1
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Abaza Y, Kantarjian H, Alwash Y, Borthakur G, Champlin R, Kadia T, Garcia-Manero G, Daver N, Ravandi F, Verstovsek S, Burger J, Estrov Z, Ohanian M, Lim M, Pemmaraju N, Jabbour E, Cortes J. Phase I/II study of dasatinib in combination with decitabine in patients with accelerated or blast phase chronic myeloid leukemia. Am J Hematol 2020; 95:1288-1295. [PMID: 32681739 DOI: 10.1002/ajh.25939] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022]
Abstract
Treatment of advanced-phase chronic myeloid leukemia (CML) remains unsatisfactory. Single-agent tyrosine kinase inhibitors have modest and short-lived activity in this setting. We conducted a phase I/II study to determine safety and efficacy of the combination of dasatinib and decitabine in patients with advanced CML. Two different dose schedules were investigated with a starting decitabine dose of either 10 mg/m2 or 20 mg/m2 daily for 10 days plus dasatinib 100 mg daily. The target dose level was decitabine 10 mg/m2 or 20 mg/m2 daily for 10 days plus dasatinib 140 mg daily. Thirty patients were enrolled, including seven with accelerated-phase CML, 19 with blast-phase CML, and four with Philadelphia-chromosome positive acute myeloid leukemia. No dose-limiting toxicity was observed at the starting dose level with either schedule. Grade ≥3 treatment emergent hematological adverse events were reported in 28 patients. Thirteen patients (48%) achieved a major hematologic response and six (22%) achieved a minor hematologic response, with 44% of these patients achieving a major cytogenetic response and 33% achieving a major molecular response. Median overall survival (OS) was 13.8 months, with significantly higher OS among patients who achieved a hematologic response compared to non-responders (not reached vs 4.65 months; P < .001). Decitabine plus dasatinib is a safe and active regimen in advanced CML. Further studies using this combination are warranted.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Combined Chemotherapy Protocols/administration & dosage
- Antineoplastic Combined Chemotherapy Protocols/adverse effects
- Blast Crisis/blood
- Blast Crisis/drug therapy
- Blast Crisis/mortality
- Dasatinib/administration & dosage
- Dasatinib/adverse effects
- Decitabine/administration & dosage
- Decitabine/adverse effects
- Disease-Free Survival
- Female
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/blood
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality
- Leukemia, Myeloid, Acute/blood
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/mortality
- Male
- Middle Aged
- Survival Rate
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Affiliation(s)
- Yasmin Abaza
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Hagop Kantarjian
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Yasmin Alwash
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gautam Borthakur
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Richard Champlin
- Department of Stem Cell Transplant, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Tapan Kadia
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Naval Daver
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Farhad Ravandi
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Srdan Verstovsek
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jan Burger
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Zeev Estrov
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Maro Ohanian
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Miranda Lim
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Naveen Pemmaraju
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Elias Jabbour
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jorge Cortes
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
- Georgia Cancer Center, Augusta University, Augusta, Georgia
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2
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Kruk M, Widstrom N, Jena S, Wolter NL, Blankenhorn JF, Abdalla I, Yang TY, Parker LL. Assays for tyrosine phosphorylation in human cells. Methods Enzymol 2019; 626:375-406. [PMID: 31606083 DOI: 10.1016/bs.mie.2019.06.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tyrosine kinases are important for many cellular processes and disruption of their regulation is a factor in diseases like cancer, therefore they are a major target of anticancer drugs. There are many ways to measure tyrosine kinase activity in cells by monitoring endogenous substrate phosphorylation, or by using peptide substrates and incubating them with cell lysates containing active kinases. However, most of these strategies rely on antibodies and/or are limited in how accurately they model the intracellular environment. In cases in which activity needs to be measured in cells, but endogenous substrates are not known and/or suitable phosphospecific antibodies are not available, cell-deliverable peptide substrates can be an alternative and can provide information on activation and inhibition of kinases in intact, live cells. In this chapter, we review this methodology and provide a protocol for measuring Abl kinase activity in human cells using enzyme-linked immunosorbent assay (ELISA) with a generic antiphosphotyrosine antibody for detection.
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Affiliation(s)
- Monica Kruk
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Naomi Widstrom
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Sampreeti Jena
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Nicole L Wolter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - John F Blankenhorn
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Ibrahim Abdalla
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Tzu-Yi Yang
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Laurie L Parker
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States.
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3
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César Fassoni A, Roeder I, Glauche I. To Cure or Not to Cure: Consequences of Immunological Interactions in CML Treatment. Bull Math Biol 2019; 81:2345-2395. [DOI: 10.1007/s11538-019-00608-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 04/21/2019] [Indexed: 10/26/2022]
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4
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Shinohara H, Sugito N, Kuranaga Y, Heishima K, Minami Y, Naoe T, Akao Y. Potent antiproliferative effect of fatty-acid derivative AIC-47 on leukemic mice harboring BCR-ABL mutation. Cancer Sci 2019; 110:751-760. [PMID: 30548479 PMCID: PMC6361563 DOI: 10.1111/cas.13913] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/19/2018] [Accepted: 12/01/2018] [Indexed: 12/29/2022] Open
Abstract
Therapy based on targeted inhibition of BCR‐ABL tyrosine kinase has greatly improved the prognosis for patients with Philadelphia chromosome (Ph)‐positive leukemia and tyrosine kinase inhibitors (TKI) have become standard therapy. However, some patients acquire resistance to TKI that is frequently associated with point mutations in BCR‐ABL. We previously reported that a medium‐chain fatty‐acid derivative AIC‐47 induced transcriptional suppression of BCR‐ABL and perturbation of the Warburg effect, leading to growth inhibition in Ph‐positive leukemia cells. Herein, we showed that AIC‐47 had anti‐leukemic effects in either wild type (WT)‐ or mutated‐BCR‐ABL‐harboring cells. AIC‐47 suppressed transcription of BCR‐ABL gene regardless of the mutation through downregulation of transcriptional activator, c‐Myc. Reprogramming of the metabolic pathway has been reported to be associated with resistance to anti‐cancer drugs; however, we found that a point mutation of BCR‐ABL was independent of the profile of pyruvate kinase muscle (PKM) isoform expression. Even in T315I‐mutated cells, AIC‐47 induced switching of the expression profile of PKM isoforms from PKM2 to PKM1, suggesting that AIC‐47 disrupted the Warburg effect. In a leukemic mouse model, AIC‐47 greatly suppressed the increase in BCR‐ABLmRNA level and improved hepatosplenomegaly regardless of the BCR‐ABL mutation. Notably, the improvement of splenomegaly by AIC‐47 was remarkable and might be equal to or greater than that of TKI. These findings suggest that AIC‐47 might be a promising agent for overcoming the resistance of Ph‐positive leukemia to therapy.
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Affiliation(s)
- Haruka Shinohara
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan
| | - Nobuhiko Sugito
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan
| | - Yuki Kuranaga
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan
| | - Kazuki Heishima
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan
| | - Yosuke Minami
- Department of Hematology, National Cancer Center Hospital East, Chiba, Japan.,Department of Transfusion Medicine and Cell Therapy, Kobe University Hospital, Kobe, Japan
| | - Tomoki Naoe
- National Hospital Organization Nagoya Medical Center, Nagoya, Japan
| | - Yukihiro Akao
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan
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5
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Shinohara H, Minami Y, Naoe T, Akao Y. Autophagic degradation determines the fate of T315I-mutated BCR-ABL protein. Haematologica 2018; 104:e191-e194. [PMID: 30467207 DOI: 10.3324/haematol.2018.194431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Haruka Shinohara
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, 1-1 Yanagido
| | - Yosuke Minami
- Department of Hematology, National Cancer Center Hospital East, Chiba.,Department of Transfusion Medicine and Cell Therapy, Kobe University Hospital
| | - Tomoki Naoe
- National Hospital Organization Nagoya Medical Center, Naka-ku, Japan
| | - Yukihiro Akao
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, 1-1 Yanagido
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6
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Fassoni AC, Baldow C, Roeder I, Glauche I. Reduced tyrosine kinase inhibitor dose is predicted to be as effective as standard dose in chronic myeloid leukemia: a simulation study based on phase III trial data. Haematologica 2018; 103:1825-1834. [PMID: 29954936 PMCID: PMC6278983 DOI: 10.3324/haematol.2018.194522] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 06/26/2018] [Indexed: 02/05/2023] Open
Abstract
Continuing tyrosine kinase inhibitor (TKI)-mediated targeting of the BCR-ABL1 oncoprotein is the standard therapy for chronic myeloid leukemia (CML) and allows for a sustained disease control in the majority of patients. While therapy cessation for patients appeared as a safe option for about half of those patients with optimal response, no systematic assessment of long-term TKI dose de-escalation has been made. We use a mathematical model to analyze and consistently describe biphasic treatment responses from TKI-treated patients from two independent clinical phase III trials. Scale estimates reveal that drug efficiency determines the initial response while the long-term behavior is limited by the rare activation of leukemic stem cells. We use this mathematical framework to investigate the influence of different dosing regimens on the treatment outcome. We provide strong evidence to suggest that TKI dose de-escalation (at least 50%) does not lead to a reduction of long-term treatment efficiency for most patients, who have already achieved sustained remission, and maintains the secondary decline of BCR-ABL1 levels. We demonstrate that continuous BCR-ABL1 monitoring provides patient-specific predictions of an optimal reduced dose without decreasing the anti-leukemic effect on residual leukemic stem cells. Our results are consistent with the interim results of the DESTINY trial and provide clinically testable predictions. Our results suggest that dose-halving should be considered as a long-term treatment option for CML patients with good response under continuing maintenance therapy with TKIs. We emphasize the clinical potential of this approach to reduce treatment-related side-effects and treatment costs.
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Affiliation(s)
- Artur C Fassoni
- Instituto de Matemática e Computação, Universidade Federal de Itajubá, Brazil.,Institute for Medical Informatics and Biometry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Christoph Baldow
- Institute for Medical Informatics and Biometry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Ingo Roeder
- Institute for Medical Informatics and Biometry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany
| | - Ingmar Glauche
- Institute for Medical Informatics and Biometry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Germany
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7
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Behzad MM, Shahrabi S, Jaseb K, Bertacchini J, Ketabchi N, Saki N. Aberrant DNA Methylation in Chronic Myeloid Leukemia: Cell Fate Control, Prognosis, and Therapeutic Response. Biochem Genet 2018; 56:149-175. [DOI: 10.1007/s10528-018-9841-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 01/18/2018] [Indexed: 01/24/2023]
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8
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Lang F, Wunderle L, Pfeifer H, Schnittger S, Bug G, Ottmann OG. Dasatinib and Azacitidine Followed by Haploidentical Stem Cell Transplant for Chronic Myeloid Leukemia with Evolving Myelodysplasia: A Case Report and Review of Treatment Options. AMERICAN JOURNAL OF CASE REPORTS 2017; 18:1099-1109. [PMID: 29033451 PMCID: PMC5652250 DOI: 10.12659/ajcr.904956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND CML presenting with a variant Philadelphia translocation, atypical BCR-ABL transcript, additional chromosomal aberrations, and evolving MDS is uncommon and therapeutically challenging. The prognostic significance of these genetic findings is uncertain, even as singular aberrations, with nearly no data on management and outcome when they coexist. MDS evolving during the course of CML may be either treatment-associated or an independently coexisting disease, and is generally considered to have an inferior prognosis. Tyrosine kinase inhibitors (TKI) directed against BCR-ABL are the mainstay of treatment for CML, whereas treatment modalities that may be utilized for MDS and CML include allogeneic stem cell transplant and - at least conceptually - hypomethylating agents. CASE REPORT Here, we describe the clinical course of such a patient, demonstrating that long-term combined treatment with dasatinib and azacitidine for coexisting CML and MDS is feasible and well tolerated, and may be capable of slowing disease progression. This combination therapy had no deleterious effect on subsequent potentially curative haploidentical bone marrow transplantation. CONCLUSIONS The different prognostic implications of this unusual case and new therapeutic options in CML are discussed, together with a review of the current literature on CML presenting with different types of genomic aberrations and the coincident development of MDS. Additionally, this case gives an example of long-term combined treatment of tyrosine kinase inhibitors and hypomethylating agents, which could be pioneering in CML treatment.
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Affiliation(s)
- Fabian Lang
- Department of Hematology/Oncology, Goethe University Hospital, Frankfurt am Main, Germany
| | - Lydia Wunderle
- Department of Hematology/Oncology, Goethe University Hospital, Frankfurt am Main, Germany
| | - Heike Pfeifer
- Department of Hematology/Oncology, Goethe University Hospital, Frankfurt am Main, Germany
| | | | - Gesine Bug
- Department of Hematology/Oncology, Goethe University Hospital, Frankfurt am Main, Germany
| | - Oliver G Ottmann
- Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff, Wales, United Kingdom
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9
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Maiti A, Cortes JE, Brown YD, Kantarjian HM. Phase I/II study of low-dose azacytidine in patients with chronic myeloid leukemia who have minimal residual disease while receiving therapy with tyrosine kinase inhibitors. Leuk Lymphoma 2016; 58:722-725. [PMID: 27658536 DOI: 10.1080/10428194.2016.1207767] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Abhishek Maiti
- a Department of Internal Medicine , The University of Texas Health Science Center at Houston , Houston , TX , USA.,b Department of Leukemia , The University of Texas MD Anderson Cancer Center , Houston , TX , USA
| | - Jorge E Cortes
- b Department of Leukemia , The University of Texas MD Anderson Cancer Center , Houston , TX , USA
| | - Yolanda D Brown
- b Department of Leukemia , The University of Texas MD Anderson Cancer Center , Houston , TX , USA
| | - Hagop M Kantarjian
- b Department of Leukemia , The University of Texas MD Anderson Cancer Center , Houston , TX , USA
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10
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Ko TK, Chin HS, Chuah CT, Huang JW, Ng KP, Khaw SL, Huang DC, Ong ST. The BIM deletion polymorphism: A paradigm of a permissive interaction between germline and acquired TKI resistance factors in chronic myeloid leukemia. Oncotarget 2016; 7:2721-33. [PMID: 26517680 PMCID: PMC4823067 DOI: 10.18632/oncotarget.5436] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/16/2015] [Indexed: 12/23/2022] Open
Abstract
Both germline polymorphisms and tumor-specific genetic alterations can determine the response of a cancer to a given therapy. We previously reported a germline deletion polymorphism in the BIM gene that was sufficient to mediate intrinsic resistance to tyrosine kinase inhibitors (TKI) in chronic myeloid leukemia (CML), as well as other cancers [1]. The deletion polymorphism favored the generation of BIM splice forms lacking the pro-apoptotic BH3 domain, conferring a relative resistance to the TKI imatinib (IM). However, CML patients with the BIM deletion polymorphism developed both partial and complete IM resistance. To understand the mechanisms underlying the latter, we grew CML cells either with or without the BIM deletion polymorphism in increasing IM concentrations. Under these conditions, the BIM deletion polymorphism enhanced the emergence of populations with complete IM resistance, mimicking the situation in patients. Importantly, the combined use of TKIs with the BH3 mimetic ABT-737 overcame the BCR-ABL1-dependent and -independent resistance mechanisms found in these cells. Our results illustrate the interplay between germline and acquired genetic factors in confering TKI resistance, and suggest a therapeutic strategy for patients with complete TKI resistance associated with the BIM deletion polymorphism.
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Affiliation(s)
- Tun Kiat Ko
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore
| | - Hui San Chin
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Charles T.H. Chuah
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore
- Department of Haematology, Singapore General Hospital, Singapore
| | - John W.J. Huang
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore
- Present address: Singapore Institute for Clinical Sciences (SICS), Brenner Centre for Molecular Medicine, Singapore
| | - King-Pan Ng
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore
- Present address: Cancer Science Institute of Singapore, National University of Singapore, Singapore
| | - Seong Lin Khaw
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
- Royal Children's Hospital, Parkville, VIC, Australia
| | - David C.S. Huang
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
- Royal Children's Hospital, Parkville, VIC, Australia
| | - S. Tiong Ong
- Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore
- Department of Haematology, Singapore General Hospital, Singapore
- Department of Medical Oncology, National Cancer Centre, Singapore
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
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11
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Hoareau-Aveilla C, Valentin T, Daugrois C, Quelen C, Mitou G, Quentin S, Jia J, Spicuglia S, Ferrier P, Ceccon M, Giuriato S, Gambacorti-Passerini C, Brousset P, Lamant L, Meggetto F. Reversal of microRNA-150 silencing disadvantages crizotinib-resistant NPM-ALK(+) cell growth. J Clin Invest 2015; 125:3505-18. [PMID: 26258416 DOI: 10.1172/jci78488] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 06/23/2015] [Indexed: 01/20/2023] Open
Abstract
The regulatory microRNA miR-150 is involved in the development of hemopathies and is downregulated in T-lymphomas, such as anaplastic large-cell lymphoma (ALCL) tumors. ALCL is defined by the presence or absence of translocations that activate the anaplastic lymphoma kinase (ALK), with nucleophosmin-ALK (NPM-ALK) fusions being the most common. Here, we compared samples of primary NPM-ALK(+) and NPM-ALK(-) ALCL to investigate the role of miR-150 downstream of NPM-ALK. Methylation of the MIR150 gene was substantially elevated in NPM-ALK(+) biopsies and correlated with reduced miR-150 expression. In NPM-ALK(+) cell lines, DNA hypermethylation-mediated miR-150 repression required ALK-dependent pathways, as ALK inhibition restored miR-150 expression. Moreover, epigenetic silencing of miR-150 was due to the activation of STAT3, a major downstream substrate of NPM-ALK, in cooperation with DNA methyltransferase 1 (DNMT1). Accordingly, miR-150 repression was turned off following treatment with the DNMT inhibitor, decitabine. In murine NPM-ALK(+) xenograft models, miR-150 upregulation induced antineoplastic activity. Treatment of crizotinib-resistant NPM-ALK(+) KARPAS-299-CR06 cells with decitabine or ectopic miR-150 expression reduced viability and growth. Altogether, our results suggest that hypomethylating drugs, alone or in combination with other agents, may benefit ALK(+) patients harboring tumors resistant to crizotinib and other anti-ALK tyrosine kinase inhibitors (TKIs). Moreover, these results support further work on miR-150 in these and other ALK(+) malignancies.
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MESH Headings
- Animals
- Cell Line, Tumor
- Crizotinib
- DNA (Cytosine-5-)-Methyltransferase 1
- DNA (Cytosine-5-)-Methyltransferases/genetics
- DNA (Cytosine-5-)-Methyltransferases/metabolism
- Drug Resistance, Neoplasm
- Female
- Gene Expression Regulation, Neoplastic
- Gene Silencing
- Humans
- Lymphoma, Large-Cell, Anaplastic/drug therapy
- Lymphoma, Large-Cell, Anaplastic/genetics
- Lymphoma, Large-Cell, Anaplastic/metabolism
- Lymphoma, Large-Cell, Anaplastic/pathology
- Male
- Mice
- Mice, Transgenic
- MicroRNAs/biosynthesis
- MicroRNAs/genetics
- Protein-Tyrosine Kinases/genetics
- Protein-Tyrosine Kinases/metabolism
- Pyrazoles/pharmacology
- Pyridines/pharmacology
- RNA, Neoplasm/biosynthesis
- RNA, Neoplasm/genetics
- STAT3 Transcription Factor/genetics
- STAT3 Transcription Factor/metabolism
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12
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Celik S, Akcora D, Ozkan T, Varol N, Aydos S, Sunguroglu A. Methylation analysis of the DAPK1 gene in imatinib-resistant chronic myeloid leukemia patients. Oncol Lett 2014; 9:399-404. [PMID: 25435999 PMCID: PMC4246661 DOI: 10.3892/ol.2014.2677] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Accepted: 10/20/2014] [Indexed: 12/16/2022] Open
Abstract
Death-associated protein kinase-1 (DAPK1) is a pro-apoptotic gene that induces cellular apoptosis in response to internal and external apoptotic stimulants. The silencing of DAPK1 can result in uncontrolled cell proliferation, indicating that it may have a role in tumor suppression. DAPK1 activity can be inhibited by the cytosine methylation that occurs in its promoter region. These methylation changes in the promoter region of DAPK1 have been reported in a range of solid and hematological malignancies. In the present study, DAPK1 methylation was investigated in chronic myeloid leukemia patients (n=43) using bisulfite conversion followed by methylation-specific polymerase chain reaction. The present study included a number of patients who were identified to be resistant to the common chemotherapeutic agent imatinib (STI571, Gleevec®, Glivec®), exhibiting at least one mutation in the breakpoint cluster region-Abelson murine leukemia (BCR-ABL) gene. Thus, the patients in the present study were divided into two groups according to their response to imatinib therapy: Non-resistant (n=26) and resistant (n=17) to imatinib. Resistant patients were characterized by the presence of single or multiple mutations of the BCR-ABL gene: i) T315I, ii) M351T, iii) E255K, iv) T315I and M351T or v) T315I, M351T and E255K. The present study identified that: i) The incidence of DAPK1 methylation was significantly higher in the resistant patients compared with the non-resistant patients; ii) the extent of resistance varied between mutation types; and iii) there was no DAPK1 methylation in any of the healthy controls. These findings indicate that DAPK1 methylation may be associated with a signaling pathway for imatinib resistance in chronic myeloid leukemia.
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Affiliation(s)
- Selcen Celik
- Department of Basic Biotechnology, Institute of Biotechnology, Ankara University, Golbasi, Ankara 06830, Turkey
| | - Dilara Akcora
- Department of Medical Biology, Faculty of Medicine, Ankara University, Sihhiye, Ankara 06100, Turkey ; Department of Biology, Faculty of Arts and Sciences, Mehmet Akif Ersoy University, Burdur 15100, Turkey
| | - Tulin Ozkan
- Department of Basic Biotechnology, Institute of Biotechnology, Ankara University, Golbasi, Ankara 06830, Turkey
| | - Nuray Varol
- Department of Medical Biology, Faculty of Medicine, Ankara University, Sihhiye, Ankara 06100, Turkey
| | - Sena Aydos
- Department of Medical Biology, Faculty of Medicine, Ankara University, Sihhiye, Ankara 06100, Turkey
| | - Asuman Sunguroglu
- Department of Medical Biology, Faculty of Medicine, Ankara University, Sihhiye, Ankara 06100, Turkey
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13
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Luo X, Feng M, Zhu X, Li Y, Fei J, Zhang Y. VEGF depletion enhances bcr-abl-specific sensitivity of arsenic trioxide in chronic myelogenous leukemia. ACTA ACUST UNITED AC 2014; 18:334-40. [PMID: 24129092 DOI: 10.1179/1607845413y.0000000083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The development of resistance to imatinib mesylate may partly depend on high bcr-abl expression levels or point mutation(s). Arsenic trioxide (ATO) has bcr-abl suppressing activity in vitro, without cross-resistance to imatinib. Meanwhile, bcr-abl also induces expression of vascular endothelial growth factor (VEGF), which is associated with tumor-related angiogenesis and is involved in chronic myelogenous leukemia (CML) pathogenesis. Here, we investigated ways to improve ATO activity in CML by modulating cellular VEGF levels. K562 and primary CML cells were transfected with a VEGF antisense sequence. Cell viability and survival were assessed using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide and trypan blue exclusion assays. Apoptotic cells were detected by flow cytometry following annexin V and propidium iodide staining. The results showed that VEGF depletion effectively promotes enhanced ATO antileukemic activity by repressing bcr-abl protein levels. These data provide a rationale for the clinical development of optimized ATO-based regimens that incorporate VEGF modulator for CML treatment.
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Xu HB, Xu LZ, Mao XP, Fu J. Guggulsterone of Commiphora mukul resin reverses drug resistance in imatinib-resistant leukemic cells by inhibiting cyclooxygenase-2 and P-glycoprotein. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:1004-1009. [PMID: 24680616 DOI: 10.1016/j.phymed.2014.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 01/09/2014] [Accepted: 02/24/2014] [Indexed: 06/03/2023]
Abstract
The purpose of this study was to investigate the effects of guggulsterone on cyclooxygenase-2 and P-glycoprotein mediated drug resistance in imatinib-resistant K562 cells (K562/IMA). MTT cytotoxicity assay, flow cytometry, western blot analysis, and ELISA were performed to investigate the anti-proliferative effect, the reversal action of drug resistance, and the inhibitory effect on cyclooxygenase-2, P-glycoprotein, BCR/ABL kinase, and PGE2 release in K562/IMA cells by guggulsterone. The results showed that co-administration of guggulsterone resulted in a significant increase in chemo-sensitivity of K562/IMA cells to imatinib, compared with imatinib treatment alone. Rhodamine123 accumulation in K562/IMA cells was significantly enhanced after incubation with guggulsterone (60, 120 μM), compared with untreated K562/IMA cells (p<0.05). When imatinib (1 μM) was combined with guggulsterone (60, 120 μM), the mean apoptotic population of K562/IMA cells was 15.47% and 24.91%. It was increased by 3.82 and 6.79 times, compared with imatinib (1 μM) treatment alone. Furthermore, guggulsterone had significantly inhibitory effects on the levels of cyclooxygenase-2, P-glycoprotein and prostaglandin E2. However, guggulsterone had little inhibitory effect on the activity of BCR/ABL kinase. The present study indicates guggulsterone induces apoptosis by inhibiting cyclooxygenase-2 and down-regulating P-glycoprotein expression in K562/IMA cells.
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Affiliation(s)
- Hong-Bin Xu
- Department of Clinical Pharmacy, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.
| | - Lu-Zhong Xu
- Department of Clinical Pharmacy, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
| | - Xia-Ping Mao
- Department of Clinical Pharmacy, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
| | - Jun Fu
- Department of Clinical Pharmacy, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
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15
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Wnt5a enhances the response of CML cells to Imatinib Mesylate through JNK activation and γ-catenin inhibition. Leuk Res 2013; 37:1532-7. [DOI: 10.1016/j.leukres.2013.07.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 07/12/2013] [Indexed: 11/20/2022]
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16
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Huang S, Leung VYL, Long D, Chan D, Lu WW, Cheung KMC, Zhou G. Coupling of small leucine-rich proteoglycans to hypoxic survival of a progenitor cell-like subpopulation in Rhesus Macaque intervertebral disc. Biomaterials 2013; 34:6548-58. [PMID: 23764115 DOI: 10.1016/j.biomaterials.2013.05.027] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 05/16/2013] [Indexed: 01/07/2023]
Abstract
Degeneration of the intervertebral disc (IVD) is a major spinal disorder that associates with neck and back pain. Recent studies of clinical samples and animal models for IVD degeneration have identified cells with multi-potency in the IVD. However, IVD tissue-specific progenitor cells and their niche components are not clear, although degenerated IVD-derived cells possess in vitro characteristics of mesenchymal stromal cell (MSCs). Here, we firstly identified the tissue-specific intervertebral disc progenitor cells (DPCs) from healthy Rhesus monkey and report the niche components modulated the survival of DPCs under hypoxia. DPCs possess clonogenicity, multipotency and retain differentiation potential after extended expansion in vitro and in vivo. In particular, the nucleus pulposus-derived DPCs are sensitive to low oxygen tension and undergo apoptosis under hypoxic conditions due to their inability to induce/stabilize hypoxia-inducible factors (HIF). The presence of small leucine-rich proteoglycans (SLRP), biglycan or decorin, can reduce the susceptibility of DPCs to hypoxia-induced apoptosis via promoting the activation/stabilization of HIF-1α and HIF-2α. As IVD is avascular, we propose SLRPs are niche components of DPCs in IVD homeostasis, providing new insights in progenitor cell biology and niche factors under a hypoxic microenvironment.
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Affiliation(s)
- Shishu Huang
- Department of Orthopaedics and Traumatology, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administrative Region
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17
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Stella S, Tirrò E, Conte E, Stagno F, Di Raimondo F, Manzella L, Vigneri P. Suppression of survivin induced by a BCR-ABL/JAK2/STAT3 pathway sensitizes imatinib-resistant CML cells to different cytotoxic drugs. Mol Cancer Ther 2013; 12:1085-98. [PMID: 23536723 DOI: 10.1158/1535-7163.mct-12-0550] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The BCR-ABL oncoprotein of chronic myelogenous leukemia (CML) displays exclusive cytoplasmic localization and constitutive tyrosine kinase activity leading to the activation of different pathways that favor cell proliferation and survival. BCR-ABL induces survivin expression at both the mRNA and protein level, thus inhibiting the apoptotic machinery of CML cells and contributing to the expansion of the leukemic clone. We report that, in human CML cell lines, BCR-ABL-mediated upregulation of survivin involves the JAK2/STAT3 pathway since silencing of either protein caused a consistent reduction in survivin expression. Cell lines unresponsive to imatinib mesylate (IM) because of BCR-ABL gene amplification were not resensitized to the drug after survivin downregulation. However, cells insensitive to IM because of point mutations in the BCR-ABL kinase domain were highly responsive to hydroxyurea (HU) after survivin silencing. To address the possible clinical applications of our results, we used shepherdin, a cell-permeable peptidomimetic compound that downregulates survivin expression by preventing its interaction with Hsp90. Incubation with shepherdin of immortalized cell lines both sensitive and resistant to IM enhanced cell death induced by HU and doxorubicin. Similarly, the combination of shepherdin with first- and second-generation tyrosine kinase inhibitors reduced the colony-forming potential of human progenitors derived from both patients with IM-sensitive and IM-resistant CML. These results suggest that strategies aimed at reducing survivin levels may represent a potential therapeutic option for patients with CML unresponsive to IM.
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Affiliation(s)
- Stefania Stella
- Department of Clinical and Molecular Bio-Medicine, University of Catania, Catania, Italy
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18
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Meng F, Sun G, Zhong M, Yu Y, Brewer MA. Anticancer efficacy of cisplatin and trichostatin A or 5-aza-2'-deoxycytidine on ovarian cancer. Br J Cancer 2013; 108:579-86. [PMID: 23370212 PMCID: PMC3593556 DOI: 10.1038/bjc.2013.10] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND To evaluate the anticancer efficacy of the combination of epigenetic modifiers and cisplatin in human ovarian cancer. METHODS The effect of trichostatin A (TSA) and 5-aza-2'-deoxycytidine alone or in combination with low-dose cisplatin was evaluated on human ovarian cancer cell lines in vitro. We measured drug interaction by MTS assay, migration by transwell assay, expression of epithelial to mesenchymal transition (EMT) markers (Twist, Snail, Slug, E-cadherin, and N-cadherin), pluripotency markers (Oct4, Sox2, and Nanog), and epigenetic markers (DNMT3A, LSD1 and H3K4me2, H3K4me3, H3K9me2, and H3K9me3) by western blot, and the impact on and characteristics of spheroid growth when exposed to these drugs. Mouse xenografts were used to evaluate the anticancer effect of sequential drug treatment. RESULTS Combination treatment had greater efficacy than single drugs and significantly suppressed cell viability, migration, and spheroid formation and growth. Sequential treatment of cisplatin (1 mg kg(-1)) followed by TSA (0.3 mg kg(-1)) significantly suppressed tumorigenicity of HEY xenografts through inhibition of EMT and decreased pluripotency of ovarian cancer cells. CONCLUSION Epigenetic modifiers potentiate the anticancer efficacy of low-dose cisplatin in ovarian cancer through regulation of EMT and pluripotency, and may provide a promising treatment for ovarian cancer patients.
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Affiliation(s)
- F Meng
- Division of Gynecologic Oncology, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA
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19
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Inhibition of small GTPase RalA regulates growth and arsenic-induced apoptosis in chronic myeloid leukemia (CML) cells. Cell Signal 2012; 24:1134-40. [DOI: 10.1016/j.cellsig.2012.01.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 01/27/2012] [Accepted: 01/27/2012] [Indexed: 11/20/2022]
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20
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Chandramohan Reddy T, Bharat Reddy D, Aparna A, Arunasree KM, Gupta G, Achari C, Reddy G, Lakshmipathi V, Subramanyam A, Reddanna P. Anti-leukemic effects of gallic acid on human leukemia K562 cells: Downregulation of COX-2, inhibition of BCR/ABL kinase and NF-κB inactivation. Toxicol In Vitro 2012; 26:396-405. [DOI: 10.1016/j.tiv.2011.12.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 12/04/2011] [Accepted: 12/27/2011] [Indexed: 12/21/2022]
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21
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Härtel N, Klag T, Hanfstein B, Mueller MC, Schenk T, Erben P, Hochhaus A, La Rosée P. Enhanced ABL-inhibitor-induced MAPK-activation in T315I-BCR-ABL-expressing cells: a potential mechanism of altered leukemogenicity. J Cancer Res Clin Oncol 2011; 138:203-12. [DOI: 10.1007/s00432-011-1086-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 11/01/2011] [Indexed: 10/15/2022]
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22
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Altman JK, Sassano A, Kaur S, Glaser H, Kroczynska B, Redig AJ, Russo S, Barr S, Platanias LC. Dual mTORC2/mTORC1 targeting results in potent suppressive effects on acute myeloid leukemia (AML) progenitors. Clin Cancer Res 2011; 17:4378-88. [PMID: 21415215 DOI: 10.1158/1078-0432.ccr-10-2285] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
PURPOSE To determine whether mTORC2 and rapamycin-insensitive (RI)-mTORC1 complexes are present in acute myeloid leukemia (AML) cells and to examine the effects of dual mTORC2/mTORC1 inhibition on primitive AML leukemic progenitors. EXPERIMENTAL DESIGN Combinations of different experimental approaches were used, including immunoblotting to detect phosphorylated/activated forms of elements of the mTOR pathway in leukemic cell lines and primary AML blasts; cell-proliferation assays; direct assessment of mRNA translation in polysomal fractions of leukemic cells; and clonogenic assays in methylcellulose to evaluate leukemic progenitor-colony formation. RESULTS mTORC2 complexes are active in AML cells and play critical roles in leukemogenesis. RI-mTORC1 complexes are also formed and regulate the activity of the translational repressor 4E-BP1 in AML cells. OSI-027 blocks mTORC1 and mTORC2 activities and suppresses mRNA translation of cyclin D1 and other genes that mediate proliferative responses in AML cells. Moreover, OSI-027 acts as a potent suppressor of primitive leukemic precursors from AML patients and is much more effective than rapamycin in eliciting antileukemic effects in vitro. CONCLUSIONS Dual targeting of mTORC2 and mTORC1 results in potent suppressive effects on primitive leukemic progenitors from AML patients. Inhibition of the mTOR catalytic site with OSI-027 results in suppression of both mTORC2 and RI-mTORC1 complexes and elicits much more potent antileukemic responses than selective mTORC1 targeting with rapamycin.
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Affiliation(s)
- Jessica K Altman
- Robert H. Lurie Comprehensive Cancer Center and Division of Hematology/Oncology, Northwestern University Medical School and Jesse Brown VA Medical Center, Chicago, Illinois, USA
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23
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Quintás-Cardama A, Kantarjian H, Garcia-Manero G, O'Brien S, Faderl S, Ravandi F, Giles F, Thomas D, Wierda W, Cortes J. A pilot study of imatinib, low-dose cytarabine and idarubicin for patients with chronic myeloid leukemia in myeloid blast phase. Leuk Lymphoma 2009; 48:283-9. [PMID: 17325887 DOI: 10.1080/10428190601075973] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Imatinib is the single most effective agent in chronic myelogenous leukemia (CML) in blast phase (BP), inducing hematologic responses in 30 - 50% of patients. However, only a few of these are complete (CHR) and durable. Imatinib is synergistic with idarubicin and cytarabine. We administered imatinib 600 mg/day, cytarabine 10 mg/day subcutaneous, and idarubicin 12 mg/m2 intravenous every 14 days in 19 patients with CML in myeloid BP. Fourteen patients (74%) achieved a hematologic response: CHR in 9 (47%) (3 with complete and 1 with minor cytogenetic responses) and return to chronic phase (RTC) in 5 (26%). Median duration of response was 10 weeks (range, 2 - 89). Six patients received allogeneic stem cell transplantation: 4 CHR, 1 chronic phase and 1 BP. Median survival was 5 months (range, 2 - 20 months). This outpatient regimen is effective and well tolerated and perhaps superior to single-agent imatinib for patients in myeloid BP.
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Affiliation(s)
- Alfonso Quintás-Cardama
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center. Houston, TX 77030, USA
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24
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Affiliation(s)
- Carla Kurkjian
- Advanced Developmental Therapeutics Training Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, Maryland, USA
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25
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Carney DA. Arsenic trioxide mechanisms of action--looking beyond acute promyelocytic leukemia. Leuk Lymphoma 2008; 49:1846-51. [PMID: 18949607 DOI: 10.1080/10428190802464745] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Dennis A Carney
- Department of Hematology and Medical Oncology, Peter MacCallum Cancer Centre, East Melbourne, VIC, Australia.
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26
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Imatinib-resistant K562 cells are more sensitive to celecoxib, a selective COX-2 inhibitor: role of COX-2 and MDR-1. Leuk Res 2008; 32:855-64. [PMID: 18083230 DOI: 10.1016/j.leukres.2007.11.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 09/17/2007] [Accepted: 11/05/2007] [Indexed: 12/21/2022]
Abstract
Selective inhibition of the BCR/ABL tyrosine kinase by imatinib (STI571, Glivec/Gleevec) is the therapeutic strategy in patients with chronic myelogenous leukemia (CML). Despite significant hematologic and cytogenetic responses with imatinib, mainly due to the mutations in the Abl kinase domain, resistance occurs in patients with advanced disease. In the present study on imatinib-resistant K562 cells (IR-K562), however, no such mutations in the Abl kinase domain were observed. Further studies revealed the over-expression of COX-2 and MDR-1 in IR-K562 cells suggesting the possible involvement of COX-2 in the development of resistance to imatinib. So, we sought to examine the effect of celecoxib, a selective COX-2 inhibitor, on IR-K562 cells. The results clearly indicate that celecoxib is more effective in IR-K562 cells with a lower IC50 value of 10 microM compared to an IC50 value of 40 microM in K562 cells. This increase in the sensitivity of IR-K562 cells towards celecoxib suggests that the development of resistance in IR-K562 cells is COX-2 dependent. Further studies revealed down-regulation of MDR-1 by celecoxib and a decline in p-Akt levels. Celecoxib-induced apoptosis of IR-K562 cells led to release of cytochrome c, PARP cleavage and decreased Bcl2/Bax ratio. Also, celecoxib at 1 microM concentration induced apoptosis in IR-K562 cells synergistically with imatinib by reducing the IC50 value of imatinib from 10 to 6 microM. In conclusion, the present study indicates over-expression of COX-2 and MDR-1 in IR-K562 cells and celecoxib, a COX-2 specific inhibitor, induces apoptosis by inhibiting COX-2 and down-regulating MDR-1 expression through Akt/p-Akt signaling pathway.
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27
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Giles FJ, DeAngelo DJ, Baccarani M, Deininger M, Guilhot F, Hughes T, Mauro M, Radich J, Ottmann O, Cortes J. Optimizing Outcomes for Patients With Advanced Disease in Chronic Myelogenous Leukemia. Semin Oncol 2008; 35:S1-17; quiz S18-20. [DOI: 10.1053/j.seminoncol.2007.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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28
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Melo JV, Chuah C. Novel agents in CML therapy: tyrosine kinase inhibitors and beyond. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2008; 2008:427-435. [PMID: 19074121 DOI: 10.1182/asheducation-2008.1.427] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The emergence of resistance to imatinib has become a significant problem despite the remarkable clinical results achieved with this tyrosine kinase inhibitor in the treatment of chronic myeloid leukaemia. The most common cause of imatinib resistance is the selection of leukemic clones with point mutations in the Abl kinase domain. These mutations lead to amino acid substitutions and prevent the appropriate binding of imatinib. Genomic amplification of BCR-ABL, modulation of drug efflux or influx transporters, and Bcr-Abl-independent mechanisms also play important roles in the development of resistance. Persistent disease is another therapeutic challenge and may in part, be due to the inability of imatinib to eradicate primitive stem cell progenitors. A multitude of novel agents have been developed and have shown in vitro and in vivo efficacy in overcoming imatinib resistance. In this review, we will discuss the current status of the ATP-competitive and non-ATP-competitive Bcr-Abl tyrosine kinase inhibitors. We will also describe inhibitors acting on targets found in signaling pathways downstream of Bcr-Abl, such as the Ras-Raf-mitogen-activated protein kinase and phosphatidylinositol-3 kinase-Akt-mammalian target of rapamycin pathways, and targets without established links with Bcr-Abl.
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Affiliation(s)
- Junia V Melo
- Division of Haematology, Institute of Medical & Veterinary Science, Adelaide SA, Australia.
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29
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Thomas EK, Cancelas JA, Chae HD, Cox AD, Keller PJ, Perrotti D, Neviani P, Druker BJ, Setchell KDR, Zheng Y, Harris CE, Williams DA. Rac guanosine triphosphatases represent integrating molecular therapeutic targets for BCR-ABL-induced myeloproliferative disease. Cancer Cell 2007; 12:467-78. [PMID: 17996650 DOI: 10.1016/j.ccr.2007.10.015] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 06/07/2007] [Accepted: 10/10/2007] [Indexed: 12/16/2022]
Abstract
Chronic myelogenous leukemia (CML) is a clonal myeloproliferative disease (MPD) initiated by expression of the p210-BCR-ABL fusion protein. We demonstrate in a murine model of p210-BCR-ABL-induced MPD that gene targeting of Rac1 and Rac2 significantly delays or abrogates disease development. Attenuation of the disease phenotype is associated with severely diminished p210-BCR-ABL-induced downstream signaling in primary hematopoietic cells. We utilize NSC23766, a small molecule antagonist of Rac activation, to validate biochemically and functionally Rac as a molecular target in both a relevant animal model and in primary human CML cells in vitro and in a xenograft model in vivo, including in Imatinib-resistant p210-BCR-ABL disease. These data demonstrate that Rac is an additional therapeutic target in p210-BCR-ABL-mediated MPD.
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MESH Headings
- Aminoquinolines/pharmacology
- Animals
- Antigens, CD34/biosynthesis
- Cell Line, Tumor
- Dose-Response Relationship, Drug
- Fusion Proteins, bcr-abl/metabolism
- Gene Expression Regulation, Leukemic
- Hematopoietic Stem Cells/metabolism
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Mice
- Myeloproliferative Disorders/genetics
- Myeloproliferative Disorders/metabolism
- Myeloproliferative Disorders/therapy
- Neoplasm Transplantation
- Phenotype
- Pyrimidines/pharmacology
- rac GTP-Binding Proteins/metabolism
- rac GTP-Binding Proteins/physiology
- rac1 GTP-Binding Protein/metabolism
- RAC2 GTP-Binding Protein
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Affiliation(s)
- Emily K Thomas
- Division of Experimental Hematology, Cincinnati Children's Research Foundation, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
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Qin T, Youssef EM, Jelinek J, Chen R, Yang AS, Garcia-Manero G, Issa JPJ. Effect of cytarabine and decitabine in combination in human leukemic cell lines. Clin Cancer Res 2007; 13:4225-32. [PMID: 17634552 DOI: 10.1158/1078-0432.ccr-06-2762] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE 1-beta-D-Arabinofuranosylcytosine (cytarabine; ara-C) is the most active agent in myeloid leukemia. 5-Aza-2'-deoxycytidine (DAC) is a cytosine analogue that inhibits DNA methylation and also has activity in myeloid leukemia. Therefore, we investigated combining these two drugs in human leukemia cell lines in vitro. EXPERIMENTAL DESIGN We initially examined the effects of ara-C and DAC on human leukemia cell lines HL60, ML-1, RAji, and Jurkat. We measured IC(50) of DAC and ara-C in these cell lines and calculated a combination index of these two drugs given either simultaneously or sequentially. In searching for mechanisms relative to epigenetic regulation for this effect, we examined DNA methylation of LINE and Alu repetitive elements as a surrogate for global genomic DNA methylation. In addition, we sorted Annexin V positive and negative cells and measured differences in LINE methylation between them. RESULTS The combination of DAC and ara-C showed additive induction of cell death in ML-1 and synergistic induction in HL60, Raji, and Jurkat. Sequentially, DAC followed by ara-C was a synergistic combination in all cell lines. Low-dose DAC induced more hypomethylation than high doses of the drug, whereas ara-C had no effects on methylation. The combination of ara-C with DAC either together or DAC followed by ara-C resulted in inhibition of LINE demethylation in HL60. The RIL gene, which is silenced by DNA hypermethylation, was activated by DAC, but the addition of ara-C to DAC reduced RIL gene activation. DAC treatment increased H3 Lys(9) acetylation of Alu elements, whereas ara-C had no effect, and the addition of ara-C to DAC inhibited this effect. Finally, we showed that after DAC exposure, Annexin V positive cells were more hypomethylated than Annexin V negative cells. CONCLUSION The combination of DAC and ara-C showed additive or synergistic effects on cell death in four human leukemia cell lines in vitro, but antagonism in terms of epigenetic effects. One possible explanation for these paradoxical observations is that hypomethylated cells are sensitized to cell killing by ara-C. These data suggest that DAC used in combination with ara-C has clinical potential in the treatment of acute myeloid leukemia.
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Affiliation(s)
- Taichun Qin
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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31
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Abstract
Chronic myeloid leukaemia (CML) was the first neoplastic disease for which knowledge of the genotype led to a rationally designed therapy. As a result of its well known pathophysiology, straightforward diagnosis, well established prognostic factors, and treatment for the cause of disease, CML has been studied to an extent that far exceeds that expected from its frequency, and serves as a model disease for other cancers. Imatinib, an inhibitor of BCR-ABL tyrosine kinase, has revolutionised treatment of this disease, and is now recommended as standard treatment for chronic-phase CML. Interferon alfa is an acceptable alternative treatment in the early chronic phase for patients who do not tolerate imatinib. If imatinib treatment fails, allogeneic stem-cell transplantation, a dose increase of imatinib, or new drugs are recommended. Up to 87% of patients achieve complete cytogenetic remission, therefore we provide guidance for monitoring disease status. Many trials of new drugs and combination therapies that include imatinib are underway.
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Affiliation(s)
- Rüdiger Hehlmann
- III Medizinische Universitätsklinik, Medizinische Fakultät Mannheim der Universität Heidelberg, Mannheim, Germany.
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32
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Dilda PJ, Hogg PJ. Arsenical-based cancer drugs. Cancer Treat Rev 2007; 33:542-64. [PMID: 17624680 DOI: 10.1016/j.ctrv.2007.05.001] [Citation(s) in RCA: 276] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 05/21/2007] [Accepted: 05/23/2007] [Indexed: 01/04/2023]
Abstract
Arsenic is a semi-metal or metalloid with two biologically important oxidation states, As(III) and As(V). As(III), in particular, reacts with closely spaced protein thiols, forming stable cyclic dithioarsinite complexes in which both sulfur atoms are bound to arsenic. It is this reaction that is mostly responsible for arsenics cytotoxicity. Arsenic compounds have been used as medicinal agents for many centuries for the treatment of diseases such as psoriasis, syphilis, and rheumatosis. From the 1700's until the introduction of and use of modern chemotherapy and radiation therapy in the mid 1900's, arsenic was a mainstay in the treatment of leukemia. Concerns about the toxicity of arsenical compounds led eventually to their abandonment for the treatment of cancer. The discovery in the 1980's that arsenic trioxide induces complete remission in a high percentage of patients with acute promyelocytic leukemia has awakened interest in this metalloid for the treatment of human disease. In particular, a new class or organoarsenicals are being trialed for the treatment of hematological malignancies and solid tumors. In this review, we discuss the arsenical-based compounds used in the past and present for the treatment of various forms of cancer. Mechanisms of action and selectivity and acute and chronic toxicities are discussed along with the prospects of this class of molecule.
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Affiliation(s)
- Pierre J Dilda
- UNSW Cancer Research Centre, University of New South Wales and Department of Haematology, Prince of Wales Hospital, Sydney 2052, Australia
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Oki Y, Kantarjian HM, Gharibyan V, Jones D, O'brien S, Verstovsek S, Cortes J, Morris GM, Garcia-Manero G, Issa JPJ. Phase II study of low-dose decitabine in combination with imatinib mesylate in patients with accelerated or myeloid blastic phase of chronic myelogenous leukemia. Cancer 2007; 109:899-906. [PMID: 17236224 DOI: 10.1002/cncr.22470] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Resistance to imatinib is a frequent clinical problem in advanced phase chronic myelogenous leukemia (CML). A Phase II study was performed on low-dose decitabine, a DNA methyltransferase inhibitor, in combination with imatinib in patients with CML in accelerated phase (AP) and myeloid blastic phase (BP). METHODS Patients received decitabine 15 mg/m(2) intravenously daily, 5 days a week for 2 weeks, and imatinib 600 mg orally daily. Global DNA methylation was measured by long interspersed nucleotide element (LINE) bisulfite/pyrosequencing. RESULTS Twenty-eight patients were enrolled (25 with imatinib resistance; 18 in AP, 10 in BP). A total of 91 cycles (median, 2.5 cycles per patient) was administered. Complete hematologic responses, partial hematologic responses, and hematologic improvement were observed in 9 (32%), 1 (4%), and 2 (7%) patients. Major and minor cytogenetic responses were observed in 5 (18%) and 3 (11%) patients. The hematologic response rate was higher in patients without BCR-ABL kinase mutations (10 of 19, 53%) than in those with mutations (1 of 7, 14%). Median duration of hematologic response was 18 (range, 4 to 107+) weeks. Myelosuppression was the major adverse effect, with neutropenic fever in 9 patients (32%). LINE methylation decreased from 71.6% +/- 0.9% (mean +/- standard error of the mean) to 60.4% +/- 2.0% on Day 5, 60.5% +/- 1.8% on Day 12, and returned to 68.8% +/- 1.4% at peripheral blood recovery. A decrease in LINE methylation tended to be greater in nonresponders than in responders on Days 5 and 12. CONCLUSIONS Combination therapy with decitabine and imatinib is well tolerated and active in advanced phase CML without BCR-ABL kinase mutations.
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Affiliation(s)
- Yasuhiro Oki
- Department of Leukemia, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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34
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Yoon P, Giafis N, Smith J, Mears H, Katsoulidis E, Sassano A, Altman J, Redig AJ, Tallman MS, Platanias LC. Activation of mammalian target of rapamycin and the p70 S6 kinase by arsenic trioxide in BCR-ABL-expressing cells. Mol Cancer Ther 2007; 5:2815-23. [PMID: 17121928 DOI: 10.1158/1535-7163.mct-06-0263] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arsenic trioxide (As(2)O(3)) exhibits important antitumor activities in vitro and in vivo, but the precise mechanisms by which it induces its effects are not known. We provide evidence that during treatment of BCR-ABL-expressing cells with As(2)O(3), there is activation of a cellular pathway involving the p70 S6 kinase (p70S6K). Our data show that p70S6K is rapidly phosphorylated on Thr(421) and Ser(424) and is activated in an As(2)O(3)-inducible manner. The mammalian target of rapamycin (mTOR) is also phosphorylated/activated in an As(2)O(3)-inducible manner, and its activity is required for downstream engagement of p70S6K. p70S6K subsequently phosphorylates the S6 ribosomal protein on Ser(235)/Ser(236) and Ser(240)/Ser(244) to promote initiation of mRNA translation. Treatment of chronic myelogenous leukemia-derived cell lines with As(2)O(3) also results in phosphorylation of the 4E-BP1 repressor of mRNA translation on Thr(37)/Thr(46) and Thr(70), sites required for its deactivation and its dissociation from the eukaryotic initiation factor 4E complex to allow cap-dependent mRNA translation. In studies to determine the functional relevance of this pathway, we found that inhibition of mTOR and downstream cascades enhances induction of apoptosis by As(2)O(3). Consistent with this, the mTOR inhibitor rapamycin strongly potentiated As(2)O(3)-mediated suppression of primitive leukemic progenitors from the bone marrow of chronic myelogenous leukemia patients. Altogether, our data show that the mTOR/p70S6K pathway is activated in a negative feedback regulatory manner in response to As(2)O(3) in BCR-ABL-transformed cells and plays a key regulatory role in the induction of anti-leukemic responses.
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MESH Headings
- Antineoplastic Agents/pharmacology
- Arsenic Trioxide
- Arsenicals/pharmacology
- Dose-Response Relationship, Drug
- Fusion Proteins, bcr-abl
- Humans
- K562 Cells
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Oxides/pharmacology
- Phosphorylation/drug effects
- Protein Kinases/metabolism
- Protein-Tyrosine Kinases/metabolism
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Signal Transduction/drug effects
- TOR Serine-Threonine Kinases
- Tumor Cells, Cultured
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Affiliation(s)
- Patrick Yoon
- Robert H. Lurie Comprehensive Cancer Center, 303 East Superior Street, Lurie 3-107, Chicago, IL 60611, USA
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35
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La Rosée P, Jia T, Demehri S, Härtel N, de Vries P, Bonham L, Hollenback D, Singer JW, Melo JV, Druker BJ, Deininger MW. Antileukemic activity of lysophosphatidic acid acyltransferase-beta inhibitor CT32228 in chronic myelogenous leukemia sensitive and resistant to imatinib. Clin Cancer Res 2007; 12:6540-6. [PMID: 17085669 DOI: 10.1158/1078-0432.ccr-06-0140] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Lysophosphatidic acid acyltransferase (LPAAT)-beta catalyzes the conversion of lysophosphatidic acid to phosphatidic acid, an essential component of several signaling pathways, including the Ras/mitogen-activated protein kinase pathway. Inhibition of LPAAT-beta induces growth arrest and apoptosis in cancer cell lines, implicating LPAAT-beta as a potential drug target in neoplasia. EXPERIMENTAL DESIGN In this study, we investigated the effects of CT32228, a specific LPAAT-beta inhibitor, on BCR-ABL-transformed cell lines and primary cells from patients with chronic myelogenous leukemia. RESULTS CT32228 had antiproliferative activity against BCR-ABL-positive cell lines in the nanomolar dose range, evidenced by cell cycle arrest in G2-M and induction of apoptosis. Treatment of K562 cells with CT32228 led to inhibition of extracellular signal-regulated kinase 1/2 phosphorylation, consistent with inhibition of mitogen-activated protein kinase signaling. Importantly, CT32228 was highly active in cell lines resistant to the Bcr-Abl kinase inhibitor imatinib. Combination of CT32228 with imatinib produced additive inhibition of proliferation in cell lines with residual sensitivity toward imatinib. In short-term cultures in the absence of growth factors, CT32228 preferentially inhibited the growth of granulocyte-macrophage colony-forming units from chronic myelogenous leukemia patients compared with healthy controls. CONCLUSION These data establish LPAAT-beta as a potential drug target for the treatment of BCR-ABL-positive leukemias.
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Affiliation(s)
- Paul La Rosée
- Division of Hematology and Medical Oncology, Oregon Health and Sciences University, Portland, Oregon
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36
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Hu J, Zhou GB, Wang ZY, Chen SJ, Chen Z. Mutant Transcription Factors and Tyrosine Kinases as Therapeutic Targets for Leukemias: From Acute Promyelocytic Leukemia to Chronic Myeloid Leukemia and Beyond. Adv Cancer Res 2007; 98:191-220. [PMID: 17433911 DOI: 10.1016/s0065-230x(06)98006-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Mutations in transcription factors (TFs) and protein tyrosine kinases (PTKs), which result in inhibition of differentiation/apoptosis or enhanced proliferative/survival advantage of hematopoietic stem/progenitor cells, are two classes of the most frequently detected genetic abnormalities in leukemias. The critical roles for mutant TFs and/or PTKs to play in leukemogenesis, and the absence of mutant TFs/PTKs in normal hematopoietic cells, suggest that the two types of aberrant molecules may serve as ideal therapeutic targets. The great success of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) in treating acute promyelocytic leukemia through modulation of the causative PML-RARalpha oncoprotein represents the first two paradigms of mutant TFs-targeting therapeutic strategies for leukemia. More recently, tyrosine kinase inhibitor STI-571/Imatinib mesylate/Gleevec in the treatment of Breakpoint Cluster Region-Abelson (BCR-ABL) positive leukemia elicits paradigm of mutant PTKs as ideal antileukemia targets. Thus to further improve clinical outcome of leukemia patients, elucidation of pathogenesis of leukemia, screening for oncoprotein-targeting small molecules, as well as rationally designed combination of drugs with potential synergy are of importance.
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MESH Headings
- Antineoplastic Agents/therapeutic use
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Promyelocytic, Acute/drug therapy
- Leukemia, Promyelocytic, Acute/genetics
- Leukemia, Promyelocytic, Acute/metabolism
- Mutation/genetics
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/genetics
- Transcription Factors/antagonists & inhibitors
- Transcription Factors/genetics
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Affiliation(s)
- Jiong Hu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University (SJTU) and Shanghai Center for Systems Biomedicine, SJTU, Shanghai 200025, China
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37
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Potin S, Bertoglio J, Bréard J. Involvement of a Rho-ROCK-JNK pathway in arsenic trioxide-induced apoptosis in chronic myelogenous leukemia cells. FEBS Lett 2006; 581:118-24. [PMID: 17182041 DOI: 10.1016/j.febslet.2006.12.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Revised: 11/09/2006] [Accepted: 12/02/2006] [Indexed: 01/21/2023]
Abstract
The apoptotic signals activated by As(2)O(3) in the chronic myelogenous leukemia (CML) cell lines K562 and KCL22 were investigated. As(2)O(3) was found to induce apoptosis in these cells via the intrinsic pathway. As(2)O(3) also induced a sustained c-Jun NH2-terminal kinase (JNK) activation which preceded and was necessary for caspase-9 activation. We established that Rho and its effector, the kinase ROCK, are activated by As(2)O(3). Inhibition of either Rho or ROCK prevented JNK activation and protected against apoptosis. Thus, in CML cells, apoptosis induced by As(2)O(3) is mediated, at least in part, via a Rho-ROCK-JNK axis. These findings define a novel signaling pathway for As(2)O(3)-induced apoptosis.
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Affiliation(s)
- Sophie Potin
- Inserm U749, Faculté de Pharmacie, 5 rue JB Clément, 92290 Châtenay-Malabry, France
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Abstract
PURPOSE OF REVIEW Despite the excellent clinical results with imatinib in chronic myeloid leukemia, most patients have minimal residual disease and others will develop resistance and may eventually progress. Thus there is a need for developing approaches to overcome and prevent resistance to imatinib. RECENT FINDINGS Several new agents have been developed with significant activity in imatinib-resistant chronic myeloid leukemia. A second generation of more potent tyrosine kinase inhibitors, some with dual activity against Abl and Src, have shown very impressive results. Other agents, such as hypomethylating agents, farnesyl transferase inhibitors and homoharringtonine, have also shown preclinical and clinical promise. The use of vaccines as a way of providing an immunomodulatory approach to chronic myeloid leukemia is starting to develop as a major strategy to achieve eradication of the disease. SUMMARY Multiple effective agents are being developed to overcome resistance to imatinib. The challenge for the future is to incorporate them into effective strategies that can eliminate the disease and cure all patients with chronic myeloid leukemia.
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MESH Headings
- Animals
- Antineoplastic Agents/therapeutic use
- Benzamides
- Cancer Vaccines
- Clinical Trials, Phase II as Topic
- Drug Resistance, Neoplasm/drug effects
- Farnesyltranstransferase/antagonists & inhibitors
- Humans
- Imatinib Mesylate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/physiopathology
- Models, Animal
- Neoplasm, Residual
- Piperazines/therapeutic use
- Protein Kinase Inhibitors/therapeutic use
- Pyrimidines/therapeutic use
- src-Family Kinases/antagonists & inhibitors
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Affiliation(s)
- Jorge Cortes
- Department of Leukemia, University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
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39
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Hochhaus A. Chronic myelogenous leukemia (CML): resistance to tyrosine kinase inhibitors. Ann Oncol 2006; 17 Suppl 10:x274-9. [PMID: 17018738 DOI: 10.1093/annonc/mdl273] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- A Hochhaus
- III Medizinische Klinik, Medizinische Fakultät Mannheim der Universität Heidelberg, Mannheim, Germany
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40
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McCallum L, Price S, Planque N, Perbal B, Pierce A, Whetton AD, Irvine AE. A novel mechanism for BCR-ABL action: stimulated secretion of CCN3 is involved in growth and differentiation regulation. Blood 2006; 108:1716-23. [PMID: 16670264 DOI: 10.1182/blood-2006-04-016113] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Chronic myeloid leukemia (CML) is characterized by the presence of the constitutively active BCR-ABL protein tyrosine kinase. Using a multipotent hemopoietic cell line, FDCP-Mix, expressing BCR-ABL tyrosine kinase, we investigated the initial effects of this kinase in primitive hematopoietic stem cells. We identified down-regulation of a novel gene, CCN3, as a direct consequence of BCR-ABL kinase activity. CCN3 has been reported to function as a tumor suppressor gene in solid tumors. Northern and Western blotting plus immunocytochemical analysis confirmed CCN3 expression is decreased and is tyrosine-phosphorylated in BCR-ABL kinase active FDCP-Mix cells. Decreased cellular CCN3 correlated with increased CCN3 secretion in BCR-ABL kinase active cells. In vitro treatment of human CML cell lines with imatinib or siRNA directed against BCR-ABL significantly reduced BCR-ABL while increasing CCN3 expression. Cells from patients responding to imatinib showed a similar decrease in BCR-ABL and increase in CCN3. CML CD34+ cells treated with imatinib in vitro demonstrated increased CCN3 protein. Transfecting CCN3 into BCR-ABL+ cells inhibited proliferation and decreased clonogenic potential. CCN3 plays an important role in internal and external cell-signaling pathways. Thus, BCR-ABL can regulate protein levels by governing secretion, a novel mechanism for this tyrosine kinase.
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Affiliation(s)
- Lynn McCallum
- Department of Haematology, Centre for Cancer Research and Cell Biology, Queen's University Belfast, University Floor, Tower Block, Belfast City Hospital, Lisburn Road, Belfast BT9 7AB, United Kingdom
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41
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Aloisi A, Di Gregorio S, Stagno F, Guglielmo P, Mannino F, Sormani MP, Bruzzi P, Gambacorti-Passerini C, Saglio G, Venuta S, Giustolisi R, Messina A, Vigneri P. BCR-ABL nuclear entrapment kills human CML cells: ex vivo study on 35 patients with the combination of imatinib mesylate and leptomycin B. Blood 2006; 107:1591-8. [PMID: 16249386 DOI: 10.1182/blood-2005-05-2123] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The BCR-ABL oncoprotein of chronic myelogenous leukemia (CML) localizes to the cell cytoplasm, where it activates proliferative and antiapoptotic signaling pathways. We previously reported that the combination of the ABL kinase inhibitor imatinib mesylate (IM) and the nuclear export inhibitor leptomycin B (LMB) traps BCR-ABL inside the nucleus, triggering the death of the leukemic cells. To evaluate the efficacy of the combination of IM and LMB on human cells we collected CD34-positive cells from 6 healthy donors and myeloid progenitors from 35 patients with CML. The sequential addition of IM and LMB generated the strongest reduction in the proliferative potential of the leukemic cells, with limited toxicity to normal myeloid precursors. Furthermore, nested reverse transcriptase-polymerase chain reaction (RT-PCR) analysis on colonies representative of each experimental condition demonstrated that the combination of IM and LMB was the most effective regimen in reducing the number of BCR-ABL-positive colonies. The efficacy of the 2-drug association was independent of the clinical characteristics of the patients. Our results indicate that strategies aimed at the nuclear entrapment of BCR-ABL efficiently kill human leukemic cells, suggesting that the clinical development of this approach could be of significant therapeutic value for newly diagnosed and IM-resistant CML patients.
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Affiliation(s)
- Alessandra Aloisi
- Department of Biomedical Sciences, Section of General Pathology, University of Catania, Via Androne, 83-95124 Catania, Italy
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Walz C, Sattler M. Novel targeted therapies to overcome imatinib mesylate resistance in chronic myeloid leukemia (CML). Crit Rev Oncol Hematol 2006; 57:145-64. [PMID: 16213151 DOI: 10.1016/j.critrevonc.2005.06.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2005] [Revised: 06/28/2005] [Accepted: 06/28/2005] [Indexed: 02/06/2023] Open
Abstract
Imatinib mesylate (Gleevec) was developed as the first molecularly targeted therapy that specifically inhibits the BCR-ABL tyrosine kinase activity in patients with Philadelphia chromosome positive (Ph+) chronic myeloid leukemia (CML). Due to its excellent hematologic and cytogenetic responses, particularly in patients with chronic phase CML, imatinib has moved towards first-line treatment for newly diagnosed CML. Nevertheless, resistance to the drug has been frequently reported and is attributed to the fact that transformation of hematopoietic stem cells by BCR-ABL is associated with genomic instability. Point mutations within the ABL tyrosine kinase of the BCR-ABL oncoprotein are the major cause of resistance, though overexpression of the BCR-ABL protein and novel acquired cytogenetic aberrations have also been reported. A variety of strategies derived from structural studies of the ABL-imatinib complex have been developed, resulting in the design of novel ABL inhibitors, including AMN107, BMS-354825, ON012380 and others. The major goal of these efforts is to create new drugs that are more potent than imatinib and/or more effective against imatinib-resistant BCR-ABL clones. Some of these drugs have already been successfully tested in preclinical studies where they show promising results. Additional approaches are geared towards targeting the expression or stability of the BCR-ABL kinase itself or targeting signaling pathways that are chronically activated and required for transformation. In this review, we will discuss the underlying mechanisms of resistance to imatinib and novel targeted approaches to overcome imatinib resistance in CML.
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Affiliation(s)
- Christoph Walz
- Department of Medical Oncology, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA
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43
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Saulle E, Riccioni R, Pelosi E, Stafness M, Mariani G, De Tuglie G, Peschle C, Testa U. In vitro dual effect of arsenic trioxide on hemopoiesis: inhibition of erythropoiesis and stimulation of megakaryocytic maturation. Blood Cells Mol Dis 2005; 36:59-76. [PMID: 16360329 DOI: 10.1016/j.bcmd.2005.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 10/10/2005] [Indexed: 10/25/2022]
Abstract
Although the arsenic compounds are now widely utilized in clinics in the treatment of various tumors, their effects on normal hematopoiesis do not seem to have been explored. In the present study, we provide evidence that arsenic trioxide (As(2)O(3)) exerts in vitro a potent inhibitory effect on normal erythropoiesis and a stimulatory action on megakaryocytic differentiation. The effect of As(2)O(3) on erythroid and megakaryocytic differentiation was evaluated on both erythroleukemic cell lines K562 and HEL and on normal hemopoietic progenitor cells (HPCs) induced to selective erythroid or megakaryocytic differentiation. The inhibitory effect of As(2)O(3) on erythropoiesis is related to: (a) the inhibition of Stat5 activation with consequent reduced expression of the target genes Bcl-X(L) and glycophorin-A; (b) the activation of an apoptotic mechanism that leads to the cleavage of the erythroid transcription factors Tal-1 and GATA-1, whose integrity is required for erythroid cell survival and differentiation; (c) the reduced expression of heat shock protein 70, required for GATA-1 integrity. The stimulatory effect of As(2)O(3) on normal megakaryocytopoiesis is seemingly related to upmodulation of GATA-2 expression and to stimulation of MAPK activity. These observations may have implications for the patients undergoing anti-leukemic treatment with this compound.
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Affiliation(s)
- Ernestina Saulle
- Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
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44
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Chandra J, Tracy J, Loegering D, Flatten K, Verstovsek S, Beran M, Gorre M, Estrov Z, Donato N, Talpaz M, Sawyers C, Bhalla K, Karp J, Sausville E, Kaufmann SH. Adaphostin-induced oxidative stress overcomes BCR/ABL mutation-dependent and -independent imatinib resistance. Blood 2005; 107:2501-6. [PMID: 16291594 PMCID: PMC1895739 DOI: 10.1182/blood-2005-07-2966] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The BCR/ABL kinase has been targeted for the treatment of chronic myelogenous leukemia (CML) by imatinib mesylate. While imatinib has been extremely effective for chronic phase CML, blast crisis CML and Ph+ acute lymphoblastic leukemia (ALL) are often resistant. In particular, mutation of the T315 residue in the bcr/abl activation loop renders cells highly resistant to imatinib and to second-generation kinase inhibitors such as BMS-354825 or AMN107. Adaphostin is a tyrphostin that was originally intended to inhibit the BCR/ABL kinase by competing with its peptide substrates. Recent findings have in addition implicated reactive oxygen species (ROS) in the cytotoxic mechanism of adaphostin. In view of this unique mode of action, we examined the effects of adaphostin on numerous imatinib-resistant leukemia models, including imatinib-resistant CML and Ph+ ALL cell lines, cells harboring point mutations in BCR/ABL, and specimens from imatinib-resistant CML patients, using assays for intracellular ROS, apoptosis, and clonogenicity. Every model of imatinib resistance examined remained fully sensitive to adaphostin-induced cell death. Collectively, these data suggest that ROS generation by adaphostin overcomes even the most potent imatinib resistance in CML and Ph+ ALL.
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Affiliation(s)
- Joya Chandra
- Department of Pediatrics Research, University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
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45
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Abstract
This review highlights decitabine as a prototype epigenetic modifying drug to show how the clinical development of epigenetic agents differs from that of traditional cytotoxic chemotherapies. Decitabine, a cytosine analogue, is cytotoxic at high doses but has selective DNA demethylating activity at low doses. The focus of current decitabine investigations is twofold: to elucidate all of the mechanisms of action and to determine the optimal dose, schedule, and concomitant therapies. New phase I trials have identified a "biologically effective dose," which is 1 to 2 logs lower than the cytotoxic dose. A clinical development program with low-dose decitabine in malignant diseases is focused on myelodysplastic syndrome (MDS), acute myelogenous leukemia (AML), and chronic myelogenous leukemia (CML). A phase III trial in MDS showed objective responses (complete [CR] plus partial [PR] remission) and longer median time to progression to AML or death with decitabine than with supportive care alone. The optimal use of decitabine may be in combination with other agents that promote gene expression, namely, histone deacetylase (HDAC) inhibitors. Optimized decitabine doses and combinations with other epigenetic therapies that can be used at minimally toxic doses provide potentially safer therapeutic options and introduce novel combination therapies.
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46
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Swords R, Quinn J, Fay M, O'Donnell R, Goldman J, Murphy PT. CML clonal evolution with resistance to single agent imatinib therapy. ACTA ACUST UNITED AC 2005; 27:347-9. [PMID: 16178920 DOI: 10.1111/j.1365-2257.2005.00721.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe a 58-year-old male diagnosed with chronic myeloid leukaemia (CML) who failed to have a cytogenetic response to interferon-alpha and hydroxyurea. On subsequent therapy with imatinib mesylate he failed to have any cytogenetic response but also developed a complex clonal evolution with an additional Philadelphia (Ph) chromosome and trisomy 8 respectively in two Ph-positive subclones. The addition of cytosine arabinoside to imatinib resulted in reversion to single Ph-chromosome positivity with the disappearance of the previous additional clonal abnormalities. The case demonstrates the efficacy of combined treatment with imatinib and cytarabine in the management of CML resistant to single agent imatinib.
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MESH Headings
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Benzamides
- Cell Transformation, Neoplastic/chemically induced
- Cell Transformation, Neoplastic/genetics
- Clone Cells/pathology
- Cytarabine/therapeutic use
- Drug Resistance, Neoplasm
- Humans
- Hydroxyurea/therapeutic use
- Imatinib Mesylate
- Interferon-alpha/therapeutic use
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Male
- Middle Aged
- Philadelphia Chromosome
- Piperazines/adverse effects
- Piperazines/therapeutic use
- Pyrimidines/adverse effects
- Pyrimidines/therapeutic use
- Remission Induction/methods
- Treatment Failure
- Trisomy
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Affiliation(s)
- R Swords
- Department of Haematology, Beaumont Hospital, Dublin, Ireland.
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47
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Chuah C, Barnes DJ, Kwok M, Corbin A, Deininger MWN, Druker BJ, Melo JV. Zoledronate inhibits proliferation and induces apoptosis of imatinib-resistant chronic myeloid leukaemia cells. Leukemia 2005; 19:1896-904. [PMID: 16167056 DOI: 10.1038/sj.leu.2403949] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although imatinib mesylate has revolutionized the treatment of chronic myeloid leukaemia (CML), resistance to the drug, manifesting as relapse after an initial response or persistence of disease, remains a therapeutic challenge. In order to overcome this, alternative or additional targeting of signaling pathways downstream of Bcr-Abl may provide the best option for improving clinical response. Bisphosphonates, such as zoledronate, have been shown to inhibit the oncogenicity of Ras, an important downstream effector of Bcr-Abl. In this study, we show that zoledronate is equally effective in inhibiting the proliferation and clonogenicity of both imatinib-sensitive and -resistant CML cells, regardless of their mechanism of resistance. This is achieved by the induction of S-phase cell cycle arrest and apoptosis, through the inhibition of prenylation of Ras and Ras-related proteins by zoledronate. The combination of imatinib and zoledronate also augmented the activity of either drug alone and this occurred in imatinib-resistant CML cells as well. Since zoledronate is already available for clinical use, these results suggest that it may be an effective addition to the armamentarium of drugs for the treatment of CML.
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Affiliation(s)
- C Chuah
- Imperial College London, Hammersmith Hospital, London, UK
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48
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Abstract
The treatment of chronic myeloid leukemia has changed dramatically in the last few years. Stem-cell transplantation and the use of interferon alfa had already offered the possibility of complete and durable cytogenetic responses, improving the survival over that expected with conventional chemotherapy. The introduction of imatinib mesylate has started the era of molecular therapy with remarkable results including complete cytogenetic responses in up to 90% of patients and major molecular responses in most. However, some patients, particularly those treated in the advanced stages, may develop resistance to imatinib. Thus there has been interest in developing new agents that would not only help patients for whom imatinib is ineffective or intolerable, but that could also be combined with the intention of eliminating all evidence of disease. Several approaches are being pursued. These include new and more potent tyrosine kinase inhibitors that may not be affected by the most common mutations seen in the clinic. Some of these agents also inhibit Src-related kinases that may play a role in the development of resistance to imatinib. Other agents are directed at downstream or alternative pathways in leukemic cells, exploring potential synergy with imatinib. Another approach is to pursue an immune modulation that might eliminate small amounts of residual disease. Many of these agents are already showing promising results in the clinic. This manuscript reviews some of these agents, particularly those for which clinical data are already available.
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MESH Headings
- Benzamides
- Cancer Vaccines/administration & dosage
- Clinical Trials as Topic
- Combined Modality Therapy
- Dose-Response Relationship, Drug
- Drug Administration Schedule
- Drug Delivery Systems
- Drug Therapy, Combination
- Female
- Hematopoietic Stem Cell Transplantation/methods
- Humans
- Imatinib Mesylate
- Interferon-alpha/administration & dosage
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Male
- Piperazines/administration & dosage
- Prognosis
- Pyrimidines/administration & dosage
- Sensitivity and Specificity
- Severity of Illness Index
- Survival Analysis
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Affiliation(s)
- Jorge Cortes
- Department of Leukemia, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Unit 428, Houston, TX 77030, USA.
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49
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Abstract
Arsenic, a natural substance that has been used as a drug for over 2000 years, has been revived because of its remarkable therapeutic efficacy in patients with acute promyelocytic leukemia (APL). Arsenic exerts a dose-dependent dual effect: it causes differentiation at low concentrations and apoptosis at relatively high concentrations. Specific degradation of the leukemogenic PML-RARalpha fusion protein induced by arsenic leads to the differentiation of leukemia cells. The arsenic-induced apoptosis occurs through direct effects on mitochondria, causing the release of apoptotic proteins into the cytosol and the activation of caspases. Preliminary in vitro studies have also extended the potential anti-cancer effect of arsenic to non-APL leukemias, lymphoid malignancies and other cancers. In vitro and in vivo studies demonstrate that arsenic exerts a broad spectrum of anti-cancer effects by induction of apoptosis, inhibition of cell proliferation, anti-angiogenesis and possible immunomodulation. Phase I and II clinical trials are underway to evaluate the feasibility, safety and potential effect of arsenic in various cancer types.
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Affiliation(s)
- Jiong Hu
- Department of Hematology, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Second Medical University, Shanghai, China
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50
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Issa JPJ, Gharibyan V, Cortes J, Jelinek J, Morris G, Verstovsek S, Talpaz M, Garcia-Manero G, Kantarjian HM. Phase II study of low-dose decitabine in patients with chronic myelogenous leukemia resistant to imatinib mesylate. J Clin Oncol 2005; 23:3948-56. [PMID: 15883410 DOI: 10.1200/jco.2005.11.981] [Citation(s) in RCA: 246] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
PURPOSE To determine the activity of decitabine, a DNA methylation inhibitor, in imatinib-refractory or intolerant chronic myelogenous leukemia. MATERIALS AND METHODS Thirty-five patients were enrolled in this phase II study (12 in chronic phase, 17 in accelerated phase, and six in blastic phase). Decitabine was administered at 15 mg/m2 intravenously over 1 hour daily, 5 days a week for 2 weeks. DNA methylation was measured using a LINE1 bisulfite/pyrosequencing assay. RESULTS Complete hematologic responses were seen in 12 patients (34%) and partial hematologic responses in seven patients (20%), for an overall hematologic response rate of 54% (83% in chronic phase, 41% in accelerated phase, and 34% in blastic phase). Major cytogenetic responses were observed in six patients (17%), and minor cytogenetic responses were seen in 10 patients (29%) for an overall cytogenetic response rate of 46%. Median response duration was 3.5 months (range, 2 to 13+ months). Myelosuppression was the major adverse effect, with neutropenic fever in 28 (23%) of 124 courses of therapy. LINE1 methylation decreased from 71.3% +/- 1.4% (mean +/- standard error of the mean) to 60.7% +/- 1.4% after 1 week, 50.9% +/- 2.4% after 2 weeks, and returned to 66.5% +/- 2.7% at recovery of counts (median, 46 days). LINE1 methylation at the end of week 1 did not correlate with subsequent responses. However, at day 12, the absolute decrease in methylation was 14.5% +/- 3.0% versus 26.8% +/- 2.7% in responders versus nonresponders (P = .007). CONCLUSION Decitabine induces hypomethylation and has clinical activity in imatinib refractory chronic myelogenous leukemia. We hypothesize that the inverse correlation between hypomethylation 2 weeks after therapy and response is due to a cell death mechanism of response, whereby resistant cells can withstand more hypomethylation.
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Affiliation(s)
- Jean-Pierre J Issa
- Department of Leukemia and Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
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