Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Philadelphia (Ph) chromosome can be detected in the vast majority of patients with chronic myelogenous leukemia (CML). We performed a long-range analysis of chromosomal translocation junction by pulsed-field gel electrophoresis (PFGE) techniques, to examine whether molecular evidence of a reciprocal Ph translocation exists in Ph-positive CML as well as Ph-negative, M-BCR rearrangement-positive CML. The rearrangement within M-BCR and ABL was detected in all patients including nine Ph-positive CML, and three Ph-negative CML. The rearranged 3'-abl fragments showed comigration with rearranged 5'-bcr fragment in rare-cutting restriction enzyme digests in all patients with Ph-positive CML. Thus, the physical linkage of the 3' part of ABL to the 5' side of M-BCR on 22q-chromosome was shown. The same linkage was also demonstrated in all three patients with Ph-negative CML. Meanwhile, the rearranged 3'-bcr fragments showed comigration with rearranged pHabl5' (or T39-1-2) fragments in all patients with Ph-positive CML, indicating the linkage of the 5' end of ABL to the 3' part of M-BCR on 9q+ chromosome. However, this linkage was absent in two Ph-negative CML patients who could be studied. The results suggest that a genomic insertion of 3' ABL into M-BCR in Ph-negative CML occurs by a single cytogenetic event rather than a two-translocation mechanism.
 ...
PMID:Absence in Ph-negative, M-BCR rearrangement-positive chronic myelogenous leukemia of linkage between 5' ABL and 3' M-BCR sequences in Philadelphia translocation. 159 4

The Philadelphia (Ph) translocation is the most common cytogenetic abnormality in adult acute lymphoblastic leukemia (ALL) and is associated with an adverse prognosis. Using polymerase chain reaction (PCR) technology we recently observed a remarkably high incidence (55%) of BCR-ABL rearrangements in adult common ALL patients. In the present study we asked whether a subset of Ph-negative cALL, similarly to Ph-negative chronic myelocytic leukemia (CML) patients, exhibit BCR-ABL transcripts. PCR analysis of 58 adult Ph-negative cALL patients, including 47 cases with a normal karyotype revealed no evidence of chimeric BCR-ABL genes. We conclude that Ph-negative BCR/ABL-positive ALL is very rare entity if existing at all.
 ...
PMID:Polymerase chain reaction analysis of BCR-ABL sequences in adult Philadelphia chromosome-negative acute lymphoblastic leukemia patients. 159 11

The Philadelphia chromosome, originally thought to be associated solely with chronic myelogenous leukemia (CML), has since been identified in acute leukemias and in some cases of lymphoma. The Philadelphia chromosome results from reciprocal translocation of genetic material between chromosome 9 and 22 involving the c-abl and BCR genes respectively. Southern blot analysis of the BCR genes was carried out on biopsy specimens from 49 patients presenting with malignant lymphoma without a previously documented CML phase. In two patients, BCR gene rearrangements were detected in the malignant lymph nodes but not in the bone marrow samples. A third patient showed BCR gene rearrangements in the bone marrow but not in the lymph node. From this limited study, it seems that the overall incidence of BCR gene rearrangement in malignant lymphoma is similar to that observed in adult AML.
 ...
PMID:Rearrangement of BCR genes in malignant lymphoma. 160 94

A 36-year-old woman was referred to our hospital because of splenomegaly in February 1989. The leukocyte count was 55,500/microliter without hiatus leukemicus. The leukocyte alkaline phosphatase score was low (29). The bone marrow showed myeloid hyperplasia (24.8% myeloblasts) but no dysplastic change. The karyotype of the bone marrow cells was 46, XX and a diagnosis of Ph1 (-) CML was made. Treatment with VCR, 6MP and prednisolone made 7-month duration chronic phase, but the abnormal karyotype.[46, XX, i(17q)] gradually increased to 100% of bone marrow cells. The patient died in June 1990. The evidence that not only a BCR rearrangement but also messages of BCR/ABL fusion gene were negative made us able to differentiate this case from Ph1(-), BCR(+) CML. The addition of an i(17q) results in partial monosomy of 17q (17q13;p53 gene) and partial trisomy of 17q (17q11.2-12;G-CSF gene). We examined the rearrangement of p53 gene and G-CSF-dependent tumor cell growth in vitro, demonstrating one allelic loss of p53 gene and independent cell growth on G-CSF respectively. It is thought that in Ph1 (-), BCR (-) CML as well as in Ph1 (+) CML, an i(17q) is related to the progression but not to the initiation of these leukemias. However the precise mechanism, including p53 gene inactivation by point mutation, is still to be elucidated.
 ...
PMID:[i(17q) appearing in acute phase in Ph1-negative, BCR-negative CML]. 163 23

Therapy with interferon-alpha results in complete cytogenetic remission in 15-20% of patients with chronic myelogenous leukemia. Even during prolonged clinical follow-up, most of these patients do not relapse. However, because of the limited sensitivity of cytogenetic techniques (approximately 5%) and Southern blots (approximately 1%), it is uncertain whether the residual malignant clone becomes extinct or persists below the limit of detection in these patients. We used polymerase chain reaction to amplify the chimeric BCR-ABL transcripts in 18 patients with chronic myelogenous leukemia who became Ph1 chromosome negative while receiving treatment with interferon-alpha, either alone or in combination with interferon-gamma. At the time of study, these patients had been Ph1-negative for a median of 22+ months. Fifteen patients were positive for residual BCR-ABL transcripts. No residual BCR-ABL message was detected on analysis of multiple serial samples in three patients. In order to confirm these results, the samples from these three patients, along with positive and negative controls, were analyzed by two independent laboratories in a blinded fashion. In the first laboratory, RNA specimens from all three patients were considered negative using chemiluminescent acidinium-ester-labeled probes. In the second laboratory, samples from all three patients were also negative by conventional polymerase chain reaction (PCR). However, when a second round of amplification was carried out on the amplified samples using a different combination of primers, samples from two of the three patients were positive. The results confirm the presence of a small proportion of BCR-ABL-positive cells in the majority of patients who are in complete remission and highlight some of the potential problems of PCR-based analysis. There is a need to standardize PCR methodology and potential confounding factors need to be addressed before PCR can be generally applied to analysis of minimal residual disease in CML. The implications of BCR-ABL positivity for these patients are discussed.
 ...
PMID:Minimal residual disease in interferon-treated chronic myelogenous leukemia: results and pitfalls of analysis based on polymerase chain reaction. 164 Jul 25

Pulsed field gel electrophoresis was used to construct a long-range map of the normal BCR gene. A single BssHII restriction fragment encompasses all the known exons of the BCR gene (except a small 5' part of exon one). MIuI has one restriction site within the first intron of the BCR gene and another 250 kb downstream. This MIuI fragment contains most of the BCR gene coding sequences apart from the first exon and contains more sequences downstream of the BCR gene than the BssHII fragment. The NarI restriction sites are very close to the BssHII sites in the BCR gene, but they differ in the ABL gene, so that NarI digests could theoretically provide additional information in chronic myeloid leukaemia (CML) patients. This map was used to confirm BCR gene involvement in two CML patients in whom results of conventional Southern blotting of DNA were ambiguous. It was also used in a third patient to demonstrate the presence of a breakpoint apparently outside the BCR gene. Preliminary evidence from the use of PFGE confirms the presence of three BCR-related genes homologous to 3' sequences in the classical BCR gene (BCR-1). These BCR-related genes are located at a considerable distance from BCR-1.
 ...
PMID:Long-range mapping of the normal BCR gene. 164 56

The Philadelphia chromosome defines chronic myeloid leukemia, and is mostly based on a translocation t(9;22) with a typical BCR-ABL rearrangement which also occurs in so called atypical translocations. The transformation of chronic myeloid leukemia is associated with clonal evolution in 80% of cases. The appearance of an isochromosome 17q unequivocally heralds the onset of a myeloid type of blast crisis. Treatment of Ph-positive CML has still to be considered palliative except for allogeneic bone marrow transplantation. The Philadelphia chromosome is also found in about 20% of patients with acute lymphoblastic leukemia and in about 2% of patients with nonlymphoblastic leukemia. It is associated with a poor prognosis. Molecular and cytogenetic findings help differentiating between de novo acute leukemia and blast crisis of chronic myeloid leukemia.
 ...
PMID:[Cytogenetic and clinical features of Philadelphia chromosome positive leukemias]. 170 14

A patient with chronic myelogenous leukemia (CML) associated with pure red cell aplasia (PRCA) is reported. The occurrence of PRCA has been described previously in sporadic cases of Philadelphia chromosome (Ph) positive CML. In this patient, however, the Ph-chromosome was not detected; cytogenetic analysis revealed a t(12;14)(q23;p11) as the sole abnormality. Molecular studies by Southern and PCR analyses showed the rearrangement of the BCR and ABL sequences and expression of the chimeric bcr/abl mRNA, thus confirming the diagnosis of CML. To our knowledge, this is the first report on a case of PRCA associated with Ph negative CML at diagnosis. The possible connection between CML and PRCA is discussed.
 ...
PMID:Pure red cell aplasia in a case of Ph negative BCR/ABL rearranged CML with t(12;14)(q23;p11). 175 63

To determine the role of the BCR-ABL gene in the proliferation of blast cells of patients with chronic myelogenous leukemia, leukemia blast cells were exposed to synthetic 18-mer oligodeoxynucleotides complementary to two identified BCR-ABL junctions. Leukemia colony formation was suppressed, whereas granulocyte-macrophage colony formation from normal marrow progenitors was unaffected. When equal proportions of normal marrow progenitors and blast cells were mixed, exposed to the oligodeoxynucleotides, and assayed for residual colony formation, the majority of residual cells were normal. These findings demonstrate the requirement for a functional BCR-ABL gene in maintaining the leukemic phenotype and the feasibility of gene-targeted selective killing of neoplastic cells.
 ...
PMID:Selective inhibition of leukemia cell proliferation by BCR-ABL antisense oligodeoxynucleotides. 185 87

In four patients, the chromosome 9 breakpoint of the t(9; 22)(q34;q11) had occurred at different sites within an 8.25-kilobase (kb) region situated 5' of ABL exon 1B. Chromosome in situ hybridization and field inversion gel electrophoresis (FIGE) studies showed that ABL exons 1A and 1B were present on the Ph chromosome. Yet this large fusion gene produced an mRNA conventional for chronic myelogenous leukemia (CML). Splicing from BCR exon 3 to ABL exon 2 crossed more than 200 kb and deleted exons 1A and 1B. This breakpoint site may occur in about 10% of all CML patients. Three of our patients have pronounced thrombocytosis, and two had been diagnosed as having Ph-positive essential thrombocythemia. The platelet count of the other patient was not available.
 ...
PMID:Entire ABL gene is joined with 5'-BCR in some patients with Philadelphia-positive leukemia. 186 41


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>