151
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DeAngelo DJ, Attar EC. Use of dasatinib and nilotinib in imatinib-resistant chronic myeloid leukemia: translating preclinical findings to clinical practice. Leuk Lymphoma 2009; 51:363-75. [DOI: 10.3109/10428190903518295] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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152
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Selecting optimal second-line tyrosine kinase inhibitor therapy for chronic myeloid leukemia patients after imatinib failure: does the BCR-ABL mutation status really matter? Blood 2009; 114:5426-35. [PMID: 19880502 DOI: 10.1182/blood-2009-08-215939] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Preclinical studies of BCR-ABL mutation sensitivity to nilotinib or dasatinib suggested that the majority would be sensitive. Correspondingly, the initial clinical trials demonstrated similar response rates for CML patients after imatinib failure, irrespective of the mutation status. However, on closer examination, clinical evidence now indicates that some mutations are less sensitive to nilotinib (Y253H, E255K/V, and F359V/C) or dasatinib (F317L and V299L). T315I is insensitive to both. Novel mutations (F317I/V/C and T315A) are less sensitive/insensitive to dasatinib. We refer to these collectively as second-generation inhibitor (SGI) clinically relevant mutations. By in vitro analysis, other mutations confer a degree of insensitivity; however, clinical evidence is currently insufficient to define them as SGI clinically relevant. Here we examine the mutations that are clearly SGI clinically relevant, those with minimal impact on response, and those for which more data are needed. In our series of patients with mutations at imatinib cessation and/or at nilotinib or dasatinib commencement, 43% had SGI clinically relevant mutations, including 14% with T315I. The frequency of SGI clinically relevant mutations was dependent on the disease phase at imatinib failure. The clinical data suggest that a mutation will often be detectable after imatinib failure for which there is compelling clinical evidence that one SGI should be preferred.
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153
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Kim SH, Kim D, Kim DW, Goh HG, Jang SE, Lee J, Kim WS, Kweon IY, Park SH. Analysis of Bcr-Abl kinase domain mutations in Korean chronic myeloid leukaemia patients: poor clinical outcome of P-loop and T315I mutation is disease phase dependent. Hematol Oncol 2009; 27:190-7. [PMID: 19274615 DOI: 10.1002/hon.894] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Despite durable responses to imatinib in chronic myeloid leukaemia (CML), mutations in Bcr-Abl kinase domain (KD) are known to induce imatinib resistance and cause poor clinical outcome. We characterized Bcr-Abl KD mutations in 137 Korean CML patients with imatinib resistance (n = 111) or intolerance (n = 26) using allele specific oligonucleotide polymerase chain reaction (PCR) and direct sequencing. Seventy (51%) patients harboured 81 mutations of 20 different types with increasing prevalence in advanced phase. Nine (13%) patients had multiple mutations. No mutation was found in intolerant patients. T315I was the most common mutation and P-loop was the hottest spot in Bcr-Abl KD. Patients harbouring P-loop mutation, T315I, or multiple mutations showed poor overall survival and progression free survival compared with patients harbouring other mutations. Survival analysis according to disease phase of mutation being detected and type of mutations provided correlation between P-loop or T315I mutation and poor overall survival in blast crisis, but not in accelerated phase (AP) or chronic phase (CP), indicating poor clinical outcome of particular mutations depends on disease phase. CML patients with imatinib resistance showed high rate (63%) of mutations in Bcr-Abl KD and therefore CML patients who do not respond to imatinib should be the candidates for mutation screening as molecular monitoring.
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Affiliation(s)
- Soo-Hyun Kim
- Molecular Genetics Research Institute, The Catholic University of Korea, Seoul, Korea
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154
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Milojkovic D, Apperley J. Mechanisms of Resistance to Imatinib and Second-Generation Tyrosine Inhibitors in Chronic Myeloid Leukemia. Clin Cancer Res 2009; 15:7519-7527. [PMID: 20008852 DOI: 10.1158/1078-0432.ccr-09-1068] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Targeted therapy in the form of selective tyrosine kinase inhibitors (TKI) has transformed the approach to management of chronic myeloid leukemia (CML) and dramatically improved patient outcome to the extent that imatinib is currently accepted as the first-line agent for nearly all patients presenting with CML, regardless of the phase of the disease. Impressive clinical responses are obtained in the majority of patients in chronic phase; however, not all patients experience an optimal response to imatinib, and furthermore, the clinical response in a number of patients will not be sustained. The process by which the leukemic cells prove resistant to TKIs and the restoration of BCR-ABL1 signal transduction from previous inhibition has initiated the pursuit for the causal mechanisms of resistance and strategies by which to surmount resistance to therapeutic intervention. ABL kinase domain mutations have been extensively implicated in the pathogenesis of TKI resistance, however, it is increasingly evident that the presence of mutations does not explain all cases of resistance and does not account for the failure of TKIs to eliminate minimal residual disease in patients who respond optimally. The focus of exploring TKI resistance has expanded to include the mechanism by which the drug is delivered to its target and the impact of drug influx and efflux proteins on TKI bioavailability. The limitations of imatinib have inspired the development of second generation TKIs in order to overcome the effect of resistance to this primary therapy. (Clin Cancer Res 2009;15(24):7519-27).
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Affiliation(s)
- Dragana Milojkovic
- Authors' Affiliations: Department of Haematology, Hammersmith Hospital, Department of Haematology, Imperial College London, London, United Kingdom
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155
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Stock W. Current treatment options for adult patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Leuk Lymphoma 2009; 51:188-98. [DOI: 10.3109/10428190903452834] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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156
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Hayette S, Chabane K, Tchirkov A, Berger MG, Nicolini FE, Tournilhac O. Detection of twelve nucleotides insertion in the BCR-ABL kinase domain in an imatinib-resistant but dasatinib-sensitive patient with bi-phenotypic acute leukemia. Haematologica 2009; 94:1324-6. [PMID: 19734429 DOI: 10.3324/haematol.2009.007864] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
MESH Headings
- Base Sequence/genetics
- Benzamides
- Dasatinib
- Drug Resistance, Neoplasm
- Female
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Fusion Proteins, bcr-abl/genetics
- Fusion Proteins, bcr-abl/metabolism
- Humans
- Imatinib Mesylate
- Leukemia, Biphenotypic, Acute/drug therapy
- Leukemia, Biphenotypic, Acute/enzymology
- Leukemia, Biphenotypic, Acute/genetics
- Middle Aged
- Piperazines/administration & dosage
- Protein Kinase Inhibitors/administration & dosage
- Protein Structure, Tertiary/genetics
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/genetics
- Protein-Tyrosine Kinases/metabolism
- Pyrimidines/administration & dosage
- Sequence Deletion
- Thiazoles/administration & dosage
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157
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Quintás-Cardama A, Cortés JE. The next generation of therapies for chronic myeloid leukemia. CLINICAL LYMPHOMA & MYELOMA 2009; 9 Suppl 4:S395-403. [PMID: 20007109 DOI: 10.3816/clm.2009.s.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Therapy with the tyrosine kinase inhibitor (TKI) represents the current standard first-line therapy for the management of patients with chronic myeloid leukemia (CML). Although most patients respond satisfactorily to imatinib, a subset of patients develops resistance mainly because of the acquisition of mutations within the kinase domain of BCR-ABL1 that impair the ability of TKIs to block the activity of the enzyme. Moreover, BCR-ABL1 transcripts can be detected in most patients by molecular techniques, underscoring the limitations of imatinib to eradicate minimal residual disease. Although the resistance conferred by most BCR-ABL1 mutations can be overcome with the use of second-generation TKIs such as nilotinib, dasastinib, bosutinib, or bafetinib, the T315I mutation, which represents a common resistance pathway in CML, remains unassailable to TKI therapy. We herein discuss current research efforts in 2 areas of vital importance in CML research, the management of patients with imatinib-resistant mutations, with particular emphasis on those carrying T315I, and the eradication of residual disease.
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Affiliation(s)
- Alfonso Quintás-Cardama
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, 77030, USA
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158
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Santos FPS, Ravandi F. Advances in treatment of chronic myelogenous leukemia--new treatment options with tyrosine kinase inhibitors. Leuk Lymphoma 2009; 50 Suppl 2:16-26. [PMID: 20017607 PMCID: PMC4109296 DOI: 10.3109/10428190903383427] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Imatinib is considered standard therapy for patients with chronic myelogenous leukemia (CML), inducing a high rate of hematologic and cytogenetic responses. Despite these excellent results, several patients develop resistance to imatinib. Mechanisms of resistance are varied and include BCR-ABL1 kinase domain mutations, decreased entry of imatinib into cells, acquisition of secondary genetic changes and activation of alternate signaling pathways. Second-generation tyrosine kinase inhibitors (TKI) (dasatinib, nilotinib) were developed as an alternative for patients that develop resistance or are intolerant to imatinib. Dasatinib is a dual Abl/Src kinase TKI that is structurally unrelated to imatinib and is approved for therapy of all phases of CML in patients who are resistant or intolerant to imatinib. Nilotinib is a compound related to imatinib that has greater specificity and improved binding characteristics, and has clinical activity in the setting of imatinib failure. Resistance to multiple TKIs does occur, particularly in patients with the T315I mutation. Several new agents are in development including new TKIs, aurora kinase inhibitors and homoharringtonine.
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Affiliation(s)
- Fabio P S Santos
- Department of Leukemia, University of Texas - M. D. Anderson Cancer Center, Houston, TX 77030, USA
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159
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Looking Toward the Future: Novel Strategies Based on Molecular Pathogenesis of Acute Lymphoblastic Leukemia. Hematol Oncol Clin North Am 2009; 23:1099-119, vii. [DOI: 10.1016/j.hoc.2009.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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160
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Press RD, Willis SG, Laudadio J, Mauro MJ, Deininger MWN. Determining the rise in BCR-ABL RNA that optimally predicts a kinase domain mutation in patients with chronic myeloid leukemia on imatinib. Blood 2009; 114:2598-605. [PMID: 19625707 PMCID: PMC2756120 DOI: 10.1182/blood-2008-08-173674] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 07/12/2009] [Indexed: 01/02/2023] Open
Abstract
In imatinib-treated chronic myeloid leukemia (CML), secondary drug resistance is often caused by mutations in the BCR-ABL kinase domain (KD). As alternative therapies are available for imatinib resistance, early identification of mutations may prevent disease progression. Because most patients are routinely monitored by BCR-ABL quantitative polymerase chain reaction (PCR), it is important to define the optimal increase in BCR-ABL that should trigger mutation testing. Expert panels have provisionally recommended a 10-fold BCR-ABL increase as the trigger for mutation screening, acknowledging the lack of consensus. To address this question, we monitored 150 CML patients by quantitative PCR and DNA sequencing. Thirty-five different mutations were identified in 53 patients, and, during 22.5 months (median) of follow-up after sequencing, mutations were significantly predictive of shorter progression-free survival. An unbiased receiver operating characteristic analysis identified a 2.6-fold increase in BCR-ABL RNA as the optimal cutoff for predicting a concomitant KD mutation, with a sensitivity of 77% (94% if including subsequent samples). The 2.6-fold threshold approximated the analytic precision limit of our PCR assay. In contrast, transcript rise cutoffs of 5-fold or greater had poor diagnostic sensitivity and no significant association with mutations. We conclude that the currently recommended 10-fold threshold to trigger mutation screening is insensitive and not universally applicable.
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MESH Headings
- Adolescent
- Adult
- Aged
- Antineoplastic Agents/therapeutic use
- Benzamides
- Female
- Fusion Proteins, bcr-abl/analysis
- Fusion Proteins, bcr-abl/chemistry
- Fusion Proteins, bcr-abl/genetics
- Fusion Proteins, bcr-abl/metabolism
- Gene Expression Regulation, Leukemic
- Humans
- Imatinib Mesylate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Male
- Middle Aged
- Mutation/physiology
- Phosphotransferases/chemistry
- Phosphotransferases/genetics
- Piperazines/therapeutic use
- Prognosis
- Protein Structure, Tertiary/genetics
- Pyrimidines/therapeutic use
- RNA, Messenger/analysis
- Retrospective Studies
- Up-Regulation/genetics
- Young Adult
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Affiliation(s)
- Richard D Press
- Department of Pathology, Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97201, USA.
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161
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Philadelphia-positive patients who already harbor imatinib-resistant Bcr-Abl kinase domain mutations have a higher likelihood of developing additional mutations associated with resistance to second- or third-line tyrosine kinase inhibitors. Blood 2009; 114:2168-71. [DOI: 10.1182/blood-2009-01-197186] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Dasatinib and nilotinib are tyrosine kinase inhibitors (TKIs) developed to overcome imatinib resistance in Philadelphia-positive leukemias. To assess how Bcr-Abl kinase domain mutation status evolves during sequential therapy with these TKIs and which mutations may further develop and impair their efficacy, we monitored the mutation status of 95 imatinib-resistant patients before and during treatment with dasatinib and/or nilotinib as second or third TKI. We found that 83% of cases of relapse after an initial response are associated with emergence of newly acquired mutations. However, the spectra of mutants conferring resistance to dasatinib or nilotinib are small and nonoverlapping, except for T315I. Patients already harboring mutations had higher likelihood of relapse associated with development of further mutations compared with patients who did not harbor mutations (23 of 51 vs 8 of 44, respectively, for patients who relapsed on second TKI; 13 of 20 vs 1 of 6, respectively, for patients who relapsed on third TKI).
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162
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Long-term outcome of patients with chronic myeloid leukemia treated with second-generation tyrosine kinase inhibitors after imatinib failure is predicted by the in vitro sensitivity of BCR-ABL kinase domain mutations. Blood 2009; 114:2037-43. [PMID: 19567878 PMCID: PMC4186638 DOI: 10.1182/blood-2009-01-197715] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Secondary imatinib resistance in chronic myeloid leukemia (CML) is associated in approximately 50% of cases with mutations in the BCR-ABL kinase domain, necessitating switch to one of several new tyrosine kinase inhibitors (TKIs) that act differentially on mutated BCR-ABL. We assess here whether scoring mutation based on in vitro inhibitory concentration of each TKI-mutation pair can predict long-term clinical outcome. Among 169 patients with CML after imatinib failure, mutations were detected before TKI switch in 41 (48%) treated with dasatinib and 45 (52%) treated with nilotinib. Inhibitory concentration values for each TKI-mutation pair were stratified into high (n = 42), intermediate (n = 25), low (T315I, n = 9), or unknown sensitivity (n = 10). Hematologic and cytogenetic response rates were similar for patients with or without mutations. For patients in chronic phase, hematologic and cytogenetic responses correlated with mutation score; tumors with low and intermediate scores had lower response rates than those with highly sensitive mutations, and worse event-free and overall survival. These correlations with overall survival were not seen for advanced phases. Mutation scoring can predict outcome in CML-chronic phase with imatinib failure treated with second-generation TKIs and can help in therapy selection. More complex prognostic models will be required for advanced stages of disease.
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163
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Hughes TP, Branford S. Measuring Minimal Residual Disease in Chronic Myeloid Leukemia: Fluorescence In Situ Hybridization and Polymerase Chain Reaction. ACTA ACUST UNITED AC 2009; 9 Suppl 3:S266-71. [DOI: 10.3816/clm.2009.s.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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164
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Clark RE. Facts and uncertainties in monitoring treatment response in chronic myeloid leukaemia. Leuk Res 2009; 33:1151-5. [DOI: 10.1016/j.leukres.2009.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 04/03/2009] [Accepted: 04/04/2009] [Indexed: 11/29/2022]
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165
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Jabbour E, Cortés JE, Kantarjian H. Second-line therapy and beyond resistance for the treatment of patients with chronic myeloid leukemia post imatinib failure. CLINICAL LYMPHOMA & MYELOMA 2009; 9 Suppl 3:S272-9. [PMID: 19778852 DOI: 10.3816/clm.2009.s.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chronic myeloid leukemia (CML) is characterized at the molecular level by the presence of the Philadelphia chromosome (Ph) and the resultant oncogenic signaling by the BCR-ABL fusion protein. The treatment and outlook for CML were revolutionized by the introduction of imatinib, but resistance is a substantial barrier to successful treatment in many patients. Introduction of the second-generation tyrosine kinase inhibitors (TKI) dasatinib and nilotinib has provided effective therapeutic options for many patients with resistance to front-line imatinib. However, the T315I mutation remains a significant clinical issue because it is insensitive to all currently available agents. A number of new agents are in development and many hold the promise of activity in T315I-mutated disease. Successful treatment of patients with disease harboring T315I might lie in the effective combination or sequencing of these new agents with existing TKI therapies.
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Affiliation(s)
- Elias Jabbour
- Department of Leukemia, M. D. Anderson Cancer Center, Houston, TX 77030, USA.
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166
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Abstract
Molecular monitoring in chronic myeloid leukemia (CML) is a powerful tool to document treatment responses and predict relapse. Nonetheless, the proliferation of clinical trials and "guidelines" using the molecular endpoints of CML has outpaced practice norms, commercial laboratory application, and reimbursement practices, leaving some anxiety (if not confusion and despair) about molecular monitoring in the day-to-day treatment of CML. This article will try to address these issues by describing how I monitor CML, which, in summary, is with interest and without panic.
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167
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Du Q, Wang L, Zhu H, Zhang S, Xu L, Zheng W, Liu X. The role of heterogeneous nuclear ribonucleoprotein K in the progression of chronic myeloid leukemia. Med Oncol 2009; 27:673-9. [PMID: 19653139 DOI: 10.1007/s12032-009-9267-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Accepted: 07/03/2009] [Indexed: 10/20/2022]
Abstract
Chronic myeloid leukemia (CML) is a neoplastic disease of the hematopoietic stem cell. Heterogeneous nuclear ribonucleoprotein K (hnRNPK) may up-regulate the transcriptional activity of some oncogenes in cancerous cells. The aim of this study was to verify the expression pattern of hnRNPK in patients with CML, to explore its association with BCR-ABL and some abnormal signaling pathways, and to discover how hnRNPK contributes to the progression of CML. In this study, 15 patients with CML (9 in chronic phase and 6 in blast crisis) were enrolled in this study. The expression of hnRNPK in mononuclear cells (MNCs) from these patients was detected by Western blotting and fluorimeter-based quantitative real-time reverse transcriptase polymerase chain reaction. hnRNPK expression levels in K562 cell line and imatinib-resistant leukemic cell line K562R, following the treatments with the inhibitors of Ras-MAPK (PD98059), PI3K/AKT (LY294002), JAK/STAT (AG490) signaling pathways, and BCR-ABL [imatinib mesylate (IM)], were also determined. As the results, the overexpression of hnRNPK in protein and gene patterns was detected in MNCs from patients with CML comparing with normal donors. Especially, its level in MNCs from patients with CML-blast crisis was significantly higher than in CML-chronic phase cells (P < 0.01). After the treatment with PD98059 (at 4, 8, 24, and 48 h) and IM (at 48 h), the expression levels of hnRNPK in leukemic cell lines were decreased, comparing with DMSO control group (P < 0.05). In conclusion, the results suggest that the overexpression of hnRNPK, which is regulated by BCR-ABL and Ras-MAPK signaling pathways, may promote the progression of CML. hnRNPK would be a potential marker and therapeutic target of CML evolution.
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Affiliation(s)
- Qingfeng Du
- Department of Hematology, Nanfang Hospital, Southern Medical University, 510515, Guangzhou, Guangdong, People's Republic of China
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168
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Hughes T, Saglio G, Branford S, Soverini S, Kim DW, Müller MC, Martinelli G, Cortes J, Beppu L, Gottardi E, Kim D, Erben P, Shou Y, Haque A, Gallagher N, Radich J, Hochhaus A. Impact of baseline BCR-ABL mutations on response to nilotinib in patients with chronic myeloid leukemia in chronic phase. J Clin Oncol 2009; 27:4204-10. [PMID: 19652056 DOI: 10.1200/jco.2009.21.8230] [Citation(s) in RCA: 238] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Nilotinib is a second-generation tyrosine kinase inhibitor indicated for the treatment of patients with chronic myeloid leukemia (CML) in chronic phase (CP; CML-CP) and accelerated phase (AP; CML-AP) who are resistant to or intolerant of prior imatinib therapy. In this subanalysis of a phase II study of nilotinib in patients with imatinib-resistant or imatinib-intolerant CML-CP, the occurrence and impact of baseline and newly detectable BCR-ABL mutations were assessed. PATIENTS AND METHODS Baseline mutation data were assessed in 281 (88%) of 321 patients with CML-CP in the phase II nilotinib registration trial. RESULTS Among imatinib-resistant patients, the frequency of mutations at baseline was 55%. After 12 months of therapy, major cytogenetic response (MCyR) was achieved in 60%, complete cytogenetic response (CCyR) in 40%, and major molecular response (MMR) in 29% of patients without baseline mutations versus 49% (P = .145), 32% (P = .285), and 22% (P = .366), respectively, of patients with mutations. Responses in patients who harbored mutations with high in vitro sensitivity to nilotinib (50% inhibitory concentration [IC(50)] <or= 150 nM) or mutations with unknown nilotinib sensitivity were equivalent to those responses for patients without mutations (not significant). Patients with mutations that were less sensitive to nilotinib in vitro (IC(50) > 150 nM; Y253H, E255V/K, F359V/C) had less favorable responses, as 13%, 43%, and 9% of patients with each of these mutations, respectively, achieved MCyR; none achieved CCyR. CONCLUSION For most patients with imatinib resistance and with mutations, nilotinib offers a substantial probability of response. However, mutational status at baseline may influence response. Less sensitive mutations that occurred at three residues defined in this study, as well as the T315I mutation, may be associated with less favorable responses to nilotinib.
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Affiliation(s)
- Timothy Hughes
- Institute of Medical and Veterinary Science, Hanson Center for Cancer Research, Department of Hematology, Adelaide, 5000, Australia.
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169
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Foroni L, Gerrard G, Nna E, Khorashad JS, Stevens D, Swale B, Milojkovic D, Reid A, Goldman J, Marin D. Technical aspects and clinical applications of measuring BCR-ABL1 transcripts number in chronic myeloid leukemia. Am J Hematol 2009; 84:517-22. [PMID: 19544476 DOI: 10.1002/ajh.21457] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by a triphasic clinical course, the morphologic expansion of a terminally differentiated myeloid cell and the presence of the BCR-ABL1 fusion gene, the hallmark of CML. The fusion gene is usually, but not always, associated with a Philadelphia chromosome, the result of a reciprocal exchange of genetic material between chromosome 22 and chromosome 9, which leads to the production of the activated BCR-ABL1 gene and oncoprotein. The breakpoint in the BCR gene occurs commonly downstream of exons e13 or e14 (M-BCR) and less frequently downstream of exons e1 and e2 (m-BCR). Less than 1% of cases carry a breakpoint downstream of exon 6 or 8 ("variant fusion genes") or exon 19 (mu-BCR). Breakpoints in the ABL1 gene cluster upstream of exon a2 (or of exon a3 in less than 5% of patients with CML). Conventional cytogenetic, fluorescence in situ hybridization, and molecular testing for the BCR-ABL1 fusion gene are key investigations for the diagnosis and monitoring of CML. Treatment using tyrosine kinase inhibitors has revolutionized the management of CML with hematologic and cytogenetic response within 12-18 months observed in >85% of patients. Nevertheless, between 15 and 20% of patients may evolve to blastic phase. Measurement of low level or "minimal" residual disease using molecular tests is becoming the gold-standard approach to measure response to therapy due to its higher sensitivity compared to other routine techniques. The technical aspects and clinical applications of molecular monitoring will be the main focus of this article.
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MESH Headings
- Chromosomes, Human, Pair 22/genetics
- Chromosomes, Human, Pair 22/metabolism
- Chromosomes, Human, Pair 9/genetics
- Chromosomes, Human, Pair 9/metabolism
- Exons/genetics
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Fusion Proteins, bcr-abl/biosynthesis
- Fusion Proteins, bcr-abl/genetics
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Monitoring, Physiologic/methods
- Neoplasm, Residual
- Philadelphia Chromosome
- Protein Kinase Inhibitors/therapeutic use
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- RNA, Neoplasm/biosynthesis
- RNA, Neoplasm/genetics
- Remission Induction
- Time Factors
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Affiliation(s)
- Letizia Foroni
- Department of Haematology, Imperial College Academic Health Science Centre, Hammersmith Campus, London, W12 ONN United Kingdom.
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170
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Baccarani M. New directions in the treatment of patients with chronic myeloid leukemia: introduction. Semin Hematol 2009; 46:S1-4. [PMID: 19621542 DOI: 10.1053/j.seminhematol.2009.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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171
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Quintás-Cardama A, Cortes JE, O'Brien S, Ravandi F, Borthakur G, Liu D, Bleickardt E, Chen TT, Kantarjian HM. Dasatinib early intervention after cytogenetic or hematologic resistance to imatinib in patients with chronic myeloid leukemia. Cancer 2009; 115:2912-21. [PMID: 19402171 DOI: 10.1002/cncr.24325] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Although many patients with chronic myeloid leukemia (CML) respond well to imatinib therapy, a significant proportion loses their initial response. Loss of response on imatinib is often because of BCR-ABL mutations. Dasatinib is a 325-fold more potent inhibitor of Bcr-Abl than imatinib and has been associated with high rates of durable responses in patients with CML in chronic phase (CP) after imatinib failure. METHODS To determine the optimal time for initiating dasatinib after loss of response on imatinib, data from dasatinib trials in CML-CP were analyzed. Patients were grouped according to whether they received early intervention with dasatinib (ie, after cytogenetic recurrence on imatinib), rather than after both cytogenetic and hematologic recurrence. RESULTS Overall, 72% of patients who received dasatinib after loss of a major cytogenetic response (MCyR) on imatinib achieved a complete cytogenetic response (CCyR) compared with 42% of patients who were treated after loss of both MCyR and complete hematologic response (CHR). Event-free survival (EFS) also was higher after earlier dasatinib treatment (24-month EFS rates: 89% after loss of MCyR on imatinib vs 29% after loss of both MCyR and CHR). Among patients who were treated after loss of CHR on imatinib with no prior MCyR, 26% achieved a CCyR with dasatinib, and the 24-month EFS rate was 64%. In all 3 groups, CCyR rates were similar in patients with or without pre-existing BCR-ABL mutations. CONCLUSIONS The results of the current study suggested that optimal outcomes are achieved when dasatinib is administered early after imatinib resistance.
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Affiliation(s)
- Alfonso Quintás-Cardama
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
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Mascarenhas CC, Cunha AF, Miranda EC, Zulli R, Silveira RA, Costa FF, Pagnano KBB, De Souza CA. New mutations detected by denaturing high performance liquid chromatography during screening of exon 6 bcr-abl mutations in patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors. Leuk Lymphoma 2009; 50:1148-54. [PMID: 19557636 DOI: 10.1080/10428190902930496] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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173
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Lipton JH, Khoroshko N, Golenkov A, Abdulkadyrov K, Nair K, Raghunadharao D, Brummendorf T, Yoo K, Bergstrom B. Phase II, randomized, multicenter, comparative study of peginterferon–α–2a (40 kD) (Pegasys®)versusinterferon α-2a (Roferon®-A) in patients with treatment-naïve, chronic-phase chronic myelogenous leukemia. Leuk Lymphoma 2009; 48:497-505. [PMID: 17454589 DOI: 10.1080/10428190601175393] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The efficacy and safety of peginterferon-alpha-2a (40 kD) (PEG-IFNalpha-2a), 450 microg once weekly, versus IFNalpha-2a, 9 MIU once daily, for 12 months, was evaluated in a Phase II study in IFN-naïve patients with chronic-phase, Philadelphia-chromosome-positive CML. At the end of the treatment, complete hematological response was observed in 66.2% (47/71) and 45.2% (33/73) of the PEG-IFNalpha-2a group and IFNalpha-2a groups, respectively (p = 0.009), and major cytogenetic response occurred in 35.2% and 17.8%, respectively (p = 0.016). PEG-IFNalpha-2a was at least as effective as IFNalpha-2a overall, including progression-free survival at the end of treatment, and overall survival after 30 months of follow-up. Adverse events necessitated fewer withdrawals but more dose adjustments in the PEG-IFNalpha-2a group compared with the IFNalpha-2a group (11%versus 23%, and 84.5%versus 65.8%, respectively). In conclusion, PEG-IFNalpha-2a (40 kD), 450 microg once weekly, compared with IFNalpha-2a, 9 MIU once daily, resulted in higher rates of hematologic and cytogenetic response and greater overall survival.
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Affiliation(s)
- Jeffrey H Lipton
- Department of Medical Oncology, Princess Margaret Hospital, Toronto, ON, Canada.
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174
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Class effects of tyrosine kinase inhibitors in the treatment of chronic myeloid leukemia. Leukemia 2009; 23:1698-707. [PMID: 19474800 DOI: 10.1038/leu.2009.111] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tyrosine kinase inhibitors have revolutionized the treatment of chronic myeloid leukemia (CML), offering patients several targeted therapeutic options that provide the possibility of sustained remissions and prolonged survival. With the availability of imatinib, nilotinib and dasatinib, physicians must weigh the efficacy and safety profile of each agent when choosing the best therapeutic option for individual patients. Each agent targets tyrosine kinases within the cell uniquely to cause the desired antiproliferative effect. In addition to inhibiting the BCR-ABL kinase, imatinib and nilotinib target the same array of other tyrosine kinases, including c-KIT and platelet-derived growth factor receptor (PDGFR), albeit with differing potencies. While targeting BCR-ABL with the highest potency among approved agents in CML, dasatinib also targets a broad array of off-target kinases, including SRC family members, PDGFR and EPHB4. The differences in kinase inhibition profiles among these agents in vitro probably account for the differing clinical safety profiles of these agents. This paper reviews the various kinases inhibited by imatinib, nilotinib and dasatinib, and describes the potential impact of kinase inhibition on the efficacy and safety of each agent.
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175
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Abstract
Deregulated BCR-ABL tyrosine kinase (TK) activity is the molecular marker for chronic myeloid leukemia (CML), which provides an identifiable target for developing therapeutic agents. Imatinib mesylate, a BCR-ABL TK inhibitor, is the frontline therapy for CML. Despite the stunning efficacy of this agent, a small number of patients develop a suboptimal response or resistance to imatinib. In newly diagnosed patients with chronic phase CML, the rate of resistance to imatinib at 4 years was up to 20%, increasing to 70% to 90% for patients in the accelerated/blastic phase. Resistance to imatinib led to the development of novel TK inhibitors such as dasatinib. Several clinical trials have reported more durable complete hematologic and cytogenetic responses with this agent in patients who are resistant or intolerant to imatinib. Dasatinib is well tolerated and has broad efficacy, resulting in durable responses in patients with any BCR-ABL mutation except for T3151 and mutations in codon 317 – most commonly F317L – including mutations that were highly resistant to imatinib, such as L248, Y253, E255, F359, and H396. Dasatinib is recommended for CML in chronic, blastic or accelerated phase that is resistant or intolerant to imatinib. Dasatinib was approved by the FDA at 100 mg once daily as the starting dose in patients with chronic phase CML and at 70 mg twice daily in patients with accelerated or blastic phase CML. Various clinical trial results provided evidence that resistance to one TK inhibitor can be reversed with the use of a different TK inhibitor (TKI). Other second-generation TKIs with activity in CML include nilotinib, bosutinib and INNO 406. New molecules, such as the inhibitor of Aurora family serine-threonine kinases, MK0457, which has antileukemic activity in CML associated with a T315I mutation, are being investigated. Allogeneic hematopoietic stem cell transplantation remains an option for selected patients.
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Affiliation(s)
- Dolly G Aguilera
- Department of Hematology-Oncology and Stem Cell Transplantation, Children's Memorial Hospital, Northwestern University, Chicago, IL, USA
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Bellodi C, Lidonnici MR, Hamilton A, Helgason GV, Soliera AR, Ronchetti M, Galavotti S, Young KW, Selmi T, Yacobi R, Van Etten RA, Donato N, Hunter A, Dinsdale D, Tirrò E, Vigneri P, Nicotera P, Dyer MJ, Holyoake T, Salomoni P, Calabretta B. Targeting autophagy potentiates tyrosine kinase inhibitor-induced cell death in Philadelphia chromosome-positive cells, including primary CML stem cells. J Clin Invest 2009; 119:1109-23. [PMID: 19363292 DOI: 10.1172/jci35660] [Citation(s) in RCA: 454] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 02/11/2009] [Indexed: 12/30/2022] Open
Abstract
Imatinib mesylate (IM), a potent inhibitor of the BCR/ABL tyrosine kinase, has become standard first-line therapy for patients with chronic myeloid leukemia (CML), but the frequency of resistance increases in advancing stages of disease. Elimination of BCR/ABL-dependent intracellular signals triggers apoptosis, but it is unclear whether this activates additional cell survival and/or death pathways. We have shown here that IM induces autophagy in CML blast crisis cell lines, CML primary cells, and p210BCR/ABL-expressing myeloid precursor cells. IM-induced autophagy did not involve c-Abl or Bcl-2 activity but was associated with ER stress and was suppressed by depletion of intracellular Ca2+, suggesting it is mechanistically nonoverlapping with IM-induced apoptosis. We further demonstrated that suppression of autophagy using either pharmacological inhibitors or RNA interference of essential autophagy genes enhanced cell death induced by IM in cell lines and primary CML cells. Critically, the combination of a tyrosine kinase inhibitor (TKI), i.e., IM, nilotinib, or dasatinib, with inhibitors of autophagy resulted in near complete elimination of phenotypically and functionally defined CML stem cells. Together, these findings suggest that autophagy inhibitors may enhance the therapeutic effects of TKIs in the treatment of CML.
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177
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Quintás-Cardama A, Kantarjian HM, Cortes JE. Mechanisms of primary and secondary resistance to imatinib in chronic myeloid leukemia. Cancer Control 2009; 16:122-31. [PMID: 19337198 DOI: 10.1177/107327480901600204] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Although the vast majority of patients with chronic myeloid leukemia (CML) respond to the tyrosine kinase inhibitor (TKI) imatinib mesylate, resistance might occur de novo or during treatment. METHODS The authors reviewed the known mechanisms of primary and secondary resistance to imatinib and other TKIs used in the management of CML. RESULTS Mutations within the kinase domain of BCR-ABLI account for 30% to 40% of cases of imatinib resistance. Other mechanisms include BCR-ABLI amplification, overexpression of the SRC family of kinases, and pharmacokinetic and pharmacodynamic factors. CONCLUSIONS Although not all resistance mechanisms have been identified and understood, several agents based on the known mechanisms have already been designed and developed and are beginning clinical trials.
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Affiliation(s)
- Alfonso Quintás-Cardama
- Department of Leukemia at The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
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178
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Verma D, Fava C, Kantarjian H, Cortes J. Complexity of BCR-ABL kinase domain mutations during the course of therapy with tyrosine kinase inhibitors in chronic myeloid leukemia. Am J Hematol 2009; 84:256-7. [PMID: 19260121 DOI: 10.1002/ajh.21366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
MESH Headings
- Aged
- Antineoplastic Agents/pharmacology
- Antineoplastic Agents/therapeutic use
- Antineoplastic Agents, Alkylating/therapeutic use
- Benzamides
- Dasatinib
- Drug Resistance, Neoplasm/genetics
- Female
- Fusion Proteins, bcr-abl/genetics
- Harringtonines/therapeutic use
- Homoharringtonine
- Humans
- Hydroxyurea/therapeutic use
- Imatinib Mesylate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Male
- Middle Aged
- Mutagenesis
- Mutation, Missense
- Piperazines/pharmacology
- Piperazines/therapeutic use
- Point Mutation
- Protein Kinase Inhibitors/pharmacology
- Protein Kinase Inhibitors/therapeutic use
- Protein Structure, Tertiary/genetics
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Thiazoles/pharmacology
- Thiazoles/therapeutic use
- Treatment Failure
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179
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Mauro MJ. Tailoring Tyrosine Kinase Inhibitor Therapy in Chronic Myeloid Leukemia. Cancer Control 2009; 16:108-21. [DOI: 10.1177/107327480901600203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Michael J. Mauro
- Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon
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180
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Jabbour E, Kantarjian HM, Jones D, Shan J, O'Brien S, Reddy N, Wierda WG, Faderl S, Garcia-Manero G, Verstovsek S, Rios MB, Cortes J. Imatinib mesylate dose escalation is associated with durable responses in patients with chronic myeloid leukemia after cytogenetic failure on standard-dose imatinib therapy. Blood 2009; 113:2154-60. [PMID: 19060245 PMCID: PMC4081392 DOI: 10.1182/blood-2008-04-154344] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Accepted: 11/23/2008] [Indexed: 02/03/2023] Open
Abstract
We assessed the long-term efficacy of imatinib dose escalation in 84 patients with chronic myeloid leukemia in chronic phase who met the criteria of failure to standard-dose imatinib. Twenty-one patients with hematologic failure and 63 with cytogenetic failure had their imatinib dose escalated from 400 to 800 mg daily (n = 72) or from 300 to 600 mg daily (n = 12). After a median follow-up of 61 months from dose escalation, 69% remained alive. Complete cytogenetic responses were achieved in 40%; including 52% of patients with cytogenetic failure and 5% of those with hematologic failure. The estimated 2- and 3-year event-free survival and overall survival rates were 57% and 47%, and 84% and 76%, respectively. Responses were long-lasting; 88% of patients with major cytogenetic response sustained their response beyond 2 years. Treatment was well tolerated, with 76% of patients, at 12 months, continuing to receive imatinib at 100% of the intended dose. In conclusion, imatinib dose escalation can induce sustained responses in a subset of patients with cytogenetic failure and a previous cytogenetic response to standard-dose imatinib.
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MESH Headings
- Adolescent
- Adult
- Aged
- Antineoplastic Agents/administration & dosage
- Antineoplastic Agents/adverse effects
- Benzamides
- DNA Mutational Analysis
- Disease-Free Survival
- Female
- Fusion Proteins, bcr-abl/genetics
- Humans
- Imatinib Mesylate
- In Situ Hybridization, Fluorescence
- Kaplan-Meier Estimate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality
- Male
- Middle Aged
- Neoplasm Recurrence, Local/drug therapy
- Neoplasm Recurrence, Local/genetics
- Neoplasm Recurrence, Local/mortality
- Piperazines/administration & dosage
- Piperazines/adverse effects
- Prognosis
- Pyrimidines/administration & dosage
- Pyrimidines/adverse effects
- Reverse Transcriptase Polymerase Chain Reaction
- Treatment Outcome
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Affiliation(s)
- Elias Jabbour
- Department of Leukemia, University of Texas M D Anderson Cancer Center, Houston, TX 77030, USA
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181
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Comparison of imatinib 400 mg and 800 mg daily in the front-line treatment of high-risk, Philadelphia-positive chronic myeloid leukemia: a European LeukemiaNet Study. Blood 2009; 113:4497-504. [PMID: 19264678 DOI: 10.1182/blood-2008-12-191254] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Imatinib mesylate (IM), 400 mg daily, is the standard treatment of Philadelphia-positive (Ph(+)) chronic myeloid leukemia (CML). Preclinical data and results of single-arm studies raised the suggestion that better results could be achieved with a higher dose. To investigate whether the systematic use of a higher dose of IM could lead to better results, 216 patients with Ph(+) CML at high risk (HR) according to the Sokal index were randomly assigned to receive IM 800 mg or 400 mg daily, as front-line therapy, for at least 1 year. The CCgR rate at 1 year was 64% and 58% for the high-dose arm and for the standard-dose arm, respectively (P = .435). No differences were detectable in the CgR at 3 and 6 months, in the molecular response rate at any time, as well as in the rate of other events. Twenty-four (94%) of 25 patients who could tolerate the full 800-mg dose achieved a CCgR, and only 4 (23%) of 17 patients who could tolerate less than 350 mg achieved a CCgR. This study does not support the extensive use of high-dose IM (800 mg daily) front-line in all CML HR patients. This trial was registered at www.clinicaltrials.gov as #NCT00514488.
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182
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Radich JP. Optimizing timing of secondary tyrosine kinase therapy in chronic myeloid leukemia. ACTA ACUST UNITED AC 2009; 8 Suppl 3:S89-94. [PMID: 19254886 DOI: 10.3816/clm.2008.s.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The tyrosine kinase inhibitor (TKI) imatinb has radically changed the treatment of chronic myeloid leukemia (CML). Most patients treated in chronic phase can be expected to achieve a complete cytogenetic remission (CCyR). However, primary imatinib therapy fails in a number of patients initially, or relapse occurs later after a good cytogenetic response. Treatment of accelerated phase and blast crisis yields disappointing results and is rarely associated with long-term disease control. Imatinib failures can now be potentially salvaged with new TKIs or, if a donor exists, by a hematopoetic stem cell transplantation. Given these multiple effective treatment options, tight monitoring of cytogenetic and molecular response is essential in deciding when imatinib therapy should be abandoned for alternative therapy. This review will define the types of tests used to monitor the disease, provide clinically relevant endpoints, and outline guidelines for monitoring patients with CML on imatinib therapy.
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Affiliation(s)
- Jerald P Radich
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
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183
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Abstract
Chronic myeloid leukemia (CML) has been regarded as the paradigmatic example of a malignancy defined by a unique molecular event, the BCR-ABL1 oncogene. Decades of research zeroing in on the role of BCR-ABL1 kinase in the pathogenesis of CML have culminated in the development of highly efficacious therapeutics that, like imatinib mesylate, target the oncogenic kinase activity of BCR-ABL1. In recent years, most research efforts in CML have been devoted to developing novel tyrosine kinase inhibitors (TKIs) as well as to elucidating the mechanisms of resistance to imatinib and other TKIs. Nonetheless, primordial aspects of the pathogenesis of CML, such as the mechanisms responsible for the transition from chronic phase to blast crisis, the causes of genomic instability and faulty DNA repair, the phenomenon of stem cell quiescence, the role of tumor suppressors in TKI resistance and CML progression, or the cross-talk between BCR-ABL1 and other oncogenic signaling pathways, still remain poorly understood. Herein, we synthesize the most relevant and current knowledge on such areas of the pathogenesis of CML.
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184
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Volpe G, Panuzzo C, Ulisciani S, Cilloni D. Imatinib resistance in CML. Cancer Lett 2009; 274:1-9. [DOI: 10.1016/j.canlet.2008.06.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 03/20/2008] [Accepted: 06/02/2008] [Indexed: 12/25/2022]
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185
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Recent advances in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia. Int J Hematol 2008; 89:3-13. [PMID: 19093166 DOI: 10.1007/s12185-008-0223-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 10/01/2008] [Accepted: 11/07/2008] [Indexed: 01/01/2023]
Abstract
The advent of imatinib, a selective inhibitor of the ABL tyrosine kinase, has revolutionized the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Combined with chemotherapy, imatinib exerts remarkable efficacy in patients with newly diagnosed disease with a complete remission (CR) rate of 95% and a survival rate of 55% at 3 years. Profound eradication of leukemia cells not only provides patients with a better chance for receiving allogeneic hematopoietic stem cell transplantation during first CR but also contributes to durable CR even without transplantation. Despite such improvement, however, relapse does occur, mainly owing to acquisition of resistance. Growing comprehension of the molecular mechanisms of resistance to imatinib has led to the development of novel BCR-ABL inhibitors that yield higher affinity for BCR-ABL and/or potent inhibitory activity against other target molecules such as SRC family kinases. The second-generation ABL kinase inhibitors, namely dasatinib and nilotinib, are already showing clinical activity in patients with imatinib-resistant Ph+ ALL, and other novel agents are undergoing preclinical and early clinical evaluation. Further improvement in treatment results will be achieved by identifying each patient's disease profile based on information obtained before and during treatment and by optimizing subsequent treatment accordingly.
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186
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Characteristics and outcome of chronic myeloid leukemia patients with F317L BCR-ABL kinase domain mutation after therapy with tyrosine kinase inhibitors. Blood 2008; 112:4839-42. [PMID: 18818391 PMCID: PMC4186640 DOI: 10.1182/blood-2008-04-149948] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Mutations in codon 317 after treatment with imatinib and dasatinib have been reported. We reviewed patients with chronic myeloid leukemia and mutations after tyrosine kinase inhibitor (TKI) therapy. F317L was detected in 20, including 12/99 (12%) with mutation after imatinib failure, and 8/16 (50%) after dasatinib (P = .001). Median follow-up from mutation detection was 25 months. At the time of F317L, 8 patients were in chronic phase (CP), 6 in accelerated phase, and 6 in blast phase. There was no difference in characteristics between patients with or without F317L mutations, or with no mutations. A complete cytogenetic response was achieved in 3 of 6 patients treated with nilotinib, 2 of 2 with imatinib, and 0 of 3 with dasatinib. Survival of patients with F317L was similar to those with other mutations (P = .45). Patients in CP had better outcome, with a 2-year survival of 75%. F317L mutation is resistant to dasatinib but sensitive to other TKIs. The prognosis is dependent mostly on the disease stage.
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187
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BCR-ABL1-positive CML and BCR-ABL1-negative chronic myeloproliferative disorders: some common and contrasting features. Leukemia 2008; 22:1975-89. [PMID: 19002192 DOI: 10.1038/leu.2008.231] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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188
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Abstract
Chronic myelogenous leukemia (CML) is defined by the presence of the constitutively active tyrosine kinase breakpoint cluster region/Abelson (Bcr-Abl), which activates numerous signal transduction pathways leading to uncontrolled cell proliferation. The development of the Bcr-Abl-targeted imatinib represents a paradigm shift in the treatment of CML, because treatment with imatinib resulted in significantly better patient outcome, response rates, and overall survival compared with previous standards. Despite this advance, not all patients benefit from imatinib because of resistance and intolerance. Resistance to imatinib can develop from a number of mechanisms that can be defined as Bcr-Abl-dependent (e.g., most commonly resulting from point mutations in the Abl kinase domain) and Bcr-Abl-independent mechanisms (including the constitutive activation of downstream signaling molecules, e.g., Src family kinases), which could result in the activation of the pathway regardless of Bcr-Abl inhibition. Clearly, new treatment approaches are required for patients resistant to or intolerant of imatinib, which can be dose escalated in patients who demonstrate resistance. This does not result in long-term responses. Hematopoietic stem cell transplantation is limited by the availability of matched donors and the potential for morbidity. Dasatinib, a dual Bcr-Abl/Src kinase inhibitor, has shown efficacy against all imatinib-resistant Bcr-Abl mutations except for T315I. A large trial program showed that dasatinib is effective in patients previously exposed to imatinib and has a manageable safety profile in all phases of CML and Philadelphia chromosome-positive acute lymphoblastic leukemia, resulting in its approval. Nilotinib, an analogue of imatinib, also has demonstrated activity in a similar patient population. These agents and less clinically advanced strategies are discussed in this review.
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Affiliation(s)
- Pablo Ramirez
- Siteman Cancer Center, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8007, St. Louis, Missouri 63110, USA.
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189
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Khorashad JS, de Lavallade H, Apperley JF, Milojkovic D, Reid AG, Bua M, Szydlo R, Olavarria E, Kaeda J, Goldman JM, Marin D. Finding of kinase domain mutations in patients with chronic phase chronic myeloid leukemia responding to imatinib may identify those at high risk of disease progression. J Clin Oncol 2008; 26:4806-13. [PMID: 18645191 PMCID: PMC10466446 DOI: 10.1200/jco.2008.16.9953] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2008] [Accepted: 05/27/2008] [Indexed: 01/27/2023] Open
Abstract
PURPOSE Kinase domain (KD) mutations in the BCR-ABL gene are associated with resistance to imatinib in chronic myeloid leukemia (CML) but their incidence and prognostic significance in chronic phase (CP) patients without resistance are unclear. PATIENTS AND METHODS We analyzed outcome for 319 patients with CML-CP who were treated with imatinib; 171 were in early CP (ECP) and 148 were in late CP (LCP). Patients were screened routinely for mutations using direct sequencing regardless of response status. The 5-year cumulative incidence of mutations was 6.6% for ECP and 17% for LCP patients. RESULTS Of the 319 patients, 214 (67%) achieved complete cytogenetic responses (CCyR). The identification of a mutation without other evidence of imatinib resistance was highly predictive for loss of CCyR (RR, 3.8; P = .005) and for progression to advanced phase (RR, 2.3; P = .01), though the intervals from first identification to loss of CCyR and disease progression were relatively long (median, 21 and 16 months, respectively). Mutations in the P-loop (excluding residue 244) were associated with a higher risk of progression than mutations elsewhere. CONCLUSION We conclude that routine mutation screening of patients who appear to be responding to imatinib may identify those at high risk of disease progression.
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Affiliation(s)
- Jamshid S. Khorashad
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Hugues de Lavallade
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Jane F. Apperley
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Dragana Milojkovic
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Alistair G. Reid
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Marco Bua
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Richard Szydlo
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Eduardo Olavarria
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - Jaspal Kaeda
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - John M. Goldman
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
| | - David Marin
- From the Department of Haematology, Hammersmith Hospitals Trust, Imperial College London, London, United Kingdom
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Cang S, Liu D. P-loop mutations and novel therapeutic approaches for imatinib failures in chronic myeloid leukemia. J Hematol Oncol 2008; 1:15. [PMID: 18828913 PMCID: PMC2567340 DOI: 10.1186/1756-8722-1-15] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 10/01/2008] [Indexed: 11/10/2022] Open
Abstract
Imatinib was the first BCR-ABL-targeted agent approved for the treatment of patients with chronic myeloid leukemia (CML) and confers significant benefit for most patients; however, a substantial number of patients are either initially refractory or develop resistance. Point mutations within the ABL kinase domain of the BCR-ABL fusion protein are a major underlying cause of resistance. Of the known imatinib-resistant mutations, the most frequently occurring involve the ATP-binding loop (P-loop). In vitro evidence has suggested that these mutations are more oncogenic with respect to other mutations and wild type BCR-ABL. Dasatinib and nilotinib have been approved for second-line treatment of patients with CML who demonstrate resistance (or intolerance) to imatinib. Both agents have marked activity in patients resistant to imatinib; however, they have differential activity against certain mutations, including those of the P-loop. Data from clinical trials suggest that dasatinib may be more effective vs. nilotinib for treating patients harboring P-loop mutations. Other mutations that are differentially sensitive to the second-line tyrosine kinase inhibitors (TKIs) include F317L and F359I/V, which are more sensitive to nilotinib and dasatinib, respectively. P-loop status in patients with CML and the potency of TKIs against P-loop mutations are key determinants for prognosis and response to treatment. This communication reviews the clinical importance of P-loop mutations and the efficacy of the currently available TKIs against them.
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Affiliation(s)
- Shundong Cang
- Division of Hematology/Oncology, New York Medical College, Valhalla, NY 10595, USA.
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191
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Cortes J, Kim DW, Raffoux E, Martinelli G, Ritchie E, Roy L, Coutre S, Corm S, Hamerschlak N, Tang JL, Hochhaus A, Khoury HJ, Brümmendorf TH, Michallet M, Rege-Cambrin G, Gambacorti-Passerini C, Radich JP, Ernst T, Zhu C, Van Tornout JMA, Talpaz M. Efficacy and safety of dasatinib in imatinib-resistant or -intolerant patients with chronic myeloid leukemia in blast phase. Leukemia 2008; 22:2176-83. [DOI: 10.1038/leu.2008.221] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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192
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Abstract
Many of the initial examples of the clinical utility of pharmacogenetics were elucidated in the field of oncology. Those examples were largely based on the existence of germline genetic variation that influences the metabolism of cytotoxic drugs. However, with the development of kinase inhibitors, drugs designed to preferentially target altered proteins driving oncogenesis, pharmacogenetics in cancer has shifted to understanding the somatic differences that determine response to these targeted agents. It is becoming increasingly clear that understanding the molecular genetics of cancer will lead to the further development of targeted therapeutics. Therefore, it is imperative that pharmacogenomics researchers understand the motivations and challenges of developing targeted therapies to treat cancer as a paradigm for personalized medicine. However, much of the discussion in the pharmacogenomics community in cancer is still largely focused on the germline variants as predictors of drug toxicity. In light of that fact, this review presents a detailed discussion of the development of commonly used targeted therapies for the treatment of hematological and solid tumors, the somatic mutations that determine response to those therapies, and the mechanisms of drug resistance.
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193
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Soverini S, Martinelli G, Iacobucci I, Baccarani M. Imatinib mesylate for the treatment of chronic myeloid leukemia. Expert Rev Anticancer Ther 2008; 8:853-64. [PMID: 18533795 DOI: 10.1586/14737140.8.6.853] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chronic myeloid leukemia (CML) is the first human malignancy for which the promise of targeted therapy has come true. CML is invariably associated with a specific genetic lesion--the t(9;22) chromosomal translocation. As a consequence of this translocation, a BCR-ABL fusion gene is formed on the 22q- derivative (traditionally known as the Philadelphia chromosome) and the deregulated tyrosine kinase activity of the protein encoded by this gene has been shown to be both necessary and sufficient for initiation and maintenance of the disease. Imatinib mesylate, an orally available tyrosine kinase inhibitor that targets Bcr-Abl, entered clinical evaluation in 1998. Its efficacy surpassed almost everyone's predictions, and the observation of high response rates and favorable toxicity profile associated with imatinib therapy led to its approval as first-line treatment for all newly diagnosed CML patients over an exceptionally short period of time. The 6-year results of the Phase III trial have recently been reported and confirm durability of responses and declining incidence of adverse events over time, although, at present, occurrence of unexpected side effects in the long term cannot be excluded. Although imatinib does not 'cure' CML and has to be administered chronically to patients, it has revolutionized both outcome and quality of life of CML patients.
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Affiliation(s)
- Simona Soverini
- Department of Hematology & Oncological Sciences "Lorenzo e Ariosto Seràgnoli" University of Bologna, Via Massarenti 9, 40138 Bologna, Italy.
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Abstract
PURPOSE OF REVIEW Despite improvements in the achievement of complete remission and progress in the supportive care of adults with acute lymphoblastic leukemia during the last decade, the majority of patients have eventually relapsed with overall survival in adult acute lymphoblastic leukemia of only 30-40%. However, the recent approach of adapting therapy according to biologic features appears to be resulting in significant progress for specific subsets of adults with acute lymphoblastic leukemia. RECENT FINDINGS The present review highlights some of these new risk-adapted approaches focusing on recent advances in treatment of Philadelphia chromosome positive acute lymphoblastic leukemia and mature B-cell acute lymphoblastic leukemia using biologically targeted therapies, and new approaches to treatment of acute lymphoblastic leukemia in older adolescents and young adults, adopting therapeutic strategies employed in the successful treatment of children with acute lymphoblastic leukemia. A recent study that examines the role of allogeneic stem cell transplant for adults with acute lymphoblastic leukemia in first remission will also be reviewed. SUMMARY The subset-specific approach to therapy of adult acute lymphoblastic leukemia is beginning to result in promising improvements in survival. Future improvements in survival of adults with acute lymphoblastic leukemia will depend on participation in large cooperative group trials using biologically defined protocols for this relatively rare and heterogeneous group of diseases.
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195
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Zinc chelation induces rapid depletion of the X-linked inhibitor of apoptosis and sensitizes prostate cancer cells to TRAIL-mediated apoptosis. Cell Death Differ 2008; 15:1745-51. [PMID: 18617897 DOI: 10.1038/cdd.2008.106] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The X-linked inhibitor of apoptosis (XIAP), the most potent member of the inhibitor of apoptosis protein (IAP) family of endogenous caspase inhibitors, blocks the initiation and execution phases of the apoptotic cascade. As such, XIAP represents an attractive target for treating apoptosis-resistant forms of cancer. Here, we demonstrate that treatment with the membrane-permeable zinc chelator, N,N,N',N',-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) induces a rapid depletion of XIAP at the post-translational level in human PC-3 prostate cancer cells and several non-prostate cell lines. The depletion of XIAP is selective, as TPEN has no effect on the expression of other zinc-binding members of the IAP family, including cIAP1, cIAP2 and survivin. The downregulation of XIAP in TPEN-treated cells occurs via proteasome- and caspase-independent mechanisms and is completely prevented by the serine protease inhibitor, Pefabloc. Finally, our studies demonstrate that TPEN promotes activation of caspases-3 and -9 and sensitizes PC-3 prostate cancer cells to TRAIL-mediated apoptosis. Taken together, our findings indicate that zinc-chelating agents may be used to sensitize malignant cells to established cytotoxic agents via downregulation of XIAP.
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196
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Absolute quantitative detection of ABL tyrosine kinase domain point mutations in chronic myeloid leukemia using a novel nanofluidic platform and mutation-specific PCR. Leukemia 2008; 23:396-9. [PMID: 18615105 DOI: 10.1038/leu.2008.183] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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197
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Walz C, Cross NCP, Van Etten RA, Reiter A. Comparison of mutated ABL1 and JAK2 as oncogenes and drug targets in myeloproliferative disorders. Leukemia 2008; 22:1320-34. [PMID: 18528425 PMCID: PMC3490192 DOI: 10.1038/leu.2008.133] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 04/24/2008] [Accepted: 04/25/2008] [Indexed: 01/17/2023]
Abstract
Constitutively activated mutants of the non-receptor tyrosine kinases (TK) ABL1 (Abelson murine leukemia viral (v-abl) homolog (1) protein) and JAK2 (JAnus Kinase 2 or Just Another Kinase 2) play a central role in the pathogenesis of clinically and morphologically distinct chronic myeloproliferative disorders but are also found in some cases of de novo acute leukemia and lymphoma. Ligand-independent activation occurs as a consequence of point mutations or insertions/deletions within functionally relevant regulatory domains (JAK2) or the creation of TK fusion proteins by balanced reciprocal translocations, insertions or episomal amplification (ABL1 and JAK2). Specific abnormalities are correlated with clinical phenotype, although some are broad and encompass several World Health Organization-defined entities. TKs are excellent drug targets as exemplified by the activity of imatinib in BCR-ABL1-positive disease, particularly chronic myeloid leukemia. Resistance to imatinib is seen in a minority of cases and is often associated with the appearance of secondary point mutations within the TK domain of BCR-ABL1. These mutations are highly variable in their sensitivity to increased doses of imatinib or alternative TK inhibitors such as nilotinib or dasatinib. Selective and non-selective inhibitors of JAK2 are currently being developed, and encouraging data from pre-clinical experiments and initial phase-I studies regarding efficacy and potential toxicity of these compounds have already been reported.
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Affiliation(s)
- Christoph Walz
- Molecular Oncology Research Institute, Tufts Medical Center, Boston, MA, USA
| | - Nicholas C. P. Cross
- Wessex Regional Genetics Laboratory, Salisbury and Human Genetics Division, University of Southampton, U.K
| | | | - Andreas Reiter
- III. Medizinische Universitätsklinik, Medizinische Fakultät Mannheim der Universität Heidelberg, Germany
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198
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Valent P. Emerging stem cell concepts for imatinib-resistant chronic myeloid leukaemia: implications for the biology, management, and therapy of the disease. Br J Haematol 2008; 142:361-78. [PMID: 18540942 DOI: 10.1111/j.1365-2141.2008.07197.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Chronic myeloid leukaemia (CML) is a myeloid neoplasm defined by the BCR/ABL oncoprotein that is considered essential for leukaemogenesis and accumulation of neoplastic cells. The BCR/ABL kinase inhibitor imatinib is an effective agent in most patients and can now be regarded as front-line therapy. Hence, intrinsic and acquired resistance to imatinib has been described and is an emerging challenge in clinical practice. While CML stem cells display primary resistance, stem cell subclones may, in addition, acquire imatinib-resistant mutants of BCR/ABL. Other factors that are considered to contribute to stem cell resistance include the genetic background, clonal evolution, additional biological features of subclones, gene amplifications, silencing of tumour suppressor genes and specific pharmacological aspects. In this article, mechanisms of resistance of CML (stem) cells against imatinib and other BCR/ABL inhibitors are discussed, together with strategies to overcome and/or to prevent resistance with available drugs or novel anti-leukaemic approaches.
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Affiliation(s)
- Peter Valent
- Division of Haematology and Haemostaseology, Department of Internal Medicine I, Medical University of Vienna, Vienna, Austria.
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199
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Loeb LA, Bielas JH, Beckman RA. Cancers Exhibit a Mutator Phenotype: Clinical Implications. Cancer Res 2008; 68:3551-7; discussion 3557. [DOI: 10.1158/0008-5472.can-07-5835] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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200
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Preuner S, Denk D, Frommlet F, Nesslboeck M, Lion T. Quantitative monitoring of cell clones carrying point mutations in the BCR–ABL tyrosine kinase domain by ligation-dependent polymerase chain reaction (LD–PCR). Leukemia 2008; 22:1956-61. [DOI: 10.1038/leu.2008.97] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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