 mRNA in all AML patients was 38% (16/42), in which the positive rates in AML patients with complete remission (CR) and AML patients without remission were 13% (4/30) and 100% (12/12) respectively. The positive expression rate of lrp16 mRNA in ALL patients was 38% (10/26), in which the positive rate in ALL patients with CR and ALL patients without remission were 16% (3/18) and 87% (7/8) respectively. The positive expression rate of lrp16 mRNA in CML patients was 36% (9/25), in which the positive rates in CML patients with CR and CML patients without remission were 20% (4/20) and 100% (5/5) respectively. The positive rate of lrp16 mRNA in CLL patients was 31% (7/22), in which the positive rate in CLL patients with CR and CLL patients without remission were 11% (2/17) and 100% (5/5) respectively. There was no difference of lrp16 gene expression between leukemia subtypes, but there was statistical significant difference in lrp16 gene expression between CR patients and non CR patients (p < 0.001). It is concluded that the lrp16 gene is a leukemic oncogene and closely relates to genesis and progression of leukemia, which may be an indicator for evaluating clinical efficacy of leukemia therapy.
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PMID:[Lrp16 gene expression in leukemia cell lines and bone marrow cells of leukemia patients and its clinical implication]. 1969 16


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