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He C, Peng Z, Zhang D, Guo Y, Liang T, Zhao Y, Yu L, Zhang Q, Chang Z, Xiao Y, Li N, Xue H, Wu S, Zhao ZJ, Zhang C, Chen Y. Sunitinib selectively targets leukemogenic signaling of mutant SHP2 in juvenile myelomonocytic leukemia. Biochem Pharmacol 2023; 213:115588. [PMID: 37187274 DOI: 10.1016/j.bcp.2023.115588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/08/2023] [Accepted: 05/08/2023] [Indexed: 05/17/2023]
Abstract
Leukemogenic SHP2 mutations occur in 35% of patients with juvenile myelomonocytic leukemia (JMML), a hematopoietic malignancy with poor response to cytotoxic chemotherapy. Novel therapeutic strategies are urgently needed for patients with JMML. Previously, we established a novel cell model of JMML with HCD-57, a murine erythroleukemia cell line that depends on EPO for survival. SHP2-D61Y or -E76K drove the survival and proliferation of HCD-57 in absence of EPO. In this study, we identified sunitinib as a potent compound to inhibit SHP2-mutant cells by screening a kinase inhibitor library with our model. We used cell viability assay, colony formation assay, flow cytometry, immunoblotting, and a xenograft model to evaluate the effect of sunitinib against SHP2-mutant leukemia cells in vitro and in vivo. The treatment of sunitinib selectively induced apoptosis and cell cycle arrest in mutant SHP2-transformed HCD-57, but not parental cells. It also inhibited cell viability and colony formation of primary JMML cells with mutant SHP2, but not bone marrow mononuclear cells from healthy donors. Immunoblotting showed that the treatment of sunitinib blocked the aberrantly activated signals of mutant SHP2 with deceased phosphorylation levels of SHP2, ERK, and AKT. Furthermore, sunitinib effectively reduced tumor burdens of immune-deficient mice engrafted with mutant-SHP2 transformed HCD-57. Our data demonstrated that sunitinib selectively inhibited SHP2-mutant leukemia cells, which could serve as an effective therapeutic strategy for SHP2-mutant JMML in the future.
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Affiliation(s)
- Chunxiao He
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Zhiyong Peng
- Nanfang-Chunfu Children's Institute of Hematology, Taixin Hospital, Dongguan, Guangdong, China
| | - Dengyang Zhang
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Yao Guo
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Tianqi Liang
- Department of Pediatrics, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Yuming Zhao
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Liuting Yu
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Qi Zhang
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Zhiguang Chang
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Yan Xiao
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Na Li
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Hongman Xue
- Department of Pediatrics, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Shunjie Wu
- Department of Hematology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Zhizhuang Joe Zhao
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Changhua Zhang
- Digestive Diseases Center, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen, Guangdong, China.
| | - Yun Chen
- Edmond H. Fischer Translational Medical Research Laboratory, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China.
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De Vos N, Hofmans M, Lammens T, De Wilde B, Van Roy N, De Moerloose B. Targeted therapy in juvenile myelomonocytic leukemia: Where are we now? Pediatr Blood Cancer 2022; 69:e29930. [PMID: 36094370 DOI: 10.1002/pbc.29930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 11/07/2022]
Abstract
Juvenile myelomonocytic leukemia (JMML) is a rare and aggressive clonal neoplasm of early childhood, classified as an overlap myeloproliferative/myelodysplastic neoplasm by the World Health Organization. In 90% of the patients with JMML, typical initiating mutations in the canonical Ras pathway genes NF1, PTPN11, NRAS, KRAS, and CBL can be identified. Hematopoietic stem cell transplantation (HSCT) currently is the established standard of care in most patients, although long-term survival is still only 50-60%. Given the limited therapeutic options and the important morbidity and mortality associated with HSCT, new therapeutic approaches are urgently needed. Hyperactivation of the Ras pathway as disease mechanism in JMML lends itself to the use of targeted therapy. Targeted therapy could play an important role in the future treatment of patients with JMML. This review presents a comprehensive overview of targeted therapies already developed and evaluated in vitro and in vivo in patients with JMML.
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Affiliation(s)
- Nele De Vos
- Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University, Ghent, Belgium
| | - Mattias Hofmans
- Department of Laboratory Medicine, Ghent University Hospital, Ghent, Belgium.,Cancer Research Institute Ghent, Ghent, Belgium
| | - Tim Lammens
- Cancer Research Institute Ghent, Ghent, Belgium.,Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Bram De Wilde
- Cancer Research Institute Ghent, Ghent, Belgium.,Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Nadine Van Roy
- Cancer Research Institute Ghent, Ghent, Belgium.,Center for Medical Genetics Ghent, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Barbara De Moerloose
- Cancer Research Institute Ghent, Ghent, Belgium.,Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium.,Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
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Induced Pluripotent Stem Cells to Model Juvenile Myelomonocytic Leukemia: New Perspectives for Preclinical Research. Cells 2021; 10:cells10092335. [PMID: 34571984 PMCID: PMC8465353 DOI: 10.3390/cells10092335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/24/2021] [Accepted: 08/31/2021] [Indexed: 11/16/2022] Open
Abstract
Juvenile myelomonocytic leukemia (JMML) is a malignant myeloproliferative disorder arising in infants and young children. The origin of this neoplasm is attributed to an early deregulation of the Ras signaling pathway in multipotent hematopoietic stem/progenitor cells. Since JMML is notoriously refractory to conventional cytostatic therapy, allogeneic hematopoietic stem cell transplantation remains the mainstay of curative therapy for most cases. However, alternative therapeutic approaches with small epigenetic molecules have recently entered the stage and show surprising efficacy at least in specific subsets of patients. Hence, the establishment of preclinical models to test novel agents is a priority. Induced pluripotent stem cells (IPSCs) offer an opportunity to imitate JMML ex vivo, after attempts to generate immortalized cell lines from primary JMML material have largely failed in the past. Several research groups have previously generated patient-derived JMML IPSCs and successfully differentiated these into myeloid cells with extensive phenotypic similarities to primary JMML cells. With infinite self-renewal and the capability to differentiate into multiple cell types, JMML IPSCs are a promising resource to advance the development of treatment modalities targeting specific vulnerabilities. This review discusses current reprogramming techniques for JMML stem/progenitor cells, related clinical applications, and the challenges involved.
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Smith FO, Dvorak CC, Braun BS. Myelodysplastic Syndromes and Myeloproliferative Neoplasms in Children. Hematology 2018. [DOI: 10.1016/b978-0-323-35762-3.00063-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Sakashita K, Matsuda K, Koike K. Diagnosis and treatment of juvenile myelomonocytic leukemia. Pediatr Int 2016; 58:681-90. [PMID: 27322988 DOI: 10.1111/ped.13068] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 04/25/2016] [Accepted: 05/24/2016] [Indexed: 12/13/2022]
Abstract
Juvenile myelomonocytic leukemia (JMML) is a rare myelodysplastic/myeloproliferative disorder that occurs during infancy and early childhood; this disorder is characterized by hypersensitivity of the myeloid progenitor cells to granulocyte-macrophage colony-stimulating factor in vitro. JMML usually involves somatic and/or germline mutations in the genes of the RAS pathway, including PTPN11, NRAS, KRAS, NF1, and CBL, in the leukemic cells. Almost all patients with JMML experience an aggressive clinical course, and hematopoietic stem cell transplantation (HSCT) is the only curative treatment. A certain proportion of patients with somatic NRAS and germline mutations in CBL, however, have spontaneous resolution. A suitable treatment after diagnosis and conditioning regimen prior to HSCT are yet to be determined, but several clinical trials have been initiated throughout the world to develop suitable pre- or post-allogeneic HSCT treatments and new targeted therapies that are less toxic, to improve patient outcome.
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Affiliation(s)
- Kazuo Sakashita
- Department of Pediatric Hematology and Oncology, Nagano Children's Hospital, Azumono, Japan
| | - Kazuyuki Matsuda
- Department of Laboratory Medicine, Shinshu University Hospital, Matsumoto, Japan
| | - Kenichi Koike
- Department of Pediatrics, Shinshu University School of Medicine, Matsumoto, Japan
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Choi J, Polcher A, Joas A. Systematic literature review on Parkinson's disease and Childhood Leukaemia and mode of actions for pesticides. ACTA ACUST UNITED AC 2016. [DOI: 10.2903/sp.efsa.2016.en-955] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Stieglitz E, Ward AF, Gerbing RB, Alonzo TA, Arceci RJ, Liu YL, Emanuel PD, Widemann BC, Cheng JW, Jayaprakash N, Balis FM, Castleberry RP, Bunin NJ, Loh ML, Cooper TM. Phase II/III trial of a pre-transplant farnesyl transferase inhibitor in juvenile myelomonocytic leukemia: a report from the Children's Oncology Group. Pediatr Blood Cancer 2015; 62:629-36. [PMID: 25704135 PMCID: PMC4339233 DOI: 10.1002/pbc.25342] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 10/01/2014] [Indexed: 02/04/2023]
Abstract
BACKGROUND Juvenile myelomonocytic leukemia (JMML) is not durably responsive to chemotherapy, and approximately 50% of patients relapse after hematopoietic stem cell transplant (HSCT). Here we report the activity and acute toxicity of the farnesyl transferase inhibitor tipifarnib, the response rate to 13-cis retinoic acid (CRA) in combination with cytoreductive chemotherapy, and survival following HSCT in children with JMML. PROCEDURE Eighty-five patients with newly diagnosed JMML were enrolled on AAML0122 between 2001 and 2006. Forty-seven consented to receive tipifarnib in a phase II window before proceeding to a phase III trial of CRA in combination with fludarabine and cytarabine followed by HSCT and maintenance CRA. Thirty-eight patients enrolled only in the phase III trial. RESULTS Overall response rate was 51% after tipifarnib and 68% after fludarabine/cytarabine/CRA. Tipifarnib did not increase pre-transplant toxicities. Forty-six percent of the 44 patients who received protocol compliant HSCT relapsed. Five-year overall survival was 55 ± 11% and event-free survival was 41 ± 11%, with no significant difference between patients who did or did not receive tipifarnib. CONCLUSIONS Administration of tipifarnib in the window setting followed by HSCT in patients with newly diagnosed JMML was safe and yielded a 51% initial response rate as a single agent, but failed to reduce relapse rates or improve long-term overall survival.
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Affiliation(s)
- Elliot Stieglitz
- Department of Pediatrics, University of California San Francisco School of Medicine and Benioff Children’s Hospital, Helen Diller Comprehensive Cancer Center, San Francisco, CA, USA
| | - Ashley F. Ward
- Department of Pediatrics, University of California San Francisco School of Medicine and Benioff Children’s Hospital, Helen Diller Comprehensive Cancer Center, San Francisco, CA, USA
| | | | | | - Robert J. Arceci
- Ronald A. Matricaria Institute of Molecular Medicine, Phoenix Children’s Hospital, University of Arizona, Phoenix, AZ, USA
| | - Y. Lucy Liu
- University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Peter D. Emanuel
- University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | | | | | | | - Frank M. Balis
- The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Nancy J. Bunin
- The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Mignon L. Loh
- Department of Pediatrics, University of California San Francisco School of Medicine and Benioff Children’s Hospital, Helen Diller Comprehensive Cancer Center, San Francisco, CA, USA
| | - Todd M. Cooper
- Aflac Cancer and Blood Disorders Center, Emory University School of Medicine/Children’s Healthcare of Atlanta, Atlanta, GA, USA
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9
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Brown P, Hunger SP, Smith FO, Carroll WL, Reaman GH. Novel targeted drug therapies for the treatment of childhood acute leukemia. Expert Rev Hematol 2014; 2:145. [PMID: 20126514 DOI: 10.1586/ehm.09.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The cure rates for childhood acute leukemia have dramatically improved to approximately 70% overal, with treatments that include intensive cytotoxic chemotherapy and, in some cases, hematopoietic stem cell transplantation. However, many children still die of their disease or of treatment-related toxicities. Even in patients that are cured, there can be significant and, not uncommonly debilitating, acute and late complications of treatment. Improved understanding of the molecular and cellular biology of leukemia and the increasing availability of high-throughput genomic techniques have facilitated the development of molecularly targeted therapies that have the potential to be more effective and less toxic than the standard approaches. In this article, we review the progress to date with agents that are showing promise in the treatment of childhood acute leukemia, including monoclonal antibodies, inhibitors of kinases and other signaling molecules (e.g., BCR-ABL, FLT3, farnesyltransferase, mTOR and γ-secretase), agents that target epigenetic regulation of gene expression (DNA methyltransferase inhibitors and histone deacetylase inhibitors) and proteasome inhibitors. For the specific agents in each of these classes, we summarize the published preclinical data and the clinical trials that have been completed, are in progress or are being planned for children with acute leukemia. Finally, we discuss potential challenges to the success of molecularly targeted therapy, including proper target identification, adequate targeting of leukemia stem cells, developing synergistic and tolerable combinations of agents and designing adequately powered clinical trials to test efficacy in molecularly defined subsets of patients.
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Affiliation(s)
- Patrick Brown
- Departments of Oncology and Pediatrics, Sidney Kimmel Comprehensive Cancer, Center and Johns Hopkins University, School of Medicine, 1650 Orleans Street, CRB1 Room 2M49, Baltimore, MD 21231, USA, Tel.: +1 410 955 8817, ,
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10
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Molecular targets for the treatment of juvenile myelomonocytic leukemia. Adv Hematol 2011; 2012:308252. [PMID: 22162691 PMCID: PMC3226315 DOI: 10.1155/2012/308252] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 07/13/2011] [Accepted: 08/11/2011] [Indexed: 01/23/2023] Open
Abstract
Significant advances in our understanding of the genetic defects and the pathogenesis of juvenile myelomonocytic leukemia (JMML) have been achieved in the last several years. The information gathered tremendously helps us in designing molecular targeted therapies for this otherwise fatal disease. Various approaches are being investigated to target defective pathways/molecules in this disease. However, effective therapy is still lacking. Development of specific target-based drugs for JMML remains a big challenge and represents a promising direction in this field.
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Yoshimi A, Kojima S, Hirano N. Juvenile myelomonocytic leukemia: epidemiology, etiopathogenesis, diagnosis, and management considerations. Paediatr Drugs 2010; 12:11-21. [PMID: 20034338 DOI: 10.2165/11316200-000000000-00000] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Juvenile myelomonocytic leukemia (JMML) is a rare hematopoietic malignancy of early childhood with features characteristic of both myelodysplastic and myeloproliferative disorders. Recent studies clearly show that the deregulated activation of the RAS signaling pathway plays a central role in the pathogenesis of JMML. Somatic defects in either RAS, PTPN11 or NF1 genes involved in this pathway are detected in 70-80% of JMML patients, allowing a molecular diagnosis to be made in the majority of cases. Patients with JMML respond poorly to chemotherapy, and the probability of survival without allogeneic hematopoietic stem cell transplantation (HSCT) is less than 10%. Recent studies show that the event-free survival after HSCT is between 24 and 54%, with no difference between transplants using matched family donors and those using unrelated donors. The use of therapies such as intensive chemotherapy and splenectomy prior to HSCT does not improve the outcome. The relapse rate following HSCT is over 30%, which is unacceptably high. Cumulative evidence suggests that a graft-versus-leukemia effect occurs in JMML. Donor leukocyte infusion is not usually successful in JMML, but the outcome of second HSCT is generally favorable. Based on recent advances in the understanding of the pathogenesis of JMML, the development of novel targeted therapies, which might improve the outcome of patients, is keenly awaited.
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Affiliation(s)
- Ayami Yoshimi
- Department of HSCT Data Management, Nagoya University, Japan.
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The granulocyte-macrophage colony-stimulating factor receptor: linking its structure to cell signaling and its role in disease. Blood 2009; 114:1289-98. [PMID: 19436055 DOI: 10.1182/blood-2008-12-164004] [Citation(s) in RCA: 227] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Already 20 years have passed since the cloning of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha-chain, the first member of the GM-CSF/interleukin (IL)-3/IL-5 family of hemopoietic cytokine receptors to be molecularly characterized. The intervening 2 decades have uncovered a plethora of biologic functions transduced by the GM-CSF receptor (pleiotropy) and revealed distinct signaling networks that couple the receptor to biologic outcomes. Unlike other hemopoietin receptors, the GM-CSF receptor has a significant nonredundant role in myeloid hematologic malignancies, macrophage-mediated acute and chronic inflammation, pulmonary homeostasis, and allergic disease. The molecular mechanisms underlying GM-CSF receptor activation have recently been revealed by the crystal structure of the GM-CSF receptor complexed to GM-CSF, which shows an unexpected higher order assembly. Emerging evidence also suggests the existence of intracellular signosomes that are recruited in a concentration-dependent fashion to selectively control cell survival, proliferation, and differentiation by GM-CSF. These findings begin to unravel the mystery of cytokine receptor pleiotropy and are likely to also apply to the related IL-3 and IL-5 receptors as well as other heterodimeric cytokine receptors. The new insights in GM-CSF receptor activation have clinical significance as the structural and signaling nuances can be harnessed for the development of new treatments for malignant and inflammatory diseases.
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Chan RJ, Cooper T, Kratz CP, Weiss B, Loh ML. Juvenile myelomonocytic leukemia: a report from the 2nd International JMML Symposium. Leuk Res 2009; 33:355-62. [PMID: 18954903 PMCID: PMC2692866 DOI: 10.1016/j.leukres.2008.08.022] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 08/15/2008] [Accepted: 08/19/2008] [Indexed: 02/02/2023]
Abstract
Juvenile myelomonocytic leukemia (JMML) is an aggressive childhood myeloproliferative disorder characterized by the overproduction of myelomonocytic cells. JMML incidence approaches 1.2/million persons in the United States (Cancer Incidence and Survival Among Children and Adolescents: United States SEER Program 1975-1995). Although rare, JMML is innately informative as the molecular genetics of this disease implicates hyperactive Ras as an essential initiating event. Given that Ras is one of the most frequently mutated oncogenes in human cancer, findings from this disease are applicable to more genetically diverse and complex adult leukemias. The JMML Foundation (www.jmmlfoundation.org) was founded by parent advocates dedicated to finding a cure for this disease. They work to bring investigators together in a collaborative manner. This article summarizes key presentations from The Second International JMML Symposium, on 7-8 December 2007 in Atlanta, GA. A list of all participants is in Supplementary Table.
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Affiliation(s)
- Rebecca J. Chan
- Departments of Pediatrics, the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Todd Cooper
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Christian P. Kratz
- Department of Pediatrics and Adolescent Medicine, University of Freiburg, Freiburg, Germany
| | - Brian Weiss
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Mignon L. Loh
- Department of Pediatrics, University of California, San Francisco, CA, USA
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Macy ME, Sawczyn KK, Garrington TP, Graham DK, Gore L. Pediatric developmental therapies: interesting new drugs now in early-stage clinical trials. Curr Oncol Rep 2009; 10:477-90. [PMID: 18928662 DOI: 10.1007/s11912-008-0073-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The current high cure rates for children diagnosed with cancer can be attributed in part to emphasis on large cooperative group clinical trials. The significant improvement in pediatric cancer survival over the past few decades is the result of optimized chemotherapy drug dosing, timing, and intensity; however, further alterations in traditional chemotherapy agents are unlikely to produce substantially better outcomes. Furthermore, there remains a subset of patients who have a very poor prognosis due to tumor type or stage at presentation, or who have a dismal prognosis with relapse or recurrence. As such, innovative approaches to therapy and new drugs are clearly needed for introduction into the current pediatric oncology arsenal. A variety of biologically targeted therapies that have shown promise in preclinical studies and early-phase adult clinical trials are now being explored in pediatric clinical trials. These novel agents hold the promise for continuing to drive forward improvements in patient survival, with potentially less toxicity than exists with traditional chemotherapy drugs.
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Abstract
While acute myeloid leukemia (AML) is significantly less common than acute lymphoblastic leukemia (ALL) in childhood, it is significantly more deadly with only half as many children likely to be cured with standard therapy. In addition, the typical treatment for AML is among the most toxic of treatments for pediatric cancer; it includes intensive multiagent chemotherapy and, often, hematopoietic stem cell transplantation. Given the poor prognosis of pediatric AML and the significant toxicity of standard AML therapy, novel therapies are needed. Improved understanding of the molecular and cellular biology of leukemia has facilitated the development of molecularly targeted therapies. In this article, we review progress to date with agents that are showing promise in the treatment of pediatric AML including targeted immunoconjugates, inhibitors of signaling molecules (e.g. FMS-like tyrosine kinase 3 [FLT3], farnesyltransferase, and mammalian target of rapamycin [mTOR]), agents that target epigenetic regulation of gene expression (DNA methyltransferase inhibitors and histone deacetylase inhibitors), and proteasome inhibitors. For the specific agents in each of these classes, we summarize the published preclinical data and the clinical trials that have been completed, are in progress, or are being planned for children with AML. Finally, we discuss potential challenges to the success of molecularly targeted therapy including demonstrating adequate targeting of leukemia stem cells, developing synergistic and tolerable combinations of agents, and designing adequately powered clinical trials to test efficacy in molecularly defined subsets of patients.
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Affiliation(s)
- Patrick Brown
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland, USA.
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Koike K, Matsuda K. Recent advances in the pathogenesis and management of juvenile myelomonocytic leukaemia. Br J Haematol 2008; 141:567-75. [PMID: 18422786 DOI: 10.1111/j.1365-2141.2008.07104.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kenichi Koike
- Department of Paediatrics, Shinshu University School of Medicine, Matsumoto, Japan.
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Handgretinger R, Kurtzberg J, Egeler RM. Indications and donor selections for allogeneic stem cell transplantation in children with hematologic malignancies. Pediatr Clin North Am 2008; 55:71-96, x. [PMID: 18242316 DOI: 10.1016/j.pcl.2007.10.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Allogeneic stem cell transplantation (SCT) is the only curative approach for many patients with advanced or high-risk leukemia. Advances in supportive care and management of graft-versus-host disease have resulted in improvements in outcomes of related and unrelated donor SCT, creating controversies as to which strategy might be the optimal therapy for individual patients. This article discusses the indications and donor selection strategies for SCT in patients with malignant hematologic disease.
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Affiliation(s)
- Rupert Handgretinger
- Department of Hematology/Oncology and General Pediatrics, Children's University Hospital, Hoppe-Seyler-Strasse 1, Tuebingen, Germany.
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Abstract
Abnormalities of cytokine and growth factor signaling pathways are characteristic of all forms of leukemia: lymphoid and myeloid, acute and chronic. In normal hematopoietic cells, cytokines provide the stimulus for proliferation, survival, self-renewal, differentiation and functional activation. In leukemic cells, these pathways are usurped to subserve critical parts of the malignant program. In this review, our current knowledge of leukemic cell cytokine signaling will be summarized, and some speculations on the significance and implications of these insights will be advanced. A better understanding of aberrant cytokine signaling in leukemia should provide additional targets for the rational therapy of these diseases.
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Affiliation(s)
- R A Van Etten
- Molecular Oncology Research Institute and Division of Hematology/Oncology, Tufts-New England Medical Center, Boston, MA 02111, USA.
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Tefferi A, Gilliland G. Classification of chronic myeloid disorders: From Dameshek towards a semi-molecular system. Best Pract Res Clin Haematol 2006; 19:365-85. [PMID: 16781478 DOI: 10.1016/j.beha.2005.07.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hematological malignancies are phenotypically organized into lymphoid and myeloid disorders, although such a distinction might not be precise from the standpoint of lineage clonality. In turn, myeloid malignancies are broadly categorized into either acute myeloid leukemia (AML) or chronic myeloid disorder (CMD), depending on the presence or absence, respectively, of AML-defining cytomorphologic and cytogenetic features. The CMD are traditionally classified by their morphologic appearances into discrete clinicopathologic entities based primarily on subjective technologies. It has now become evident that most CMD represent clonal stem cell processes where the primary oncogenic event has been characterized in certain instances; Bcr/Abl in chronic myeloid leukemia, FIP1L1-PDGFRA or c-kit(D816V) in systemic mastocytosis, rearrangements of PDGFRB in chronic eosinophilic leukemia, and rearrangements of FGFR1 in stem cell leukemia/lymphoma syndrome. In addition, Bcr/Abl-negative classic myeloproliferative disorders are characterized by recurrent JAK2(V617F) mutations, whereas other mutations affecting the RAS signaling pathway molecules have been associated with juvenile myelomonocytic leukemia. Such progress is paving the way for a transition from a histologic to a semi-molecular classification system that preserves conventional terminology, while incorporating new information on molecular pathogenesis.
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Affiliation(s)
- Ayalew Tefferi
- Division of Hematology, Mayo Clinic College of Medicine, Rochester 55905, USA.
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20
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Abstract
Myeloid disorders constitute a subgroup of hematological malignancies that is separate from lymphoid disorders. The World Health Organization system for classification of tumors of the hematopoietic system divides myeloid disorders into acute myeloid leukemia and chronic myeloid disorders based on the presence or absence, respectively, of acute myeloid leukemia--defining morphological and cytogenetic features including the presence of 20% or more myeloblasts in either the bone marrow or the peripheral blood. A recently proposed semimolecular classification system for chronic myeloid disorders recognizes 3 broad categories: the myelodysplastic syndrome, classic myeloproliferative disorders (MPD), and atypical MPD. Classic MPD includes polycythemia vera, essential thrombocythemia, myelofibrosis with myeloid metaplasia, and chronic myeloid leukemia. Both myelodysplastic syndrome and BCR/ABL-negative classic MPD were previously discussed as part of the current ongoing symposium on hematological malignancies. The current review focuses on the diagnosis and treatment of both molecularly defined and clinicopathologically assigned categories of atypical MPD: chronic myelomonocytic leukemia, juvenile myelomonocytic leukemia, chronic neutrophilic leukemia, chronic basophilic leukemia, chronic eosinophilic leukemia, idiopathic eosinophilia including hypereosinophilic syndrome, systemic mastocytosis, unclassified MPD, and eosinophilic/mast cell disorders associated with mutations of platelet-derived growth factor receptors alpha (PDGFRA) and beta (PDGFRB), FGFR1, and KIT.
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Affiliation(s)
- Ayalew Tefferi
- Division of Hematology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
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21
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Hasegawa D, Manabe A, Kubota T, Kawasaki H, Hirose I, Ohtsuka Y, Tsuruta T, Ebihara Y, Goto YI, Zhao XY, Sakashita K, Koike K, Isomura M, Kojima S, Hoshika A, Tsuji K, Nakahata T. Methylation status of the p15 and p16 genes in paediatric myelodysplastic syndrome and juvenile myelomonocytic leukaemia. Br J Haematol 2005; 128:805-12. [PMID: 15755284 DOI: 10.1111/j.1365-2141.2005.05392.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Aberrant DNA methylation is frequently observed in adults with myelodysplastic syndrome (MDS), and is recognized as a critical event in the disease's pathogenesis and progression. This is the first report to investigate the methylation status of p15 and p16, cell cycle regulatory genes, in children with MDS (n = 9) and juvenile myelomonocytic leukaemia (JMML; n = 18) by using a methylation-specific polymerase chain reaction. The frequency of p15 hypermethylation in paediatric MDS was 78% (7/9), which was comparable to that in adult MDS. In contrast, p15 hypermethylation in JMML was a rare event (17%; 3/18). In JMML, clinical and laboratory characteristics including PTPN11 mutations and aberrant colony formation were not different between the three patients with hypermethylated p15 and the others. Aberrant methylation of p16 was not detected in children with either MDS or JMML. Since p15 and p16 genes were unmethylated in two children with JMML, in whom the disease had progressed with an increased number of blasts, a condition referred to as blastic crisis, we infer that the aberrant methylation of these genes is not responsible for the progression of JMML. The results suggest that demethylating agents may be effective in most children with MDS and a few patients with JMML.
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Affiliation(s)
- Daisuke Hasegawa
- Department of Paediatric Haematology-Oncology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
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22
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Abstract
Juvenile myelomonocytic leukemia is an aggressive neoplasia of early childhood. Only allogeneic stem cell transplantation (SCT) offers long-term cure. In the absence of an HLA-matched family donor, early SCT from an unrelated donor is the treatment of choice for most children. With clear evidence of a graft-versus-leukemia effect and a high post-transplant relapse rate, the outcome of SCT depends, in part, on the management of immunosuppression during the procedure. The impact of pretransplant cytoreductive treatment, such as intensive chemotherapy, splenectomy, or 13-cis retinoic acid, is unclear. Hypersensitivity for granulocyte-macrophage colony-stimulating factor and pathologic activation of the Ras/MAPK pathway play an important role in the pathophysiology of juvenile myelomonocytic leukemia and provide the opportunity for several novel therapeutic approaches.
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Affiliation(s)
- Charlotte Marie Niemeyer
- Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, University of Freiburg, Mathildenstrasse 1, 79106 Freiburg, Germany.
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23
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Abstract
The classification of myeloid neoplasms now includes CMPD, mixed CMPD/ MDS, MDS, and acute myeloid leukemias. CMPD and CMPD/MDS, both clonal stem cell diseases, share myeloproliferative features, including typical hypercellular marrows, organomegaly, and cell lineage maturation. The CMPD generally differ by which myeloid cell lineage dominates hematopoiesis, and the main diseases include CML, PV, ET, and CIM. The mixed CMPD/MDS disorders also show dysplastic features and variable amounts of effective hematopoiesis; these disorders include CMML, JMML, and atypical CML. Given the overlap in morphology among these diseases, correlation with clinical, hematologic, and cytogenetic/molecular genetic findings is imperative for precise classification.
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Affiliation(s)
- Tracy I George
- Department of Pathology, Stanford University Medical Center, 300 Pasteur Drive, Room H1501B, Stanford, CA 94305-5627, USA.
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24
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Selleri C, Maciejewski JP, Montuori N, Ricci P, Visconte V, Serio B, Luciano L, Rotoli B. Involvement of nitric oxide in farnesyltransferase inhibitor-mediated apoptosis in chronic myeloid leukemia cells. Blood 2003; 102:1490-8. [PMID: 12714496 DOI: 10.1182/blood-2003-01-0178] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mechanism of action of farnesyltransferase inhibitors (FTIs) has not been fully clarified. We investigated the cytotoxic effects of various FTIs in chronic myeloid leukemia (CML), using LAMA cells and marrow cells from 40 CML patients in chronic phase. FTI-mediated cytotoxic effect was observed in LAMA cells and in 65% of primary CML cells, whereas marrow cells from controls were only weakly affected. Cytotoxic effects were partially related to enhanced apoptosis; however, Fas-receptor (FasR) and Fas-ligand (FasL) expression were not modified by FTIs. Susceptibility to FTI-mediated inhibition did not correlate with FasR/FasL expression in CD34+ CML cells. Moreover, intra-cellular activation of caspase-1 and -8 were not altered by FTIs, and their blockade did not reverse FTI toxicity. However, we observed FTI-induced activation of caspase-3, and its inhibition partially reverted FTI-induced apoptosis. FTIs did not modulate bcl2, bclxL, and bclxS expression, whereas they increased inducible nitric oxide (iNOS) mRNA and protein levels, resulting in higher NO production. Furthermore, C3 exoenzyme, a Rho inhibitor, significantly increased iNOS expression in CML cells, suggesting that FTIs may up-regulate NO formation at least partially through FTI-mediated inhibition of Rho. We conclude that FTIs induce selective apoptosis in CML cells via activation of iNOS and caspase-3.
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MESH Headings
- Alkyl and Aryl Transferases/antagonists & inhibitors
- Antigens, CD34/immunology
- Apoptosis/drug effects
- Bone Marrow Cells/metabolism
- Caspase 3
- Caspase Inhibitors
- Caspases/metabolism
- Enzyme Activation/drug effects
- Enzyme Inhibitors/pharmacology
- Farnesyltranstransferase
- Humans
- K562 Cells
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Neoplastic Stem Cells/metabolism
- Nitric Oxide/biosynthesis
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/biosynthesis
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type II
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Proto-Oncogene Proteins c-bcl-2/metabolism
- RNA, Messenger/biosynthesis
- fas Receptor/metabolism
- rhoA GTP-Binding Protein/antagonists & inhibitors
- rhoB GTP-Binding Protein/antagonists & inhibitors
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Affiliation(s)
- Carmine Selleri
- Division of Hematology, Federico II University, Naples, Italy.
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25
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Abstract
Juvenile myelomonocytic leukemia is an aggressive neoplasia of early childhood. Only allogeneic stem cell transplantation (SCT) offers a long-term cure. In the absence of an HLA-matched family donor, early SCT from an unrelated donor will be the treatment of choice for most children. With clear evidence of a graft-versus-leukemia effect and a high post-transplant relapse rate, outcome of SCT will depend, in part, on the management of immunosuppression during the procedure. The impact of pretransplant cytoreductive treatment, such as intensive chemotherapy, splenectomy, or 13-cis retinoic acid, is unclear. Hypersensitivity for granulocyte-macrophage colony-stimulating factor and pathologic activation of the Ras/MAPK pathway play an important role in the pathophysiology of juvenile myelomonocytic leukemia and will provide the opportunity for several novel therapy approaches.
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Affiliation(s)
- Charlotte Marie Niemeyer
- Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, University of Freiburg, Mathildenstrasse 1, 79106 Freiburg, Germany.
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26
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Mesa RA, Tefferi A, Gray LA, Reeder T, Schroeder G, Kaufmann SH. In vitro antiproliferative activity of the farnesyltransferase inhibitor R115777 in hematopoietic progenitors from patients with myelofibrosis with myeloid metaplasia. Leukemia 2003; 17:849-55. [PMID: 12750696 DOI: 10.1038/sj.leu.2402901] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
R115777 is an orally bioavailable farnesyltransferase inhibitor (FTI) that has displayed encouraging activity in patients with acute myeloid leukemia. To determine whether R115777 might exert similar activity in myelofibrosis with myeloid metaplasia (MMM), we evaluated its effects on circulating myeloid progenitor cells from patients with MMM (n=25) using in vitro colony-forming assays. The median R115777 concentrations that inhibited colony formation by 50% were 34 and 2.7 nM for myeloid and megakaryocytic colonies from MMM patients, respectively. Progenitors from normal controls and patients with other myeloproliferative disorders demonstrated similar sensitivity. Since the ras polypeptides are one putative target of FTIs, the potential role of ras effectors was examined by incubating parallel progenitor assays with the phosphatidyl-inositol-3 (PI-3) kinase inhibitor LY294002 and the mitogen-activated protein kinase 1 inhibitor PD98059. MMM progenitor colonies (n=7) were highly sensitive to LY294002 but not to PD98059, implying that the PI-3 kinase pathway may be critical for survival and proliferation of these cells. In addition to indicating that MMM progenitors are sensitive to clinically achievable R115777 concentrations in vitro, these results provide a potential explanation for the thrombocytopenia observed with R115777 during the treatment of other hematologic malignancies.
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Affiliation(s)
- R A Mesa
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
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27
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Salesse S, Verfaillie CM. BCR/ABL: from molecular mechanisms of leukemia induction to treatment of chronic myelogenous leukemia. Oncogene 2002; 21:8547-59. [PMID: 12476301 DOI: 10.1038/sj.onc.1206082] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
MESH Headings
- Antineoplastic Agents/therapeutic use
- Fusion Proteins, bcr-abl
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/physiopathology
- Protein-Tyrosine Kinases/genetics
- Protein-Tyrosine Kinases/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Stephanie Salesse
- Stem Cell Institute, Cancer Center and Department of Medicine, University of Minnesota Cancer Center, Minneapolis, Minnesota, MN 55455, USA
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28
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Keating A. Chronic myeloid leukemia: current therapies and the potential role of farnesyltransferase inhibitors. Semin Hematol 2002; 39:11-7. [PMID: 12214288 DOI: 10.1053/shem.2002.35979] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The treatment of patients with chronic myeloid leukemia (CML) is evolving rapidly. With conventional chemotherapy the clinical course is characterized by a chronic phase (median duration, 4 to 5 years), followed by an accelerated phase with transition to a terminal blast crisis. Treatment with busulfan or hydroxyurea does not alter the natural history. Interferon alfa (IFN-alpha) prolongs life expectancy by approximately 20 months but is associated with significant toxicity. Evidence indicates that bone marrow transplantation from a related human leukocyte antigen (HLA)-identical donor can be curative in younger patients. However, transplantation is available to only a minority of patients and entails severe toxicity and transplant-related mortality. Dramatic advances in the understanding of the molecular pathophysiology of CML have led to a new era of targeted therapy. The specific tyrosine kinase inhibitor imatinib mesylate demonstrates a high level of efficacy in CML with acceptable toxicity. Farnesyltransferase inhibitors (FTIs) are another important class of targeted agents with the potential to act at multiple sites within dysregulated signal transduction networks. ZARNESTRA (formerly R115777, Ortho Biotech Oncology, Raritan, NJ), an oral FTI, has shown activity and is well tolerated in both chronic- and accelerated-phase patients. With their mechanistic specificity, the new modalities offer the promise of increased antileukemic activity and an improved therapeutic index.
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29
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Iversen PO, Emanuel PD, Sioud M. Targeting Raf-1 gene expression by a DNA enzyme inhibits juvenile myelomonocytic leukemia cell growth. Blood 2002; 99:4147-53. [PMID: 12010819 DOI: 10.1182/blood.v99.11.4147] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Juvenile myelomonocytic leukemia (JMML) is an aggressive childhood disorder with few therapeutic options. Granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor-alpha (TNF-alpha) promote JMML cell growth. A hyperactive function of the ras oncogene is a hallmark of JMML. We therefore targeted the protein kinase Raf-1 downstream of Ras using a DNA enzyme that degrades mRNA-Raf-1. Western blots of JMML cell lysates revealed phosphorylated Raf-1 protein, indicating constitutive activation. Addition of GM-CSF, but not TNF-alpha, increased phosphorylation of both Raf-1 and the mitogen-activated protein kinases (MAPKs) JNK-1 and ERK-1. Depletion of Raf-1 protein markedly impaired activation of MAPKs, induced substantial inhibition of JMML cell colony formation, and virtually abolished GM-CSF hypersensitivity in JMML cells. Exogenous TNF-alpha, but not GM-CSF, restored colony formation of JMML cells pretreated with the enzyme. We could not detect any effect of the enzyme on the proliferation of normal bone marrow cells, indicating its specificity and potential safety. When immunodeficient mice engrafted with JMML cells were treated continuously with the enzyme via a peritoneal osmotic mini-pump for 4 weeks, a profound reduction in the JMML cell numbers in the recipient murine bone marrows was found. We conclude that GM-CSF is a chief regulator of JMML growth and exerts its proleukemic effects primarily via the Ras/Raf-1 signaling cascade. TNF-alpha plays a permissive role, being dependent upon GM-CSF to induce JMML cell proliferation. The DNA enzyme efficiently catabolized mRNA-Raf-1 with subsequent inhibition of JMML cell growth, suggesting its potential as a mechanism-based therapy in this fatal leukemia.
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Affiliation(s)
- Per Ole Iversen
- Institute for Nutrition Research, University of Oslo, and Department of Immunology, Molecular Medicine Group, the Norwegian Radium Hospital, Oslo, Norway.
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30
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Smith FO, King R, Nelson G, Wagner JE, Robertson KA, Sanders JE, Bunin N, Emaunel PD, Davies SM. Unrelated donor bone marrow transplantation for children with juvenile myelomonocytic leukaemia. Br J Haematol 2002; 116:716-24. [PMID: 11849238 DOI: 10.1046/j.0007-1048.2001.03333.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Children with juvenile myelomonocytic leukaemia (JMML) have a poor outcome, with survival in a minority of patients. The major limitation on success of sibling donor bone marrow transplantation for JMML has been reported to be relapse. A total of 46 children with a diagnosis of JMML underwent unrelated donor marrow (URD) transplantation facilitated by the National Marrow Donor Program. Forty-three of 46 patients had neutrophil engraftment at a median of 20 d post transplant, with platelet recovery in 28 of 40 evaluable patients at a median of 34.5 d. Thirty-two of 44 evaluable patients developed acute graft-versus-host-disease (GVHD) (Grades 2-4) and chronic GVHD developed in 14 of 35 evaluable patients. At a median follow-up of 2.0 years, probabilities of survival and disease-free survival were 42% and 24% respectively. The probability of relapse was 58% at 2 years and represents the major cause of treatment failure. Multivariate analysis revealed that chronic GVHD was associated with reduced relapse [risk ratio 0.20 (95% CI 0.04-1.02, P=0.05)] improved survival [risk ratio 0.13 (95% CI 0.03-0.68, P=0.02)] and event-free survival [risk ratio 0.23 (95% CI 0.06-0.94, P=0.04)]. This study demonstrates that relapse is the major cause of treatment failure in patients with JMML undergoing URD transplantation. With lower relapse observed in patients with chronic GVHD, new treatment strategies that focus on enhancing the graft-versus-leukaemia effect may improve survival.
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Affiliation(s)
- Franklin O Smith
- Division of Hematology/Oncology, Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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31
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Marson CM, Rioja AS, Brooke G, Coombes RC, Vigushin DM. Cyclic acid anhydrides as a new class of potent, selective and non-peptidic inhibitors of geranylgeranyl transferase. Bioorg Med Chem Lett 2002; 12:255-9. [PMID: 11755366 DOI: 10.1016/s0960-894x(01)00718-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Cyclic acid anhydrides possessing a lipid chain have been shown to be a new class of non-peptidic inhibitors of geranylgeranyl protein-transferase type I (GGPTase-I).
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Affiliation(s)
- Charles M Marson
- Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H OAJ, UK.
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32
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Morgan MA, Dolp O, Reuter CW. Cell-cycle-dependent activation of mitogen-activated protein kinase kinase (MEK-1/2) in myeloid leukemia cell lines and induction of growth inhibition and apoptosis by inhibitors of RAS signaling. Blood 2001; 97:1823-34. [PMID: 11238126 DOI: 10.1182/blood.v97.6.1823] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Disruption of the RAS-to-mitogen-activated protein kinase (MAPK/ERK) signaling pathway, either directly through activating RAS gene mutations or indirectly through other genetic aberrations, plays an important role in the molecular pathogenesis of myeloid leukemias. Constitutive activation of ERK-1/2 and MEK-1/2, which elicit oncogenic transformation in fibroblasts, has recently been observed in acute myeloid leukemias (AML). In this study, the activation of the RAS-to-MAPK cascade in 14 AML and 5 chronic myeloid leukemia (CML) cell lines is examined and correlated with the effects of a panel of 9 RAS signaling inhibitors on cell viability, colony formation, cell-cycle progression, and induction of apoptosis. Activation of MEK, ERK, and the transcription factors CREB-1, ATF-1, and c-Myc is demonstrated in the majority of the cell lines (9 of 14 AML and 2 of 5 CML cell lines). Although activation of the ERK cascade did not always correlate with the presence of activating RAS mutations or BCR-Abl, it is linked to the G0/G1 and the G2/M phase of the cell cycle. In contrast to most inhibitors (eg, B581, Cys-4-Abs-Met, FPT-2, FTI-276, and FTS), a significant growth inhibition was only observed for FTI-277 (19 of 19), FPT-3 (10 of 19), and the MEK inhibitors U0126 (19 of 19) and PD098059 (8 of 19). Treatment of NB-4 cells with FTI-277 primarily resulted in a G2/M block, whereas treatment with FPT-3 and U0126 led to induction of apoptosis. FTI-277 revealed strong toxicity toward normal purified CD34+ cells. The results suggest differences in the mechanisms of action and support a potential therapeutic usefulness of these inhibitors in the treatment of myeloid leukemias.
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Affiliation(s)
- M A Morgan
- Department of Hematology and Oncology, Section Molecular Biology, University of Ulm, Germany
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35
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Abstract
A series of alterations in the cellular genome affecting the expression or function of genes controlling cell growth and differentiation is considered to be the main cause of cancer. These mutational events include activation of oncogenes and inactivation of tumor suppressor genes. The elucidation of human cancer at the molecular level allows the design of rational, mechanism-based therapeutic agents that antagonize the specific activity of biochemical processes that are essential to the malignant phenotype of cancer cells. Because the frequency of RAS mutations is among the highest for any gene in human cancers, development of inhibitors of the Ras–mitogen-activated protein kinase pathway as potential anticancer agents is a very promising pharmacologic strategy. Inhibitors of Ras signaling have been shown to revert Ras-dependent transformation and cause regression of Ras-dependent tumors in animal models. The most promising new class of these potential cancer therapeutics are the farnesyltransferase inhibitors. The development of these compounds has been driven by the observation that oncogenic Ras function is dependent upon posttranslational modification, which enables membrane binding. In contrast to many conventional chemotherapeutics, farnesyltransferase inhibitors are remarkably specific and have been demonstrated to cause no gross systemic toxicity in animals. Some orally bioavailable inhibitors are presently being evaluated in phase II clinical trials. This review presents an overview on some inhibitors of the Ras signaling pathway, including their specificity and effectiveness in vivo. Because Ras signaling plays a crucial role in the pathogenesis of some hematologic malignancies, the potential therapeutic usefulness of these inhibitors is discussed.
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36
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Targeting the Ras signaling pathway: a rational, mechanism-based treatment for hematologic malignancies? Blood 2000. [DOI: 10.1182/blood.v96.5.1655] [Citation(s) in RCA: 201] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractA series of alterations in the cellular genome affecting the expression or function of genes controlling cell growth and differentiation is considered to be the main cause of cancer. These mutational events include activation of oncogenes and inactivation of tumor suppressor genes. The elucidation of human cancer at the molecular level allows the design of rational, mechanism-based therapeutic agents that antagonize the specific activity of biochemical processes that are essential to the malignant phenotype of cancer cells. Because the frequency of RAS mutations is among the highest for any gene in human cancers, development of inhibitors of the Ras–mitogen-activated protein kinase pathway as potential anticancer agents is a very promising pharmacologic strategy. Inhibitors of Ras signaling have been shown to revert Ras-dependent transformation and cause regression of Ras-dependent tumors in animal models. The most promising new class of these potential cancer therapeutics are the farnesyltransferase inhibitors. The development of these compounds has been driven by the observation that oncogenic Ras function is dependent upon posttranslational modification, which enables membrane binding. In contrast to many conventional chemotherapeutics, farnesyltransferase inhibitors are remarkably specific and have been demonstrated to cause no gross systemic toxicity in animals. Some orally bioavailable inhibitors are presently being evaluated in phase II clinical trials. This review presents an overview on some inhibitors of the Ras signaling pathway, including their specificity and effectiveness in vivo. Because Ras signaling plays a crucial role in the pathogenesis of some hematologic malignancies, the potential therapeutic usefulness of these inhibitors is discussed.
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37
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Abstract
Abstract
Over the last 2 decades, four major therapeutic approaches have drastically changed the prognosis in chronic myelogenous leukemia (CML): 1) allogeneic stem cell transplant (SCT); 2) interferon alpha (IFN-α) based regimens; 3) donor lymphocyte infusions (DLI); and 4) and the revolutionary BCR-ABL tyrosine kinase inhibitors such as STI571 (signal transduction inhibitor 571). Each modality has exploited and targeted different aspects of CML biology, and is associated with different risk-benefit ratios.
In Section I of this review, Dr. Melo reviews the molecular pathophysiology of CML and potential new targets for therapy including anti-sense strategies to disrupt the BCR-ABL gene and inhibition of the BCR-ABL tyrosine kinase activity.
In Section II, Dr. Tura, addresses important questions in the use of IFN-α for the treatment of CML, including the mechanism of action and the development of resistance, the optimal dose and duration of therapy and the prediction of response based on clinical features. An approach to the choice of therapy based on the predicted mortality is presented.
In Section III Dr. Giralt presents an update on the results of unrelated donor transplantion, donor lymphocyte infusions (DLI) and non-ablative stem cell transplantation (NST) in CML. The roles of CD8-depletion, dose escalation and the transduction of suicide genes in treatment with DLI are addressed. Early results of NST in CML show that it is feasible and can result in long-term disease control.
In Section IV Drs. Kantarjian and Talpaz review the results of IFN-α plus low-dose cytosine arabinoside and other promising modalities for CML including homoharringtonine, decitabine, and polyethylene glycol-interferon. In Section V they present an update on the recent experience with STI571. Objective but transient responses have been seen in 40% to 50% of patients in CML blastic phase. In accelerated phase, the response rate with STI571 exceeds 70%, and these responses are durable. In chronic phase CML, STI571 at 300 mg daily in patients who failed IFN-α produces a complete hematologic response (CHR) in over 90% of patients. Early results suggest cytogenetic response rates of approximately 50%, which may be major in approximately 30%. The maturing results with STI571 may soon change current recommendations regarding the relative roles of established modalities such as allogeneic SCT and IFN-α. Important questions include 1) whether STI571 therapy alone may be sufficient to induce long-term survival and event-free survival in CML, or whether it needs to be combined simultaneously or sequentially with IFN-α and cytosine arabinoside; and 2) what should the indications for frontline allogeneic SCT be in relation to STI571 therapy.
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38
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Abstract
Over the last 2 decades, four major therapeutic approaches have drastically changed the prognosis in chronic myelogenous leukemia (CML): 1) allogeneic stem cell transplant (SCT); 2) interferon alpha (IFN-α) based regimens; 3) donor lymphocyte infusions (DLI); and 4) and the revolutionary BCR-ABL tyrosine kinase inhibitors such as STI571 (signal transduction inhibitor 571). Each modality has exploited and targeted different aspects of CML biology, and is associated with different risk-benefit ratios.
In Section I of this review, Dr. Melo reviews the molecular pathophysiology of CML and potential new targets for therapy including anti-sense strategies to disrupt the BCR-ABL gene and inhibition of the BCR-ABL tyrosine kinase activity.
In Section II, Dr. Tura, addresses important questions in the use of IFN-α for the treatment of CML, including the mechanism of action and the development of resistance, the optimal dose and duration of therapy and the prediction of response based on clinical features. An approach to the choice of therapy based on the predicted mortality is presented.
In Section III Dr. Giralt presents an update on the results of unrelated donor transplantion, donor lymphocyte infusions (DLI) and non-ablative stem cell transplantation (NST) in CML. The roles of CD8-depletion, dose escalation and the transduction of suicide genes in treatment with DLI are addressed. Early results of NST in CML show that it is feasible and can result in long-term disease control.
In Section IV Drs. Kantarjian and Talpaz review the results of IFN-α plus low-dose cytosine arabinoside and other promising modalities for CML including homoharringtonine, decitabine, and polyethylene glycol-interferon. In Section V they present an update on the recent experience with STI571. Objective but transient responses have been seen in 40% to 50% of patients in CML blastic phase. In accelerated phase, the response rate with STI571 exceeds 70%, and these responses are durable. In chronic phase CML, STI571 at 300 mg daily in patients who failed IFN-α produces a complete hematologic response (CHR) in over 90% of patients. Early results suggest cytogenetic response rates of approximately 50%, which may be major in approximately 30%. The maturing results with STI571 may soon change current recommendations regarding the relative roles of established modalities such as allogeneic SCT and IFN-α. Important questions include 1) whether STI571 therapy alone may be sufficient to induce long-term survival and event-free survival in CML, or whether it needs to be combined simultaneously or sequentially with IFN-α and cytosine arabinoside; and 2) what should the indications for frontline allogeneic SCT be in relation to STI571 therapy.
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