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)

The elucidation of the molecular biology of chronic myeloid leukemia (CML) has provided a paradigm for understanding leukemogenesis, targeted drug development, and disease monitoring at the molecular level. Minimal residual disease (MRD) monitoring by fluorescence in situ hybridization and polymerase chain reaction (PCR) has become an important tool in predicting relapse after allogeneic transplant, allowing for early intervention strategies such as donor lymphocyte infusion. MRD monitoring is important for assessment of disease status in patients who obtain a complete cytogenetic remission, and this approach is likely to play an important role in following patients to determine who will relapse on imatinib mesylate therapy. This review focuses primarily on MRD monitoring by PCR.
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PMID:Monitoring bcr-abl by polymerase chain reaction in the treatment of chronic myeloid leukemia. 1289 96

In order to investigate the features of M-bcr/abl and m-bcr/abl fusion transcripts in patients with chronic myeloid leukemia (CML) after allogeneic stem cell transplantation (SCT), M-bcr/abl and m-bcr/abl fusion transcripts were sequentially detected by RT-PCR technique in 72 CML patients after SCT. The results showed that M-bcr/abl positive rate (79.2%, 42/53) within 6 months after SCT was remarkably higher than that in 6-12 months group (34.3%, 11/32) and >or= 12 months group (35.1%, 13/37) (P < 0.001), and the clinical relapse rates in corresponding periods were 1.9% (1/53), 0% (0/32) and 16.2% (6/37) respectively. M-bcr/abl and m-bcr/abl fusion transcripts occurred in 5 of 6 clinically relapsed patients. In period of more than 6 months after transplantation, none of 17 M-bcr/abl(+) samples from 14 patients in cytogenetic remission appeared positive reaction of m-bcr/abl. It is concluded that M-bcr/abl(+) fusion transcript still existed in most patients after SCT, and usually disappeared within 6 months. Existence of M-bcr/abl is not a clinical relapse marker in CML patients. Simultaneous detection of M-bcr/abl and m-bcr/abl fusion transcripts can be helpful for monitoring residual disease.
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PMID:[Follow-up detection of M-bcr/abl and m-bcr/abl fusion transcripts in chronic myeloid leukemia patients after allogeneic hematopoietic stem cell transplantation]. 1296 64

A significant proportion of chronic myeloid leukemia (CML) patients achieve a major cytogenetic remission (MCR) to imatinib therapy after failing interferon (IFN) alpha-based protocols. We sought to determine levels of residual disease in patients with MCR using various molecular methods and to establish a relation between residual BCR-ABL transcript levels and rate of relapse in complete cytogenetic remission (CCR). Response was measured by conventional cytogenetic analysis, hypermetaphase and interphase fluorescence in situ hybridization (HM-FISH, IP-FISH) of bone marrow (BM) cells, qualitative nested and quantitative reverse transcriptase polymerase chain reaction (RT-PCR) for BCR-ABL transcripts. We investigated 323 peripheral blood (PB) and BM samples from 48 CML patients who achieved a complete (Ph+ 0%; n=41) or partial (Ph+ 1-34%; n=7) cytogenetic remission after 3-20 months of imatinib therapy. Prior to imatinib, 35 patients were in chronic phase (CP), eight in accelerated phase (AP), four in myeloid and one in lymphoid blast crisis. HM-FISH results correlated with ratios BCR-ABL/ABL in PB and BM. In patients with CCR, residual disease was detectable by HM-FISH (31%), IP-FISH (18%), and RT-PCR (100%). During follow-up, BCR-ABL became undetectable in two patients (one CP, one AP) by both nested and quantitative RT-PCR. CCR is ongoing in 30 evaluable patients, 11 patients have relapsed. At the time of best response, median ratios BCR-ABL/ABL were 2.1% (range 0.82-7.8) in patients with subsequent relapse and 0.075% (range 0-3.9) in patients with ongoing remission (P=0.0011). All 16 CP patients, who achieved ratios BCR-ABL/ABL <0.1% as best molecular response are in continuous remission, while 6/13 patients (46%) with ratios >/=0.1% have relapsed (P=0.0036). We conclude that: (i) in patients with CCR to imatinib, HM-FISH and RT-PCR usually reveal residual BCR-ABL+ cells; (ii) RT-PCR results derived from PB and BM are comparable in CP CML; and (iii) low levels of residual disease with ratios BCR-ABL/ABL &<0.1% are associated with continuous remission.
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PMID:Molecular monitoring of response to imatinib (Glivec) in CML patients pretreated with interferon alpha. Low levels of residual disease are associated with continuous remission. 1297 Jul 65

We sought to determine dynamics of BCR-ABL mRNA expression levels in 139 patients with chronic myelogenous leukemia (CML) in early chronic phase, randomized to receive imatinib (n=69) or interferon (IFN)/Ara-C (n=70). The response was sequentially monitored by cytogenetics from bone marrow metaphases (n=803) and qualitative and quantitative RT-PCR from peripheral blood samples (n=1117). Complete cytogenetic response (CCR) was achieved in 60 (imatinib, 87%) vs 10 patients (IFN/Ara-C, 14%) after a median observation time of 24 months. Within the first year after CCR, best median ratio BCR-ABL/ABL was 0.087%, (imatinib, n=48) vs 0.27% (IFN/Ara-C, n=9, P=0.025). BCR-ABL was undetectable in 25 cases by real-time PCR, but in only four patients by nested PCR. Median best response in patients with relapse after CCR was 0.24% (n=3) as compared to 0.029% in patients with continuous remission (n=52, P=0.029). We conclude that (i) treatment with imatinib in newly diagnosed CML patients is associated with a rapid decrease of BCR-ABL transcript levels; (ii) nested PCR may reveal residual BCR-ABL transcripts in samples that are negative by real-time PCR; (iii) BCR-ABL transcript levels parallel cytogenetic response, and (iv) imatinib is superior to IFN/Ara-C in terms of the speed and degree of molecular responses, but residual disease is rarely eliminated.
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PMID:Dynamics of BCR-ABL mRNA expression in first-line therapy of chronic myelogenous leukemia patients with imatinib or interferon alpha/ara-C. 1452 62

Here, we describe a patient diagnosed with chronic myelogenous leukemia who relapsed after matched unrelated donor SCT. The patient was treated with imatinib mesylate and donor lymphocyte infusions, and achieved a complete molecular remission. Additionally, safety and efficacy of imatinib mesylate in a total of 134 patients from 8 centers who underwent allogeneic or syngeneic stem cell transplantation (SCT) and had a relapse of Philadelphia chromosome positive leukemia was reviewed. Data was compiled from abstracts accepted as oral or poster presentations at the ASH (American Society of Hematology) 2001 and EBMT (European Group for Blood and Marrow Transplantation) 2001 & 2002 meetings and additionally literature published on this patient group. Efficacy of imatinib therapy was assessed by morphology, cytogenetic analysis, and determination of donor chimerism. In the evaluable population, hematologic and cytogenetic responses were observed in 66% and 60% of the patients, respectively. Fifty-one of 114 (45%) patients achieved a complete cytogenetic response. No response or progress of disease was noted in 22 out of evaluable 91 patients. The observation period was limited to a maximum of 28 months. A significant improvement in donor chimerism was frequently observed. Only five cases of significant GVHD were reported. Preliminary results show that imatinib mesylate has the potential to positively influence the ratio of donor and recipient cells without inducing a high incidence of severe GVHD. The data suggest that earlier start of imatinib mesylate prior to hematologic relapse in minimum residual disease (MRD) positive patients is a promising treatment concept.
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PMID:Current results on the use of imatinib mesylate in patients with relapsed Philadelphia chromosome positive leukemia after allogeneic or syngeneic hematopoietic stem cell transplantation. 1452 51

Long-term follow-up of peripheral cellular chimerism in patients treated with BMT or PBSCT revealed the usefulness of their continuous monitoring at molecular level. Our results are based on monitoring of 120 patients, who were followed for at least 24 months. Comparison of the patients treated for chronic myelogenous leukemia (CML), acute myelocytic leukemia (AML), acute lymphocytic leukemia (ALL), myelodysplastic syndromes (MDS) and aplastic anaemia (AA) revealed that mixed chimerism was practically absent in MDS and relatively long-lasting in ALL and AA (regardless to substantially different post-transplantation treatment). The first disease relapses signalized by molecular checking of mixed peripheral chimerism were observed also after a period of remission lasting for several years. Molecular watching enables us to detect relapses at their very beginning that would remain hidden to less sensitive methods. We believe that all of the transplanted patients ought to be monitored for residual disease i.e. cellular chimerism using molecular methods without time limits. On the other hand low level of mixed cellular chimerism is not necessarily a sign of disease progression and can remain unchanged as "status quo" for a very long period.
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PMID:Long-term follow-up of chimerical state of the patients transplanted for different haematologic diseases. 1457 30

Imatinib Mesylate, a specific inhibitor of BCR/ABL tyrosine kinase, was developed as a molecularly targeted drug for the treatment of patients with chronic myelogenous leukemia. We evaluated effectiveness of the drug on cytogenetic response for monitoring residual disease using fluorescence in situ hybridization(FISH), reverse transcription-nested-polymerase chain reaction(RT-nested-PCR) and competitive PCR strategy. Of 9 patients in chronic phase, 7 achieved major cytogenetic response(CR) and 2 achieved minor CR by FISH. In 3 out of 6 patients with complete CR, no BCR/ABL gene was detected by RT-nested-PCR in peripheral blood or bone marrow specimens. Of 4 patients in accelerated phase, 1 achieved complete CR but 3 developed blast crisis. Despite high efficacy of Imatinib, 5 out of 13 patients showed resistance to the drug. To clarify the mechanism of resistance, we have newly developed a method for investigating a point mutation of T315I in tyrosine kinase domain of BCR/ABL gene using RT-PCR restriction digested analysis. None of them showed T315I mutation. The sensitivity of the method was as low as 10 copies of mutant gene. The method is useful for screening the mutation when there are many clinical samples or low copy number of BCR/ABL gene. BCR/ABL value obtained by FISH was of use to predict cytogenetic response when residual disease was above 2 to 3%. Below this level, the routine use of RT-nested-PCR was suffices to monitor minimal residual disease.
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PMID:[The monitoring of residual disease for chronic myelogenous leukemia patients treated with imatinib mesylate: detection of T315I mutation in ATP binding site of BCR/ABL gene]. 1465 3

Residual disease in chronic myeloid leukemia patients may be assessed by various molecular methods. After imatinib treatment a significant proportion of patients achieve complete cytogenetic remission (CCR) and a sensitive method is necessary to monitor treatment response and to detect early signs of relapse. Reverse-transcriptase polymerase chain reaction (RT-PCR) is by far the most sensitive approach to assess residual disease in this group of patients. Qualitative PCR methods give only limited information about the residual leukemic mass. Quantitative RT-PCR (Q-PCR) assays enable to monitor the kinetics of residual BCR-ABL transcripts over time in patients with a good response to imatinib. Early Q-PCR results on imatinib treatment can help to identify individuals who are likely to have a good response. In chronic phase patients after CCR, Q-PCR may identify patients who are likely to continue with their CCR or to relapse and may help to optimize treatment for this group of patients. The definition of molecular surrogate endpoints beyond CCR for studies which are currently planned demands standardization of the nomenclature and of technologies to measure these targets.
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PMID:Molecular surveillance of chronic myeloid leukemia patients in the imatinib era - evaluation of response and resistance. 1517 8

Detection and monitoring of minimal residual disease has become one of the most prevalent topics in chronic myeloid leukemia(CML) therapy. The goal of early detection of residual disease is to allow timely therapeutic intervention before overt relapse of therapy resistant disease occurs. The most powerful tool to serve this purpose is polymerase chain reaction (PCR). Major improvements in assay techniques have advanced PCR from a purely qualitative test with considerable variability of test results to a real-time quantitative assay with far more reproducible results than were possible before. At the same time, treatment of CML has changed dramatically since the introduction of imatinib. Integration of therapy and molecular assays such as PCR, in addition to a profound understanding of the pathophysiology of CML, has assumed even more importance. Quantitative PCR testing has become the standard monitoring strategy for patients undergoing stem cell transplantation. Although correlations have been established between positive test results and probability of relapse, no absolute guidelines for monitoring exist, especially for patients treated with imatinib.
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PMID:Monitoring of minimal residual disease in chronic myeloid leukemia. 1527 98

Experimental and clinical evidence for persistence of polyclonal Philadelphia chromosome negative (Ph-) progenitors in chronic myelogenous leukemia (CML) patients has provided the rationale for autologous transplantation. Clinical trials of autologous transplantation suggest that this procedure can induce cytogenetic remissions in a subset of patients and may be associated with longer-than-expected patient survival. Most autologous transplant recipients, however, continue to have evidence of persistent leukemia. Recent reports indicating that it is possible to collect sufficient numbers of Ph- peripheral blood stem cells for autologous transplantation from most patients in complete cytogenetic remission on imatinib treatment have rekindled interest in autologous transplantation in CML. Additional approaches to eliminate residual disease in autografts and to sustain cytogenetic response after transplantation, however, will be required to achieve long-term restoration of Ph- hematopoiesis. Several promising methods to improve purging of the autograft and for more effective elimination of residual leukemia are being explored.
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PMID:Autologous hematopoietic cell transplantation for chronic myelogenous leukemia. 1527 2


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