Analysis of altered proteins related to blast crisis in chronic myeloid leukemia by proteomic study

Introduction: Chromic myeloid leukemia (CML) blast crisis (BC) and imatinib (IM) resistance is a significant barrier to the effective treatment of the disease. Methods: Expression profiles of differential proteins were identified, and new biomarkers or pathways related to BC in CML were screened through proteomic analysis. Total proteins from primary bone marrow cells of CML patients in chronic phase (CP) and BC were separated via two‐dimensional (2D) polyacrylamide gel electrophoresis and then analyzed by imagemaster 5.0 software to detect differential protein spots which were already identified by mass spectrometry. Based on the variation of the whole expression profile, some key proteins were picked out for Western blot to confirm the accuracy of proteomics data. Moreover, related signal pathways involving those proteins were investigated. Results: The result indicated that thirteen protein points between CML‐CP and CML‐BC were successfully determined. Results from Western blot of RhoA, hnRNPK, ANXA1, PSMB4, and LTA4H were similar to those from 2D polyacrylamide gel electrophoresis. Most of those proteins were involved in the proteosome pathway and the small G‐protein pathway. Conclusion: A group of proteins associated with BC can be obtained and the result of this study might provide clues for further research.     

Allogeneic hematopoietic stem cell transplantation for patients with chronic myeloid leukemia in second chronic phase attained by imatinib after onset of blast crisis

The prognosis for patients with chronic myeloid leukemia (CML) in blast crisis (BC) remains dismal even with the availability of the BCR-ABL tyrosine kinase inhibitor imatinib, since it only offers short-term benefit in most cases. Allogeneic hematopoietic stem cell transplantation (HSCT) seems to be a viable option for BC-CML patients who attained remission. We treated ten patients with ablative allogeneic HSCT, who achieved second chronic phase (CP) by the use of imatinib after onset of BC. Median patient age was 32 years (range 17–46). Among them, four patients received HSCT from human leukocyte antigen mismatched haplo-identical family donors. After a median follow-up of 24 months (range 8–42), six out of the ten patients were alive in durable complete cytogenetic remission, one patient died in relapse 4 months after transplantation, the others died of severe acute graft-versus-host disease and associated infections. No unusual organ toxicities and engraftment difficulties were observed. Extensive chronic GVHD developed in three of six patients who could be evaluated. Patients transplanted with haplo-identical donors had a high treatment-related modality. Allogeneic HSCT may represent a feasible treatment for patients with CML in second CP attained by imatinib after onset of BC especially when a suitable donor is available.     

Imatinib-induced decompensated heart failure in an elderly patient with chronic myeloid leukemia: case report and literature review

Because it is safe and well tolerated, imatinib is a standard first-line therapy for chronic myeloid leukemia (CML). Although there have been sporadic reports of imatinib-induced cardiotoxicity, including left ventricle (LV) dysfunction and heart failure, the evidence for it is contradictory. Here, we reported a case of an 88-year-old male patient with CML developed decompensated heart failure following imatinib therapy. Four days after the initiation of imatinib, the patient developed orthopnea, edema and a pleural effusion accompanied by abdominal distension, nausea and vomiting. The chest X-ray film showed an enlarged cardiac profile. The echocardiogram demonstrated a decreased LV ejection fraction and enlarged left-side cardiac chambers. B-type natriuretic peptide concentrations were markedly increased. The patient recovered soon after the withdrawal of imatinib and introduction of comprehensive therapy for heart failure. Imatinib-induced cardiotoxicity in elderly patients is a potentially serious complication that merits further evaluation.     

Megakaryocytic blast crisis as first presentation of chronic myeloid leukemia

We describe an extremely rare case of megakaryocytic blast crisis as first presentation of chronic myeloid leukemia. The patient had a very high platelet count and developed an ischemic stroke with seizures. She was treated with hydroxyurea, platelet apheresis, ARA-C, and idarubicin in order to obtain a prompt reduction of thrombocytosis and then with imatinib 600 mg/die PO. The therapy induced a complete hematological remission with a resolution of neurological signs within 4 weeks.     

Chronic myeloid leukemia presenting as gout

A 53-year-old man presented with gouty arthritis. A physical examination and haematological and biochemical tests showed that he had chronic myeloid leukemia. He was treated with allopurinol, hydroxyurea and analgesics. The arthritis subsided completely within 2 weeks. He continues in haematologic remission (on interferon) with no further recurrence of the gout. Received: 5 July 2000 / Accepted: 26 February 2001     

Managing resistance in chronic myeloid leukemia

Chronic myeloid leukemia (CML) is a myeloproliferative disorder that affects 5000 new patients per year in the United States. Prior to 10 years ago, durable remission was rare and patients often underwent bone marrow transplantation with substantial morbidity and mortality. Fortunately, CML has been the epicenter of exciting advances in cancer therapy with the discovery of the Bcr-Abl gene fusion and the subsequent development of imatinib mesylate, a small molecule tyrosine kinase inhibitor, to target the kinase activity of the bcr-abl protein product. Despite unprecedented durability for complete hematologic, cytogenetic, and molecular responses seen with front-line imatinib therapy, many patients require alternative therapy because of drug intolerance, suboptimal response, primary resistance, secondary resistance, or progression to advanced phase disease. Further, up to 5% of patients present with advanced disease that does not sustain a durable response to tyrosine kinase inhibitors. Thus, up to one third of CML patients require alternate therapy. Chronic myeloid leukemia has become an exemplary model system for understanding molecular targeting and overcoming mechanisms of drug resistance. This review will discuss potential mechanisms of resistance and ongoing research into novel targets and agents for CML resistant to standard of care.     

Chronic myeloid leukemia with minor-bcr breakpoint developed hybrid type of blast crisis

Although a breakpoint in the minor breakpoint cluster region (m-bcr) of the BCR gene is observed in about two-thirds of patients with Philadelphia chromosome-positive acute lymphoblastic leukemia, this type of genomic rearrangement occurs very rarely in chronic myeloid leukemia (CML). We describe here the eighth case of m-bcr CML, and delineate unique clinical characteristics found in common to the 7 cases reported previously. Monocytosis with a low neutrophil/monocyte ratio resembling chronic myelomonocytic leukemia was the most striking feature of m-bcr CML. Splenomegaly and basophilia were not conspicuous in chronic phase. A high percentage of immature granulocytes and low neutrophil alkaline phosphatase score were the findings in common with classical CML. Lymphoid and myeloid blast changes have been observed at and shortly after presentation so far. We found a hybrid type of blast crisis in the course of m-bcr CML.Thus, m-bcr CML may be a definite subtype of CML, exhibiting distinct clinical characteristics. The presence of fusion product of m-bcr mRNA in an earlier myeloid cell may involve monocytic lineage in addition to myeloproliferative defects. Am. J. Hematol. 57:320–325, 1998. © 1998 Wiley-Liss, Inc.     

T-lymphoid blast crisis in chronic myeloid leukemia

Chronic myeloid leukemia (CML) is considered to be a pleuripotential stem cell disorder with the capacity to differentiate into myeloid, erythroid, megakaryocytic, and lymphoid cell lines. Consequently, blast crisis (BC) involving each of the above lineages has been well described. Among lymphoblastic crises, differentiation frequently occurs along B-cell lineage. We report four patients of CML who terminated in T-cell extramedullary BC in lymph nodes after a variable duration of chronic phase. The T-lineage was established by characteristic cytochemical staining and reactivity with a panel of anti-T-cell monoclonal antibodies. All four cases were Philadelphia (Ph) chromosome positive and demonstrated the Ph chromosome and associated anomalies (extra Ph, +19) in the lymph nodes. Our data adds to the growing evidence that CML is a disorder of the common stem cell from which T, B, and myeloid precursors originate.     

Phenotypic and genotypic switch in Philadelphia-positive, BCR-positive blast crisis of chronic myeloid leukemia.

Abstract: We report a case of Ph1-positive, bcr-positive chronic myeloid leukemia blast crisis (CML-BC) which at presentation showed a mixed myeloid/B-lymphoid immunophenotype along with TdT positivity and, at the molecular level, an oligoclonal rearrangement of the immunoglobulin heavy chain (IgH) gene region. After obtaining a successful remission, at the time of relapse the patient underwent a phenotypic and genotypic switch from mixed to myeloid phenotype, characterized by the loss of the lymphoid markers and TdT expression and by a germline configuration of the IgH gene region. The same bcr rearrangement was, however, found in both phases of the disease, supporting the suggestion of a true phenotypic and genotypic conversion. This report confirms that the neoplastic event in CML may take place at an early multipotent stem-cell level, prior to a well-defined phenotypic and genotypic lineage expression. Moreover, it is suggested that different factors (chemotherapy? growth factors?) may have either eradicated the bcr⁺ /IgH⁺ clone and promoted the growth of bcr⁺ /IgH^? leukemic cells or, alternatively, supported the lymphoid differentiation program and induced a myeloid lineage shift.     

Disseminated intravascular coagulation and decrease in fibrinogen levels induced by vincristine/prednisolone therapy of lymphoid blast crisis of chronic myeloid leukemia

Summary Therapy with vincristine (2 mg i.v. weekly) and prednisolone (100 mg p.o. daily) caused a decrease in fibrinogen levels in nine patients treated for lymphoid blast crisis (LBC) of chronic myeloid leukemia (CML). During the first days of treatment disseminated intravascular coagulation (DIC), evidenced by a positive ethanol gelation test, markedly increased thrombin-antithrombin III complex and fibrin-split product D-dimer levels, and a rapid fall in fibrinogen levels was observed in two patients. The induction of DIC in these two patients caused profuse bleeding in one and necessitated substitution therapy with fibrinogen and platelet concentrates. The remaining seven patients revealed no signs of DIC; nevertheless, four of them showed a moderate increase in D-dimer levels after initiation of therapy. In these patients a well-known side effect of long-term steroid therapy, namely a decrease of fibrinogen levels, was observed within the first week of treatment. Fibrinogen levels did not fall below 150 mg/dl and increased after dose reduction from 100 mg/day to 50 mg/day. We conclude from our results that two types of disturbances in fibrinogen metabolism can be observed during vincristine/prednisolone therapy of LBC of CML: (a) a decrease of fibrinogen levels due to a steroid-mediated impairement of liver synthesis, and (b) a rapid fall in fibrinogen levels in the course of DIC, most likely induced by the release of procoagulants from detoriorating blast cells, leading to severe bleeding in selected cases.     

High-dose cytosine arabinoside and idarubicin treatment of chronic myeloid leukemia in myeloid blast crisis

Chronic myeloid leukemia in myeloid blast crisis (CML-MBC) is highly resistant to standard induction chemotherapy regimens. Anecdotal results from previous clinical trials support the concept of dose escalation in patients with CML-MBC. Eight patients with CML-MBC were treated with cytosine arabinoside (Ara-C) 1.5-3.0 g/m2 intravenously over 1 hr every 12 hr for 12 doses and idarubicin 12 mg/m2 intravenously daily for 3 days. Sixteen previous reports describing the use of Ara-C-based chemotherapy regimens in patients with CML-MBC were also reviewed. Our patients' median age was 62 years (range, 42-69 years). One patient achieved complete hematologic remission (95% confidence interval, 0.3%, 53%). The median survival for our patients was 7.3 months. These results were not different from previous published reports using Ara-C-based chemotherapy regimens to treat CML-MBC. In summary, the combination of high-dose Ara-C and idarubicin did not improve the overall prognosis of patients with CML-MBC. Innovative approaches need to be explored for this patient population.     

Unusual location of BCR-ABL1 fusion sequences in a chronic myeloid leukemia patient

Abstract

We describe a case of a chronic myeloid leukemia patient displaying the chimeric BCR-ABL1 gene on 12p11. Chromosome analysis revealed complex chromosome aberration involving chromosomes 9, 12, and 22. Fluorescence in situ hybridization revealed an unusual signal pattern revealing the BCR-ABL1 fusion signal on chromosome 12, while no reciprocal ABL1-BCR fusion was detected on der(9) chromosome. The relocation of BCR-ABL1 fusion sequences to 12p11 site in our patient represents a rare type of variant translocation, as in almost all patients the chimeric BCR-ABL1 gene is located on der(22) chromosome. Our case illustrates the challenge of recognizing a complex pattern of cytogenetic aberrations that occur with variant t(9;22) and may add further information about clinical significance of unusual variant Ph rearrangements in CML patients receiving tyrosine kinase inhibitor treatment.     

Successful allogeneic bone marrow transplantation after reversion to chronic phase of blast crisis in chronic myeloid leukemia

A female with chronic myeloid leukemia (XX Ph 1 +) in blast crisis (localized to pleura and lymph nodes) was treated by polychemotherapy. After reversion to the chronic phase, an allogeneic bone marrow transplantation (BMT) was performed. Sixteen months after BMT, no sign of the disease was present (XY Ph 1 -).     

Efficacy and prognosis of chronic myeloid leukemia treated with imatinib mesylate in a Chinese population

There is limited data from developing countries on the current status of imatinib treatment for chronic myeloid leukemia (CML), thus we retrospectively analyzed 116 Chinese CML patients who received imatinib between 2003 and 2008. The response rates for 102 patients in chronic phase were: complete hematologic, 94.1%; complete cytogenetic, 69.6%; and complete molecular response, 54.9%. For 14 patients in the accelerated phase, the respective response rates were 85.7, 35.7 and 28.6%. The 3-year progression-free survival and 5-year overall survival were 73.3 and 74.8%. Although skin hypopigmentation occurs as the most common side effect (77.6%), imatinib is still well tolerated. In addition to the known pretreatment characteristics of spleen size, leukocyte and platelet counts, disease phase and Sokal scores, we found that delayed therapy, variant Philadelphia chromosome translocations and IM-related grade 3/4 leucopenia were associated with an inferior cytogenetic response. Four factors emerged as predictors of disease progression: molecular response, cytogenetic response, disease phase and disease duration prior to imatinib treatment, but only the latter three remained significant after multivariate analysis. The results indicate that the suboptimal outcome in Chinese patients is associated with delayed imatinib therapy, so the importance of the optimal treatment opportunity for CML should be emphasized.     

Association of MDR1 gene polymorphism (G2677T) with imatinib response in Egyptian chronic myeloid leukemia patients

Background

Despite the excellent efficacy results of imatinib treatment in CML patients, resistance to imatinib has emerged as a significant problem. Genetic variations in genes involved in drug transportation might influence the pharmacokinetic and metabolism of imatinib. The genotype of a patient is increasingly recognized in influencing the response to the treatment.

Aim

To investigate the genotype frequencies of single nucleotide polymorphisms (SNPs) G2677T in CML patients undergoing imatinib treatment to determine whether different genotype pattern of these SNPs have any influence in mediating response to imatinib.

Methods

A total of 96 CML and 90 control samples were analyzed for the human multidrug resistance gene 1 (MDR1) gene polymorphism (G2677T) using polymerase chain reaction-restriction fragment length polymorphism technique.

Results

Genotype distribution revealed a significant lower frequency of TT genotype in CML patients and non-significant difference in the GG, GT genotype frequencies between patients and controls (P = 0.004, 0.138, 0.210, respectively). GG genotype was significantly higher in chronic phase (P = 0.046), while GT genotype was significantly higher in Blastic crisis phase (P = 0.002). There was a significant difference in genotype frequency of G2677T among patients showing response and resistance to imatinib in chronic phase (P = 0.02). TT genotype was associated with complete hematological response (P = 0.01), complete cytogenetic response (P < 0.001), and better molecular response with a significant association (P < 0.001). GT genotype was associated with partial hematological response (P = 0.01) and minor cytogenetic response (P < 0.001). Optimal and suboptimal responses were observed for patients with TT genotype (P = 0.003). Failure of drug response was associated with GT genotype (P = 0.02); however, GG had no association with drug response. Multivariate analysis considered GT genotype as independent risk factor for resistance (P = 0.037), while TT genotype as protective factor against resistance to imatinib (P = 0.008).

Conclusion

Determination of MDR1 polymorphisms (G2677T) might be useful in response prediction to therapy with imatinib in patients with CML.     

Efficacy and Safety of Imatinib Mesylate for Patients in the First Chronic Phase of Chronic Myeloid Leukemia: Results of a Japanese Phase II Clinical Study

Imatinib mesylate is a relatively new drug that targets the BCR-ABL chimeric protein, the molecular basis of chronic myeloid leukemia (CML). A phase II clinical trial in 39 Japanese patients in the first chronic phase of CML was conducted with imatinib mesylate at a dose of 400 mg/day. Hematologic complete response was obtained in 92.3% of the patients, complete cytogenetic response (CR) was obtained in 43.6%, and major partial CR was obtained in 20.5% of the patients. Although 29 of 39 patients required an adjustment of dosing because of grade 3 or 4 adverse events, most of the events were reversible, and 25 of the 29 patients were able to resume therapy. Between day 15 and day 35, grade 3 or 4 neutropenia and/or leukocytopenia occurred in 13 patients, and grade 3 thrombocytopenia occurred in 5 patients. Overall, nonhematologic grade 3 adverse events occurred in 28.2% of the patients. These data support the use of imatinib mesylate as the treatment of choice for chronic-phase CML patients.