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)

Bone marrow (BM) and peripheral blood cell (PBC) samples of 11 Philadelphia (Ph) chromosome-positive chronic myelogenous leukemia (CML) patients in long-lasting hematologic remission induced by interferon (IFN) treatment were examined for the presence of leukemic hematopoietic precursor cells. Southern blot analysis revealed residual leukemic cells in BM samples of four patients, whereas seven patients showed no aberrant bands. Reverse transcription polymerase chain reaction (RT-PCR), however, amplified bcr-abl-specific cDNA in unfractionated BM or PBC samples in all 11 patients. The patients demonstrating bcr rearrangements in Southern blots had either a mosaic pattern (three patients) of bcr-abl-negative and positive colony-forming precursors (CFU-GEMM, BFU-E, CFU-GM, CFU-Mega), or all colonies were derived from leukemic precursors (one patient). However, in soft agar cultures of four patients without aberrant bands in Southern blots, only colonies without amplifiable bcr-abl transcripts were detectable. In another patient, few bcr-abl-positive colonies were found after 44 months of treatment, but not after 53 and 56 months of therapy. In these patients, therefore, residual disease detectable by PCR analysis of unfractionated cell samples does not appear to reside in the colony-forming cell compartment. The prognostic implications of these observations and the nature of the remaining bcr-abl-positive cells within unfractionated cell samples remain to be determined.
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PMID:Bcr-abl-positive and -negative clonogenic cells in CML patients undergoing long-term interferon treatment. 751 45

Thy-1 (CDw90) is a phosphatidylinositol-anchored cell surface molecule which, when coexpressed with CD34 in normal human bone marrow, identifies a population of immature cells that includes putative hematopoietic stem cells. To date, the characterization of Thy-1 expression has been confined largely to normal tissues and cell lines. In this study, we evaluated the frequency and intensity of Thy-1 expression as defined by reactivity with the anti-Thy-1 antibody 5E10 in 38 cases of CD34+ acute leukemia (21 acute myelogenous leukemia [AML], 8 chronic myelogenous leukemia [CML] in blast crisis, and 9 acute lymphoblastic leukemia [ALL]). In 34 of 38 cases (89%) the CD34+ cells lacked expression of the Thy-1 antigen. High-density Thy-1 expression was found in 1 case of CML in lymphoid blast crisis, and low-density Thy-1 expression was identified on a portion of the leukemic cells in 2 cases of AML with myelodysplastic features, and 1 case of CML in myeloid blast crisis, suggesting a possible correlation between Thy-1 expression and certain instances of stem cell disorders such as CML and AML with dysplastic features. In contrast, the dissociation of Thy-1 and CD34 expression in the majority of acute leukemias studied suggests that the development of these leukemias occurs at a later stage than the hematopoietic stem cell. Characterization of Thy-1 expression in acute leukemia may eventually provide insights into the origin of the disease. In addition, separation of leukemic blasts from normal stem cells based on Thy-1 expression may prove useful in assessing residual disease, as well as in excluding leukemic blasts from stem cell preparations destined for autologous bone marrow or peripheral stem cell transplantation.
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PMID:Characterization of Thy-1 (CDw90) expression in CD34+ acute leukemia. 754 Aug 89

A substantial minority of patients with chronic myeloid leukaemia (CML) achieve a complete response to treatment with interferon-alpha (IFN-alpha), defined as the disappearance of Philadelphia chromosome positive metaphases or, for patients who are Philadelphia chromosome negative but BCR-ABL positive, the disappearance of the leukaemic clone as assayed by Southern blot. We have measured the levels of BCR-ABL transcripts in 20 such patients by quantitative PCR. Results were standardized for both quality and quantity of cDNA by quantification of ABL as an internal control. All 20 patients had evidence of residual disease; the median number of transcripts was 750/micrograms RNA (range 10-22,000) and the median BCR-ABL/ABL ratio was 0.17% (range 0.0008-3.6%). Our findings show that CML has not been eradicated in any patient and that the quantity of residual disease in complete responders may vary by as much as four orders of magnitude.
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PMID:Variable numbers of BCR-ABL transcripts persist in CML patients who achieve complete cytogenetic remission with interferon-alpha. 860 27

The very rapid development of techniques based on use of the polymerase chain reaction (PCR) for characterizing molecular lesions in leukaemia and lymphoma mow offers the opportunity for monitoring residual disease at a sensitivity of one malignant cell in 10(5) or 10(6) normal cells. Maximal specificity is achieved when the DNA sequences amplified are truly leukaemia-specific (i.e. BCR/ABL in CML, PML/RAR-alfa in APL, AML1/ETO in t(8; 21) AML and CBFB/MYH1 in inv(16) AML). A good level of sensitivity may also be achieved by using immunoglobin heavy chain (IGH) and T-cell receptor (TCR) gene rearrangements if a clonospecific probe can be generated. For clinical purposes the crucial issues are the following: can PCR techniques be used for confirmation of diagnosis and evaluation of extent of disease? Can PCR data obtained be developed to quantitate the PCR product and thereby increase its predictive value? These and other issues are still a matter of debate and several studies are presently in progress to address these points.
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PMID:Minimal residual disease detection in human leukemias: biologic and clinical significance. 765 31

Polymerase chain reaction (PCR) technology has been useful in clarifying molecular or minimal residual disease (MRD) status in patients with leukemia. Although PCR has several inherent problems, accumulated data have demonstrated that patients with leukemia harbor PCR-detectable residual disease for a certain period despite clinical remission. This has been for approximately 1 year in childhood acute lymphoblastic leukemia and adult acute promyelocytic leukemia after chemotherapy and for approximately 2 years in chronic myelogenous leukemia after bone marrow transplantation. Ultimately, PCR-undectable residual disease is necessary for achieving cures in most patients. However, it is difficult to make an early prediction of subsequent relapse after obtaining PCR negatively, since the emergence of PCR-detectable disease occurs only several months before clinical relapse. Therefore, PCR negativity is necessary but not sufficient for achieving cures in most patients with leukemia. Periods of persistent PCR-detectable disease will require further investigations for relapse prediction. More accurate serial quantitation would clarify a precise MRD status in leukemia patients and might allow for more accurate prediction of relapse. Since PCR-undectable residual disease is necessary for cures in most patients, it can be proposed that a "molecular remission", defined as PCR-undetectable disease, is a milestone and target for achieving cure by cytoreductive therapy.
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PMID:Clinical significance of minimal residual disease in leukemia detected by polymerase chain reaction: is molecular remission a milestone for achieving a cure? 769 32

The purpose of this report was to evaluate scintigraphy analysis of Southern blot hybridization as a method to quantify the breakpoint cluster region (BCR) rearrangement of Philadelphia chromosome (Ph)+ chronic myelogenous leukemia (CML). Cytogenetic and molecular studies performed simultaneously on 474 bone marrow and/or blood samples from 300 patients treated with alpha-interferon-based therapy were compared. Molecular results were expressed as the percentage of rearranged BCR bands versus the total scintigraphic signal. The percentage of Ph+ metaphases was calculated on 25 metaphases. The results of molecular studies obtained on both peripheral blood and bone marrow samples were identical. The rank correlation between the BCR quantification and the percentage of Ph positivity in 465 samples was excellent (r = .78). However, of 99 samples with a normal karyotype, 24% had a BCR rearrangement. Of 86 samples with no BCR rearrangement, 13% showed a Ph chromosome. Of 49 samples with partial cytogenetic remission (Ph+ metaphases, 1% to 34%), 23% had no BCR rearrangement. In samples with a minor or no cytogenetic response (Ph+ metaphases, > 34%), BCR analysis overestimated the degree of response in 73 of 326 samples (22%). Nevertheless, survival analysis by BCR quantification level showed statistically better outcome for patients in complete or partial molecular response (P < .01). Molecular quantification of BCR was useful in monitoring the course of Ph+ CML. This method, which can be used on peripheral blood, detected residual disease not shown by cytogenetic analysis and was prognostically relevant as a measure of disease suppression.
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PMID:Quantification of the breakpoint cluster region rearrangement for clinical monitoring in Philadelphia chromosome-positive chronic myeloid leukemia. 774 30

The Philadelphia chromosome (Ph) is the cytogenetic hallmark of chronic myeloid leukaemia (CML) and is used to confirm the diagnosis of CML based on clinical and morphological criteria. We investigated 14 patients with features of CML but without detectable Ph chromosome. In seven patients, referred to as BCR+, M-bcr/abl rearrangement was detected by polymerase chain reaction (PCR). The seven remaining patients did not have M-bcr/abl rearrangement and are described as BCR-. BCR- patients were younger, had lower white blood cell counts (WBC) and lower basophilia. Four BCR- and four BCR+ patients underwent blastic transformation (BT). Response to therapy was fairly similar in both populations. According to French-American-British (FAB) Cooperative Leukaemia Group guidelines, all BCR- patients were classified as having classic form CML or 'chronic granulocytic leukaemia' (CGL) when based only on morphological data. This study further confirms the existence of true CML cases without Ph chromosome or M-bcr/abl rearrangement and shows that this entity differs only slightly from classic form Ph+ CML. The Ph-BCR- subgroup raises two problems. First, the differential diagnosis with atypical CML or CMML, based on morphological data, and secondly, the therapeutic follow-up in the absence of a specific marker. In contrast, the residual disease of Ph-BCR- patients can be monitored by PCR. More advanced molecular and biochemical techniques will be required to understand which molecular mechanisms underlie Ph-BCR- CML, resulting in phenotypes sometimes indistinguishable from Ph+ CML.
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PMID:Philadelphia chromosome-negative chronic myeloid leukaemia: a report of 14 new cases. 779 55

By using "nested" retrotranscriptase/polymerase chain reaction (RT/PCR) technique, we determined the expression patterns of the BCR-ABL fusion gene resulting from the chromosomal translocation t (9; 22) in leukemias with Ph1 chromosome. Three distinct isoforms of fusion gene transcripts were discovered: ela2, b2a2 and b3a2. In 10 cases of chronic myelogenous leukemia (CML), only two types (b2a2 and b3a2) were observed. However, in 8 cases of Ph1 chromosome positive acute lymphoblastic leukemia (Ph1 + ALL), all three types were detected, including two cases characterized by the coexistence of ela2 and b2a2 or b3a2 types. Moreover, the RT/PCR procedure established in the present study proved to be a very sensitive method, allowing the detection of one leukemic cell among 10(5)-10(6) normal cells. Thus, a positive RT/PCR result was obtained in two Ph1 + ALL cases just after chemotherapy-induced clinical remission (CR), suggesting the presence of residual disease. One case remained RT/PCR positive four months after achieving CR and relapsed in the fifth month, while the other case converted to RT/PCR negative eight months later and is now in CR for 18 months. Therefore the detection of BCR-ABL fusion gene is of importance not only in the study of the pathogenesis of Ph1 + leukemias but also in their diagnosis and monitoring of minimal residual disease during CR.
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PMID:[Detection on BCR-ABL fusion gene in Ph1 chromosome positive leukemia by "nested" retrotranscriptase/polymerase chain reaction]. 786 99

Between March 1983 and December 1992, we performed 178 allogeneic BMTs for patients with hematopoietic stem cell disorders: 48 acute myelogenous leukemia (AML), 27 acute lymphoblastic leukemia (ALL), 40 chronic myelogenous leukemia (CML), 55 severe aplastic anemia (SAA), 6 myelodysplastic syndrome (MDS), 1 non-Hodgkin's lymphoma and 1 hybrid leukemia. Twenty-five of 48 AML are in disease-free survival (DFS). Fifteen of 27 ALL are in unmaintained remission. Twenty-four of 40 CML are in DFS. Forty-four out of 55 SAA patients are alive and well. Comparing the survival between standard (< or = CR1: 21 of 31 (68%)) and high risk (> or = CR2: 4 of 17 (24%)) AML, our data suggest that the preparative regimen for high risk AML was not potent enough to eradicate the residual disease in advanced AML. Although our cases are limited and the follow-up period is short, the result of ALL (overall: 56%, standard risk (adult < or = CR1, children < or = CR2: 10 of 14 (71%) and high risk (adult > or = CR2, children > CR2): 5 of 13 (38%)) and CML (overall: 60%; CP: 19 of 27 (70%), AP or BC: 5 of 13 (38%)) are promising. The probability of 5 year survival of SAA was 80 +/- 4 years.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Allogeneic bone marrow transplantation in Korea: 1983-92. 792 Mar 1

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


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