Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three new cases are reported of cytogenetically Philadelphia-negative (Ph-) chronic myelocytic leukemia (CML), with positive BCR/ABL gene rearrangement according to a reverse transcriptase polymerase chain reaction technique. Fluorescence in situ hybridization (FISH) studies using different probes showed three different situations involving chromosomes 9 and 22 for the masked BCR/ABL fusion gene. With the use of BCR/ABL-extra signal and CEP 9 probes (Vysis, Downers Grove, IL, USA), FISH studies detected the BCR/ABL fusion gene at the end of chromosome 9 in patient 1, a BCR/ABL fusion gene on both chromosomes 22 in patient 2 (who was in an accelerated phase of CML), and a BCR/ABL fusion signal on chromosome 22 in patient 3. Interestingly, FISH interphase signals showed the same pattern in patients 1 and 3, but the BCR/ABL fusion gene was located on different chromosomes. Careful interpretation of the results and a simultaneous study of nuclei and metaphases are therefore recommended in each case. In conclusion, in cases of Ph- CML, FISH studies are of paramount importance since they can detect chromosomal reorganization and its location, and can also provide quantitative follow-up of these patients.
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PMID:Chimeric BCR/ABL gene detected by fluorescence in situ hybridization in three new cases of Philadelphia chromosome-negative chronic myelocytic leukemia. 1260 28

The BCR/ABL gene rearrangement is the causing factor in chronic myeloid leukemia (CML). In most cases, it is cytogenetically visualized as a translocation between chromosomes 9 and 22, known as the Philadelphia (Ph) translocation. About 5-10% of CML patients lack cytogenetic evidence of the Ph translocation but show BCR/ABL fusion by fluorescence in situ hybridization (FISH) or reverse transcriptase-polymerase chain reaction. Deletions around the breakpoints on the derivative 9 including ABL and or BCR sequences occur in 10-15% of Ph+ CML patients and are thought to have prognostic significance. We describe two patients with CML and normal karyotype in whom cryptic rearrangements involving chromosomes 9 and 22 resulted in the causative BCR/ABL gene. FISH with a three-color probe combination revealed BCR/ABL fusion on chromosome 9 without deletion in one patient; the other patient had BCR/ABL on chromosome 22 with an associated derivative 9 deletion. We discuss the proposed mechanisms in the formation of BCR/ABL in the setting of a normal karyotype. Some authors reported that patients with the chimeric gene located on the derivative 9 have a poor clinical course. We suggest that deletion rather than location of the chimeric gene alone is more likely to be associated with prognosis.
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PMID:BCR/ABL rearrangement in two cases of Philadelphia chromosome negative chronic myeloid leukemia: deletion on the derivative chromosome 9 may or not be present. 1633 61

The virtually obligatory presence of the Philadelphia chromosome may suggest a causal homogeneity, but chronic myelogenous leukemia (CML) is a clinically heterogeneous disease. This may be a consequence of the variable BCR breakpoints on chromosome 22 and of nonrandom secondary chromosomal abnormalities. We present the case of a boy, age 12, investigated in blastic phase of CML. Karyotyping with conventional and multiplex fluorescence in situ hybridization (FISH and M-FISH) karyotyping, complemented with reverse transcriptase-polymerase chain reaction, identified a variant Philadelphia translocation t(9;14;22)(q34;q32;q11) involving a cryptic BCR/ABL fusion with formation of the p190(Bcr-Abl) oncoprotein. M-FISH revealed also an unbalanced jumping translocation of 17q11 approximately qter alternatively present on chromosomes 14 or 20, apparently hithertofore unreported in hematological malignancies. Another secondary aberration, dup(3)(q25q28), was revealed by multipoint interphase FISH (mpI-FISH). Gain of this region is known in adult hematological malignancies and solid tumors, suggesting its general involvement in tumor initiation or progression (or both), regardless of tissue origin.
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PMID:Jumping translocation of 17q11 approximately qter and 3q25 approximately q28 duplication in a variant Philadelphia t(9;14;22)(q34;q32;q11) in a childhood chronic myelogenous leukemia. 1636 67

Expression of the CDH13 gene in chronic myeloid leukaemia (CML) patients at different clinical stages, and its relationship with the BCR/ABL fusion gene, is investigated. Expression of the CDH13 gene and the BCR/ABL fuse gene is investigated in peripheral blood from 30 healthy adults, 25 primary CML patients and 25 CML patients in blast crisis using the EvaGreen real-time reverse transcriptase polymerase chain reaction (RT-PCR). Results showed that BCR/ABL fusion gene expression in the blast crisis CML patients was 4.72-fold higher than that in patients with primary CML. Expression of CDH13 mRNA in primary and blast crisis CML patients was lower than in the healthy adults, reduced 64% and 75%, respectively. Expression of CDH13 showed a negative correlation with the BCR/ABL fusion gene. The data indicate that the decline of CDH13 expression accompanied the different clinical stages of CML and probably was involved in over-expression of the BCR/ABL fusion gene.
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PMID:Cadherin-13 in primary and blast crisis chronic myeloid leukaemia: declining expression and negative correlation with the BCR/ABL fusion gene. 1934 22


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