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)

Forty-eight long-term disease-free chronic myelogenous leukemia (CML) patients, who had received unmanipulated allogeneic bone marrow transplants (BMT) for eradication of the Philadelphia (Ph1)-positive clone were studied by polymerase chain reaction (PCR), using a very sensitive PCR procedure and very stringent criteria for preventing and revealing contamination. Nine patients (18%) were positive at the first PCR examination, but only one patient remained PCR positive four years after. However, a second PCR analysis performed on new bone marrow samples obtained at a median interval of 14 months (range 6-16) after the first specimen collection from six of nine originally positive cases, and from 16 of 39 originally negative cases, showed that only one of the six positive cases remained positive, whereas negativity was confirmed in all the originally negative patients. These data are evidence that the Ph1-positive clone is apparently completely eradicated in the majority of CML patients who survive disease-free long-term after an unmanipulated allogeneic BMT and that only sporadic cases remain PCR-positive four years post-BMT. The data also show that at least two sequential bone marrow samples for each patient must be analyzed before drawing conclusions regarding the stable persistence of BCR/ABL transcripts and the minimal residual disease status.
Leukemia 1992 Jun
PMID:Minimal residual disease status in transplanted chronic myelogenous leukemia patients: low incidence of polymerase chain reaction positive cases among 48 long disease-free subjects who received unmanipulated allogeneic bone marrow transplants. 160 89

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.
Leukemia 1992 Jun
PMID:Rearrangement of BCR genes in malignant lymphoma. 160 94

Fifteen chronic myelocytic leukemia patients in durable complete cytogenetic conversion (CCC) under interferon therapy, were monitored every three to six months by bone marrow (BM) karyotypes and/or reverse-transcription polymerase chain reaction (RT-PCR) on peripheral blood (PB) leukocytes (by a nested primer approach using two rounds of amplification, 30 cycles each). Special care was taken to minimize the risk of contamination. The median time of follow-up after first CCC was 12 months (range, 6-30). Thirty five BM karyotypes were performed. Only three patients demonstrated the transient reappearance of a few Philadelphia-positive metaphases, while other patients remained in CCC. Forty five PB samples were studied by RT-PCR. In two patients, no BCR/ABL transcript could be detected in three consecutive samples. In the 13 other cases, RT-PCR was intermittently negative, indicating a level of residual leukemic cells close to the threshold of sensitivity of the technique.
Leukemia 1992 Jun
PMID:Complete cytogenetic conversion in chronic myelocytic leukemia patients undergoing interferon alpha therapy: follow-up with reverse polymerase chain reaction. 160 97

Recent developments in CML research are illustrated by the results of one large randomized multicenter study carried out by the German CML Study Group. From July 1983 to January 1991, a total of 703 CML patients were recruited; 624 patients were randomized to compare hydroxyurea and interferon alpha (IFN) with busulfan. The median survival of Ph+ patients by now is 3.95 years, that of Ph- patients 1.1 years. Some difference in survival is recognizable between the treatment arms, but this is not yet significant. Fewer adverse effects are being observed in the hydroxyurea group. Ph-negative patients tend to have lower white blood cell and platelet counts. Patients (164) were randomized to receive IFN. In 50 patients (30%) IFN had to be terminated because of adverse effects, therapy resistance, or other reasons. Reduction of the Ph-chromosome was observed in 20% of evaluable patients. In 3 patients complete cytogenetic remissions were observed. Clinically relevant neutralizing antibodies were detected in 9 cases. Prospectively evaluated age, organomegaly related symptoms, Karnofsky index, extramedullary manifestations, erythroblasts, and percent of circulating blasts proved to be of prognostic significance. A prognostic score (score 1) was determined and compared to Sokal's score. It is expected that the study results will allow statements as to the advantages or disadvantages of the use of busulfan, hydroxyurea and IFN in the treatment of CML as well as to the reliability of prognostic markers.
Leukemia 1992
PMID:Chronic myelogenous leukemia: recent developments in prognostic evaluation and chemotherapy. The German CML Study Group. 160 5

The breakpoints in chromosome 22 were determined in five children with Philadelphia-positive chronic myeloid leukemia. All had rearrangements within the major breakpoint cluster region (M-bcr). Four patients had breakpoints in the 5' region of M-bcr (zones 1-3), whereas one had a rearrangement in the 3' region (zone 4). The patient with the 3' rearrangement was the only one to develop a lymphoid blast crisis; he also had a substantially longer survival (102 months) than the others (11-54 months).
Leukemia 1992 Jul
PMID:Molecular analysis of Philadelphia-positive childhood chronic myeloid leukemia. 162 93

We have used the MTT colorimetric assay to determine the sensitivity to ethacrynic acid of lymphocytes from normal donors and of peripheral blood cells from leukaemia patients. Whereas normal lymphocytes and cells from acute or chronic myeloid leukaemia showed similar sensitivities (median inhibitory dose, ID50 = 20-22 microM), lymphocytes from chronic lymphocytic leukaemia patients were much more sensitive (ID50 = 6 microM). This result was found irrespective of the assay duration.
Leukemia 1992 Jul
PMID:Selective toxicity of ethacrynic acid towards lymphocytes of chronic lymphocytic leukemia in vitro. 162 94

Therapy with alpha-interferon (IFN alpha) can suppress the Ph1-positive hemopoiesis in a percentage of patients with chronic myelogenous leukemia (CML). We used IFN alpha to treat a 30-year-old CML patient, characterized by favourable prognostic signs (such as low leukocytosis, absence of splenomegaly and no increase in bone marrow blasts) at diagnosis, and obtained a complete remission, as evaluated by Southern blot and cytogenetic analysis, after one year of treatment. However, the polymerase chain reaction (PCR) revealed the persistence of a minimal residual disease. The IFN alpha therapy was stopped and the hematological status remained stable until eighteen months later, when a cytogenetic analysis revealed the appearance of a clone characterized by t(9;22) and trisomy 8, accounting for 30% of bone marrow metaphases. This cell population spontaneously regressed in the following months, before any cytotoxic treatment. However, as leukemic cells, detected by PCR, were still present, the patient received a high dose chemotherapy, which induced the complete eradication of the Ph1-positive clone, as demonstrated by the absence of bcr-abl transcript at the PCR reaction. Molecular and cytogenetic remission persist one year later, without any further therapy.
Leukemia 1992 Jul
PMID:Transient cytogenetic relapse in a Ph1-positive chronic myelogenous leukemia patient previously treated with alpha-interferon. 162 97

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.
Leukemia 1992 Aug
PMID:Minimal residual disease in interferon-treated chronic myelogenous leukemia: results and pitfalls of analysis based on polymerase chain reaction. 164 Jul 25

Four human chronic myeloid leukemia (CML) cell lines, BV173, K562, KCL-22, and KYO-1, were studied for inactivation of human tumor suppressor gene p53. Southern blotting showed allele deletion in KCL-22 and cytogenetic studies showed a chromosome 17 deletion in KYO-1 but no gross structural abnormalities in the other two lines. Northern blotting showed increased amounts of normal size p53 mRNA in BV-173 and KYO-1, trace amounts in KCL-22, and none in K562. Direct sequencing of p53 cDNA revealed a missense point mutation in KYO-1 and a single base pair deletion consistent with a coding frame shift in KCL-22. Both abnormalities in these myeloid cell lines were located in the highly conserved region of p53. Studies with two monoclonal antibodies showed that the three cell lines with p53 mRNA had readily detectable p53 proteins. In KYO-1 and BV173 cells the p53 protein was located mainly in the nuclei but KCL-22 cells had weak staining in the cytoplasm. Our data support the assumption that inactivation of p53 tumor suppressor function in myeloid blast transformation of CML may result from point mutations or deletions that produce mutant proteins.
Leukemia 1992 Aug
PMID:p53 in chronic myeloid leukemia cell lines. 164 Jul 38

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.
Leukemia 1991 Jul
PMID:Long-range mapping of the normal BCR gene. 164 56


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