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Find video protocols related to scientific articles indexed in Pubmed.
Next-generation deep sequencing improves detection of BCR-ABL1 kinase domain mutations emerging under tyrosine kinase inhibitor treatment of chronic myeloid leukemia patients in chronic phase.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 09-19-2014
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Here, we studied whether amplicon next-generation deep sequencing (NGS) could improve the detection of emerging BCR-ABL1 kinase domain mutations in chronic phase chronic myeloid leukemia (CML) patients under tyrosine kinase inhibitor (TKI) treatment and discussed the clinical relevance of such sensitive mutational detection.
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LASP1 is a novel BCR-ABL substrate and a phosphorylation-dependent binding partner of CRKL in chronic myeloid leukemia.
Oncotarget
PUBLISHED: 06-11-2014
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Chronic myeloid leukemia (CML) is characterized by a genomic translocation generating a permanently active BCR-ABL oncogene with a complex pattern of atypically tyrosine-phosphorylated proteins that drive the malignant phenotype of CML. Recently, the LIM and SH3 domain protein 1 (LASP1) was identified as a component of a six gene signature that is strongly predictive for disease progression and relapse in CML patients. However, the underlying mechanisms why LASP1 expression correlates with dismal outcome remained unresolved. Here, we identified LASP1 as a novel and overexpressed direct substrate of BCR-ABL in CML. We demonstrate that LASP1 is specifically phosphorylated by BCR-ABL at tyrosine-171 in CML patients, which is abolished by tyrosine kinase inhibitor therapy. Further studies revealed that LASP1 phosphorylation results in an association with CRKL - another specific BCR-ABL substrate and bona fide biomarker for BCR-ABL activity. pLASP1-Y171 binds to non-phosphorylated CRKL at its SH2 domain. Accordingly, the BCR-ABL-mediated pathophysiological hyper-phosphorylation of LASP1 in CML disrupts normal regulation of CRKL and LASP1, which likely has implications on downstream BCR-ABL signaling. Collectively, our results suggest that LASP1 phosphorylation might serve as an additional candidate biomarker for assessment of BCR-ABL activity and provide a first step toward a molecular understanding of LASP1 function in CML.
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Distinct characteristics of e13a2 versus e14a2 BCR-ABL1 driven chronic myeloid leukemia under first-line therapy with imatinib.
Haematologica
PUBLISHED: 05-16-2014
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The vast majority of chronic myeloid leukemia patients express a BCR-ABL1 fusion gene mRNA encoding a 210 kDa tyrosine kinase which promotes leukemic transformation. A possible differential impact of the corresponding BCR-ABL1 transcript variants e13a2 ("b2a2") and e14a2 ("b3a2") on disease phenotype and outcome is still a subject of debate. A total of 1105 newly diagnosed imatinib-treated patients were analyzed according to transcript type at diagnosis (e13a2, n=451; e14a2, n=496; e13a2+e14a2, n=158). No differences regarding age, sex, or Euro risk score were observed. A significant difference was found between e13a2 and e14a2 when comparing white blood cells (88 vs. 65 × 10(9)/L, respectively; P<0.001) and platelets (296 vs. 430 × 10(9)/L, respectively; P<0.001) at diagnosis, indicating a distinct disease phenotype. No significant difference was observed regarding other hematologic features, including spleen size and hematologic adverse events, during imatinib-based therapies. Cumulative molecular response was inferior in e13a2 patients (P=0.002 for major molecular response; P<0.001 for MR4). No difference was observed with regard to cytogenetic response and overall survival. In conclusion, e13a2 and e14a2 chronic myeloid leukemia seem to represent distinct biological entities. However, clinical outcome under imatinib treatment was comparable and no risk prediction can be made according to e13a2 versus e14a2 BCR-ABL1 transcript type at diagnosis. (clinicaltrials.gov identifier:00055874).
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Equivalence of BCR-ABL transcript levels with complete cytogenetic remission in patients with chronic myeloid leukemia in chronic phase.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 04-29-2014
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Chronic myeloid leukemia (CML) patients are monitored by both cytogenetic and molecular assessments, although present guidelines appear to switch from cytogenetic to molecular criteria. Due to the increasing use of molecular measurements, it was the aim of this work to identify a BCR-ABL level according to the international scale (BCR-ABL(IS)) as an equivalent substitute for complete cytogenetic remission (CCyR).
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Dasatinib.
Recent Results Cancer Res.
PUBLISHED: 04-24-2014
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Dasatinib is an orally available short-acting dual ABL/SRC tyrosine kinase inhibitor (TKI). It potently inhibits BCR-ABL and SRC family kinases (SRC, LCK, YES, FYN), but also c-KIT, PDGFR-? and PDGFR-?, and ephrin receptor kinase. Dasatinib is an effective treatment for chronic myeloid leukemia (CML) and Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ ALL). Both diseases are characterized by a constitutively active tyrosine kinase; BCR-ABL. Dasatinib inhibits BCR-ABL with greater potency compared with other BCR-ABL inhibitors and is active in CML resistant or intolerant to imatinib. Dasatinib is approved for the treatment of CML (all phases) and for the treatment of Ph+ ALL, resistant or intolerant to prior imatinib treatment. Randomized trial data in CML show that first-line dasatinib provides superior responses compared with imatinib and enables patients to achieve early, deep responses, correlated with improved longer-term outcomes. A once-daily dose of 100 mg in chronic phase CML results in high hematologic and molecular remission rates and prolongation of survival. In accelerated and blastic phase of CML, as well as in Ph+ ALL, complete hematologic and cytogenetic remissions frequently occur. Remissions however are very short. In these patients, once-daily 140 mg is the recommended dose. The effect of dasatinib in other malignancies including solid tumors is subject of clinical studies. Regardless of many clinical trials in different tumor types and in different combinations of dasatinib with other agents, the role of dasatinib in the treatment of solid tumors has not yet been defined. Side effects of dasatinib are frequent but mostly moderate and manageable and include cytopenias and pleural effusions. The review presents the preclinical and clinical activity of dasatinib with a focus on clinical studies in CML.
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Explaining survival differences between two consecutive studies with allogeneic stem cell transplantation in patients with chronic myeloid leukemia.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 03-19-2014
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In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.
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Efficacy and feasibility of cyclophosphamide combined with intermediate- dose or high-dose cytarabine for relapsed and refractory acute myeloid leukemia (AML).
J. Cancer Res. Clin. Oncol.
PUBLISHED: 03-12-2014
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Approximately, 70 % of adult patients with de novo acute myeloid leukemia (AML) achieve a complete remission (CR) while 10-20 % of AML are refractory to induction chemotherapy. Furthermore, a significant proportion of AML patients in CR will relapse during or after consolidation treatment. There is no evidence for a standard salvage regimen and most centers use a combination of an anthracycline and cytarabine (AraC). The aim of this study was to investigate the impact of two age-adjusted regimens containing AraC and cyclophosphamide applied for the treatment of relapsed or refractory AML.
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Paraneoplastic inflammation in myelodysplastic syndrome or bone marrow failure: case series with focus on 5-azacytidine and literature review.
Eur. J. Haematol.
PUBLISHED: 03-09-2014
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Myelodysplastic syndrome (MDS) comprises a heterogeneous group of clonal disorders of haematopoietic stem cells, characterised by dysplastic haematopoiesis and dysregulated apoptosis resulting in various degrees of cytopenia, whereas canonical cytologic, cytogenetic and histopathologic findings guiding the diagnosis MDS are widely accepted, the MDS-phenotype can be masked by coexisting/paraneoplastic immunologic disease. Autoimmune disorders have an estimated incidence of 10% among patients suffering from MDS and are causally related to increased morbidity and mortality, younger age at diagnosis and more complex genetics. Conversely, systemic inflammatory disorders may be an early manifestation of MDS, show good response to immunosuppressive therapy and frequently disappear during the course of specific haematologic therapy.
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Long-term outcome with dasatinib after imatinib failure in chronic-phase chronic myeloid leukemia: follow-up of a phase 3 study.
Blood
PUBLISHED: 02-25-2014
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We present long-term follow-up of a dasatinib phase 3 study of patients with imatinib-resistant/-intolerant chronic myeloid leukemia (CML). In the CA180-034 study, 670 patients with imatinib-resistant/-intolerant CML in chronic phase (CML-CP) received dasatinib 100 mg once daily, 50 mg twice daily, 140 mg once daily, or 70 mg twice daily. At 6 years, 188 (28%) of 670 patients remained on study treatment. Estimated 6-year protocol-defined progression-free survival (PFS) rates were 49%, 51%, 40%, and 47%, respectively, and estimated 6-year overall survival (OS) rates were 71%, 74%, 77%, and 70%, respectively (intent-to-treat population, including protocol-defined progression or death after discontinuation). Estimated 6-year rates of survival without transformation on study treatment were 76%, 80%, 83%, and 74%, respectively. Major molecular response was achieved in 43% (100 mg once daily) and 40% (all other arms) of patients by 6 years. Molecular and cytogenetic responses at 3 and 6 months were highly predictive of PFS and OS. Notably, estimated 6-year PFS rates based on ?1%, >1% to 10%, and >10% BCR-ABL transcripts at 3 months were 68%, 58%, and 26%, respectively. Most adverse events occurred by 2 years. Imatinib-resistant/-intolerant patients with CML-CP can experience long-term benefit with dasatinib therapy, particularly if achieving BCR-ABL ?10% at 3 months. This study was registered at ClinicalTrials.gov: NCT00123474.
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Older patients with chronic myeloid leukemia (?65 years) profit more from higher imatinib doses than younger patients: a subanalysis of the randomized CML-Study IV.
Ann. Hematol.
PUBLISHED: 02-14-2014
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The impact of imatinib dose on response rates and survival in older patients with chronic myeloid leukemia in chronic phase has not been studied well. We analyzed data from the German CML-Study IV, a randomized five-arm treatment optimization study in newly diagnosed BCR-ABL-positive chronic myeloid leukemia in chronic phase. Patients randomized to imatinib 400 mg/day (IM400) or imatinib 800 mg/day (IM800) and stratified according to age (?65 years vs. <65 years) were compared regarding dose, response, adverse events, rates of progression, and survival. The full 800 mg dose was given after a 6-week run-in period with imatinib 400 mg/day. The dose could then be reduced according to tolerability. A total of 828 patients were randomized to IM400 or IM800. Seven hundred eighty-four patients were evaluable (IM400, 382; IM800, 402). One hundred ten patients (29 %) on IM400 and 83 (21 %) on IM800 were ?65 years. The median dose per day was lower for patients ?65 years on IM800, with the highest median dose in the first year (466 mg/day for patients ?65 years vs. 630 mg/day for patients <65 years). Older patients on IM800 achieved major molecular remission and deep molecular remission as fast as younger patients, in contrast to standard dose imatinib with which older patients achieved remissions much later than younger patients. Grades 3 and 4 adverse events were similar in both age groups. Five-year relative survival for older patients was comparable to that of younger patients. We suggest that the optimal dose for older patients is higher than 400 mg/day. ClinicalTrials.gov identifier: NCT00055874
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Safety and efficacy of switching to nilotinib 400 mg twice daily for patients with chronic myeloid leukemia in chronic phase with suboptimal response or failure on front-line imatinib or nilotinib 300 mg twice daily.
Haematologica
PUBLISHED: 02-14-2014
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In a randomized, phase III trial of nilotinib versus imatinib in patients with newly diagnosed Philadelphia chromosome positive chronic myeloid leukemia in chronic phase, more patients had suboptimal response or treatment failure on front-line imatinib than on nilotinib. Patients with suboptimal response/treatment failure on imatinib 400 mg once or twice daily or nilotinib 300 mg twice daily could enter an extension study to receive nilotinib 400 mg twice daily. After a 19-month median follow up, the safety profile of nilotinib 400 mg twice daily in patients switching from imatinib (n=35) was consistent with previous reports, and few new adverse events occurred in patients escalating from nilotinib 300 mg twice daily (n=19). Of patients previously treated with imatinib or nilotinib 300 mg twice daily, respectively, 15 of 26 (58%) and 2 of 6 (33%) without complete cytogenetic response at extension study entry, and 11 of 34 (32%) and 7 of 18 (39%) without major molecular response at extension study entry, achieved these responses at any time on nilotinib 400 mg twice daily. Estimated 18-month rates of freedom from progression and overall survival after entering the extension study were lower for patients switched from imatinib (85% and 87%, respectively) versus nilotinib 300 mg twice daily (95% and 94%, respectively). Nilotinib dose escalation was generally well tolerated and improved responses in about one-third of patients with suboptimal response/treatment failure. Switch to nilotinib improved responses in some patients with suboptimal response/treatment failure on imatinib, but many did not achieve complete cytogenetic response (clinicaltrials.gov identifiers: 00718263, 00471497 - extension).
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Mitomycin C and capecitabine in pretreated patients with metastatic gastric cancer: a multicenter phase II study.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 01-28-2014
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We conducted a multicenter phase II study to assess the toxicity and efficacy of a combination of mitomycin C (MMC) and capecitabine in pretreated patients with metastatic or locally advanced gastric cancer.
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Targeting the phosphoinositide 3-kinase pathway in hematologic malignancies.
Haematologica
PUBLISHED: 01-16-2014
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The phosphoinositide 3-kinase pathway represents an important anticancer target because it has been implicated in cancer cell growth, survival, and motility. Recent studies show that PI3K may also play a role in the development of resistance to currently available therapies. In a broad range of cancers, various components of the phosphoinositide 3-kinase signaling axis are genetically modified, and the pathway can be activated through many different mechanisms. The frequency of genetic alterations in the phosphoinositide 3-kinase pathway, coupled with the impact in oncogenesis and disease progression, make this signaling axis an attractive target in anticancer therapy. A better understanding of the critical function of the phosphoinositide 3-kinase pathway in leukemias and lymphomas has led to the clinical evaluation of novel rationally designed inhibitors in this setting. Three main categories of phosphoinositide 3-kinase inhibitors have been developed so far: agents that target phosphoinositide 3-kinase and mammalian target of rapamycin (dual inhibitors), pan-phosphoinositide 3-kinase inhibitors that target all class I isoforms, and isoform-specific inhibitors that selectively target the ?, -?, -?, or -? isoforms. Emerging data highlight the promise of phosphoinositide 3-kinase inhibitors in combination with other therapies for the treatment of patients with hematologic malignancies. Further evaluation of phosphoinositide 3-kinase inhibitors in first-line or subsequent regimens may improve clinical outcomes. This article reviews the role of phosphoinositide 3-kinase signaling in hematologic malignancies and the potential clinical utility of inhibitors that target this pathway.
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Early molecular response predicts outcomes in patients with chronic myeloid leukemia in chronic phase treated with frontline nilotinib or imatinib.
Blood
PUBLISHED: 12-11-2013
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We explored the impact of early molecular response (EMR; BCR-ABL ? 10% on the international scale [BCR-ABL(IS)] at 3 or 6 months) on outcomes in patients with newly diagnosed chronic myeloid leukemia in chronic phase treated with nilotinib or imatinib, based on 4 years of follow-up in ENESTnd (NCT00471497). Patients (N = 846) received nilotinib 300 mg twice daily, nilotinib 400 mg twice daily, or imatinib 400 mg once daily. At 3 months, more patients had EMR failure (ie, BCR-ABL(IS) > 10%) on imatinib (33%) than on nilotinib (9%-11%); similarly at 6 months, 16% of patients in the imatinib arm vs 3% and 7% in the nilotinib arms had EMR failure. In all arms, EMR failure was associated with lower rates of molecular response, an increased risk of progression, and lower overall survival compared with EMR achievement. We also analyzed patient and treatment characteristics associated with EMR and found distinct patterns in the nilotinib arms vs the imatinib arm. High Sokal risk score was associated with a high rate of EMR failure on imatinib, but not on nilotinib. In contrast, reduced dose intensity and dose interruptions were strongly associated with EMR failure in nilotinib-treated, but not imatinib-treated, patients. This study is registered at clinicaltrials.gov, identifier: NCT00471497.
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Early response with dasatinib or imatinib in chronic myeloid leukemia: 3-year follow-up from a randomized phase 3 trial (DASISION).
Blood
PUBLISHED: 12-05-2013
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This analysis explores the impact of early cytogenetic and molecular responses on the outcomes of patients with chronic myeloid leukemia in chronic phase (CML-CP) in the phase 3 DASISION trial with a minimum follow-up of 3 years. Patients with newly diagnosed CML-CP were randomized to receive 100 mg dasatinib (n = 259) or 400 mg imatinib (n = 260) once daily. The retrospective landmark analysis included patients evaluable at the relevant time point (3, 6, or 12 months). Median time to complete cytogenetic response was 3 versus 6 months with dasatinib versus imatinib. At 3 and 6 months, the proportion of patients with BCR-ABL transcript levels ? 10% was higher in the dasatinib arm. Deeper responses at 3, 6, and 12 months were observed in a higher proportion of patients on dasatinib therapy and were associated with better 3-year progression-free survival (PFS) and overall survival (OS) in both arms. First-line dasatinib resulted in faster and deeper responses compared with imatinib. The achievement of an early molecular response was predictive of improved PFS and OS, supporting new milestones for optimal response in patients with early CML-CP treated with tyrosine kinase inhibitors. This study was registered at ClinicalTrials.gov: NCT00481247.
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Potential mechanisms of disease progression and management of advanced-phase chronic myeloid leukemia.
Leuk. Lymphoma
PUBLISHED: 11-12-2013
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Despite vast improvements in the treatment of Philadelphia chromosome-positive chronic myeloid leukemia (CML) in chronic phase (CP), advanced stages of CML, accelerated phase or blast crisis, remain notoriously difficult to treat. Treatments that are highly effective against CML-CP produce disappointing results against advanced disease. Therefore, a primary goal of therapy should be to maintain patients in CP for as long as possible, by (1) striving for deep, early molecular response to treatment; (2) using tyrosine kinase inhibitors that lower risk of disease progression; and (3) more closely observing patients who demonstrate cytogenetic risk factors at diagnosis or during treatment.
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The KIT D816V expressed allele burden for diagnosis and disease monitoring of systemic mastocytosis.
Ann. Hematol.
PUBLISHED: 10-15-2013
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The activating KIT D816V mutation plays a central role in the pathogenesis, diagnosis, and targeted treatment of systemic mastocytosis (SM). For improved and reliable identification of KIT D816V, we have developed an allele-specific quantitative real-time PCR (RQ-PCR) with an enhanced sensitivity of 0.01-0.1 %, which was superior to denaturing high-performance liquid chromatography (0.5-1 %) or conventional sequencing (10-20 %). Overall, KIT D816 mutations were identified in 146/147 (99 %) of patients (D816V, n?=?142; D816H, n?=?2; D816Y, n?=?2) with SM, including indolent SM (ISM, n?=?63, 43 %), smoldering SM (n?=?8, 5 %), SM with associated hematological non-mast cell lineage disease (SM-AHNMD, n?=?16, 11 %), and aggressive SM/mast cell leukemia?±?AHNMD (ASM/MCL, n?=?60, 41 %). If positive in BM, the KIT D816V mutation was found in PB of all patients with advanced SM (SM-AHNMD, ASM, and MCL) and in 46 % (23/50) of patients with ISM. There was a strong correlation between the KIT D816V expressed allele burden (KIT D816V EAB) with results obtained from DNA by genomic allele-specific PCR and also with disease activity (e.g., serum tryptase level), disease subtype (e.g., indolent vs. advanced SM) and survival. In terms of monitoring of residual disease, qualitative and quantitative assessment of KIT D816V and KIT D816V EAB was successfully used for sequential analysis after chemotherapy or allogeneic stem cell transplantation. We therefore conclude that RQ-PCR assays for KIT D816V are useful complimentary tools for diagnosis, disease monitoring, and evaluation of prognosis in patients with SM.
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Adjuvant chemotherapy with gemcitabine and long-term outcomes among patients with resected pancreatic cancer: the CONKO-001 randomized trial.
JAMA
PUBLISHED: 10-10-2013
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The prognosis for patients with pancreatic cancer is poor, even after resection with curative intent. Gemcitabine-based chemotherapy is standard treatment for advanced pancreatic cancer, but its effect on survival in the adjuvant setting has not been demonstrated.
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Effect of the tyrosine kinase inhibitor nilotinib in patients with hypereosinophilic syndrome/chronic eosinophilic leukemia: analysis of the phase 2, open-label, single-arm A2101 study.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 09-11-2013
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Hypereosinophilic syndrome (HES) and chronic eosinophilic leukemia (CEL) are characterized by sustained overproduction of eosinophils and organ dysfunction. CEL involves the presence of clonal genetic markers, such as a fusion of FIP1-like 1 protein and platelet-derived growth factor receptor ? (FIP1L1-PDGFR?, or F/P) or PDGFR?-activating mutations.
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Comprehensive mutational profiling in advanced systemic mastocytosis.
Blood
PUBLISHED: 08-19-2013
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To explore mechanisms contributing to the clinical heterogeneity of systemic mastocytosis (SM) and to suboptimal responses to diverse therapies, we analyzed 39 KIT D816V mutated patients with indolent SM (n = 10), smoldering SM (n = 2), SM with associated clonal hematologic nonmast cell lineage disorder (SM-AHNMD, n = 5), and aggressive SM (n = 15) or mast cell leukemia (n = 7) with (n = 18) or without (n = 4) AHNMD for additional molecular aberrations. We applied next-generation sequencing to investigate ASXL1, CBL, IDH1/2, JAK2, KRAS, MLL-PTD, NPM1, NRAS, TP53, SRSF2, SF3B1, SETBP1, U2AF1 at mutational hotspot regions, and analyzed complete coding regions of EZH2, ETV6, RUNX1, and TET2. We identified additional molecular aberrations in 24/27 (89%) patients with advanced SM (SM-AHNMD, 5/5; aggressive SM/mast cell leukemia, 19/22) whereas only 3/12 (25%) indolent SM/smoldering SM patients carried one additional mutation each (U2AF1, SETBP1, CBL) (P < .001). Most frequently affected genes were TET2, SRSF2, ASXL1, CBL, and RUNX1. In advanced SM, 21/27 patients (78%) carried ?3 mutations, and 11/27 patients (41%) exhibited ?5 mutations. Overall survival was significantly shorter in patients with additional aberrations as compared to those with KIT D816V only (P = .019). We conclude that biology and prognosis in SM are related to the pattern of mutated genes that are acquired during disease evolution.
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Younger patients with chronic myeloid leukemia do well in spite of poor prognostic indicators: results from the randomized CML study IV.
Ann. Hematol.
PUBLISHED: 07-25-2013
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Since the advent of tyrosine kinase inhibitors, the impact of age on outcome of chronic myeloid leukemia (CML) patients has changed. We therefore analyzed patients from the randomized CML study IV to investigate disease manifestations and outcome in different age groups. One thousand five hundred twenty-four patients with BCR-ABL-positive chronic phase CML were divided into four age groups: (1) 16-29 years, n?=?120; (2) 30-44 years, n?=?383; (3) 45-59 years, n?=?495; and (4)??60 years, n?=?526. Group 1 (adolescents and young adults (AYAs)) presented with more aggressive disease features (larger spleen size, more frequent symptoms of organomegaly, higher white blood count, higher percentage of peripheral blasts and lower hemoglobin levels) than the other age groups. In addition, a higher rate of patients with BCR-ABL transcript levels >10 % on the international scale (IS) at 3 months was observed. After a median observation time of 67.5 months, no inferior survival and no differences in cytogenetic and molecular remissions or progression rates were observed. We conclude that AYAs show more aggressive features and poor prognostic indicators possibly indicating differences in disease biology. This, however, does not affect outcome.
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The development of dasatinib as a treatment for chronic myeloid leukemia (CML): from initial studies to application in newly diagnosed patients.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 07-22-2013
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Dasatinib is a dual Abl/Src tyrosine kinase inhibitor (TKI) designed as a prototypic short-acting BCR-ABL-targeted TKI that inhibits BCR-ABL with greater potency compared with imatinib, nilotinib, bosutinib, and ponatinib and has been shown to have potential immunomodulatory effects. Dasatinib is approved for the treatment of all phases of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia resistant or intolerant to prior imatinib treatment and first-line treatment for CML in chronic phase. In this article, the development of dasatinib as a treatment for patients with CML is reviewed.
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European LeukemiaNet recommendations for the management of chronic myeloid leukemia: 2013.
Blood
PUBLISHED: 06-26-2013
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Advances in chronic myeloid leukemia treatment, particularly regarding tyrosine kinase inhibitors, mandate regular updating of concepts and management. A European LeukemiaNet expert panel reviewed prior and new studies to update recommendations made in 2009. We recommend as initial treatment imatinib, nilotinib, or dasatinib. Response is assessed with standardized real quantitative polymerase chain reaction and/or cytogenetics at 3, 6, and 12 months. BCR-ABL1 transcript levels ?10% at 3 months, <1% at 6 months, and ?0.1% from 12 months onward define optimal response, whereas >10% at 6 months and >1% from 12 months onward define failure, mandating a change in treatment. Similarly, partial cytogenetic response (PCyR) at 3 months and complete cytogenetic response (CCyR) from 6 months onward define optimal response, whereas no CyR (Philadelphia chromosome-positive [Ph+] >95%) at 3 months, less than PCyR at 6 months, and less than CCyR from 12 months onward define failure. Between optimal and failure, there is an intermediate warning zone requiring more frequent monitoring. Similar definitions are provided for response to second-line therapy. Specific recommendations are made for patients in the accelerated and blastic phases, and for allogeneic stem cell transplantation. Optimal responders should continue therapy indefinitely, with careful surveillance, or they can be enrolled in controlled studies of treatment discontinuation once a deeper molecular response is achieved.
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The BCR-ABLT315I mutation compromises survival in chronic phase chronic myelogenous leukemia patients resistant to tyrosine kinase inhibitors, in a matched pair analysis.
Haematologica
PUBLISHED: 05-28-2013
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The BCR-ABL T315I mutation confers resistance to currently licensed tyrosine kinase inhibitors in chronic myelogenous leukemia. However, the impact of this mutation on survival in early stages of disease, in chronic phase, has never been detailed. Using matched pair analysis, a cohort of 64 patients with chronic phase chronic myelogenous leukemia harboring a T315I mutation and resistant to imatinib mesylate was compared to a similar cohort of 53 chronic phase patients resistant to imatinib, but with no detectable T315I mutation, in the pre-ponatinib era. These patients were matched according to age at diagnosis, interval between disease diagnosis and start of imatinib treatment, and duration of imatinib therapy. Kaplan-Meier survival analyses demonstrated the significant negative impact of the presence of the T315I mutation on overall survival (since imatinib-resistance: 48.4 months for T315I(+) patients versus not reached for T315I(-) ones; P=0.006) and failure-free survival (since imatinib-resistance: 34.7 months for T315I(+) patients versus not reached for T315I(-) patients; P=0.003). In addition, Cox proportional hazard models adjusted on overall survival demonstrated the negative influence of the T315I mutation (P=0.02, HR=2.54). These results confirm early assumptions concerning the poor prognosis of chronic phase chronic myelogenous leukemia patients with the T315I mutation who are not eligible for allogeneic transplantation, and demonstrate the need for more therapeutic options.
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The E3 ubiquitin ligase TRAF2 can contribute to TNF-? resistance in FLT3-ITD-positive AML cells.
Leuk. Res.
PUBLISHED: 04-28-2013
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TNF-? has pleiotropic effects on cell survival and apoptosis. The E3 ubiquitin ligase TRAF2 plays a crucial role for TNF-? mediated signaling since NF-?B activation by TNF-? is at least partially mediated by TRAF2. The objective of this study was to investigate whether TNF-? can induce apoptosis in FLT3-ITD-positive AML cells and to elucidate the influence of TRAF2. Stable lentiviral mediated down-regulation of TRAF2 resulted in a decrease of phosphorylation of the anti-apoptotic protein AKT and its downstream target GSK-3?. Induction of apoptosis and impaired proliferation after TNF-? exposure were observed. Co-treatment of FLT3-ITD-positive cells with the specific FLT3 inhibitor AC220 was able to overcome TNF-? resistance. Taken together, we conclude that TRAF2 plays an important role in signal transduction and survival of AML cells.
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Lack of association of platelet-derived growth factor (PDGF) receptor autoantibodies and severity of chronic graft-versus-host disease (GvHD).
J. Cancer Res. Clin. Oncol.
PUBLISHED: 04-27-2013
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The existence of platelet-derived growth factor (PDGF) receptor autoantibodies in systemic sclerosis is conflicting, and such antibodies were also detected in patients with chronic graft-versus-host disease (GvHD) after allogeneic peripheral blood stem cell transplantation (PBSCT). We therefore aimed to screen for PDGF receptor autoantibodies in patients with chronic GvHD.
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Genotyping of 25 leukemia-associated genes in a single work flow by next-generation sequencing technology with low amounts of input template DNA.
Clin. Chem.
PUBLISHED: 04-16-2013
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We sought to establish a convenient, sensitive next-generation sequencing (NGS) method for genotyping the 26 most commonly mutated leukemia-associated genes in a single work flow and to optimize this method for low amounts of input template DNA.
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Improved tolerability by a modified intermittent treatment schedule of dasatinib for patients with chronic myeloid leukemia resistant or intolerant to imatinib.
Ann. Hematol.
PUBLISHED: 04-09-2013
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Intermittent dosing of dasatinib with a once daily regimen has been shown to reduce side effects while preserving clinical efficacy in early and advanced phase chronic myeloid leukemia (CML). Yet, hematologic toxicity and fluid retention demand a dose modification or treatment discontinuation in selected patients. Patients resistant or intolerant to imatinib were retrospectively evaluated based on the toxicity-guided administration of a dose-reduced dasatinib regimen. Patients were treated with an on/off regimen (3 to 5 days on, 2 to 4 days off) to allow regression of dasatinib-dependent off-target toxicity. Patients were followed up by routine hematologic and cytogenetic assessment and molecular monitoring to safeguard clinical response to the altered drug schedule. Thirty-three CML patients primarily in chronic phase with imatinib intolerance (n = 11) or resistance (n = 22) were investigated. Nonexclusive reasons for dose reduction were hematologic toxicity (17/33, 51%) and pleural effusions (18/33, 55%). On/off treatment with a weekend drug holiday significantly reduced pleural effusions and hematologic toxicity. Eighteen of 31 (58%) patients showed effective disease control despite reduced total weekly dasatinib doses, either demonstrated by achieving an improved response level (12/31) or keeping the response level achieved by conventional continuous dosing (6/31). Of note, 10/12 patients with subsequently improved response have been treated for a minimum of 6 months with continuous dosing dasatinib regimens without having achieved the response level achieved after allowing drug holiday. Weekend treatment interruption of dasatinib allows continuation of dasatinib treatment for patients suffering from side effects. These data mandate prospective investigation of alternative intermittent targeting regimens.
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Subcutaneous omacetaxine mepesuccinate in patients with chronic-phase chronic myeloid leukemia previously treated with 2 or more tyrosine kinase inhibitors including imatinib.
Clin Lymphoma Myeloma Leuk
PUBLISHED: 03-27-2013
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Omacetaxine mepesuccinate (omacetaxine) is a first-in-class cephalotaxine that has demonstrated efficacy in CML. In this analysis we evaluated omacetaxine in CML patients with resistance or intolerance to 2 or more tyrosine kinase inhibitors (TKIs).
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Nilotinib is associated with a reduced incidence of BCR-ABL mutations vs imatinib in patients with newly diagnosed chronic myeloid leukemia in chronic phase.
Blood
PUBLISHED: 03-15-2013
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In patients with chronic myeloid leukemia, BCR-ABL mutations contribute to resistance to tyrosine kinase inhibitor therapy. We examined the occurrence of treatment-emergent mutations and their impact on response in patients from the ENESTnd phase 3 trial. At the 3-year data cutoff, mutations were detected in approximately twice as many patients (21) on imatinib 400 mg once daily as on nilotinib (11 patients each on nilotinib 300 mg twice daily and nilotinib 400 mg twice daily). The majority of mutations occurred in patients with intermediate or high Sokal scores. Most mutations (14 [66.7%]) emerging during imatinib treatment were imatinib-resistant and nilotinib-sensitive. Incidence of the T315I mutation was low (found in 3, 2, and 3 patients on nilotinib 300 mg twice daily, nilotinib 400 mg twice daily, and imatinib, respectively) and mostly occurred in patients with high Sokal scores. Of the patients with emergent mutations, 1 of 11, 2 of 11, and 7 of 21 patients on nilotinib 300 mg twice daily, nilotinib 400 mg twice daily, and imatinib, respectively, progressed to accelerated phase/blast crisis (AP/BC) on treatment. Overall, nilotinib led to fewer treatment-emergent BCR-ABL mutations than imatinib and reduced rates of progression to AP/BC in patients with these mutations. (Clinicaltrials.gov NCT00471497).
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Impact of NOD2 polymorphisms on infectious complications following chemotherapy in patients with acute myeloid leukaemia.
Ann. Hematol.
PUBLISHED: 03-13-2013
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We sought to investigate the relationship between polymorphisms of the NOD2 gene and infectious complications following intensive induction chemotherapy in patients with acute myeloid leukaemia (AML). We hypothesised that single nucleotide polymorphisms (SNPs) of the NOD2 gene are associated with a higher rate of infections during the phase of severe neutropenia. In 131 AML patients receiving induction therapy, the presence of the three most frequent polymorphisms of NOD2 (Arg702Trp, Gly908Arg, Leu1007fsinsC) was analysed. SNP analyses by means of genomic PCR incorporating fluorescence-labelled probes with characteristic melting curves were performed using the LightCycler platform. Our data suggest a significantly lower probability of mucositis or enteritis in AML patients lacking any of the three evaluated NOD2 polymorphisms. Furthermore, bloodstream cultures of AML patients carrying either a missense or a frameshift mutation of NOD2 were significantly more frequently tested positive concerning Streptococcus spp. In contrast, the presence of NOD2 polymorphisms had no impact on such important infectious complications as systemic inflammatory response syndrome or sepsis, the rate of central venous catheter infections or the incidence of pneumonia including fungal infections. Our data represent one of the first reports investigating the impact of polymorphisms of the innate immune system on infectious complications in patients with neutropenia following chemotherapy. A correlation between NOD2 polymorphisms and infectious events in AML patients is demonstrated.
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Establishment and validation of analytical reference panels for the standardization of quantitative BCR-ABL1 measurements on the international scale.
Clin. Chem.
PUBLISHED: 03-07-2013
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Current guidelines for managing Philadelphia-positive chronic myeloid leukemia include monitoring the expression of the BCR-ABL1 (breakpoint cluster region/c-abl oncogene 1, non-receptor tyrosine kinase) fusion gene by quantitative reverse-transcription PCR (RT-qPCR). Our goal was to establish and validate reference panels to mitigate the interlaboratory imprecision of quantitative BCR-ABL1 measurements and to facilitate global standardization on the international scale (IS).
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Paradoxical MAPK-activation in response to treatment with tyrosine kinase inhibitors in CML: Flow cytometry loses track.
Cytometry B Clin Cytom
PUBLISHED: 02-19-2013
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BACKGROUND: Paradoxical activation of the MAP-kinases, ERK1, and ERK2 (ERK1/2) is observed in CML cell lines and primary CML patient cells treated with tyrosine kinase inhibitors (TKI) in vitro. The commonly accepted assumption is that activated ERK1/2 is key regulators of survival of leukemic cells treated with kinase inhibitors. Hence, paradoxical ERK1/2-activation may trigger resistance in vivo, which yet has to be shown. We therefore sought to establish a flow cytometric assay that enables us to measure paradoxical TKI-induced ERK1/2-activation on a single cell basis in primary CML cells. METHODS: Side-by-side Western blot and intracellular flow cytometry (FCM) after in vitro exposure of cell lines and primary cells to nilotinib were performed. Detailed analysis of pre-analytical factors and the issue of compartmentalization of phosphorylated ERK1/2 by confocal laser scanning microscopy were performed. RESULT: Results were conflicting in that pERK-activation was robustly detected in Western blot assays, but not when cells were analyzed by FCM despite well functioning positive and negative controls. This is in contrast to experiments on other targets such as phospho-CrkL, where also in our hands TKI-dependent inhibition of phosphorylation is trackable by both Western blot and FCM assays. CONCLUSIONS: To our knowledge this is the first report of discordant results in phospho-protein analysis in TKI-treated cells analyzed by Western blot vs. FCM. We speculate that a substance specific interaction interferes with fluorescence dependent methods seeking to track phosphorylated ERK1/2 in TKI-treated cells. © 2013 International Clinical Cytometry Society.
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Rapid initial decline in BCR-ABL1 is associated with superior responses to second-line nilotinib in patients with chronic-phase chronic myeloid leukemia.
BMC Cancer
PUBLISHED: 01-31-2013
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BACKGROUND: We evaluated BCR-ABL1 kinetics in patients treated with nilotinib and analyzed whether a dynamic model of changes in BCR-ABL1 levels over time could be used to predict long-term responses. METHODS: Patients from the nilotinib registration trial (CAMN107A2101; registered at www.clinicaltrials.gov as NCT00109707) who had imatinib-resistant or -intolerant Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) in chronic phase (CP) or accelerated phase with BCR-ABL1 greater than 10% (on the international scale [IS]) at baseline and, in the first 6 months, had at least three BCR-ABL1 transcript measurements and an average daily dose of at least 720 mg were included in this analysis (N equals 123). RESULTS: More than half of patients (65/123; 53 percent) had a slow monophasic response and the remainder (58/123; 47 percent) had a biphasic response, in which patients had a rapid initial decrease in BCR-ABL1 transcripts followed by a more gradual response. The biphasic response type strongly correlated with improved event-free survival (EFS). Data in the first 6 months of follow-up were sufficient to predict EFS at 24 months. CONCLUSIONS: Unlike newly diagnosed patients with Ph+ CML-CP--in whom the majority had a biphasic response--approximately half of patients with imatinib-resistant or -intolerant CML had a slower, monophasic response. Second-line patients who did have a biphasic response had an EFS outlook similar to that of newly diagnosed patients treated with imatinib. Our model was comparable to using BCR-ABL1 (IS) less than or equal to 10 percent at 6 months as a threshold for predicting EFS.
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Modelling cost effectiveness of horse antithymocyte globulin for treating severe aplastic anaemia in Germany.
Ann. Hematol.
PUBLISHED: 01-24-2013
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Acquired severe aplastic anaemia (AA) is a serious condition caused by immune-triggered bone marrow failure. For patients not eligible for bone marrow transplantation, treatment of choice is immunosuppression by a combined treatment with antithymocyte globulin (ATG) and cyclosporine. The debate on treatment optimization in AA is focused on conflicting data regarding ATG preparations from horse (h-ATG) versus rabbit (r-ATG), recently favouring h-ATG. H-ATG has been withdrawn from the European market in 2007. Reimbursement for imported preparations from outside Europe is frequently denied in negotiations with statutory health insurance companies. This raises the question of whether h-ATG is cost effective and a sensible investment with regard to healthcare budgets as well as patient health. We modelled the cost effectiveness of r-ATG versus h-ATG based on a recent randomized trial and cost data provided by the hospital pharmacy of Jena University Hospital. We calculated the amount of life years gained and the average incremental costs per life year gained when comparing h-ATG and r-ATG. Our calculations revealed average incremental costs per life year gained of 11,033.80 for the examined patient population treated with h-ATG when compared to r-ATG. Assuming a cost effectiveness threshold of 25,000-35,000 per life year gained, our calculations demonstrate cost effectiveness of h-ATG as compared to r-ATG.
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Effects of imatinib mesylate in patients with polycythemia vera: results of a phase II study.
Ann. Hematol.
PUBLISHED: 01-22-2013
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The antiproliferative effects of the tyrosine kinase inhibitor imatinib mesylate were reported in single cases with polycythemia vera (PV). We, therefore, conducted a clinical phase II study to assess the rate and quality of response in patients with PV. Thirty-one patients, with a median age of 64 years (range, 45-84 years), were included. All but one patient were on phlebotomy; 14 (45%) had previously received cytoreductive therapy. Imatinib was started with 400 mg/day. In 26% of patients, dose escalation up to 800 mg was performed. After a median treatment duration of 8.3 months (range, 0.1-62.1 months), the overall response rate was 55%. No complete remission (normalization of all parameters: hematocrit, white blood cell (WBC) count, platelet count, and spleen size determined by ultrasound examination) was reached because the spleen remained enlarged in all patients. Thirteen patients (42%) achieved partial remission (?25% reduction of at least one of the previously mentioned parameters); in 10 of these, the respective reduction was ?50%. In four patients (13%) with minor response, the reduction was <25%. No change or progressive disease was seen in 14 patients (45%). The nonresponders had a longer previous disease duration and had received more antecedent cytoreductive therapy (p?=?0.009). Compared to baseline characteristics, imatinib induced the reduction of phlebotomies (p?=?0.003), of WBC count (p?=?0.002), and of platelet count (p?=?0.04). Three patients became free from phlebotomies. In six investigated patients, no significant reduction of the JAK2V617F burden was observed despite clinical improvement. The results show that imatinib has moderate cytoreductive effects in PV.
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Differential effects of dosing regimen on the safety and efficacy of dasatinib: retrospective exposure-response analysis of a Phase III study.
Clin Pharmacol
PUBLISHED: 01-01-2013
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Dasatinib is a prototypic short half-life BCR-ABL1 tyrosine kinase inhibitor. The recommended dose of dasatinib for chronic myeloid leukemia in chronic phase was changed from 70 mg twice daily to 100 mg once daily following a Phase III dose-optimization study. To better understand the superior benefit-risk profile of dasatinib 100 mg once daily, exposure-response was characterized for efficacy (major cytogenetic response) and safety (pleural effusion).
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Educational session: managing chronic myeloid leukemia as a chronic disease.
Hematology Am Soc Hematol Educ Program
PUBLISHED: 12-14-2011
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Elucidation of the pathogenesis of chronic myeloid leukemia (CML) and the introduction of tyrosine kinase inhibitors (TKIs) has transformed this disease from being invariably fatal to being the type of leukemia with the best prognosis. Median survival associated with CML is estimated at > 20 years. Nevertheless, blast crisis occurs at an incidence of 1%-2% per year, and once this has occurred, treatment options are limited and survival is short. Due to the overall therapeutic success, the prevalence of CML is gradually increasing. The optimal management of this disease includes access to modern therapies and standardized surveillance methods for all patients, which will certainly create challenges. Furthermore, all available TKIs show mild but frequent side effects that may require symptomatic therapy. Adherence to therapy is the key prerequisite for efficacy of the drugs and for long-term success. Comprehensive information on the nature of the disease and the need for the continuous treatment using the appropriate dosages and timely information on efficacy data are key factors for optimal compliance. Standardized laboratory methods are required to provide optimal surveillance according to current recommendations. CML occurs in all age groups. Despite a median age of 55-60 years, particular challenges are the management of the disease in children, young women with the wish to get pregnant, and older patients. The main challenges in the long-term management of CML patients are discussed in this review.
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Dasatinib or imatinib in newly diagnosed chronic-phase chronic myeloid leukemia: 2-year follow-up from a randomized phase 3 trial (DASISION).
Blood
PUBLISHED: 12-09-2011
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Dasatinib is a highly potent BCR-ABL inhibitor with established efficacy and safety in imatinib-resistant/-intolerant patients with chronic myeloid leukemia (CML). In the phase 3 DASISION trial, patients with newly diagnosed chronic-phase (CP) CML were randomized to receive dasatinib 100 mg (n = 259) or imatinib 400 mg (n = 260) once daily. Primary data showed superior efficacy for dasatinib compared with imatinib after 12 months, including significantly higher rates of complete cytogenetic response (CCyR), confirmed CCyR (primary end point), and major molecular response (MMR). Here, 24-month data are presented. Cumulative response rates by 24 months in dasatinib and imatinib arms were: CCyR in 86% versus 82%, MMR in 64% versus 46%, and BCR-ABL reduction to ? 0.0032% (4.5-log reduction) in 17% versus 8%. Transformation to accelerated-/ blast-phase CML on study occurred in 2.3% with dasatinib versus 5.0% with imatinib. BCR-ABL mutations, assessed after discontinuation, were detected in 10 patients in each arm. In safety analyses, fluid retention, superficial edema, myalgia, vomiting, and rash were less frequent with dasatinib compared with imatinib, whereas pleural effusion and grade 3/4 thrombocytopenia were more frequent with dasatinib. Overall, dasatinib continues to show faster and deeper responses compared with imatinib, supporting first-line use of dasatinib in patients with newly diagnosed CML-CP. This study was registered at ClinicalTrials.gov: NCT00481247.
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Low BCR-ABL expression levels in hematopoietic precursor cells enable persistence of chronic myeloid leukemia under imatinib.
Blood
PUBLISHED: 11-18-2011
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BCR-ABL overexpression and stem cell quiescence supposedly contribute to the failure of imatinib mesylate (IM) to eradicate chronic myeloid leukemia (CML). However, BCR-ABL expression levels of persisting precursors and the impact of long-term IM therapy on the clearance of CML from primitive and mature bone marrow compartments are unclear. Here, we have shown that the number of BCR-ABL-positive precursors decreases significantly in all bone marrow compartments during major molecular remission (MMR). More importantly, we were able to demonstrate substantially lower BCR-ABL expression levels in persisting MMR colony-forming units (CFUs) compared with CML CFUs from diagnosis. Critically, lower BCR-ABL levels may indeed cause IM insensitivity, because primary murine bone marrow cells engineered to express low amounts of BCR-ABL were substantially less sensitive to IM than BCR-ABL-overexpressing cells. BCR-ABL overexpression in turn catalyzed the de novo development of point mutations to a greater extent than chemical mutagenesis. Thus, MMR is characterized by the persistence of CML clones with low BCR-ABL expression that may explain their insensitivity to IM and their low propensity to develop IM resistance through kinase point mutations. These findings may have implications for future treatment strategies of residual disease in CML.
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BCR-ABL mutations in chronic myeloid leukemia.
Hematol. Oncol. Clin. North Am.
PUBLISHED: 11-08-2011
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The advent of imatinib has been a major breakthrough in chronic myeloid leukemia (CML) treatment. A few patients treated with imatinib are either refractory to imatinib or eventually relapse. Resistance is frequently associated with mutations in the kinase domain of BCR-ABL. Over 100 point mutations coding for single amino acid substitutions in the BCR-ABL kinase domain have been isolated from CML patients resistant to imatinib treatment. Most reported mutants are rare, whereas 7 mutated residues comprise two-thirds of all mutations detected. BCR-ABL mutations affect amino acids involved in imatinib binding or in regulatory regions of the BCR-ABL kinase domain, resulting in decreased sensitivity to imatinib while retaining aberrant kinase activity. The early detection of BCR-ABL mutants during therapy may aid in risk stratification as well as molecularly based treatment decisions.
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Impact of additional cytogenetic aberrations at diagnosis on prognosis of CML: long-term observation of 1151 patients from the randomized CML Study IV.
Blood
PUBLISHED: 10-28-2011
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The prognostic relevance of additional cytogenetic findings at diagnosis of chronic myeloid leukemia (CML) is unclear. The impact of additional cytogenetic findings at diagnosis on time to complete cytogenetic (CCR) and major molecular remission (MMR) and progression-free (PFS) and overall survival (OS) was analyzed using data from 1151 Philadelphia chromosome-positive (Ph(+)) CML patients randomized to the German CML Study IV. At diagnosis, 1003 of 1151 patients (87%) had standard t(9;22)(q34;q11) only, 69 patients (6.0%) had variant t(v;22), and 79 (6.9%) additional cytogenetic aberrations (ACAs). Of these, 38 patients (3.3%) lacked the Y chromosome (-Y) and 41 patients (3.6%) had ACAs except -Y; 16 of these (1.4%) were major route (second Philadelphia [Ph] chromosome, trisomy 8, isochromosome 17q, or trisomy 19) and 25 minor route (all other) ACAs. After a median observation time of 5.3 years for patients with t(9;22), t(v;22), -Y, minor- and major-route ACAs, the 5-year PFS was 90%, 81%, 88%, 96%, and 50%, and the 5-year OS was 92%, 87%, 91%, 96%, and 53%, respectively. In patients with major-route ACAs, the times to CCR and MMR were longer and PFS and OS were shorter (P < .001) than in patients with standard t(9;22). We conclude that major-route ACAs at diagnosis are associated with a negative impact on survival and signify progression to the accelerated phase and blast crisis.
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Population pharmacokinetic and exposure-response analysis of nilotinib in patients with newly diagnosed Ph+ chronic myeloid leukemia in chronic phase.
Eur. J. Clin. Pharmacol.
PUBLISHED: 10-19-2011
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We investigated the population pharmacokinetics and exposure-response relationship of nilotinib in patients with newly diagnosed chronic myeloid leukemia (CML) in chronic phase.
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Allogeneic stem cell transplantation for patients harboring T315I BCR-ABL mutated leukemias.
Blood
PUBLISHED: 09-16-2011
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T315I(+) Philadelphia chromosome-positive leukemias are inherently resistant to all licensed tyrosine kinase inhibitors, and therapeutic options remain limited. We report the outcome of allogeneic stem cell transplantation in 64 patients with documented BCR-ABL(T315I) mutations. Median follow-up was 52 months from mutation detection and 26 months from transplantation. At transplantation, 51.5% of patients with chronic myeloid leukemia were in the chronic phase and 4.5% were in advanced phases. Median overall survival after transplantation was 10.3 months (range 5.7 months to not reached [ie, still alive]) for those with chronic myeloid leukemia in the blast phase and 7.4 months (range 1.4 months to not reached [ie, still alive]) for those with Philadelphia chromosome-positive acute lymphoblastic leukemia but has not yet been reached for those in the chronic and accelerated phases of chronic myeloid leukemia. The occurrence of chronic GVHD had a positive impact on overall survival (P = .047). Transplant-related mortality rates were low. Multivariate analysis identified only blast phase at transplantation (hazard ratio 3.68, P = .0011) and unrelated stem cell donor (hazard ratio 2.98, P = .011) as unfavorable factors. We conclude that allogeneic stem cell transplantation represents a valuable therapeutic tool for eligible patients with BCR-ABL(T315I) mutation, a tool that may or may not be replaced by third-generation tyrosine kinase inhibitors.
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BCL6-mediated repression of p53 is critical for leukemia stem cell survival in chronic myeloid leukemia.
J. Exp. Med.
PUBLISHED: 09-12-2011
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Chronic myeloid leukemia (CML) is induced by the oncogenic BCR-ABL1 tyrosine kinase and can be effectively treated for many years with tyrosine kinase inhibitors (TKIs). However, unless CML patients receive life-long TKI treatment, leukemia will eventually recur; this is attributed to the failure of TKI treatment to eradicate leukemia-initiating cells (LICs). Recent work demonstrated that FoxO factors are critical for maintenance of CML-initiating cells; however, the mechanism of FoxO-dependent leukemia initiation remained elusive. Here, we identified the BCL6 protooncogene as a critical effector downstream of FoxO in self-renewal signaling of CML-initiating cells. BCL6 represses Arf and p53 in CML cells and is required for colony formation and initiation of leukemia. Importantly, peptide inhibition of BCL6 in human CML cells compromises colony formation and leukemia initiation in transplant recipients and selectively eradicates CD34(+) CD38(-) LICs in patient-derived CML samples. These findings suggest that pharmacological inhibition of BCL6 may represent a novel strategy to eradicate LICs in CML. Clinical validation of this concept could limit the duration of TKI treatment in CML patients, which is currently life-long, and substantially decrease the risk of blast crisis transformation.
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BCR-ABL transcript dynamics support the hypothesis that leukemic stem cells are reduced during imatinib treatment.
Clin. Cancer Res.
PUBLISHED: 09-08-2011
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Imatinib induces a durable response in most patients with Philadelphia chromosome-positive chronic myeloid leukemia, but it is currently unclear whether imatinib reduces the leukemic stem cell (LSC) burden, which may be an important step toward enabling safe discontinuation of therapy. In this article, we use mathematical models of BCR-ABL levels to make inferences on the dynamics of LSCs.
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Enhanced ABL-inhibitor-induced MAPK-activation in T315I-BCR-ABL-expressing cells: a potential mechanism of altered leukemogenicity.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 09-01-2011
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Targeted treatment of chronic myelogenous leukemia using imatinib has dramatically improved patient outcome. However, residual disease can be detected in the majority of patients treated with imatinib. Compensatory activation of MAP kinases (MAPK1/2) in response to BCR-ABL-inhibitors has been reported as a potential cytokine-dependent resistance mechanism leading to the rescue of leukemic progenitor cells.
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Cancer patients and the Internet: a survey of the Quality of Life Working Groups of the Arbeitsgemeinschaft für Internistische Onkologie and the Nord-Ostdeutsche Gesellschaft für Gynäkologische Onkologie.
Onkologie
PUBLISHED: 08-19-2011
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Patient-reported outcomes, such as quality of life (QoL) assessment, are becoming more important as endpoint in clinical trials and for decision making regarding new anticancer product approvals. Nevertheless, numerous obstacles exist regarding the implementation of QoL assessment in the daily practice of medical oncologists. Regular, computerized or internet home-based QoL assessments could be a step forward.
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Nilotinib versus imatinib for the treatment of patients with newly diagnosed chronic phase, Philadelphia chromosome-positive, chronic myeloid leukaemia: 24-month minimum follow-up of the phase 3 randomised ENESTnd trial.
Lancet Oncol.
PUBLISHED: 08-17-2011
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Nilotinib has shown greater efficacy than imatinib in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukaemia (CML) in chronic phase after a minimum follow-up of 12 months. We present data from the Evaluating Nilotinib Efficacy and Safety in clinical Trials-newly diagnosed patients (ENESTnd) study after a minimum follow-up of 24 months.
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Response of ETV6-FLT3-positive myeloid/lymphoid neoplasm with eosinophilia to inhibitors of FMS-like tyrosine kinase 3.
Blood
PUBLISHED: 06-24-2011
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Imatinib-resistant tyrosine kinase (TK) fusions involving FGFR1, JAK2, or FLT3 are rare but recurrent in patients with eosinophilia-associated neoplasms. We report here 2 male patients with ETV6-FLT3(+) myeloid/lymphoid neoplasms with eosinophilia who were treated with the multitargeted TK inhibitors sunitinib and sorafenib. Patient 1 achieved rapid complete hematologic response and complete cytogenetic response after 3 months of taking sunitinib. A secondary blast phase caused by clonal evolution was diagnosed after 6 months. He achieved a second complete hematologic response after taking sorafenib but relapsed 2 months later. An N841K point mutation within the TK domain of FLT3, previously reported in acute myeloid leukemia and potentially conferring resistance to sorafenib, was subsequently identified. Patient 2 was heavily pretreated according to the initial diagnosis of T-lymphoblastic lymphoma and died in sunitinib-induced pancytopenia. This report highlights the importance of a careful diagnostic workup for eosinophilia-associated neoplasms to evaluate the possibility of TK inhibitor therapy.
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Current treatment concepts of CML.
Curr Cancer Drug Targets
PUBLISHED: 05-19-2011
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The elucidation of the triggering molecular mechanism of chronic myeloid leukemia gave rise to the development of imatinib, a tyrosine kinase inhibitor and a prototype of target-oriented drugs. Imatinib led to impressing response and survival rates and now represents the standard therapy of CML. However, a significant proportion of patients do not tolerate or fail to respond to imatinib treatment. Alternative therapies can be offered to those patients. The particular challenge of CML patient management is to recognize an impending imatinib failure by adequate surveillance and to know about therapeutic options to prevent progression of the disease to accelerated phase or blast crisis since these are more difficult to control. Targeted therapy with second-generation tyrosine kinase inhibitors should be used in synopsis with mutational analysis and the patients history. In this review we present current knowledge of diagnosis, monitoring and therapy strategies of patients with CML.
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BCR-ABL kinase domain mutation analysis in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors: recommendations from an expert panel on behalf of European LeukemiaNet.
Blood
PUBLISHED: 05-11-2011
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Mutations in the Bcr-Abl kinase domain may cause, or contribute to, resistance to tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia patients. Recommendations aimed to rationalize the use of BCR-ABL mutation testing in chronic myeloid leukemia have been compiled by a panel of experts appointed by the European LeukemiaNet (ELN) and European Treatment and Outcome Study and are here reported. Based on a critical review of the literature and, whenever necessary, on panelists experience, key issues were identified and discussed concerning: (1) when to perform mutation analysis, (2) how to perform it, and (3) how to translate results into clinical practice. In chronic phase patients receiving imatinib first-line, mutation analysis is recommended only in case of failure or suboptimal response according to the ELN criteria. In imatinib-resistant patients receiving an alternative TKI, mutation analysis is recommended in case of hematologic or cytogenetic failure as provisionally defined by the ELN. The recommended methodology is direct sequencing, although it may be preceded by screening with other techniques, such as denaturing-high performance liquid chromatography. In all the cases outlined within this abstract, a positive result is an indication for therapeutic change. Some specific mutations weigh on TKI selection.
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Minimal cross-intolerance with nilotinib in patients with chronic myeloid leukemia in chronic or accelerated phase who are intolerant to imatinib.
Blood
PUBLISHED: 04-05-2011
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Nilotinib has significant efficacy in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP) and in patients with CML-CP or CML in accelerated phase (CML-AP) after imatinib failure. We investigated the occurrence of cross-intolerance to nilotinib in imatinib-intolerant patients with CML. Only 1/75 (1%) patients with nonhematologic imatinib intolerance experienced a similar grade 3/4 adverse event (AE), and 3/75 (4%) experienced a similar persistent grade 2 nonhematologic AE on nilotinib. Only 7/40 (18%) patients with hematologic imatinib intolerance discontinued nilotinib, all because of grade 3/4 thrombocytopenia. Ninety percent of imatinib-intolerant patients with CML-CP who did not have complete hematologic response (CHR) at baseline (n = 52) achieved CHR on nilotinib. Nilotinib induced a major cytogenetic response in 66% and 41% of patients with imatinib-intolerant CML-CP and CML-AP (complete cytogenetic response in 51% and 30%), respectively. Minimal cross-intolerance was confirmed in patients with imatinib-intolerant CML. The favorable tolerability of nilotinib in patients with imatinib intolerance leads to alleviation of AE-related symptoms and significant and durable responses. In addition to its established clinical benefit in patients with newly diagnosed CML and those resistant to imatinib, nilotinib is effective and well-tolerated for long-term use in patients with imatinib intolerance. This study is registered at http://www.clinicaltrials.gov as NCT00471497.
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Reconstitution and functional analyses of neutrophils and distinct subsets of monocytes after allogeneic stem cell transplantation.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 03-11-2011
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The aim of the study was to investigate the recovery of the innate immune system within the first 100 days after allogeneic peripheral blood stem cell transplantation (PBSCT) and to elucidate a potential correlation with such important events as severe infectious complications or graft-versus-host disease (GvHD).
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Subclones with the t(9;22)/BCR-ABL1 rearrangement occur in AML and seem to cooperate with distinct genetic alterations.
Br. J. Haematol.
PUBLISHED: 01-31-2011
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In AML, cooperation of mutations suppressing differentiation (class-II-mutations) with class-I-mutations increasing cell proliferation is frequent. In rare cases of myeloid malignancies, the BCR-ABL1 fusion was reported to cooperate as class-I-mutation with class-II-mutations, but most cases had to be classified as blast phase of chronic myeloid leukaemia (CML). We identified five cases of Philadelphia positive subclones in AML occurring in coincidence with other genetic lesions: 1:220 patients with inv(16)/CBFB-MYH11 (0·5%), 2:272 AML cases with t(8;21)/RUNX1-RUNX1T1 (0·7%), 1:1029 NPM1-mutated AML (0·1%), and one patient with s-AML following MDS with a 5q-deletion. Four patients had m-BCR (e1a2) BCR-ABL1 transcripts; one case only had an M-BCR (b3a2) breakpoint. These cases allow some interesting conclusions: The BCR-ABL1 rearrangement apparently can cooperate with the NPM1 mutation similar to other class-I-mutations. The identification of Philadelphia positive subclones in <1% of patients with CBF-leukaemias fits well with previous observations that most CBF-AML are accompanied by activating mutations in genes enhancing proliferation. Since we observed the occurrence of the Philadelphia positive subclones at diagnosis, at relapse, or throughout the disease, the time point of the emergence of Philadelphia subclones seems variable in AML. Clinical research should further concentrate on Philadelphia positive subclones in AML to assess the clinical impact.
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Impact of BCR-ABL mutations on patients with chronic myeloid leukemia.
Cell Cycle
PUBLISHED: 01-15-2011
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Therapies that target BCR-ABL in chronic myeloid leukemia, including imatinib, dasatinib and nilotinib, have dramatically improved patient outcome. BCR-ABL mutations, however, contribute to treatment resistance by disrupting drug contact sites or causing conformational changes thus making contact sites inaccessible. Clinical data indicate that developing BCR-ABL mutations during imatinib treatment is predictive for shorter progression-free survival, and that outcomes may depend on mutation type or location. In vitro, dasatinib and nilotinib inhibit most imatinib-resistant BCR-ABL mutations, except for T315I. In clinical studies, other mutations associated with treatment resistance include V299L, T315A, and F317I/L for dasatinib and Y253F/H, E255K/V, and F359C/V for nilotinib. Evaluating patients with clinical signs of resistance for BCR-ABL mutations is an important component of disease monitoring, potentially facilitating selection of subsequent therapy. First-line treatment with dasatinib or nilotinib instead of imatinib may reduce emergence of resistance but novel agents are needed to overcome the problematic T315I mutation.
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Novel imatinib-sensitive PDGFRA-activating point mutations in hypereosinophilic syndrome induce growth factor independence and leukemia-like disease.
Blood
PUBLISHED: 01-11-2011
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The FIP1L1-PDGFRA fusion is seen in a fraction of cases with a presumptive diagnosis of hypereosinophilic syndrome (HES). However, because most HES patients lack FIP1L1-PDGFRA, we studied whether they harbor activating mutations of the PDGFRA gene. Sequencing of 87 FIP1L1-PDGFRA-negative HES patients revealed several novel PDGFRA point mutations (R481G, L507P, I562M, H570R, H650Q, N659S, L705P, R748G, and Y849S). When cloned into 32D cells, N659S and Y849S and-on selection for high expressors-also H650Q and R748G mutants induced growth factor-independent proliferation, clonogenic growth, and constitutive phosphorylation of PDGFRA and Stat5. Imatinib antagonized Stat5 phosphorylation. Mutations involving positions 659 and 849 had been shown previously to possess transforming potential in gastrointestinal stromal tumors. Because H650Q and R748G mutants possessed only weak transforming activity, we injected 32D cells harboring these mutants or FIP1L1-PDGFRA into mice and found that they induced a leukemia-like disease. Oral imatinib treatment significantly decreased leukemic growth in vivo and prolonged survival. In conclusion, our data provide evidence that imatinib-sensitive PDGFRA point mutations play an important role in the pathogenesis of HES and we propose that more research should be performed to further define the frequency and treatment response of PDGFRA mutations in FIP1L1-PDGFRA-negative HES patients.
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Front-line and salvage therapies with tyrosine kinase inhibitors and other treatments in chronic myeloid leukemia.
J. Clin. Oncol.
PUBLISHED: 01-10-2011
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Chronic myeloid leukemia (CML) has been a model disease in the development of targeted therapies. After nearly 40 years of the recognition of the chromosomal abnormality that defines CML, specific therapy was developed, initially with imatinib mesylate, which has transformed our treatment algorithms and has changed the natural history of the disease. Today, most patients have the expectation of a favorable outcome when treated with standard-dose imatinib. However, a significant proportion of patients do not achieve the optimal desirable outcome. Effective salvage therapy followed the recognition of some of the most common mechanisms of resistance. More recently, the focus has turned to new areas of research and medical need, such as improving the front-line therapy to minimize the risk of resistance, to fight the most resistant mutant forms of BCR-ABL, and to eliminate minimal residual disease with the goal of achieving total elimination of the disease and treatment discontinuation. In this review, we analyze the current status of therapy of CML, and we discuss some of the most relevant clinical questions that we face today.
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Loss or inhibition of stromal-derived PlGF prolongs survival of mice with imatinib-resistant Bcr-Abl1(+) leukemia.
Cancer Cell
PUBLISHED: 01-05-2011
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Imatinib has revolutionized the treatment of Bcr-Abl1(+) chronic myeloid leukemia (CML), but, in most patients, some leukemia cells persist despite continued therapy, while others become resistant. Here, we report that PlGF levels are elevated in CML and that PlGF produced by bone marrow stromal cells (BMSCs) aggravates disease severity. CML cells foster a soil for their own growth by inducing BMSCs to upregulate PlGF, which not only stimulates BM angiogenesis, but also promotes CML proliferation and metabolism, in part independently of Bcr-Abl1 signaling. Anti-PlGF treatment prolongs survival of imatinib-sensitive and -resistant CML mice and adds to the anti-CML activity of imatinib. These results may warrant further investigation of the therapeutic potential of PlGF inhibition for (imatinib-resistant) CML.
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Dynamics of mutant BCR-ABL-positive clones after cessation of tyrosine kinase inhibitor therapy.
Haematologica
PUBLISHED: 12-06-2010
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Point mutations of the BCR-ABL tyrosine kinase domain are considered the predominant cause of imatinib resistance in chronic myeloid leukemia. The expansion of mutant BCR-ABL-positive clones under selective pressure of tyrosine kinase inhibition is referred to as clonal selection; there are few data on the reversibility of this phenomenon.
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Nilotinib is effective in patients with chronic myeloid leukemia in chronic phase after imatinib resistance or intolerance: 24-month follow-up results.
Blood
PUBLISHED: 11-22-2010
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Nilotinib is a potent selective inhibitor of the BCR-ABL tyrosine kinase approved for use in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP), and in CML-CP and CML-accelerated phase after imatinib failure. Nilotinib (400 mg twice daily) was approved on the basis of the initial results of this phase 2 open-label study. The primary study endpoint was the proportion of patients achieving major cytogenetic response (CyR). All patients were followed for ? 24 months or discontinued early. Of 321 patients, 124 (39%) continue on nilotinib treatment. Overall, 59% of patients achieved major CyR; this was complete CyR (CCyR) in 44%. Of patients achieving CCyR, 56% achieved major molecular response. CyRs were durable, with 84% of patients who achieved CCyR maintaining response at 24 months. The overall survival at 24 months was 87%. Adverse events were mostly mild to moderate, generally transient, and easily managed. This study indicates that nilotinib is effective, with a manageable safety profile, and can provide favorable long-term benefits for patients with CML-CP after imatinib failure.
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The European LeukemiaNet: achievements and perspectives.
Haematologica
PUBLISHED: 11-03-2010
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The only way to cure leukemia is by cooperative research. To optimize research, the European LeukemiaNet integrates 105 national leukemia trial groups and networks, 105 interdisciplinary partner groups and about 1,000 leukemia specialists from 175 institutions. They care for tens of thousands of leukemia patients in 33 countries across Europe. Their ultimate goal is to cure leukemia. Since its inception in 2002, the European LeukemiaNet has steadily expanded and has unified leukemia research across Europe. The European LeukemiaNet grew from two major roots: 1) the German Competence Network on Acute and Chronic Leukemias; and 2) the collaboration of European Investigators on Chronic Myeloid Leukemia. The European LeukemiaNet has improved leukemia research and management across Europe. Its concept has led to funding by the European Commission as a network of excellence. Other sources (European Science Foundation; European LeukemiaNet-Foundation) will take over when the support of the European Commission ends.
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Establishment of the first World Health Organization International Genetic Reference Panel for quantitation of BCR-ABL mRNA.
Blood
PUBLISHED: 08-18-2010
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Serial quantitation of BCR-ABL mRNA levels is an important indicator of therapeutic response for patients with chronic myelogenous leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia, but there is substantial variation in the real-time quantitative polymerase chain reaction methodologies used by different testing laboratories. To help improve the comparability of results between centers we sought to develop accredited reference reagents that are directly linked to the BCR-ABL international scale. After assessment of candidate cell lines, a reference material panel comprising 4 different dilution levels of freeze-dried preparations of K562 cells diluted in HL60 cells was prepared. After performance evaluation, the materials were assigned fixed percent BCR-ABL/control gene values according to the International Scale. A recommendation that the 4 materials be established as the first World Health Organization International Genetic Reference Panel for quantitation of BCR-ABL translocation by real-time quantitative polymerase chain reaction was approved by the Expert Committee on Biological Standardization of the World Health Organization in November 2009. We consider that the development of these reagents is a significant milestone in the standardization of this clinically important test, but because they are a limited resource we suggest that their availability is restricted to manufacturers of secondary reference materials.
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An open-label, phase I study of the polo-like kinase-1 inhibitor, BI 2536, in patients with advanced solid tumors.
Clin. Cancer Res.
PUBLISHED: 08-03-2010
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This phase I, open-label, dose-escalation study investigated the maximum tolerated dose (MTD) of BI 2536, a small-molecule polo-like kinase (Plk)-1 inhibitor, in two treatment schedules in patients with advanced solid tumors. Secondary objectives included evaluation of safety, efficacy, and pharmacokinetics.
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Long-term prognostic significance of early molecular response to imatinib in newly diagnosed chronic myeloid leukemia: an analysis from the International Randomized Study of Interferon and STI571 (IRIS).
Blood
PUBLISHED: 08-02-2010
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This study examines the prognostic significance of early molecular response using an expanded dataset in chronic myeloid leukemia patients enrolled in the International Randomized Study of Interferon and STI571 (IRIS). Serial molecular studies demonstrate decreases in BCR-ABL transcripts over time. Analyses of event-free survival (EFS) and time to progression to accelerated phase/blast crisis (AP/BC) at 7 years were based on molecular responses using the international scale (IS) at 6-, 12-, and 18-month landmarks. Patients with BCR-ABL transcripts > 10% at 6 months and > 1% at 12 months had inferior EFS and higher rate of progression to AP/BC compared with all other molecular response groups. Conversely, patients who achieved major molecular response [MMR: BCR-ABL (IS) ? 0.1%] by 18 months enjoyed remarkably durable responses, with no progression to AP/BC and 95% EFS at 7 years. The probability of loss of complete cytogenetic response by 7 years was only 3% for patients in MMR at 18 months versus 26% for patients with complete cytogenetic response but not MMR (P < .001). This study shows a strong association between the degree to which BCR-ABL transcript numbers are reduced by therapy and long-term clinical outcome, supporting the use of time-dependent molecular measures to determine optimal response to therapy. This study is registered at www.clinicaltrials.gov as NCT00006343.
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Annexin and survivin in locally advanced rectal cancer: indicators of resistance to preoperative chemoradiotherapy?
Onkologie
PUBLISHED: 07-22-2010
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Background: The aim of preoperative chemoradiotherapy is improvement of local control in patients with locally advanced rectal cancer (LARC). Recent studies have shown that annexin and survivin are involved in the resistance capability of tumours. We sought to determine whether survivin, annexin A4 or annexin A5 expression predict resistance to preoperative chemoradiotherapy. Material and Methods: Biopsies of tumour and normal rectal tissue were taken from 38 patients with LARC (cT3/4Nx or Tx/N+) before the start of chemoradiotherapy and during surgery. mRNA expression of annexin A4/A5 and survivin was measured by real-time polymerase chain reaction (RT-PCR) and correlated with down-staging and progression-free survival (PFS). Results: Significantly higher mRNA levels of survivin, and annexin A4/A5 were detected in untreated tumour compared with normal mucosa. After chemoradiotherapy, this difference disappeared for survivin and annexin A4. Annexin A5 expression in the tumour increased during chemoradiotherapy. No correlation between the mRNA levels of survivin, annexin A4/A5 and tumour down-staging or PFS was noticed. Conclusions: In the present analysis of 38 patients with LARC undergoing neoadjuvant chemoradiotherapy, the expression levels of survivin and annexin A4 and A5 did not correlate with down-staging. Moreover, with regard to PFS, none of these markers was found to be prognostically relevant.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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